JP7469975B2 - Dye-sublimation inkjet textile transfer paper and its manufacturing method - Google Patents

Description

This disclosure relates to dye-sublimation inkjet textile transfer paper and its manufacturing method.

There are various transfer printing methods, such as melting transfer printing, rubber print transfer printing, and dye-sublimation transfer printing, but dye-sublimation transfer printing with inkjet recording is widely used because it can handle small lot sizes and can print clear images at high speeds. Dye-sublimation transfer printing has the advantage of being able to print clear patterns with high resolution, which is difficult to achieve with other transfer methods, and so its use has been expanded to include elastic recipients such as clothing and fabrics made primarily of synthetic fibers. In order to improve the transfer efficiency for elastic recipients with uneven surfaces, it was necessary to improve the adhesion between the dye-sublimation paper and the recipient.

Patent Document 1 describes a dye-sublimation inkjet printing transfer paper in which a second coating layer containing a specific ratio of polyolefin emulsion and hydroxylated cellulose is provided on a first coating layer containing inorganic particles and a binder. Patent Document 2 describes an inkjet recording sheet in which an ink-receiving layer containing a specific polymer compound is provided on a support to achieve high visual whiteness and good color reproducibility. Patent Document 3 describes a printing paper in which a paste layer containing a water-soluble polyester binder and a natural paste is provided on the surface of the base paper.

JP 2019-181805 A Japanese Patent Application Laid-Open No. 11-058932 JP 2016-104917 A

The dye-sublimation inkjet textile transfer paper described in Patent Document 1 has a structure in which an adhesive second coating layer is laminated on a first coating layer containing a receptive layer paint, so if the coating weight of the second coating layer is increased to improve adhesion to the transferee, the function of the first coating layer is reduced, and ink receptivity and transferability are reduced. In addition, in order to improve the ink receptivity and transferability of the first coating layer, it is necessary to reduce the coating weight of the second coating layer, but in this case, adhesion to the transferee is reduced. In other words, with the structure of the dye-sublimation inkjet textile transfer paper described in Patent Document 1, it was difficult to improve all of the adhesion to the transferee, ink receptivity, and transferability. In addition, the dye-sublimation inkjet textile transfer paper described in Patent Document 1 requires coating the first coating layer and the second coating layer in separate processes, making the manufacturing process complicated and leaving room for improvement.

The inkjet recording sheet described in Patent Document 2 has physical properties required as paper that are significantly different from those of textile transfer paper, making it difficult to convert it into the dye-sublimation inkjet textile transfer paper of the present invention.

The printing paper described in Patent Document 3 is also used in a transfer method that involves steaming and water washing processes, and the natural adhesive has weak adhesion to the transfer target, making it difficult to use it in the dye-sublimation inkjet printing transfer paper of the present invention.

The present invention aims to provide a dye-sublimation inkjet textile transfer paper that has excellent adhesion to the substrate, good ink receptivity and transferability, and few coating defects.

The dye-sublimation inkjet textile transfer paper according to the present invention has an ink-receiving layer formed on one side of a base paper, and the ink-receiving layer contains an adhesive, a surfactant, and a water-soluble polymer, the adhesive being a polyolefin resin, the surfactant having an HLB value of 10 to 20, and the water-soluble polymer being one or more of carboxymethyl cellulose, hydroxylated cellulose, and polyvinyl alcohol.

The method for producing the dye-sublimation inkjet textile transfer paper according to the present invention is characterized in that an adhesive and a surfactant are mixed, and then a water-soluble polymer is further mixed into the mixture to prepare an ink-receiving layer coating liquid, and the prepared ink-receiving layer coating liquid is applied to one side of a base paper, the adhesive being a polyolefin resin, the surfactant having an HLB value of 10 to 20, and the water-soluble polymer being carboxymethylcellulose.

The present invention provides dye-sublimation inkjet textile transfer paper that has excellent adhesion to the substrate, good ink receptivity and transferability, and few coating defects.

The dye-sublimation inkjet textile transfer paper of the present invention has an ink-receiving layer formed on one side of a base paper. The base paper and the ink-receiving layer are described in detail below.

(Base paper: Raw pulp)
The raw pulp constituting the base paper may be, for example, virgin pulp, recycled pulp, or a combination of these pulps.

