Aqueous adhesive composition

Abstract

To provide an aqueous adhesive composition which enables formation of an adhesive layer that is excellent in adhesiveness and wear resistance, and mechanical characteristics.SOLUTION: An aqueous adhesive composition for forming an adhesive layer on a surface of a fabric conveyance member of an inkjet printer contains a (meth)acrylic resin, and water, and contains a first (meth)acrylic resin and a second (meth)acrylic resin having a glass transition temperature Tg2 lower than a glass transition temperature Tg1 of the first (meth)acrylic resin, as the (meth)acrylic resins, wherein the first (meth)acrylic resin contains methyl methacrylate or ethyl methacrylate as constitutional units, and a total content of the methyl methacrylate and the ethyl methacrylate is 10 mass% or more and 41 mass% or less with respect to the total constitutional units of the first (meth)acrylic resin.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an aqueous pressure sensitive adhesive composition. [Background technology]

[0002] Inkjet recording methods are capable of recording high-definition images with a relatively simple device, and have been rapidly developed in various fields. In the process, various studies have been conducted on ejection stability, etc. For example, Patent Document 1 discloses, as a textile printing technique using an inkjet method, a conveying device and an image recording device that are provided with a displacement suppressing member for a conveying member, for the purpose of stabilizing the contact state between a removing member and a conveying member and improving the recovery performance of cleaning water by the removing member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-109036 A Summary of the Invention [Problem to be solved by the invention]

[0004] As shown in Patent Document 1, in a textile printing technique using an inkjet system, a cloth is attached to a transport member such as an endless belt, and the cloth is transported to a printing section. An adhesive is applied to the surface of the transport member, and the surface of the transport member has adhesiveness. The adhesive is also called a backing agent.

[0005] After printing, the cloth that will become the recording medium is peeled off from the transport member and transported to the next process. However, since the cloth will be reattached to the transport member after it has been peeled off, it is necessary to remove ink, lint, and other remaining materials that have adhered to the transport member during the printing process. Usually, the remaining materials that have adhered to the transport member are washed off with water. In that case, a brush, sponge, etc. may be used to clean the transport member.

[0006] In inkjet printing, the adhesive used is generally a hydrophobic resin dissolved in an organic solvent so as to withstand water washing. In recent years, however, there has been a demand for water-based adhesives that use less organic solvents in order to reduce environmental impact and improve the working environment. However, water-based adhesives have poor abrasion resistance, and the adhesiveness of the adhesive applied to the surface of the transport member tends to gradually decrease with washing, and it is necessary to apply new adhesive every time washing is performed multiple times. [Means for solving the problem]

[0007] The aqueous adhesive composition of the present invention is an aqueous adhesive composition for forming an adhesive layer on the surface of a fabric transport member of an inkjet printing device, and comprises a (meth)acrylic resin and water, the (meth)acrylic resin comprising a first (meth)acrylic resin and a second (meth)acrylic resin having a glass transition temperature Tg2 lower than a glass transition temperature Tg1 of the first (meth)acrylic resin, the first (meth)acrylic resin comprising methyl methacrylate or ethyl methacrylate as a constituent unit, and a total content of the methyl methacrylate and the ethyl methacrylate is 10% by mass or more and 41% by mass or less based on the total of the constituent units of the first (meth)acrylic resin.

[0008] The method for imparting tackiness of the present invention comprises a step of adhering the aqueous pressure-sensitive adhesive composition to the surface of a fabric-transporting member of an ink-jet textile printing apparatus to form a pressure-sensitive adhesive layer.

[0009] The inkjet printing apparatus of the present invention has a transport mechanism which transports a fabric by laminating it to an adhesive layer made of the aqueous adhesive composition formed on the surface of a fabric transport member, a recording section which performs textile printing recording on the fabric attached to the adhesive layer using an inkjet head, and a cleaning section which cleans the adhesive layer from which the fabric has been peeled off after the textile printing recording.

[0010] The inkjet textile printing method of the present invention includes a transporting step of attaching a fabric to an adhesive layer made of the above-mentioned aqueous adhesive composition formed on the surface of a fabric transporting member of an inkjet textile printing device and transporting the fabric, a recording step of performing textile printing recording on the fabric attached to the adhesive layer using an inkjet head, and a cleaning step of cleaning the adhesive layer from which the fabric has been peeled off after the textile printing recording. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic cross-sectional view of an ink-jet textile printing apparatus. [Diagram 2] Table 1 shows the compositions of (meth)acrylic resins A to I. [Diagram 3] Table 2 shows the composition of the aqueous pressure sensitive adhesive composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings as necessary, but the present invention is not limited to this, and various modifications are possible without departing from the gist of the present invention. In the drawings, the same elements are given the same symbols, and duplicated explanations will be omitted. Furthermore, unless otherwise specified, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0013] 1. Water-based adhesive composition The aqueous adhesive composition of the present invention (hereinafter, also simply referred to as "aqueous adhesive composition") is an aqueous adhesive composition for forming an adhesive layer on the surface of a fabric transport member of an inkjet printing apparatus, and contains a (meth)acrylic resin and water, and the (meth)acrylic resin contains a first (meth)acrylic resin and a second (meth)acrylic resin having a glass transition temperature Tg2 lower than a glass transition temperature Tg1 of the first (meth)acrylic resin, the first (meth)acrylic resin contains methyl methacrylate or ethyl methacrylate as a constituent unit, and the total content of the methyl methacrylate and the ethyl methacrylate is 10 mass% or more and 41 mass% or less based on the total of the constituent units of the first (meth)acrylic resin.

