Sized textile product, sizing agent, method for manufacturing sized textile product, and method for manufacturing textile product

Abstract

To provide a paste coated fiber product suitable for desizing using supercritical carbon dioxide.SOLUTION: A paste coated fiber product is one in which the paste includes alkenyl succinate ester of starch hydrolysate.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a sized textile product, a sizing agent, a method for producing a sized textile product, and a method for producing a textile product. [Background technology]

[0002] Generally, woven fabrics, such as cotton products, are made by interlacing warp and weft threads. Therefore, the process of making woven fabric begins with separating the raw warp and weft threads. The separated raw warp and weft threads then undergo various processes. Finally, they are woven on a loom, and the finished fabric is inspected and sent to the finishing process. The main processes in cotton product manufacturing are spinning, sizing, weaving, desizing, scouring, bleaching, dyeing, and finishing. Among these processes, sizing, desizing, scouring, and dyeing consume large amounts of water and also produce large amounts of wastewater. It is estimated that wastewater generated during clothing manufacturing accounts for 20% of the world's total wastewater. As reducing environmental impacts becomes a major global issue, environmentally friendly manufacturing processes that address these wastewater issues are needed. Among the above processes, the desizing process after weaving has a significant impact on the subsequent dyeing and finishing processes, product quality, etc. Conventional sizing agents that are the target of treatment in this desizing process are designed on the assumption that desizing will be performed using water.

[0003] Supercritical carbon dioxide is also known to be used in textile processing. The supercritical state occurs when a compound exceeds its specific critical temperature (Tc) and critical pressure (Tp). This state, called a supercritical fluid, has properties intermediate between those of a gas and a liquid. As shown in Figure 1, carbon dioxide can reach a supercritical state under relatively mild conditions: Tc is 31.1°C and Tp is 7.38 MPa. It has the advantages of being non-explosive, non-toxic, highly safe, inexpensive, and readily available. Furthermore, supercritical carbon dioxide has the following characteristics: (1) its density fluctuates significantly with small changes in pressure near its critical temperature; (2) its low viscosity and high diffusivity give it excellent transport properties and high penetration into materials; (3) its high thermal conductivity allows for rapid heat transfer; (4) its solvation effect allows for rapid reaction rates; (5) its dielectric constant is lower than that of water, making it comparable to that of conventional nonpolar organic solvents, making it a good solvent for nonpolar organic substances; and (5) the carbon dioxide can be recovered and reused. Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors believed that by using supercritical carbon dioxide as a solvent in place of the water conventionally used in the desizing process of textiles, it would be possible to realize an environmentally friendly textile manufacturing process that would solve the wastewater problem. The conventional sizing agent to be treated in the desizing process has traditionally been a starch-containing sizing agent. However, after extensive research, the present inventors found that starch-containing sizing agents are not suitable for desizing using supercritical carbon dioxide, since they are designed for desizing using water. As described above, there is a need for a sizing agent-coated textile product that is suitable for desizing using supercritical carbon dioxide.

[0005] An object of the present invention is to provide a sizing agent-coated textile product suitable for desizing using supercritical carbon dioxide. [Means for solving the problem]

[0006] As a result of intensive research to solve the above-mentioned problems, the inventors discovered that the above-mentioned problems can be solved by using a sizing agent containing an alkenyl succinic acid ester of a starch hydrolysate, and thus completed the present invention. Specific embodiments of the present invention are as follows.

[0007] [1] A sizing textile product, The sizing agent may comprise an alkenyl succinate ester of a starch hydrolysate. [2] The sizing textile product according to [1], wherein the alkenyl succinate ester of the starch hydrolysate comprises octenyl succinate ester of dextrin, octenyl succinate ester of maltose, dodecenyl succinate ester of maltose, or a combination thereof. [3] The sizing fiber product according to [1] or [2], wherein the alkenyl succinic acid content in the alkenyl succinic acid ester of the starch hydrolysate is 5 to 50% by weight. [4] The sizing textile product according to any one of [1] to [3], wherein the DE of the starch hydrolysate, which is a constituent of the alkenyl succinate ester of the starch hydrolysate, is 5 to 80. [5] The sizing textile product according to any one of [1] to [4], wherein the textile product comprises cotton yarn or cotton fabric. [6] The sizing textile product according to any one of [1] to [5], wherein the adhesion rate of the sizing agent to the sizing textile product is 0.1 to 10% by weight. [7] A sizing agent containing an alkenyl succinate ester of a starch hydrolysate for producing the sizing fiber product according to any one of [1] to [6]. [8] A method for producing a sizing-applied textile product according to any one of [1] to [6], The method further comprises a step of contacting a textile product with a fluid containing the sizing agent to size the textile product. [9] A method for producing a textile product from the sizing-applied textile product according to any one of [1] to [6], The method further comprises a step of contacting the sized textile product with a fluid containing supercritical carbon dioxide to desize the sized textile product.

[10] The method according to [9], wherein the desizing step is performed by batch processing or continuous processing. [Effects of the Invention]

[0008] The sized textile product of the present invention is suitable for desizing using supercritical carbon dioxide. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a temperature-pressure phase diagram of carbon dioxide. [Figure 2] Figure 2 is an SEM image of cotton yarn with no sizing agent attached. [Figure 3] Figure 3 shows an SEM image of cotton yarn to which alkenyl succinate ester (1), a starch hydrolyzate, is attached. [Figure 4] Figure 4 shows an SEM image of cotton yarn to which alkenyl succinate ester (2), a starch hydrolyzate, is attached. [Figure 5] FIG. 5 is a photograph of the woven fabric before treatment with a fluid containing supercritical carbon dioxide. [Figure 6] FIG. 6 is a diagram showing an outline of an apparatus used for treatment with a fluid containing supercritical carbon dioxide. [Figure 7] FIG. 7 is a diagram showing the jig with cotton thread wound around it. DETAILED DESCRIPTION OF THE INVENTION

[0010] In this specification, when a numerical range is expressed using "X to Y", the range is intended to include both end values.

[0011] The sizing textile product, the sizing agent, the method for producing the sizing textile product, and the method for producing the textile product of the present invention will be described below.

[0012] 1. Textile products with sizing agents The sizing agent-coated textile product of the present invention is In the sizing textile product, the sizing agent contains an alkenyl succinate ester of a starch hydrolyzate. The sized textile product of the present invention is suitable for desizing using supercritical carbon dioxide. In some cases, the sizing agent-coated textile product of the present embodiment is suitable for desizing using supercritical carbon dioxide, and in addition, has high resistance to friction and / or can exhibit high tensile strength and / or can exhibit high tensile elongation.

[0013] In addition, cellulose acetate has been used as a component of sizing agents in some cases. In the sizing agent-coated textile product of the present embodiment, the use of an alkenyl succinate ester of a starch hydrolysate as a component of the sizing agent has the following advantages: it is possible to use water, which is less expensive as a co-solvent, compared to the case where cellulose acetate is used, and / or it is possible to impart sufficient durability and tensile strength to the textile product even when the amount of water added or applied is small.