Examples of virgin pulp include chemical pulps such as bleached hardwood kraft pulp (LBKP), bleached softwood kraft pulp (NBKP), unbleached hardwood kraft pulp (LUKP), unbleached softwood kraft pulp (NUKP), semi-bleached hardwood kraft pulp (LSBKP), semi-bleached softwood kraft pulp (NSBKP), hardwood sulfite pulp, and softwood sulfite pulp; and mechanical pulps (MP) such as stone ground pulp (SGP), pressed stone ground pulp (TGP), chemi-ground pulp (CGP), groundwood pulp (GP), and thermomechanical pulp (TMP), which may be used alone or in combination.

Examples of waste paper pulp that can be used include disintegrated waste paper pulp, disintegrated and deinked waste paper pulp (DIP), and disintegrated, deinked and bleached waste paper pulp, which are produced from, for example, brown waste paper, kraft envelope waste paper, magazine waste paper, newspaper waste paper, flyer waste paper, office waste paper, cardboard waste paper, white waste paper, Kent waste paper, imitation waste paper, and land tax waste paper, and can be used alone or in combination.

(Base paper: Additives)
Additives may be added to the base paper, if necessary.

Additives that can be used alone or in combination include, for example, fillers, sizing agents, paper quality improvers, coagulants, defoamers, fluorescent whitening agents, aluminum sulfate, retention improvers, drainage improvers, dry strength enhancers, wet strength enhancers, coloring dyes, coloring pigments, and water-resistant agents.

(Base paper: Undercoat layer)
If necessary, the base paper may be provided with an undercoat layer mainly composed of a water-soluble polymer.

As the water-soluble polymer, for example, a natural polymer system can be used. As the natural polymer system, for example, enzymatically decomposed starch, oxidized starch, hydroxyethylated starch, cationic starch, urea phosphate starch, modified oxidized starch, etc., which are obtained by modifying raw starch such as corn, wheat, tapioca, potato, etc. by various methods, carboxymethyl cellulose (hereinafter also referred to as "CMC"), carboxyethyl cellulose (CEC), etc., can be used alone or in combination. In addition, the undercoat layer can contain additives such as sizing agents, water-resistant agents, coloring dyes, coloring pigments, defoamers, fluorescent whitening agents, etc.

(Base paper: EST sizing degree)
The base paper used has a time (hereinafter also referred to as EST sizing degree) of 0.01 to 3.00 seconds for the ultrasonic transmission intensity of the initial water absorption property of the base paper to reach 100%, as measured by a surface/sizing degree tester (EST12, manufactured by emtec). The base paper used has an EST sizing degree of 0.50 to 2.00 seconds, more preferably 0.80 to 1.80 seconds. The EST sizing degree measured by a surface/sizing degree tester is a parameter that indicates the permeability of the ink receiving layer paint into the base paper immediately after the ink receiving layer paint is applied. If the EST sizing degree is less than 0.01 seconds, the ink receiving layer paint will excessively permeate into the base paper, causing fine defects in the ink receiving layer, which may slightly reduce image reproducibility. On the other hand, if the EST sizing degree exceeds 3.00 seconds, the ink receiving layer paint will not easily permeate into the base paper, which may lead to a deterioration in the adhesion between the ink receiving layer and the base paper, which may slightly reduce image reproducibility. Therefore, in order to improve image reproducibility, it is preferable to use a base paper having an EST sizing degree in the range of 0.01 to 3.00 seconds. The EST sizing degree can be adjusted, for example, by combining the type and amount of additives such as sizing agents of the base paper, the coating amount of the undercoat layer, and the type and amount of additives.

(Underlayer)
In the dye-sublimation inkjet textile printing transfer paper, an underlayer containing carboxymethyl cellulose or the like may be formed between the dye-sublimation textile printing ink receiving layer and the base paper. The formation of the underlayer improves the compatibility of the wet paint immediately after application of the mixed paint, and therefore has the effect of making it easier to obtain a continuous coating without pinholes with a smaller amount of coating.

In addition to CMC, the underlayer coating material for forming the underlayer may contain ingredients such as starch derivatives such as starch, oxidized starch, cationized starch, etherified starch, and phosphated starch, cellulose derivatives such as hydroxymethyl cellulose, hydroxyethyl cellulose, and cellulose sulfate, polyvinyl alcohol (hereinafter also referred to as "PVA") with various degrees of saponification and various PVA derivatives such as its silanol-modified, carboxylated, and cationized products, water-soluble natural polymer compounds such as casein, gelatin, modified gelatin, and soy protein, and water-soluble synthetic polymer compounds such as polyvinylpyrrolidone, sodium polyacrylate, styrene-maleic anhydride copolymer sodium salt, and sodium polystyrene sulfonate, and there are no particular limitations as long as the effect of providing the underlayer is not impaired.

