Method for producing recording material and method for producing transfer material, and inkjet ink

Abstract

To provide a method for producing a recording material allowing visual confirmation at the time of ink attachment and subsequently enabling formation of a transparent coating film through decolorization.SOLUTION: A method for producing a recording material comprises a non-decolorizable ink attachment step for applying, by an inkjet system, a non-decolorizable ink containing a non-decolorizable colorant onto a recording medium, a decolorizable ink attachment step for applying, by an inkjet system, a decolorizable ink containing a decolorizable colorant and a color-developing agent onto a coating film of the non-decolorizable ink, and a drying step for drying the decolorizable ink by heating to form a transparent coating film of the decolorizable ink.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing a recorded material, a method for producing a transferred material, and an inkjet ink. [Background technology]

[0002] Conventionally, techniques for recording images or the like on a recording medium such as film using aqueous inks have been known. For example, Patent Document 1 discloses a recording method including a non-white ink applying step of applying a non-white ink composition to a recording medium, a white ink applying step of applying a white ink composition to the recording medium that has been subjected to the non-white ink applying step, and a clear ink applying step of applying a clear ink composition to the recording medium that has been subjected to the white ink applying step. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-17005 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the above-mentioned conventional techniques, it is difficult to visually confirm the state of ejection of clear ink, and it is particularly difficult to confirm whether or not there is ejection failure of clear ink on white ink. One aspect of the present invention aims to realize a method for producing a recorded matter in which the state of ink deposition can be visually confirmed, but the ink can then be erased to form a transparent coating film. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, a method for producing a recorded matter according to one aspect of the present invention includes a non-erasable ink applying step of applying a non-erasable ink containing a non-erasable colorant to a recording medium by an inkjet method, an erasable ink applying step of applying an erasable ink containing a erasable colorant and a color developer onto a coating film of the non-erasable ink by an inkjet method, and a drying step of drying the erasable ink by heating to form a transparent coating film of the erasable ink.

[0006] An inkjet ink according to an embodiment of the present invention includes a decolorizable colorant, a color developer, and a resin, wherein the resin has a glass transition temperature of 30°C or lower and a weight average molecular weight of 10,000 to 700,000. [Effects of the Invention]

[0007] According to one aspect of the present invention, it is possible to provide a method for producing a recorded matter in which the ink can be visually confirmed when it is applied, but the ink then fades to form a transparent coating film. DETAILED DESCRIPTION OF THE INVENTION

[0008] An embodiment of the present invention will be described in detail below. In this specification, unless otherwise specified, "A to B" representing a numerical range means "greater than or equal to A and less than or equal to B." Furthermore, "(meth)acrylic acid" means acrylic acid or methacrylic acid, and "(meth)acrylate" means acrylate or methacrylate. The same applies to terms such as "(meth)acryloxy" and "(meth)acryloyl." Furthermore, a "structural unit derived from" corresponds to a structure in which the ethylenically unsaturated double bond of each monomer component is opened (a structure in which the double bond (C=C) becomes a single bond (-C-C-)).

[0009] [1. Manufacturing method of recorded matter] A method for producing a recorded matter according to one embodiment of the present invention includes a non-erasable ink applying step of applying a non-erasable ink containing a non-erasable colorant to a recording medium by an inkjet method, an erasable ink applying step of applying an erasable ink containing a erasable colorant and a color developer onto a coating film of the non-erasable ink by an inkjet method, and a drying step of drying the erasable ink by heating to form a transparent coating film of the erasable ink.

[0010] Images and the like can be formed by applying non-erasable ink to a recording medium. Here, as in the technology described in Patent Document 1, clear ink that does not affect the image may also be applied. However, because clear ink is difficult to visually confirm, there is a risk that ejection defects may not be noticed immediately after the clear ink is applied, and the ejection defects may only be discovered after the print job has progressed. A method for producing a recorded product according to one embodiment of the present invention uses an erasable ink containing an erasable colorant and a color developer. This erasable ink is colored when ejected, so it can be visually confirmed. It then undergoes a drying process and is erased, so it can be used in the same way as clear ink.

[0011] In this specification, a decolorizable colorant refers to a colorant that has the property of being decolorized by a stimulus such as heating. On the other hand, a non-decolorizable colorant refers to a colorant that does not have the property of being decolorized by a stimulus such as heating. Furthermore, a recorded matter refers to a recording medium on which a non-decolorizable ink and a decolorizable ink are printed. In a recorded matter, a coating film (e.g., an image) of non-decolorizable ink is formed on the recording medium, and a transparent coating film of decolorizable ink is formed on the coating film of non-decolorizable ink. The transparent coating film may be provided only in the area where the image is formed, or may be provided in addition to the area where the image is formed and around it. The recorded matter may be a transfer medium used for transfer to a transfer target material.

[0012] The recorded matter preferably has an ink-receiving layer on the surface of the recording medium on which the image is formed. That is, the recorded matter preferably has an ink-receiving layer between the recording medium and the image. By providing the ink-receiving layer, it is possible to prevent the non-erasable ink from flowing or crumbling, and it is also possible to further increase the durability of the image after it has been transferred to a receiving material. When the recorded matter has an ink-receiving layer, some or all of the non-erasable ink may be absorbed by the ink-receiving layer.

[0013] The ink-receiving layer can be formed by coating a recording medium (or a recording medium provided with a release layer, which will be described later) with a solution containing a resin for forming the ink-receiving layer. Examples of the resin include (meth)acrylic resins such as (meth)acrylic ester resins and (meth)acrylic ester-styrene copolymer resins; olefin resins such as polyethylene resins and polypropylene resins; silicone resins; and polyvinyl alcohol resins.

[0014] The thickness of the ink-receiving layer is not particularly limited, but is preferably 30 nm or more, more preferably 100 nm or more, from the viewpoint of suppressing the flow of non-erasable ink, and is preferably 20 μm or less, more preferably 10 μm or less, from the viewpoint of cost.

[0015] The recorded matter may also have a release layer provided on at least one surface of the recording medium. That is, the recorded matter may have a release layer between the recording medium and the image (preferably the ink-receiving layer) and / or on the side of the recording medium opposite the surface on which the image is formed. By providing a release layer between the recording medium and the image (preferably the ink-receiving layer), the recording medium can be easily peeled from the image, making it easier to transfer the image from the recorded matter to a transfer-receiving material. Furthermore, by providing a release layer on the side opposite the surface on which the image is formed, blocking between the recorded matters can be suppressed when the recorded matters are stacked.

[0016] The release layer is preferably a layer obtained by coating at least one surface of the recording medium with a release agent, such as a polyethylene wax-based release agent, a silicone-based release agent, or a fluorine-based release agent.

[0017] The thickness of the release layer is not particularly limited, but is preferably 10 nm or more, more preferably 30 nm or more, from the viewpoint of further improving transferability, and is preferably 2 μm or less from the viewpoint of reducing bulk when made into a roll-shaped recording material.

[0018] Sheets or films in which an ink-receiving layer and / or a release layer are provided on a recording medium are commercially available, and the recorded material may be formed using such commercially available products, such as DTF Transfers film (manufactured by One More Buck) and PET film roll DFR-600 (manufactured by Image Magic).

[0019] In this specification, the term "image" includes characters and patterns. The image may be a single layer or a multilayer. For example, by providing a layer of white ink on a layer of color ink, good color development can be achieved even when the image is transferred onto a dark-colored material such as black.

[0020] <1-1. Non-erasable ink application process> The non-erasable ink application step is a step of applying a non-erasable ink containing a non-erasable colorant to a recording medium by an inkjet method. An example of a method for applying a non-erasable ink to a recording medium by an inkjet method is a method in which the non-erasable ink is ejected from an inkjet head of an inkjet ejection device. This allows the non-erasable ink to be applied to a predetermined portion of the recording medium, forming an image or the like.

[0021] The recording medium is not particularly limited, but is preferably made of a material that does not shrink easily during the drying process described below. Specific examples of the recording medium include metal, wood, plastic, and paper. Examples of the metal include aluminum and copper, with aluminum being preferred from the standpoint of cost. Examples of the plastic include polyolefin resin, polyester resin, polyamide resin, and polycarbonate resin, with polyester resin being preferred from the standpoint of cost, and aromatic polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate being more preferred. Examples of the paper include plain paper, high-quality paper, and coated paper.

[0022] In particular, the recording medium is preferably plastic or paper from the viewpoint of cost, and more preferably polyester resin from the viewpoint of good heat resistance, more preferably aromatic polyester, and most preferably polyethylene terephthalate.

[0023] The recording medium may have a single layer structure or a laminated structure. The recording medium is preferably a sheet or film to facilitate use of the recorded matter. The thickness of the recording medium is preferably 5 to 150 μm. When the recording medium is a film, the resulting transfer medium is also called a transfer film.

[0024] The ejection weight of the non-erasable ink per unit area is not particularly limited, but is preferably 0.1 to 20 mg / cm. 2 is preferred, and 0.5 to 10 mg / cm 2

[0046] It is more preferable that the wet rubbing fastness be in the range of 1 / 200. By forming an image in this range, a transferred product having even more excellent texture and wet rubbing fastness tends to be obtained. In this specification, the wet rubbing fastness means a property that can be evaluated by a wet rubbing test according to the method specified in JIS L0849.