[0014] (sizing agent) The paste may further contain components other than the alkenyl succinate esters of the starch hydrolysates, or may contain no components other than the alkenyl succinate esters of the starch hydrolysates (the paste may consist of the alkenyl succinate esters of the starch hydrolysates). In this specification, "not containing" a particular component means that the component is not intentionally added, and does not exclude forms in which the component is contained as an impurity. The components of the starch hydrolysate other than the alkenyl succinate ester are not particularly limited, but may include or consist of corn starch, wax, propylene glycol, polyvinyl alcohol (PVA), or a combination of two or more of these.

[0015] The adhesion rate (amount of adhesion) of sizing agent to a sizing-coated textile product is not particularly limited, but is preferably 0.1 to 10% by weight, more preferably 1 to 8% by weight, most preferably 3 to 8% by weight, and can be 5 to 7.5% by weight. When the adhesion rate of sizing agent is within the above range, pilling due to friction between threads or between threads and metal is less likely to occur, and thread breakage is reduced, thereby improving weaving efficiency. The adhesion amount of sizing agent to a sizing-coated textile product can be calculated based on the method and procedure described in (5-1) of 1. [Examples] below.

[0016] The size agent is not particularly limited, but may be a size agent for warp threads of a woven fabric.

[0017] (Alkenyl succinate ester of starch hydrolysate) Alkenyl succinate esters of starch hydrolysates are esters of starch hydrolysates and alkenyl succinic acids obtained by esterifying the starch hydrolysates with alkenyl succinic acids. The esterification reaction is a reaction between some or all of the hydroxyl groups (-OH) of the starch hydrolysates and the carboxylic acid groups or carboxylic anhydride groups of the alkenyl succinic acids. Introduction of the alkenyl succinic acid structure into the starch hydrolysate molecules is thought to increase the hydrophobicity of the molecules.

[0018] The alkenylsuccinic acid content (wt%) in the alkenylsuccinic acid ester of a starch hydrolysate (particularly, the octenylsuccinic acid content (wt%)) is not particularly limited, but is preferably 5 to 50 wt%, more preferably 10 to 40 wt%, and most preferably 20 to 30 wt%. Having the alkenylsuccinic acid content (wt%) within the above range improves the hydrophobicity of the alkenylsuccinic acid ester of a starch hydrolysate. The alkenylsuccinic acid content (wt%) can be calculated based on the procedures and formulas described in "D. Component Specifications and Storage Standards," "Starch Sodium Octenylsuccinate," and "Purity Test (2)" (pages 471 and 472) of the 9th Edition of the Official Specification of Food Additives (published by the Ministry of Health, Labour and Welfare), as described in the "Examples" section below.

[0019] The degree of substitution (DS) of the alkenyl succinate group in the alkenyl succinate ester of the starch hydrolysate (the average number of alkenyl succinate groups present per glucose ring unit in the alkenyl succinate ester of the starch hydrolysate) is not particularly limited, but is preferably 0.05 to 0.7, more preferably 0.1 to 0.5, and most preferably 0.15 to 0.3. When the degree of substitution of the alkenyl succinate group is within the above range, the hydrophobicity of the alkenyl succinate ester of the starch hydrolysate is improved, and the solubility in supercritical carbon dioxide is also improved.

[0020] The molecular weight of the alkenyl succinate ester of a starch hydrolysate is not particularly limited, and is preferably 200 to 3,000, more preferably 300 to 2,000, and most preferably 400 to 1,500. When the molecular weight is within the above numerical range, the solubility of the alkenyl succinate ester of a starch hydrolysate in supercritical carbon dioxide is improved. The molecular weight of the alkenyl succinate ester of a starch hydrolysate can be calculated as a theoretical value based on the molecular weights of the starch hydrolysate and alkenyl succinic acid, which are the raw materials, and the degree of substitution (DS) of the alkenyl succinate group.

[0021] The starch hydrolysate, which is a component of the alkenyl succinate ester of the starch hydrolysate, is obtained by hydrolyzing starch with an acid, an enzyme, or the like. The starch hydrolysate in this embodiment is not particularly limited, but may contain or consist of maltose, dextrin, maltooligosaccharide, maltotriose, glucose, or the like, or a combination of two or more of these. Among these, maltose, dextrin, or a combination thereof is preferred. The use of maltose, dextrin, or a combination thereof improves the solubility of the alkenyl succinate ester of the starch hydrolysate in supercritical carbon dioxide.

[0022] DE (Dextrose equivalent) is an index used to indicate the degree of decomposition of starch hydrolysates. The DE of the starch hydrolysates of this embodiment is not particularly limited, and is preferably 5 to 80, more preferably 10 to 70, and most preferably 15 to 60. When the DE of the starch hydrolysates is within the above numerical range, the molecular weight of the alkenyl succinate esters of the starch hydrolysates is reduced, thereby improving the solubility of the esters in supercritical carbon dioxide. The DE of the starch hydrolysates can be measured by the Lane method or the WS method.

[0023] The alkenyl succinic acid, which is a constituent of the alkenyl succinate ester of the starch hydrolysate, may or may not be in the form of an acid anhydride. The number of carbon atoms in the alkenyl group in the alkenyl succinic acid is not particularly limited, but is preferably 1 to 30, more preferably 3 to 20, and most preferably 5 to 15. The alkenyl succinic acid is not particularly limited, but may comprise or consist of octenyl succinic anhydride, decenyl succinic anhydride, dodecenyl succinic anhydride, tetradecenyl succinic anhydride, hexadecenyl succinic anhydride, octadecenyl succinic anhydride, or a combination of two or more thereof. Among these, octenyl succinic anhydride, dodecenyl succinic anhydride, or a combination thereof is preferred. The use of octenyl succinic anhydride, dodecenyl succinic anhydride, or a combination thereof improves the hydrophobicity of the alkenyl succinic acid ester of the starch hydrolysate and also improves its solubility in supercritical carbon dioxide.

[0024] In the alkenyl succinate ester of a starch hydrolysate, the starch hydrolysate and alkenyl succinic acid that are its constituents can be any combination of the above-mentioned starch hydrolysates and alkenyl succinic acids. The alkenyl succinate ester of a starch hydrolysate may comprise or consist of octenyl succinate ester of dextrin, octenyl succinate ester of maltose, dodecenyl succinate ester of maltose, or a combination of two or more of these.

[0025] The method for producing alkenyl succinate esters of starch hydrolysates is exemplified below. Alkenyl succinate esters of starch hydrolysates can be produced by dissolving starch hydrolysates in water alone or in a mixed solvent of water and an organic solvent such as alcohol or acetone, adding alkenyl succinic anhydride, and reacting with stirring in the presence of a catalyst at a pH of 6 to 8. Examples of the catalyst include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide; alkali metal carbonates such as sodium carbonate, potassium carbonate, and lithium carbonate; alkali metal alkoxides such as sodium methoxide, sodium ethoxide, and potassium methoxide; ammonia; mono-, di-, or trialkylamines having an alkyl group such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, propylamine, dipropylamine, butylamine, isobutylamine, sec-butylamine, tert-butylamine, amylamine, sec-amylamine, tert-amylamine, and hexylamine; and di- or tri-alcoholamines having an alcohol group such as triethanolamine, triisopropanolamine, and diethanolamine, used alone or in combination. The alkenyl succinate ester of starch hydrolysate can be produced, for example, according to the method described in Japanese Patent Application Laid-Open No. 4-273806.