The undercoat paint may be the same as the ink-receiving layer paint. In this case, a smaller coating amount than a single application of the ink-receiving layer paint can be used to adequately prevent coating defects, resulting in excellent coating suitability.

When an underlayer is formed, the coating amount (after drying) of the underlayer coating is 3.0 g/ ^m2 or less. If the coating amount (after drying) of the underlayer coating exceeds 3.0 g/ ^m2 , the air permeability becomes too high, blisters occur during textile transfer, and reproducibility of the transferred image decreases at the location where blisters occur.

(Ink Receiving Layer)
The ink receiving layer is made of an ink receiving layer paint containing an adhesive, a water-soluble polymer, and a surfactant.

(Adhesive)
As the adhesive, a polyolefin resin can be suitably used. The polyolefin resin melts due to heat during the textile transfer and exhibits adhesion and plasticity to the transferee. When the ink receiving layer contains a polyolefin resin, the adhesion between the dye-sublimation inkjet textile transfer paper and the transferee during the textile transfer is improved, and the misalignment of the transferred image to the transferee can be prevented. In this specification, the polyolefin resin is a polymer obtained by polymerizing olefins such as polyethylene and polypropylene, and includes not only homopolymers of one type of olefin, but also copolymers obtained by copolymerizing two or more types of olefins having different carbon chain lengths, and copolymers obtained by copolymerizing an olefin with an acrylic monomer such as acrylic acid or methacrylic acid. From the viewpoint of adhesion, it is preferable to use a polyolefin resin having an average weight average molecular weight of about 30,000 to 40,000. In addition, it is preferable to use a polyolefin resin dispersed in water as the adhesive, since the adhesive is applied as a water-based ink receiving layer paint.

(Water-soluble polymer)
The water-soluble polymer has a function of capturing and absorbing the dye-sublimation printing ink and a function as a binder. The ink-receiving layer contains at least one of carboxymethyl cellulose (CMC), hydroxylated cellulose, and polyvinyl alcohol (PVA) as the water-soluble polymer. Examples of the hydroxylated cellulose include hydroxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose. As other water-soluble polymers, at least one selected from starch derivatives such as oxidized starch, cationic starch, etherified starch, and phosphated starch, cellulose derivatives such as cellulose sulfate and their silanol-modified and carboxylated derivatives, water-soluble natural polymer compounds such as casein, gelatin, modified gelatin, and soybean protein, and water-soluble synthetic polymer compounds such as polyvinylpyrrolidone, sodium polyacrylate, styrene-maleic anhydride copolymer sodium salt, and sodium polystyrene sulfonate can be used in combination. From the viewpoint of the ink receptivity required for the ink-jet printing transfer paper, it is preferable to use carboxymethyl cellulose.

The content of the water-soluble polymer in the ink receiving layer is preferably 20 to 50 parts by mass per 100 parts by mass of the adhesive. If the content of the water-soluble polymer is less than 20 parts by mass per 100 parts by mass of the adhesive, the ink receptivity may be insufficient, and if it exceeds 50 parts by mass, the adhesiveness may be insufficient. In other words, by having the content of the water-soluble polymer be 20 to 50 parts by mass per 100 parts by mass of the adhesive, it is possible to achieve both the ink receptivity required for the inkjet textile transfer paper and the adhesiveness required to prevent transfer misalignment. It is more preferable that the content of the water-soluble polymer in the ink receiving layer be 25 to 45 parts by mass per 100 parts by mass of the adhesive.

(Surfactant)
When preparing the ink-receiving layer coating, the adhesive and the water-soluble polymer are mixed together, causing the adhesive and the water-soluble polymer to aggregate. If the ink-receiving layer coating contains aggregates, clogging of the screen (filter) of the coating device for the ink-receiving layer coating occurs, making it difficult to stably produce the dye-sublimation inkjet textile transfer paper. In addition, if the ink-receiving layer coating contains aggregates, coating unevenness of the ink-receiving layer coating may occur, and defects called streaks or scratches may occur in the ink-receiving layer after drying. Reducing the amount of adhesive reduces aggregation, but also reduces the adhesion of the dye-sublimation inkjet textile transfer paper.

