JP7348461B2 - Water-repellent fabric and method for producing the same - Google Patents

Description

The present invention relates to a water-repellent fabric and a method for producing the same. Specifically, the present invention relates to a water-repellent fabric containing water-repellent regenerated cellulose fibers and dyed with a reactive dye, and a method for producing the same.

Regenerated cellulose fibers such as rayon fibers have excellent texture and are biodegradable, so they are used in various textile products such as clothing. Regenerated cellulose fibers such as rayon fibers have high hydrophilicity, so when used for applications requiring water repellency, regenerated cellulose fibers are used after being imparted with water repellency. For example, in Patent Document 1, water and cellulose fibers are put in a container, isocyanate and fluororesin are added, and heated to 100 to 180°C to crosslink the fluororesin to cellulose fibers. It has been proposed to impart water repellency. Patent Document 2 proposes imparting water repellency to the cellulose fiber material by treating the cellulose fiber material with a compound that reacts with hydroxyl groups and then treating it with a fluorine-based water repellent.
Furthermore, a water-repellent dyed fabric is disclosed in which cellulose fibers are subjected to hydrophobic or water-repellent treatment in advance and then dyed. Patent Document 3 discloses a technique of transferring and dyeing hydrophobically modified cellulose fibers with a disperse dye. Patent Document 4 discloses a technique of dyeing a water-repellent cellulose fiber cloth by naphthol dyeing, vinyl sulfone cold fix method, and threne dyeing method. Patent Document 5 discloses a technique of dyeing only cellulose fibers by combining cellulose water-repellent fibers treated with a fluorine-based water repellent and cellulose fibers.

JP2002-266241A Japanese Patent Application Publication No. 2003-20570 Japanese Unexamined Patent Publication No. 57-128282 Japanese Unexamined Patent Publication No. 60-34687 JP2018-197406A

However, when fabrics using water-repellent cellulose fibers cross-linked with fluorine-based water repellents are immersed in a dye bath and dyed, the dyeability is poor, resulting in uneven dyeing and poor dye fastness. There was a problem with the decline. In addition, when using a dyeing process that removes the water repellent agent during dyeing or makes cellulose hydrophobic to the extent that it suppresses the hydrophilicity, there is a problem that the water repellency performance decreases and it is not possible to obtain the desired water repellency. Ta.

In order to solve the above-mentioned conventional problems, the present invention provides a water-repellent fabric that includes water-repellent regenerated cellulose fibers with a water-repellent bonded to the fiber surface, has no uneven dyeing, has high color fastness, and has durable water repellency. and a manufacturing method thereof.

The present invention provides a water-repellent fabric containing water-repellent regenerated cellulose fibers, the water-repellent regenerated cellulose fibers containing a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups, A crosslinking agent and a non-fluorine water repellent are bonded to the fiber surface, the water repellent fabric is dyed with a reactive dye, and the water repellent fabric has a contact angle with water of 90° or more. This invention relates to a water-repellent fabric.

The present invention also provides a method for producing a water-repellent fabric containing water-repellent regenerated cellulose fibers, the method comprising regenerated cellulose fibers containing a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups. A step of obtaining water-repellent regenerated cellulose fibers by bonding a non-fluorinated water repellent to the fiber surface using a crosslinking agent, a step of obtaining a water-repellent fabric containing the water-repellent regenerated cellulose fibers, a step of bonding a non-fluorine-based water repellent agent to the fiber surface using a cross-linking agent, a step of obtaining a water-repellent fabric containing the water-repellent regenerated cellulose fibers, and a step of obtaining a water-repellent fabric containing water and/or an interface. The present invention relates to a method for producing a water-repellent fabric, which includes the steps of applying an aqueous solution containing an activator to make it hydrophilic, dyeing the hydrophilized fabric with a reactive dye, and drying the dyed fabric.

According to the present invention, it is possible to provide a water-repellent fabric that contains water-repellent regenerated cellulose fibers with a water-repellent bonded to the fiber surface, has no uneven dyeing, has high color fastness, and has durable water repellency.
Further, according to the production method of the present invention, a water-repellent fabric containing water-repellent regenerated cellulose fibers with a water-repellent bonded to the fiber surface, which has no uneven dyeing, high color fastness, and durable water-repellency can be obtained. be able to.

