JP2020165071A - Transfer paper - Google Patents

Abstract

To provide transfer paper having blocking resistance and good adhesion to a fiber material, color density of a pattern formed on the fiber material, and peeling property of the transfer paper from the fiber material.SOLUTION: There is provided transfer paper that has a base material having one or more non-aqueous resin laminate layers on one side of the base paper, and one or more coating layers on the laminate layer of the base material. In the coating layer, the outermost coating layer contains a white pigment, a binder, and two or more kinds selected from the group consisting of urea, thiourea and dicyandiamide. The binder contains a water-soluble polyester resin, a polyvinyl alcohol resin, an acrylic resin and a polysaccharide. With respect to 20 parts by mass of white pigment in the outermost coating layer, the binder is 50 parts by mass or more and 125 parts by mass or less, urea is 0 parts by mass or more and 3 parts by mass or less, thiourea is 20 parts by mass or more and 50 parts by mass or less, and dicyandiamide is 20 parts by mass or more and 50 parts by mass or less. The value of an ultrasonic transmission attenuation rate after 4 seconds immersion with water is 25% or more.SELECTED DRAWING: None

Description

The present invention relates to a transfer paper used for transferring a pattern in a transfer printing method for forming a pattern on a fiber material. In particular, the present invention relates to a transfer paper suitable when the fiber material is cotton.

In printing paper that can express fine printing patterns and obtain excellent leveling and flexible fiber texture with good reproducibility, the patterns are printed on the printing paper with ink containing dye to obtain printing paper, and the textile material or This is a printing paper used in a transfer printing method in which a dye is transferred by contacting a printing paper with a leather material by heating and pressurizing, and the dye is fixed while the printing paper is attached to a fiber material or a leather material. After applying, spraying or immersing a hydrophilic mixture in which the blending ratio of the natural paste to the water-soluble synthetic binder is in the range of 5% to 0% in terms of solid content and further blending various auxiliaries to the base paper, A textile printing paper having an ink receiving layer and an adhesive layer that is absorbed or laminated on paper by drying is known (see, for example, Patent Document 1).

As a sublimation type inkjet printing transfer paper that can suppress ink strike-through during transfer printing and is less likely to wrinkle even when used in the form of a sheet, a sublimation type printing ink receiving layer is formed on the base material, and the sublimation The pattern printing ink receiving layer is composed of an ink receiving layer coating material containing a water-soluble resin, fine particles A and fine particles B, and the fine particles A have a flat crystal structure and are in the range of 0.4 to 2.3 μm. Inorganic fine particles having a median diameter d50 and an aspect ratio of 5 or more, the fine particles B are silica particles, and the ratio of the fine particles A to the fine particles B (fine particles A / fine particles B) is The mass ratio is 15/85 to 90/10, the water-soluble resin is sodium carboxymethyl cellulose, and the sodium carboxymethyl cellulose is 100 parts by mass in total of the fine particles A and the fine particles B in the ink receiving layer coating material. The amount of the ink receiving layer paint applied (dried) is 3 to 13 g / m ² , and the air permeability is measured according to JIS P 8117: 2009. The air permeability is 100 to 10,000 seconds, and the time required for the ultrasonic transmission intensity of the initial water absorption characteristics measured by the surface / size tester (EST12) to reach 100% is 0.1 to 3.0 seconds. A sublimation type inkjet printing transfer paper characterized by being a base material is known (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2016-102283 Japanese Unexamined Patent Publication No. 2018-03342

In the transfer printing method, the transfer paper and the fiber material are brought into close contact with each other, and the dye received by the transfer paper is transferred to the fiber material. In the printing industry utilizing the transfer printing method, the following items are required from the viewpoint of work efficiency and the quality of the pattern formed on the textile material.
(1) Having blocking resistance between transfer papers.
(2) Good adhesion of the transfer paper to the fiber material.
(3) The color density of the pattern formed on the fiber material is good.
(4) The transfer paper has good peeling from the fiber material after the dye is transferred.
If it is not provided with respect to (1), when the roll-shaped transfer paper normally used in the printing industry is unwound to be brought into close contact with the fiber material, the coating layer may be chipped due to blocking. If there is a significant gap in the coating layer of the portion where the pattern is formed, there will also be a gap in the pattern of the fibrous material formed by transfer. Further, even if there is no significant omission in the design of the transfer paper, color unevenness may occur in the design finally formed on the fiber material. If (2) is not good, the work efficiency of transfer printing is lowered, or the formed pattern is distorted or out of focus. If (3) is not good, it will not be established as a product. If the condition (4) is not good, the work efficiency of transfer printing is lowered or the pattern formed on the fiber material is missing.

In the printing transfer method as described in Patent Document 1, the dye is fixed by a steaming treatment or the like while the transfer paper is in close contact with the fiber material. The reason for this is that the steaming treatment softens the water-soluble synthetic binder and the natural paste, and the transfer paper is easily peeled off from the fiber material. However, in the dye fixing treatment with the transfer paper in close contact with the fiber material, there is a problem of transportation and handling in the fixing treatment device because the adhered material between the transfer paper and the fiber material is thick. Further, in the dye fixing treatment with the transfer paper in close contact with the fiber material, fog may occur during the dye fixing treatment due to the dye remaining on the transfer paper. "Fog" is a phenomenon in which a dye is transferred to a region where a pattern does not originally exist. A typical fog is a spot fog in which dye transfer occurs in a speckled manner in a region where no pattern exists. On the other hand, it is difficult to peel the transfer paper from the fiber material after the transfer paper is brought into close contact with the fiber material and heated and pressed, and before the dye fixing treatment such as steaming treatment is performed. Even if it can be peeled off, defects such as chipping may occur in the pattern formed on the fiber material.

The transfer paper as described in Patent Document 2 is used for sublimation type printing ink. The fiber materials that can be printed with the sublimation type printing ink are limited to those made of polyester fibers, and plant-derived fiber materials such as cotton cannot be printed. Inks containing reactive dyes are used for printing cotton. However, plant-derived fiber materials such as cotton are poor in anionic or cationic charges, and normally charged dyes are difficult to adsorb. As a result, it is difficult to print plant-derived fiber materials such as cotton.

In view of the above, an object of the present invention is that the transfer paper can be peeled off from the fiber material after the fiber material and the transfer paper are brought into close contact with each other, heated and pressurized, and before the dye fixing treatment, that is, the above (4). The present invention is to provide a transfer paper that satisfies the above (1) to (3).