[0014] In a conventional inkjet printing device, an adhesive layer is formed on a transport member such as an endless belt, and a fabric serving as a recording medium is attached to the adhesive layer. The fabric is then transported to a printing unit, where recording is performed, and the transport member and the fabric are then peeled off.

[0015] As the adhesive for such a fabric transport member, a solvent-based acrylic adhesive has been widely used. However, since the organic solvent of the solvent-based acrylic adhesive volatilizes when the adhesive is applied, there is a concern that the adverse effect on the human body in the working environment is high. In addition, when using a solvent-based acrylic adhesive, an exhaust device must be installed in the working environment of the inkjet printing device, which makes the overall device configuration larger and increases the cost.

[0016] On the other hand, in order to apply an adhesive to a fabric transport member of an inkjet printing device to form an adhesive layer and transport the fabric by adhering it to the adhesive layer, the adhesive layer needs to have a suitable adhesive strength for attaching and peeling off the fabric, while also having abrasion resistance that can withstand washing with water or brushing to remove lint and ink attached to the adhesive layer. However, adhesive layers made of water-based adhesives tend to have low abrasion resistance. Therefore, it has been difficult to form an adhesive layer made of a water-based adhesive that has excellent abrasion resistance and adhesive strength.

[0017] In response to the above problem, the aqueous pressure-sensitive adhesive composition of the present embodiment contains two or more (meth)acrylic resins having different glass transition temperatures and water, and one (meth)acrylic resin contains a predetermined amount of methyl methacrylate or ethyl methacrylate, so that the adhesive layer formed with the aqueous pressure-sensitive adhesive composition of the present embodiment can achieve both adhesive strength and abrasion resistance. Therefore, the adhesive layer functions well as an adhesive layer that adheres the fabric to the fabric transport member during printing, and in the subsequent cleaning process, damage to the adhesive layer can be suppressed even when the adhesive layer is washed with water using physical means such as a brush or sponge. Each component contained in the aqueous pressure-sensitive adhesive composition will be described in detail below.

[0018] 1.1.(Meth)acrylic resin By including the (meth)acrylic resin, the adhesive strength and abrasion resistance of the adhesive layer formed on the fabric transport member are improved. The (meth)acrylic resin may be a water-soluble resin or a resin emulsion dispersed in a water-based catalyst. These are collectively referred to as (meth)acrylic resin in this embodiment. By using the (meth)acrylic resin, the environmental burden caused by organic solvents can be reduced, and the peelability of the fabric in the adhesive layer also tends to be improved.

[0019] The (meth)acrylic resin is not particularly limited as long as it is a polymer obtained by polymerizing a (meth)acrylic monomer such as (meth)acrylic acid or a (meth)acrylic acid ester as one component.

[0020] The aqueous pressure-sensitive adhesive composition contains, as (meth)acrylic resins, a first (meth)acrylic resin and a second (meth)acrylic resin having a glass transition temperature Tg2 lower than the glass transition temperature Tg1 of the first (meth)acrylic resin. By containing two types of (meth)acrylic resins having different glass transition temperatures Tg, adhesive strength and abrasion resistance are improved.

[0021] The glass transition temperature Tg1 of the first (meth)acrylic resin is preferably −25 to 25° C., or may be −20 to 20° C., or −15 to 15° C., or −15 to 10° C. When the glass transition temperature Tg1 is in the above range, the adhesive strength tends to be further improved.

[0022] The glass transition temperature Tg2 of the second (meth)acrylic resin is preferably −70 to −15° C., or may be −65 to −20° C., or −60 to −25° C., or −55 to −30° C. When the glass transition temperature Tg2 is in the above range, abrasion resistance tends to be further improved.

[0023] The difference |Tg1-Tg2| between the glass transition temperature Tg1 and the glass transition temperature Tg2 is preferably 10 to 50° C., 15 to 45° C., 20 to 40° C., or may be 25 to 35° C. When the difference |Tg1-Tg2| is within the above range, the adhesive strength and abrasion resistance tend to be further improved.

[0024] The glass transition temperature can be adjusted by the homopolymer glass transition temperature of the polymerizable compound used and the content mass ratio of the polymerizable compound used. The glass transition temperature can be measured by a conventionally known method.

