Aqueous adhesive composition

Abstract

To provide an aqueous adhesive composition that can form an adhesive layer that can be peeled off with an aqueous solvent.SOLUTION: There is provided an aqueous adhesive composition for forming an adhesive layer at a surface of a fabric transport member of an ink jet textile printing apparatus, the aqueous adhesive composition including: a (meth)acrylic resin; and water, in which the (meth)acrylic resin includes a constituent unit having an alkylene oxide chain of which the number of repetitions is 10 or more at a side chain, and an acid value of the (meth)acrylic resin is more than 0 mgKOH / g.SELECTED DRAWING: Figure 1

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-resolution images with a relatively simple device, and have been rapidly developing in various fields. In the process, various studies have been conducted on ejection stability, etc. For example, Patent Document 1 discloses a conveying device including: a conveying member that carries a recording medium while rotating in a predetermined direction; a cleaning device that cleans the recording medium-carrying surface of the conveying member with a cleaning liquid; a removal member that contacts the conveying member to remove the cleaning liquid on the conveying member; and a displacement suppression member that suppresses displacement of the conveying member in a direction intersecting the movement direction of the conveying member when the conveying member rotates. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2020-109036 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, in a conventional inkjet textile printing device, an adhesive layer is formed on a transport member such as an endless belt, a fabric serving as a recording medium is attached to the adhesive layer, the fabric is transported to a printing unit, recording is performed, and then the transport member and fabric are peeled off to perform printing. An adhesive layer for the fabric transport member is formed on the surface of such a transport member, and the transport member has an adhesive surface.

[0005] After the fabric is peeled off, ink, lint, and other residues that adhered to the conveying member during the printing process remain on the conveying member. Therefore, these residues must be removed before the fabric is reattached. Typically, ink, lint, and other residues adhering to the conveying member are washed away with water. In this process, a brush, sponge, or other cleaning tool may be used to clean the conveying member.

[0006] The adhesive layer used in such inkjet printing is generally made of a hydrophobic resin dissolved in an organic solvent so as to be resistant to washing with water. However, in order to reduce the environmental load and improve the working environment, there is a demand for an aqueous adhesive composition for forming the adhesive layer, which uses a reduced amount of organic solvent. [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 textile printing device, and comprises a (meth)acrylic resin and water, wherein the (meth)acrylic resin comprises a structural unit having an alkylene oxide chain with a repeating number of 10 or more in a side chain, and the acid value of the (meth)acrylic resin exceeds 0 mgKOH / g.

[0008] The method for imparting tackiness of the present invention comprises a step of adhering the aqueous adhesive composition to the surface of a fabric transport member of an inkjet textile printing device to form an adhesive layer.

[0009] The inkjet textile printing device of the present invention includes a conveying mechanism that conveys a fabric by adhering it to an adhesive layer made of the above-mentioned aqueous adhesive composition formed on the surface of a fabric conveying member, a recording unit that performs textile printing recording on the fabric adhered 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 recording.

[0010] The fabric transport member of the ink-jet printing device of the present invention has an adhesive layer derived from the aqueous adhesive composition on its surface.

[0011] 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 explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic cross-sectional view of an inkjet textile printing apparatus. [Figure 2] 1 is a table showing examples and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0013] 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 spirit of the present invention. In the drawings, the same elements are given the same reference numerals, and redundant explanations will be omitted. Furthermore, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0014] The term "(meth)acrylate" is a comprehensive expression that encompasses acrylate and methacrylate. The term "unit" as used herein, such as "structural unit" or "(meth)acrylate unit," refers to a repeating unit derived from a monomer when the monomer is polymerized to form a polymer.

[0015] 1. Water-based adhesive composition The aqueous adhesive composition according to this embodiment is an aqueous adhesive composition for forming an adhesive layer on the surface of a fabric transport member of an inkjet textile printing device, and comprises a (meth)acrylic resin and water, wherein the (meth)acrylic resin comprises a structural unit having an alkylene oxide chain with a repeat number of 10 or more in a side chain, and the acid value of the (meth)acrylic resin exceeds 0 mgKOH / g.