As a result of diligent research to solve the above problems, the present inventor achieves the object of the present invention as follows.

[1] The dye is transferred from the transfer paper to the fiber material by bringing the transfer paper obtained by printing the pattern with the ink containing the dye and the fiber material into close contact with each other and heating and pressurizing, and after the transfer, the transfer paper is transferred from the fiber material. A transfer paper before printing a pattern, which is used in a transfer printing method for peeling and fixing a dye to a fiber material after peeling, and has one or more non-aqueous resin laminate layers on one side of the base paper. The outermost coating layer having one or more coating layers on the laminated layer of the substrate and located at the outermost side of the coating layer with respect to the substrate It contains a white pigment, a binder, and two or more kinds selected from the group consisting of urea, thiourea, and dicyandiamide, and the binder contains at least a water-soluble polyester resin, a polyvinyl alcohol resin, an acrylic resin, and a polysaccharide, and is the outermost. In the coating layer, the binder is 50 parts by mass or more and 125 parts by mass or less with respect to 20 parts by mass of the white pigment in the outermost coating layer, and 20 parts by mass of the white pigment in the outermost coating layer in the outermost coating layer. On the other hand, urea is contained in an amount of 0 parts by mass or more and 3 parts by mass or less, thiourea is contained in an amount of 20 parts by mass or more and 50 parts by mass or less, and dicyandiamide is contained in an amount of 20 parts by mass or more and 50 parts by mass or less, and the permeation time using water is 4 seconds. A transfer paper having an ultrasonic transmission attenuation rate of 25% or more.

[2] The transfer paper according to the above [1], wherein the white pigment in the outermost coating layer contains at least amorphous silica, and the average particle size of the amorphous silica is 10 μm or more and 28 μm or less.
When the average particle size of the white pigment in the outermost coating layer satisfies the above range, the transfer paper improves the adhesion of the transfer paper to the fiber material and / or the peeling of the transfer paper from the fiber material after the dye transfer. To do.

According to the present invention, (1) it has blocking resistance between transfer papers, (2) the adhesion of the transfer paper to the fiber material is good, and (3) the color density of the pattern formed on the fiber material is good. It is possible to provide a transfer paper satisfying that (4) the transfer paper is good at peeling from the fiber material after the dye is transferred.

The present invention will be described in detail below.
In the present invention, the "transfer paper" refers to a paper that is in a blank state before the pattern to be transferred is printed. The “transfer paper” refers to a paper in which a pattern to be transferred is printed on the transfer paper.
Further, in the present invention, "having a layer" means having a clear layer that can be distinguished from the base paper or the base material when the cross section of the transfer paper is observed with an electron microscope. For example, a resin component or a polymer component is coated, and a small amount of the coated component is absorbed by the base paper or the base material, and as a result, when the cross section of the transfer paper is observed with an electron microscope, the base paper or the base material If it does not have a clear layer that can be distinguished from, it does not correspond to "having a layer".

The transfer paper has a base material having one layer or two or more non-aqueous resin laminate layers on one side of the base paper, and one layer or two or more coating layers on the laminate layer of the base material. Among the coating layers, the coating layer located on the outermost side with respect to the base material is called the outermost coating layer. When there is only one coating layer, the coating layer is the outermost coating layer. The outermost coating layer contains a white pigment, a binder, and two or more selected from the group consisting of urea, thiourea and dicyandiamide. The binder contains at least a water-soluble polyester resin, a polyvinyl alcohol resin, an acrylic resin and a polysaccharide. When there are two or more coating layers, the coating layer existing between the base material and the outermost coating layer is a coating layer conventionally known in the field of coated paper, and the presence or absence of a white pigment is present. The type, the presence or absence and type of the binder, and the presence or absence of urea, thiourea and dicyandiamide are not particularly limited. Further, the coating layer existing between the base material and the outermost coating layer can contain various additives conventionally known in the field of coated paper.

From the viewpoint of manufacturing cost of transfer paper, one coating layer is preferable. Further, the coating layer may be provided on one side or both sides of the base material. The coating layer is provided at least on the side of the base material having the laminated layer. When the outermost coating layer according to the present invention is provided on one side of the base material, the transfer paper may have a conventionally known backcoat layer on the back surface of the base material.

The amount of coating of the coating layer is not particularly limited. From the viewpoint of manufacturing cost and ease of handling of the transfer paper, the coating amount is preferably 5 g / m ² or more and 70 g / m ² or less in terms of the amount of dry solids per side. The upper limit of the coating amount is more preferably 30 g / m ² or less. Further, from the viewpoint of reducing the manufacturing cost and preventing the coating layer from being missing when the transfer paper and the fiber material are in close contact with each other, the coating amount is most preferably 10 g / m ² or more and 30 g / m ² or less per side. .. The coating amount is the total value when there are a plurality of coating layers per one side.

The base material is a laminated paper having one or more non-aqueous resin laminated layers on the surface side of the base paper on which at least the outermost coating layer is provided.
When the outermost coating layer of the transfer paper and the fiber material become difficult to peel off, all or part of the coating layer is separated by peeling between the base material and the coating layer including the outermost coating layer. The fiber material can be successfully peeled off from the transfer paper, including the state of being attached to the fiber material. If the transfer printing method is used in which the transfer paper is peeled off from the fiber material and then the fiber material is fixed with a dye, the transfer problem and the handling difficulty in the fixing treatment device can be improved. Furthermore, when the base material is laminated paper, when printing a pattern on transfer paper with ink containing dye, the non-aqueous resin laminate layer prevents the dye from reaching the base paper, which is a drawback to the pattern formed on the fiber material. And the decrease in color density are further suppressed.

The base paper is chemical pulp such as LBKP (Leaf Bleached Kraft Pulp) and NBKP (Needle Bleached Kraft Pulp), GP (Groundwood Pulp), PGW (Pressure GroundWood pulp), RMP (Refiner Mechanical Pulp), TMP (ThermoMechanical Pulp), At least one type of pulp selected from mechanical pulps such as CTMP (ChemiThermoMechanical Pulp), CMP (ChemiMechanical Pulp), CGP (ChemiGroundwood Pulp), and waste paper pulps such as DIP (DeInked Pulp), as well as heavy calcium carbonate, light calcium carbonate, Paper pulp made by blending various fillers such as talc, clay, kaolin and calcined kaolin, and various additives such as sizing agent, fixing agent, yield agent, cationizing agent and paper strength agent as needed. Is. Further, the base paper includes high-quality paper obtained by subjecting papermaking to calendar treatment, surface size treatment with starch, polyvinyl alcohol, or the like, or surface treatment. Further, the base paper includes high-quality paper that has been subjected to surface size treatment or surface treatment and then calendar-treated.

