JP7616563B2 - Peel-off sheet, combination of said peel-off sheet and intermediate transfer medium, and method for producing printed matter using said combination - Google Patents

Description

This disclosure relates to a peel-off sheet, a combination of the peel-off sheet with an intermediate transfer medium, and a method for producing a print using the combination.

As proposed in Patent Document 1, an intermediate transfer medium is used as a means for forming a print without being restricted on a transferee. This intermediate transfer medium is a substrate on which a transfer layer including a receptive layer is provided in a peelable manner. With such an intermediate transfer medium, a thermal transfer image is formed on the receptive layer of the intermediate transfer medium using a thermal transfer sheet having a color material layer, and then the transfer layer including the receptive layer is transferred onto any transferee, thereby obtaining a print on which a thermal transfer image is formed on any transferee. In particular, intermediate transfer media are used for transferees on which the color material is difficult to transfer and on which a high-quality image cannot be directly formed, and transferees on which the color material layer is easily fused during thermal transfer.

There are various types of prints that can be obtained by transferring the transfer layer of an intermediate transfer medium onto a receiving body. For example, in the case of printed matter such as IC cards, it is necessary to leave areas for the IC chip, magnetic stripe, transmitting/receiving antenna, signature, etc., and there may be areas on the surface of the receiving body that would be inconvenient to be covered with the transfer layer. In other words, there are cases where the surface of the receiving body needs to be exposed.

Under such circumstances, attempts have been made to use a thermal transfer sheet with a peel-off layer on one side of the substrate, and before transferring the transfer layer of the intermediate transfer medium onto the transferee, remove a predetermined area of the transfer layer, for example, an area of the transfer layer that is not desired to be transferred to the transferee, with the peel-off layer (hereinafter also referred to as "peel-off"). For example, Patent Document 2 proposes a method in which the peel-off layer of the thermal transfer sheet and the transfer layer of the intermediate transfer medium are overlapped so that they are in contact with each other, and then energy is applied from the other side of the substrate of the thermal transfer sheet, and a predetermined area of the transfer layer corresponding to the area to which energy has been applied is removed with the peel-off layer. In the thermal transfer sheet of Patent Document 2, for example, polyester is used for the peel-off layer.

JP 2014-80016 A JP 2003-326865 A

In recent years, in response to demands for cost reduction, attempts have been made to reduce the thickness of the substrate in thermal transfer sheets with peel-off properties (hereinafter also referred to as "peel-off sheets"). Also, in order to improve the productivity of printed matter, attempts have been made to increase the printing energy during peel-off and to speed up peel-off.

Recently, the inventors noticed that when they tried to increase the peel-off speed by using a peel-off sheet with a thin film substrate, the peel-off sheet could break during peel-off.

Means for Solving the Problems The present inventors conducted studies to solve the above problems and discovered that the breakage of the peel-off sheet is related to the glass transition temperature of the polyester constituting the peel-off layer, and that breakage of the peel-off sheet can be suppressed by using a layer composed of a polyester having a high glass transition temperature.
However, in a peel-off sheet having such a peel-off layer, a new problem occurs in that the peel-off properties are deteriorated.

The present disclosure has been made in light of the above findings, and an object of the present disclosure is to provide a peel-off sheet that can suppress breakage even when a thin film substrate is used, and has excellent peel-off performance.
It is an object of the present disclosure to provide a combination of said peel-off sheet and an intermediate transfer medium.
An object of the present disclosure is to provide a method for producing a print using the combination.

The present disclosure provides a peel-off sheet comprising a first substrate and a peel-off layer located on one surface side of the first substrate,
the peel-off layer comprises a first polyester and a second polyester;
The glass transition temperature of the first polyester is 80° C. or more and 120° C. or less,
The glass transition temperature of the second polyester is 40° C. or more and 70° C. or less,
The peel-off sheet has a ratio of the mass of the second polyester to the mass of the first polyester of 0.05 or more and 0.8 or less.

The present disclosure provides a combination of a peel-off sheet and an intermediate transfer medium, comprising:
The peel-off sheet is a peel-off sheet according to the present disclosure,
The intermediate transfer medium is a combination of a peel-off sheet and an intermediate transfer medium, comprising a second substrate and a transfer layer located on one side of the second substrate, the transfer layer comprising a receiving layer, the receiving layer being the outermost layer of the intermediate transfer medium.

The present disclosure provides a method for producing a peel-off sheet and intermediate transfer medium combination, comprising:
a step of bonding the receiving layer and the peel-off layer by heating and pressing in at least a part of the removal area of the intermediate transfer medium, and then peeling off the transfer layer provided in the removal area from the intermediate transfer medium;
and transferring the transfer layer in the non-removal area from the intermediate transfer medium onto a recipient.

According to the present disclosure, even when a thin substrate is used, it is possible to provide a peel-off sheet that can suppress breakage and has excellent peel-off performance.
According to the present disclosure, a combination of the peel-off sheet and an intermediate transfer medium can be provided.
According to the present disclosure, a method for producing a print using the combination can be provided.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a peel-off sheet according to the present disclosure. FIG. 1 is a schematic cross-sectional view showing one embodiment of a peel-off sheet according to the present disclosure. 1 is a schematic cross-sectional view illustrating one embodiment of a peel-off sheet and intermediate transfer medium combination according to the present disclosure. FIG. 2 is a schematic diagram for explaining a method for producing a printed matter according to the present disclosure.