[0025] The hue of the non-erasable ink is not particularly limited and may be selected from black, white, and chromatic colors. Chromatic colors include the three subtractive primary colors of magenta, yellow, and cyan, as well as colors of different shades such as light cyan, dark yellow, light magenta, and light black. Furthermore, the non-erasable ink may have one or more hues selected from red, blue, orange, green, and violet. The hue of the non-erasable ink can be controlled by the pigment described below. The term "non-erasable ink" encompasses the color ink and white ink described below. In this specification, color ink refers to ink containing a non-white colorant, and white ink refers to ink containing a white colorant. In one embodiment, the non-erasable colorant is a white colorant.

[0026] Examples of non-bleachable coloring materials include pigments and dyes, with pigments being particularly preferred. The pigment is not particularly limited, and pigments used in ordinary inkjet textile printing color inks can be used. Examples of the pigment include organic pigments and inorganic pigments, which can be used alone or in combination of two or more. If necessary, these can also be used in combination with an extender pigment.

[0027] Examples of organic pigments include benzidine, azo pigments (such as Hansa Yellow), diazo pigments, azomethine pigments, methine pigments, anthraquinone pigments, phthalocyanine pigments (such as Phthalocyanine Blue), perinone pigments, perylene pigments, diketopyrrolopyrrole pigments, thioindigo pigments, iminoisoindoline pigments, isoindolinone pigments (such as iminoisoindolinone), dioxazine pigments, quinacridone pigments (such as quinacridone red and quinacridone violet), flavanthrone pigments, indanthrone pigments, anthrapyrimidine pigments, carbazole pigments, monoarylide yellow, diarylide yellow, benzimidazolone yellow, tolyl orange, naphthol orange, and quinophthalone pigments.

[0028] The hue of the organic pigment is not particularly limited, and any pigment exhibiting the above-mentioned chromatic hue can be used. Specific examples of such organic pigments include CI Pigment Yellow, CI Pigment Red, CI Pigment Orange, CI Pigment Violet, CI Pigment Blue, and CI Pigment Green.

[0029] Examples of inorganic pigments include titanium dioxide, antimony trioxide, zinc oxides such as zinc white, lithopone, white lead, red iron oxide, black iron oxide, chromium oxide green, carbon black, yellow lead, molybdenum red, ferric ferrocyanide (Prussian blue), ultramarine, and lead chromate. Other examples of inorganic pigments include flat-shaped pigments such as mica, clay, aluminum powder, talc, and aluminum silicate, as well as extender pigments such as calcium carbonate, magnesium hydroxide, aluminum hydroxide, barium sulfate, and magnesium carbonate. Examples of carbon black include furnace black, thermal lamp black, acetylene black, and channel black.

[0030] Among inorganic pigments, preferred white pigments are titanium dioxide, antimony trioxide, zinc oxide such as zinc white, lithopone, white lead, calcium carbonate, magnesium hydroxide, aluminum hydroxide, barium sulfate, magnesium carbonate, clay, talc, and aluminum silicate. Of these, titanium dioxide is preferred from the viewpoint of its high refractive index and excellent hiding power. Of titanium dioxide, titanium dioxide having a rutile crystal structure is preferred.

[0031] Preferred non-white pigments include the above organic pigments, red iron oxide, black iron oxide, chromium oxide green, carbon black, yellow lead, molybdenum red, ferric ferrocyanide (Prussian blue), ultramarine, and lead chromate.

[0032] The average particle size of the pigment is preferably 10 to 1,000 nm, and more preferably 20 to 500 nm, from the viewpoints of dispersion stability and color development or hiding power. In the case of a white pigment, the average particle size is preferably 100 to 500 nm, from the viewpoint of superior hiding power, with the lower limit being more preferably 150 nm or more, and even more preferably 200 nm or more, and the upper limit being more preferably 450 nm or less, and even more preferably 400 nm or less. In the case of a non-white pigment, the average particle size is preferably 20 to 200 nm, particularly from the viewpoint of color development, with the lower limit being more preferably 40 nm or more, and even more preferably 50 nm or more, and the upper limit being more preferably 150 nm or less, and even more preferably 100 nm or less.

[0033] The average particle size of the pigment can be measured by a laser diffraction / scattering particle size distribution analyzer or dynamic light scattering. For example, the cumulant average particle size measured by dynamic light scattering, as shown in the examples below, can be used. However, in cases where measurement by dynamic light scattering is difficult, such as with black pigments, the 50% particle size in the volume-based particle size distribution measured by a laser diffraction / scattering particle size distribution analyzer can be used as the average particle size.

[0034] It is preferable that the pigment is dispersed and stabilized in the ink with a dispersant. For this reason, the non-erasable ink is preferably produced by mixing the pigment, dispersant, and solvent, and dispersing the mixture using a bead mill or the like to prepare a pigment dispersion in which the pigment is dispersed in the solvent, and then mixing this with the resin and any optional components described below.

[0035] Examples of the dispersant include poly(meth)acrylic acid (salts) such as poly(meth)acrylic acid and poly(meth)acrylate salts; copolymers of (meth)acrylic acid (salts) with one or more of the above-mentioned monomer components other than (meth)acrylic acid (salts), such as (meth)acrylic acid alkyl esters, (meth)acrylamide, styrene, maleic acid, maleic anhydride, maleic acid esters, and vinyl acetate; polyvinyl alcohol; and polyvinylpyrrolidone.

[0036] The solvent in the pigment dispersion is preferably an aqueous solvent, and examples of the aqueous solvent include water and a mixed solvent of water and a water-soluble organic solvent described below.

[0037] The content of the pigment in the non-erasable ink is preferably 1 to 50% by mass, more preferably 2 to 35% by mass. In particular, when the pigment is a white pigment, the content of the white pigment in the non-erasable ink is preferably 5 to 40% by mass, more preferably 10 to 30% by mass. Furthermore, when the pigment is an organic pigment, the content of the organic pigment in the solid content of the non-erasable ink is preferably 1 to 30% by mass, more preferably 2 to 15% by mass.

[0038] The non-erasable ink may contain a resin. The type of resin contained in the non-erasable ink is not particularly limited, and examples thereof include vinyl resins, acrylic resins, polyester resins, olefin resins, urethane resins, fluorine resins, silicone resins, epoxy resins, phenoxy resins, phenol resins, and xylene resins. Among these, acrylic resins and / or polyester resins are preferred, and acrylic resins are particularly preferred.

[0039] In particular, it is preferable that the resin used in the non-erasable ink is a resin of the same type as the resin used in the erasable ink. That is, when an acrylic resin and / or a polyester resin is used as the erasable ink, it is preferable that the resin used in the non-erasable ink is also an acrylic resin and / or a polyester resin. When an acrylic resin is used as the erasable ink, it is more preferable that the resin used in the non-erasable ink is also an acrylic resin. When a polyester resin is used as the erasable ink, it is more preferable that the resin used in the non-erasable ink is also a polyester resin. By using these combinations, the interface between the transparent coating film formed from the erasable ink and the image formed from the non-erasable ink in the recorded product and the transferred product is less likely to peel, resulting in improved transferability and robustness of the resulting transferred product.

[0040] The acrylic resin used in the non-erasable ink may be a conventionally known acrylic resin. Among these, a resin containing a structural unit derived from a (meth)acrylic monomer is preferred. Specific examples of the (meth)acrylic monomer are the same as those used in the erasable ink described below. The (meth)acrylic monomer preferably contains at least one selected from the group consisting of alkyl (meth)acrylate, (meth)acrylic acid, and hydroxyalkyl (meth)acrylate, and more preferably contains all of (meth)acrylic acid, alkyl (meth)acrylate, and hydroxyalkyl (meth)acrylate.

[0041] The alkyl(meth)acrylate is preferably an alkyl(meth)acrylate having an alkyl group with 1 to 18 carbon atoms, and more preferably an alkyl(meth)acrylate having an alkyl group with 4 to 12 carbon atoms. The content of the alkyl(meth)acrylate-derived structural units relative to the total of 100% by mass of structural units derived from all monomer components constituting the acrylic resin used in the non-erasable ink is preferably 20 to 99% by mass, more preferably 30 to 98% by mass, and even more preferably 40 to 95% by mass.

[0042] The content of the (meth)acrylic acid-derived structural unit relative to the total of all monomer components constituting the acrylic resin used in the non-erasable ink (100% by mass) is preferably 0.1 to 5% by mass, more preferably 0.5 to 4% by mass, and even more preferably 1.0 to 3% by mass. By adjusting the content within the above range, the rub fastness and washing fastness of the resulting transferred product can be further improved.

[0043] The content of the hydroxyalkyl (meth)acrylate-derived structural unit relative to the total of all the monomer components constituting the acrylic resin used in the non-erasable ink (100% by mass) is preferably 0.1 to 5% by mass, more preferably 0.3 to 4% by mass, and even more preferably 0.5 to 3% by mass. By adjusting the content within the above range, the water resistance of the resulting transfer product can be improved.

[0044] The acrylic resin used in the non-erasable ink may further contain a structural unit derived from a styrene-based monomer. The total content of structural units derived from (meth)acrylic monomers and structural units derived from styrene-based monomers is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 95% by mass or more, relative to 100% by mass of the total of structural units derived from all monomer components constituting the acrylic resin used in the non-erasable ink. Specific examples of the styrene-based monomer are the same as those of the styrene-based monomers used in the erasable ink described below.