[0016] The aqueous pressure-sensitive adhesive composition of the present embodiment has the above-described configuration, and is therefore capable of forming a pressure-sensitive adhesive layer that can be peeled off with an aqueous solvent. Each component contained in the aqueous pressure-sensitive adhesive composition will be described in detail below.

[0017] 1.1.(Meth)acrylic resin The (meth)acrylic resin contains a structural unit having an alkylene oxide chain with a repeat number of 10 or more in the side chain, and has an acid value of more than 0 mgKOH / g. By containing such a (meth)acrylic resin, the peelability of the formed adhesive layer tends to be further improved.

[0018] The (meth)acrylic resin may be a water-soluble resin or a resin emulsion dispersed in an aqueous solvent. These are collectively referred to as (meth)acrylic resin in the present embodiment. Furthermore, the (meth)acrylic resin may be a copolymer of an allyl monomer in addition to a (meth)acrylate. The use of a (meth)acrylic resin can reduce the environmental burden caused by organic solvents, and also tends to further improve the peelability of the fabric in the adhesive layer.

[0019] The glass transition temperature of the (meth)acrylic resin is preferably −35 to 5° C., −30 to 0° C., −25 to −5° C., −20 to −5° C., or −15 to −7.5° C. When the glass transition temperature of the (meth)acrylic resin is within the above range, the adhesive strength of the obtained adhesive layer tends to be further improved.

[0020] In the present embodiment, the glass transition temperature can be measured by a conventionally known method such as differential scanning calorimetry (DSC). The glass transition temperature of the (meth)acrylic resin can be adjusted by the homopolymer glass transition temperature of the polymerizable compound used and the mass ratio of the polymerizable compound used.

[0021] The acid value of the (meth)acrylic resin exceeds 0 mgKOH / g, preferably 1.0 to 30 mgKOH / g, 2.0 to 25 mgKOH / g, 2.0 to 20 mgKOH / g, 2.0 to 10 mgKOH / g, or 5.0 to 10 mgKOH / g. When the acid value of the (meth)acrylic resin exceeds 0 mgKOH / g, the peelability of the resulting adhesive layer tends to be further improved.

[0022] The acid value of the (meth)acrylic resin can be adjusted by the content of a monomer having an acidic group such as a carboxyl group.

[0023] The (meth)acrylic resin is preferably a resin emulsion, and its average particle size is preferably 25 to 500 nm, 50 to 400, 75 to 300, 100 to 250 nm, or 125 to 200 nm. When the average particle size of the (meth)acrylic resin is within the above range, dispersion stability is further improved, and the releasability of the resulting adhesive layer tends to be further improved.

[0024] The (meth)acrylic resin contains, as a structural unit, a structural unit having an alkylene oxide chain with a repeating number of 10 or more in the side chain, and may contain a structural unit derived from an alkyl acrylate having an alkyl group, a structural unit derived from an aromatic acrylate having an aromatic group, or a structural unit derived from (meth)acrylic acid having a carboxyl group.

[0025] The monomer that constitutes the structural unit having an alkylene oxide chain with a repeat number of 10 or more in the side chain is not particularly limited, but examples include (meth)acrylates having an alkylene oxide chain with a repeat number of 10 or more in the side chain, and allyl monomers having an alkylene oxide chain with a repeat number of 10 or more in the side chain.

[0026] The alkylene oxide chain is not particularly limited, and may, for example, contain repeating units of ethylene oxide, propylene oxide, or both ethylene oxide and propylene oxide. Furthermore, the repeating number n of the alkylene oxide chain is 10 or more, preferably 10 to 40, 10 to 30, or 20 to 30. When the repeating number n is within the above range, the releasability of the resulting adhesive layer tends to be further improved.

[0027] The content of the structural units having an alkylene oxide chain is preferably 0.1 to 10 mass%, 0.3 to 7.5 mass%, or 0.5 to 5.0 mass%, based on the total amount of structural units of the (meth)acrylic resin. When the content of the structural units having an alkylene oxide chain is within the above range, the releasability of the resulting adhesive layer tends to be further improved.