[0025] The first (meth)acrylic resin contains methyl methacrylate (MMA) or ethyl methacrylate (EMA) as a structural unit, and may contain other structural units.

[0026] The total content of methyl methacrylate (MMA) and ethyl methacrylate (EMA) is 10% by mass or more and 41% by mass or less, preferably 12% by mass or more and 40.5% by mass or less, and more preferably 15% by mass or more and 40% by mass or less, based on the total of the above-mentioned structural units of the first (meth)acrylic resin. By setting the total content of methyl methacrylate and ethyl methacrylate contained in the first (meth)acrylic resin within the above range, the adhesive strength and abrasion resistance of the adhesive layer are improved.

[0027] The other constituent units are not particularly limited, but examples thereof include (meth)acrylic monomers having an aliphatic group having 4 or more carbon atoms, such as butyl methacrylate (BMA), butyl acrylate (BA), and 2-ethylhexyl acrylate (2EHA); and (meth)acrylic monomers having an aromatic group, such as styrene (St). The first (meth)acrylic resin may be a copolymer of a (meth)acrylic monomer and another monomer. The other monomers are not particularly limited, but examples thereof include acrylamide and acrylonitrile.

[0028] The first (meth)acrylic resin preferably contains a (meth)acrylic monomer having a homopolymer glass transition temperature Tg of −40° C. or lower. Such a monomer is not particularly limited, but examples thereof include butyl acrylate (BA) and 2-ethylhexyl acrylate (2EHA).

[0029] The content of such (meth)acrylic monomers having a Tg of -40°C or less is preferably 30% by mass to 60% by mass, 35% by mass to 55% by mass, or 40% by mass to 50% by mass, based on the total of the above-mentioned structural units of the first (meth)acrylic resin. By setting the content of the (meth)acrylic monomers having a Tg of -40°C or less within the above ranges, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0030] The combination of monomers contained in the first (meth)acrylic resin is not particularly limited, but preferably includes at least ethyl methacrylate, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate, at least ethyl methacrylate, styrene, butyl acrylate, and 2-ethylhexyl acrylate, at least ethyl methacrylate, styrene, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate, and at least methyl methacrylate, butyl methacrylate, and 2-ethylhexyl acrylate. By using the first (meth)acrylic resin containing the above monomers, adhesion and abrasion resistance tend to be further improved.

[0031] Monomers that the second (meth)acrylic resin may contain as a constituent unit are not particularly limited, and examples thereof include (meth)acrylic monomers having an aliphatic group having 3 or less carbon atoms, such as methyl methacrylate (MMA), ethyl methacrylate (EMA), n-propyl methacrylate (PMA), etc.; (meth)acrylic monomers having an aliphatic group having 4 or more carbon atoms, such as butyl methacrylate (BMA), butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), etc.; and (meth)acrylic monomers having an aromatic group, such as styrene (St).

[0032] The second (meth)acrylic resin preferably contains a (meth)acrylic monomer having a homopolymer glass transition temperature Tg of 0° C. or more and 35° C. or less. Such a monomer is not particularly limited, but examples thereof include butyl methacrylate (BMA).

[0033] The content of such (meth)acrylic monomers having a Tg of 0° C. to 35° C. is preferably 5% by mass to 35% by mass, 10% by mass to 30% by mass, or 15% by mass to 25% by mass, based on the total of the structural units of the second (meth)acrylic resin. By setting the content of the (meth)acrylic monomers having a Tg of 0° C. to 35° C. within the above ranges, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0034] The second (meth)acrylic resin preferably contains a (meth)acrylic monomer having a homopolymer glass transition temperature Tg of −40° C. or lower. Such a monomer is not particularly limited, but examples thereof include butyl acrylate (BA) and 2-ethylhexyl acrylate (2EHA).

[0035] The content of such (meth)acrylic monomers having a Tg of -40°C or less is preferably 55% by mass to 85% by mass, 60% by mass to 80% by mass, or 65% by mass to 76% by mass, based on the total of the structural units of the second (meth)acrylic resin. By setting the content of the (meth)acrylic monomers having a Tg of -40°C or less within the above ranges, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0036] The combination of monomers contained in the second (meth)acrylic resin is not particularly limited, but preferably includes at least ethyl methacrylate, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate, and at least n-propyl methacrylate, butyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate. By using the second (meth)acrylic resin containing the above monomers, the adhesive strength and abrasion resistance tend to be further improved.

