JPH01190491A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To provide excellent releasability to an ink layer and to obtain a good printing image while generating no release noise, by providing an anchor layer containing a silicone resin between a support and a heat-meltable colorant layer. CONSTITUTION:A support to be used has not only good heat-resistant strength but also high dimensional stability and an anchor layer 2 containing a silicone resin is provided between said support and at least one heat-meltable colorant layer 3. This anchor layer promotes the interfacial release between the anchor layer and the heat-meltable colorant layer on the support and has action or function for improving the releasability of the heat-meltable colorant layer to enhance the quality of a printing image and suppresses the generation of release noise. This action or function is based on the silicone resin contained in the anchor layer and the silicone resin has a siloxane bond and, for example, is composed of organopolysiloxane represented by formula (1) (wherein R is an org. group and k is an integer of 1 or more) and the content of the silicone part of a silicone modified resin is within a range of 1-90wt.%.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a thermal transfer recording medium, and more specifically, the present invention relates to a thermal transfer recording medium that has an ink layer that has good releasability, realizes excellent print quality, and has low peeling sound. The present invention relates to a thermal transfer recording medium.

[Prior Art and Problems Therewith] In order to obtain a good printed image using a thermal transfer recording medium, it is necessary that the ink layer is accurately peeled off from the support depending on the heated portion of the ink layer.

In order to meet this requirement, a technique has long been known in which a layer called a release layer is interposed between the support and the ink layer for the purpose of improving the releasability of the support.

Generally, the release layer is a heat-melting material such as wax.
It is a layer that mainly contains a thermoplastic resin and a thermoplastic resin.1 Usually, each component is heated until it melts and then applied, or a coating solution that is dissolved or dispersed in an organic solvent is applied. formed on the support by.

In order to obtain a printed image with good quality,
It is desirable that the ink layer is transferred from the support side to the transfer medium by interfacial peeling between the release layer and the adjacent ink layer.

However, in conventional thermal transfer recording media, in addition to the above-mentioned interfacial peeling, interfacial peeling occurs at the interface between the support and the release layer adjacent to the support.

Cohesive failure peeling, etc., in which peeling occurs within the release layer, is likely to occur, and when such peeling occurs, there is a problem in that the print quality obtained deteriorates.

In addition, in conventional thermal transfer recording media having a peeling layer, a peeling sound is produced when the ink layer is peeled off from the support side, so if many thermal transfer recording media are used at the same time,
Another problem is that it can be quite noisy.

This invention has been made based on the above circumstances.

That is, an object of the present invention is to provide a thermal transfer recording medium that has an excellent releasability of an ink layer, can obtain a good printed image, and does not generate peeling sound.

[Means for solving the above-mentioned problems] In order to solve the above-mentioned problems, as a result of extensive studies, the inventors found that silicone resin is contained between the support and the heat-melting coloring material layer. This invention was achieved by discovering that a heat-sensitive transfer recording medium provided with an anchor layer has excellent peelability of the heat-fusible coloring material layer, can achieve good print quality, and generates almost no peeling sound. did.

That is, the structure of the present invention is a heat-sensitive transfer recording medium characterized by having an anchor layer containing a silicone resin between the support and the heat-melting coloring material layer.

The thermal transfer recording medium of the present invention, for example, as shown in FIG. 1, is formed by laminating at least an anchor layer 2 and a heat-melting coloring material layer 3 in this order on a support 1.

Single-support support The support in the thermal transfer recording medium of the present invention desirably has good heat-resistant strength and high dimensional stability.

The materials include, for example, papers such as plain paper, condenser paper, laminated paper, and coated paper; resin films such as polyethylene, polyethylene terephthalate, polystyrene, polypropylene, and polyimide; composites of paper and resin films; and aluminum. Any metal sheet such as foil is preferably used.

The thickness of the support is usually 3Q#Lm or less, preferably 2
~6Bm. If the thickness of the support exceeds 301 Lm, thermal conductivity may deteriorate, leading to deterioration in printing quality.