[0026] When alkenyl succinic anhydride is used, the alkenyl succinic acid ester of the starch hydrolysate undergoes a ring-opening reaction with the alkenyl succinic anhydride in the presence of the catalyst, and becomes an ester bonded to the starch hydrolysate as a single ester. The other carboxylic acid in the alkenyl succinic anhydride becomes an alkali metal salt or an amine salt in the presence of the catalyst.

[0027] When preparing a conventional starch-containing paste, it is necessary to heat the starch to a high temperature in order to dissolve and gelatinize it in a solvent. On the other hand, when preparing a paste containing an alkenyl succinate ester of a starch hydrolysate according to the present embodiment, the alkenyl succinate ester of a starch hydrolysate dissolves in a solvent even at room temperature, which has the advantage that a heating step is not required.

[0028] The content of the alkenyl succinate ester of starch hydrolysate in the paste can be 100% by weight (the paste is composed of the alkenyl succinate ester of starch hydrolysate). The content of the alkenyl succinate ester of starch hydrolysate in the paste can be 80% by weight or more, 90% by weight or more, or 95% by weight or more. Furthermore, the content of the alkenyl succinate ester of starch hydrolysate in the paste can be 100% by weight or less. The above numerical ranges can be combined in any way.

[0029] (Textiles) Examples of textile products include, but are not limited to, fibers, yarns, fabrics, etc. Examples of fibers include tow before being made into yarn. Examples of yarns include, but are not limited to, spun yarns, filament yarns, and mixed twisted yarns and blended yarns obtained by mixing and twisting these. Examples of fabrics include woven fabrics and knitted fabrics using yarns, as well as nonwoven fabrics and felts. In this embodiment, it is preferable to use yarns as textile products, and in this case, the yarns to which a sizing agent has been applied obtained by this method can be subjected to a subsequent weaving process. The textile may also comprise or consist of cotton yarn or cotton fabric.

[0030] The type of yarn is not particularly limited, but examples include natural fibers such as plant fibers like cotton and hemp, animal fibers like silk and wool, synthetic fibers like polyester and acrylic, semi-synthetic fibers like acetate, triacetate, and promix, regenerated fibers like rayon, polynosic, cupra, and lyocell, and chemical fibers like inorganic fibers like glass fiber, metal fiber, and carbon fiber. Two or more of these yarns may be blended or twisted together. These yarns may also be single yarns, two-ply yarns, three-ply yarns, or four or more twisted yarns. In this embodiment, it is preferable to use cotton yarn from the viewpoint of the feel of the towel. The type of fabric is not particularly limited, but can be the same as the type of thread described above.

[0031] The sized textile product is not particularly limited, but may be a sized yarn or a sized fabric. The sized yarn is not particularly limited, but can be used as a warp yarn of a woven fabric. The sizing fabric is not particularly limited, but can be a woven fabric including warp yarns sizing (adhering a sizing agent) containing the alkenyl succinate ester of a starch hydrolysate and weft yarns not sizing (adhering a sizing agent). Here, the weft yarns not sizing (adhering a sizing agent) containing the alkenyl succinate ester of a starch hydrolysate refer to weft yarns to which the sizing agent has not been actively applied. Therefore, the weft yarns not sizing (adhering a sizing agent) containing the alkenyl succinate ester of a starch hydrolysate may include a situation in which the warp yarns sizing (adhering a sizing agent) containing the alkenyl succinate ester of a starch hydrolysate come into contact with the weft yarns, and the sizing agent from the warp yarns is transferred to the weft yarns. Both the warp yarns sizing (adhering a sizing agent) containing the alkenyl succinate ester of a starch hydrolysate and the weft yarns not sizing (adhering a sizing agent) containing the alkenyl succinate ester of a starch hydrolysate can be cotton yarns.

[0032] 2. Adhesive The sizing agent of the present invention is a sizing agent containing an alkenyl succinate ester of a starch hydrolysate for producing the sizing textile product described in 1 above. In the sizing agent of this embodiment, the types and contents of the sizing agent, alkenyl succinate ester of starch hydrolysate, and textiles can be similar to those described in 1 above.

[0033] As mentioned in 1 above, the size may be a size for warp threads of a woven fabric.

[0034] 3. Method for producing sizing textile products The method for producing a sizing-coated textile product of the present invention comprises the steps of: A method for producing a sizing-applied textile product according to the above item 1, The method includes a step of contacting a textile product with a fluid containing the sizing agent to size the textile product.

[0035] In the method of this embodiment, the types and contents of the adhesive, alkenyl succinate ester of starch hydrolysate, textiles, etc. can be the same as those described in 1 above.

[0036] In this embodiment, the treatment conditions when the fluid containing the sizing agent is brought into contact with the textile product are not particularly limited, but from the viewpoint of improving sizing properties, the temperature can be in the range of 0 to 100°C, preferably in the range of 0 to 75°C, and most preferably in the range of 0 to 55°C. Also, from the viewpoint of improving sizing properties, the pressure is preferably 0.01 to 0.2 MPa. Furthermore, from the viewpoint of improving sizing properties, the treatment time is preferably about 60 minutes per 450 kg of textile product. The step of contacting the sizing fluid with the textile may be a batch process.

[0037] The amount of sizing agent used is not particularly limited, but for example, when cotton yarn is used as the textile product, it is preferable to use 0.03 to 0.07 g of sizing agent per 1 g of cotton yarn in order to improve sizing properties.

[0038] The content of the alkenyl succinate ester of starch hydrolysate in the sizing fluid is not particularly limited, but is preferably 0.1 to 10 wt %, more preferably 0.5 to 7 wt %, and most preferably 1 to 5 wt %. When the content of the alkenyl succinate ester of starch hydrolysate in the fluid is within the above range, the sizing concentration and adhesion amount are both minimized, while the sizing permeability into the yarn is good, leading to improved weaving efficiency.

[0039] In this embodiment, the fluid containing the adhesive agent may further contain, but is not limited to, a solvent. The solvent is not particularly limited, but may include or consist of water, glycol ether solvents, aqueous solvents such as lower alcohols, glycerin, polyethylene glycol, polypropylene glycol, DMSO, DMF, benzyl alcohol, N-methyl-2-pyrrolidone, or a combination of two or more of these. Among these, it is preferable to include water. When the fluid includes water, excellent solubility and appropriate viscosity can be obtained. The glycol ether solvent is not particularly limited, but may include or consist of ethylene glycol monobutyl ether (2-butoxyethanol) (EGME), diethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, 2-methylpentane-2,4-diol, diethylene glycol monohexyl ether, diethylene glycol dibutyl ether, triethylene glycol monobutyl ether, or a combination of two or more thereof. Of these, EGME is preferred. The lower alcohol may include, but is not limited to, methanol, ethanol, or a combination thereof. The content of the solvent in the fluid containing the adhesive is not particularly limited, but is preferably 50 to 99 wt %, more preferably 65 to 95 wt %, and most preferably 80 to 95 wt %. When the content of the solvent in the fluid containing the adhesive is within the above range, the solubility of the solid content is improved.

[0040] In this embodiment, when a solvent is used, the solvent can be sent into the processing vessel.

[0041] When a solvent is used, the ratio (mol) of the solvent to 1 to 5 g of the adhesive is not particularly limited, but from the viewpoint of improving sizing properties, 1 to 6 mol is preferred.