[Peel-off sheet]
The peel-off sheet according to the present disclosure comprises a first substrate and a peel-off layer located on one surface side of the first substrate.
In one embodiment, the peel-off sheet according to the present disclosure may include a primer layer between the first substrate and the peel-off layer. The primer layer may be adjacent to the first substrate and the peel-off layer.

Below, one embodiment of a peel-off sheet according to the present disclosure is described with reference to the drawings.

In one embodiment, the peel-off sheet 10 is composed of a first substrate 11 and a peel-off layer 12 located on one side of the first substrate 11, as shown in FIG. 1.

In one embodiment, as shown in FIG. 2, the peel-off sheet 10 is composed of a first substrate 11, a primer layer 13, and a peel-off layer, in that order. That is, the primer layer 13 is located between the first substrate 11 and the peel-off layer 12. The primer layer 13 is adjacent to the first substrate 11 and the peel-off layer 12.

In one embodiment, the peel-off sheet 10 may include a colorant layer (not shown) in face sequence with the peel-off layer 12. When the peel-off sheet 10 includes a colorant layer, the peel-off sheet may include at least one layer (not shown) selected from the group consisting of a primer layer, a release layer, and a release layer between the first substrate 11 and the colorant layer.
In one embodiment, the peel-off sheet 10 may have a back layer on the other side of the first substrate 11, i.e., the side opposite the peel-off layer 12 located on one side of the first substrate 11 (not shown).

The layer structure of the peel-off sheet 10 described above can be combined as appropriate.

Below, we will explain each layer that the peel-off sheet according to this disclosure may have.

<First substrate>
The first substrate can be used without particular restrictions as long as it has heat resistance sufficient to withstand the thermal energy (e.g., heat from a thermal head) applied when peeling off the transfer layer of the intermediate transfer medium, and has mechanical strength and solvent resistance sufficient to support each layer such as the peel-off layer.
Examples of the first substrate include polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), 1,4-polycyclohexylene dimethylene terephthalate, and terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymers; polyamides such as nylon 6 and nylon 6,6; polyolefins such as polyethylene (PE), polypropylene (PP), and polymethylpentene; polyvinyl chloride, polyvinyl alcohol (PVA), polyvinyl acetate, vinyl chloride-vinyl acetate copolymers, polyvinyl butadiene, and the like. Films (hereinafter simply referred to as "resin films") made of resin materials such as vinyl resins such as polyvinylpyrrolidone (PVP), (meth)acrylic resins such as polyacrylate, polymethacrylate, and polymethyl methacrylate, imide resins such as polyimide and polyetherimide, cellulose resins such as cellophane, cellulose acetate, nitrocellulose, cellulose acetate propionate (CAP), and cellulose acetate butyrate (CAB), styrene resins such as polystyrene (PS), polycarbonate, and ionomer resins can be used.
Among the above-mentioned resin materials, polyester is preferable, and PET is particularly preferable, from the viewpoints of heat resistance and mechanical strength.
In the present disclosure, "(meth)acrylic" refers to both "acrylic" and "methacrylic", and "(meth)acrylate" refers to both "acrylate" and "methacrylate".

The first substrate may be a laminate in which the above-mentioned resin film is laminated. The laminate can be produced by using a dry lamination method, a wet lamination method, an extrusion method, or the like.

The resin film may be a stretched film or an unstretched film. From the viewpoint of strength, the resin film is preferably a stretched film that is uniaxially or biaxially stretched.

The thickness of the first substrate is preferably 1 μm or more, more preferably 3 μm or more, while the thickness of the first substrate is preferably less than 6 μm, more preferably 5.5 μm or less, and even more preferably 4.5 μm or less.
By setting the thickness of the first substrate to 1 μm or more, the mechanical strength of the peel-off sheet can be improved.
By setting the thickness of the first substrate to less than 6 μm, the transfer of thermal energy during thermal transfer in the peel-off sheet can be improved, and the production cost of the peel-off sheet can be further improved.

The surface of the first substrate may be subjected to an adhesive treatment in order to improve adhesion with other layers. That is, a first substrate that has been subjected to an adhesive treatment may be used as the first substrate of the peel-off sheet. Examples of the adhesive treatment include known resin surface modification techniques such as corona discharge treatment, flame treatment, ozone treatment, ultraviolet treatment, radiation treatment, roughening treatment, chemical treatment, plasma treatment, low-temperature plasma treatment, and grafting treatment. Two or more of these adhesive treatments may be used in combination.

<Peel-off layer>
In this specification, the peel-off layer is a layer for peeling off the transfer layer provided on the intermediate transfer medium.
In the peel-off sheet according to the present disclosure, the peel-off layer comprises a first polyester and a second polyester. The first polyester has a glass transition temperature (hereinafter also referred to as "Tg") of 80° C. or more and 120° C. or less. The second polyester has a Tg of 40° C. or more and 70° C. or less. In the peel-off layer, the ratio ( _W2 / _W1 ) of the mass ( _W1 ) of the second polyester to the mass ( _W2 ) of the first polyester is 0.05 or more and 0.8 or less.
The peel-off sheet according to the present disclosure, by being provided with the above-mentioned peel-off layer, can suppress breakage even when a thin substrate is used, and has excellent peel-off properties. The mechanism by which such effects are obtained is not necessarily clear at present, but it is clear from the results of the examples and comparative examples described later that the peel-off sheet has excellent break resistance and peel-off properties by forming a peel-off layer containing a first polyester having a high Tg and a second polyester having a low Tg, and the mass ratio of these polyesters is within a specific range.