In addition, in the thermal transfer recording medium of this invention.

The structure on the back side of the support is arbitrary, and for example, a backing layer such as an anti-sticking layer may be provided.

-Anchor layer- One of the important points in this invention is to provide an anchor layer containing a silicone resin between the support and at least one heat-melting coloring material layer described in detail next. .

In this invention, the anchor layer remains on the support when the heat-melting coloring material layer is peeled off from the support, and promotes interfacial peeling between the anchor layer and the heat-melting coloring material layer. It has an action or function of improving the quality of a printed image by improving the releasability of the coloring material layer, and also has an action or function of suppressing the generation of peeling sound.

Such action or function of the anchor layer is brought about by the silicone resin contained in the anchor layer.

The silicone resin is a resin having a siloxane bond.

Specifically, for example, an organopolysiloxane represented by the following formula (1): [wherein R represents an organic group and k represents an integer of 1 or more]; ~(
8): % formula %) Me:+S! O-[SiO]r, -SiMe3 [However, in formulas (2) to (8), m, n, a, b and C are integers greater than or equal to 0, and m and n are 0 at the same time.
R1 is an alkyl group, and Ha is an alkyl group having 1 to 40 carbon atoms or other organic group. Further, Me is a methyl group. ] Examples include modified polysiloxane resins represented by the following.

Furthermore, in this invention, in addition to the organopolysiloxane and modified polysiloxane resin, silicone modified resins such as silicone modified acrylic resin, silicone modified urethane resin, silicone modified urea resin, and silicone modified epoxy resin may be used. can.

These silicone-modified resins are, for example, acrylic resins, urethane resins, urea resins, epoxy resins, etc. modified with polysiloxane.

The silicone-modified acrylic resin is, for example, the following formula (9): [In formula (9), R''' and R4 have carbon atoms of l
It is any one of a monovalent aliphatic hydrocarbon group, a phenyl group, and a monovalent halogenated hydrocarbon group within the range of ~lO, and is an integer of 1 or more.

Furthermore, R'l and R4 may be the same or different from each other.] An organopolysiloxane represented by the following formula (1); or a methyl group, R6 is any one of a methyl group, an ethyl group, and a phenyl group, and X is any one of a chlorine atom, a methoxy group, and an ethoxy group. ] or an organopolysiloxane represented by the above formula (9) and the following formula (■); [However, in formula (II), R5, R6 and X are as defined above. They have the same meaning. ] Acrylic compound represented by and/or the following formula (■); C11g = C-C-C-0-(Cl1 z-3i-
X3(m) [However, in formula (m), X has the same meaning as above. ] Examples include condensation reaction products with acrylic compounds represented by:

As the silicone-modified urethane resin, for example, 1
The following formula (10).

%formula%) Or the following formula (11).

(However, in Equation (10) and Equation (11), m,
n, n, and R2 are integers greater than or equal to 0, and m and n
Or m, n, and R2 cannot be ○ at the same time, and R7 is.

and , where the symbol represents an integer of 1 or more. )
and the following formula (12): [However, in the formula (12), Re is an aliphatic, aromatic, or aliphatic divalent group, preferably a carbon filtrate.
is an alkyl group having 6 to 10 carbon atoms or an aromatic group having 6 to 10 carbon atoms. Moreover, R9 is an alkyl group having 1 to 6 carbon atoms, preferably a methyl group. Further, R3 is a value such that the average molecular weight is approximately 500 to 5000, preferably a value such that the average molecular weight is approximately 1.000 to 50000.

Examples include resins obtained by addition polymerizing a polyurethane polyol represented by the following formula and an organic polyisocyanate.

Examples of the silicone-modified urea resin include resins obtained by addition polymerizing a polysiloxane polyamine represented by the following formula (13) and an organic polyisocyanate.

[However, in formula (13), Rδ R9 and R3 are.