Paper making is performed by adjusting the paper material to acidic, neutral or alkaline and using a conventionally known paper machine. Examples of the paper machine include a long net paper machine, a twin wire paper machine, a combination paper machine, a circular net paper machine, a Yankee paper machine, and the like.

The basis weight of the base paper is not particularly limited. From the viewpoint of ease of handling of the paper, the basis weight of the base paper is preferably 10 g / m ² or more and 100 g / m ² or less, and more preferably 30 g / m ² or more and 100 g / m ² or less.

Other additives such as binders, pigment dispersants, thickeners, fluidity improvers, defoamers, defoaming agents, mold release agents, foaming agents, penetrants, coloring dyes, coloring pigments, etc. The desire of the present invention is one or more selected from fluorescent whitening agents, ultraviolet absorbers, antioxidants, preservatives, antifoaming agents, water resistant agents, wet paper strength enhancers, dry paper strength enhancers and the like. Can be appropriately blended as long as the effect of the above is not impaired.

A base material having a non-aqueous resin laminate layer on at least the surface side of the base paper on which the outermost coating layer is provided can be obtained by providing the non-aqueous resin laminate layer on one side of the base paper. The non-aqueous resin laminate layer has a function of supporting peeling between the transfer paper and the fiber material and a function of preventing the dye from penetrating into the base paper.

The non-aqueous resin that forms the non-aqueous resin laminate layer is a polyolefin resin, a vinyl resin, a resin that is cured by an electron beam, or the like that forms a water-insoluble layer on the base paper. Non-aqueous resins are, for example, polyethylenes such as high density polyethylene, low density polyethylene, medium density polyethylene and linear low density polyethylene; isotactics, syndiotactics, atactics, mixtures thereof, random copolymers with ethylene. And polypropylene such as a block copolymer; in addition, polymethylpentene, polyethylene glycol terephthalate, polyvinyl chloride, polyvinylidene chloride, ethylene vinyl alcohol copolymer, ethylene vinyl acetate copolymer and the like can be mentioned. As the non-aqueous resin, one kind or two or more kinds selected from the group consisting of these can be used.

The method of providing the non-aqueous resin laminate layer on the base paper is not particularly limited. For example, a method using a conventionally known laminator device such as a general melt extrusion die, a T die, or a multi-layer simultaneous extrusion die can be mentioned. The non-aqueous resin laminate layer is one layer or two or more layers on one side of the base paper. From the viewpoint of manufacturing cost, one non-aqueous resin laminate layer is preferable. The thickness of the non-aqueous resin laminate layer is preferably 10 μm or more, more preferably 15 μm or more. The reason for this is that the base paper has sufficient coating properties and the above-mentioned function of the non-aqueous resin laminate layer can be obtained. The thickness of the non-aqueous resin laminate layer is preferably 30 μm or less. The reason for this is that the above function is saturated at 30 μm, and if it exceeds 30 μm, the material cost is high.
When the non-aqueous resin laminate layer is one layer, the thickness of the layer is indicated, and when the non-aqueous resin laminate layer is two or more layers, the total thickness of these layers is indicated.

The coating layer can be provided by coating and drying the coating layer coating liquid on the base material or the lower coating layer.
The method of providing the coating layer is not particularly limited. For example, a method of coating and drying using a coating device and a drying device conventionally known in the papermaking field can be mentioned. Examples of coating equipment include size presses, gate roll coaters, film transfer coaters, blade coaters, rod coaters, air knife coaters, comma coaters (registered trademarks), gravure coaters, bar coaters, E bar coaters, curtain coaters, and the like. be able to. Examples of the drying device include a straight tunnel dryer, an arch dryer, an air loop dryer, a hot air dryer such as a sine curve air float dryer, an infrared heating dryer, a dryer using microwaves, and the like.
In addition, the coating layer can be subjected to calendar treatment after coating and drying.

The binder of the outermost coating layer contains at least a water-soluble polyester resin, a polyvinyl alcohol resin, an acrylic resin and a polysaccharide. By blending these binders in the coating liquid of the outermost coating layer, the outermost coating layer can contain a water-soluble polyester resin, a polyvinyl alcohol resin, an acrylic resin and a polysaccharide.

The water-soluble polyester resin is a resin obtained by polycondensation reaction between a polyvalent carboxylic acid and a polyol, and the polyvalent carboxylic acid and the polyol occupy 60% by mass or more of the resin as constituent components. Examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, adipic acid, succinic acid, sebacic acid, dodecanedioic acid and the like, and one or two kinds from the group consisting of these. It is preferable to select and use the above. Examples of the polyol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, cyclohexanedimethanol, bisphenol, and the like. It is preferable to select one type or two or more types from the group consisting of. In addition, the water-soluble polyester resin can be copolymerized with a component having a hydrophilic group such as a carboxyl group or a sulfonic acid group in order to increase the water solubility.
The water-soluble polyester resin is commercially available from GOO CHEMICAL CO., LTD., Takamatsu Oil & Fat Co., Unitika Ltd., etc., and these commercially available products can be used in the present invention. The term "water-soluble" means that it can be finally dissolved in water at 20 ° C. in an amount of 1% by mass or more.

The polyvinyl alcohol resin is various polyvinyl alcohols having various degrees of saponification and various degrees of polymerization, and various modified polyvinyl alcohols. Examples of the modified polyvinyl alcohol include carboxylic acid-modified polyvinyl alcohol, sulfonic acid-modified polyvinyl alcohol, phosphoric acid-modified polyvinyl alcohol, silanol-modified polyvinyl alcohol, epoxy-modified polyvinyl alcohol, diacetone-modified polyvinyl alcohol, and acetoacetyl-modified polyvinyl alcohol. Can be done. Further, modified polyvinyl alcohol obtained by copolymerizing ethylene, vinyl ether having a long-chain alkyl group, acrylamide, methacrylamide and the like can be mentioned.