The present inventor has made efforts to eliminate uneven dyeing during dyeing, increase color fastness, and impart durable water repellency to water-repellent fabrics containing water-repellent regenerated cellulose fibers with a water-repellent bonded to the fiber surface. investigated. As a result, regenerated cellulose fibers such as rayon fibers are impregnated with a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups, and a crosslinking agent and a non-fluorine water repellent are applied to the fiber surface. It has been found that by bonding, the fixation of the non-fluorine-based water repellent on the fiber surface is increased, and that by including the water-repellent regenerated cellulose fibers in the fabric, durable water repellency can be imparted to the fabric. In addition, by applying water or an aqueous solution containing a surfactant to a fabric containing water-repellent regenerated cellulose fibers bonded with a non-fluorinated water repellent before dyeing, the non-fluorinated water repellent can be removed from the surface of the fiber. It has been found that by disrupting the orientation of the water-repellent groups and making them temporarily hydrophilic, when dyeing with a reactive dye, dyeing can be done evenly and color fastness can be improved. In addition, since the fabric contains water-repellent regenerated cellulose fibers that have a high ability to fix non-fluorine-based water repellents on the fiber surface, the non-fluorine-based water repellent does not fall off during the hydrophilic treatment and dyeing process before dyeing. discovered that drying after dyeing restores highly durable water repellency.

The water-repellent regenerated cellulose fiber contains a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups. In the following, unless otherwise specified, "a compound containing an acidic group" means a compound containing one or more acidic groups selected from the group consisting of a carboxyl group and a sulfonic acid group. When producing regenerated cellulose fibers, by spinning a spinning viscose solution prepared by mixing a compound containing an acidic group with a viscose stock solution, the compound containing an acidic group is kneaded into the fiber. Regenerated cellulose fibers can be impregnated with compounds containing acidic groups by immersing them in an aqueous solution containing compounds containing acidic groups, or by spraying or applying an aqueous solution containing compounds containing acidic groups to regenerated cellulose fibers. A compound containing an acidic group can be included in the regenerated cellulose fiber by attaching the compound containing an acidic group to the regenerated cellulose fiber. Among these, kneading is preferred because the acidic group-containing compound is uniformly mixed and dispersed throughout the surface and interior of the fiber.

The carboxyl group-containing compound is not particularly limited, but is preferably a (meth)acrylic acid polymer, for example, from the viewpoint of easily imparting carboxyl groups to regenerated cellulose fibers. In the present invention, (meth)acrylic acid includes acrylic acid and methacrylic acid. The (meth)acrylic acid polymer may be a homopolymer of (meth)acrylic acid monomers or a copolymer of (meth)acrylic acid monomers and other monomers. It's okay. The carboxyl group-containing compound is more preferably one or more selected from the group consisting of polyacrylic acid and acrylic acid-maleic acid copolymer.

As the polyacrylic acid, it is preferable to use, for example, unneutralized polyacrylic acid, that is, H-type polyacrylic acid in which the carboxyl group of polyacrylic acid is in the H-type. Note that the H site of the carboxyl group of polyacrylic acid may be partially substituted with a metal ion such as Na or an ionic compound. In the following, unless otherwise specified, polyacrylic acid means an unneutralized product of polyacrylic acid. As the polyacrylic acid, a compound having a structure in which carboxyl groups are mainly attached to the main chain and in which the contribution of carboxyl groups to the molecular weight of the polymer is maximum can be used, for example, a compound with a theoretical amount of carboxyl groups of 72 g/mol It is preferable to use the above polyacrylic acid.

The acrylic acid-maleic acid copolymer contains an ethylenically unsaturated monomer containing at least one selected from the group consisting of acrylic acid and acrylates (hereinafter also referred to as acrylic acid monomer). , a polymer of ethylenically unsaturated monomers containing at least one selected from the group consisting of maleic acid, maleic acid salts and maleic anhydride (hereinafter also referred to as maleic acid monomers). Often, a polymer of ethylenically unsaturated monomers containing at least one member selected from the group consisting of acrylic acid and acrylates, and at least one member selected from the group consisting of maleic acid, maleate salts, and maleic anhydride. It may be. In addition, from the viewpoint of easily imparting carboxyl groups to fibers, the acrylic acid-maleic acid copolymer contains an ethylenically unsaturated monomer containing at least one selected from the group consisting of acrylic acid and acrylates, and maleic acid. A polymer of ethylenically unsaturated monomers containing at least one selected from the group consisting of acids and maleates, and/or at least one selected from the group consisting of acrylic acid and acrylates, and maleic acid. It is preferably a polymer of ethylenically unsaturated monomers containing at least one selected from the group consisting of maleate and maleate. In addition, if necessary, the acrylic acid-maleic acid polymer may be copolymerized with other monomers other than the acrylic acid monomer and the maleic acid monomer to the extent that the effects of the present invention are not impaired. It may be something that has been done. The other monomer may be, for example, an unsaturated monocarboxylic acid monomer.

