JP6024513B2 - Intermediate transfer medium - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an intermediate transfer medium, and in particular, a printed matter having excellent durability and glossiness when transferring a receiving layer onto which a coloring material of a thermal transfer sheet is transferred to a transfer target. The present invention relates to an intermediate transfer medium capable of obtaining

  Conventionally, a thermal transfer method has been widely used as a simple printing method. In the thermal transfer method, a thermal transfer sheet provided with a color material layer on one surface of a base sheet and a thermal transfer image receiving sheet provided with an image receiving layer as necessary are superposed, and the thermal transfer sheet is heated by a heating means such as a thermal head. In this method, an image is formed on a thermal transfer image receiving sheet by heating the back surface of the image to an image and selectively transferring the color material contained in the color material layer.

  Thermal transfer methods are classified into a melt transfer method and a sublimation transfer method. The melt transfer method uses a thermal transfer sheet in which a heat melt ink layer in which a color material such as a pigment is dispersed in a binder such as a heat meltable wax or resin is supported on a base sheet such as a PET film, and heats a thermal head or the like. In this image forming method, energy is applied to the means in accordance with image information, and a color material is transferred together with a binder onto a thermal transfer image receiving sheet such as paper or a plastic sheet. An image obtained by the melt transfer method has a high density and excellent sharpness, and is suitable for recording binary images such as characters.

  On the other hand, the sublimation transfer method uses a thermal transfer sheet in which a dye layer in which a dye that transfers heat by sublimation is dissolved or dispersed in a resin binder is supported on a base sheet such as a PET film, and is used as a heating means such as a thermal head. This is an image forming method in which energy corresponding to image information is applied and a dye alone is transferred and transferred onto a base sheet such as paper or plastic (on a thermal transfer image receiving sheet provided with a dye receiving layer as required). . In the sublimation transfer method, the amount of dye transfer can be controlled in accordance with the amount of energy applied, so that it is possible to form a gradation image in which the image density is controlled for each dot of the thermal head. Further, since the color material to be used is a dye, the formed image is transparent, and the reproducibility of intermediate colors when dyes of different colors are superimposed is excellent. Therefore, when using thermal transfer sheets of different colors such as yellow, magenta, cyan, black, etc., and transferring each color dye on the thermal transfer image receiving sheet, high-quality photographic tone full-color images with excellent reproducibility of intermediate colors can be obtained. Formation is possible.

  Due to the development of various hardware and software related to multimedia, this thermal transfer method is a full-color hard copy system for analog images such as digital graphics and video such as still images by computer graphics, satellite communications and CD-ROM. As the market is expanding. The specific application of the thermal transfer image receiving sheet by this thermal transfer method is diverse. Typical examples include printing proofs, image output, CAD / CAM design and design output, various medical analytical instruments such as CT scans and endoscopic cameras, measuring instrument output applications and instant As an alternative to photos, output of ID cards, ID cards, credit cards, other face photos on cards, etc., as well as composite photos and amusement photos at amusement facilities such as amusement parks, game centers, museums, and aquariums Etc.

  With the diversification of uses of the above-mentioned thermal transfer image receiving sheet, there is an increasing demand for forming a thermal transfer image on an arbitrary object. Normally, a dedicated thermal transfer image-receiving sheet provided with a receiving layer on a substrate is used as an object for forming a thermal transfer image. However, in this case, the substrate and the like are restricted. Under such circumstances, as shown in Patent Document 1, an intermediate transfer medium in which a receiving layer is provided on a substrate in a detachable manner has been proposed. According to this intermediate transfer medium, using a thermal transfer sheet having a dye layer, the dye is transferred to the receptor layer to form an image, and then the intermediate transfer medium is heated to place the receptor layer on an arbitrary transfer target. Therefore, it is possible to form a thermal transfer image without being restricted by the transfer target.

  By the way, the thermal transfer image formed using the above intermediate transfer medium has a weak point lacking in durability such as weather resistance, friction resistance, chemical resistance and the like because the receiving layer on which the image is formed is located on the outermost surface. is there. Therefore, recently, as shown in Patent Document 2, an intermediate transfer medium in which a release layer, a protective layer, and a receiving layer / adhesive layer are provided on a substrate has been proposed. According to this intermediate transfer medium, since a protective layer is formed on the surface of the thermal transfer image, durability can be imparted to the thermal transfer image.

JP-A-62-238791 JP 2004-351656 A

  However, the durability of the protective layer of the intermediate transfer medium proposed in Patent Document 2 has come to satisfy the requirements of fields that require extremely high durability, such as identification cards, ID cards, and credit cards. Not in. Therefore, in order to satisfy the requirements in such a field, a durability (PET) film, usually called a pet patch, is applied on the formed image to satisfy the durability requirement. However, this method requires a separate printer and is not preferable in terms of the process.

  As a function required for the protective layer, there is a foil cutting property as well as the above durability. However, durability and foil breakability are in a trade-off relationship, and when the durability of the protective layer is to be improved, the foil breakability of the protective layer is lowered. From this, it is the present condition that both durability and foil tearability cannot be satisfied with one protective layer.

  The present invention has been made in view of such circumstances, and has a very good foil cutting property when transferring a receiving layer onto which a color material of a thermal transfer sheet has been transferred to a transfer target, and has durability and glossiness. It is a main object to provide an intermediate transfer medium that can easily obtain a printed matter excellent in the quality.

The present invention for solving the above problems is an intermediate transfer medium in which a protective layer and a receiving layer are laminated on one surface of a substrate, and the protective layer comprises two or more binder resins and a filler. And the storage elastic modulus G ′ at 70 ° C. to 90 ° C. of the mixed binder resin obtained by mixing the two or more binder resins is 1.0 × 10 ⁵ Pa to 1.0 × 10 ⁹ Pa. The storage elastic modulus G ′ at 35 ° C. exceeds 1.0 × 10 ⁹ Pa, and the mixed binder resin has a number average molecular weight (Mn) of 8000 to 30000 and a glass transition temperature (Tg). A binder resin having a temperature of 35 ° C. or more and 60 ° C. or less is included, and the filler has a particle size of 1 nm or more and 200 nm or less.

  The filler may be contained in the range of 1% by mass to 35% by mass with respect to the total solid content of the protective layer.

  Further, the binder resin having a number average molecular weight (Mn) of 8000 to 30000 and a glass transition temperature (Tg) of 35 ° C. to 60 ° C. is contained in an amount of 10% by mass or more based on the total solid content of the mixed binder resin. It may be.

  According to the intermediate transfer medium of the present invention, it is possible to easily print a printed material having excellent durability and glossiness when transferring a receiving layer onto which a coloring material of a thermal transfer sheet is transferred to a transfer target. Can get to.

It is a schematic sectional drawing which shows the layer structure of the intermediate transfer medium of this invention.

  Hereinafter, the intermediate transfer medium 10 of the present invention will be specifically described with reference to the drawings. As shown in FIG. 1, the intermediate transfer medium 10 of the present invention includes a base material 1 and a protective layer provided on one surface of the base material 1 (the upper surface of the base material 1 in the case shown in FIG. 1). 4 and the receiving layer 5. The protective layer 4 and the receiving layer 5 are layers that are transferred to a transfer medium during thermal transfer. Hereinafter, in the present invention, layers transferred to a transfer medium during thermal transfer may be collectively referred to as transfer layer 2. In the form shown in FIG. 1, the release layer 3, the plasticizer-resistant layer 6, the protective layer 4, and the receiving layer 5 constitute the transfer layer 2. The release layer 3 and the plasticizer-resistant layer 6 are arbitrary structures in the intermediate transfer medium 10 of the present invention. Hereafter, each structure of this invention is demonstrated more concretely.