Therefore, a surfactant is blended into the ink receiving layer (ink receiving layer paint) according to this embodiment. A compound with an HLB (hydrophilic-lipophilic balance) value of 10 to 20 can be suitably used as the surfactant. By blending a surfactant with an HLB value of 10 to 20 into the ink receiving layer paint, it is possible to suppress aggregation between the water-soluble polymer and the adhesive. The HLB value of the surfactant is preferably 13 to 20, and more preferably 16 to 20. By using a surfactant with a higher HLB value, it is possible to improve the dispersibility in water of the adhesive made of polyolefin resin.

The type of surfactant is not particularly limited, and any of nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants can be used, but among them, nonionic surfactants are preferred because they have an excellent effect of suppressing aggregation between the water-soluble polymer and the adhesive consisting of a polyolefin resin. Examples of nonionic surfactants include, but are not limited to, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene dialkyl ethers, polyoxyethylene fatty acid esters, glycerin fatty acid esters, and sucrose fatty acid esters.

The content of the surfactant in the ink receiving layer is preferably 5 to 15 parts by mass per 100 parts by mass of the adhesive. If the content of the surfactant is less than 5 parts by mass per 100 parts by mass of the adhesive, the effect of suppressing aggregation between the water-soluble polymer and the adhesive may be insufficient, and if it exceeds 15 parts by mass, the adhesive strength during textile transfer may decrease, or ink bleeding may occur during printing by the inkjet method.

(Other additives)
The ink receiving layer may contain additives such as inorganic fine particles, ink fixing agents, sizing agents, coloring dyes, coloring pigments, defoaming agents, fluorescent brightening agents, viscosity adjusting agents, and lubricants.

The ink receiving layer may contain one or more inorganic fine particles such as light calcium carbonate, heavy calcium carbonate, kaolin, silica particles, clay, magnesium carbonate, magnesium hydroxide, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, alumina, colloidal alumina, alumina hydrate (pseudoboehmite, etc.), aluminum hydroxide, lithopone, zeolite, and hydrated halloysite.

In addition, polyamine epichlorohydrin compounds are suitable for use as ink fixing agents because they are highly stable even in high-viscosity paints.

(Production method)
The sublimation inkjet textile transfer paper according to this embodiment can be manufactured by preparing an ink-receiving layer coating material, coating one side of a base paper with the prepared ink-receiving layer coating material, and drying the coating film.

The ink receiving layer paint can be prepared by adding a surfactant to the adhesive dispersion in a mixing tank, stirring to mix, and then adding a water-soluble polymer to the mixture and stirring. By mixing the adhesive and surfactant before mixing the adhesive and water-soluble polymer, the surface of the adhesive is covered with the surfactant, and even if the water-soluble polymer is added, the mutual reaction between the polar functional groups of the water-soluble polymer and the adhesive is suppressed, which is thought to suppress aggregation of the adhesive and the water-soluble polymer. In contrast, if a water-soluble polymer is added to the adhesive dispersion, or if an adhesive dispersion is added to the water-soluble polymer, aggregation between the adhesive and the water-soluble polymer progresses, and the ink receiving layer paint cannot be made non-aggregated even if a surfactant is mixed thereafter.

The median diameter D50 of the fine particles contained in the ink receiving layer paint is preferably 0.5 to 20 μm. The median diameter D50 of the fine particles contained in the ink receiving layer paint is an index that indicates the degree of aggregation of the adhesive and the water-soluble polymer. If the median diameter D50 of the fine particles contained in the ink receiving layer paint is 20 μm or less, clogging of the screen of the coating device, coating defects, defects in the ink receiving layer, etc., described above can be suppressed. The lower limit of the median diameter D50 of the fine particles contained in the ink receiving layer paint is not particularly limited, but since the ink receiving layer paint contains fine particles of polyolefin resin, which is the adhesive, the lower limit is a value that reflects the particle size of the adhesive fine particles. The median diameter D50 shown here is measured using a laser diffraction/scattering type particle size distribution measuring device (manufactured by Microtrack Bell, product name: HRA MT3300).

The method for coating the ink receiving layer is not particularly limited, but it can be coated using a coating machine such as a rod coater, blade coater, or air knife coater.