The weight average molecular weight of the acrylic acid-maleic acid copolymer is preferably 5,000 or more and 500,000 or less, more preferably 6,000 or more and 250,000 or less, even more preferably 10,000 or more and 100,000 or less, and 30,000 or more and 80,000 or less. The following is particularly preferable. When the weight average molecular weight is within the above range, it is easy to knead into the regenerated cellulose, and the carboxyl group-containing compound is less likely to fall off or denature even when washed, dyed or washed.

The acrylic acid-maleic acid copolymer preferably contains 5% by mass or more and 95% by mass or less of maleic acid, more preferably 20% by mass or more and 80% by mass or less, and 30% by mass or more and 70% by mass or less. It is more preferable that the content is 40% by mass or more and 60% by mass or less. When the content of maleic acid in the acrylic acid-maleic acid copolymer is within the above range, carboxyl groups can be easily imparted to the regenerated cellulose fibers. When the same mass of acrylic acid-maleic acid copolymer is contained in the regenerated cellulose fiber, the amount of H-type carboxyl groups will be increased by including the acrylic acid-maleic acid copolymer with a high maleic acid ratio. Therefore, it is preferable.

In the present invention, the maleic acid ratio in the acrylic acid-maleic acid copolymer is measured and calculated as follows, assuming that the organic components in the acrylic acid-maleic acid copolymer are only acrylic acid and maleic acid. can do.
(1) Place about 4 to 5 mL of the sample (aqueous solution containing acrylic acid-maleic acid copolymer salt) into a glass vial, and heat and dry at 110° C. for 20 hours.
(2) Dissolve about 50 mg of the dry sample in about 0.7 mL of heavy water.
(3) Perform 1H-NMR analysis on the heavy water solution of the sample using an FT-NMR device (manufactured by JEOL Ltd., JMTC-300/54/SS). The composition ratio of the acrylic acid component (A) and the maleic acid component (M) is determined from the abundance ratio of the group carbon. The number of measurements is 16, and the average value is calculated.

The compound containing the sulfonic acid group is not particularly limited, but for example, naphthalene sulfonate, polystyrene sulfonate, phenol sulfonate, dihydroxydiphenyl sulfone, formalin condensate of hydroxyphenyl sulfone, etc. can be used.

In the water-repellent regenerated cellulose fiber, the content of the compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups is, for example, 1% by mass or more and 35% by mass based on 100% by mass of cellulose. % or less, more preferably 3% by mass or more and 30% by mass or less, and even more preferably 4% by mass or more and 25% by mass or less. In the water-repellent regenerated cellulose fiber, if the content of the compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups is less than 1% by mass based on 100% by mass of cellulose, the acidic groups may It tends to be difficult to exert its effect, and if it exceeds 35% by mass, the fiber strength decreases and there is a possibility that it may not be possible to form fine fibers.

In the water-repellent regenerated cellulose fiber, the total amount of one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups is preferably 0.30 mmol/g or more and 1.60 mmol/g or less, more preferably 0. It is .35 mmol/g or more and 1.50 mmol/g or less, more preferably 0.40 mmol/g or more and 1.40 mmol/g or less. When the total amount of one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups is within the above-mentioned range, the effect of the acidic groups is likely to be exhibited. As mentioned above, in the water-repellent regenerated cellulose fiber, the acidic group is bonded to the isocyanate compound, and even when the fiber surface is heated to a low temperature of 40°C or higher and 110°C or lower, the non-fluorine-based water repellent fiber remains intact. It has the effect of improving surface fixability and imparting ammonia deodorizing properties and pH buffering properties to regenerated cellulose fibers. In the present invention, the total amount of one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups is measured and calculated as described below.

The non-fluorine water repellent is not particularly limited, but for example, a hydrocarbon water repellent is preferred. As the hydrocarbon water repellent, for example, a hydrocarbon water repellent made of a polymer containing a (meth)acrylic ester as a basic monomer unit in which the hydrocarbon group exists via an ester bond and has 12 or more carbon atoms. It is preferable to use a liquid solution. The number of carbon atoms in the hydrocarbon group is more preferably 24 or less, and even more preferably 21 or less. The hydrocarbon group may be linear or branched, saturated or unsaturated hydrocarbon, and further may have an alicyclic or aromatic ring. You may do so. Among these, those that are linear are preferable, and those that are linear alkyl groups are more preferable. In this specification, (meth)acrylic ester means acrylic ester and/or methacrylic ester.