(Base material)
The substrate 1 is an essential component in the intermediate transfer medium 10 of the present invention, and is provided to hold the protective layer 4 or the release layer 3 provided as necessary. The substrate 1 is not particularly limited, and examples thereof include stretched or unstretched films of plastics such as polyethylene terephthalate and polyethylene naphthalate, which have high heat resistance, polypropylene, polycarbonate, cellulose acetate, polyethylene derivatives, polyamide, polymethylpentene, and the like. . Moreover, the composite film which laminated | stacked 2 or more types of these materials can also be used. The thickness of the substrate 1 can be appropriately selected depending on the material so that its strength, heat resistance, etc. are appropriate, but usually a thickness of about 1 μm to 100 μm is preferably used.

(Transfer layer)
As shown in FIG. 1, a transfer layer 2 is formed on a substrate 1 so as to be peelable from the substrate 1 during thermal transfer. The transfer layer 2 includes at least the protective layer 4 and the receiving layer 5 that are essential components of the intermediate transfer medium 10 of the present invention, and is a layer that is peeled off from the substrate 1 and transferred to a transfer medium during thermal transfer.

(Protective layer)
The protective layer 4 contains two or more binder resins and fillers as essential components. Hereinafter, the binder resin and filler contained in the protective layer 4 will be specifically described.

<Binder resin>
The foil breakability of the protective layer 4 is considered to be greatly influenced by the glass transition temperature (Tg) of the binder resin contained in the protective layer 4, and the glass transition temperature (Tg) regardless of the number average molecular weight (Mn). When the binder resin having a temperature exceeding 60 ° C. is used, the foil cutting property is lowered. On the other hand, when the glass transition temperature (Tg) is less than 35 ° C., the foil breakability is good, but softening at normal temperature causes stickiness and the like, and the durability and storage stability of the protective layer 4 are lowered.

  On the other hand, the durability of the protective layer 4 is considered to be greatly influenced by the molecular weight of the binder resin contained in the protective layer 4, and when the number average molecular weight (Mn) of the binder resin is less than 8000, glass Durability cannot be satisfied regardless of the transition temperature (Tg). If the number average molecular weight (Mn) is 8000 or more, the durability can be satisfied, but if the number average molecular weight (Mn) exceeds 30000, the glass transition temperature (Tg) is 35 ° C. or more and 60 ° C. Even within the following range, the foil breakability is lowered.

  Therefore, in the present invention, the protective layer 4 has a number average molecular weight (Mn) of 8000 to 30,000 and a glass transition temperature (Tg) as at least one binder resin of two or more binder resins. Contains a binder resin of 35 ° C. or more and 60 ° C. or less. Hereinafter, a binder resin having a number average molecular weight (Mn) of 8000 to 30000 and a glass transition temperature (Tg) of 35 ° C. to 60 ° C. may be referred to as a “specific binder resin”.

  By including the above-mentioned “specific binder resin” in the protective layer 4, both the foil cutting property and the durability can be satisfied. In addition, in this-application specification, a number average molecular weight (Mn) means the number average molecular weight by polystyrene conversion measured by GPC. Moreover, in this specification, a glass transition temperature (Tg) means the temperature calculated | required based on the measurement (DSC method) of the calorie | heat amount change by DSC (differential scanning calorimetry).

  The number average molecular weight (Mn) of the “specific binder resin” may be within the above range, but in applications where further improvement in durability is required, the number average molecular weight (Mn) of the “specific binder resin” is It is preferable that it is 12000 or more.

  In the present invention, as will be described later, two or more kinds of binder resins including a “specific binder resin” are contained in the protective layer 4 and the storage elasticity of the “mixed binder resin” containing two or more kinds of binder resins. By adjusting the rate G ′ within a predetermined range, the protective layer 4 can be provided with extremely excellent foil cutting properties and durability. However, even when the storage elastic modulus G ′ of the “mixed binder resin” is within a predetermined range described later, the “mixed binder resin” does not include the “specific binder resin”. Compared with the protective layer 4 in the invention, the foil breakability and durability tend to be lowered.

  There is no particular limitation on the resin component constituting the “specific binder resin”, and the number average molecular weight (Mn) is 8000 or more and 30000 or less, and the glass transition temperature (Tg) is 35 ° C. or more and 60 ° C. or less. The resin component can be appropriately selected and used. For example, a polyester resin, a polyester urethane resin, a polycarbonate resin, an acrylic resin, an ultraviolet ray absorbing resin, an epoxy resin, an acrylic urethane resin, each of which has a number average molecular weight (Mn) and a glass transition temperature (Tg) satisfying the above conditions. Examples thereof include resins modified with silicone, mixtures of these resins, ionizing radiation-curable resins, ultraviolet-absorbing resins, and the like.

  Among them, in the present invention, a polyester resin and a polyester urethane resin whose number average molecular weight (Mn) and glass transition temperature (Tg) satisfy the above conditions can be suitably used as the “specific binder resin”. The polyester resin or polyester urethane resin may be a copolymer with another thermoplastic resin. Commercially available polyester resins and polyester urethane resins whose number average molecular weight (Mn) and glass transition temperature (Tg) satisfy the above conditions can be used as they are. For example, Toyobo's polyester, Byron 600 (number average) 16000, glass transition temperature (Tg); 47 ° C.), Byron GK-110 (number average molecular weight; 16000, glass transition temperature (Tg); 52 ° C.), Byron GK-780 (number average molecular weight; 11000, glass transition) Temperature (Tg); 36 ° C., unit urethane UR-1350 (number average molecular weight; 30000, glass transition temperature (Tg); 46 ° C.), and the like.

  An ionizing radiation curable resin satisfying the above conditions in terms of number average molecular weight (Mn) and glass transition temperature (Tg) is suitable as the binder resin of the present invention because of its excellent plasticizer resistance and scratch resistance. The ionizing radiation curable resin is not particularly limited, and can be appropriately selected and used from conventionally known ionizing radiation curable resins. For example, a radical polymerizable polymer or oligomer is crosslinked by irradiation with ionizing radiation, It can be hardened, added with a photopolymerization initiator as necessary, and polymerized and cross-linked with an electron beam or ultraviolet rays. The UV-absorbing resin satisfying the above conditions for the number average molecular weight (Mn) and the glass transition temperature (Tg) is suitable as a resin component of the “specific binder resin” because it is excellent in imparting light resistance to the printed matter. is there.

  As the ultraviolet absorbing resin, for example, a resin obtained by reacting and bonding a reactive ultraviolet absorbent to a thermoplastic resin or the above ionizing radiation curable resin can be used. More specifically, addition-polymerizable double-reactive organic UV absorbers such as salicylates, benzophenones, benzotriazoles, substituted acrylonitriles, nickel chelates, hindered amines, etc. Examples thereof include a bond (for example, a vinyl group, an acryloyl group, a methacryloyl group, etc.), an alcoholic hydroxyl group, an amino group, a carboxyl group, an epoxy group, and a reactive group such as an isocyanate group.

  In the present invention, the protective layer 4 contains two or more binders including the above-mentioned “specific binder resin”, and a binder resin obtained by mixing the two or more binder resins (hereinafter, two or more binder resins). The binder resin formed by mixing the binder resin is sometimes referred to as “mixed binder resin”.) The storage elastic modulus G ′ of the binder resin satisfies the following conditions 1 and 2. According to the present invention satisfying this feature, only the “specific binder resin” can be obtained by a synergistic effect between the “specific binder resin” and the “mixed binder resin” having a storage elastic modulus G ′ satisfying the following conditions 1 and 2. Compared with the containing protective layer, the foil breakability and durability can be further improved.