[0042] The method of this embodiment can be used as a sizing process, which is one of the fiber processing processes, and can also be used in combination with other fiber processing processes such as spinning, weaving, desizing, scouring, bleaching, dyeing, and finishing. Furthermore, the method for producing a sized fiber product of this embodiment can be combined with a method for producing a fiber product from a sized fiber product, which will be described later, to form a single method or production method.

[0043] In the method of this embodiment, the step of sizing the textile product may include or consist of a step of contacting a fluid containing the sizing agent with a yarn to size the yarn. In this case, the method of this embodiment may further include a step of forming a fabric using the sized yarn to form a sized fabric. In this case, the method of this embodiment may further include or consist of a step of forming a woven fabric using the sized yarn as a warp yarn to form a sized woven fabric.

[0044] 4. Method for producing textile products from sizing textile products The method for producing a textile product from a sizing-coated textile product of the present invention includes the steps of: A method for producing a textile product from the sizing-applied textile product described in 1. above, The method includes a step of contacting the sizing agent-coated textile product with a fluid containing supercritical carbon dioxide to desize the sizing agent-coated textile product. Since a sizing agent containing an alkenyl succinate ester of a starch hydrolysate is used, the method of producing textile products from sizing-coated textile products of this embodiment can efficiently remove the sizing agent.

[0045] In the method of this embodiment, the types and contents of the adhesive, alkenyl succinate ester of starch hydrolysate, textiles, etc. can be the same as those described in 1 above. In this embodiment, from the viewpoint of the feel of the towel, it is preferable to use cotton yarn as the fiber.

[0046] In this embodiment, the sizing agent-coated textile product is not particularly limited, but products obtained by the method for producing a sizing agent-coated textile product described in 3 above can be used.

[0047] In this embodiment, the treatment conditions when the fluid containing supercritical carbon dioxide is brought into contact with the sizing agent-coated textile product are not particularly limited. From the viewpoint of improving the desizing property, the temperature can be 31 to 150°C or 40 to 120°C, the pressure can be 8 to 25 MPa or 10 to 25 MPa, and the time can be 30 to 800 minutes or 120 to 180 minutes. In this embodiment, the desizing step can be a batch process or a continuous process.

[0048] In this embodiment, the fluid containing supercritical carbon dioxide may further contain a co-solvent, which can improve the solubility of the sizing agent in the solvent (containing supercritical carbon dioxide and the co-solvent) and thereby improve the removability of the sizing agent. The co-solvent is not particularly limited, and the solvents described in 3 above can be used, but it is preferable to use an aqueous solvent, a glycol ether solvent, or a combination thereof, particularly water, EGME, or a combination thereof. By using a solvent described in 3 above as the co-solvent, the solubility of the sizing agent in the solvent (including supercritical carbon dioxide and the co-solvent) can be improved, thereby improving resizing properties. This effect is particularly pronounced when water, EGME, or a combination thereof is used as the co-solvent.

[0049] In this embodiment, when a co-solvent is used, the co-solvent can be fed into the processing vessel separately from the supercritical carbon dioxide.

[0050] In this embodiment, when the desizing process is performed by batch processing and a co-solvent is used, the ratio (mol %) of the co-solvent to the supercritical carbon dioxide is not particularly limited, but from the viewpoint of improving the solubility of the adhesive in the solvent and improving the desizing properties, a ratio of 0.1 to 2 mol % is preferred. The volume ratio of supercritical carbon dioxide to co-solvent is not particularly limited, but is preferably 400:1 to 10:1, more preferably 300:1 to 25:1, and most preferably 200:1 to 40:1. The volume ratio of supercritical carbon dioxide to co-solvent can also be 150:1 to 50:1, 100:1 to 60:1, or 90:1 to 70:1.

[0051] In this embodiment, when the desizing step is a continuous process, the flow rate of supercritical carbon dioxide into the processing vessel is not particularly limited, but from the viewpoint of improving the solubility of the sizing agent in the solvent and thereby improving the desizing properties, it is preferably 50 ml to 2000 ml, and more preferably 100 ml to 1500 ml per 1 g of fiber.

[0052] In this embodiment, when the desizing step is a continuous process and a co-solvent is used, the flow rate of the co-solvent into the processing vessel is not particularly limited, but is preferably 1 ml to 500 ml, and more preferably 10 ml to 400 ml per 1 g of fiber.

[0053] The percentage of adhesive removal after desizing by the method of this embodiment is not particularly limited, but can be 1 to 99%, etc. The percentage of adhesive removal can be calculated based on the procedure and method described in Section 2 (4-1) of [Examples] below. In the method of the present embodiment, the solubility of the adhesive in the fluid containing supercritical carbon dioxide is not particularly limited, but is preferably 0.0001 to 0.01 g / ml, more preferably 0.001 to 0.008 g / ml, and most preferably 0.002 to 0.006 g / ml. The solubility of the adhesive in the fluid containing supercritical carbon dioxide is not particularly limited, but is preferably 1×10 -5 g / ml or more, 1×10 -4 g / ml or more, or 1×10 -3 The solubility of the adhesive in the fluid containing supercritical carbon dioxide is not particularly limited, but may be 1 g / ml or less, 1×10 -1 g / ml or less, or 1×10 -2The solubility of the adhesive in a fluid containing supercritical carbon dioxide can be calculated based on the procedure and method described in (4-2) of Section 2 of the Examples below.

[0054] The method of this embodiment can be used as a desizing process, which is one of the textile processing steps, and can also be used in combination with other textile processing steps such as spinning, weaving, sizing, scouring / bleaching, dyeing, and finishing. Furthermore, the method of producing a textile product from a sized textile product of this embodiment can be combined with the above-mentioned method of producing a sized textile product to form a single method or production method.

[0055] The present invention will be specifically described below with reference to examples, but the present invention is not limited to the contents described in the examples. [Example]

[0056] 1. Measurement of physical properties or observation of surface condition of sizing agents or sizing agents on textile products (1) Preparation of alkenyl succinate esters of starch hydrolysates [Alkenyl succinate esters of starch hydrolysates (1)] A reactor was charged with 500 g of water and 250 g of dextrin TK-16 (DE:18, powder, manufactured by Matsutani Chemical Industry Co., Ltd.) (the dextrin is composed of approximately five glucose molecules, and therefore, based on the glucose molecular weight of approximately 180 g / mol, the molecular weight of the dextrin can be estimated to be approximately 900 g / mol). The dextrin was dissolved in water at 30°C to obtain an aqueous solution. While maintaining the pH at 7.5 to 8.5 by adding a 3% sodium hydroxide solution to the resulting aqueous solution, 250 g of octenyl succinic anhydride (RIKACID OSA, liquid, manufactured by New Japan Chemical Co., Ltd.) was added dropwise to the aqueous solution at 30°C over 1 hour. After the dropwise addition of octenyl succinic anhydride, the mixture was allowed to react for an additional 3 hours at 30°C to obtain a solution of the reaction product. The resulting solution was subjected to vacuum freeze-drying to thoroughly remove water, ultimately yielding 550 g of powder of octenyl succinate ester of dextrin (hereinafter referred to as "alkenyl succinate ester of starch hydrolysate (1)").