They have the same meanings as those in formula (12) above. ] As the silicone-modified epoxy resin, for example, an epoxy resin represented by the following formula (A): [In formula (A), R'' is an aliphatic group] is modified with a methoxylated silicone intermediate. Examples include resins obtained by

In the various silicone-modified resins, the content of the silicone portion is usually within the range of 1 to 90% by weight,
Preferably it is within the range of 5 to 50% by weight.

These silicone resins may be used alone or
The two inserts 1 may be used in combination.

Among these, those with a softening point of 100°C or higher are preferred, and those with a softening point of 150°C or higher are particularly preferred. When using a material with a softening point of less than 100°C, it is preferable to harden the anchor layer using a crosslinking agent. By hardening the anchor layer, the heat-melting coloring material layer formed on the anchor layer can be Stable coating can be achieved by hot melt coating.

Examples of the crosslinking agent include isocyanate, aziridine, and epoxy.

When the material forming the support is polyethylene terephthalate, it is preferable to use the various silicone-modified resins described above as the silicone resin, particularly silicone-modified polyurethane resins.

Preferably, silicone-modified acrylic resins are used; these have good adhesion to polyethylene terephthalate and are heat-fusible when the hot-fusible colorant layer detailed below is applied over the anchor layer. This is because the colorant layer composition is not repelled and production stability can be improved.

The content of the silicone resin in the anchor layer is usually in the range of 1 to 100% by weight, preferably 10% by weight.
It is within the range of 80% by weight. Note that if the content of the silicone resin in the anchor layer is high, the so-called repelling of the hot-melt coloring material layer coating liquid occurs when the hot-melting coloring material layer coating liquid is applied onto the anchor layer. Coating repellency may occur. In such a case, by adjusting the surface tension of the heat-fusible colorant layer coating solution, the occurrence of the coating repellency can be prevented.

In the thermal transfer recording medium of the present invention, the anchor layer may contain a filler together with the silicone resin.

For example, as shown in Figure 2 (a) and (b),
By adding the filler 4 to the anchor layer 2 and making the anchor layer 2 and the heat-melting coloring material layer 3 adjacent to each other, the filler 4 is added to the interface between the heat-melting coloring material layer 3 and the anchor layer 2. Fine unevenness 5 can be formed according to the particle size. In addition, in FIG. 2(b), 10 is a transfer medium.

The unevenness has the effect of removing the gloss on the surface of the heat-melting coloring material layer transferred to the transfer medium, that is, the surface of the printed image, and improving the difficulty in reading the printed image caused by the gloss.

Examples of the filler include silica, talc, calcium carbonate, carbon black, alumina, acid clay, clay, magnesium carbonate, tin oxide, titanium white,
Graphite, thermosetting resin particles, fluororesin particles, melamine resin particles, urea resin particles, benzoguanamine resin particles, acrylic resin particles, styrene resin particles, boron nitride, copper,
Examples include iron, aluminum, iron oxide, tin oxide, aluminum oxide, magnesium oxide, and titanium nitride.

Among these, carbon black is preferred when the heat-fusible coloring material layer is black. This is because by adding carbon black to make the anchor layer black, the secrecy of the thermal transfer recording medium of the present invention can be improved. That is, after the heat-melting coloring material layer is peeled off from the interface with the anchor layer, a so-called white area corresponding to the peeled portion of the heat-melting coloring material layer is generated in the anchor layer remaining on the support. This is because white areas can prevent the transferred recording content from being revealed from the copy.

However, when the heat-fusible coloring material layer is black, the above effects are not limited to the above-mentioned carbon black; for example, the above-mentioned black pigment that does not function as a filler may be used. You can also use Furthermore, when the heat-melting coloring material layer is of a color other than black, a pigment having a color similar to that of the heat-melting coloring material layer may be used.

The average particle size of the filler is usually 0.21 Am or more.
It is within the range below ILm.

Preferably, the anchor layer further contains other components such as wax.

The wax has the function of adjusting the adhesive force between the anchor layer and the heat-melting coloring material layer, which will be described in detail below.