[0028] The monomer constituting the structural unit derived from an alkyl acrylate having an alkyl group is not particularly limited, but examples thereof include methyl methacrylate (MMA), ethyl methacrylate (EMA), butyl methacrylate (BMA), butyl acrylate (BA), and 2-ethylhexyl acrylate (2EHA).

[0029] The content of the structural units derived from alkyl acrylate having an alkyl group, relative to all structural units of the (meth)acrylic resin, is preferably 65 to 99.9 mass%, 70 to 99.8 mass%, 75 to 99.7 mass%, 80 to 99.6 mass%, 90 to 99.5 mass%, or 90 to 97 mass%. When the content of the structural units derived from alkyl acrylate having an alkyl group is within the above range, the wash resistance and easy peelability of the obtained adhesive layer tend to be further improved.

[0030] The structural unit derived from an aromatic acrylate having an aromatic group is not particularly limited, but examples thereof include styrene (St).

[0031] The content of the structural units derived from aromatic acrylate is preferably 0 to 30 mass%, 0 to 25 mass%, or 5 to 20 mass%, relative to the total structural units of the (meth)acrylic resin, which tends to further improve the washing resistance of the resulting adhesive layer.

[0032] The structural unit derived from (meth)acrylic acid having a carboxyl group is not particularly limited, but examples thereof include acrylic acid (AA) and methacrylic acid (MA).

[0033] The content of the structural units derived from (meth)acrylic acid is preferably 0.1 to 3.0 mass%, 0.3 to 2.5 mass%, or 0.5 to 2.0 mass%, relative to the total amount of the (meth)acrylic resin. When the content of the structural units derived from (meth)acrylic acid is within the above range, the peelability, adhesiveness, and washing resistance of the resulting adhesive layer tend to be further improved.

[0034] The content of the (meth)acrylic resin is preferably 30 to 70 mass%, 35 to 65 mass%, 40 to 60 mass%, or 45 to 55 mass%, relative to the total amount of the aqueous pressure-sensitive adhesive composition. When the content of the (meth)acrylic resin is within the above range, the resulting pressure-sensitive adhesive layer tends to have improved releasability, adhesiveness, and washing resistance, as well as improved dispersion stability. The content relative to the total amount of the aqueous pressure-sensitive adhesive composition refers to the amount of solids.

[0035] 1.2. pH adjusters The pH adjuster is not particularly limited, but examples thereof include inorganic acids (e.g., sulfuric acid, hydrochloric acid, nitric acid, etc.), inorganic bases (e.g., lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonia, ammonium salts, etc.), organic bases (triethanolamine, diethanolamine, monoethanolamine, tripropanolamine), and organic acids (e.g., adipic acid, citric acid, succinic acid, etc.).

[0036] Among these, ammonia or ammonium salts are preferred. By using such a pH adjuster, ammonia volatilizes when forming the adhesive layer, and the (meth)acrylic resins become more easily adhered to each other, forming a coating film that is less susceptible to water penetration. As a result, the adhesive layer formed on the fabric conveying member has improved adhesive strength durability and water resistance, and the adhesiveness tends to be maintained over a wide temperature range.

[0037] The content of the pH adjuster is preferably 0.05 to 1.50 mass%, 0.10 to 1.00 mass%, 0.15 to 0.50 mass%, or 0.20 to 0.30 mass%, relative to the total amount of the aqueous pressure-sensitive adhesive composition. The pH adjuster may be contained so that the pH of the aqueous pressure-sensitive adhesive composition is 7.7 to 9.0, or 8.0 to 8.7. When the content of the pH adjuster is within the above range, the peelability, adhesiveness, and washing resistance of the resulting pressure-sensitive adhesive layer are further improved, and dispersion stability also tends to be further improved.

[0038] 1.3.Water The water content is preferably 30 to 80 mass %, 35 to 70 mass %, or 40 to 60 mass %, relative to the total amount of the aqueous pressure-sensitive adhesive composition.