[0037] The content of the first (meth)acrylic resin in the composition is preferably 40% by mass or more, 45% by mass to 85% by mass, 50% by mass to 82% by mass, 55% by mass to 80% by mass, or 60% by mass to 70% by mass, based on the total amount of the first (meth)acrylic resin and the second (meth)acrylic resin. By having the content of the first (meth)acrylic resin within the above range, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0038] The content of the second (meth)acrylic resin is preferably less than 60% by mass, 10% to 55% by mass, 15% to 50% by mass, or 20% to 45% by mass, based on the total amount of the first (meth)acrylic resin and the second (meth)acrylic resin. By having the content of the second (meth)acrylic resin within the above range, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0039] The content of the (meth)acrylic resin is preferably 20% by mass to 70% by mass, 30% by mass to 60% by mass, 35% by mass to 55% by mass, or 40% by mass to 52% by mass, based on the total amount of the aqueous pressure-sensitive adhesive composition. When the content of the (meth)acrylic resin is 20% by mass or more, the adhesive strength and abrasion resistance of the resulting adhesive layer tend to be improved. When the content of the (meth)acrylic resin is 70% by mass or less, the abrasion resistance of the resulting adhesive layer tends to be improved. The content based on the total amount of the aqueous pressure-sensitive adhesive composition means the amount of solids.

[0040] The content of the first (meth)acrylic resin is preferably 10% by mass to 52% by mass, 15% by mass to 45% by mass, or 20% by mass to 40% by mass, based on the total amount of the aqueous pressure-sensitive adhesive composition. When the content of the first (meth)acrylic resin is within the above range, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0041] The content of the second (meth)acrylic resin is preferably 3% by mass to 40% by mass, 5% by mass to 35% by mass, or 7% by mass to 30% by mass, based on the total amount of the aqueous pressure-sensitive adhesive composition. When the content of the second (meth)acrylic resin is within the above range, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0042] 1.2. Tackifier The aqueous adhesive composition preferably does not contain a tackifier or contains a small amount of it. When the aqueous adhesive composition does not contain a tackifier or contains a small amount of it, the adhesive strength and abrasion resistance of the adhesive layer tend to be easily maintained. Representative examples of such tackifiers include rosin-based compounds, terpene-based compounds, and hydrocarbon resins. More specifically, examples of such tackifiers include rosin-based compounds such as natural rosin, modified rosin, glycerol ester of natural rosin, glycerol ester of modified rosin, pentaerythritol ester of natural rosin, and pentaerythritol ester of modified rosin; terpene-based compounds such as copolymers of natural terpene, three-dimensional polymers of natural terpene, aromatic modified terpene resins, hydrogenated derivatives of aromatic modified terpene resins, terpene phenolic resins, and terpene resins (monoterpene, diterpene, triterpene, polypertene, etc.); and hydrocarbon resins such as aliphatic petroleum hydrocarbon resins (C5-based resins), hydrogenated derivatives of aliphatic petroleum hydrocarbon resins, aromatic petroleum hydrocarbon resins (C9-based resins) such as styrene oligomers, and hydrogenated derivatives of aromatic petroleum hydrocarbon resins.

[0043] It is preferable that the composition does not contain a tackifier, but if a tackifier is contained, the content is preferably 5% by mass or less, 4% by mass or less, 3% by mass or less, 2% by mass or less, or 1% by mass or less, based on the total amount of the aqueous adhesive composition. When the content of the tackifier is within the above range, the adhesive strength and abrasion resistance of the obtained adhesive layer tend to be easily maintained. From the same viewpoint, the total content of the compound selected from the group consisting of a rosin-based compound, a terpene-based compound, and a hydrocarbon resin is also preferably within the same range as above.

[0044] 1.3.Water The water content is preferably 30 to 80 mass %, 35 to 70 mass %, or 40 to 60 mass %, based on the total amount of the aqueous pressure-sensitive adhesive composition.

[0045] 1.4.Surfactants The aqueous pressure-sensitive adhesive composition may contain a surfactant. The surfactant is not particularly limited, but examples thereof include anionic surfactants, nonionic surfactants, and cationic surfactants.

[0046] Examples of anionic surfactants include alkyl sulfocarboxylates, alkyl diphenyl ether disulfonates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and their salts, N-acyl methyl taurines, alkyl sulfates such as ammonium lauryl sulfate and sodium lauryl sulfate, alkyl sulfate polyoxyalkyl ether sulfates, alkyl sulfate polyoxyethylene alkyl ether phosphates, rosin acid soap, castor oil sulfate, lauryl alcohol sulfate, alkyl phenol phosphates, alkyl phosphates, alkyl aryl sulfonates, diethyl sulfosuccinates, diethyl hexyl cylsulfosuccinates, and dioctyl sulfosuccinates.

[0047] Examples of nonionic surfactants include acetylene glycol surfactants, silicone surfactants, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene hardened castor oil, propylene glycol fatty acid esters, glycerin fatty acid esters, polyglycerin fatty acid esters, sorbitan fatty acid esters, sucrose fatty acid esters, alkyl polyglycosides, alkyl diethanolamides, and alkylamine oxides.Commercially available nonionic surfactants are not particularly limited, but include, for example, Emulgen 123P, 430, and 1108 (Kao Corporation product names), Newcol 1006, 1008, and 1020 (Nippon Nyukazai Co., Ltd. product names), Noigen DL-0415, ET-116B, ET-106A, DH-0300, YX-400, and EA-160 (Dai-ichi Kogyo Seiyaku Co., Ltd. product names).