From the viewpoint of the breaking resistance of the peel-off sheet, the Tg of the first polyester is preferably 85° C. or more, more preferably 90° C. or more. On the other hand, the Tg of the first polyester may be 110° C. or less.
In this specification, Tg is a value determined by differential scanning calorimetry (DSC) in accordance with JIS K 7121:2012.

In the range where _W2 / _W1 is 0.05 or more and 0.8 or less, the content of the first polyester is, from the viewpoint of the breakage resistance of the peel-off sheet, preferably 45 mass% or more, more preferably 60 mass% or more, and even more preferably 70 mass% or more, based on the total solid content in the peel-off layer. On the other hand, the content of the first polyester is, for example, 95 mass% or less, or may be 90 mass% or less, or may be 85 mass% or less, based on the total solid content in the peel-off layer.

The number average molecular weight (hereinafter also referred to as "Mn") of the first polyester is, for example, 10,000 or more, and may be 12,000 or more. On the other hand, the Mn of the first polyester is, for example, 30,000 or less, and may be 20,000 or less.
In this specification, Mn means a value measured by gel permeation chromatography using polystyrene as a standard substance, and is measured by a method in accordance with JIS K 7252-3:2016.

From the viewpoint of the peel-off properties of the peel-off sheet, the Tg of the second polyester is preferably 68°C or less. On the other hand, the Tg of the second polyester may be 50°C or more.

In the range where _W2 / _W1 is 0.05 or more and 0.8 or less, the content of the second polyester is, from the viewpoint of the peel-off property of the peel-off sheet, preferably 3 mass% or more, more preferably 5 mass% or more, and even more preferably 10 mass% or more, based on the total solid content in the peel-off layer. On the other hand, the content of the second polyester is, for example, 35 mass% or less, or may be 30 mass% or less, or may be 20 mass% or less, based on the total solid content in the peel-off layer.

The Mn of the second polyester is preferably not less than 5,000, and more preferably not less than 10,000. By making the Mn of the second polyester not less than 5,000, the polymers in the peel-off layer are intricately entangled with each other, and as a result, cohesive failure of the peel-off layer during peel-off can be suppressed, and the peel-off properties can be further improved.
On the other hand, the Mn of the second polyester is, for example, 50,000 or less, and may be 30,000 or less.

_W2 / _W1 is preferably _0.1 or more, and more preferably 0.2 or more, whereas W2/ _W1 is preferably 0.65 or less, and more preferably 0.5 or less, and even more preferably 0.3 or less.
By making W ₂ /W ₁ 0.1 or more, the peel-off property of the peel-off sheet can be further improved.
On the other hand, by setting W ₂ /W ₁ to 0.65 or less, the breakage resistance of the peel-off sheet can be further improved.

In one embodiment, the peel-off layer preferably contains particles. By including particles in the peel-off layer, the blocking resistance of the peel-off sheet can be improved. The particles may be organic particles, inorganic particles, or a combination thereof.

Examples of organic particles include particles (resin particles) made of resins such as melamine resin, benzoguanamine resin, (meth)acrylic resin, polyamide, fluororesin, phenolic resin, styrene resin, polyolefin, silicone resin, and copolymers of monomers that make up these resins.

Inorganic particles include clay minerals such as talc and kaolin, carbonates such as calcium carbonate and magnesium carbonate, hydroxides such as aluminum hydroxide and magnesium hydroxide, sulfates such as calcium sulfate, oxides such as silica, graphite, saltpeter, and boron nitride.

The shape of the particles may be any of irregular, spherical, elliptical, cylindrical, and prismatic. The surface of the particles may be treated with a surface treatment agent such as a silane coupling agent.

The average particle size of the particles is preferably 5 μm or less, and more preferably 3 μm or less. By setting the average particle size of the particles to 5 μm or less, the smoothness of the surface of the peel-off layer can be maintained, and the peel-off property can be improved.
On the other hand, the average particle size of the particles is, for example, 0.5 μm or more.
In this specification, the average particle size means the volume average particle size and is measured in accordance with JIS Z 8819-2:2019.

The content of the particles is preferably 1% by mass or more, more preferably 3% by mass or more, based on the total solid content in the peel-off layer, while the content of the particles is preferably 10% by mass or less, more preferably 7% by mass or less, based on the total solid content in the peel-off layer.
By setting the particle content to 1% by mass or more, the blocking resistance of the peel-off sheet can be improved.
On the other hand, by setting the particle content to 10% by mass or less, the adhesion of the peel-off layer to the transfer layer of the intermediate transfer medium can be improved, and the peel-off properties of the peel-off sheet can be improved.

The peel-off layer may contain one or more additives such as fillers, plasticizers, UV absorbers, and dispersants, to the extent that the properties of the peel-off sheet according to the present disclosure are not impaired.