[0057] The octenylsuccinic acid content (wt%) in the obtained sample of alkenylsuccinate ester (1) (powder) of starch hydrolysate was calculated to be 25 wt% based on the procedures and formulas described in "D. Component Specifications and Storage Standards," "Starch Sodium Octenylsuccinate," and "Purity Test (2)" (pages 471 and 472) of the 9th Edition of the Official Specification of Food Additives (published by the Ministry of Health, Labour and Welfare). Based on the obtained octenylsuccinic acid content (wt%), the degree of substitution (DS) of the alkenyl succinate ester (1) of the starch hydrolysate was calculated to be 0.23. Furthermore, based on the obtained DS value of 0.23, it is believed that 0.23 x 5 = 1.15 molecules of octenyl succinic anhydride (molecular weight: approximately 210) are bound to one molecule of the dextrin used (approximately five glucose molecules), so the molecular weight (theoretical value) of the alkenyl succinate ester (1) of the starch hydrolysate can be calculated to be approximately 1100.

[0058] [Alkenyl succinate esters of starch hydrolysates (2)] Finally, 550 g of a powder of octenyl succinate ester of maltose (hereinafter referred to as "alkenyl succinate ester of starch hydrolysate (2)") was obtained in the same manner as in the preparation of the above-mentioned [alkenyl succinate ester of starch hydrolysate (1)], except that 250 g of maltose (reagent, purity: 99.9%, Fujifilm Wako Pure Chemical Industries, Ltd., DE: approximately 50) (the maltose is formed from approximately two glucose molecules, and therefore the molecular weight of the maltose can be estimated to be approximately 360 g / mol based on the molecular weight of glucose: approximately 180 g / mol) was used instead of 250 g of dextrin TK-16. The octenylsuccinic acid content (wt%) in the obtained sample of alkenyl succinate ester (2) (powder) of starch hydrolysate was calculated in the same manner as in [Alkenyl succinate ester (1) of starch hydrolysate] above, and was found to be 25 wt%. Based on the obtained octenylsuccinic acid content (wt%), the degree of substitution (DS) of the alkenylsuccinic acid ester (2) of the starch hydrolysate was calculated to be 0.23. Furthermore, based on the obtained DS value of 0.23, it is believed that one molecule of the maltose used (approximately two glucose molecules) is bound to 0.23 x 2 = 0.46 molecules of octenylsuccinic anhydride (molecular weight: approximately 210), so the molecular weight (theoretical value) of the alkenylsuccinic acid ester (2) of the starch hydrolysate can be calculated to be approximately 450.

[0059] [Alkenyl succinate esters of starch hydrolysates (3)] 500 g of water and 250 g of maltose (reagent, purity: 99.9%, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., DE: approximately 50) were placed in a reactor, and the maltose was dissolved in water at 50°C to obtain an aqueous solution. While maintaining the pH at 7.5 to 8.5 by adding a 3% sodium hydroxide solution to the obtained aqueous solution, 250 g of dodecenyl succinic anhydride (RIKACID DDSA, manufactured by New Japan Chemical Co., Ltd., liquid) was added dropwise to the aqueous solution at 50°C over 1 hour. After the dropwise addition of dodecenyl succinic anhydride, the mixture was allowed to react for an additional 7 hours at 50°C to obtain a solution of the reaction product. The obtained solution was subjected to vacuum freeze-drying to thoroughly remove water, and finally, 550 g of powder of dodecenyl succinate ester of maltose (hereinafter referred to as "alkenyl succinate ester of starch hydrolysate (3)") was obtained.

[0060] (2) Preparation of an aqueous solution containing a sizing agent [Example 1] Room temperature water was added to the alkenyl succinate ester (1) of starch hydrolysate to a dilution ratio of 20 times based on the weight of the alkenyl succinate ester of starch hydrolysate, and the resulting diluted solution was stirred for a certain period of time to prepare an aqueous solution of the alkenyl succinate ester (1) of starch hydrolysate with a solids concentration of 5.0 wt %.

[0061] [Examples 2 and 3] An aqueous solution containing the alkenyl succinate ester (2) of a starch hydrolysate having a solids concentration of 5.0 wt % (Example 2) and an aqueous solution containing the alkenyl succinate ester (3) of a starch hydrolysate having a solids concentration of 5.0 wt % (Example 3) were prepared in the same manner as in Example 1, except that the alkenyl succinate ester (2) of a starch hydrolysate or the alkenyl succinate ester (3) of a starch hydrolysate was used instead of the alkenyl succinate ester (1) of a starch hydrolysate.

[0062] [Comparative Example 1]

[0063] First, water was placed in a mixer. Wheat starch (Glyco Shiranami, manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.) and a silicone glidant (Silicon Star HS12, manufactured by Nissin Chemical Laboratory Co., Ltd.) were gradually added to the water in the mixer while stirring thoroughly to prevent the formation of aggregates, and the entire amount of each component was added. After confirming that the wheat starch had dissolved, wax (Maconol 88, manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.) was gradually added while stirring thoroughly, and the entire amount of wax was added to obtain a mixed solution. The resulting mixed solution was heated at 92°C for 30 minutes and then at 83°C for 10 minutes to dissolve and gelatinize the wheat starch components, preparing an aqueous starch paste solution (wheat starch content: 3.5 g / L, wax content: 2.5 g / L, silicone glidant content: 0.5 g / L).

[0064] (3) Equipment and reagents The sizing machines used were a Minisizer DCI001P (manufactured by Kaji Seisakusho Co., Ltd.) and an HGA-357 type sizing machine (manufactured in China, with a glue tank capacity of approximately 47 L).

[0065] (4) Operation procedure [Example 1] 2500 ml of the aqueous solution of the alkenyl succinate (1) of the starch hydrolysate of Example 1 obtained in (2) above was placed in the above-mentioned sizing machine: Minisizer DCI001P. In addition, cotton yarn (1) (raw silk (unbleached yarn, spun yarn, etc.), 100% cotton, 20 count, single yarn, twist coefficient 4.5, average fiber length approximately 25 mm) manufactured by Izawa Towel Co., Ltd., fed from a cheese bobbin, was introduced into an aqueous solution of the starch hydrolysate alkenyl succinate (1) in a sizing machine. The cotton yarn with the sizing solution (aqueous solution) attached was then passed through a squeezing roll (first pass roll) under a pressure load of 0.04 MPa and an immersion roll (second pass roll) under a pressure load of 0.06 MPa, and further passed through a hot air drying section with a temperature of 110°C and a drying chamber length of approximately 3.8 m, and a drying section with a temperature of 110°C and eight cylinder rolls with a diameter of 150 mm each at a speed of 15 m / min, thereby carrying out a sizing process. The weight of the cotton yarn (1) per unit length was measured for each of the cotton yarn (1) fed from the cheese bobbin (before sizing) and the cotton yarn (1) obtained as described above after drying (after sizing).

[0066] [Examples 2 and 3] Except for using 2500 mL of the aqueous solution of the alkenyl succinate ester (2) of the starch hydrolysate (Example 2) or 2500 mL of the aqueous solution of the alkenyl succinate ester (3) of the starch hydrolysate (Example 3) instead of 2500 mL of the aqueous solution of the alkenyl succinate ester (1) of the starch hydrolysate, sizing treatment was carried out in the same manner as the cotton yarn sizing treatment of Example 1. Then, for each of Examples 2 and 3, the weight per unit length of the cotton yarn (1) fed from the cheese bobbin and the weight per unit length of the resulting cotton yarn (1) after drying (after sizing) were measured in the same manner as in Example 1.