The amount of the (meth)acrylic acid ester monomer is preferably 80% by mass or more and 100% by mass or less based on the total amount of monomer units constituting the polymer. Further, the weight average molecular weight of the hydrocarbon water repellent is preferably 100,000 or more, more preferably 500,000 or more. The hydrocarbon water repellent may be a copolymer of acrylic ester and methacrylic ester.

The hydrocarbon water repellent can be used as a water repellent composition in which hydrocarbon water repellent particles are dispersed in water. The water repellent composition may contain a surfactant and an organic solvent. As such a water repellent composition, for example, commercial products such as NeoSeed NR series (manufactured by NICCA CHEMICAL CO., LTD.) may be used.

In the water-repellent regenerated cellulose fiber, the amount of the non-fluorine-based water repellent applied is, for example, preferably 0.1% by mass or more and 10% by mass or less, and 0.2% by mass based on 100% by mass of cellulose. It is more preferably 8% by mass or less, even more preferably 0.3% by mass or more and 6% by mass or less, and even more preferably 0.5% by mass or more and 2% by mass or less. When the amount of the non-fluorine water repellent applied is within the above range, the water repellency is good and the fibers are less likely to become rigid.

The non-fluorine water repellent may be used alone or in an appropriate combination of two or more.

The crosslinking agent is not particularly limited, but for example, it is preferable to use an isocyanate compound from the viewpoint of easily fixing the non-fluorine water repellent to the fiber surface. As the isocyanate compound, for example, a crosslinking agent such as a compound having an isocyanate group and a compound having a blocked isocyanate group can be used.

Examples of compounds having an isocyanate group include monoisocyanates such as butyl isocyanate, phenyl isocyanate, tolyl isocyanate, and naphthalene isocyanate, diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, tetramethylxylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate, and isocyanurate rings thereof. Examples include trimers and trimethylolpropane adducts.

Examples of the compound having a blocked isocyanate group include compounds obtained by protecting the isocyanate group of the above compound having an isocyanate group with a blocking agent. Blocking agents used at this time include organic blocking agents such as secondary or tertiary alcohols, active methylene compounds, phenols, oximes, and lactams, and bisulfite such as sodium bisulfite and potassium bisulfite. Examples include salt. In blocked isocyanate groups, highly reactive isocyanate groups are masked, and the blocks are usually dissociated by heat treatment at 120 to 180°C. Since it has one or more selected acidic groups, it is estimated that the blocks dissociate at a low temperature of 40° C. or higher and 110° C. or lower on the fiber surface. Therefore, the blocked isocyanate groups exist in a dissociated state on the surface of the water-repellent regenerated cellulose fiber.

In the water-repellent regenerated cellulose fiber, the amount of the isocyanate-based compound attached is, for example, preferably 0.010% by mass or more and 5.0% by mass or less, and 0.020% by mass or more based on 100% by mass of cellulose. It is more preferably 3.0% by mass or less, even more preferably 0.03% by mass or more and 2.0% by mass or less, even more preferably 0.05% by mass or more and 1.0% by mass or less. preferable. When the amount of the non-fluorine water repellent applied is within the above range, the durability of water repellency (hereinafter also referred to as durable water repellency) will be good and the fibers will not easily become rigid.

The crosslinking agents such as the isocyanate compounds may be used alone or in an appropriate combination of two or more.

The mass ratio of the non-fluorine water repellent to the isocyanate compound (non-fluorine water repellent: isocyanate compound) is not particularly limited, but for example, from the viewpoint of improving water repellency and its durability, it is 3: The ratio is preferably 1 or more and 7:1 or less, more preferably 4:1 or more and 6:1 or less.

The water-repellent fabric of the present invention has highly durable water repellency by containing the water-repellent regenerated cellulose fibers. The water-repellent fabric may be a woven fabric or a knitted fabric. The structure of the woven or knitted fabric is not particularly limited. For example, for knitted fabrics, circular knitting, flat knitting, warp knitting (tricot), etc. are preferable, and for woven fabrics, plain weave, twill weave, satin weave, etc. are preferable because they tend to exhibit the soft texture effect of cellulose fibers.

The water-repellent fabric may be composed only of the water-repellent regenerated cellulose fibers, or may contain other fibers. Examples of other fibers include regenerated cellulose fibers other than the water-repellent regenerated cellulose fibers, natural fibers, synthetic fibers, and the like. Examples of other regenerated cellulose fibers include rayon, cupro, solvent-spun cellulose, and polynosic. Examples of natural fibers include cotton, hemp, wool, silk, and the like. Examples of synthetic fibers include acrylic fibers, polyester fibers, polyamide fibers, polyolefin fibers, and polyurethane fibers. The synthetic fiber may be a single fiber or a composite fiber.