Since the peel-off layer contains polyester, it has particularly excellent adhesion to layers containing polyester. Therefore, the peel-off sheet according to the present disclosure can be suitably used in intermediate transfer media having a layer containing polyester as the outermost layer. The outermost layer of the intermediate transfer medium is, for example, a receiving layer on which an image is formed by printing the color material layer. When the outermost layer of the intermediate transfer medium is a receiving layer, the receiving layer preferably contains polyester and a vinyl chloride-vinyl acetate copolymer from the viewpoints of adhesion to the peel-off layer and suitability for printing.

The peel-off layer can be formed by dispersing or dissolving the above-mentioned materials in water or a suitable solvent to prepare a coating liquid, and applying the coating liquid onto the first substrate or a primer layer, etc., by known means such as roll coating, reverse roll coating, gravure coating, reverse gravure coating, bar coating, or rod coating to form a coating film, which is then dried.

<Primer layer>
In one embodiment, the peel-off sheet may have a primer layer between the first substrate and the peel-off layer. By adopting such a configuration, it is possible to improve the adhesion between the first substrate and the primer layer, and to suppress the phenomenon in which the peel-off layer that should remain moves to the intermediate transfer medium side, that is, the so-called reverse transfer phenomenon of the peel-off layer. In particular, when the printing energy is high, the reverse transfer of the peel-off layer tends to occur easily, so a peel-off sheet having a primer layer is preferable.
In one embodiment, when the colorant layer described below is a sublimation transfer type colorant layer, the peel-off sheet may include a primer layer between the colorant layer and the first substrate.

The primer layer may contain one or more resin materials. Examples of the resin materials contained in the primer layer include polyester, vinyl resin, polyurethane, (meth)acrylic resin, polyamide, polyether, styrene resin, and cellulose resin. Among these, the resin material is preferably polyester from the viewpoint of adhesion between the first substrate and the peel-off layer.

The primer layer may contain the above additives.

The thickness of the primer layer is, for example, 0.05 μm or more and 2.0 μm or less.

The primer layer can be formed by dispersing or dissolving the above-mentioned materials in a suitable solvent to prepare a coating liquid, applying the liquid to the first substrate or the like using the above-mentioned coating means to form a coating film, and then drying the coating film.

<Colorant Layer>
The color material layer is a layer for forming an image on a receiving layer or the like of the intermediate transfer medium. The color material layer may be a sublimation transfer type color material layer in which only the sublimation dye contained in the color material layer is transferred, or a melt transfer type color material layer in which the color material layer itself is transferred. The peel-off sheet may have both a sublimation transfer type color material layer and a melt transfer type color material layer as the color material layer.

The colorant layer contains one or more colorants. The colorant may be a pigment or a dye. The dye may be a sublimable dye.
Examples of the coloring material contained in the coloring material layer include carbon black, acetylene black, lamp black, black smoke, iron black, aniline black, silica, calcium carbonate, titanium oxide, cadmium red, cadmium phosphate red, chrome red, vermilion, red iron oxide, azo pigments, alizarin lake, quinacridone, cochineal lake perylene, yellow ocher, aureolin, cadmium yellow, cadmium orange, chrome yellow, zinc yellow, Naples yellow, nickel yellow, azo pigments, greenish yellow, ultramarine, rock ultramarine, cobalt, phthalocyanine, anthraquinone, and iridium. pigments such as cadmium green, cinnabar green, cadmium green, chrome green, phthalocyanine, azomethine, perylene and aluminum pigments; and dyes such as diarylmethane dyes, triarylmethane dyes, thiazole dyes, merocyanine dyes, pyrazolone dyes, methine dyes, indoaniline dyes, acetophenone azomethine dyes, pyrazoloazomethine dyes, xanthene dyes, oxazine dyes, thiazine dyes, azine dyes, acridine dyes, azo dyes, spiropyran dyes, indolinospiropyran dyes, fluoran dyes, naphthoquinone dyes, anthraquinone dyes and quinophthalone dyes.

The colorant layer may contain one or more resin materials. Examples of resin materials contained in the colorant layer include polyester, polyamide, polyolefin, vinyl resin, vinyl acetal resin, (meth)acrylic resin, cellulose resin, styrene resin, polycarbonate, butyral resin, phenoxy resin, and ionomer resin.

The colorant layer may contain the above additives.

The thickness of the color material layer is, for example, 0.1 μm or more and 3 μm or less.

The colorant layer can be formed by dispersing or dissolving the above-mentioned materials in a suitable solvent to prepare a coating liquid, applying the liquid to the first substrate, primer layer, peeling layer or release layer, etc., using the above-mentioned coating means to form a coating film, and then drying the coating film.

<Release Layer>
When the colorant layer is a melt-transfer type colorant layer, the peel-off sheet may have a release layer between the first substrate and the colorant layer. The release layer is a layer that is transferred from the peel-off sheet to an intermediate transfer medium or the like by heating. By positioning the release layer between the first substrate and the colorant layer, the transferability of the colorant layer can be improved.

The release layer may contain one or more resin materials. Examples of the resin materials contained in the release layer include polyester, polyamide, polyolefin, vinyl resin, (meth)acrylic resin, imide resin, cellulose resin, styrene resin, polycarbonate, and ionomer resin.

The resin material content in the release layer is, for example, 50% by mass or more and 99% by mass or less.