[0067] [Comparative Example 1] 35 L of the aqueous solution of starch paste of Comparative Example 1 obtained in (2) above was placed into the above-mentioned sizing machine: HGA-357 type sizing machine. In addition, cotton yarn (1) manufactured by Izawa Towel Co., Ltd. (raw silk (unbleached yarn, spun yarn, etc.), 100% cotton, 20 count, single yarn, twist coefficient 4.5, average fiber length approximately 25 mm) fed from a cheese bobbin was introduced into the aqueous solution of starch glue in a sizing machine. At this time, the weight of the cotton yarn (1) per unit length fed from the cheese bobbin was measured. The cotton yarn with the glue solution (aqueous solution) attached was then passed through a drying chamber of approximately 20 m and dried at 300°C. Next, excess glue was removed using a cylinder roll at approximately 120°C, and the resulting sized cotton yarn (1) was wound around a weaving beam. The speed at which the cotton yarn passed through the drying chamber and cylinder roll was 30 m / min. The weight of the resulting dried (sized) cotton yarn (1) per unit length was measured.

[0068] (5) Evaluation The following evaluations (5-1) to (5-3) were carried out for each of the sized yarns of Examples 1 to 3 and Comparative Example 1. The following evaluation (5-4) was also carried out for each of the sized yarns of Examples 1 and 2. Furthermore, the above cotton yarn (1) before sizing was also evaluated for each of the following evaluations (5-2) to (5-4). (5-1) Adhesion rate (amount of adhesive) For each sized yarn, the weight (g) of the cotton yarn before sizing (weight before treatment) and the weight (g) of the cotton yarn after sizing (weight after treatment) were used to calculate the adhesion rate (amount of adhesion) of the sizing agent (Sizing rate S) based on the following formula (1).

[0069]

number

[0070] (5-2) Abrasion resistance (number of frictions) The abrasion resistance of each sized yarn was measured using a bonding tester (1065, manufactured by Maeda Seisakusho) in accordance with JIS L 1095:2010 (9.10 Abrasion Resistance Method B). Specifically, an abrasion test was conducted under the following test conditions, and the number of times of friction until two of the 20 samples broke was measured. <Test conditions> ·Friction speed: 120 times / min ·Friction angle: 110 degrees ·Round distance: 2.5cm Test length: 20cm Friction element: 0.6mm diameter hard steel wire

[0071] (5-3) Single yarn tensile strength and elongation For each sized yarn, a tensile tester (Autograph AG-Xplus, manufactured by Shimadzu Corporation) was used to measure the single yarn tensile strength and elongation based on JIS L 1095:2010 (9.5 Single yarn tensile strength and elongation) under the conditions of a gripping distance of 20 cm and a pulling speed of 20 cm / min.

[0072] (5-4) Observation by scanning electron microscope Using a tabletop microscope (Miniscope (registered trademark) TM4000Plus, manufactured by Hitachi High-Technologies Corporation) at an accelerating voltage of 15 kV, the surfaces of the cotton yarns used in Examples 1 to 3 before sizing and the cotton yarns used in Examples 1 and 2 after sizing were observed.

[0073] The evaluation results of (5-1) to (5-3) above are shown in Table 1. 2 to 4 show the results of the SEM observations in (5-4) above for Examples 1 and 2. The correspondence between Figures 2 to 4 is as follows. Figure 2: SEM image of cotton thread without sizing agent used in Examples 1 to 3 (magnification: 150x) Figure 3: SEM image of cotton yarn to which the starch hydrolysate alkenyl succinate (1) from Example 1 is attached (magnification: 150x) Figure 4: SEM image of cotton yarn to which alkenyl succinate ester (2), a starch hydrolysate from Example 2, is attached (magnification: 150x)

[0074] [Table 1]

[0075] The results in Table 1 show that the cotton yarns of Examples 1 to 3 (cotton yarns to which any of the starch hydrolysates, alkenyl succinic acid esters (1) to (3) has been attached) have improved performance in terms of number of frictions, single yarn tensile strength, and elongation compared to the cotton yarn (1) before sizing, and are excellent in abrasion resistance, single yarn tensile strength, and elongation. The cotton yarns of Examples 1 to 3 were found to have performance comparable to that of the starch-sizing cotton yarn of Comparative Example 1 in terms of number of frictions, single yarn tensile strength, and elongation, and were found to be at a level that would not pose any practical problems as cotton yarns with starch sizing agents.

[0076] Furthermore, the SEM photographs in Figures 3 and 4 show that when the starch hydrolysate alkenyl succinate ester (1) or the starch hydrolysate alkenyl succinate ester (2) was used as a sizing agent, fuzzing was suppressed and the entire surface was fixed with the sizing agent.

[0077] The results in Table 1 and Figures 2 to 4 above demonstrate that the alkenyl succinate esters of starch hydrolysates of the present invention have excellent convergence properties. Furthermore, it was shown that any of the aqueous solutions containing the alkenyl succinate esters of starch hydrolysates (1), (2), or (3) can be used as a sizing agent, demonstrating that the alkenyl succinate esters of starch hydrolysates are useful as sizing agents regardless of their type.

[0078] 2. Desizing using supercritical carbon dioxide (1) Preparation of fabric or cotton yarn with sizing agent [Dough coated with alkenyl succinate (1), a starch hydrolysate] Cotton yarn (1) (Example 1, size deposition rate: 5.2 wt% (Table 1)) (No. 20 single yarn) (used as pile yarn) and cotton yarn (TS cotton yarn, manufactured by KB Tsuzuki Co., Ltd., No. 30 two-ply yarn) were used as warp yarns, and cotton yarn (TS cotton yarn, manufactured by KB Tsuzuki Co., Ltd., No. 20 single yarn) was used as weft yarns. A woven fabric (warp density: 40 threads / inch, weft density: 45 threads / inch; in the fabric, size-deposited cotton yarn (1): approximately 30%, TS cotton yarn: approximately 30%, TS cotton yarn: approximately 40% in the warp, TS cotton yarn: approximately 40% in the weft) was woven on a loom (Itema loom, manufactured by Italy). The size deposition rate of the entire woven fabric was calculated to be 1.6 wt%. The appearance of the resulting woven fabric is shown in Figure 5.

[0079] [Cotton thread with starch attached] The sized cotton yarn (1) was obtained and wound onto a weaving beam in the same manner as in 1.(4) [Comparative Example 1] above, except that various operating conditions such as the drying temperature, the amount of starch removed by the cylinder roll, and the cotton yarn passing speed were adjusted so that the final sized yarn had a sizing agent (starch) adhesion rate (adhesion amount) of 3.8% by weight.

[0080] (2) Equipment and reagents An overview of the entire equipment used in the treatment with a fluid containing supercritical carbon dioxide is shown in Figure 6. The symbols in Figure 6 indicate: 1: chiller unit, 2: CO2 supply pump, 3: air vent valve, 4: check valve, 5: pressure transmitter, 6: safety valve, 7: dyeing vessel, 8: vessel drain valve, 9: vessel temperature sensor, 10: magnetic induction stirrer, 11: exhaust flow control valve, 12: vessel exhaust valve, 13: control panel, 14: outlet for CO2 supply pump, 15: outlet for dyeing vessel heater, and A: CO2 cylinder. The chiller unit 1 used was a cooling water circulation system LTC-450α (manufactured by AS ONE Corporation), the CO2 supply pump 2 used was a double plunger pump NP-KX-500 (manufactured by Nippon Seimitsu Kagaku Co., Ltd.), and the dyeing vessel 7 used was a high-pressure vessel (manufactured by ITEC Corporation, model: C-04-M-FU, capacity: 400 ml). A liquefied carbon dioxide cylinder (Kind Gas Co., Ltd., purity 99.5% or higher) was used as the carbon dioxide supply source.