[0048] Examples of cationic surfactants include alkylamine salts, fatty acid amidoamine salts, monoalkyl quaternary ammonium salts, dialkyl quaternary ammonium salts, trialkyl quaternary ammonium salts, benzalkonium quaternary ammonium salts, benzethonium chloride, and alkylpyridinium salts.

[0049] In the present embodiment, among these, nonionic surfactants are preferred, and more specifically, alkyl ether-based nonionic surfactants are preferred. By using such surfactants, abrasion resistance tends to be maintained.

[0050] The content of the surfactant is preferably 1 to 7 mass %, 2 to 6 mass %, or 3 to 5 mass % relative to the total amount of the aqueous pressure-sensitive adhesive composition.

[0051] 1.5. Organic Solvents The aqueous adhesive composition of the present embodiment preferably does not contain an organic solvent from the viewpoint of reducing the environmental load and the influence on the human body. When the aqueous adhesive composition contains an organic solvent, the content of the organic solvent is preferably 5.0 mass% or less, 0.5 mass% or less, or 0.1 mass% or less based on the total amount of the aqueous adhesive composition. This can reduce the environmental load and can reduce VOC (volatile organic compounds) when using the aqueous adhesive composition, which tends to improve the working environment.

[0052] 1.6.Colorants The aqueous adhesive composition of the present embodiment preferably does not contain a coloring material. When the aqueous adhesive composition contains a coloring material, the content of the coloring material is preferably 1.0 mass% or less, 0.5 mass% or less, or 0.3 mass% or less, based on the total amount of the aqueous adhesive composition. This allows the aqueous adhesive composition of the present embodiment to be clearly distinguished from compositions intended for coloring, such as ink compositions, printing pastes, and paints.

[0053] Storage Modulus The aqueous adhesive composition of the present embodiment is for forming an adhesive layer on the surface of a fabric transport member of an inkjet textile printing device. The adhesive layer obtained by the present embodiment has excellent adhesive strength and abrasion resistance.

[0054] The storage modulus of the adhesive layer of the present embodiment at 23° C. is preferably 1.4×10 5 ~5.0×10 5 Pa, 1.6 x 10 5 ~4.8×10 5 Pa, 2.0 x 10 5 ~4.5×10 5 The storage modulus is 1.5×10 Pa. 5 When the compressive strength is equal to or higher than Pa, the abrasion resistance tends to be further improved.

[0055] The method for forming the adhesive layer for measuring the storage modulus is not particularly limited. For example, the aqueous adhesive composition was applied to a 25 mm wide slide glass to a thickness of 0.2 mm at room temperature, and dried under conditions of a humidity of 50%, 23°C, and for 8 hours.

[0056] When an adhesive layer consisting only of a first (meth)acrylic resin (hereinafter referred to as a "first acrylic adhesive layer") is formed by the same method as in the case of the aqueous adhesive composition, the storage modulus of the first acrylic adhesive layer at 23°C is not particularly limited, but is preferably 3.0 × 10 5 That is 4.0 x 10 5 Above 5.0 x 10 5 That is 6.0 x 10 5 The storage modulus is preferably 9.0×10 5 Pa or less, 8.5×10 5 Pa or less, 8.0×10 5 When the storage modulus of the first acrylic adhesive layer is within the above range, the adhesive strength and abrasion resistance of the adhesive layer tend to be further improved.

[0057] 1.8. Adhesive strength The adhesive strength of the adhesive layer at 23° C. is preferably 0.3 N / 50 mm or more and 3.0 N / 50 mm or less, 0.5 N / 50 mm or more and 2.0 N / 50 mm or less, or 0.7 N / 50 mm or more and 1.8 N / 50 mm or less. The adhesive strength at 23° C. being within the above range indicates good adhesive strength of the adhesive layer.

[0058] 2. Method of adding adhesiveness The method for imparting tackiness of the present embodiment includes a step of adhering the aqueous pressure-sensitive adhesive composition to the surface of a fabric transport member of an inkjet textile printing apparatus to form a pressure-sensitive adhesive layer.

[0059] The step of forming the adhesive layer is a step of adhering the aqueous adhesive composition to the surface of the fabric transport member to form an adhesive layer. The method of adhering the aqueous adhesive composition to the fabric transport member is not particularly limited, but the aqueous adhesive composition may be applied uniformly to the entire surface of the fabric transport member using a blade or the like, or may be applied to a part of the surface of the fabric transport member in a predetermined pattern.

[0060] In the adhesive layer forming step, the aqueous adhesive composition may be dried to form the adhesive layer. The drying temperature is preferably 10 to 60° C., and more preferably 20 to 40° C. The drying time is preferably 1 to 24 hours, and more preferably 2 to 8 hours. This tends to further improve the water resistance and mechanical strength of the resulting adhesive layer, and further improve the abrasion resistance.