The water-repellent fabric preferably contains the water-repellent regenerated cellulose fibers in an amount of 10% by mass or more, more preferably 20% by mass or more, and even more preferably 25% by mass or more. If the content of the water-repellent regenerated cellulose fibers is low, there is a possibility that the fibers will be less able to exhibit their water-repellent properties. The upper limit of the content of the water-repellent regenerated cellulose fibers is not particularly limited, and can be determined as appropriate depending on the use of the fabric. If a soft texture is required, it may be composed of 100% by mass of water-repellent regenerated cellulose fibers, or other regenerated cellulose fibers and/or natural fibers may be used as other fibers. In the case of blended cotton with other hydrophilic regenerated cellulose fibers and/or natural fibers, water-repellent regenerated cellulose fibers range from 50% by mass to 90% by mass, and other regenerated cellulose fibers and/or natural fibers from 50% to 10% by mass. Water-repellent regenerated cellulose fibers may contain 60% to 90% by mass of water-repellent regenerated cellulose fibers, other regenerated cellulose fibers and/or natural fibers of 40% to 10% by mass, water-repellent regenerated cellulose fibers. It may contain 70% by mass or more and 90% by mass or less, and 30% by mass or more and 10% by mass or less of other regenerated cellulose fibers and/or natural fibers. If firmness, etc. is required, water-repellent regenerated cellulose fibers may contain 10% by mass or more and 50% by mass or less, synthetic fibers from 50% by mass or more and 90% by mass or less, and water-repellent regenerated cellulose fibers from 20% by mass or more and 45% by mass or less. , may contain 55% by mass or more and 80% by mass or less of synthetic fibers, 25% by mass or more and 40% by mass or less of water-repellent regenerated cellulose fibers, and 60% by mass or more and 75% by mass or less of synthetic fibers.

The water-repellent fabric is dyed with a reactive dye. By using a reactive dye, the color fastness of the water-repellent fabric, particularly the sweat fastness, is increased. The reactive dye will be explained in detail later.

The water-repellent fabric has a contact angle with water of 90° or more, preferably 100° or more, and more preferably 110° or more. When the contact angle with water is within the above range, durable water repellency is excellent.

From the viewpoint of improving water repellency, the water-repellent fabric preferably has a surface tension of 72.75 mN/m or less, more preferably 58.85 mN/m or less, and still more preferably 38.50 mN/m or less. be. Although the lower limit of the surface tension of the water-repellent fabric is not particularly limited, for example, from the viewpoint of hydrophilic treatment, it is preferably 20 mN/m or more, and more preferably 25 mN/m or more.

The basis weight of the water-repellent fabric is not particularly limited, and can be determined as appropriate depending on the use and the like. For example, in the case of knitted fabrics, from the viewpoint of wearability such as lightness, the basis weight is preferably 450 g/m ² or less, more preferably 400 g/m ² or less, and 300 g/m ² or less. It is more preferable, and it is particularly preferable that it is 200 g/m ² or less. Further, the water-repellent fabric is not particularly limited, but preferably has a basis weight of 50 g/m ² or more from the viewpoint of heat retention and the like.

The water-repellent fabric is not particularly limited, but for example, a non-fluorine-based repellent is applied to the fiber surface of regenerated cellulose fibers containing a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups using a crosslinking agent. A step of obtaining a water-repellent regenerated cellulose fiber by combining a water agent, a step of obtaining a water-repellent fabric containing the water-repellent regenerated cellulose fiber, and a hydrophilic treatment by applying water or an aqueous solution containing a surfactant to the water-repellent fabric. Preferably, the fabric is produced by a step of dyeing the hydrophilized fabric with a reactive dye, a step of drying the dyed fabric, and the like. A water-repellent fabric with no uneven dyeing, high color fastness, and excellent durable water repellency can be obtained.

The water-repellent regenerated cellulose fibers are not particularly limited, but for example, a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups is added to a viscose stock solution (raw material viscose) containing cellulose. A viscose liquid for spinning is prepared by mixing, the viscose liquid for spinning is extruded through a nozzle, and the viscose liquid is coagulated and regenerated to form a viscose rayon thread, and the viscose rayon thread is treated with an isocyanate compound and a non-fluorine water repellent. It can be produced by treating with a water-repellent treatment liquid containing a water-repellent agent and then heat-treating.

The raw material viscose may contain, for example, cellulose in a range of 7% by mass to 10% by mass, sodium hydroxide in a range of 5% by mass to 8% by mass, and carbon disulfide in a range of 2% by mass to 3.5% by mass. At this time, additives such as ethylenediaminetetraacetic acid (EDTA) and titanium dioxide may be used as necessary. The temperature of the raw material viscose is preferably kept at 18°C or higher and 23°C or lower.