The polyvinyl alcohol resin is preferably a carboxylic acid-modified polyvinyl alcohol. The reason for this is that the adhesion of the transfer paper to the fiber material is improved and the peeling of the transfer paper from the fiber material is improved. The carboxylic acid-modified polyvinyl alcohol has a polyvinyl alcohol moiety that has been carboxylic acid-modified by introducing a carboxyl group.
Examples of the carboxylic acid-modified polyvinyl alcohol include those obtained by graft polymerization or block polymerization of polyvinyl alcohol and a vinyl carboxylic acid compound, and those obtained by copolymerizing a vinyl ester compound and a vinyl carboxylic acid compound and then saponifying them. And those obtained by reacting polyvinyl alcohol with a carboxylating agent can be mentioned. Examples of the vinylcarboxylic acid compound include carboxyl groups such as acrylic acid, methacrylic acid, (maleic anhydride) maleic acid, (anhydrous) phthalic acid, (anhydrous) itaconic acid, and (anhydrous) trimellitic acid, or an anhydride-containing compound thereof. Can be mentioned. Examples of the vinyl ester compound include vinyl acetate, vinyl formate, vinyl propionate, vinyl versatic acid, vinyl vivalate and the like. Examples of the carboxylating agent include succinic anhydride, maleic anhydride, acetic anhydride, trimellitic anhydride, phthalic anhydride, pyromellitic anhydride, glutaric anhydride, hydrogenated phthalic anhydride, and naphthalenedicarboxylic acid anhydride. Can be mentioned.
Carboxylic acid-modified polyvinyl alcohol is commercially available from Nippon Synthetic Chemical Industry Co., Ltd., Japan Vam & Poval Co., Ltd., Kuraray Co., Ltd., etc., and these commercially available products can be used in the present invention.
The carboxylic acid-modified polyvinyl alcohol preferably has a number average degree of polymerization of 1000 or more and 3000 or less. Further, the carboxylic acid-modified polyvinyl alcohol preferably has a saponification degree of 85 mol% or more and 90 mol% or less. These reasons are excellent in compatibility with other resins.

Acrylic resin is a general term for polymers or copolymers mainly composed of derivatives such as acrylic acid and its esters, and derivatives such as methacrylic acid and its esters. Examples of the acrylic acid ester include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-dimethylaminoethyl acrylate and 2-hydroxyethyl acrylate. Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, 2-dimethylaminoethyl methacrylate and 2-hydroxyethyl methacrylate. In the present invention, copolymers such as acrylonitrile, acrylamide, and N-methylolacrylamide are also included in the acrylic resin.
Acrylic resins are commercially available from Toagosei, Nippon Shokubai, Shin-Nakamura Chemical Industry, Idemitsu Kosan, Mitsubishi Chemical, etc., and these commercially available products can be used in the present invention.

Polysaccharides are conventionally known saccharides, which are not classified into oligosaccharides in which several or more monosaccharides are dehydrated and condensed by glycosidic bonds, and two to several molecules of monosaccharides and monosaccharides are condensed. In addition, polysaccharides include those that have been chemically modified. Examples of polysaccharides include carrageenan, agar, pectin, xanthan gum, guagam, gellan gum, alginic acid and its salts, tara gum, tragant gum, tamarind seed gum, psyllium seed gum, carrageenan, starch and various modified starches, amylop, pullulan, dextran, Curdlan, lentinan, amylopectin, glycogen, xylan, galactan, mannan, glucomannan, glucomannoglycan, galactoglucomannoglycan, guaran, etc. can be mentioned, and moreover, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl starch, etc. Examples of celluloses include hydroxypropyl starch, methyl cellulose, carboxymethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose and the like.

The polysaccharide is preferably starch and various modified starches. Modified starch can be obtained by processing starch purified from natural plants. Examples of modified starches include hydroxyethylated starch, hydroxypropyl starch, oxidized starch, etherified starch, phosphate-esterified starch, urea phosphate-esterified starch, enzyme-modified starch, and cold water obtained by flush-drying them. It is a soluble starch.

The polysaccharide is preferably hydroxypropyl starch. The reason for this is that the adhesion of the transfer paper to the fiber material is improved and the color density of the pattern formed on the fiber material is improved. Hydroxypropyl starch is a modified starch in which a hydroxypropyl group is introduced by etherifying a part or all of the hydroxyl groups of glucose in a polysaccharide in which glucose is polymerized by a glycosidic bond with propylene oxide.
Hydroxypropyl starch is commercially available from Nissho Kagakusha, Matsutani Chemical Industry Co., Ltd., Ingredion Japan Co., Ltd., etc., and these commercially available products can be used in the present invention.

In the outermost coating layer, the content of each of the water-soluble polyester resin, polyvinyl alcohol resin, acrylic resin and polysaccharide is 5 for 20 parts by mass of the white pigment in the outermost coating layer. It is preferable that the amount of polyvinyl alcohol resin is 10 parts by mass or more and 35 parts by mass or less, acrylic resin is 5 parts by mass or more and 25 parts by mass or less, and polysaccharide is 10 parts by mass or more and 50 parts by mass or less. Further, in the outermost coating layer, the total content of the binder is 50 parts by mass or more and 125 parts by mass or less with respect to 20 parts by mass of the white pigment in the outermost coating layer.

The outermost coating layer may contain a binder conventionally known in the field of coated paper, in addition to the water-soluble polyester resin, polyvinyl alcohol resin, acrylic resin and polysaccharide. Binders include, for example, water-soluble synthetic resins, water-dispersible synthetic resins, resins derived from natural components, and resins obtained by physically or chemically modifying them. Specific examples of the binder include urethane resin, polyamide resin, vinyl acetate resin, styrene-butadiene copolymer resin, styrene-acrylic acid-based copolymer resin, styrene-maleic acid-based copolymer resin, and styrene-acrylic male acid-based copolymer. Examples thereof include a coalesced resin, a water-insoluble polyester resin, a polyvinyl acetal resin, a protein, casein, and gelatin.

In the outermost coating layer, the total amount of the water-soluble polyester resin, polyvinyl alcohol resin, acrylic resin and polysaccharide accounts for 85% by mass or more with respect to the binder in the outermost coating layer.