[0061] 3. Inkjet printing equipment The inkjet printing apparatus of this embodiment has a transport mechanism that transports a fabric by bonding it to an adhesive layer made of the above-mentioned aqueous adhesive composition formed on the surface of a fabric transport member, a recording unit that performs textile printing recording on the fabric attached to the adhesive layer using an inkjet head, and a cleaning unit that cleans the adhesive layer from which the fabric has been peeled off after textile printing recording.

[0062] An inkjet textile printing apparatus 100 of this embodiment will be described with reference to Fig. 1. Fig. 1 is an overall configuration diagram of the inkjet textile printing apparatus 100 including a transport device 200 of this embodiment. In Fig. 1, arrows a and b indicate the transport direction of a recording medium 300. Arrows c and d indicate the rotation direction of a fabric transport member 210. Arrows e and f indicate the rotation directions of transport rollers 221 and 222.

[0063] The inkjet printing apparatus 100 may include a conveying device 200 for attaching a recording medium to a surface and conveying it, recording medium conveying rollers 111 and 112, and a recording unit 120. A recording medium 300 coming from a direction a is pressed against a fabric conveying member 210 by the recording medium conveying roller 111, and the recording medium 300 is attached to the surface of the fabric conveying member 210.

[0064] With recording medium 300 attached to the surface of fabric transport member 210, transport device 200 transports recording medium 300 directly below recording unit 120, which then records on recording medium 300. Then, recording medium transport rollers 112 separate recording medium 300 from fabric transport member 210.

[0065] The recording unit 120 may eject an ink composition or the like by an inkjet method. In this embodiment, it is assumed that an inkjet head is used for the recording unit 120 and printing is performed on a textile fabric as the recording medium 300, but the present invention is not limited to this.

[0066] The conveying device 200 may include a pair of conveying rollers 221 and 222 , a fabric conveying member 210 , a drive motor 230 , a control device 240 , a cleaning unit 250 , and a removing member 260 .

[0067] The transport rollers 221 and 222 are rollers for transporting the fabric transport member 210 in a fixed direction. The fabric transport member 210 may be a belt member having an adhesive layer on its surface, and is provided around the transport rollers 221 and 222. The fabric transport member 210 transports the recording medium in the direction of arrow c as the transport rollers 221 and 222 are rotated by the drive motor 230. The control device 240 may control either the transport device 200 or the inkjet printing device 100, or both.

[0068] The cleaning unit 250 cleans the surface of the fabric transport member 210 that has been peeled off from the recording medium 300. The cleaning unit 250 cleans the components of the recording medium 300 and the printing colorant that have adhered to the fabric transport member 210 during printing. The cleaning unit 250 may include a pump (not shown), a water sprinkler port, and a water sprinkler pipe.

[0069] The removing member 260 removes water that has been attached to the fabric transport member 210 by the cleaning unit 250. The removing member 260 is not particularly limited, but may be, for example, a blade. The material of the blade is preferably an elastic material. Furthermore, polyurethane is preferable from the viewpoint of abrasion resistance. The contact portion with the fabric transport member 210 may have a rectangular cross section, or may have a shape with a diagonally cut-off tip.

[0070] An elastic material is preferable for the fabric transport member 210. A heater (not shown) may be provided to warm the fabric transport member 210. In the process of washing the fabric transport member 210, a water receiving section (not shown) for receiving washing water, a brush (not shown) for cleaning the fabric transport member 210, a sponge (not shown), etc. may be used.

[0071] The recording medium 300 may be a fabric made of natural or synthetic fibers such as silk, cotton, wool, nylon, polyester, rayon, etc. The fabric may be a woven fabric, a knitted fabric, a nonwoven fabric, or the like.

[0072] 4. Fabric transport member for inkjet printing device The fabric transport member of the inkjet printing device of this embodiment has an adhesive layer derived from the aqueous adhesive composition on the surface. The fabric transport member is not particularly limited, but is preferably made of an elastic material, particularly a urethane material. By using the aqueous adhesive composition containing a urethane resin and an acrylic resin in combination for such a fabric transport member, the adhesion between the adhesive layer and the fabric transport member is further improved, and the abrasion resistance is improved.

[0073] 5. Inkjet printing method The inkjet textile printing method includes a transporting step of attaching a fabric to an adhesive layer made of the aqueous adhesive composition formed on the surface of a fabric transporting member of an inkjet textile printing device and transporting the fabric, a recording step of performing textile printing recording on the fabric attached to the adhesive layer using an inkjet head, and a cleaning step of cleaning the adhesive layer from which the fabric has been peeled off after textile printing recording.

[0074] 5.1.Transportation process The conveying step is a step of laminating the fabric to the adhesive layer of the aqueous adhesive composition formed on the surface of the fabric conveying member of the inkjet printing device and conveying the fabric. The lamination method is not particularly limited, but may be a method of pressing the two together using a conveying roll as shown in FIG.