The waxes include, for example, vegetable waxes such as carnauba wax, wood wax, auriculie wax, and Nispar wax; animal waxes such as beeswax, insect wax, shellac wax, and spermaceti wax; paraffin wax, microcrystal wax, polyethylene wax, ester wax, and acid wax. Examples include petroleum waxes such as wax; mineral waxes such as montan wax, osikerite, and ceresin.

When using the wax, the content of the wax in the anchor layer is usually 98% by weight or less, preferably 80% by weight or less.

In this invention, the anchor layer containing the above components is formed on the support by, for example, a coating method using an organic solvent.

The thickness of the anchor layer is usually in the range of 0.05 to 3 #Lm, preferably in the range of 0.1 to 1.5 pm.

A heat-melting coloring material layer, which will be described next, is usually laminated adjacent to this anchor layer.

- Heat-melting coloring material layer - The heat-melting coloring material layer usually contains a coloring material, a heat-melting substance, and a thermoplastic resin.

The layer thickness of this heat-melting coloring material layer is usually 0.5 to 8 ILm.
within the range, preferably 1.0 to 6.0 JLI
It is within the range of II.

Examples of the coloring material include pigments such as inorganic pigments and organic pigments, and dyes.

Examples of the inorganic pigments include titanium dioxide, carbon black, lead oxide, Prussian blue, cadmium sulfide, iron oxide, and chromates of lead, zinc, barium, and calcium.

Examples of the organic pigments include azo, thioindigo, anthraquinone, anthanthrone, and triphenedioxazine pigments, vat dye pigments, phthalocyanine pigments, such as copper phthalocyanine and its derivatives, and quinacridone pigments.

Examples of serious organic dyes include acid dyes, direct dyes, disperse dyes, oil-soluble dyes, and metal-containing oil-soluble dyes.

The content of the coloring material in the heat-melting coloring material layer is usually 5.
-35% by weight, preferably 10-25% by weight.

Specific examples of the heat-melting substances include plant waxes such as carnauba wax, wood wax, auriculie wax, and Nispar wax; animal waxes such as beeswax, insect wax, shellac wax, and spermaceti wax; paraffin wax, microcrystal wax, and polyethylene wax. , petroleum waxes such as ester waxes and acid waxes; and waxes such as mineral waxes such as montan wax, osichelite and ceresin; in addition to these waxes, palmitic acid, stearic acid, margaric acid, etc. and higher fatty acids such as behenic acid; higher alcohols such as valmityl alcohol, stearyl alcohol, behenyl alcohol, marganyl alcohol, myricyl alcohol and eicosanol; higher fatty acids such as cetyl palmitate, myricyl palmitate, cetyl stearate and myricyl stearate. Esters; amides such as acetamide, propionic acid amide, palmitic acid amide, stearic acid amide and amide wax; and higher amines such as stearylamine, behenylamine and palmitylamine.

These may be used alone or in combination of two or more.

Among these, preferred is a wax whose melting point is within the range of 50 to 100°C as measured using Yanagimoto MJP-2.

The thermoplastic resins include ethylene copolymers, polyamide resins, polyester resins, polyurethane resins, polyolefin resins, acrylic resins, vinyl chloride resins, cellulose resins, rosin resins, ionomer resins, and petroleum resins. Resins such as natural rubber, styrene butadiene rubber, isoprene rubber, chloroprene rubber, ethylene acrylate rubber, etc. Elastomers: ester gum, rosin maleic acid resin.

Examples include rosin derivatives such as rosin phenol resins and hydrogenated rosins; and polymeric compounds having a softening point of 50 to 150°C such as phenol resins, terpene resins, cyclopentadiene resins, and aromatic hydrocarbon resins.

These may be used alone or in combination of two or more.

In addition to the above-mentioned components, the heat-melting coloring material layer may contain a surfactant such as a polyoxyethylene chain-containing compound in order to adjust releasability.