The white pigment is a white pigment conventionally known in the field of coated paper. White pigments include, for example, heavy calcium carbonate, light calcium carbonate, various kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, silica soil, silicate. Inorganic pigments such as calcium, magnesium silicate, amorphous silica, colloidal silica, aluminum hydroxide, alumina, alumina hydrate, lithopone, zeolite, magnesium carbonate, magnesium hydroxide, styrene-based plastic pigments, acrylic-based plastic pigments, styrene -Acrylic plastic pigments, polyethylene, microcapsules, urea resins, melamine resin and other organic pigments can be mentioned.

The white pigment of the outermost coating layer preferably contains at least amorphous silica. The reason for this is that the adhesion of the transfer paper to the fiber material is improved and the peeling of the transfer paper from the fiber material is improved.
Amorphous silica can be roughly classified into wet silica and vapor phase silica depending on the production method. Further, wet silica can be classified into sedimentation silica and gel silica depending on the production method. Sedimentation method silica is produced by reacting sodium silicate and sulfuric acid under alkaline conditions, and the silica particles that have grown particles are aggregated and settled, and then filtered, washed with water, dried, crushed, and classified. Sedimentation silica is, for example, Nipseal (registered trademark) from Toso Silica, Fineseal (registered trademark) and Toxile (registered trademark) from Oriental Silicon Corporation (OSC), and Mizukasil (registered trademark) from Mizusawa Industrial Chemicals, Inc. It is marketed as. Gel silica is produced by reacting sodium silicate and sulfuric acid under acidic conditions. Since the fine particles dissolve during aging and reprecipitate to bond the other primary particles to each other, the gel silica eliminates the distinct primary particles and forms relatively hard aggregated particles with an internal void structure. To do. Gel method silica is commercially available, for example, from Tosoh Silica as Nipgel (registered trademark) and from Grace Japan as Cyroid (registered trademark) and Silojet (registered trademark). Gas phase silica is also called a dry method as opposed to a wet method, and is generally produced by a flame hydrolysis method. Specifically, a method of burning silicon tetrachloride together with hydrogen and oxygen is generally known. Instead of silicon tetrachloride, silanes such as methyltrichlorosilane and trichlorosilane can be used alone or in combination with silicon tetrachloride. Gas-phase silica is commercially available, for example, from Aerosil Japan, Inc. as Aerosil (registered trademark) and from Tokuyama Corporation, Leolosil (registered trademark).
As the white pigment, sedimentation silica is more preferable.

The amorphous silica preferably has an average particle diameter of 6 μm or more, and more preferably an average particle diameter of 10 μm or more. Further, the amorphous silica preferably has an average particle diameter of 40 μm or less, and more preferably an average particle diameter of 35 μm or less. The amorphous silica preferably has an average particle diameter of 10 μm or more and 28 μm or less. The reason for this is that the adhesion of the transfer paper to the fiber material and / or the peeling of the transfer paper from the fiber material after the dye transfer is improved. The average particle size of amorphous silica is a volume-based value obtained by laser diffraction / scattering particle size distribution measurement. The average particle size, which is a volume standard obtained by laser diffraction / scattering type particle size distribution measurement, can be measured and calculated using, for example, a laser diffraction / scattering type particle size distribution measuring device Microtrac MT3000II manufactured by Nikkiso Co., Ltd. Amorphous silica satisfying the average particle size can be obtained, for example, by dry pulverization and / or wet pulverization and sizing of amorphous silica having relatively large particles. Further, as the amorphous silica, a commercially available product satisfying the average particle size can be used.

In addition to the white pigment and the binder, the outermost coating layer can contain various additives conventionally known in the field of coated paper, if necessary. Examples of additives include dispersants, fixers, cationizers, thickeners, fluidity improvers, defoamers, mold release agents, foaming agents, penetrants, colorants, optical brighteners, UV absorption. Examples thereof include agents, antioxidants, preservatives, antifoaming agents and the like.
In addition, the outermost coating layer can contain various conventionally known auxiliaries by the transfer printing method. Auxiliary agents are added to optimize various physical properties of the outermost coating layer coating liquid, or to improve the dyeing property on the printed matter. Examples of the auxiliary agent include various surfactants, pH adjusters, alkaline agents, deep dyeing agents, moisturizers, deaeration agents, reduction inhibitors and the like.

The outermost coating layer contains two or more selected from the group consisting of urea, thiourea and dicyandiamide. In the outermost coating layer, urea is 0 parts by mass or more and 3 parts by mass or less, thiourea is 20 parts by mass or more and 50 parts by mass or less, and dicyandiamide is 20 parts by mass with respect to 20 parts by mass of the white pigment in the outermost coating layer. It is contained in an amount of 50 parts by mass or more.
Urea, thiourea and dicyandiamide have traditionally been added as hydrotropy agents to pretreatment agents for textile materials or printing inks in the field of printing. The reason for this is that in the steaming treatment, which is the fixing treatment of the dye, urea, thiourea and dicyandiamide have the effect of promoting the dyeing of the dye on the fiber material. In particular, urea, thiourea and dicyandiamide are suitable as reactive dyes. On the other hand, urea and thiourea have a dye solvent that increases the solubility of the dye, and dicyandiamide has a property of polycondensation. Due to these properties, problems may occur if the outermost coating layer of the transfer paper contains two or more selected from the group consisting of urea, thiourea and dicyandiamide to promote dye dyeing. there were. The present inventor has found a blending ratio when urea, thiourea and dicyandiamide are contained in the outermost coating layer of the transfer paper, and synergizes with the above-mentioned specific binder and the value of the ultrasonic transmission attenuation rate in the specific range described later. The effect led to the present invention.

If the urea content exceeds 3 parts by mass, the blocking resistance between the transfer papers and / or the color density of the pattern formed on the fiber material deteriorates. If the content of thiourea is less than 20 parts by mass, the adhesion of the transfer paper to the fiber material and / or the peeling of the transfer paper from the fiber material deteriorates. If the content of thiourea is more than 50 parts by mass, the color density of the pattern formed on the fiber material deteriorates. If the content of dicyandiamide is less than 20 parts by mass, the adhesion of the transfer paper to the fiber material and / or the color density of the pattern formed on the fiber material deteriorates. If the content of dicyandiamide is more than 50 parts by mass, the peeling of the transfer paper from the fiber material is deteriorated.