[0045] The acrylic resin used for the non-erasable ink may further contain a structural unit derived from a monomer other than a (meth)acrylic monomer and a styrene monomer. Examples of the monomer other than a (meth)acrylic monomer and a styrene monomer include the acid group-containing monomer (excluding (meth)acrylic acid) and other monomers used in the erasable ink described below.

[0046] The polyester resin used in the non-erasable ink may be a conventionally known polyester resin. The polyester resin is preferably a condensation polymer of an aromatic dicarboxylic acid and a diol compound. Specific examples of the aromatic dicarboxylic acid and the diol compound are the same as those exemplified in the description of the polyester resin used in the erasable ink, which will be described later.

[0047] The weight-average molecular weight (Mw) of the resin used in the non-erasable ink is not particularly limited, but from the viewpoint of suppressing the flow of the non-erasable ink after printing, it is preferably 50,000 or more, more preferably 300,000 or more, even more preferably 550,000 or more, and particularly preferably 600,000 or more. From the viewpoint of improving film-forming properties and water resistance, the upper limit of the weight-average molecular weight of the resin used in the non-erasable ink is preferably 5,000,000 or less.

[0048] The glass transition temperature (Tg) of the resin used in the non-erasable ink is not particularly limited, but from the viewpoint of further improving the texture of the resulting transferred product, it is preferably −50 to 10°C, more preferably −45 to 5°C, and even more preferably −40 to 3°C.

[0049] In the non-erasable ink, the resin is preferably contained as emulsion particles. The preferred aspects of the composition and physical properties of the resin constituting the emulsion particles are the same as those of the emulsion particles in the erasable ink described below.

[0050] The content of resin (preferably emulsion particles) in the non-erasable ink is, for example, 5 to 40% by mass, preferably 8 to 30% by mass, and more preferably 10 to 25% by mass. By adjusting the resin content within the above range, the viscosity of the non-erasable ink can be maintained within an appropriate range.

[0051] The non-erasable ink preferably further contains a solvent. As the solvent, organic solvents and aqueous solvents can be suitably used, but from the viewpoint of reducing the environmental load, it is preferable to use an aqueous solvent. Examples of aqueous solvents include water and mixed solvents of water and water-soluble organic solvents. From the viewpoint of improving moisture retention and compatibility with the resin, the aqueous solvent contained in the non-erasable ink preferably contains a water-soluble organic solvent. Preferred aspects of the type and content of the water-soluble organic solvent are the same as preferred aspects of the type and content of the water-soluble organic solvent in the erasable ink described below.

[0052] The content of the solvent in the non-erasable ink is not particularly limited and may be set according to the desired viscosity of the non-erasable ink, but is, for example, 40 to 90% by mass, preferably 50 to 88% by mass, and more preferably 55 to 85% by mass.

[0053] The non-erasable ink may further contain a crosslinking agent. The use of a crosslinking agent can form a crosslinked structure through interaction with components contained in the non-erasable ink, such as a resin, or through a chemical reaction, thereby forming a tough coating film, which is presumably responsible for further improving the wet rub fastness and washing fastness of the resulting transfer. Examples of crosslinking agents that can be used in the non-erasable ink include the compounds exemplified below as crosslinking agents that can be used in the erasable ink, and preferred embodiments thereof are also the same.

[0054] The content of the crosslinking agent is not particularly limited, but is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 8 parts by mass, and even more preferably 0.2 to 5 parts by mass, relative to 100 parts by mass of the resin.

[0055] The non-erasable ink may further contain a surfactant. Examples of surfactants that can be used in the non-erasable ink include the compounds exemplified below as surfactants that can be used in the erasable ink, and preferred embodiments thereof are also the same. The content of the surfactant is not particularly limited, but is preferably 0.01 to 2% by mass, and more preferably 0.1 to 1% by mass, relative to 100% by mass of the non-erasable ink.

[0056] The non-erasable ink may contain other components in addition to those described above, provided that the object of the present invention is not impaired. For example, the ink may contain appropriate amounts of additives such as leveling agents, UV absorbers, UV stabilizers, thickeners, humectants, plasticizers, stabilizers, defoamers, dyes, antioxidants, crosslinking accelerators, pH adjusters, and preservatives. When the above-mentioned other components are added, their content is not particularly limited, but is preferably 2% by mass or less, and more preferably 1% by mass or less, relative to 100% by mass of the non-erasable ink. Furthermore, to achieve the desired effect, the content is preferably 0.01% by mass or more, and more preferably 0.05% by mass or more.

[0057] The non-erasable ink applying step may include a white ink applying step of applying a white ink to the recording medium by inkjet printing, or may include a color ink applying step of applying a color ink to the recording medium by inkjet printing. The non-erasable ink applying step may also include a color ink applying step of applying a color ink to the recording medium by inkjet printing, and a white ink applying step of applying a white ink onto the color ink coating on the recording medium by inkjet printing. By performing these steps, a white background layer is formed between the transfer material and the image in the resulting transferred product, resulting in excellent color development, particularly when using a dark-colored transfer material. Furthermore, by applying white ink onto a color ink coating and then forming a transparent erasable ink coating on top of that, a transferred product having an image with excellent color development and adhesion can be obtained.

[0058] The manufacturing method may include a non-erasable ink drying step of drying the coating of the non-erasable ink prior to the erasable ink application step. The non-erasable ink drying step is a step of evaporating some or all of the components (i.e., solvent) of the non-erasable ink applied to the recording medium, excluding the solid content. This prevents the non-erasable ink from flowing, thereby enabling the production of clear images. Furthermore, drying the non-erasable ink makes it difficult for the erasable ink to penetrate the non-erasable ink, thereby improving adhesion during transfer.

[0059] In the non-erasable ink drying step, of 100% by mass of the components of the non-erasable ink excluding solids, preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more is evaporated. By adjusting the evaporation amount within the above range, it is possible to prevent the erasable ink from flowing in the erasable ink application step described below. Furthermore, in the non-erasable ink drying step, of 100% by mass of the components of the non-erasable ink excluding solids, preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, and particularly preferably 50% by mass or less or 40% by mass or less is evaporated. By adjusting the evaporation amount within the above range, the non-erasable ink layer and the erasable ink layer are appropriately mixed at the interface between them, preventing peeling at the interface during transfer printing, thereby further improving transferability. The conditions for obtaining the desired evaporation amount can be determined by ejecting a fixed weight of non-erasable ink onto a substrate using a non-erasable ink with a known solid content concentration, measuring the total weight of the ink and recording medium after drying, and the weight of the recording medium alone using a precision balance, and then calculating the weight.The non-erasable ink drying process can be carried out under the same conditions.

[0060] The device for carrying out the non-erasable ink drying step is not particularly limited, and examples thereof include contact heating devices such as platen heaters and rubber heaters, and non-contact heating devices such as hot air heaters, infrared heaters, and halogen heaters. Among these, from the viewpoint of uniform drying, contact heating devices are preferred, and platen heaters are more preferred. For example, the non-erasable ink can be dried by heating the back surface of the recording medium with a contact heating device. In this specification, the surface of the recording medium on which the non-erasable ink is applied is referred to as the front surface of the recording medium, and the surface opposite to the surface on which the non-erasable ink is applied is referred to as the back surface of the recording medium.

[0061] The evaporation amount can be adjusted by controlling the heating temperature, heating time, hot air temperature, air volume, etc. The heating temperature in the non-erasable ink drying step is preferably 30°C or higher, more preferably 40°C or higher, from the viewpoint of shortening the heating time. Furthermore, if the heating temperature is too high, the heat may be transferred to the inkjet head, causing nozzle clogging. Therefore, the heating temperature is preferably 100°C or lower, more preferably 90°C or lower, even more preferably 80°C or lower, and particularly preferably 70°C or lower.

[0062] The non-erasable ink drying step may be carried out simultaneously with the non-erasable ink applying step, may be carried out after the non-erasable ink applying step, or may be carried out simultaneously with the non-erasable ink applying step and after the non-erasable ink applying step. When the non-erasable ink drying step is carried out simultaneously with the non-erasable ink applying step, it may be carried out continuously from the start to the end of the non-erasable ink applying step, or may be carried out intermittently, but it is preferably carried out continuously.

[0063] <1-2. Erasable ink application process> The erasable ink application step is a step of applying an erasable ink containing an erasable colorant and a color developer onto a coating film of non-erasable ink by an inkjet method. In the erasable ink application step, the erasable colorant is colored by the action of the color developer. Examples of the erasable colorant include colorants that are erased by a stimulus. Examples of such stimuli include heating, light irradiation, and contact with an acid or alkali. Preferably, the erasable colorant is an erasable colorant that is erased by heating. If the erasable colorant is an erasable colorant that is erased by heating, it can be easily erased by heating and drying.

[0064] From the viewpoint of availability, the decolorizable colorant is preferably a leuco dye. Leuco dyes are dyes that can become colored or colorless by changing their chemical structure. Examples of leuco dyes include triphenylmethane compounds, diphenylmethane compounds, spiropyran compounds, fluoran compounds, and rhodamine lactam compounds. Among these, compounds having a lactone ring in the molecule, such as fluoran compounds and rhodamine lactam compounds, are preferred.