Condition 1: The storage elastic modulus G ′ of the “mixed binder resin” at 70 ° C. to 90 ° C. is 1.0 × 10 ⁵ Pa to 1.0 × 10 ⁹ Pa.
Condition 2: The storage elastic modulus G ′ of the “mixed binder resin” at 35 ° C. exceeds 1.0 × 10 ⁹ Pa.

Condition 1 is the storage elastic modulus G ′ focusing on the temperature at which the transfer layer 2 including the protective layer 4 is peeled from the substrate 1, and the storage elastic modulus G of the “mixed binder resin” at 70 ° C. to 90 ° C. By setting 'to 1.0 × 10 ⁵ Pa or more and 1.0 × 10 ⁹ Pa or less, durability and foil breakage are improved.

Condition 2 is a storage elastic modulus G ′ that focuses on durability and storage stability, and the transfer elastic modulus G ′ at 35 ° C. is “mixed binder resin” exceeding 1.0 × 10 ⁹ Pa. There is no stickiness on the surface of the printed material to which the layer 2 has been transferred, and the durability and storage stability of the protective layer 4 can be improved. Further, by using a “mixed binder resin” that satisfies the condition 2, the protective layer 4 can be used even when the temperature of the printed material to which the transfer layer 2 has been transferred increases from around room temperature to around 35 ° C. The durability and storage stability can be fully satisfied.

  In the present invention, the storage elastic modulus G ′ of the “mixed binder resin” obtained by mixing two or more binder resins including the “specific binder resin” is adjusted to satisfy the above conditions 1 and 2, This is because it is currently difficult to satisfy the above conditions 1 and 2 for the storage elastic modulus G ′ using only the “specific binder resin”. That is, the binder resin other than the “specific binder resin” contained in the protective layer 4 plays a role for adjusting the storage elastic modulus G ′ so as to satisfy the above conditions 1 and 2. Further, as a binder resin that plays a role in adjusting the storage elastic modulus G ′ so as to satisfy the above conditions 1 and 2, those having a relatively high glass transition temperature (Tg), specifically, a glass transition temperature (Tg). When a resin having a temperature of 65 ° C. or higher is used, it is possible to further improve storage stability and durability. On the other hand, when a resin having a relatively low glass transition temperature (Tg), specifically, a glass transition temperature (Tg) of 10 ° C. or more and less than 35 ° C. is used, the protective layer is maintained while maintaining its preservability. Transferability can be further improved. Therefore, when adjusting the storage elastic modulus G ′ of the “mixed binder resin” with a binder resin other than the “specific binder resin”, a binder resin other than the “specific binder resin” is appropriately selected in consideration of these points. It is preferable to set.

  Examples of the binder resin for adjusting the storage elastic modulus G ′ so as to satisfy the above conditions 1 and 2 include, for example, a polyester resin, a polycarbonate resin, an acrylic resin, an ultraviolet absorbing resin, an epoxy resin, a polystyrene resin, and a polyester urethane resin. An acrylic urethane resin, a resin obtained by modifying each of these resins with silicone, a mixture of these resins, an ionizing radiation curable resin, an ultraviolet absorbing resin, or the like can be used. Among them, in the present invention, the storage elastic modulus G ′ satisfies the above conditions 1 and 2 and is a polyester resin, a polyester urethane resin, a copolymer of these resins and other thermoplastic resins, or a storage elastic modulus G ′. The resin to be adjusted within the above range preferably contains a polyester resin, a polyester urethane resin, and a copolymer of these resins and other thermoplastic resins. Polyester resins, polyester urethane resins, or copolymers of these resins and other thermoplastic resins can be easily adjusted for storage elastic modulus G ′, and can be expected to further improve foil breakability and durability. it can.

  If the storage elastic modulus G ′ of the “mixed binder resin” finally satisfies the above conditions 1 and 2, the storage elastic modulus G ′ of each binder resin contained in the protective layer 4 is particularly good. There is no limitation, and each binder resin itself does not need to satisfy the above conditions 1 and 2. In addition, the two or more binder resins included in the “mixed binder resin” may both be “specific binder resins”. That is, the storage elastic modulus G ′ is adjusted to satisfy the above conditions 1 and 2 by using a mixture of two or more “specific binder resins” without using any binder resin other than the “specific binder resin”. May be. In addition, two or more “specific binder resins” can be used in combination with one or two or more “specific binder resins”. Also, one type of “specific binder resin” and two or more types of binder resins other than “specific binder resin” may be used in combination.

  The ionizing radiation curable resin is suitable as a binder resin for adjusting the storage elastic modulus G ′ within the above range from the viewpoint of excellent plasticizer resistance and scratch resistance. The ionizing radiation curable resin is not particularly limited, and can be appropriately selected and used from conventionally known ionizing radiation curable resins. For example, a radical polymerizable polymer or oligomer is crosslinked by irradiation with ionizing radiation, It can be hardened, added with a photopolymerization initiator as necessary, and polymerized and cross-linked with an electron beam or ultraviolet rays. The ultraviolet absorbing resin for adjusting the storage elastic modulus G ′ within the above range is suitable as a binder resin in that it is excellent in imparting light resistance to a printed matter.

  The storage elastic modulus G ′ of the “mixed binder resin” is a value measured by a dynamic viscoelasticity measuring device in accordance with JIS K7244-6. As the dynamic viscoelasticity measuring device, an ARES dynamic viscoelasticity measuring device (Advanced Rheometric Expansion System) manufactured by TA Instruments Japan can be used.

  In the present specification, the storage elastic modulus G ′ of “mixed binder resin” is a numerical value calculated by measuring the storage elastic modulus G ′ of each resin and calculating the ratio thereof. Hereinafter, a binder resin in which two or more kinds of resins are mixed is resin A (a%), resin B (b%), resin C (c%), three kinds of resins (a% + b% + c% = 100%) The storage elastic modulus G ′ of “mixed binder resin” in which two or more kinds of resins are mixed will be described by taking as an example the case of forming from the above. The following formula is used to calculate the storage elastic modulus G ′ of the “mixed binder resin”. G ′ (A) in the formula is the storage elastic modulus G ′ of the resin A, G ′ (B) is the storage elastic modulus G ′ of the resin B, and G ′ (C) is the storage elastic modulus of the resin C. G 'means. G ′ means the storage elastic modulus G ′ of the “mixed binder resin”.

  The content of the “mixed binder resin” is not particularly limited, but when the content of the “mixed binder resin” is less than 65% by mass with respect to the total solid content of the protective layer 4, the foil breakability and durability Tend to decrease. Moreover, since content of the filler mentioned later will fall when it exceeds 99 mass%, it exists in the tendency for the improvement effect of the foil cutting property by containing of a filler to fall. Therefore, in consideration of this point, the “mixed binder resin” is preferably contained in the range of 65% by mass to 99% by mass with respect to the total solid content of the protective layer 4.