The transfer paper has an ultrasonic transmission attenuation rate of 25% or more at a permeation time of 4 seconds using water. The value of the ultrasonic transmission attenuation rate of the transfer paper at a penetration time of 4 seconds using water is preferably 25% or more and 90% or less. In general, the value of the ultrasonic transmission attenuation rate is 100%, which means that the smaller the% value is, the more water permeates, that is, the larger the value, the more difficult it is for water to permeate. Means. The present inventor has found that this value affects the peeling and adhesion between the transfer paper and the fiber material, and the blocking resistance of the transfer paper.
The ultrasonic transmission attenuation rate passing through the paper changes with time due to the penetration of water. The ultrasonic transmission attenuation rate can be measured using, for example, a dynamic permeability measuring device (DPM) manufactured by Emco under the conditions of a temperature of 23 ° C. and a relative humidity of 50%. In DPM, the paper to be tested is placed in a measuring container filled with water by fixing the paper to the sample holder and allowing water to permeate only from one side of the paper. The ultrasonic waves transmitted from one side of the container pass through the water, the holder, and the test paper fixed to the holder, and reach the receiver installed on the other side. Since the ultrasonic transmission attenuation rate of water and the holder is constant, the change with time of the ultrasonic transmission attenuation rate occurs only due to the change in the ultrasonic transmission of the test paper due to the permeation of water into the paper. The ultrasonic transmission attenuation rate of the transfer paper is measured by fixing the transfer paper to the sample holder so that the surface of the transfer paper having the outermost coating layer is on the water side.

In general, the value of the ultrasonic transmission attenuation factor of coated paper changes with time as follows. In the measurement start time range, as the surface of the coated paper gets wet, the reflection of ultrasonic waves at the interface between the coated paper and water decreases, and the water penetrates into the voids of the coated paper to transmit ultrasonic waves of air. Since the ultrasonic transmission of water is better than that of water, the received signal is increased, and as a result, the value of the ultrasonic transmission attenuation rate is reduced. In the subsequent time zone, as the water permeates the coated paper, the bubbles locally left behind inside the coated paper cause ultrasonic scattering and reduce the received signal, resulting in ultrasonic transmission attenuation. The value of the rate increases. When water completely penetrates the coated paper, the absorption of ultrasonic waves decreases and the received signal increases, resulting in a smaller value of ultrasonic transmission attenuation.
The values of the ultrasonic transmission attenuation rate are, for example, the degree of calendar processing, basis weight, coating amount, type and content of white pigment in the coating layer, binder type and content, and content ratio of white pigment and binder. It can be adjusted by adjusting the density and size of the base paper and the content of ionic compounds such as a printability improver. In the calendar processing, when the linear pressure is light, the large voids on the surface are crushed and the internal voids are maintained, and when the linear pressure is medium, the voids on the surface are crushed and the internal voids are maintained, and the linear pressure is strong. If this is the case, the voids on the surface will be crushed and the inside will be densified. In the calendar treatment, when the treatment temperature rises, the binder in the coating layer softens, so that the voids decrease and the value of the ultrasonic transmission attenuation tends to decrease. The softening is more likely to occur with water-soluble polyester resins, polyvinyl alcohol resins and acrylic resins than with polysaccharides such as starches and celluloses. When the amount of coating is small, the amount of binder is relatively large, or the voids in the coated paper are reduced, the value of the ultrasonic transmission attenuation factor in the measurement start time range tends to be small. When the content of the binder increases with respect to the content of the white pigment in the coating layer, the voids in the coating layer decrease, so that the value of the ultrasonic transmission attenuation rate tends to decrease.

The transfer paper of the present invention is made by printing a pattern with an ink containing a dye to make a transfer paper, and the dye is transferred from the transfer paper to the fiber material by bringing the transfer paper and the fiber material into close contact with each other and heating and pressurizing the transfer paper. After that, the transfer paper is peeled off from the fiber material, and then the fiber material is used in a transfer printing method in which a dye fixing treatment such as a steaming treatment is performed.

Examples of the ink containing a dye include an ink containing a dye selected from a reactive dye, an acidic dye, a metal complex salt type dye, a direct dye, a disperse dye, a sulfur dye, a bat dye and a cationic dye. The transfer paper of the present invention is suitable for inks containing reactive dyes.

The ink containing the reactive dye can be prepared by adding the reactive dye as a coloring material to various solvents such as water and alcohol. If necessary, the ink can contain various conventionally known auxiliaries such as dispersants, resins, penetrants, moisturizers, thickeners, pH adjusters, antioxidants and reducing agents. Inks containing reactive dyes are commercially available and available.

The transfer paper can be obtained by printing a pattern on the transfer paper with an ink containing a dye. Printing is performed on the side of the transfer paper having the outermost coating layer. Examples of the printing method include a gravure printing method, a screen printing method, and an inkjet printing method. As a method for printing a pattern, an inkjet printing method is preferable because the image quality and the degree of freedom of the ink used are relatively high.

The heating and pressurization in which the transfer paper and the fiber material are brought into close contact with each other is that the printed surface of the transfer paper on which the pattern is printed and the printing surface of the fiber material are brought into close contact with each other and heated and pressed in a close contact state. .. The conditions of heating and pressurizing in close contact are the conditions conventionally known in the transfer printing method. Examples of the method of heating and pressurizing the transfer paper in close contact with the fiber material include a method of heating and pressurizing the transfer paper in close contact with the fiber material using a press machine, a heating roll, a heating drum and the like.

The peeling of the transfer paper from the fiber material is to physically peel the transfer paper from the fiber material in close contact with the transfer paper. The method of peeling is a conventionally known method and is not particularly limited. Examples of the method include a method of peeling off the roll-shaped transfer paper and the fiber material in which the transfer paper and the fiber material are attached by individually winding them on a roll.

The dye fixing treatment is a treatment for fixing the dye transferred from the transfer paper to the fiber material to the fiber material, and is a treatment method conventionally known in the field of printing. Examples of the dye fixing treatment include steaming treatment, humidification treatment, and dry heat treatment at a high temperature. The dye fixing treatment is preferably a steaming treatment. The steaming treatment is also called a wet fixing treatment and is a conventionally known treatment. Typical steaming treatments include a normal pressure steaming method, an HT steaming method, and an HP steaming method. Generally, the normal pressure steaming method is a wet heat treatment at about 105 ° C. for 10 minutes or more and 15 minutes or less, and the HT steaming method is a wet heat treatment at 150 ° C. or more and 180 ° C. or less for 5 minutes or more and 10 minutes or less, the HP steaming method. Then, the dye is fixed to the fiber material by a moist heat treatment at 120 ° C. or higher and 135 ° C. or lower and 20 minutes or longer and 40 minutes or lower.