[0065] Examples of color developers include compounds having a phosphoric acid group and compounds having a phenolic hydroxyl group. Examples of compounds having a phosphoric acid group include phosphoric acid, phosphoric acid monoesters, and phosphoric acid diesters, such as monoalkyl phosphoric acid esters, dialkyl phosphoric acid esters, polyoxyethylene monoalkyl phosphoric acid esters, and polyoxyethylene dialkyl phosphoric acid esters. Examples of compounds having a phenolic hydroxyl group include hydroxyacetophenone-based compounds, hydroxybenzophenone-based compounds, gallic acid ester-based compounds, benzenetriol-based compounds, bisphenol-based compounds, triphenol-based compounds, and cresol-based compounds, such as dihydroxyacetophenone, trihydroxyacetophenone, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, dihydrobenzoic acid, bisphenols (such as bisphenol A and bisphenol Z), hydroxyphenylalkyl-benzotriazole, methylenetrith-p-cresol, and alkyl gallate esters.

[0066] An example of an apparatus for carrying out the erasable ink application step is an inkjet ejection apparatus similar to that used in the non-erasable ink application step. When an inkjet ejection apparatus is used, the erasable ink can be printed by ejecting the erasable ink from an inkjet head and applying the erasable ink onto the coating film of non-erasable ink formed in the non-erasable ink application step. This forms a coating film of erasable ink on the coating film of non-erasable ink.

[0067] By using an inkjet ejection device equipped with a plurality of inkjet heads, it is possible to continuously print with non-erasable ink and with erasable ink. For example, by installing an ink set containing one or more types of non-erasable ink and an erasable ink in the ink cartridges for each color of the inkjet ejection device and ejecting ink from each inkjet head corresponding to each ink cartridge, it is possible to continuously print with non-erasable ink and with erasable ink.

[0068] In the erasable ink application process, the amount of the erasable ink applied was 3.0 mg / cm 2 or more, preferably 4.0 mg / cm 2 More preferably, it is 5.0 mg / cm or more. 2 More preferably, it is 8.0 mg / cm or more. 2 From the viewpoint of ease of drying, the amount of decolorizable ink applied is 35 mg / cm 2 Preferably, it is 20 mg / cm or less. 2 More preferably, it is:

[0069] The erasable ink preferably contains a resin, an aqueous organic solvent, and water. By including a resin in the erasable ink, adhesive properties can be imparted, thereby improving transferability. The resin may be used alone or in combination of two or more.

[0070] The glass transition temperature (Tg) of the resin is, for example, 30°C or lower, preferably 20°C or lower, more preferably 15°C or lower, and even more preferably 10°C or lower. By adjusting the Tg of the resin within the above range, the texture of the resulting transferred product is excellent. The lower limit of the Tg of the resin is, for example, -50°C or higher, preferably -30°C or higher, more preferably -20°C or higher, and even more preferably -10°C or higher. When a recorded product is wound into a roll and stored, blocking due to the erasable ink can occur, but blocking can be suppressed by adjusting the lower limit of the Tg of the resin within the above range.

[0071] The Tg of a resin can be determined by differential scanning calorimetry (DSC). Specifically, for example, a DSC curve is created by heating and cooling the resin using a differential scanning calorimetry analyzer (NETZSCH "DSC 3500") in the following steps, and the midpoint glass transition temperature obtained from the DSC curve during the second heating cycle is taken as the Tg of the resin. (Step 1) The temperature is increased from -50°C to 150°C at a rate of 10°C / min and held at 150°C for 5 minutes. (Step 2) The temperature is decreased from 150°C to -50°C at a rate of 10°C / min and held at -50°C for 5 minutes. (Step 3) The temperature is increased from -50°C to 150°C at a rate of 10°C / min.

[0072] In addition, when the resin has a core-shell structure, multiple glass transition temperatures may be observed. In this case, it is sufficient that any one of the glass transition temperatures satisfies the above range, and it is preferable that all of the glass transition temperatures satisfy the above range.

[0073] Furthermore, when two or more resins are used, it is preferable that the Tg of the resin that is the main component satisfies the above range, and it is more preferable that the Tg of each of all the resins is within the above range. Note that the term "main component resin" refers to a resin that preferably accounts for 50% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more, of the total 100% by mass of the resins contained in the erasable ink.

[0074] The weight-average molecular weight of the resin contained in the erasable ink is 10,000 or more, preferably 20,000 or more, and may be 30,000 or more or 50,000 or more. By adjusting the weight-average molecular weight of the resin within the above range, it is possible to prevent the erasable ink from flowing after printing. Furthermore, the weight-average molecular weight of the resin is 700,000 or less, preferably 500,000 or less, more preferably 400,000 or less, and may be 350,000 or less or 300,000 or less. By adjusting the weight-average molecular weight of the resin within the above range and adjusting the Tg of the resin to 30° C. or less, the transferability during transfer printing and the wet rub fastness of the resulting transfer are excellent.

[0075] The weight-average molecular weight of the resin can be calculated by a standard polystyrene conversion method using gel permeation chromatography (GPC). Specifically, for example, a resin solution dissolved in tetrahydrofuran (THF) to a concentration of 0.2% by mass is used as a sample, and the weight-average molecular weight (polystyrene conversion) can be calculated from a gel permeation chromatography chart prepared using gel permeation chromatography (manufactured by Tosoh Corporation, product number: HLC-8320GPC, column: TSK-GEL SuperMultiporeHZ, eluent: THF) and a calibration curve prepared using standard polystyrene manufactured by Tosoh Corporation.

[0076] When two or more resins are used, it is sufficient that the weight average molecular weight of the resins as a mixture falls within the above range, but it is preferable that the weight average molecular weights of all the resins fall within the above range.

[0077] The type of resin contained in the erasable ink is not particularly limited, and examples thereof include vinyl resins, acrylic resins, polyester resins, olefin resins, urethane resins, fluorine resins, silicone resins, epoxy resins, phenoxy resins, phenol resins, xylene resins, etc. Among these, it is preferable that the erasable ink contains one or more resins selected from the group consisting of acrylic resins and polyester resins.

[0078] The acrylic resin is a resin containing structural units derived from (meth)acrylic monomers. The content of structural units derived from (meth)acrylic monomers relative to the total of structural units derived from all monomer components constituting the acrylic resin (100% by mass) is preferably 20% by mass or more, more preferably 30% by mass or more, even more preferably 40% by mass or more, and may be 70 or 85% by mass or more. The content of structural units derived from (meth)acrylic monomers may be 100% by mass or less, or may be 90% by mass or less. By adjusting the content of structural units derived from (meth)acrylic monomers within the above range, the wet rub fastness of the resulting transferred product is further improved.

[0079] Examples of the (meth)acrylic monomer include monofunctional (meth)acrylates and polyfunctional (meth)acrylates.

[0080] Examples of the monofunctional (meth)acrylate include: (Meth)acrylic acid; Alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, sec-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, 2-octyl (meth)acrylate, tridecyl (meth)acrylate, cyclohexyl (meth)acrylate, n-lauryl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate; Fluoroalkyl (meth)acrylates such as trifluoroethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, and octafluoropentyl (meth)acrylate; aralkyl (meth)acrylates such as benzyl (meth)acrylate, phenylethyl (meth)acrylate, methylbenzyl (meth)acrylate, and naphthylmethyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; Epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate and α-methylglycidyl (meth)acrylate; alkoxyalkyl group-containing (meth)acrylates such as methoxyethyl (meth)acrylate, methoxybutyl (meth)acrylate, ethoxybutyl (meth)acrylate, and trimethylolpropane tripropoxy (meth)acrylate; silyl group-containing (meth)acrylates such as γ-(meth)acryloyloxypropyltrimethoxysilane, γ-(meth)acryloyloxypropylhydroxysilane, and γ-(meth)acryloyloxypropylmethylhydroxysilane; carbonyl group-containing (meth)acrylates such as (meth)acryloxyalkylpropenal, acetonyl (meth)acrylate, diacetone (meth)acrylate, 2-hydroxypropyl (meth)acrylate acetylacetate, butanediol-1,4-acrylate acetylacetate, and 2-(acetoacetoxy)ethyl (meth)acrylate; (meth)acrylates containing an aziridinyl group, such as (meth)acryloylaziridine and 2-aziridinylethyl (meth)acrylate; oxo group-containing (meth)acrylates such as (di)ethylene glycol (methoxy) (meth)acrylates such as ethylene glycol (meth)acrylate, ethylene glycol methoxy (meth)acrylate, diethylene glycol (meth)acrylate, and diethylene glycol methoxy (meth)acrylate; Examples include piperidine group-containing (meth)acrylates such as 4-(meth)acryloyloxy-2,2,6,6-tetramethylpiperidine and 4-(meth)acryloyloxy-1,2,2,6,6-pentamethylpiperidine; and the like, and one or more of these can be selected and used.

[0081] Among these, the monofunctional (meth)acrylate preferably contains (meth)acrylic acid and / or an alkyl (meth)acrylate, and more preferably contains (meth)acrylic acid and an alkyl (meth)acrylate. The alkyl (meth)acrylate preferably contains an alkyl (meth)acrylate having an alkyl group with 1 to 18 carbon atoms, and more preferably contains an alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms. It is also a preferred embodiment to use two or more alkyl (meth)acrylates having different carbon numbers in combination. For example, there may be mentioned a combination of an alkyl(meth)acrylate having 1 to 3 carbon atoms and an alkyl(meth)acrylate having 4 to 18 carbon atoms, a combination of an alkyl(meth)acrylate having 4 to 6 carbon atoms and an alkyl(meth)acrylate having 7 to 18 carbon atoms, and a combination of an alkyl(meth)acrylate having 1 to 3 carbon atoms, an alkyl(meth)acrylate having 4 to 6 carbon atoms and an alkyl(meth)acrylate having 7 to 18 carbon atoms.