  There is no particular limitation on the content of the “specific binder resin” with respect to the total solid content of the “mixed binder resin”, and only the “specific binder resin” exists in the “mixed binder resin”. As compared with the “mixed binder resin” that does not contain, the foil breakability and durability can be improved. When the content of the “specific binder resin” relative to the total solid content of the “mixed binder resin” is less than 10% by mass, the effect of improving foil breakage and durability by the “specific binder resin” is reduced. Tend to. Therefore, the content of the “specific binder resin” is preferably 10% by mass or more with respect to the total solid content of the “mixed binder resin”. The upper limit is not particularly limited as long as the storage elastic modulus G ′ is contained in a range in which the above conditions 1 and 2 can be satisfied. For example, as described above, when adjusting the storage elastic modulus G ′ by using a mixture of two or more “specific binder resins” without using a binder resin other than the “specific binder resin”. The content of the “specific binder resin” with respect to the total solid content of the “mixed binder resin” is 100% by mass. That is, the upper limit is 100% by mass. In addition, when the binder resin other than the “specific binder resin” is included in the “mixed binder resin”, in other words, when the storage elastic modulus G ′ is adjusted using a binder resin other than the “mixed binder resin” As an example of the upper limit of the content of the “specific binder resin”, it is about 80% by mass.

<Filler>
In the above, the protective layer 4 includes the “mixed binder resin” having the storage elastic modulus G ′ satisfying the above conditions 1 and 2 and including the “specific binder resin”, so Although the description has focused on the point where the durability is improved, in the present invention, the foil breakability is further improved by the approach from the filler side. Specifically, the protective layer 4 contains a filler having a particle size of 1 nm to 200 nm. According to the protective layer 4 containing a filler having a particle diameter of 1 nm or more and 200 nm or less, the foil breakability when transferring the protective layer without reducing the glossiness of the protective layer 4, The durability of the transferred image can be improved.

  Including the “specific binder resin”, and the “mixed binder resin” that satisfies the above conditions 1 and 2, together with the filler having a particle size in the above range, the protective layer 4 can be used to produce the above-described excellent effects. Although the mechanism is not necessarily clear at present, the shearing property of the protective layer 4 is improved by incorporating a filler having a particle size in the above-mentioned range into the protective layer 4, and the improvement of the shearing property improves the foil cutting property. It is presumed that they act on Further, since the filler contained in the protective layer 4 has a very small particle size of 1 nm or more and 200 nm or less, the “specific binder resin” or the storage elastic modulus G ′ can be used without causing a decrease in gloss. It is inferred that the foil breakability and durability exhibited by the “mixed binder resin” with a specified value within a predetermined range can be further improved.

  The particle size of the filler in the present invention means a volume average particle size. The particle size of the filler can be measured, for example, by analyzing a BET method or an electron microscope observation result using image analysis type particle size distribution measurement software.

  The filler only needs to satisfy the condition that the particle size is 1 nm or more and 200 nm or less, and any of organic fillers, inorganic fillers, and organic-inorganic hybrid fillers can be used preferably. These fillers may be powder or sol-based. Examples of the organic filler in powder include acrylic particles such as non-crosslinked acrylic particles and crosslinked acrylic particles, polyamide particles, fluorine particles, and polyethylene wax. Examples of the powdery inorganic filler include metal oxide particles such as calcium carbonate particles, silica particles, and titanium oxide. Examples of the organic-inorganic hybrid filler include those obtained by hybridizing silica particles to an acrylic resin. Examples of the sol-based filler include silica sol-based and organosol-based fillers. These fillers may be used alone or in combination of two or more. Moreover, if a particle size is in the said range, you may contain the filler from which a particle size differs. The present invention is characterized in that the protective layer 4 contains a filler having a particle size within the above range, but excludes that a part of the filler outside this range is contained. Instead, as long as the gist of the present invention is not disturbed, a part of the filler having a particle size outside the above range may be contained.

  As described above, if the filler contained in the protective layer 4 is in the range of the particle diameter under the above conditions, the foil breakability and durability are improved even when any filler is used. However, it is preferable to use an organic filler for the purpose of further improving the durability. As the organic filler, acrylic particles are particularly suitable. This is considered to be related to the good compatibility of the organic filler. Specifically, the organic filler is more compatible than the inorganic filler. Therefore, when the protective layer 4 is formed using an organic filler, it is considered that the adhesion of the protective layer 4 is improved as compared with the case where an inorganic filler is used, and the durability is further improved by improving the adhesion. Is expected.

  The filler may be a powder or a sol-based filler, but the powder filler has a wide solvent selectivity when preparing a coating liquid for forming the protective layer 4. And it is preferable in that it is excellent in coating suitability.

  The filler content is not particularly limited, but when the filler content is less than 1% by mass relative to the total solid content of the protective layer 4, the foil breakability may not be sufficiently satisfied. On the other hand, when it exceeds 35% by mass, the transparency and durability of the protective layer 4 tend to decrease. Therefore, considering this point, it is preferable that the filler is contained in the range of 1% by mass to 35% by mass with respect to the total solid content of the protective layer 4.

  The protective layer 4 of the present invention includes a “mixed binder resin” including a “specific binder resin” having a storage elastic modulus G ′ adjusted within the above range, a fluorescent whitening agent together with a filler having a particle size within the above range, You may contain other materials, such as UV absorber for improving weather resistance.

  In the present invention, since the foil breakability of the protective layer 4 is good, the thickness of the protective layer 4 can be made larger than the thickness of the conventional protective layer, including the “specific binder resin” and the storage elastic modulus G ′. In addition to the durability exhibited by the “mixed binder resin” satisfying the above conditions 1 and 2, and the filler having a particle size in the above range, an improvement in durability by increasing the thickness can be expected. Even when the thickness of the protective layer 4 is reduced, the “mixed binder resin” containing the “specific binder resin” and having the storage elastic modulus G ′ satisfying the above conditions 1 and 2 and the particle size of the protective layer 4 are as described above. The durability of the protective layer 4 can be satisfied by the filler in the range. Although there is no limitation in particular about the thickness of the protective layer 4, when the thickness of the protective layer 4 exceeds 30 micrometers, there exists a tendency for foil cutting property to fall, and when it is less than 2 micrometers, durability falls. There is a tendency. Therefore, considering this point, the thickness of the protective layer 4 is preferably 2 μm or more and 30 μm or less.

  As a method of forming the protective layer 4, the storage modulus G ′ of the “mixed binder resin” including the “specific binder resin” and the “specific binder resin” satisfies the above conditions 1 and 2 “ `` Specific binder resin '', binder resin for adjusting storage elastic modulus G ′, filler having a particle size in the above range, and various materials added as necessary are dissolved or dispersed in an appropriate solvent. A protective layer coating solution is prepared, and this is applied to the substrate 1 (release layer 3 provided on the substrate 1 as necessary) using a gravure printing method, a screen printing method or a reverse coating method using a gravure plate It can be formed by coating and drying by a conventionally known means such as.

(Receptive layer)
As shown in FIG. 1, a receiving layer 5 constituting the transfer layer 2 is provided on the protective layer 4. On this receiving layer, an image is formed by thermal transfer from a thermal transfer sheet having a color material layer by thermal transfer. Then, the transfer layer 2 of the intermediate transfer medium on which the image is formed is transferred onto the transfer target, and as a result, a printed matter is formed. For this reason, as a material for forming the receiving layer 5, a conventionally known resin material that can easily receive a heat transferable color material such as a sublimation dye or a heat-meltable ink can be used. For example, polyolefin resin such as polypropylene, halogenated resin such as polyvinyl chloride or polyvinylidene chloride, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer or polyacrylate Vinyl resins, polyester resins such as polyethylene terephthalate or polybutylene terephthalate, polystyrene resins, polyamide resins, copolymers of olefins such as ethylene or propylene and other vinyl polymers, cellulose resins such as ionomers or cellulose diastase Polycarbonate and the like, and vinyl chloride resin, acrylic-styrene resin or polyester resin is particularly preferable.