The fiber material may be either a natural fiber material or a synthetic fiber material. Examples of natural fiber materials include cellulosic fiber materials such as cotton, hemp, lyocell, rayon and acetate, and protein fiber materials such as silk, wool and animal hair. Examples of the synthetic fiber material include polyamide fiber (nylon), vinylon, polysell, polyacrylic and the like. Examples of the structure of the fiber material include woven fabrics, knitted fabrics, non-woven fabrics and the like alone, blended fabrics, mixed fibers or mixed weaves. Further, these configurations may be compounded.
The transfer paper of the present invention is suitable for natural fiber materials, and is particularly suitable for cotton.

Hereinafter, the present invention will be described in more detail by way of examples. The present invention is not limited to these examples. Here, "parts by mass" and "% by mass" represent "parts by mass" and "% by mass" of the amount of dry solids or the amount of substantial components, respectively. The coating amount of the coating layer represents the amount of dry solid content.

<Base paper>
To a pulp slurry consisting of 100 parts by mass of LBKP with a drainage degree of 380 mlcsf, 10 parts by mass of calcium carbonate, 1.2 parts by mass of amphoteric starch, 0.8 parts by mass of sulfate band, and 0.1 parts by mass of alkyl keten dimer type sizing agent were added as fillers. It was added and made with a Nagami paper machine, and 1.5 g / m ^{2 of} oxidized starch was attached to both sides with a size press device, and machine calendar processing was performed to prepare a base paper with a basis mass of 50 g / m ² . ..

<Base material 1>
High-density polyethylene was laminated on one side of the base paper to a thickness of 15 μm using a melt-extruded die to obtain a base material 1 having a non-aqueous resin laminate layer.

<Base material 2>
The base paper was used as the base material 2.

<Coating layer coating liquid>
In each Example and each Comparative Example, a coating layer coating liquid was prepared with the following composition using water as a medium. Finally, the concentration of the coating layer coating liquid was set to 15% by mass.
The number of parts of the water-soluble polyester resin is shown in Tables 1 to 4, the number of parts of the carboxylic acid-modified polyvinyl alcohol is shown in Tables 1 to 4, the number of parts of the acrylic resin is shown in Tables 1 to 4, and the number of parts of hydroxypropyl starch is shown in Tables 1 to 4. The type and number of copies are shown in Tables 1 to 4. 10 parts by mass of fatty acid ester. The number of parts of urea is shown in Tables 1 to 4. The number of parts of thiourea is shown in Tables 1 to 4. The number of parts of dicyandiamide is shown in Tables 1 to 4. Defoamer 0.15 parts by mass. 25 parts by mass of sodium carbonate

In Tables 1 to 4, Pluscoat (registered trademark) RZ-142 manufactured by GOO CHEMICAL CO., LTD. Was used as the water-soluble polyester resin. As the carboxylic acid-modified polyvinyl alcohol resin as the polyvinyl alcohol resin, Kuraray Poval (registered trademark) 25-88KL of Kuraray Co., Ltd. was used. As the acrylic resin, NK binder M-302HN manufactured by Shin-Nakamura Chemical Industry Co., Ltd. was used. Piostarch (registered trademark) H manufactured by Nissho Kagaku Co., Ltd. was used as the polysaccharide, and Mizusawa Industrial Chemicals Co., Ltd. Mizukasil P-603 (average particle size 6 μm) was used as the amorphous silica A. As the amorphous silica B, Toxil NP (average particle diameter 10.3 μm) manufactured by OSC was used. As the amorphous silica C, Mizusawa Industrial Chemicals, Ltd. Mizukasil P-78F (average particle size 18 μm) was used. As the amorphous silica D, BM225 (average particle diameter 20.8 μm) manufactured by OSC was used. As the amorphous silica E, amorphous silica (average particle diameter 28 μm) obtained by wet pulverizing and sizing the nip seal AQ manufactured by Toso Silica Co., Ltd., which has an average particle diameter of about 100 μm, was used. As the amorphous silica F, amorphous silica (average particle diameter 35 μm) obtained by wet pulverizing and sizing the nip seal AQ of Toso Silica Co., Ltd., which has an average particle diameter of about 100 μm, was used.

<Transfer paper>
Coating layer The coating liquid was coated on one side of the base material using an air knife coater and dried using a hot air dryer, and the coating layer was used as the outermost coating layer. After that, a calendar process was performed to finally prepare a roll-shaped transfer paper. The coating amount of the outermost coating layer is 12 g / m ² for Examples 12 and 13 and Comparative Example 13, and 15 g / m ² for Examples 1 to 11 and 14 to 18 and Comparative Examples 1 to 12. The linear pressure and temperature conditions of the calendar processing were adjusted so that the value of the transmission attenuation factor became a predetermined value.
In the base material 1 having the non-aqueous resin laminated layer, the outermost coating layer was provided on the side having the laminated layer.
In Comparative Examples 12 and 13, the ratio of the content of the binder to the content of the white pigment in the outermost coating layer does not satisfy the conditions of the present invention. Comparative Example 12 is a design in which the content ratio of the binder in the outermost coating layer is considerably higher than the content of the white pigment conventionally existing in the field of transfer printing method. Comparative Example 13 is a design in which the binder is 5 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of a white pigment conventionally known in the field of inkjet paper in the coating layer.

<Value of ultrasonic transmission attenuation factor>
The value of the ultrasonic transmission attenuation factor of the transfer paper with respect to water was measured using DPM manufactured by Emco. The transfer paper was fixed to the sample holder so that the surface of the transfer paper having the outermost coating layer was located on the water side. The value 4 seconds after the start of measurement was read with the ultrasonic frequency set to 2 MHz.

<Transfer paper>
Using an inkjet printer (ValueJet (registered trademark) VJ-1628TD, manufactured by Muto Kogyo Co., Ltd.) in which ink containing a reactive dye is set on a roll-shaped transfer paper, the ink (on the side having the outermost coating layer of the transfer paper) ( The evaluation pattern was printed with cyan, magenta, yellow, and black), and finally a sheet-shaped transfer paper was obtained. As the ink containing the reactive dye, NOVACRON (registered trademark) MI ink manufactured by Huntsman was used.