The coating amount of the ink receiving layer is preferably 2.0 to 12.0 g/ ^m2 per side, more preferably 3.0 to 10.0 g/ ^m2 , and even more preferably 4.0 to 8.0 g/ ^m2 , from the viewpoint of achieving both suppression of ink strike-through and good ink drying properties.

(Dye-sublimation inkjet textile transfer paper)
The adhesive strength between the dye-sublimation inkjet textile transfer paper and the polyester fabric after the dye-sublimation inkjet textile transfer paper according to the present embodiment and the polyester fabric are superimposed and heat-pressed at 200° C. for 30 seconds is preferably 0.15 to 2 N/100 mm. If the adhesive strength is within this range, the adhesion between the dye-sublimation inkjet textile transfer paper and the transferee can be maintained during the textile transfer, suppressing misalignment between the two, and suppressing transfer of the adhesive to the transferee when the dye-sublimation inkjet textile transfer paper is peeled off after the textile transfer. Even within the above range, the adhesive strength between the dye-sublimation inkjet textile transfer paper and the polyester fabric after heat-pressing at 200° C. for 30 seconds is more preferably 0.2 to 1 N/100 mm, and even more preferably 0.3 to 0.6 N/100 mm.

(Backcoat Layer)
A backcoat layer may be provided on the other side of the base paper of the dye-sublimation inkjet textile transfer paper according to this embodiment, i.e., on the side opposite to the side on which the ink receiving layer is formed. The backcoat layer prevents the sublimation gas from passing through to the paper surface during textile transfer. It also adjusts the moisture difference between the front and back, and reduces the curl height.

The backcoat layer preferably contains, as inorganic particles, delaminated kaolin having a median diameter D50 in the range of 1.50 to 3.00 μm and an aspect ratio of more than 20. The particle diameter (median diameter D50 ) of the inorganic particles shown here is measured using a laser diffraction/scattering type particle size distribution measuring device (manufactured by Microtrack Bell, product name: MT3300).

As other inorganic particles, inorganic pigments such as kaolin, silica particles, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, magnesium hydroxide, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, alumina, colloidal alumina, alumina hydrate (pseudoboehmite, etc.), aluminum hydroxide, lithopone, zeolite, hydrated halloysite, etc. can be contained, so long as the effect of the dye-sublimation inkjet textile transfer paper is exhibited. These can be used alone or in combination of two or more types.

The backcoat layer preferably contains tapioca starch and SB latex as binders. The backcoat layer further preferably contains polyethylene glycol (hereinafter also referred to as PEG).

(Air permeability)
The air permeability of the dye-sublimation inkjet textile transfer paper according to the present embodiment is preferably 100 to 10,000 seconds, more preferably 500 to 1,500 seconds. The air permeability is a measured value in accordance with JIS P 8117 (2009). By having the air permeability value within this range, the sublimated ink can be transferred well from the ink receiving layer to the transferee, and the sublimated ink can be prevented from leaking to the back side of the base paper. If the air permeability is less than 100 seconds, the sublimated ink will leak to the back side of the paper and stain the transfer heat roll or heat plate, which is not preferable. On the other hand, if the air permeability exceeds 10,000 seconds, the moisture in the ink receiving layer will not penetrate the base paper, resulting in poor drying properties, and the moisture in the ink receiving layer will not escape during thermal transfer, which may cause blisters, which is not preferable.

As described above, the dye-sublimation inkjet textile transfer paper according to this embodiment has excellent adhesion during textile transfer because the ink-receiving layer contains a polyolefin resin as an adhesive, and can suppress transfer misalignment of the image even if the transferee is a stretchable cloth material. In addition, the dye-sublimation inkjet textile transfer paper according to this embodiment has a configuration in which one ink-receiving layer is provided on one side of the base paper, so that ink receptivity and transferability can be improved compared to a configuration in which a layer for imparting adhesiveness to the surface of an ink-receiving layer is laminated, and the number of steps during manufacturing can be reduced, thereby improving production efficiency. In addition, because the ink-receiving layer is formed from a paint containing an adhesive, a water-soluble polymer, and a surfactant, the dye-sublimation inkjet textile transfer paper can have fewer coating defects caused by agglomerates of the adhesive and the water-soluble polymer.

The following describes specific examples of the dye-sublimation inkjet textile transfer paper of the present invention. However, the present invention is not limited to these examples.