  When the receiving layer 5 is transferred to the transfer medium via the adhesive layer, the adhesiveness of the receiving layer 5 itself is not necessarily required. However, when the receptor layer 5 is transferred to the transfer medium without passing through the adhesive layer, the receptor layer 5 may be formed using an adhesive resin material such as vinyl chloride-vinyl acetate copolymer. preferable.

The receptive layer 5 is a receptive layer coating obtained by adding one or more materials selected from the above-mentioned materials and various additives as necessary, and dissolving or dispersing them in an appropriate solvent such as water or an organic solvent. A working solution is prepared, and this can be formed by coating and drying by means of a gravure printing method, a screen printing method or a reverse coating method using a gravure plate. Its thickness is 1g / m ² ~10g / m ² approximately in a dry state.

(Peeling layer)
In order to improve the peelability of the transfer layer 2 from the substrate 1, a release layer 3 may be provided between the substrate 1 and the protective layer 4. The release layer 3 is an arbitrary layer that constitutes the transfer layer 2 and moves onto the transfer target during thermal transfer. The release layer 3 improves the peelability of the transfer layer 2 and provides the protective layer 4 and the release layer 3. This is preferable in that the durability of the printed product can be further improved by the synergistic effect.

  Examples of the material of the release layer 3 include conventionally known materials, for example, cellulose derivatives such as ethyl cellulose, nitrocellulose, and cellulose acetate, acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, and polybutyl acrylate, and polyvinyl chloride. , Thermoplastic resins of vinyl copolymers such as vinyl chloride-vinyl acetate copolymer and polyvinyl butyral, thermosetting types such as saturated or unsaturated polyester resins, polyurethane resins, thermally crosslinkable epoxy-amino resins, amino alkyd resins Resin, silicone wax, silicone resin, silicone-modified resin, fluorine resin, fluorine-modified resin, polyvinyl alcohol and the like. The release layer 3 preferably contains a filler such as microsilica or polyethylene wax in order to improve the foil breakability. Further, the release layer 3 may be made of one kind of resin, or may be made of two or more kinds of resins. The release layer 3 may be formed using a crosslinking agent such as an isocyanate compound, a catalyst such as a tin catalyst, and an aluminum catalyst in addition to the resin exemplified above.

  The release layer 3 provided as necessary is obtained by dispersing or dissolving the above resin in a solvent, and coating it on at least a part of the substrate 1 by a known coating method such as roll coating, gravure coating, bar coating or the like. -It can be formed by drying. The thickness of the release layer 3 is usually about 0.1 μm to 5 μm, preferably about 0.5 μm to 2 μm.

(Plasticizer resistant layer)
In order to improve the plasticizer resistance of the printed material to which the transfer layer 2 is transferred, the plasticizer is provided between the release layer 3 and the protective layer 4 when the substrate 1 and the protective layer 4 and the release layer 3 are provided. A conductive layer 6 may be provided.

  As the plasticizer-resistant layer 6, a material that repels the plasticizer component or a material that does not easily reach the image can be preferably used. Examples of the material that repels the plasticizer component include polyvinyl alcohol resin, polyvinyl butyral resin, polyvinyl acetal resin, polyvinyl pyrrolidone resin, and the like. Examples of the material in which the plasticizer component hardly reaches the image include cationic resins such as a cationic urethane emulsion. These materials may be used alone or in combination of two or more.

  In addition, the polyvinyl alcohol resin, polyvinyl butyral resin, and polyvinyl acetal resin exemplified as materials for repelling the plasticizer component preferably have a saponification degree of 30 to 100%, and more preferably 60 to 100%. By including a polyvinyl alcohol resin, a polyvinyl butyral resin, or a polyvinyl acetal resin having a saponification degree within this range in the plasticizer-resistant layer 6, the plasticizer resistance of the transfer layer 2 can be further improved. In addition, the saponification degree in this invention means the value which divided the number of moles of the vinyl alcohol structure in a polymer by the number of moles of all the monomers in a polymer. The material that repels the plasticizer component or the material that is difficult for the plasticizer component to reach the image is preferably contained in the range of 20% by mass to 100% by mass with respect to the total solid content of the plasticizer-resistant layer 6. .

  In addition, the plasticizer-resistant layer may include, for example, a lubricant, a plasticizer, a filler, an antistatic agent, an antiblocking agent, a crosslinking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a dye, Colorants such as pigments, fluorescent brighteners, other additives, and the like may be added.

  The plasticizer-resistant layer 6 provided as necessary is formed by dissolving or dispersing one or more of the above-exemplified materials and various materials added as necessary with an appropriate solvent. It can be formed by preparing a coating liquid for the adhesive layer and coating and drying it on the substrate 1 or the release layer 3 provided as necessary. Although there is no limitation in particular about the thickness of a plasticizer-resistant layer, Usually, it is 0.1 micrometer-50 micrometers in the thickness after drying, Preferably it is about 1 micrometer-20 micrometers.

(Transfer material)
The transfer layer 2 on which the above-described thermal transfer image of the intermediate transfer medium is formed is transferred onto the transfer target, and as a result, a printed matter having a thermal transfer image having various durability is obtained. The transfer target to which the intermediate transfer medium of the present invention is applied is not particularly limited. For example, natural fiber paper, coated paper, tracing paper, plastic film that does not deform by heat during transfer, glass, metal, ceramics, wood, cloth Any of these may be used.

(Image forming method)
The method for forming an image on the receiving layer surface using the thermal transfer image receiving sheet of the present invention is not particularly limited, and can be performed by a known thermal transfer method.

  Further, as the thermal transfer sheet used in the image formation, for example, a heat transferable color material layer is provided on one surface of a substrate such as a polyester film, and a back layer is provided on the other surface of the substrate. A conventionally known thermal transfer sheet can be used. Hereinafter, the thermal transfer sheet will be described.

(Base material)
As the base material, any material may be used as long as it has a conventionally known heat resistance and strength. For example, polyethylene terephthalate film, 1,4-polycyclohexylenedimethylene terephthalate film, polyethylene naphthalate film, polyphenylene Sulfide film, polystyrene film, polypropylene film, polysulfone film, aramid film, polycarbonate film, polyvinyl alcohol film, cellophane, cellulose derivatives such as cellulose acetate, polyethylene film, polyvinyl chloride film, nylon film, polyimide film, ionomer film, etc. Resin film; paper such as condenser paper, paraffin paper, synthetic paper; non-woven fabric; composite of paper, non-woven fabric and resin, etc.

  Although there is no limitation in particular about the thickness of a base material, it is 0.5-50 micrometers normally, Preferably it is about 1.5-10 micrometers.

  The base material may be surface-treated in order to improve the adhesiveness with an adjacent layer. As the surface treatment, known resin surface modification techniques such as corona discharge treatment, flame treatment, ozone treatment, ultraviolet treatment, radiation treatment, surface roughening treatment, chemical treatment, plasma treatment, grafting treatment, etc. can be applied. it can. Only one type of surface treatment may be performed, or two or more types may be performed. Moreover, the undercoat layer (primer layer) may be provided in the one surface or both surfaces as needed.

(Heat transferable color material layer)
The thermal transfer colorant layer is a layer containing a sublimation dye when the thermal transfer sheet is a sublimation type thermal transfer sheet, and a layer containing a thermal melt composition containing a colorant in the case of a thermal melt type thermal transfer sheet. It becomes. Also, thermal transfer in which a layer region containing a sublimable dye and a layer region containing a heat-meltable ink comprising a heat-melting composition containing a colorant are provided on a single continuous substrate in a surface sequential manner. A sheet can also be used.