The amount of the compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups may be 1% by mass or more and 35% by mass or less based on 100% by mass of cellulose in the raw material viscose. It is preferably 3% by mass or more and 30% by mass or less, and even more preferably 5% by mass or more and 25% by mass or less. Within the above range, a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups can be effectively kneaded into the fibers while increasing the fiber strength.

The viscose rayon yarn can be produced using, for example, a normal circular nozzle. As the spinning nozzle, it is preferable to use a circular nozzle having a diameter of 0.05 mm or more and 0.12 mm or less and a hole number of 1000 or more and 20000 or less, although it depends on the desired production volume. Alternatively, a nozzle with an irregular cross section may be used. Using the spinning nozzle, the viscose liquid for spinning is extruded into a spinning bath to be spun and coagulated and regenerated. The spinning speed is preferably in the range of 30 m/min or more and 80 m/min or less. Further, the stretching ratio is preferably 39% or more and 55% or less. Here, the stretching ratio indicates how high the sliver speed after stretching is when the sliver speed before stretching is 100. In terms of magnification, before stretching it is 1, and after stretching it is 1.39 times or more and 1.55 times or less.

The spinning bath (Mueller bath) is, for example, a strong acid containing sulfuric acid of 95 g/L or more and 130 g/L or less, zinc sulfate of 10 g/L or more and 17 g/L or less, and sodium sulfate (Salt salt) of 290 g/L or more and 370 g/L or less. Preferably, a sex bath is used. A more preferable sulfuric acid concentration is 95 g/L or more and 120 g/L or less.

The viscose rayon yarn (regenerated cellulose fiber) obtained as described above is cut into a predetermined length and usually subjected to a scouring treatment. The scouring step can generally be performed in the order of hot water treatment, water washing, hydrosulfurization treatment (desulfurization), bleaching, pickling, and water washing. Note that bleaching and pickling may be omitted.

If necessary, the rayon fiber yarn after the scouring process may be subjected to a pH adjustment treatment to adjust the pH of the fiber to 8.0 or less. The pH adjustment process can be performed by immersing the fibers in a buffer solution with a pH of 6.0 or less. The bath ratio during immersion is not particularly limited, but is preferably 1:10 or more and 1:30 or less, more preferably 1:15 or more and 1:25 or less. The immersion time is not particularly limited, but is preferably 0.5 minutes or more and 50 minutes or less, more preferably 1 minute or more and 20 minutes or less. The pH adjusting buffer is not particularly limited, and for example, general buffer solutions such as acetic acid-sodium acetate buffer can be used, but it is preferable that the buffer solution contains sodium. . After being immersed in a pH adjusting buffer, it may be washed with water and then dried.

In the regenerated cellulose fiber (before water repellent finishing), the amount of H-type carboxyl groups and/or H-type sulfonic acid groups is preferably 0.20 mmol or more and 1.60 mmol/g or less, more preferably 0.30 mmol. /g or more and 1.50 mmol/g or less, more preferably 0.35 mmol/g or more and 1.40 mmol/g or less. Further, in the regenerated cellulose fibers, the amount of salt-type carboxyl groups and/or salt-type sulfonic acid groups is preferably 1.0 mmol/g or less, more preferably 0.35 mmol/g or less, and even more preferably It is 0.015 mmol/g or more and 0.20 mmol/g or less.

In the regenerated cellulose fiber (before water repellent finishing), the ratio of the amount of H-type carboxyl groups and/or H-type sulfonic acid groups to the total amount of carboxyl groups and/or sulfonic acid groups is 45% or more and 100% or less. It is preferably 80% or more and 98% or less, and even more preferably 90% or more and 95% or less. When the ratio of the amount of the H-type carboxyl group and/or the H-type sulfonic acid group is within the above-mentioned range, the carboxyl group and/or sulfonic acid group and the isocyanate group are likely to bond in the water repellent processing step described below, and The carboxyl group and/or sulfonic acid group acts as an acid catalyst, and the amine produced by the efficient reaction of the isocyanate group with water becomes more likely to undergo various side reactions, thereby improving durable water repellency.