<Examples of base paper manufacturing>
A stock was prepared by adding heavy calcium carbonate and talc as fillers to a mixture of 80% by mass of LBKP and 20% by mass of NBKP so that the ash content was 8.0%, and 0.8% by mass of cationic starch, 0.3% by mass of alkyl ketene dimer (internal sizing agent), and 0.3% by mass of anion-modified polyacrylamide to a total of 100% by mass of kraft pulp. This stock was made on a papermaking machine, and a base paper was obtained in which the time until the ultrasonic transmission intensity of the initial water absorption properties reached 100% (EST sizing degree) was 1.50 seconds, as measured with a surface/sizing degree tester (EST12, made by emtec).

The following materials were used as components of the ink receiving layer coating.
(Adhesive)
Polyolefin resin (ethylene-methacrylic acid copolymer) emulsion (water-soluble polymer)
・CMC: FINFIX (manufactured by Sansho Co., Ltd.)
Hydroxylated cellulose: SANHEC (manufactured by Sansho Co., Ltd.)
PVA: Kuraray Poval 105 (manufactured by Kuraray Co., Ltd.)
(Surfactant)
・Polyoxyethylene alkyl ether

(Examples 1 to 10 and Comparative Example 2)
To 100 parts by mass of adhesive dispersed in water, the parts of surfactant shown in Table 1 were added and mixed, and then the parts of water-soluble polymer shown in Table 1 were further added and mixed to prepare an ink-receiving layer coating. The units of content (parts) shown in Table 1 are parts by mass, and the values for adhesive and water-soluble polymer indicate the content ratio converted into solid content. The ink-receiving layer coating was applied to one side of the base paper using a rod coater and dried to form an ink-receiving layer. The coating amount of the ink-receiving layer coating (after drying) was as shown in Table 1.

(Comparative Example 3)
A primer coating was prepared by mixing 8.0 parts by weight of EVA, 4.0 parts by weight of PVA, and 12.0 parts by weight of ink fixing agent with 100 parts by weight of light calcium carbonate. The primer coating was applied to one side of the base paper using a rod coater and dried to form a primer coating layer, and an adhesive was applied to the upper layer using a rod coater to form an adhesive layer. The coating amount of the primer coating (after drying) was 5.0 g/ ^m2 (after drying), and the coating amount of the adhesive was 7.0 g/ ^m2 .

(Comparative Example 1)
An ink-receiving layer coating material was prepared by adding and mixing the water-soluble polymer in the amount shown in Table 1 to 100 parts by mass of the adhesive dispersed in water. The ink-receiving layer coating material was applied to one side of the base paper using a rod coater and dried to form an ink-receiving layer. The coating amount of the ink-receiving layer coating material (after drying) was as shown in Table 1.

(Comparative Example 4)
An ink-receiving layer coating material was prepared by adding an adhesive to a water-soluble polymer dissolved in water and mixing. The amount of the water-soluble polymer was the number of parts shown in Table 1 per 100 parts by mass of the adhesive. The ink-receiving layer coating material was applied to one side of the base paper using a rod coater and dried to form an ink-receiving layer. The coating amount of the ink-receiving layer coating material (after drying) was as shown in Table 1.

Table 1 shows the median diameter D50 of the fine particles contained in the coating liquid and the presence or absence of aggregation during preparation of the ink receiving layer coating material. The median diameter D50 is measured using a laser diffraction/scattering type particle size distribution measuring device (manufactured by Microtrac Bell, product name: HRA MT3300). The presence or absence of aggregation was evaluated according to the following criteria by visually observing the stainless steel screen mesh after pouring the coating liquid into a stainless steel screen mesh (250 mesh/inch), adding water and filtering it.
⊚: No residue was observed on the screen mesh.
◯: Almost no residue was observed on the screen mesh.
Δ: A small amount of residue was observed on the screen mesh.
×: A large amount of residue was found on the screen mesh, or the coating liquid did not pass through the screen mesh.

The resulting dye-sublimation inkjet textile transfer paper was evaluated using the following methods.

(1) Bleeding Using an inkjet printer (Seiko Epson Corporation, SC-F9350) and dye-sublimation printing inks (Seiko Epson Corporation, SC5HDK100P (black), SC5C100P (cyan), SC5M100p (magenta), and SC5Y100P (yellow)), a model image was printed on dye-sublimation inkjet textile transfer paper at 720 dpi x 720 dpi. The printed surface of the dye-sublimation inkjet textile transfer paper was visually observed, and the presence or absence of bleeding was evaluated according to the following evaluation criteria.
.circleincircle.: No bleeding.
B: Slight bleeding was observed, but not to the extent that would cause any practical problems.
×: Bleeding is noticeable.