[0081] (3) Operation procedure (3-1) Fabric with glue attached (3-1-1) Use of water as a co-solvent A jig (110 cm long x 15 mm outer diameter, hollow cylinder, mesh structure, made of metal) was prepared, and the woven fabric of the example (using cotton yarn (1) with starch hydrolysate alkenyl succinate ester (1) glued to the warp) (approximately 9 cm x approximately 21 cm, approximately 10 g) obtained in 2.(1) [Fabric with starch hydrolysate alkenyl succinate ester (1)] above was wrapped around the jig. A cotton string was further wrapped around the wrapped fabric to secure it in place. An outer cylinder (a hollow cylinder with a length of 110 cm, an inner diameter of 36 mm, and an outer diameter of 41 mm) was prepared, and a paper wiper (Kimwipes (registered trademark), 120 mm x 210 mm) that had been soaked evenly with 2 ml of water (a co-solvent) was wrapped around the outside of the outer cylinder. A cotton string was further wrapped around the wrapped paper wiper to secure it in place. The jig wrapped around the fabric was placed and secured inside an outer cylinder wrapped with paper wipes to obtain a measurement sample. The resulting measurement sample was placed in dyeing vessel 7. Next, 200 ml of carbon dioxide was delivered to dyeing vessel 7 using CO2 supply pump 2 at a flow rate of 20 to 300 ml / min, pressurizing the dyeing vessel 7. The conditions for treating the measurement sample with supercritical carbon dioxide fluid were 120°C, 25 MPa, 180 minutes, batchwise, and agitated using a propeller. One set consisted of 60 seconds of forward rotation and 60 seconds of reverse rotation, and this set was repeated at 900 rpm for 180 minutes. The water soaked in the paper wipes was mixed with supercritical carbon dioxide, resulting in a supercritical carbon dioxide:fabric volume ratio of 40:1 and a supercritical carbon dioxide:water volume ratio of 200:1. After treatment with supercritical carbon dioxide fluid, the valve of dyeing vessel 7 was opened to release pressure to atmospheric pressure. After the pressure in the dyeing vessel 7 was released, the fabric was taken out of the jig and dried at 105°C for 2 hours, and the dried fabric was weighed.

[0082] (3-1-2) EGME used as a co-solvent The test sample was prepared and treated with supercritical carbon dioxide fluid in the same manner as in (3-1-1) above, except that 5 ml of EGME (ethylene glycol monobutyl ether) was used instead of 2 ml of water as the co-solvent to be soaked into the paper wiper. The test sample was then removed from the jig, dried, and weighed. The EGME soaked into the paper wiper was mixed with supercritical carbon dioxide, resulting in a supercritical carbon dioxide:fabric volume ratio of 40:1 and a supercritical carbon dioxide:EGME volume ratio of 80:1.

[0083] (3-2) Cotton yarn coated with alkenyl succinate ester (1) of starch hydrolysate (3-2-1) 1 ml of water was used as a co-solvent. Instead of wrapping the woven fabric of the example obtained in 2.(1) above [Fabric coated with alkenyl succinate ester (1) of starch hydrolysate] around the jig, cotton yarn (1) (Example 1, sizing rate: 5.2 wt% (Table 1)) (length: approximately 400 m, approximately 10 g) coated with alkenyl succinate ester (1) of starch hydrolysate prepared in 1.(4) above was wrapped around the jig. The amount of water used as the cosolvent in the paper wiper was changed from 2 ml to 1 ml. The test sample was prepared and treated with supercritical carbon dioxide fluid in the same manner as in (3-1-1) above. The cotton yarn was then removed from the jig, dried, and weighed. The water soaked in the paper wiper was mixed with supercritical carbon dioxide, resulting in a volume ratio of supercritical carbon dioxide:cotton yarn of 40:1 and a volume ratio of supercritical carbon dioxide:water of 400:1.

[0084] (3-2-2) 2 ml of water was used as a co-solvent, and the treatment time was 360 minutes. The test sample was prepared and treated with supercritical carbon dioxide fluid in the same manner as in (3-2-1) above, except that the amount of water used as a cosolvent to soak the paper wiper was changed from 1 ml to 2 ml, and the treatment time with supercritical carbon dioxide fluid was changed from 180 minutes to 360 minutes. The test sample was then removed from the jig, dried, and weighed. The water soaked into the paper wiper was mixed with supercritical carbon dioxide, resulting in a supercritical carbon dioxide:cotton yarn volume ratio of 40:1 and a supercritical carbon dioxide:water volume ratio of 200:1.

[0085] (3-3) Cotton yarn coated with alkenyl succinate ester (2) of starch hydrolysate A test sample was prepared and treated with supercritical carbon dioxide fluid in the same manner as in (3-1-1) above, except that instead of wrapping the woven fabric of the example obtained in 2.(1) above [fabric coated with alkenyl succinate ester (1) of starch hydrolysate] around the jig, cotton yarn (1) (Example 2, sizing rate: 7.1 wt% (Table 1)) (length: approximately 400 m, approximately 10 g) coated with alkenyl succinate ester (2) of starch hydrolysate prepared in 1.(4) above was wrapped around the jig. The cotton yarn was then removed from the jig, dried, and weighed. The water soaked into the paper wiper was mixed with supercritical carbon dioxide, resulting in a supercritical carbon dioxide:cotton yarn volume ratio of 40:1 and a supercritical carbon dioxide:water volume ratio of 200:1.

[0086] (3-4) Cotton yarn coated with alkenyl succinate ester (3), a starch hydrolysate A test sample was prepared and treated with supercritical carbon dioxide fluid in the same manner as in (3-1-1) above, except that instead of wrapping the woven fabric of the example obtained in 2.(1) above [fabric coated with alkenyl succinate ester (1) of starch hydrolysate] around the jig, cotton yarn (1) (Example 3, sizing rate: 2.9 wt% (Table 1)) (length: approximately 400 m, approximately 10 g) coated with alkenyl succinate ester (3) of starch hydrolysate prepared in 1.(4) above was wrapped around the jig. The cotton yarn was then removed from the jig, dried, and weighed. The water soaked into the paper wiper was mixed with supercritical carbon dioxide, resulting in a supercritical carbon dioxide:cotton yarn volume ratio of 40:1 and a supercritical carbon dioxide:water volume ratio of 200:1.

[0087] (3-5) Cotton thread with starch paste A test sample was prepared and treated with supercritical carbon dioxide fluid in the same manner as in (3-1-1) above, except that instead of wrapping the woven fabric of Example 1 obtained in 2.(1) above around the jig, cotton yarn (1) (corresponding to a comparative example, starch adhesive rate: 3.8 wt%) (length: approximately 400 m, approximately 10 g) was wrapped around the jig. The test sample was then weighed after being removed from the jig and dried. The water soaked into the paper wiper was mixed with supercritical carbon dioxide, resulting in a supercritical carbon dioxide:cotton yarn volume ratio of 45:1 and a supercritical carbon dioxide:water volume ratio of 200:1.