The release layer may contain the additives described above.

The thickness of the peeling layer is, for example, 0.1 μm or more and 3 μm or less.

The release layer can be formed by dispersing or dissolving the above-mentioned materials in an appropriate solvent to prepare a coating liquid, applying the coating liquid onto the first substrate or release layer, etc., using the above-mentioned coating means to form a coating film, and then drying the coating film.

<Release Layer>
When the colorant layer is a melt-transfer type colorant layer, the peel-off sheet may have a release layer between the first substrate and the colorant layer, or between the first substrate and the peeling layer. The release layer is a layer that remains on the first substrate on the peel-off sheet side during thermal transfer, i.e., a non-transfer layer. By positioning the release layer between the first substrate and the colorant layer, or between the first substrate and the peeling layer, the transferability of the colorant layer and the peeling layer can be improved.

The release layer may contain one or more resin materials. Examples of the resin materials contained in the release layer include (meth)acrylic resin, polyurethane, acetal resin, polyamide, polyester, melamine resin, polyol resin, cellulose resin, and silicone resin.

The release layer may contain one or more types of release materials. Examples of release materials include fluorine compounds, phosphate ester compounds, silicone oils, higher fatty acid amide compounds, metal soaps, and waxes such as paraffin wax.

The content of the release material in the release layer is, for example, 0.1% by mass or more and 10% by mass or less.

The release layer may contain the additives described above.

The thickness of the release layer is, for example, 0.1 μm or more and 2.0 μm or less.

The release layer can be formed by dispersing or dissolving the above-mentioned materials in a suitable solvent to prepare a coating liquid, applying the liquid to the first substrate or the like using the above-mentioned coating means to form a coating film, and then drying the coating film.

<Back layer>
The back layer is a layer provided to prevent sticking and wrinkling caused by heating during thermal transfer.

The back layer contains one or more resin materials. Examples of the resin materials contained in the back layer include vinyl resin, polyester, polyamide, polyolefin, (meth)acrylic resin, polyolefin, polyurethane, cellulose resin, and phenolic resin.

The back layer may contain at least one isocyanate compound. Examples of the isocyanate composition contained in the back layer include xylylene diisocyanate, toluene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate.

The back layer may contain the above additives.

The thickness of the back layer is, for example, 0.01 μm or more and 3.0 μm or less.

The back layer can be formed by dispersing or dissolving the above-mentioned materials in an appropriate solvent to prepare a coating liquid, applying the liquid to the first substrate or the like using the above-mentioned coating means to form a coating film, and then drying the coating film.

[Combination of Peel-Off Sheet and Intermediate Transfer Medium]
In a combination of a peel-off sheet and an intermediate transfer medium according to the present disclosure, the peel-off sheet is a peel-off sheet according to the present disclosure, the intermediate transfer medium comprises a second substrate and a transfer layer located on one side of the second substrate, the transfer layer comprises a receiving layer, and the receiving layer is the outermost layer of the intermediate transfer medium.

Below, one embodiment of a combination of a peel-off sheet and an intermediate transfer medium according to the present disclosure is described with reference to the drawings.

In one embodiment, the combination of the peel-off sheet 10 and the intermediate transfer medium 20 includes the peel-off sheet 10 having a first substrate 11 and a peel-off layer 12 located on one side of the first substrate 11, and the intermediate transfer medium 20 having a second substrate 21 and a transfer layer 23, as shown in FIG. 3. The transfer layer 23 includes a receiving layer 22. The receiving layer 22 is the outermost layer of the intermediate transfer medium 20.

In one embodiment, the transfer layer 23 of the intermediate layer medium 20 may include a release layer between the second substrate 21 and the receiving layer 22 (not shown).
In one embodiment, the intermediate transfer medium 20 may include a release layer (not shown) between the second substrate 21 and the receiving layer 22. When the intermediate transfer medium 20 includes a peeling layer and a release layer, the intermediate transfer medium 20 includes the second substrate 21, the release layer, the peeling layer, and the receiving layer 22 in this order.
In one embodiment, the transfer layer 23 of the intermediate transfer medium 20 may have a protective layer 26 between the second substrate 21 and the receiving layer 22 (not shown). When the transfer layer 23 of the intermediate transfer medium 20 has a release layer and a protective layer, the intermediate transfer medium 20 has, in this order, the second substrate 21, the release layer, the protective layer, and the receiving layer 22.

The layer configuration of the intermediate transfer medium 20 described above can be combined as appropriate.

Each layer that the intermediate transfer medium may have is described below. Note that a description of the peel-off sheet is omitted since it has been described above. Also, a description of the peel-off layer and release layer that the intermediate transfer medium may have is omitted since they are similar to the peel-off sheet.

<Second substrate>
The second substrate can be appropriately selected from the materials usable for the first substrate.

<Recipient layer>
The receiving layer is a layer on which an image is formed by printing the color material layer. The receiving layer is a layer that is transferred from the intermediate transfer medium to a transfer-receiving body or the like.