[0075] 5.2.Recording process The recording process is a process of performing a textile printing recording on the fabric attached to the adhesive layer using an inkjet head. In the recording process, the fabric transport member and the fabric are transported in a state of being in close contact with each other via the adhesive layer on the surface of the fabric transport member, and ink is ejected from the recording unit 120 and adhered to the fabric during the transport process. After that, the fabric with the ink adhered thereto may be peeled off from the adhesive layer and collected.

[0076] 5.3.Cleaning process The cleaning step is a step of cleaning the adhesive layer from which the fabric has been peeled off after the textile printing process, which makes it possible to remove dust such as lint and other debris from the fabric that has adhered during the recording step from the surface of the adhesive layer. EXAMPLES

[0077] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited to the following examples.

[0078] 1. Synthesis of (meth)acrylic resins A to I FIG. 2 shows Table 1 showing the compositions of (meth)acrylic resins A to I. 114 g of ion-exchanged water was added to a reactor equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube, and a dropping funnel, and the temperature was raised to 82°C. Then, a total of 498 g of monomers, 79 g of ion-exchanged water, and 34 g of Emulgen 123P (surfactant, product name, manufactured by Kao Corporation), which were weighed to have the composition ratios shown in Table 1 below, were added and mixed and stirred. 249 g of a 2% by mass aqueous solution of ammonium persulfate, which is a polymerization initiator, was added to the homogenized solution at 82°C over 1.5 hours. After adding all the above-mentioned ingredients, the mixture was kept warm for 1 hour and then cooled, and ion-exchanged water was added and the pH was adjusted to 8 to 9 with ammonia water. The mixture was filtered through a 150-mesh nylon filter to remove coarse particles, thereby obtaining aqueous dispersions of (meth)acrylic resins A to I shown in Table 1. In Table 1, "MMA" stands for "methyl methacrylate," "EMA" stands for "ethyl methacrylate," "PMA" stands for "n-propyl methacrylate," "St" stands for "styrene," "BMA" stands for "butyl methacrylate," "BA" stands for "butyl acrylate," and "2EHA" stands for "2-ethylhexyl acrylate," and the glass transition temperature Tg (°C) of each homopolymer is shown below the item. The amount of each homopolymer used in the table is shown in mass %, with the solid content being the component amount.

[0079] 2. Preparation of the aqueous adhesive composition FIG. 3 shows Table 2 showing the composition of the aqueous pressure sensitive adhesive composition. First, the aqueous dispersions of the (meth)acrylic resins A to I obtained above were mixed in a combination of the following components 1 and 2. Then, the components 1 and 2 (meth)acrylic resins were mixed in a tank for mixing so that the total amount of the (meth)acrylic resins was 47.8% by mass (total amount calculated as solid content), water was 48.7% by mass, and Emulgen 123P (surfactant, trade name, manufactured by Kao Corporation) was 3.5% by mass (total 100% by mass), and the components were mixed and stirred to obtain an aqueous pressure-sensitive adhesive composition. The types and component ratios of the (meth)acrylic resins used, the measured glass transition temperatures Tg (°C) of each resin, and the evaluation results of the storage modulus, adhesive strength, and abrasion resistance of the obtained aqueous pressure-sensitive adhesive composition are shown in Table 2. In Example 9, the (meth)acrylic resin J was used alone, and the glass transition temperatures Tg of each component were measured by differential scanning calorimetry (DSC) in accordance with JIS K7121.

[0080] 3. Measurement and evaluation methods 3.1.Storage modulus The resin of component 1 of each example in Table 2 and the obtained aqueous adhesive composition were applied to a 25 mm wide slide glass in a thickness of 0.2 mm, and dried under conditions of 50% humidity, 23°C, and 8 hours to obtain an adhesive layer. The storage modulus of the adhesive layer at 23°C was measured using the following viscoelasticity measuring device. The measurement sample was cut to 1 cm x 1 cm. Equipment: MCR302 (Anton Parr) Jig: 8mm parallel plate Gap range: 0.6~1.0mm Frequency: 1.0Hz Distortion rate: 0.2% Temperature: 23℃

[0081] 3.2. Adhesive strength The aqueous adhesive composition obtained above was applied to a 25 mm wide slide glass to a thickness of 0.2 mm, and dried under conditions of 25% humidity, 50°C, and 30 minutes to form an adhesive layer, which was then roller-pressed to a 50 mm wide cotton strip at a pressure of 1 kgf / 50 mm, and the 180° peel strength was measured. The measurement was performed at 23°C. (Evaluation Criteria) 〇: 1.0N / 50mm or more, less than 2.0N / 50mm △: 0.5N / 50mm or more, less than 1.0N / 50mm ×: Less than 0.5N / 50mm