[0082] The content of the monofunctional (meth)acrylate-derived structural units relative to the total 100% by mass of structural units derived from all monomer components constituting the acrylic resin is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more. The content of the monofunctional (meth)acrylate-derived structural units may be 100% by mass or less, or may be 90% by mass or less.

[0083] Examples of the polyfunctional (meth)acrylate include: di(meth)acrylates of polyhydric alcohols having 1 to 10 carbon atoms, such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, ethylene oxide-modified 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, propylene oxide-modified neopentyl glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate; alkyl di(meth)acrylates having an added mole number of alkylene oxide groups having 2 to 4 carbon atoms of 2 to 50, such as polyethylene glycol di(meth)acrylate having an added mole number of ethylene oxide of 2 to 50, polypropylene glycol di(meth)acrylate having an added mole number of propylene oxide of 2 to 50, and tripropylene glycol di(meth)acrylate; Tri(meth)acrylates of polyhydric alcohols having 1 to 10 carbon atoms, such as ethoxylated glycerin tri(meth)acrylate, propylene oxide-modified glycerol tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol monohydroxytri(meth)acrylate, and trimethylolpropane triethoxytri(meth)acrylate; tetra(meth)acrylates of polyhydric alcohols having 1 to 10 carbon atoms, such as pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and ditrimethylolpropane tetra(meth)acrylate; Penta(meth)acrylates of polyhydric alcohols having 1 to 10 carbon atoms, such as pentaerythritol penta(meth)acrylate and dipentaerythritol (monohydroxy)penta(meth)acrylate; Hexa(meth)acrylates of polyhydric alcohols having 1 to 10 carbon atoms, such as pentaerythritol hexa(meth)acrylate; Epoxy group-containing (meth)acrylates such as bisphenol A di(meth)acrylate, 2-(2'-vinyloxyethoxyethyl)(meth)acrylate, and epoxy (meth)acrylate; Examples include polyfunctional (meth)acrylates such as urethane (meth)acrylate, and one or more of these can be selected and used.

[0084] The content of the structural unit derived from the polyfunctional (meth)acrylate relative to the total of 100% by mass of the structural units derived from all monomer components constituting the acrylic resin is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 1% by mass or less.

[0085] The acrylic resin preferably has a structural unit derived from an acid group-containing monomer. The acrylic resin has good stability when it contains a structural unit derived from an acid group-containing monomer. The acrylic resin may contain one type of structural unit derived from an acid group-containing monomer alone, or two or more types of structural units derived from an acid group-containing monomer.

[0086] The acid group-containing monomer may have at least one acid group and at least one polymerizable unsaturated group in the molecule. Examples of the acid group include a sulfo group and a carboxy group, with a carboxy group being preferred. The acid group-containing monomer may be the above-mentioned (meth)acrylic acid or other acid group-containing monomers. Specific examples of the acid group-containing monomer include unsaturated monocarboxylic acids such as (meth)acrylic acid, cinnamic acid, and crotonic acid; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, and citraconic acid; monoesters of unsaturated dicarboxylic acids such as maleic acid monomethyl ester, maleic acid monobutyl ester, itaconic acid monomethyl ester, and itaconic acid monobutyl ester; anhydrides of unsaturated dicarboxylic acids such as maleic anhydride; 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, and 2-acryloyloxyethyl hexahydrophthalic acid. Among these, unsaturated monocarboxylic acids are preferred, and (meth)acrylic acid is more preferred.

[0087] When the acrylic resin contains structural units derived from acid group-containing monomers, the content of the structural units derived from the acid group-containing monomers relative to the total 100% by mass of structural units derived from all monomer components constituting the acrylic resin is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more. The content of the structural units derived from the acid group-containing monomers is preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less.

[0088] The acrylic resin may further contain structural units derived from styrene-based monomers. The total content of structural units derived from (meth)acrylic monomers and structural units derived from styrene-based monomers relative to the total of structural units derived from all monomer components constituting the acrylic resin (100% by mass) is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 95% by mass or more, and may be 100% by mass.

[0089] Examples of the styrene-based monomer include styrene, α-methylstyrene, p-methylstyrene, tert-methylstyrene, chlorostyrene, vinyltoluene, 2-styrylethyltrimethoxysilane, and divinylbenzene, and one or more of these may be selected and used. The styrene-based monomer may have a functional group, such as an alkyl group (e.g., a methyl group or a tert-butyl group), a nitro group, a nitrile group, an alkoxyl group, an acyl group, a sulfone group, a hydroxyl group, or a halogen atom, present on the benzene ring constituting the styrene-based monomer. Among the styrene-based monomers, styrene is preferred from the viewpoint of improving water resistance.

[0090] The content of the styrene monomer-derived structural units relative to the total of 100% by mass of the structural units derived from all monomer components constituting the acrylic resin may be, for example, 10% by mass or more, or may be 30% by mass or more. The content of the styrene monomer-derived structural units is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less.

[0091] The acrylic resin may further have one or more structural units derived from monomers other than (meth)acrylic monomers, acid group-containing monomers, and styrene monomers (hereinafter, sometimes referred to as other monomers).

[0092] The other monomer is not particularly limited as long as it has at least one polymerizable unsaturated group in the molecule, and examples thereof include addition-polymerizable oxazolines such as 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, and 2-isopropenyl-5-ethyl-2-oxazoline; vinyl monomers such as vinyl acetate, vinyl chloride, and vinyl benzoate; acrylonitrile; (meth)acrylamide-based monomers such as (meth)acrylamide, N-monomethyl(meth)acrylamide, N-monoethyl(meth)acrylamide, and N,N-dimethyl(meth)acrylamide; and olefin-based monomers such as ethylene and propylene.

[0093] The acrylic resin can be produced by a conventionally known polymerization method, such as solution polymerization, bulk polymerization, suspension polymerization, or emulsion polymerization. Among these, emulsion polymerization is preferred. According to the emulsion polymerization method, an emulsion in which the acrylic resin is dispersed in an aqueous solvent as emulsion particles is obtained.

[0094] The polyester resin is not particularly limited as long as it is a polymer having an ester bond in the main chain, but is preferably a condensation polymer of an aromatic dicarboxylic acid and a diol compound. Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, and terephthalic acid. Examples of the diol compound include aliphatic diols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, and neopentyl glycol; aromatic alcohols such as alkylene oxide adducts of bisphenol A, such as polyoxypropylene-2,2-bis(4-hydroxyphenyl)propane and polyoxyethylene-2,2-bis(4-hydroxyphenyl)propane; and hydrogenated bisphenol A or its alkylene oxide (having 2 to 4 carbon atoms) adduct (average number of added moles: 1 to 16).

[0095] An aliphatic polybasic acid may be added to the polyester resin to improve fluidity. Examples of the aliphatic polybasic acid include saturated aliphatic dicarboxylic acids or anhydrides thereof, such as succinic acid, succinic anhydride, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, and 1,4-cyclohexanedicarboxylic acid; unsaturated aliphatic dicarboxylic acids or anhydrides thereof, such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, citraconic acid, and citraconic anhydride; and tri- or higher functional aliphatic carboxylic acids, such as 1,2,3,4-butanetetracarboxylic acid.

[0096] The polyester resin may be either a synthetic resin or a commercially available product, such as MD1335, MD1480, and other Vylonal series resins (manufactured by Toyobo Co., Ltd.), or KT-0507, KT-8904, KT-8701, KT-9204, and other Elitel series resins (manufactured by Unitika Ltd.).

[0097] The urethane resin is a resin having a urethane bond. In addition to the urethane bond, the urethane resin may be a polyether urethane resin having an ether bond in the main chain, a polyester urethane resin having an ester bond in the main chain, or a polycarbonate urethane resin having a carbonate bond in the main chain.

[0098] The urethane resin may be synthesized appropriately or may be a commercially available product, such as Superflex 300, Superflex 420, Superflex 460, Superflex 460S, Superflex 470, Superflex 740 (glass transition temperature: −34° C.), Superflex 150HS (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), DAOTAN TW6493 / 35WA (manufactured by Daicel-Allnex Corporation), Takelac W-6061 (manufactured by Mitsui Chemicals, Inc.), UW-1701F (manufactured by Ube Industries, Ltd.), Parmarin UA-150, or U-coat DA-200 (manufactured by Sanyo Chemical Industries, Ltd.).

[0099] In the decolorizable ink, the resin is preferably contained as emulsion particles. The shape of the emulsion particles is not particularly limited, but they are usually spherical. The shape can be measured using a transmission electron microscope or a scanning electron microscope. The emulsion particles may have a single-layer structure or a multi-layer structure (e.g., a core-shell structure).

[0100] The average particle size of the emulsion particles is preferably 50 nm or more, more preferably 80 nm or more, and even more preferably 100 nm or more. The average particle size of the emulsion particles is preferably 500 nm or less, more preferably 350 nm or less, and even more preferably 300 nm or less. By adjusting the average particle size of the emulsion particles to fall within the above range, it becomes easier to incorporate emulsion particles at a high concentration while maintaining the viscosity of the erasable ink within an appropriate range. The average particle size of the emulsion particles may be determined by the cumulant average particle size measured by dynamic light scattering, as shown in the examples below.