  Examples of sublimation dyes include diarylmethane dyes; triarylmethane dyes; thiazole dyes; merocyanine dyes; pyrazolone dyes; methine dyes; indoaniline dyes; Azomethine dyes such as azomethine and pyridone azomethine; xanthene dyes; oxazine dyes; cyanostyrene dyes such as dicyanostyrene and tricyanostyrene; thiazine dyes; azine dyes; acridine dyes; benzeneazo dyes; Azo dyes such as azo, isothiazole azo, pyrrole azo, pyrazole azo, imidazole azo, thiadiazole azo, triazole azo, disazo; spiropyran dyes; indolinospiropyran dyes ; Fluoran dyes; rhodamine lactam dyes; naphthoquinone dyes; anthraquinone dyes; quinophthalone dyes; and the like, and more specifically, the compounds exemplified in JP-A-7-149062 and the like. In the thermal transferable color material layer, the content of the sublimable dye is 5% to 90% by mass, preferably 10% to 70% by mass, based on the total solid content of the thermal transferable color material layer. Is preferred. When the content of the sublimation dye is less than the above range, the printing density may be lowered, and when it exceeds the above range, the storage stability and the like may be deteriorated.

  Examples of the binder resin for supporting the dye include cellulose resins such as ethyl cellulose resin, hydroxyethyl cellulose resin, ethyl hydroxy cellulose resin, methyl cellulose resin, nitrocellulose resin, and cellulose acetate resin, polyvinyl alcohol resin, and polyvinyl acetate resin. , Polyvinyl butyral resin, polyvinyl acetal resin, vinyl resins such as polyvinyl pyrrolidone, acrylic resins such as poly (meth) acrylate and poly (meth) acrylamide, polyurethane resins, polyamide resins, polyester resins, phenoxy resins, phenols Examples thereof include resins and epoxy resins. Among these, cellulose-based, vinyl-based, acrylic-based, polyurethane-based, and polyester-based resins are preferable from the viewpoints of heat resistance, dye transferability, and the like.

  The heat transferable color material layer may contain a release agent, inorganic fine particles, organic fine particles and the like. Examples of the mold release agent include silicone oil, polyethylene wax, and phosphate ester. Examples of the silicone oil include straight silicone oil, modified silicone oil, and cured products thereof. The silicone oil may be reactive or non-reactive. Inorganic fine particles include carbon black, aluminum, molybdenum disulfide and the like. The modified silicone oil can be classified into a reactive silicone oil and a non-reactive silicone oil. The reactive silicone oil includes amino modification, epoxy modification, carboxyl modification, hydroxy modification, methacryl modification, mercapto modification, phenol modification, one-terminal reactivity and heterofunctional modification. Non-reactive silicone oils include polyether modification, methylstyryl modification, alkyl modification, higher fatty acid ester modification, hydrophilic special modification, higher alkoxy modification, fluorine modification and the like. The amount of silicone oil added is preferably 0.1 to 15% by mass, more preferably 0.3 to 10% by mass, based on the mass of the binder. Examples of the organic fine particles include polyethylene wax.

  The heat transferable color material layer is, for example, a coating solution for a heat transferable color material layer in which a sublimable dye, a binder resin, and various components optionally added as necessary are dispersed or dissolved in an appropriate solvent. It can be formed on a substrate by coating and drying using a conventionally known coating method. Conventionally known coating methods include a ravia printing method, a reverse roll coating method using a gravure plate, a roll coater, a bar coater and the like. Examples of the solvent include toluene, methyl ethyl ketone, ethanol, isopropyl alcohol, cyclohexanone, dimethylformamide [DMF] and the like.

  There is no limitation in particular about the thickness of a heat transferable color material layer, and it is about 0.2 micrometer-5 micrometers normally.

(Back layer)
In addition, a back layer for improving heat resistance, running performance of the thermal head during printing, and the like may be provided on the other surface of the substrate.

  The back layer can be formed by appropriately selecting a conventionally known thermoplastic resin or the like. As such a thermoplastic resin, for example, polyester resins, polyacrylate resins, polyvinyl acetate resins, styrene acrylate resins, polyurethane resins, polyethylene resins, polypropylene resins, and other polyolefin resins, Polystyrene resin, polyvinyl chloride resin, polyether resin, polyamide resin, polyimide resin, polyamideimide resin, polycarbonate resin, polyacrylamide resin, polyvinyl chloride resin, polyvinyl butyral resin, polyvinyl acetoacetal resin, etc. Examples thereof include thermoplastic resins such as polyvinyl acetal resin, and silicone modified products thereof. Among these, from the viewpoint of heat resistance, a polyamideimide resin or a modified silicone product thereof can be preferably used.

  In addition to the above thermoplastic resin, the back layer has a wax, a higher fatty acid amide, a phosphoric ester compound, a metal soap, a silicone oil, a surfactant release agent, etc., a fluororesin for the purpose of improving slip properties. It is preferable that various additives such as organic particles such as silica, clay, talc, and calcium carbonate are contained, and it is particularly preferable that at least one of phosphoric acid ester or metal soap is contained. .

  For example, the back layer is formed by applying a coating liquid obtained by dispersing or dissolving the thermoplastic resin and various additives that are added as necessary in a suitable solvent on a substrate, a gravure printing method, a screen printing method, a gravure It can be formed by coating and drying by known means such as a reverse roll coating printing method using a plate. The thickness of the back layer is preferably 2 μm or less, and more preferably about 0.1 μm to 1 μm.

  Next, the present invention will be described more specifically with reference to examples and comparative examples. Hereinafter, unless otherwise specified, parts or% is based on mass. Mn represents the number average molecular weight, and Tg represents the glass transition temperature.

Example 1
A polyethylene terephthalate film (Toray Co., Ltd., Lumirror) with a thickness of 12 μm is used as a substrate, and a coating solution for a release layer having the following composition is dried on the substrate to a thickness of 1.0 g / m ^2. Coating was performed to form a release layer. Next, the protective layer coating liquid 1 having the following composition was applied on the release layer so as to have a thickness of 10.0 g / m ^{2 in} a dry state to form a protective layer. Further, the receiving layer coating liquid having the following composition was coated on the protective layer so as to have a thickness of 2.0 g / m ^{2 in} a dry state to form a receiving layer, whereby the intermediate transfer medium of Example 1 was obtained. Obtained. The release layer coating solution, the protective layer coating solution 1, and the receiving layer coating solution were all applied by gravure coating. The storage elastic modulus G ′ of the binder resin has the value shown in Table 1, and the storage elastic modulus G ′ is a value calculated using the following measuring device. The storage elastic modulus G ′ of the “mixed binder resin” obtained by mixing the binder resins contained in the protective layer coating liquid is used to calculate the storage elastic modulus G ′ of the “mixed binder resin”. This is a calculated value calculated based on the above formula.

Storage elastic modulus measuring device; ARES dynamic viscoelasticity measuring device (Advanced Rheometric Expansion System) manufactured by TA Instruments Japan
Measurement conditions: Parallel plate 10 mmΦ, strain 1%, amplitude (frequency) 1 Hz, temperature increase rate 2 ° C./min, measurement temperature 30 ° C. to 200 ° C.