The inclusion of the heat-melting substance in the heat-melting coloring material layer is as follows:
The amount is usually 50% by weight or more, preferably from 50 to 97% by weight, based on the total weight of the thermofusible substance and thermoplastic resin contained in this layer.

More preferably, it is within the range of 60 to 95% by weight.

If the content of the heat-fusible substance to the total weight of the heat-fusible substance and the thermoplastic resin is less than 50% by weight, releasability may deteriorate.

Furthermore, inorganic or organic fine particles (metal powder, silica gel, etc.) or oils (linseed oil, mineral oil, etc.) can also be added.

The heat-melt coloring material layer can be formed by hot-melt coating method, water-based coating method,
Coating can be done using a coating method using an organic solvent, but in this invention.

The coating is usually applied using a hot melt coating method.

-Others- The heat-sensitive transfer recording medium of the present invention may have a heat-softening layer between the anchor layer and the heat-melting coloring material layer.

The heat-softening layer is usually a layer made of the above-mentioned thermoplastic resin and a heat-melting substance, and the thickness of the layer is usually 0.6.
~8. OILm is within the range, preferably 1.0 to 6
．． It is in the range of OILm.

The thermosoftening layer is preferably applied by a method of preparing an aqueous emulsion containing a thermofusible substance and a thermoplastic resin, and performing aqueous coating using this aqueous emulsion.

The aqueous emulsion can be applied by employing known methods such as a coating method using a wire bar, a gravure coating method, a kiss coating method, and a calendar coating method.

When water is removed from the applied aqueous emulsion, the particles constituting the emulsion (thermally softenable layer forming component particles) remain as they are or in a similar form (
For example, the heat-softening layer is composed of crushed spherical particles, and each particle is adhered to each other at a point or surface where it contacts an adjacent particle. Therefore, during thermal transfer, these spherical or similar particles act independently to some extent to provide good print quality.

Moreover, an overcoat layer can also be laminated on the heat-melting coloring material layer.

After each layer is coated in this manner, it is optionally subjected to a drying process, a surface smoothing process, etc., and then cut into a desired shape to obtain the thermal transfer recording medium of the present invention.

The thermal transfer recording medium thus obtained can be used in the form of a wide tape or typewriter ribbon generally used in line printers, etc., but the planar shape of the thermal transfer recording medium of the present invention is A sheet having the same width as the recording paper used in line printers is preferable.

The heat-sensitive transfer method using this heat-sensitive transfer recording medium is not different from a normal heat-sensitive transfer recording method, but will be explained using an example in which the most typical thermal head is used as a heat source.

First, the heat-melting coloring material layer of the heat-sensitive transfer recording medium and the medium to be transferred, such as transfer paper, are brought into close contact with each other, and if necessary, a heat pulse is further applied from the back side of the transfer paper using a platen.
A heat pulse is applied by a thermal head to locally heat the heat-melting coloring material layer corresponding to a desired printing or transfer pattern.

The temperature of the heated portion of the heat-melting coloring material layer increases, and the heat-melting coloring material layer is quickly softened and transferred onto the transfer medium.

[Example] Next, Examples and Comparative Examples of the present invention will be shown to further specifically explain the present invention.

(Example 1) The following anchor layer composition was diluted with a solvent with a volume ratio of (methyl ethyl ketone):(toluene) of 1:l and applied as an anchor layer on a polyethylene terephthalate film with a thickness of 4.5 p and m. A liquid (solid content concentration 20%) was prepared.

Next, this anchor layer coating liquid was applied over a length corresponding to the width of JIS standard A4 paper to a layer thickness of 0.8 #Lm to form an anchor layer in the thermal transfer recording medium of the present invention.

Silicone-modified urethane resin: 50% by weight (silicone content: 20% by weight) Polyester: 50% by weight [Manufactured by Toyobo ■: "Vylon 200J"] Next, the following hot-melt coloring material layer composition was applied to a film thickness of 4.0.B using a wire bar.
A hot-melt coloring material layer was formed by hot-melt coating on the anchor layer so that the colorant had a thickness of m, thereby producing a heat-sensitive transfer recording medium of the present invention.