The receiving layer may contain one or more resin materials, such as polyolefin, vinyl resins such as polyvinyl chloride and vinyl chloride-vinyl acetate copolymers, (meth)acrylic resins, cellulose resins, polyesters, polyamides, polycarbonates, styrene resins, epoxy resins, polyurethanes, epoxy resins, and ionomer resins.
Since the peel-off layer of the peel-off sheet according to the present disclosure contains polyester, the receiving layer preferably contains polyester from the viewpoint of peel-off properties. From the viewpoints of adhesion to the peel-off layer and printability, the receiving layer preferably contains polyester and a vinyl chloride-vinyl acetate copolymer.

The content of the resin material in the receiving layer is preferably 50% by mass or more, more preferably 80% by mass or more, based on the total amount of solids in the receiving layer. By making the content of the resin material in the receiving layer 50% by mass or more, the peel-off properties can be further improved, and the image density can be further improved.

The receiving layer may contain the above-mentioned release material. This improves the releasability of the peel-off sheet from the color material layer, etc.

The receiving layer may contain an additive.

The thickness of the receiving layer is preferably 0.5 μm or more, and more preferably 1 μm or more. On the other hand, the thickness of the receiving layer is preferably 20 μm or less, and more preferably 10 μm or less. By making the receiving layer have such a thickness, the image density can be further improved.

The receiving layer can be formed by dispersing or dissolving the above-mentioned materials in a suitable solvent to prepare a coating liquid, applying the liquid to a second substrate or the like using the above-mentioned coating means to form a coating film, and then drying the coating film.

<Protective Layer>
The protective layer is a layer that is transferred from the intermediate transfer medium to a transfer receiving body or the like.

The protective layer may contain one or more resin materials. Examples of the resin materials contained in the protective layer include polyester, (meth)acrylic resin, epoxy resin, styrene resin, acrylic polyol resin, polyurethane, ionizing radiation curable resin, and ultraviolet absorbing resin.

The protective layer may contain an isocyanate compound. Examples of the isocyanate compound include xylylene diisocyanate, toluene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate.

The protective layer may contain the above additives.

The thickness of the protective layer is preferably 0.5 μm or more, and more preferably 1 μm or more. On the other hand, the thickness of the protective layer is preferably 7 μm or less, and more preferably 5 μm or less. By making the protective layer have such a thickness, the durability of the protective layer can be further improved.

The protective layer can be formed by dispersing or dissolving the above-mentioned materials in a suitable solvent to prepare a coating liquid, applying the liquid to a second substrate or the like using the above-mentioned coating means to form a coating film, and then drying the coating film.

[Method of manufacturing printed matter]
A method for producing a print according to the present disclosure will be described with reference to FIG.

The method for producing the print 30 according to the present disclosure includes:
preparing a combination of a peel-off sheet 10 and an intermediate transfer medium 20 (see 4(a));
a step of bonding the receiving layer 22 and the peel-off layer 12 by heating and pressing in at least a part of the removal area of the intermediate transfer medium 20, and then peeling off the transfer layer 23 provided in the removal area from the intermediate transfer medium 20 (see FIG. 4(b));
The method further includes a step of transferring the transfer layer 23 in the non-removal area from the intermediate transfer medium 20 onto the transfer recipient 31 (see FIG. 4C).
In this way, the print 30 can be produced (see FIG. 4(d)).

In one embodiment, the method for producing a print may include a step of forming an image on the receiving layer 22 before the peel-off step of the transfer layer 23, or after the peel-off step of the transfer layer 23 and before the transfer step of the transfer layer 23.

Below, we will explain each step that may be included in the method for producing printed matter according to this disclosure.

<Preparation of Peel-Off Sheet and Intermediate Transfer Medium>
The method for producing a print according to the present disclosure includes the steps of preparing a peel-off sheet and an intermediate transfer medium. The methods for producing the peel-off sheet and the intermediate transfer medium are as described above, and therefore will not be described here.

<Peel-off process>
The method for producing a print according to the present disclosure includes a step of peeling off a transfer layer provided in a removal area of an intermediate transfer medium.
In one embodiment, peel-off of the transfer layer provided in the removal area of the intermediate transfer medium can be carried out by overlapping the receiving layer of the intermediate transfer medium and the peel-off layer of the peel-off sheet in at least a portion of the removal area, then heating the peel-off sheet from the back layer side using a thermal head or the like and pressing them together, and peeling off the peel-off sheet.
In this step, the heat and pressure bonding between the transfer layer and the peel-off layer is preferably performed over the entire removal area, which allows the transfer layer provided in the removal area to be peeled off more accurately.

<Transfer process onto a transfer receiving body>
The method for producing a print according to the present disclosure includes a step of transferring the transfer layer in the non-removed area of the intermediate transfer medium onto a transfer recipient. The transfer can be performed by a conventional method using a commercially available thermal transfer printer.

The substrate to which the image is to be transferred is not particularly limited and can be appropriately selected depending on the application. Examples of substrates to which the image is to be transferred include paper substrates such as fine paper, art paper, coated paper, resin-coated paper, cast-coated paper, paperboard, synthetic paper, and impregnated paper, as well as the above-mentioned resin films.

<Image forming process>
The method for producing a print may include a step of forming an image on a receiving layer of an intermediate transfer medium. The image may be formed using a colorant layer of the peel-off sheet, or a separate thermal transfer sheet or the like having a colorant layer.
The image may be formed before or after peeling off the transfer layer.