[0039] 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.

[0040] Examples of anionic surfactants include alkyl sulfocarboxylates, alkyl diphenyl ether disulfonates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acylamino acids and salts thereof, N-acylmethyl 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 esters, lauryl alcohol sulfate esters, alkylphenol phosphate esters, alkyl phosphate esters, alkylaryl sulfonates, diethyl sulfosuccinates, diethylhexyl cyrsulfosuccinates, and dioctyl sulfosuccinates.

[0041] Examples of nonionic surfactants include acetylene glycol surfactants, silicone surfactants, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene hydrogenated 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 alkyl amine oxides.

[0042] 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.

[0043] In this embodiment, among these, nonionic surfactants are preferred, and more specifically, alkyl ether-based nonionic surfactants are preferred. Use of such surfactants tends to maintain durability and water resistance.

[0044] The content of the surfactant is preferably 0.1 to 5 mass %, 0.2 to 4 mass %, or 0.3 to 3 mass %, relative to the total amount of the aqueous pressure-sensitive adhesive composition.

[0045] 1.5. Tackifiers The aqueous pressure-sensitive adhesive composition preferably contains no or a small amount of a tackifier. When the aqueous pressure-sensitive adhesive composition contains no or a small amount of a tackifier, the adhesive strength of the adhesive layer and the effect of suppressing the decrease in adhesive strength during brushing tend to be more sustained. Typical examples of such tackifiers include rosin-based compounds, terpene-based compounds, and hydrocarbon resins. More specifically, examples of the compound include rosin-based compounds such as natural rosin, modified rosin, glycerol esters of natural rosin, glycerol esters of modified rosin, pentaerythritol esters of natural rosin, and pentaerythritol esters 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 phenol resins, and terpene resins (monoterpene, diterpene, triterpene, polyperene, etc.); and hydrocarbon resins such as aliphatic petroleum hydrocarbon resins (C5 resins), hydrogenated derivatives of aliphatic petroleum hydrocarbon resins, aromatic petroleum hydrocarbon resins (C9 resins) such as styrene oligomers, and hydrogenated derivatives of aromatic petroleum hydrocarbon resins.

[0046] It is preferable that the composition does not contain a tackifier. However, if a tackifier is contained, the content thereof 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 pressure-sensitive adhesive composition. When the content of the tackifier is within the above range, the adhesive strength of the resulting adhesive layer and the effect of suppressing a decrease in adhesive strength during brushing tend to be more sustained. From the same viewpoint, the total content of compounds selected from the group consisting of rosin-based compounds, terpene-based compounds, and hydrocarbon resins is also preferably within the same range.

[0047] 1.6. Organic Solvents From the viewpoint of reducing the environmental load and the influence on the human body, the aqueous pressure-sensitive adhesive composition of the present embodiment preferably does not contain an organic solvent. Furthermore, when an organic solvent is contained, the content of the organic solvent is preferably 5.0 mass % or less, 2.5 mass % or less, or 1.0 mass % or less, based on the total amount of the aqueous pressure-sensitive adhesive composition. This reduces the environmental load and VOCs (volatile organic compounds) when the aqueous pressure-sensitive adhesive composition is used, which tends to further improve the working environment.

[0048] 1.7.Colorants The aqueous pressure-sensitive adhesive composition of this embodiment preferably does not contain a colorant. Furthermore, if a colorant is contained, the content of the colorant 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 pressure-sensitive adhesive composition. This clearly distinguishes the aqueous pressure-sensitive adhesive composition of this embodiment from compositions intended for coloring ink compositions, textile printing pastes, paints, and the like.

[0049] 2.Method of providing adhesiveness The method for imparting tackiness of this 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 device to form a pressure-sensitive adhesive layer.

[0050] The step of forming the adhesive layer is a step of applying the aqueous adhesive composition to the surface of the fabric conveying member to form an adhesive layer. The method of applying the aqueous adhesive composition to the fabric conveying member is not particularly limited, but the aqueous adhesive composition may be applied uniformly to the entire surface of the fabric conveying member using a blade or the like, or may be applied to a part of the surface of the fabric conveying member in a predetermined pattern.