[0082] 3.3.Abrasion Resistance A water-soaked nylon brush was rotated at 200 rpm and pressed against the adhesive layer formed above with a pressure of 1.0 N / cm, and the surface of the adhesive layer was visually inspected after 200 hours to determine the quality. The nylon brush used was made of 6·10 nylon, with bristles of 0.3 mm diameter, 30 mm long, and 16 mm in diameter. (Evaluation Criteria) 〇: No scratches △: Slightly scratched ×: Unevenness is observed

[0083] 4. Evaluation Results The composition and evaluation results of the aqueous adhesive composition used in each example are shown in Table 2. From Table 2, it can be seen that when the aqueous adhesive composition for forming an adhesive layer on the surface of a fabric transport member of an inkjet printing device contains a (meth)acrylic resin and water, the (meth)acrylic resin contains a first (meth)acrylic resin and a second (meth)acrylic resin having a glass transition temperature Tg2 lower than the glass transition temperature Tg1 of the first (meth)acrylic resin, the first (meth)acrylic resin contains methyl methacrylate or ethyl methacrylate as a constituent unit, and the total content of the methyl methacrylate and the ethyl methacrylate is 10% by mass or more and 41% by mass or less with respect to the entirety of the constituent units of the first (meth)acrylic resin, the resulting adhesive layer has excellent adhesion and abrasion resistance. [Explanation of symbols]

[0084] 100... inkjet printing apparatus, 111, 112... recording medium transport rollers, 120... recording unit, 200... transport device, 210... fabric transport member, 221, 222... transport rollers, 230... drive motor, 240... control device, 250... cleaning unit, 260... removal member, 300... recording medium.

Claims

1. An aqueous adhesive composition for forming an adhesive layer on a surface of a fabric transport member of an inkjet textile printing device, comprising: (Meth)acrylic resin and water, the (meth)acrylic resin includes a first (meth)acrylic resin and a second (meth)acrylic resin having a glass transition temperature Tg2 lower than a glass transition temperature Tg1 of the first (meth)acrylic resin, The first (meth)acrylic resin contains methyl methacrylate or ethyl methacrylate as a structural unit, The total content of the methyl methacrylate and the ethyl methacrylate is 10% by mass or more and 41% by mass or less with respect to the total amount of the structural units of the first (meth)acrylic resin. Aqueous pressure sensitive adhesive composition.

2. The content of the first (meth)acrylic resin is 50% by mass or more and 82% by mass or less with respect to the total amount of the first (meth)acrylic resin and the second (meth)acrylic resin. The aqueous pressure-sensitive adhesive composition according to claim 1 .

3. The layer formed of the first (meth)acrylic resin has a storage modulus at 23° C. of 4.0×10 ５ Pa or more. The aqueous pressure-sensitive adhesive composition according to claim 1 .

4. a total content of the compounds selected from the group consisting of rosin-based compounds, terpene-based compounds, and hydrocarbon resins is 5 mass% or less based on the total amount of the aqueous pressure-sensitive adhesive composition; The aqueous pressure-sensitive adhesive composition according to claim 1 .

5. The adhesive strength of the adhesive layer at 23°C is 0.5 N / 50 mm or more and 2.0 N / 50 mm or less. The aqueous pressure-sensitive adhesive composition according to claim 1 .

6. The content of the organic solvent is 5.0 mass% or less based on the total amount of the aqueous pressure-sensitive adhesive composition. The aqueous pressure-sensitive adhesive composition according to claim 1 .

7. The content of the coloring material is 1.0 mass% or less based on the total amount of the aqueous pressure-sensitive adhesive composition. The aqueous pressure-sensitive adhesive composition according to claim 1 .

8. The method includes a step of applying the aqueous pressure-sensitive adhesive composition according to any one of claims 1 to 7 to a surface of a fabric transport member of an ink-jet printing apparatus to form an adhesive layer. Method of imparting adhesion.

9. A conveying mechanism that conveys a fabric by laminating the fabric to the adhesive layer made of the aqueous pressure-sensitive adhesive composition according to any one of claims 1 to 7, the adhesive layer being formed on a surface of a fabric-conveying member; a recording unit that performs printing recording on the fabric attached to the adhesive layer using an inkjet head; and a cleaning unit that cleans the adhesive layer from which the fabric has been peeled off after the textile printing. Inkjet textile printing device.

10. A pressure-sensitive adhesive layer comprising the aqueous pressure-sensitive adhesive composition according to any one of claims 1 to 7 on a surface thereof. A fabric transport member for an ink-jet printing device.

11. A transporting step of laminating a fabric to the adhesive layer made of the aqueous adhesive composition according to any one of claims 1 to 7, which is formed on a surface of a fabric transporting member of an inkjet printing apparatus, and transporting the fabric; a recording step of performing a textile printing recording on the fabric attached to the adhesive layer using an inkjet head; and a cleaning step of cleaning the adhesive layer from which the fabric has been peeled off after the textile printing. Inkjet printing method.

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