(2) Drying property Using an inkjet printer (Seiko Epson Corporation, SC-F9350) and dye-sublimation printing inks (Seiko Epson Corporation, SC5HDK100P (black), SC5C100P (cyan), SC5M100P (magenta), and SC5Y100P (yellow)), a 100% black solid print was made on dye-sublimation inkjet printing transfer paper at 720 dpi x 720 dpi. One minute after printing, the printed surface was rubbed with tissue paper, and when it was wiped off, the presence or absence of ink spreading on the paper surface was visually confirmed, and the drying property was evaluated according to the following evaluation criteria.
⊚: Dries very quickly and the ink does not spread at all on the paper surface after wiping.
◯: Drying is slightly slow, and slight spreading of the ink on the paper surface after wiping is observed, but this is not a problem in practical use.
×: Drying is slow, and ink spreading is observed on the paper surface after wiping.

(3) Strike-through After printing the four colors CMYK on a dye-sublimation inkjet textile transfer paper using an inkjet printer, the paper was placed on top of a polyester fabric and then heat-pressed with a flatbed transfer machine at 200°C for 90 seconds to transfer the printed image to the polyester fabric. Note that plain paper was placed between the dye-sublimation inkjet textile transfer paper and the hot plate. After transfer, the presence or absence of ink adhesion to the plain paper was visually confirmed and evaluated based on the following evaluation criteria.
⊚: No ink adhesion to the interposed plain paper was observed.
◯: Adhesion of ink to the interposed plain paper was observed, but the amount of adhesion was not a problem in practical use. ×: Adhesion of ink to the interposed plain paper was noticeable, and the amount of adhesion was a problem in practical use.

(4) Density The color density of CMYK of the polyester fabric to which the image was transferred in the above evaluation item (3) was measured using a densitometer (FD-5, manufactured by Konica Minolta Japan, Inc.) and evaluated according to the following evaluation criteria.
◎: High transfer density onto fabric material.
◯: The transfer density onto the fabric material is lower than that of the "Evaluation ⊚" grade, but is not problematic in practical use.
× The transfer density onto the fabric material is low, and the density is problematic in practical use.

(5) Ghosting The polyester fabric to which the image was transferred in the above evaluation item (3) was visually observed, and the presence or absence of transfer misalignment (ghosting) was evaluated according to the following criteria.
.circleincircle.: No transfer misalignment.
◯: slight transfer misalignment is observed, but to an extent that does not cause any practical problems.
×: Transfer misalignment is noticeable.

(6) Layer Peeling The polyester fabric to which the image was transferred in the above evaluation item (3) was visually observed, and the presence or absence of a layer (ink-receiving layer or adhesive layer) peeled off from the base paper was evaluated according to the following criteria.
⊚: No layer remains separated from the base paper.
◯: A small amount of the layer separated from the base paper remains, but this is not problematic for practical use.
Δ: A layer peeled off from the base paper remains.

(6) Heat seal strength A dye-sublimation inkjet textile transfer paper cut to a width of 100 mm and a flow direction of 150 mm was placed on a polyester fabric of the same size, and heat-pressed with a flatbed transfer machine at 200° C. for 30 seconds. After leaving the dye-sublimation inkjet textile transfer paper sealed to the polyester fabric for 5 minutes, the heat seal strength was measured by T-peeling at a tensile speed of 0.5 mm/min using a tensile tester (Strograph E-S, manufactured by Toyo Seiki Seisakusho Co., Ltd.).

The ink receiving layer of the dye-sublimation ink-jet textile transfer paper was visually inspected for the presence or absence of coating defects such as streaks and scratches, and evaluated according to the following criteria.
⊚: No coating defects in the ink receiving layer.
◯: Slight coating defects are observed in the ink receiving layer, but are not noticeable.
Δ: Coating defects are observed in the ink receiving layer, but are not problematic in practical use.
x: Coating defects are conspicuous in the ink receiving layer.

The evaluation results of the dye-sublimation inkjet textile transfer papers of Examples 1 to 10 and Comparative Examples 1 to 4 are shown in Table 2.