[0051] 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.

[0052] 3. Inkjet printing equipment The inkjet printing device of this embodiment has a conveying mechanism that attaches a fabric to an adhesive layer made of the above-mentioned aqueous adhesive composition formed on the surface of a fabric conveying member and conveys the fabric, 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.

[0053] An inkjet textile printing apparatus 100 of this embodiment will be described with reference to Figure 1. Figure 1 is an overall configuration diagram of the inkjet textile printing apparatus 100 including a conveying device 200 of this embodiment. In Figure 1, arrows a and b indicate the conveying direction of the recording medium 300. Arrows c and d indicate the rotation direction of the fabric conveying member 210. Arrows e and f indicate the rotation direction of the conveying rollers 221 and 222.

[0054] The inkjet printing apparatus 100 may have 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 the 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.

[0055] With the recording medium 300 stuck to the surface of the fabric conveying member 210, the conveying device 200 conveys the recording medium 300 directly below the recording unit 120, and the recording unit 120 records on the recording medium 300. Then, the recording medium conveying roller 112 separates the recording medium 300 from the fabric conveying member 210.

[0056] 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 that printing is performed on a textile fabric as the recording medium 300, but the present invention is not limited to this.

[0057] 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 , a removing member 260 , and a heater 270 .

[0058] The transport rollers 221 and 222 are rollers for transporting the fabric transport member 210 in a certain 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 a drive motor 230. The control device 240 may control either or both of the transport device 200 and the inkjet printing device 100.

[0059] The cleaning unit 250 cleans the surface of the fabric transport member 210 that has been separated 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.

[0060] The removing member 260 removes water that has adhered to the fabric conveying 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 conveying member 210 may have a rectangular cross section, or may have a shape with an obliquely cut-off tip.

[0061] The heater 270 may be provided downstream of the cleaning unit 250 and upstream of the recording medium conveying roller 111 that performs the laminating step. When the adhesive layer is heated by the heater 270, the (meth)acrylic resin that constitutes the adhesive layer softens, and the adhesive strength tends to be further improved.

[0062] An elastic material is preferable for the fabric conveying member 210. A heater (not shown) may be installed to warm the fabric conveying member 210. In the process of washing the fabric conveying member 210, a water receiving section (not shown) for receiving washing water, a brush (not shown) for cleaning the fabric conveying member 210, a sponge (not shown), etc. may be used.

[0063] 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 also be woven, knitted, or nonwoven.

[0064] 4. Fabric transport member for inkjet printing equipment The fabric transporting member of the inkjet printing device of this embodiment has an adhesive layer derived from the aqueous adhesive composition on its surface. The fabric transporting member is not particularly limited, but is preferably made of, for example, an elastic material, and particularly preferably contains a urethane resin. By using the aqueous adhesive composition described above for such a fabric transporting member, the adhesion between the adhesive layer and the fabric transporting member is further improved, and water resistance is improved.

[0065] 5. Inkjet printing method The inkjet textile printing method includes a conveying step of adhering a fabric to an adhesive layer made of the aqueous adhesive composition formed on the surface of a fabric conveying member of an inkjet textile printing device and conveying the fabric; a recording step of performing textile printing recording on the fabric adhered 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.

[0066] 5.1.Transportation process The conveying step is a step of laminating a fabric to the adhesive layer of the aqueous adhesive composition formed on the surface of a fabric conveying member of an inkjet textile printing device and conveying the fabric. The laminating method is not particularly limited, but examples thereof include a method of laminating the two by pressing them together using a conveying roll, as shown in Figure 1.

[0067] 5.2. Recording process The recording process is a process in which textile printing is performed using an inkjet head on the fabric attached to the adhesive layer. During the recording process, the fabric is transported in a state in which it is in close contact with the fabric transport member via the adhesive layer on the surface of the fabric transport member, and during this transport process, ink is ejected from the recording unit 120 and adhered to the fabric. After this, the fabric with the ink adhered thereto may be peeled off from the adhesive layer and collected.