[0101] The content of the resin (preferably emulsion particles) in the erasable ink is, for example, 10% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, and for example, 35% by mass or less, preferably 30% by mass or less, more preferably 25% by mass or less. By adjusting the resin content within the above range, the viscosity of the erasable ink can be maintained within an appropriate range, while the effects of the present invention can be further enhanced.

[0102] The water and water-soluble organic solvent act as diluents to adjust the viscosity of the erasable ink. The total content of water and water-soluble organic solvent in the erasable ink can be set according to the desired viscosity of the erasable ink and is not particularly limited, but is, for example, 40 to 90 mass %, preferably 50 to 88 mass %, and more preferably 55 to 85 mass %.

[0103] Examples of the water-soluble organic solvent include: Lower alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, and tert-butyl alcohol; Glycols such as propylene glycol, 1,3 propanediol, glycerin, dipropylene glycol, tripropylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol; ethers of monoethylene glycol such as monoethylene glycol monomethyl ether, monoethylene glycol monoethyl ether, monoethylene glycol monopropyl ether, monoethylene glycol monoisopropyl ether, monoethylene glycol monobutyl ether, and monoethylene glycol monoisobutyl ether; ethers of monopropylene glycol such as monopropylene glycol monomethyl ether, monopropylene glycol monoethyl ether, monopropylene glycol monopropyl ether, monopropylene glycol monoisopropyl ether, monopropylene glycol monobutyl ether, and monopropylene glycol monoisobutyl ether; ethers of diethylene glycol such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, and diethylene glycol monoisobutyl ether; ethers of dipropylene glycol such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoisopropyl ether, dipropylene glycol monobutyl ether, and dipropylene glycol monoisobutyl ether; ethers of polyethylene glycol, such as monomethyl ether of polyethylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monoethyl ether of polyethylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monopropyl ether of polyethylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monoisopropyl ether of polyethylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monobutyl ether of polyethylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), and monoisobutyl ether of polyethylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4); ethers of polypropylene glycol, such as monomethyl ether of polypropylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monoethyl ether of polypropylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monopropyl ether of polypropylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monoisopropyl ether of polypropylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), monobutyl ether of polypropylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4), and monoisobutyl ether of polypropylene glycol (number of moles of EO added=2 to 10, preferably 2 to 4); Heterocycles such as 2-pyrrolidone and N-methyl-2-pyrrolidone; Examples include ketones such as acetone and methyl ethyl ketone.

[0104] The inclusion of a water-soluble organic solvent in the erasable ink can improve the ink's moisture retention and compatibility with the resin. The water-soluble organic solvent may be used alone or in combination of two or more. The content of the water-soluble organic solvent is preferably 10 to 55 parts by mass, more preferably 15 to 45 parts by mass, per 100 parts by mass of water contained in the erasable ink.

[0105] In particular, from the viewpoint of further enhancing moisture retention, water-soluble organic solvents having a boiling point of 150°C or higher are preferred, water-soluble organic solvents having a boiling point of 180°C or higher are more preferred, and water-soluble organic solvents having a boiling point of 200°C or higher are even more preferred. Examples of water-soluble organic solvents having a boiling point of 150°C or higher include propylene glycol, diethylene glycol, triethylene glycol, and glycerin. The content of the water-soluble organic solvent, which enhances moisture retention, is preferably 10 to 50 parts by mass, and more preferably 15 to 40 parts by mass, per 100 parts by mass of water contained in the erasable ink.

[0106] Furthermore, from the viewpoint of further improving compatibility with the resin, a water-soluble organic solvent having a hydrophobic group and a hydroxyl group is preferred, and among these, at least one selected from the group consisting of diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, monobutyl ether of polyethylene glycol (EO addition mole number = 2 to 4) (particularly triethylene glycol monobutyl ether), and monomethyl ether of polypropylene glycol (EO addition mole number = 2 to 10, preferably 2 to 4) (particularly tripropylene glycol monomethyl ether) is preferred. The content of the water-soluble organic solvent, which further improves compatibility, is preferably 1 to 15 parts by mass, more preferably 2 to 8 parts by mass, per 100 parts by mass of water contained in the erasable ink.

[0107] The total content of the resin, water, and water-soluble organic solvent in the erasable ink is not particularly limited, but is, for example, 70% by mass or more, preferably 85% by mass or more, and more preferably 95% by mass or more. The total content may be 100% by mass or 99.5% by mass or less.

[0108] The erasable ink may further contain a crosslinking agent. It is believed that the use of a crosslinking agent forms a crosslinked structure through interaction with components contained in the erasable ink, such as a resin, or through a chemical reaction, thereby forming a tough coating film, and that this further improves the wet rub fastness and washing fastness of the resulting transfer.

[0109] Examples of the crosslinking agent include an isocyanate compound, an epoxy compound, a melamine compound, a metal chelate compound, an aziridine compound, a mercapto compound, and an oxazoline compound, and preferably an oxazoline compound. The crosslinking agent may be used alone or in combination of two or more.

[0110] The oxazoline compound as the crosslinking agent means a compound having two or more oxazoline groups in the molecule. Examples of the oxazoline compound include 2,2'-bis(2-oxazoline), 2,2'-methylene-bis(2-oxazoline), 2,2'-ethylene-bis(2-oxazoline), 2,2'-trimethylene-bis(2-oxazoline), 2,2'-tetramethylene-bis(2-oxazoline), 2,2'-hexamethylene-bis(2-oxazoline), 2,2'-octamethylene-bis(2-oxazoline), 2,2'-ethylene-bis(4 ,4'-dimethyl-2-oxazoline), 2,2'-p-phenylene-bis(2-oxazoline), 2,2'-m-phenylene-bis(2-oxazoline), 2,2'-m-phenylene-bis(4,4'-dimethyl-2-oxazoline), bis(2-oxazolinylcyclohexane) sulfide, bis(2-oxazolinylnorbornane) sulfide, oxazoline group-containing polymers, etc., but are not limited to these examples.

[0111] Among the above oxazoline compounds, water-soluble oxazoline compounds are preferred from the viewpoint of excellent crosslinking performance, and oxazoline group-containing polymers are also preferred. The oxazoline group-containing polymer can be produced by a conventionally known production method. For example, a method of polymerizing a monomer component containing one or more addition-polymerizable oxazolines, or an addition-polymerizable oxazoline and a monomer copolymerizable with the addition-polymerizable oxazoline, is exemplified. The copolymerizable monomer is preferably a monomer copolymerizable with the addition-polymerizable oxazoline, but does not have a functional group reactive with the oxazoline group. Examples of the above monomer component include a monomer that does not have a functional group reactive with the oxazoline group. Examples of the copolymerizable monomer include (meth)acrylic monomers such as alkyl (meth)acrylates; styrene-based monomers such as styrene, α-methylstyrene, and chloromethylstyrene; vinyl-based monomers such as vinyl acetate, vinyl chloride, and vinyl benzoate; acrylonitrile; (meth)acrylamide-based monomers such as acrylamide; and olefin-based monomers such as ethylene and propylene.

[0112] Examples of the addition-polymerizable oxazoline include compounds having a polymerizable unsaturated group and an oxazoline group in the molecule, such as 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, and 2-isopropenyl-5-ethyl-2-oxazoline.

[0113] Among the oxazoline group-containing polymers, water-soluble oxazoline group-containing polymers are preferred, and can be produced by the same method as the above-mentioned method for producing the oxazoline group-containing polymer. Examples of the water-soluble oxazoline group-containing polymer include polymers having an acrylic resin or the like as a main chain and containing oxazoline groups in side chains.

[0114] Commercially available oxazoline group-containing polymers can also be used. Examples include water-soluble polymers such as Epocross WS-500 and Epocross WS-700, manufactured by Nippon Shokubai Co., Ltd., and emulsion polymers such as Epocross K-2010, Epocross K-2020, and Epocross K-2030. Among these, the water-soluble polymers Epocross WS-500 and Epocross WS-700 are preferred.

[0115] The content of the crosslinking agent (preferably, an oxazoline compound) is not particularly limited, but is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 8 parts by mass, and even more preferably 0.2 to 5 parts by mass, relative to 100 parts by mass of the resin.

[0116] The erasable ink may further contain a surfactant. The use of a surfactant makes it possible to adjust the surface tension to a level suitable for inkjet ejection. The content of the surfactant is not particularly limited, but is preferably 0.01 to 2% by mass, and more preferably 0.1 to 1% by mass, relative to 100% by mass of the erasable ink.

[0117] As the surfactant, for example, an acetylene glycol surfactant, a silicone surfactant, a fluorine surfactant, etc. are preferably used. Among these, a silicone surfactant is more preferable, and a polyether-modified silicone surfactant is even more preferable.

[0118] The erasable ink may contain other components in addition to the components described above, provided that the object of the present invention is not impaired. For example, the erasable ink may contain appropriate amounts of additives such as dispersants, leveling agents, UV absorbers, UV stabilizers, thickeners, wetting agents, plasticizers, stabilizers, defoamers, pigments, dyes, antioxidants, crosslinking accelerators, pH adjusters, preservatives, chain transfer agents, and chelating agents.

[0119] When the other components are added, their content is not particularly limited, but is preferably 2% by mass or less, more preferably 1% by mass or less, relative to 100% by mass of the erasable ink. In order to exert the effect of addition, their content is preferably 0.01% by mass or more, more preferably 0.05% by mass or more.