[0088] (4) Evaluation The evaluation results for the following items (4-1) and (4-2) are shown in Table 2. The sample numbers in Table 2 correspond to the above-mentioned items (3-1-1) to (3-5), respectively. (4-1) Adhesive removal rate The size removal rate (Desizing rate D) was calculated based on the following formula (2) using the size adhesion rate (%) of the sized fabric or cotton yarn (fabric or cotton yarn after sizing treatment and before desizing treatment) (sized fabric: 1.6% by weight as described above, sized cotton yarn: 5.2, 7.1, 2.9, or 3.8% by weight as described above) and the size adhesion rate (%) of the fabric or cotton yarn after the above-mentioned desizing treatment.

[0089]

number

[0090] (4-2) Solubility of adhesives in supercritical carbon dioxide fluid The solubility (g / ml) of the paste (alkenyl succinate (1) or starch paste) in the supercritical carbon dioxide fluid (total of supercritical carbon dioxide and cosolvent) was calculated based on the following formula (3).

[0091]

number

[0092] [Table 2]

[0093] The results for Samples 3-1-1 and 3-1-2, which treated the woven fabrics in Table 2, showed that desizing with supercritical carbon dioxide was sufficient to remove alkenyl succinate esters, a starch hydrolyzate, from the fabric. Furthermore, the size removal rate did not change between the cases where the co-solvent was 2 ml of water (Sample 3-1-1) and 5 ml of EGME (Sample 3-1-2). These results suggest that using 2 ml of water as a co-solvent, which requires less additives, is a more effective method.

[0094] The results of samples 3-2-1 and 3-2-2 in Table 2, which were cotton yarn samples, show that alkenyl succinate esters, which are starch hydrolysates, can be sufficiently removed from yarn by desizing with supercritical carbon dioxide. It was also found that the removal rate of sizing agent increased by increasing the amount of co-solvent used and by extending the treatment time with supercritical carbon dioxide fluid.

[0095] Samples 3-1-1 and 3-1-2, which were treated with woven fabric, had a higher rate of sizing agent removal than samples 3-2-1 and 3-2-2, which were treated with yarn. Without being bound by theory, it is presumed that this is because the winding conditions around the jig differed between the woven fabric and the yarn, making the woven fabric more susceptible to contact with the supercritical carbon dioxide fluid.

[0096] Comparing the results of Sample Nos. 3-2-1 and 3-2-2 with the results of Sample Nos. 3-3 and 3-4, in which the type of alkenyl succinate ester of the starch hydrolysate was changed, it was found that even if the type of alkenyl succinate ester of the starch hydrolysate was changed, the alkenyl succinate ester of the starch hydrolysate could be sufficiently removed by desizing treatment using supercritical carbon dioxide. Furthermore, sample number 3-4, which used alkenyl succinate ester (3), a starch hydrolysate, showed a particularly high rate of sizing removal. Without being bound by theory, it can be inferred that the higher hydrophobicity of the alkenyl group in alkenyl succinate ester (3), a starch hydrolysate, results in higher hydrophobicity of the alkenyl succinate ester (3), making it easier to remove the size using supercritical carbon dioxide fluid. Furthermore, sample number 3-4 showed a sizing removal rate of over 100%, which is thought to be due to the removal of components other than the sizing agent that were originally contained in the cotton yarn during the desizing process.

[0097] The results of sample number 3-5 (comparison example) in Table 2, which was a cotton yarn treated with starch paste, showed that the starch paste could not be sufficiently removed by desizing treatment using supercritical carbon dioxide. A comparison of sample numbers 3-2-1, 3-2-2, 3-3, and 3-4 in Table 2 with sample number 3-5 (comparison example) shows that desizing treatment using supercritical carbon dioxide shows a much higher removal rate of alkenyl succinate esters, which are starch hydrolysates, than starch paste.

[0098] From the above, it was found that the sizing agent-coated textile product of the present invention is suitable for desizing using supercritical carbon dioxide. Furthermore, from the above results, it was found that the sizing agent-coated textile product of this embodiment is suitable for desizing using supercritical carbon dioxide, and is also highly resistant to friction, or can exhibit high tensile strength, or can exhibit high tensile elongation. [Explanation of symbols]

[0099] 1: Chiller unit 2: CO2 supply pump 3: Air release valve 4: Check valve 5: Pressure transmitter 6: Safety valve 7: Dyeing vessel 8: Container drain valve 9: Temperature sensor inside the container 10: Magnetic induction stirrer 11: Exhaust flow control valve 12: Container exhaust valve 13: Control panel 14: CO2 supply pump outlet 15: Outlet for dyeing vessel heater A: CO2 cylinder

Claims

1. A sizing fiber product, the adhesive contains an alkenyl succinate ester of a starch hydrolysate, the alkenyl succinate ester of the starch hydrolysate comprises octenyl succinate ester of dextrin, octenyl succinate ester of maltose, dodecenyl succinate ester of maltose, or a combination thereof; The sized textile product, wherein the textile product is selected from the group consisting of fibers, yarns, woven fabrics, and knitted fabrics.

2. 2. The sizing textile product according to claim 1, wherein the alkenyl succinic acid content in the alkenyl succinic acid ester of the starch hydrolyzate is 5 to 50% by weight.

3. A sizing-agent-coated textile product as described in claim 1 or 2, wherein the alkenyl succinate ester of the starch hydrolysate comprises octenyl succinate ester of maltose, dodecenyl succinate ester of maltose, or a combination thereof.

4. A sizing agent containing an alkenyl succinic acid ester of a starch hydrolysate for producing the sizing textile product according to claim 1 or 2, The sizing agent, wherein the alkenyl succinate ester of a starch hydrolysate comprises octenyl succinate ester of dextrin, octenyl succinate ester of maltose, dodecenyl succinate ester of maltose, or a combination thereof.

5. A method for producing the sizing-coated textile product according to claim 1 or 2, comprising: The method includes a step of contacting a textile product with a fluid containing the sizing agent to size the textile product, The method as described above, wherein the content of the alkenyl succinate ester of the starch hydrolysate in the fluid containing the paste is 0.1 to 10% by weight.

6. The fluid containing the adhesive further contains a solvent, the solvent comprises water, a glycol ether solvent, or a combination thereof; 6. The method according to claim 5, wherein the content of the solvent in the fluid containing the adhesive agent is 50 to 99% by weight.

7. The fluid containing the adhesive further contains a solvent, the solvent comprises a glycol ether solvent, 6. The method of claim 5, wherein the glycol ether solvent comprises ethylene glycol monobutyl ether.

8. A method for producing a textile product from a sizing agent-coated textile product, comprising: The method includes a step of contacting the sizing agent-coated textile product with a fluid containing supercritical carbon dioxide to desize the sizing agent-coated textile product, the adhesive contains an alkenyl succinate ester of a starch hydrolysate, The method, wherein the alkenyl succinate ester of the starch hydrolysate comprises octenyl succinate ester of dextrin, octenyl succinate ester of maltose, dodecenyl succinate ester of maltose, or a combination thereof.

9. 9. The method of claim 8, wherein the desizing step is by a batch process or a continuous process.

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