Paraffin wax: 50% by weight Carnauba wax: 23% by weight Carbon black: 15% by weight Ethylene ethyl acrylate: 14% by weight % The obtained thermal transfer recording medium was transferred to a thermal printer (260 ms width line head, 1
80 DPI, platen rubber hardness 40 degrees),
Recording (printing) was performed on plain paper (Beck smoothness: 50 seconds), and the print quality, peeling sound, and gloss of the printed image were evaluated.

The results are shown in Table 1.

Note that printing quality, peeling sound, and glossiness were each evaluated as follows.

Print quality: Voids and sharpness were visually observed.

Peeling sound: The presence or absence of peeling sound during printing was confirmed by hearing.

Glossiness: Using a glossmeter, the glossiness of the printed image was measured under the condition that both the incident angle and the reflection angle were 60°.

(Example 2) Example 1 was carried out in the same manner as in Example 1, except that the following anchor layer composition was used in place of the anchor layer composition in Example 1.

The results are shown in Table 1.

Anchor silicone modified acrylic resin...50% by weight [Manufactured by Toagosei Chemical ■: "Front US,"] Titanium White...
......50% by weight [average particle size 1. OILm] (Comparative Example 1) A thermal transfer recording medium was produced in the same manner as in Example 1, except that the anchor layer was not formed, and the printed image on the obtained thermal transfer recording medium was Print quality, peeling sound and glossiness were evaluated.

The results are shown in Table 1.

(Comparative Example 2) In Example 2, polyester [manufactured by Toyobo ■: [Vylon ZOOJ] was used instead of the silicone-modified acrylic resin of the anchor layer composition in Example 2, except that A thermal transfer recording medium was produced in the same manner, and the print quality, peeling sound, and gloss of the printed image were evaluated for the obtained thermal transfer recording medium.

The results are shown in Table 1.

(Tree pages, blank spaces below) Table 1 The symbols for each evaluation item are the following: a taste.

Print quality: O゛: Both voids and sharpness are good.

×: Both void and sharpness are written. inferior in quality.

Peeling sound: O: Clear peeling sound cannot be heard.

X: A clear peeling sound can be heard.

(Evaluation) As is clear from Table 1, compared to the thermal transfer recording media of Comparative Examples 1 and 2, the thermal transfer recording medium of the present invention has excellent print quality of printed images, and almost no peeling sound occurs. I confirmed that it does not.

Furthermore, as in Example 2, when the anchor layer contains a filler, it is possible to improve print quality and reduce peeling sound, while also achieving a printed image with low gloss on one surface and easy to read. It was also confirmed that Therefore, in the thermal transfer recording medium/body of the present invention, the surface gloss of the printed image can be reduced by containing a filler in the anchor layer depending on the intended use.

In any case, in the thermal transfer recording medium of the present invention, it is possible to improve print quality and reduce peeling noise.

[Effects of the Invention] According to the present invention, (1) An anchor layer containing a silicone tree and realizing interfacial separation with the heat-melting coloring material layer is provided between the support and the heat-melting coloring material layer. (2) Therefore, the print quality of the printed image is high; (3)
In addition, there is almost no peeling sound when the heat-melting coloring material layer is peeled off. Provided is a thermal transfer recording medium that has various advantages such as forming fine irregularities on the surface of a coloring material layer and removing gloss on the surface of the printed image to obtain an easily readable printed image. can do.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram showing an example of the thermal transfer recording medium of the present invention, FIG. 2 (A) is a cross-sectional explanatory diagram showing another example, and FIG. FIG. 2 is an explanatory cross-sectional view showing a cross section of a printed image obtained by the thermal transfer recording medium of FIG. 1...Support, 2...Anchor layer, 3...Thermofusible coloring material layer.

Claims (1)

[Claims] (1) A heat-sensitive transfer recording medium characterized by having an anchor layer containing a silicone resin between the support and the heat-melting coloring material layer.