<Coating liquid for release layer>
・ 95 parts acrylic resin (BR-87, Mitsubishi Rayon Co., Ltd.)
・ Polyester resin 5 parts (Byron 200, Toyobo Co., Ltd.)
・ Toluene 200 parts ・ MEK 200 parts

<Protective layer coating solution 1>
Binder resin (mass ratio (A) / (B) = 3/7) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
Filler (acrylic particles) 2.22 parts (MP300 particle size 100 nm Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

<Coating liquid for receiving layer>
・ 95 parts of vinyl chloride-vinyl acetate copolymer (CNL, Nissin Chemical Industry Co., Ltd.)
・ Epoxy-modified silicone oil 5 parts (KP-1800U, Shin-Etsu Chemical Co., Ltd.)
・ Toluene 200 parts ・ MEK 200 parts

(Example 2)
The protective layer coating solution 1 was changed to a protective layer coating solution 2 having the following composition, and the protective layer coating solution 2 was applied to a thickness of 5.0 g / m ^{2 in} a dry state. In the same manner as in Example 1, an intermediate transfer medium of Example 2 was obtained.

<Protective layer coating solution 2>
Binder resin (mass ratio (A) / (B) = 3/7) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
・ Filler (acrylic particles) 1.05 parts (MP300 particle size 100 nm Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Example 3)
An intermediate transfer medium of Example 3 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 3 having the following composition.

<Coating liquid 3 for protective layer>
Binder resin (mass ratio (A) / (B) = 7/3) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
・ Filler (acrylic particles) 5 parts (MP300, particle size 100 nm, Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

Example 4
An intermediate transfer medium of Example 4 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 4 having the following composition.

<Coating liquid 4 for protective layer>
Binder resin (mass ratio (A) / (B) = 7/3) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
・ Filler (silica) 5 parts (633238 particle size: 10 nm to 20 nm, SIGMA-ALDRICH)
・ Toluene 40 parts ・ MEK 40 parts

(Example 5)
An intermediate transfer medium of Example 5 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 5 having the following composition.

<Coating liquid 5 for protective layer>
Binder resin (mass ratio (A) / (B) = 7/3) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
-Filler (acrylic particles) 8.57 parts (MP300 particle size 100 nm, Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Example 6)
An intermediate transfer medium of Example 6 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 6 having the following composition.

<Coating liquid 6 for protective layer>
Binder resin (mass ratio (A) / (B) = 85/15) 20 parts (A) Polyester resin (Mn; 23000, Tg; 67 ° C.)
(Byron 270, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
Filler (acrylic particles) 2.22 parts (MP300 particle size 100 nm Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Example 7)
An intermediate transfer medium of Example 7 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 7 having the following composition.

<Coating liquid 7 for protective layer>
Binder resin (mass ratio (A) / (B) = 5/5) 20 parts (A) Polyester resin (Mn; 17000, Tg; 67 ° C.)
(Byron 200, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 10,000, Tg; 60 ° C.)
(GK250, Toyobo Co., Ltd.)
Filler (acrylic particles) 3.53 parts (MP300 particle size 100 nm Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Example 8)
An intermediate transfer medium of Example 8 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 8 having the following composition.

<Protective layer coating solution 8>
Binder resin (mass ratio (A) / (B) = 6/4) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK-880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 23000, Tg; 47 ° C.)
(Byron 103, Toyobo Co., Ltd.)
-Filler (acrylic particles) 8.57 parts (MP300 particle size 100 nm, Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

Example 9
An intermediate transfer medium of Example 9 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 9 having the following composition.

<Coating liquid 9 for protective layer>
Binder resin (mass ratio (A) / (B) / (C) = 2/2/1) 20 parts (A) Polyester resin (Mn; 17000, Tg; 67 ° C.)
(Byron 200, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
(C) Polycarbonate resin (FPC-2136, Mitsubishi Gas Chemical Co., Inc.)
Filler (acrylic particles) 3.53 parts (MP300 particle size 100 nm Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Example 10)
An intermediate transfer medium of Example 10 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution 10 having the following composition.

<Protective layer coating solution 10>
Binder resin (mass ratio (A) / (B) = 5/5) 20 parts (A) Polyester resin (Mn; 23000, Tg; 47 ° C.)
(Byron 103, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 10,000, Tg; 60 ° C.)
(GK250, Toyobo Co., Ltd.)
Filler (acrylic particles) 2.22 parts (MP300 particle size 100 nm Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 1)
An intermediate transfer medium of Comparative Example 1 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution A having the following composition.

<Coating liquid A for protective layer>
20 parts of polyester resin (Mn; 18000, Tg; 84 ° C.) (Byron GK-880, Toyobo Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 2)
An intermediate transfer medium of Comparative Example 2 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution B having the following composition.

<Coating liquid B for protective layer>
-20 parts of binder resin (polymethyl methacrylate) (Dianar BR80, Mitsubishi Rayon Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 3)
An intermediate transfer medium of Comparative Example 3 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution C having the following composition.

<Coating liquid C for protective layer>
・ 20 parts of binder resin (polycarbonate resin) (FPC-2136, Mitsubishi Gas Chemical Co., Inc.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 4)
An intermediate transfer medium of Comparative Example 4 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution D having the following composition.

<Coating liquid D for protective layer>
・ 20 parts of binder resin (polyester resin) (UE-3500, Unitika Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 5)
An intermediate transfer medium of Comparative Example 5 was obtained in the same manner as Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution E having the following composition.

<Coating liquid E for protective layer>
Binder resin (mass ratio (A) / (B) = 1/4) 20 parts (A) Polyester resin (Mn; 17000, Tg = 67 ° C.)
(Byron 200, Toyobo Co., Ltd.)
(B) Polycarbonate resin (FPC-2136, Mitsubishi Gas Chemical Co., Inc.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 6)
An intermediate transfer medium of Comparative Example 6 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution F having the following composition.

<Coating fluid F for protective layer>
Binder resin (mass ratio (A) / (B) = 9/1) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 7)
An intermediate transfer medium of Comparative Example 7 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution G having the following composition.

<Coating liquid G for protective layer>
-Binder resin (mass ratio (A) / (B) = 4/1) 20 parts (A) Polymethyl methacrylate (Dianar BR80, Mitsubishi Rayon Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 8)
An intermediate transfer medium of Comparative Example 8 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution H having the following composition.

<Coating liquid H for protective layer>
Binder resin (mass ratio (A) / (B) = 9/1) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
-Filler (acrylic particles) 8.57 parts (MP300 particle size 100 nm, Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 9)
An intermediate transfer medium of Comparative Example 9 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution I having the following composition.

<Coating liquid I for protective layer>
-Binder resin (mass ratio (A) / (B) = 4/1) 20 parts (A) Polymethyl methacrylate (Dianar BR80, Mitsubishi Rayon Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
-Filler (acrylic particles) 8.57 parts (MP300 particle size 100 nm, Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

(Comparative Example 10)
An intermediate transfer medium of Comparative Example 10 was obtained in the same manner as in Example 1 except that the protective layer coating solution 1 was changed to the protective layer coating solution J having the following composition.

<Coating liquid J for protective layer>
Binder resin (mass ratio (A) / (B) = 7/3) 20 parts (A) Polyester resin (Mn; 18000, Tg; 84 ° C.)
(Byron GK880, Toyobo Co., Ltd.)
(B) Polyester resin (Mn; 16000, Tg; 47 ° C.)
(Byron 600, Toyobo Co., Ltd.)
Filler (acrylic particles) 8.57 parts (MP-2200 particle size 350 nm, Soken Chemical Co., Ltd.)
・ Toluene 40 parts ・ MEK 40 parts

<< Durability (Taber test) >>
Using a HDP-600 printer (manufactured by HID) and a thermal transfer sheet prepared by the following method, a solid black image was formed on the receiving layer of the intermediate transfer medium of each example and comparative example under default conditions, and then Using the same printer, the intermediate transfer media of Examples 1 to 10 and Comparative Examples 1 to 10 were overlaid on the PVC card (DNP) to transfer the transfer layer (peeling layer, protective layer, receiving layer). Prints of Examples 1 to 10 and Comparative Examples 1 to 10 were formed. The prints were worn using a wearer wheel CS-10F with a Taber abrasion tester, and the wearer wheel was polished every 250 times with a load of 500 gf, for a total of 1500 times. The surface condition was visually observed after polishing, and durability was evaluated according to the following evaluation criteria. The evaluation results are shown in Table 1.