[0068] 5.3.Cleaning process The cleaning step is a step of cleaning the adhesive layer from which the fabric has been peeled off after textile printing. This step makes it possible to remove lint and other debris from the adhesive layer surface that has adhered to the adhesive layer during the printing step. [Example]

[0069] 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.

[0070] 1. Preparation of aqueous adhesive composition 114 g of ion-exchanged water was added to a reactor equipped with a stirrer, reflux condenser, thermometer, nitrogen inlet tube, and dropping funnel, and the temperature was raised to 82°C. Then, a total of 497 g of monomers weighed to have the composition ratio shown in Figure 2, 118 g of ion-exchanged water, and 13 g of Hitenol NF-08 (polyoxyethylene styrenated phenyl ether ammonium sulfate, nonionic surfactant, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) were added and mixed with stirring. 248 g of a 2% by mass aqueous solution of ammonium persulfate, a polymerization initiator, was added to the homogenized solution at 82°C over 1.5 hours.

[0071] After adding all the ingredients listed above, the mixture was kept warm for 1 hour and then cooled. Ion-exchanged water was added, and aqueous ammonia was added as a pH adjuster. The mixture was then filtered through a 150-mesh nylon filter to remove coarse particles, yielding an aqueous pressure-sensitive adhesive composition (solid content 50.5% by mass) containing a (meth)acrylic resin with the composition shown in Figure 2. The amount of each monomer used in Figure 2 is shown in mass %.

[0072] 1.1.Monomer The monomers relating to the structural units of the (meth)acrylic resin shown in FIG. 2 are as follows: MMA: Methyl methacrylate EMA: Ethyl methacrylate St: styrene BMA: Butyl methacrylate BA: Butyl acrylate 2EHA: 2-ethylhexyl acrylate AA: acrylic acid MPMA2: Methoxypolyalkylene glycol methacrylate n=2 MPMA13: Methoxypolyalkylene glycol methacrylate n=13 MPMA45: Methoxypolyalkylene glycol methacrylate n=45 POS10: Polyoxyethylene alkyl ether sulfate ammonium salt n=10, X=SO3NH4 AOE30: Allyloxymethylalkoxyethylhydroxypolyoxyethylene n=30, X=H AOE40: Allyloxymethylalkoxyethylhydroxypolyoxyethylene n=40, X=H

[0073] The number n in MPMA2, ​​MPMA13, and MPMA45 means the number of repetitions n in the following chemical formula. CH2=C(CH3)C(=O)O(OCH2CH2) n OCH3

[0074] Furthermore, the number n in POS10, AOE30, and AOE40 means the number of repeats n in the following chemical formula, and the functional group X means X in the following chemical formula: CH2=CH2CHOCH2C(CH2OCH3)HO(CH2CH2O) n X

[0075] 1.2.Measurement method The average particle size is shown as the D50 value obtained by measurement using a zeta potential / particle size measurement system "ELSZ-1000ZS" (manufactured by Otsuka Electronics Co., Ltd.).

[0076] The acid value was measured in accordance with JIS K2501.

[0077] The glass transition temperature Tg was measured in accordance with JIS K7121 using a differential scanning calorimeter "DSC8000" (manufactured by Perkin Elmer), and the values ​​shown were obtained by measurement.

[0078] 2. Evaluation Method 2.1.Easy peelability The aqueous adhesive composition obtained as described above was applied to a urethane belt to a thickness of 0.2 mm and dried at 25% humidity, 50°C, and 30 minutes to form an adhesive layer. The adhesive layer was then immersed in water, and the peeling state from the belt was checked after 1 hour. Depending on the peeling state, the ease of peeling was evaluated according to the following evaluation criteria. (Evaluation criteria) A: Peels off cleanly B: It takes a little time, but it peels off C: Does not peel off cleanly