The dye-sublimation inkjet textile transfer paper according to Examples 1 to 10 had little bleeding during printing with an inkjet printer, excellent drying properties, and good ink receptivity. In addition, there was little ink bleed-through during textile transfer, the transfer density of the image to the fabric was high, and the heat seal strength (adhesive strength) was good, so ghosts and layer peeling during transfer were also suppressed, and the transfer suitability was good. Furthermore, there were very few coating defects in the ink-receiving layer, and even in Example 8, where coating defects were observed, there were no practical problems. Therefore, it was confirmed that the present invention can realize a dye-sublimation inkjet textile transfer paper with excellent adhesion to the transfer target, good ink receptivity and transfer suitability, and few coating defects. Furthermore, as shown in Table 1, in Examples 1 to 10, there was no problematic aggregation of the paint during preparation of the ink-receiving layer paint.

In contrast, in Comparative Example 1, no surfactant was added, so the adhesive and water-soluble polymer aggregated during preparation of the ink-receiving layer paint, resulting in a large amount of aggregates and noticeable coating defects in the ink-receiving layer.

In Comparative Example 2, a surfactant with an HLB value of less than 10 was used, which did not sufficiently suppress the aggregation of the adhesive and water-soluble polymer. When preparing the ink-receiving layer coating, the adhesive and water-soluble polymer aggregated, producing a large amount of aggregates, and coating defects were noticeable in the ink-receiving layer.

In Comparative Example 3, the undercoat coating layer (ink-receiving layer) and the adhesive layer were formed as separate layers, and the adhesive layer was laminated on top of the undercoat coating layer. This resulted in poor ink receptivity of the undercoat coating layer, and low image transfer density on the fabric after textile transfer.

In Comparative Example 4, because no surfactant was added, the adhesive and water-soluble polymer aggregated during preparation of the ink-receiving layer coating, resulting in a large amount of aggregates and noticeable coating defects in the ink-receiving layer.

The present invention can be used as dye-sublimation inkjet textile transfer paper for transferring patterns to fabric materials (particularly suitable for materials that exhibit elasticity), and since it has excellent adhesion to the substrate, it improves transfer density, reduces uneven printing, and enables high-speed printing (good ink drying properties), making it ideal for use in dye-sublimation inkjet textile transfer paper.

Claims (7)

An ink receiving layer is formed on one side of the base paper,
the ink receiving layer contains a pressure-sensitive adhesive, a surfactant, and a water-soluble polymer;
The pressure-sensitive adhesive is a polyolefin resin,
The surfactant has an HLB value of 10 to 20;
A dye-sublimation ink-jet textile transfer paper, characterized in that the water-soluble polymer is at least one of carboxymethyl cellulose, hydroxylated cellulose, and polyvinyl alcohol. The dye-sublimation inkjet textile transfer paper according to claim 1, wherein the content of the surfactant is 5 to 15 parts by mass per 100 parts by mass of the adhesive. The dye-sublimation inkjet textile transfer paper according to claim 1 or 2, wherein the surfactant is a nonionic surfactant. The dye-sublimation inkjet textile transfer paper according to any one of claims 1 to 3, wherein the content of the water-soluble polymer is 20 to 50 parts by mass per 100 parts by mass of the adhesive. The dye-sublimation inkjet textile transfer paper according to any one of claims 1 to 4, wherein the time it takes for the ultrasonic waves of the initial water absorption characteristics of the base paper to reach 100%, as measured by a surface/sizing degree tester, is 0.01 to 3.00 seconds. A method for producing a dye-sublimation inkjet textile transfer paper, comprising mixing an adhesive and a surfactant, then further mixing a water-soluble polymer with the mixture to prepare an ink-receiving layer coating liquid, and coating the prepared ink-receiving layer coating liquid on at least one side of a base paper,
The pressure-sensitive adhesive is a polyolefin resin,
The surfactant has an HLB value of 10 to 20;
2. A method for producing a dye-sublimation ink-jet textile transfer paper, wherein the water-soluble polymer is carboxymethyl cellulose, hydroxylated cellulose, or polyvinyl alcohol. 7. The method for producing a dye-sublimation inkjet textile transfer paper according to claim 6 , wherein the ink receiving layer coating liquid contains fine particles including an adhesive, and the median diameter D50 of the fine particles contained in the ink receiving layer coating liquid is 0.5 to 20 μm.