(Creation of thermal transfer sheet)
Using an easily adhesive-treated polyethylene terephthalate film having a thickness of 4.5 μm as a base material, a coating solution for a heat-resistant active layer having the following composition was applied on the base material to a dry weight of 0.8 g / m ² , A heat resistant active layer was formed. Next, on the other side of the substrate, the yellow dye layer coating liquid, the magenta dye layer coating liquid, and the cyan dye layer coating liquid each have a dry coating amount of 0.6 g / m ^2. In this manner, coating was carried out in the surface order to form a dye layer to obtain a thermal transfer sheet.

<Coating fluid for heat-resistant active layer>
・ 2.0 parts of polyvinyl butyral resin (SREC BX-1 Sekisui Chemical Co., Ltd.)
・ 9.2 parts of polyisocyanate (Bernock D750 Dainippon Ink & Chemicals, Inc.)
・ Phosphate surfactant 1.3 parts (Pricesurf A208N Daiichi Kogyo Seiyaku Co., Ltd.)
・ Talc 0.3 part (Microace P-3 Nippon Talc Industry Co., Ltd.)
・ Toluene 43.6 parts ・ Methyl ethyl ketone 43.6 parts

<Coating solution for yellow dye layer>
-Dye represented by the following formula: 4.0 parts-Polyvinyl acetal resin: 3.5 parts (ESREC KS-5 Sekisui Chemical Co., Ltd.)
・ Polyethylene wax 0.1 part ・ Methyl ethyl ketone 45.0 parts ・ Toluene 45.0 parts

<Coating liquid for magenta dye layer>
・ Disperse dye (dispersed thread 60) 1.5 parts ・ Disperse dye (dispers violet 26) 2.0 parts ・ Polyvinyl acetal resin 4.5 parts (SREC KS-5 Sekisui Chemical Co., Ltd.)
・ Polyethylene wax 0.1 part ・ Methyl ethyl ketone 45.0 parts ・ Toluene 45.0 parts

<Cyan dye layer coating solution>
-Disperse dye (Solvent Blue 63) 4.0 parts-Polyvinyl acetal resin 3.5 parts (S-REC KS-5 Sekisui Chemical Co., Ltd.)
・ Polyethylene wax 0.1 part ・ Methyl ethyl ketone 45.0 parts ・ Toluene 45.0 parts

<Evaluation criteria>
◎ ・ ・ ・ The image is not scraped at all.
○: The image is almost not scraped.
Δ: The image is cut to some extent, but there is no problem in use.
X: The image is considerably shaved.

<< Foil breakability (tailing) test >>
The foil breakability (tailing) of the printed materials of Examples 1 to 10 and Comparative Examples 1 to 10 was confirmed visually, and the foil breakability was evaluated according to the following evaluation criteria. The evaluation results are shown in Table 1. The tailing means the length of the transfer layer that starts from the boundary between the transfer region and the non-transfer region of the transfer layer and protrudes from the boundary to the non-transfer region side.
<Evaluation criteria>
A: The amount of tailing is 0.5 mm or less.
○: The amount of tailing is 1 mm or less.
Δ: The amount of tailing is 2 mm or less.
X: The amount of tailing is larger than 2 mm and smaller than 5 mm.
XX: The amount of tailing is 5 mm or more.

<< Plasticizer resistance test >>
A vinyl chloride sheet (Altron # 430, Mitsubishi Resin Co., Ltd.) was cut out to 5 cm × 5 cm, and this was overlaid with the prints of the Examples and Comparative Examples obtained above, and a load of 1750 g was applied at 82 ° C. Stored in the environment for 8 hours. Thereafter, it was visually observed whether the image of the printed matter was transferred to the vinyl chloride sheet, and plasticizer resistance was evaluated based on the following evaluation criteria. The evaluation results are also shown in Table 1.
<Evaluation criteria>
A: The image of the printed matter does not move at all on the vinyl chloride sheet.
○ The image of the printed matter has shifted to a vinyl chloride sheet, but the image of the printed matter has not faded.
Δ: The image of the printed matter has shifted slightly to the vinyl chloride sheet, and the image of the printed matter has also faded slightly.
X: The image of the printed matter has moved considerably to the vinyl chloride sheet, and the image of the printed matter has also faded.

<< Glossiness Evaluation Test >>
The glossiness of the printed materials of Examples 1 to 10 and Comparative Examples 1 to 10 was visually confirmed, and evaluated according to the following evaluation criteria. The evaluation results are also shown in Table 1.
<Evaluation criteria>
○ ・ ・ ・ No roughness and high gloss.
Δ: Although there is some roughness, it is at a level where there is no problem in use.
X: There is much roughness and there is no glossiness.

  As is clear from Table 1, an intermediate containing a mixed binder resin having a storage elastic modulus G ′ at 35 ° C. and 70 ° C. to 90 ° C. within the scope of the present invention, and a filler having a particle size of 1 nm to 200 nm. According to the transfer medium, the evaluation was excellent in durability and foil breakage. Moreover, it turns out that it is excellent also in plasticizer resistance and glossiness. On the other hand, in the intermediate transfer medium containing the binder resin whose protective layer has a storage elastic modulus G ′ at 35 ° C. and a storage elastic modulus G ′ at 70 ° C. to 90 ° C. outside the scope of the present invention, It turns out that both cannot be satisfied. Moreover, even if it contains a mixed binder resin whose storage elastic modulus G ′ at 35 ° C. and 70 ° C. to 90 ° C. is within the scope of the present invention, it does not contain a filler having a particle size of 1 nm to 200 nm. It can be seen that the medium cannot sufficiently satisfy the foil cutting property or cannot obtain a sufficient glossiness.

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Transfer layer 3 ... Release layer 4 ... Protective layer 5 ... Receiving layer 6 ... Plasticizer-resistant layer 10 ... Intermediate transfer medium

Claims (3)

An intermediate transfer medium in which a protective layer and a receiving layer are laminated on one side of a substrate,
The protective layer contains two or more binder resins and a filler,
The storage elastic modulus G ′ at 70 ° C. to 90 ° C. of the mixed binder resin obtained by mixing the two or more binder resins is in the range of 1.0 × 10 ⁵ Pa to 1.0 × 10 ⁹ Pa, 35 The storage elastic modulus G ′ at ° C. exceeds 1.0 × 10 ⁹ Pa,
The mixed binder resin includes a binder resin having a number average molecular weight (Mn) of 8000 to 30000 and a glass transition temperature (Tg) of 35 ° C. to 60 ° C.
An intermediate transfer medium, wherein the filler has a particle size of 1 nm to 200 nm.   The intermediate transfer medium according to claim 1, wherein the filler is contained in a range of 1% by mass to 35% by mass with respect to the total solid content of the protective layer.   The binder resin having a number average molecular weight (Mn) of 8000 to 30000 and a glass transition temperature (Tg) of 35 ° C. to 60 ° C. is contained in an amount of 10% by mass or more based on the total solid content of the mixed binder resin. The intermediate transfer medium according to claim 1 or 2, wherein

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