After the scouring process, water repellent treatment is performed. First, the viscose rayon yarn is treated with a water repellent treatment solution containing a crosslinking agent such as an isocyanate compound and a non-fluorine water repellent to attach the isocyanate compound and the non-fluorine water repellent. The treatment method using the water-repellent treatment liquid is not particularly limited, and examples thereof include dipping, spraying, shower coating, and the like. The treatment with the water repellent treatment liquid is carried out under conditions where the moisture content of the viscose rayon yarn is 100% by mass or more and 180% by mass or less, from the viewpoint of easily adhering the isocyanate compound and the non-fluorine water repellent to the fibers. It is preferable to carry out under conditions where the moisture content is 120% by mass or more and 150% by mass or less.

In the water repellent treatment liquid, the non-fluorine water repellent and the isocyanate compound are dispersed in a solvent such as water. The concentration of the non-fluorine water repellent in the treatment liquid is not particularly limited, but is preferably 0.15% by mass or more and 40% by mass or less. More preferably, it is 0.35% by mass or more and 35% by mass or less. When the concentration of the treatment liquid is within the above range, it is easy to adjust the amount of the non-fluorinated water repellent and isocyanate compound attached, and the temperature of the fiber surface can be adjusted to a low temperature when solvents such as water are evaporated during heat treatment. Easy and desirable.

The amount of the non-fluorine water repellent used can be adjusted as appropriate depending on the degree of water repellency required, but the amount of the non-fluorine water repellent (as a water repellent) Even when a water repellent composition is used, it is preferable to adjust the content of non-fluorine water repellent (only non-fluorine water repellent) to 0.1% by mass or more and 10% by mass or less, and 0.2% by mass or more and 8.0% by mass or less. It is more preferable to adjust the amount to % by mass or less. When the amount of the non-fluorine water repellent applied is within the above range, water repellency can be easily imparted and the softness of the regenerated cellulose fibers can be maintained.

The amount of the isocyanate compound (for example, a crosslinking agent such as a compound having an isocyanate group and a compound having a blocked isocyanate group) to be used is not particularly limited, but from the viewpoint of easily maintaining the softness of the regenerated cellulose fiber, It is preferably 0.010% by mass or more and 5.0% by mass or less, and more preferably 0.02% by mass or more and 3.0% by mass or less, based on 100% by mass of the fibers.

In the water repellent treatment liquid, the mass ratio of the non-fluorinated water repellent to the isocyanate compound (non-fluorinated The ratio of fluorine water repellent to isocyanate compound is preferably 3:1 or more and 7:1 or less, more preferably 4:1 or more and 6:1 or less.

Next, by heat-treating the fibers, a non-fluorine water repellent is bonded to the fiber surface of the regenerated cellulose fibers using a crosslinking agent. The heat treatment is preferably performed under conditions such that the temperature of the fiber surface is 40° C. or higher and 110° C. or lower. A more preferable lower limit of the heat treatment temperature (actual temperature) is that the fiber surface is 50° C. or higher, and an even more preferable lower limit is that the fiber surface is 60° C. or higher. More preferably, the upper limit of the actual temperature is such that the fiber surface is less than 100°C, still more preferably 95°C or less, and still more preferably 90°C or less. When the heat treatment temperature is within the above range, the isocyanate compound and the non-fluorine water repellent are firmly bonded to the fibers, and deterioration of the fibers due to heat, such as yellowing of the fibers, can be suppressed. When the water-repellent treatment liquid contains water, the drying treatment performed to remove water can be heat treatment.

After the water repellent treatment, an oil agent may be applied as necessary to the extent that the water repellency is not impaired.

The water-repellent finishing of the present invention was explained above using an example in which it is carried out during the manufacturing process of rayon yarn, but the water-repellent finishing is carried out after making a spun yarn containing rayon fiber, a rayon filament yarn, or a fabric containing rayon fiber. You can go.

The water-repellent regenerated cellulose fiber is not particularly limited, but preferably has a single fiber fineness of 0.3 dtex or more and 8.0 dtex or less, for example. More preferably, it is 0.6 dtex or more and 6.0 dtex or less, and still more preferably 0.7 dtex or more and 3.6 dtex or less. When the single fiber fineness is less than 0.3 dtex, single fiber breakage tends to occur during drawing. If the single fiber fineness exceeds 8.0 dtex, the regenerated state of the fibers tends to be poor, and the hue of the fibers may deteriorate.

The water-repellent regenerated cellulose fiber has a whiteness of Hw80 or more, and from the viewpoint of retaining the texture of cellulose, preferably Hw80 or more and Hw90 or less. In the case of general regenerated cellulose fibers, it is necessary to react with a crosslinking agent at 120°C or higher when applying water repellent treatment, and at 170°C or higher to improve water repellency durability. The temperature decreases significantly (Hw less than 80). In the present invention, since regenerated cellulose containing specific acidic groups is used, deterioration of cellulose can be suppressed, and as a result, whiteness tends to hardly decrease.