[0120] The erasable ink may be an inkjet ink containing an erasable colorant, a color developer, and a resin, the resin having a glass transition temperature of 30° C. or higher and a weight average molecular weight of 10,000 to 700,000. Such an inkjet ink is also encompassed within one embodiment of the present invention.

[0121] <1-3. Drying process> The drying step is a step of drying the erasable ink by heating to form a transparent coating film of the erasable ink. The drying step is a step of evaporating some or all of the components (i.e., solvent) excluding the solid content of the non-erasable ink and the erasable ink printed on the non-erasable ink. Furthermore, the erasable colorant that was colored in the erasable ink application step can be erased by heating. This forms a transparent coating film of the erasable ink.

[0122] The drying device (also referred to as a heating device) is not particularly limited, and examples thereof include contact-type heating devices such as platen heaters and rubber heaters, and non-contact heating devices such as hot air heaters, infrared heaters, and halogen heaters. From the viewpoint of achieving uniform drying, the drying process is preferably performed using a contact-type heating device, and more preferably using a platen heater. Furthermore, from the viewpoint of suppressing temperature unevenness within the coating film, it is preferable to use a non-contact heating device in addition to the contact-type heating device in the drying process. For example, the drying process may be performed using a non-contact heating device provided in the carriage unit in addition to the platen heater, or may be performed using a large non-contact heating device that covers the platen heater. For example, the non-erasable ink and the erasable ink can be dried by heating the recording medium from the back side using a platen heater. Additionally, the recording medium may be heated from the front side using a halogen heater provided in the carriage unit. This allows the ink coating film to be dried from both the front and back sides.

[0123] The amount of solvent evaporation can be adjusted by controlling the heating temperature, heating time, hot air temperature, air volume, etc. The heating temperature in the drying step is preferably 30°C or higher, more preferably 40°C or higher, even more preferably 50°C or higher, and particularly preferably 60°C or higher, from the viewpoint of shortening the heating time. Furthermore, the heating temperature in the drying step is preferably 180°C or lower, more preferably 170°C or lower, and even more preferably 160°C or lower, from the viewpoint of preventing deformation of the recording medium.

[0124] The heating time in the drying step is preferably 1 minute or longer, more preferably 2 minutes or longer, and even more preferably 3 minutes or longer from the viewpoint of sufficient evaporation of the solvent, and is preferably 20 minutes or shorter, more preferably 15 minutes or shorter, and even more preferably 10 minutes or shorter from the viewpoint of productivity.

[0125] The drying step may be carried out simultaneously with the erasable ink application step, or after the erasable ink application step, or both simultaneously with the erasable ink application step and after the erasable ink application step. By carrying out the drying step simultaneously with the erasable ink application step, the erasable ink coating film can be dried efficiently. When the drying step is carried out simultaneously with the erasable ink application step, it may be carried out continuously from the start to the end of the erasable ink application step, or may be carried out intermittently, but it is preferable to carry out the drying step continuously. Furthermore, by carrying out the drying step after the erasable ink application step, it becomes easier to visually confirm the ejection of the erasable ink.

[0126] The thickness of the erasable ink coating is not particularly limited, but is preferably 0.5 μm or more, more preferably 2 μm or more, even more preferably 5 μm or more or more than 5 μm, and particularly preferably 8 μm or more, in terms of film thickness after drying. By adjusting the erasable ink coating to the above thickness, the transferability and wet rub fastness of the resulting transferred product are improved. Furthermore, from the viewpoint of improving the texture of the resulting transferred product, the thickness of the erasable ink coating is preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less, and may be 50 μm or less.

[0127] 2. Method for producing transfer product A method for manufacturing a transferred object according to one embodiment of the present invention includes a step of bringing a recorded object having an image manufactured by the above-described method for manufacturing a recorded object into contact with a transferee material and applying pressure and heat to transfer the image to the transferee material. The method for manufacturing a transferred object may include a step of manufacturing a recorded object having an image by the above-described method for manufacturing a recorded object, and a step of bringing the recorded object into contact with a transferee material and applying pressure and heat to transfer the image to the transferee material.

[0128] The transferred material is obtained by transferring the image provided on the recorded material to a transfer-receiving material, and includes the transfer-receiving material and the image provided thereon. The transfer-receiving material may be fabric. When the transfer-receiving material is fabric, the transferred material is also called a printed material.

[0129] The fabric used is not particularly limited and includes all textile products such as cloth, textile, etc. Examples of the fabric include woven fabric, nonwoven fabric, knitted fabric, etc. The fibers constituting the fabric are also not particularly limited and include, for example, natural fibers, chemical fibers, or mixtures thereof.

[0130] Examples of natural fibers include silk, cotton, and wool. Examples of chemical fibers include synthetic fibers, regenerated fibers, and semi-synthetic fibers. Examples of synthetic fibers include polyester fibers, nylon fibers, acrylic fibers, polyurethane fibers, polyethylene fibers, polypropylene fibers, and vinylon fibers. Examples of regenerated fibers include rayon. Examples of semi-synthetic fibers include acetate and triacetate. Among these, fabrics made from cotton, polyester fibers, polypropylene fibers, nylon fibers, or mixtures thereof are preferred.

[0131] The transfer method is not particularly limited, and any conventionally known method can be used. For example, the transfer preferably includes a step of bringing the surface of the recorded matter on which the adhesive layer is formed into contact with a transfer-receiving material in a state where the surface faces the transfer-receiving material, and a step of peeling the recording medium from the transfer-receiving material.

[0132] Examples of methods for applying pressure and heat include a method in which the recorded material is closely attached to the transfer material using a press or a heated drum, and then heat and pressurize. The heating temperature during transfer is not particularly limited, but is preferably 80 to 200°C, and more preferably 100 to 180°C. The pressure during transfer is also not particularly limited, but is preferably 100 to 600 g / cm. 2 and more preferably 200 to 500 g / cm 2 From the viewpoint of further improving transferability, the contact time is preferably 1 second or more, more preferably 3 seconds or more. There is no particular upper limit to the contact time, but from the viewpoint of productivity, it is preferably 1 minute or less, and more preferably 30 seconds or less.

[0133] The recording medium is peeled off from the transfer material to obtain a transfer product. Note that, from the viewpoint of reducing ink remaining on the recording medium, it is preferable to peel off the recording medium after the temperature of the transfer material has reached 60°C or less (particularly 40°C or less).

[0134] The resulting transferred product may be further heated and pressurized using a press or a heated drum. By subjecting the resulting transferred product to additional heating and pressurization treatment, the ink and the transfer material are more firmly bonded to each other, and wet rubbing resistance is further improved. The additional heating temperature is not particularly limited, but is preferably 80 to 200°C, and more preferably 100 to 180°C. The pressure in the additional pressurization is also not particularly limited, but is preferably 100 to 600 g / cm. 2 and more preferably 200 to 500 g / cm 2 The additional heating and pressurizing time is not particularly limited, but is preferably 1 second to 1 minute, and more preferably 3 seconds to 30 seconds.

[0135] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0136] An embodiment of the present invention may include the following features. <1> A method for producing a recorded matter, comprising: a non-erasable ink applying step of applying a non-erasable ink containing a non-erasable colorant to a recording medium by an inkjet method; an erasable ink applying step of applying an erasable ink containing an erasable colorant and a color developer onto a coating film of the non-erasable ink by an inkjet method; and a drying step of drying the erasable ink by heating to form a transparent coating film of the erasable ink. <2> The decolorizable colorant is a decolorizable colorant that is decolorized by heating. <1> A method for producing the recorded matter described above. <3> The decolorizable colorant is a leuco dye. <1> or <2> A method for producing the recorded matter described above. <4> The non-bleachable colorant is a white colorant. <1> ~ <3> A method for producing a recorded matter according to any one of the above. <5> The recording medium is a film. <1> ~ <4> A method for producing a recorded matter according to any one of the above. <6> The heating temperature in the drying step is 30°C or higher. <1> ~ <5> A method for producing a recorded matter according to any one of the above. <7> The erasable ink contains a resin, an aqueous organic solvent, and water. <1> ~ <6> A method for producing a recorded matter according to any one of the above. <8> The resin is one or more resins selected from the group consisting of acrylic resins and polyester resins. <7> A method for producing the recorded matter described above. <9> The glass transition temperature of the resin is 30°C or less. <7> or <8> A method for producing the recorded matter described above. <10> The weight average molecular weight of the resin is 10,000 to 700,000. <7> ~ <9> A method for producing a recorded matter according to any one of the above. <11> <1> ~ <10> A method for manufacturing a transferred material, comprising a step of contacting a recorded material having an image manufactured by the method for manufacturing a recorded material described in any one of the above with a transfer material, and applying pressure and heat to transfer the image to the transfer material. <12> The transfer material is a fabric. <11> A method for producing the transcript described in <13> An inkjet ink comprising a decolorizable colorant, a color developer, and a resin, wherein the resin has a glass transition temperature of 30° C. or lower and a weight average molecular weight of 10,000 to 700,000. [Example]

[0137] An example of the present invention will be described below. Unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass."

[0138] [Methods for measuring physical properties] (Measurement of Tg of emulsion particles) The glass transition temperature (Tg) of the emulsion particles was measured by differential scanning calorimetry (DSC) under the following measurement conditions.