Below is an embodiment of the peel-off sheet, the combination of the peel-off sheet and the intermediate transfer medium, and the method for producing a printed matter according to the present disclosure. Note that the peel-off sheet, the combination of the peel-off sheet and the intermediate transfer medium, and the method for producing a printed matter according to the present disclosure are not limited to these embodiments.

The present disclosure provides a peel-off sheet comprising a first substrate and a peel-off layer located on one surface side of the first substrate,
the peel-off layer comprises a first polyester and a second polyester;
The glass transition temperature of the first polyester is 80° C. or more and 120° C. or less,
The glass transition temperature of the second polyester is 40° C. or more and 70° C. or less,
The peel-off sheet has a ratio of the mass of the second polyester to the mass of the first polyester of 1/20 or more and 4/5 or less.

In one embodiment, the content of the first polyester may be 45% by mass or more and 95% by mass or less based on the total solid content in the peel-off layer.

In one embodiment, the number average molecular weight of the second polyester may be 5,000 or more.

In one embodiment, the thickness of the first substrate may be 1 μm or more and 5.5 μm or less.

In one embodiment, the peel-off sheet comprises a primer layer between the first substrate and the peel-off layer,
The primer layer may be adjacent to the first substrate and the peel-off layer.

In one embodiment, the peel-off layer may include particles.

In one embodiment, the average particle size of the particles may be 0.5 μm or more and 5 μm or less.

In one embodiment, the particle content may be 1% by mass or more and 10% by mass or less based on the total solid content in the peel-off layer.

The present disclosure provides a combination of a peel-off sheet and an intermediate transfer medium, comprising:
The peel-off sheet is a peel-off sheet according to the present disclosure,
The intermediate transfer medium is a combination of a peel-off sheet and an intermediate transfer medium, comprising a second substrate and a transfer layer located on one side of the second substrate, the transfer layer comprising a receiving layer, the receiving layer being the outermost layer of the intermediate transfer medium.

The present disclosure relates to
Providing a peel-off sheet and intermediate transfer medium combination according to the present disclosure;
a step of bonding the receiving layer and the peel-off layer by heating and pressing in at least a part of the removal area of the intermediate transfer medium, and then peeling off the transfer layer provided in the removal area from the intermediate transfer medium;
and transferring the transfer layer in the non-removal area from the intermediate transfer medium onto a recipient.

The present disclosure will now be described in more detail with reference to examples, but the present disclosure is not limited to these examples. Below, for materials for which the solid content ratio is written, the content before conversion to solid content is shown.

The polyesters used in the examples and comparative examples are shown in Table 1. The particles used in the examples and comparative examples are shown in Table 2.

[Example 1]
As a first substrate, a polyethylene terephthalate (PET) film (Lumirror (registered trademark), manufactured by Toray Industries, Inc.) having a thickness of 4.5 m was prepared.
A primer layer coating liquid having the following composition was applied onto one surface of the first substrate, and then dried to form a primer layer having a thickness of 0.3 μm.
Next, a coating liquid for a peel-off layer having the following composition was applied onto the primer layer and dried to form a peel-off layer having a thickness of 1 μm.
Next, a coating liquid for a back layer having the following composition was applied onto the other surface of the first substrate and dried to form a back layer having a thickness of 0.8 μm, and a peel-off sheet was obtained.

<Coating solution for primer layer>
Polyester D 10 parts by weight Methyl ethyl ketone (MEK) 25 parts by weight Toluene 25 parts by weight

<Coating solution for peel-off layer>
Polyester A 27.075 parts by weight Polyester D 1.425 parts by weight Particle A 1.5 parts by weight MEK 35 parts by weight Toluene 35 parts by weight

<Coating solution for back layer>
Polyvinyl butyral: 2 parts by weight (S-LEC (registered trademark) BX-1, manufactured by Sekisui Chemical Co., Ltd.)
Polyisocyanate 9.2 parts by mass (DIC Corporation, Burnock (registered trademark) D750)
Phosphate ester surfactant: 1.3 parts by mass (Plysurf (registered trademark) A208N, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
Talc: 0.3 parts by mass (Microace (registered trademark) P-3, manufactured by Nippon Talc Kogyo Co., Ltd.)
MEK 43.6 parts by weight Toluene 43.6 parts by weight

[Examples 2 to 10, Comparative Examples 1 to 4]
A peel-off sheet was produced in the same manner as in Example 1, except that the composition of the peel-off layer was changed as shown in Table 3. Since the peel-off layer of Comparative Example 2 did not contain the first polyester, " _W2 / _W1 " in Table 3 is shown as "-".

[Preparation of intermediate transfer medium]
As a second substrate, a PET film having a thickness of 12 μm was prepared.
Next, a coating liquid for a release layer of the intermediate transfer medium having the following composition was applied onto one surface of the second substrate, and dried to form a release layer of the intermediate transfer medium having a thickness of 1.6 μm.
Next, a coating liquid for a protective layer of the intermediate transfer medium having the following composition was applied onto the InTM release layer and dried to form a protective layer of the intermediate transfer medium having a thickness of 4.7 μm.
Next, a coating solution for the receiving layer of the intermediate transfer medium having the following composition was applied onto the InTM protective layer and dried to form a receiving layer having a thickness of 2 μm, thereby obtaining an intermediate transfer medium. The transfer layer in the intermediate transfer medium is composed of a release layer, a protective layer, and a receiving layer.