<Evaluation of blocking resistance>
The roll-shaped transfer paper was unwound from the unwinder. Regarding the part where the pattern of the unwound transfer paper is printed, the pattern is missing due to the components of the coating layer adhering to the back surface of the transfer paper in contact with the printed part of the transfer paper, and the textile material is formed. The state of occurrence of color unevenness was visually observed, and sensory evaluation was performed according to the following criteria. The evaluation results are shown in Tables 1 to 4. In the present invention, if the evaluation is A, B or C, the transfer paper is assumed to have blocking resistance.
A: Good with no adhesion, no omission, and no color unevenness.
B: Although there is very little adhesion, there is no serious omission and there is no color unevenness, and it is generally good.
C: Although there is slight adhesion, there is no serious omission and there is very little color unevenness, so it is practical.
D: Adhesive, missing, and uneven color, impractical.

<Transfer printing>
A scroll cotton cloth that had not been pretreated was used as the fiber material. The printed surface of the transfer paper and the printing surface of the cotton cloth were conveyed facing each other, and were brought into close contact with each other by a roll nip method equipped with a heating roll to heat and pressurize. The conditions of heating and pressurization were a temperature of 120 ° C., a linear pressure of 70 kg / cm, and a time of 0.5 seconds.

<Peeling of transfer paper>
The transfer paper was peeled off from the cotton cloth on which the transfer paper was attached by winding the transfer paper and the cotton cloth individually on a roll.

<Evaluation of peeling>
When the transfer paper was peeled from the cotton cloth, the state of the peeled surface of the cotton cloth and the state of the peeled surface of the cotton cloth after washing with water were observed. From the state of the peeled surface, sensory evaluation was performed according to the following criteria. The evaluation results are shown in Tables 1 to 4. In the present invention, if the evaluation is A or B, it is assumed that the transfer paper has good peeling from the cotton cloth.
A: It can be easily peeled off, even if the components of the outermost coating layer are attached.
It can be easily removed by washing with water later, and there is no omission in the formed pattern.
B: Although the components of the outermost coating layer are attached, they can be peeled off.
By subsequent washing with water, the adhered components can be removed, and the formed pattern is not missing.
C: It is difficult or impossible to peel off, and there is a part where the transfer paper is torn and remains in close contact.
It is difficult to remove even by washing with water later, or the formed pattern is missing.

<Cotton cloth steaming treatment>
The rolled cotton cloth from which the transfer paper was peeled off was transported from the unwinder to the winder, and during that time, a wet heat treatment was performed at 105 ° C. for 10 to 15 minutes by a normal pressure steaming method.

<Flush>
After steaming, the obtained cotton cloth was washed with running water.

<Evaluation of close contact>
From the viewpoint of distortion and out-of-focus of the pattern formed on the cotton cloth, the good adhesion between the transfer paper and the fiber material was sensory-evaluated according to the following criteria. The evaluation results are shown in Tables 1 to 4. If the evaluation is A, B or C in the present invention, it is assumed that the transfer paper has good adhesion to the fiber material.
A: No distortion or out-of-focus is observed in the design. Good.
B: Distortion and / or out-of-focus are observed in the design.
However, it is generally good.
C: Inferior to B above, with slight distortion and / or out-of-focus.
But standard level.
D: Inferior to C above, distortion and / or out-of-focus are observed.
However, it is a practical level.
E: Inferior to D above, distortion and / or out-of-focus are observed. A level that is not practical.

<Evaluation of color density>
The color density of the solid image part of three colors (cyan, magenta, and yellow) formed on the cotton cloth was measured using an optical densitometer (X-rite (registered trademark) 530, X-Rite Incorporated), and 3 The color density values of the colors were totaled. From the total value, the color density was evaluated according to the following criteria. The evaluation results are shown in Tables 1 to 4. In the present invention, the transfer paper can provide a fiber material having a good color density if it is evaluated as A, B or C.
A: Total value is 4.8 or more B: Total value is 4.6 or more and less than 4.8 C: Total value is 4.4 or more and less than 4.6 D: Total value is 4.2 or more and less than 4.6. Less than 4 E: Total value less than 4.2

The respective evaluation results are shown in Tables 1 to 4.

From Tables 1 to 4, the transfer papers of Examples 1 to 18 corresponding to the present invention have (1) blocking resistance between transfer papers and (2) good adhesion of the transfer paper to the fiber material. It can be seen that (3) the color density of the pattern formed on the fiber material is good, and (4) the transfer paper is well peeled off from the fiber material after the dye is transferred. On the other hand, it can be seen that Comparative Examples 1 to 13 which do not satisfy the configuration of the present invention cannot simultaneously satisfy the effects of (1) to (4) according to the present invention.
Mainly, from the comparison between Examples 1 and 14 to 18, it can be seen that the white pigment in the outermost coating layer preferably has an average particle size of 10 μm or more and 28 μm or less.

Claims (2)

The transfer paper obtained by printing a pattern with an ink containing a dye and the fiber material are brought into close contact with each other, and the dye is transferred from the transfer paper to the fiber material by heating and pressurizing. After the transfer, the transfer paper is peeled off from the fiber material. A transfer paper before printing a pattern, which is used in a transfer printing method for fixing a dye to a fiber material after peeling, and has one or more non-aqueous resin laminate layers on one side of the base paper. The outermost coating layer having one or more coating layers on the laminated layer of the base material and located at the outermost side of the coating layer with respect to the base material is a white pigment. , Binder and two or more selected from the group consisting of urea, thiourea and dicyandiamide, the binder containing at least a water-soluble polyester resin, polyvinyl alcohol resin, acrylic resin and polysaccharide, and the outermost coating layer. The binder is 50 parts by mass or more and 125 parts by mass or less with respect to 20 parts by mass of the white pigment in the outermost coating layer, and 20 parts by mass of the white pigment in the outermost coating layer in the outermost coating layer. A transfer paper containing 0 parts by mass or more and 3 parts by mass or less of urea, 20 parts by mass or more and 50 parts by mass or less of thiourea, and 20 parts by mass or more and 50 parts by mass or less of dicyandiamide, and a permeation time of 4 seconds using water. Transfer paper having an ultrasonic transmission attenuation rate of 25% or more. The transfer paper according to claim 1, wherein the white pigment in the outermost coating layer contains at least amorphous silica, and the average particle size of the amorphous silica is 10 μm or more and 28 μm or less.