[0139] Measuring equipment: DSC 3500 (NETZSCH) Sample container: Aluminum airtight container Sample weight: 10mg±2mg Measurement method: Two cycles of heating from -50°C to 150°C were performed in a N2 atmosphere. The heating and cooling rates were 10°C / min, and the holding times at -50°C and 150°C were 5 minutes. Using the analysis software Proteus Analysis, the glass transition temperature was analyzed from the DSC curve chart during the second heating cycle, and the midpoint glass transition temperature was used.

[0140] (Measurement of the average particle size of emulsion particles) The average particle size of the emulsion particles was measured using the emulsion obtained in each production example as a measurement sample with a particle size distribution analyzer (Otsuka Electronics Co., Ltd., product number: FPAR-1000) by dynamic light scattering, and was determined using cumulant analysis.

[0141] (Measurement of weight-average molecular weight of emulsion particles) The weight average molecular weight (Mw) of the emulsion particles was measured by GPC (gel permeation chromatography) under the following measurement conditions.

[0142] Measuring equipment: HLC-8320GPC (Tosoh Corporation) Molecular weight column: TSK-GEL SuperMultiporeHZ (Tosoh Corporation) Eluent: tetrahydrofuran (THF) Standard material for calibration curve: Polystyrene (manufactured by Tosoh Corporation) Measurement method: The material to be measured was dissolved in THF so that the solid content was approximately 0.2% by mass, and the resultant was filtered to measure the molecular weight. The flow rate of the liquid delivery pump was 0.35 mL / min.

[0143] [Ink production] <Production of colorant powder> First, we will explain the manufacturing method of the pigment paste (pigment dispersion) containing the leuco dye. The leuco dye S-205 (manufactured by Yamada Chemical Co., Ltd.) and the color developer bisphenol A were heated and melted, cooled, and then pulverized in a dry ball mill to produce a black colorant powder.

[0144] <Production of Black Pigment Dispersion> 15 parts of colorant powder, 3 parts of Joncryl 678 (BASF) as a dispersant, and 82 parts of deionized water were mixed, and 50% by volume of zirconia beads with a particle size of 0.5 mm was added. In other words, the zirconia beads were added so that they accounted for 50% by volume of a 100% volume mixture of these materials including the zirconia beads. These materials were dispersed using a bead mill and filtered through a 1 μm pore size filter, MCP-1-C10S (Advantec), to obtain a black pigment dispersion.

[0145] <Production of White Pigment Dispersion> Five parts of Discoat N-14 (Dai-ichi Kogyo Seiyaku Co., Ltd.) as a dispersant, six parts of propylene glycol, 70 parts of deionized water, and 100 parts of titanium dioxide CR-95 (Ishihara Sangyo Kaisha, Ltd.) as a white pigment were mixed, and 0.5 mm particle size zirconia beads were added to the mixture at a volume ratio of 50%. These materials were dispersed using a bead mill and filtered through a 1 μm pore size filter MCP-1-C10S (Advantec Co., Ltd.) to obtain a white pigment dispersion containing 55% pigment.

[0146] <Production of emulsion 1> An acrylic resin emulsion (hereinafter referred to as emulsion 1) was obtained by emulsion polymerization. The solid content of emulsion 1 was 55%, and the Tg of the emulsion particles contained in emulsion 1 was 10°C, the average particle diameter was 200 nm, and the weight average molecular weight was 300,000.

[0147] <Production of emulsion 2> Eucoat DA-200 (polyether urethane emulsion) (hereinafter referred to as emulsion 2) manufactured by Sanyo Chemical Industries, Ltd. was prepared. The solid content of emulsion 2 was 38%, and the Tg of the emulsion particles contained in emulsion 2 was -70°C.

[0148] <Production of emulsion 3> An acrylic styrene-based resin emulsion (hereinafter referred to as emulsion 3) was obtained by emulsion polymerization. The solid content of emulsion 3 was 50%, and the Tg of the emulsion particles contained in emulsion 3 was −21° C., the average particle diameter was 200 nm, and the weight average molecular weight was 1,100,000.

[0149] <Preparation of erasable ink 1> Decolorizable ink 1 was prepared by mixing 0.5 parts of the black pigment dispersion, 40 parts of emulsion 1 (20 parts as emulsion particles), 15 parts of propylene glycol, 2 parts of diethylene glycol monobutyl ether, 0.5 parts of KF-6011 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a surfactant, and 42 parts of deionized water.

[0150] <Preparation of erasable ink 2> Decolorizable ink 2 was prepared by mixing 0.5 parts of the black pigment dispersion, 50 parts of emulsion 2 (19 parts as emulsion particles), 15 parts of propylene glycol, 2 parts of diethylene glycol monobutyl ether, 0.5 parts of KF-6011 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a surfactant, and 32 parts of deionized water.

[0151] <Preparation of colorless ink> A colorless ink was prepared by mixing 40 parts of emulsion 1 (20 parts as emulsion particles), 15 parts of propylene glycol, 2 parts of diethylene glycol monobutyl ether, 0.5 parts of KF-6011 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a surfactant, and 41.5 parts of deionized water.

[0152] <Preparation of White Ink (Non-erasable Ink)> A non-erasable white ink was prepared by mixing 30 parts of emulsion 3 (15 parts as emulsion particles), 23 parts of the white pigment dispersion, 1.2 parts (0.3 parts as solids) of Epocross WS-700 (manufactured by Nippon Shokubai, solids content 25%), 2 parts of diethylene glycol monobutyl ether, 15 parts of triethylene glycol, 0.3 parts of KF-6011 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a surfactant, and 28.5 parts of deionized water.

[0153] [Evaluation of Examples] <Ink visibility> Erasable ink 1 and white ink were filled into an inkjet ejection device (Mastermind MMP-TX13). A 10 cm x 10 cm solid pattern was printed on a PET transfer film for DTF printing using the white ink, and after drying in an oven at 50°C for 2 minutes, a test pattern using erasable ink 1 was printed on the printed material. The printed test pattern was evaluated for visual visibility. The combination of erasable ink 2 and white ink was also evaluated in the same way.

[0154] <Ink erasability> Using the inkjet ejection device, a 10 cm x 10 cm solid pattern was printed with white ink on a PET transfer film for DTF printing, and then a 10 cm x 10 cm solid pattern was printed on top of that with erasable ink 1. After printing, the print was dried by heating at 140°C for 10 minutes in an oven dryer (ETTAS OF-450B). The dried print was visually inspected to evaluate whether the print with erasable ink 1 had been erased. The combination of erasable ink 2 and white ink was also evaluated in the same manner.

[0155] [Evaluation of Comparative Examples] The visibility of the ink was evaluated using colorless ink instead of the erasable ink. The comparative example was not evaluated for erasability because the colorless ink was used and the ink was erased immediately after printing.

[0156] [Evaluation results] In the evaluation of the visibility of the ink, the test patterns could be visually observed for the erasable inks 1 and 2 of the examples. In contrast, the test patterns could not be visually observed for the colorless ink of the comparative example. Furthermore, in the evaluation of the ink's erasability, it was confirmed that the printed matter was erased after drying in the examples. From the above, it can be seen that the ink of the examples containing an erasable colorant and a color developer allows for visual confirmation of the ejection properties, and is also erased in the subsequent drying process, making it possible to form a transparent coating film. [Industrial Applicability]

[0157] One aspect of the present invention can be used, for example, in the production of a transfer film used for transfer onto a transfer-receiving material, and in the production of a transfer product.

Claims

1. a non-erasable ink applying step of applying a non-erasable ink containing a non-erasable colorant to a recording medium by an inkjet method; an erasable ink applying step of applying an erasable ink containing an erasable colorant and a color developer onto the coating film of the non-erasable ink by an inkjet method; a drying step of drying the erasable ink by heating to form a transparent coating film of the erasable ink.

2. The method for producing a recorded matter according to claim 1 , wherein the decolorable coloring material is a decolorable coloring material that is decolorized by heating.

3. The method for producing a recorded matter according to claim 1 , wherein the decolorable coloring material is a leuco dye.

4. The method for producing a recorded matter according to claim 1 , wherein the non-bleachable coloring material is a white coloring material.

5. The method for producing a recorded matter according to claim 1 , wherein the recording medium is a film.

6. The method for producing a recorded matter according to claim 1 , wherein the heating temperature in the drying step is 30° C. or higher.

7. The method for producing a recorded matter according to claim 1 , wherein the erasable ink contains a resin, an aqueous organic solvent, and water.

8. The method for producing a recorded matter according to claim 7 , wherein the resin is one or more resins selected from the group consisting of acrylic resins and polyester resins.

9. The method for producing a recorded matter according to claim 7, wherein the resin has a glass transition temperature of 30°C or lower.

10. 8. The method for producing a recorded matter according to claim 7, wherein the weight average molecular weight of the resin is 10,000 to 700,000.

11. A method for manufacturing a transferred material, comprising a step of contacting a recorded material having an image manufactured by the method for manufacturing a recorded material according to any one of claims 1 to 10 with a transfer material, and applying pressure and heat to transfer the image to the transfer material.

12. The method for producing a transfer product according to claim 11 , wherein the transfer material is a fabric.

13. The ink contains a decolorizable color material, a color developer, and a resin, The resin has a glass transition temperature of 30°C or less, The weight average molecular weight of the resin is 10,000 to 700,000.