<Coating liquid for release layer of intermediate transfer medium>
Acrylic resin: 20 parts by weight (manufactured by Mitsubishi Rayon Co., Ltd., Dianale (registered trademark) BR83)
1 part by weight of polyester (Vylon (registered trademark) 600, manufactured by Toyobo Co., Ltd.)
MEK 79 parts by weight

<Coating Liquid for Protective Layer of Intermediate Transfer Member>
20 parts by weight of polyester (Vylon (registered trademark) GK-250, manufactured by Toyobo Co., Ltd.)
MEK 80 parts by weight

<Coating solution for receiving layer of intermediate transfer medium>
Vinyl chloride-vinyl acetate copolymer: 20 parts by mass (manufactured by Nissin Chemical Industry Co., Ltd., Solvine (registered trademark) CNL)
Silicone oil 1 part by mass (Shin-Etsu Chemical Co., Ltd., X-22-3000T)
MEK 79 parts by weight

<<Evaluation of peel-off properties>>
A dye-sublimation-transfer photographic thermal transfer image was formed on the receiving layer of the intermediate transfer medium prepared above. Then, the receiving layer of the intermediate transfer medium on which the thermal transfer image was formed was placed in contact with the peel-off layer of the peel-off sheet in the Examples and Comparative Examples, and a specified area of the transfer layer was removed from the intermediate transfer medium by heating the back side of the peel-off sheet using the following printer. The removal state of the transfer layer at this time was visually confirmed, and the peel-off property was evaluated based on the following evaluation criteria. The evaluation results are shown in Table 3.

(Printer)
Thermal head: KEE-57-12GAN2-STA (manufactured by Kyocera Corporation)
Heating element average resistance: 3303 (Ω)
Print density in the main scanning direction: 300 (dpi)
Sub-scanning direction print density: 300 (dpi)
Line period: 2 (msec./line)
Printing start temperature: 35 (℃)
Pulse duty ratio: 85(%)
Printing voltage: 21 (V)
Conveyance speed: 42.3mm/sec.

(Evaluation Criteria)
A: The transfer layer corresponding to the "predetermined area" is accurately removed.
B: A small portion of the transfer layer corresponding to the "predetermined area" remains, or the transfer layer has been removed so as to extend slightly beyond the "predetermined area", but this is at a level that does not cause problems when used.
C: A portion of the transfer layer corresponding to the "predetermined area" remains, or the transfer layer has been removed so as to extend beyond the "predetermined area", but this is at a level that does not cause problems when used.
NG: The transfer layer corresponding to the "predetermined region" was not removed accurately and was defective.

<<Evaluation of breakage resistance>>
After the evaluation of the peel-off properties, the state of the peel-off sheet was visually confirmed, and the breakage resistance was evaluated based on the following evaluation criteria. The evaluation results are shown in Table 3.
(Evaluation Criteria)
OK: The peel-off sheet did not break.
NG: The peel-off sheet broke.

10: peel-off sheet, 11: first substrate, 12: peel-off layer, 13: primer layer, 20: intermediate transfer medium, 21: second substrate, 22: receiving layer, 23: transfer layer, 31: transferee

Claims (9)

A peel-off sheet comprising a first substrate, a peel-off layer located on one side of the first substrate , and a primer layer located between the first substrate and the peel-off layer ,
the peel-off layer comprises a first polyester and a second polyester;
The glass transition temperature of the first polyester is 80° C. or more and 120° C. or less,
The second polyester has a glass transition temperature of 40° C. or more and 70° C. or less,
a ratio of the mass of the second polyester to the mass of the first polyester is 0.05 or more and 0.8 or less;
The primer layer is adjacent to the first substrate and the peel-off layer, forming a peel-off sheet. The peel-off sheet according to claim 1, wherein the content of the first polyester is 45% by mass or more and 95% by mass or less with respect to the total solid content in the peel-off layer. The peel-off sheet according to claim 1 or 2, wherein the number average molecular weight of the second polyester is 5,000 or more. The peel-off sheet according to any one of claims 1 to 3, wherein the thickness of the first substrate is 1 μm or more and less than 6 μm. The peel-off sheet according to any one of claims 1 to 4 , wherein the peel-off layer contains particles. The peel-off sheet according to claim 5 , wherein the particles have an average particle size of 0.5 μm or more and 5 μm or less. The peel-off sheet according to claim 5 or 6 , wherein the content of the particles is from 1% by mass to 10% by mass, based on the total amount of solids in the peel-off layer. A combination of a peel-off sheet and an intermediate transfer medium,
The peel-off sheet is the peel-off sheet according to any one of claims 1 to 7 ,
A combination of a peel-off sheet and an intermediate transfer medium, wherein the intermediate transfer medium comprises a second substrate and a transfer layer located on one side of the second substrate, the transfer layer comprising a receiving layer, and the receiving layer is the outermost layer of the intermediate transfer medium. Providing a combination of the peel-off sheet of claim 8 and an intermediate transfer medium;
a step of bonding the receiving layer and the peel-off layer by heating and pressing in at least a part of the removal area of the intermediate transfer medium, and then peeling off the transfer layer provided in the removal area from the intermediate transfer medium;
and transferring the transfer layer in a non-removal area from the intermediate transfer medium onto a receiving body.

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