[0079] 2.2. Fabric transport adhesive strength The aqueous adhesive composition obtained as described above was applied to a 25 mm wide glass slide to a thickness of 0.2 mm and dried at 25% humidity and 50°C for 30 minutes to form an adhesive layer. The adhesive layer was then pressed onto a 50 mm wide piece of cotton using a roller at a pressure of 1 kgf / 50 mm, and the 180° peel strength was measured. The fabric transport adhesive strength was evaluated based on the 180° peel strength according to the following criteria. The measurements were performed at 23°C. (Evaluation criteria) A:1.0N / 50mm or more B: 0.2N / 50mm or more, less than 1.0N / 50mm C: Less than 0.2N / 50mm

[0080] 2.3.Water washing durability A water-soaked nylon brush was rotated at 200 rpm and pressed against the adhesive layer formed in the fabric transport adhesive strength evaluation above with a pressure of 1.0 N / cm, and the surface of the adhesive layer was visually inspected after 200 hours. Based on the results of this visual inspection, water washing durability was evaluated according to the following evaluation criteria. The nylon brush used was made of 6-10 nylon, with bristles of 0.3 mm diameter, 30 mm long, and a brush diameter of 16 mm. (Evaluation criteria) A: No scratches B: Slightly scratched C: Unevenness is visible

[0081] 2.4. Water dispersion stability 100 g of the aqueous PSA composition was placed in a 200 mL glass bottle and allowed to stand at 60° C. for 2 weeks, after which the state of the aqueous PSA composition in the glass bottle was visually inspected. Based on the results of the visual inspection, the aqueous dispersion stability was evaluated according to the following evaluation criteria. (Evaluation criteria) A: No thickening or aggregation C: Viscosity and aggregation

[0082] 3. Evaluation Results The composition and evaluation results of the aqueous adhesive composition used in each example are shown in Figure 2. It can be seen from Figure 2 that by including a specific (meth)acrylic resin in the aqueous adhesive composition for forming an adhesive layer on the surface of a fabric transport member of an inkjet textile printing device, the adhesive layer formed on the fabric transport member not only has excellent peelability, but also has improved wash resistance, adhesive strength, and dispersion stability. [Explanation of symbols]

[0083] 100...inkjet printing device, 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, 270...heater, 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 contains a structural unit having an alkylene oxide chain with a repeating number of 10 or more in a side chain, The acid value of the (meth)acrylic resin is greater than 0 mgKOH / g. Aqueous pressure-sensitive adhesive compositions.

2. The (meth)acrylic resin has a glass transition temperature of −25 to −5° C. The aqueous pressure-sensitive adhesive composition according to claim 1 .

3. The acid value of the (meth)acrylic resin is 2.0 to 10 mgKOH / g. The aqueous pressure-sensitive adhesive composition according to claim 1 .

4. the content of the structural unit having an alkylene oxide chain is 0.5 to 5.0 mass% based on the total amount of structural units of the (meth)acrylic resin; The aqueous pressure-sensitive adhesive composition according to claim 1 .

5. The (meth)acrylic resin has an average particle size of 100 to 250 nm. The aqueous pressure-sensitive adhesive composition according to claim 1 .

6. A method for imparting tackiness, comprising the step of applying the aqueous pressure-sensitive adhesive composition according to any one of claims 1 to 5 to a surface of a fabric transport member of an inkjet textile printing device to form a pressure-sensitive adhesive layer.

7. a conveying mechanism for conveying a fabric by adhering the fabric to an adhesive layer made of the aqueous pressure-sensitive adhesive composition according to any one of claims 1 to 5, which is formed on a surface of a fabric conveying member; a recording unit that performs textile printing recording on the fabric attached to the adhesive layer using an inkjet head; a cleaning section that cleans the adhesive layer from which the fabric has been peeled off after the textile printing recording.

8. A fabric transport member for an inkjet textile printing device, having an adhesive layer made from the aqueous adhesive composition according to any one of claims 1 to 5 on a surface thereof.

9. a conveying step of attaching a fabric to an adhesive layer made of the aqueous adhesive composition according to any one of claims 1 to 5, which is formed on a surface of a fabric conveying member of an inkjet textile printing device, and conveying the fabric; a recording step of performing textile printing 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.

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