The water-repellent regenerated cellulose fiber preferably has a standard tensile strength (hereinafter also referred to as dry strength) of 1.5 cN/dtex or more and 3.0 cN/dtex or less, as measured according to JIS L 1015. More preferably, it is 1.7 cN/dtex or more and 2.7 cN/dtex or less. The tensile strength when wet (hereinafter also referred to as wet strength) is preferably 0.6 cN/dtex or more and 2.0 cN/dtex or less. More preferably, it is 0.8 cN/dtex or more and 1.8 cN/dtex or less.

The water-repellent regenerated cellulose fiber preferably has a standard elongation rate (hereinafter also referred to as dry elongation) of 15% or more and 25% or less, as measured according to JIS L 1015. More preferably, it is 16% or more and 24% or less. The elongation rate when wet (hereinafter also referred to as wet elongation) is preferably 15% or more and 40% or less. More preferably, it is 18% or more and 35% or less.

When the tensile strength and elongation rate are within the above ranges, spinnability is good and product strength tends to be good.

Normally, when applying water repellency to regenerated cellulose fibers, it is necessary to react with a crosslinking agent at 120°C or higher, and to improve water repellency durability, it is necessary to react with a crosslinking agent at 170°C or higher. As the water agent forms a film and cross-links strongly, the rigidity and strength of the entire fiber increases in standard conditions (dry state), but the strength of the cellulose itself decreases due to deterioration of the amorphous parts of cellulose due to heat. There is. Therefore, in addition to the strength of cellulose itself decreasing due to swelling due to water and cleavage of hydrogen bonds in amorphous portions, as in the case of humidity, the wet strength tends to decrease significantly due to the influence of deterioration due to heat. In the present invention, the cellulose has one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups, and can be treated with water repellency at a low temperature of 100°C or less, so the fibers are cross-linked. While the rigidity and strength of cellulose increases, there is less damage to the cellulose itself due to heat, and there is a tendency for the wet strength to decrease less.

The water-repellent regenerated cellulose fiber preferably has a standard apparent Young's modulus (hereinafter also referred to as dry Young's modulus (DY)) measured according to JIS L 1015 of 3500 MPa or more and 8500 MPa or less. More preferably, it is 4000 MPa or more and 8000 MPa or less. The apparent Young's modulus when wet (hereinafter also referred to as wet Young's modulus (WY)) is preferably 800 MPa or more and 1300 MPa or less. More preferably, it is 900 MPa or more and 1200 MPa or less. When the apparent Young's modulus is within the above range, appropriate stiffness can be imparted to the fiber while maintaining the softness of the fiber itself.

The ratio of wet/standard (wet/dry) in the apparent Young's modulus is expressed as a factor for firmly binding the water repellent while suppressing deterioration of cellulose itself, and is expressed by the following formula.
Wet and dry Young's modulus ratio = (WY/DY) x 100 (1)
The apparent Young's modulus indicates the initial tensile stiffness of the fiber, and the dry Young's modulus (DY) tends to increase due to the strength of the cellulose itself and the water repellent agent due to cross-linking. Young's modulus (WY) tends to decrease due to the swelling of cellulose due to water and the breaking of hydrogen bonds in the amorphous portion, which reduce the initial tensile stiffness, and the effect of deterioration of the amorphous portion due to heat. It is in. Therefore, as in the present invention, by suppressing the deterioration of cellulose, the decrease in WY is suppressed, and as a result, WY/DY tends to increase. WY/DY is preferably 12.0 or more. More preferably, it is 12.5 or more.

Next, a water-repellent fabric containing water-repellent regenerated cellulose fibers is obtained. For example, a knitted or woven fabric is produced by a known method. For example, a spun yarn containing water-repellent regenerated cellulose fibers can be produced by a conventional method, and a knitted fabric or a woven fabric can be produced using the spun yarn by a conventional method. The count of the spun yarn is not particularly limited, but may be in the range of 5 to 100S in English cotton count, preferably 10 to 90S, more preferably 15 to 85S, and even more preferably 20 to 85S. It is 80S.

Next, the water-repellent fabric is subjected to a hydrophilic treatment by applying water or an aqueous solution containing a surfactant. Normally, when fabrics containing water-repellent cellulose fibers cross-linked with water-repellent agents are immersed in a dye bath and dyed, the dyeing becomes uneven, the color fastness decreases, and the water-repellent performance decreases. . In the present invention, since a non-fluorine-based water repellent is used, when water or an aqueous solution containing a surfactant is applied to a water-repellent fabric, the orientation of the water-repellent groups of the non-fluorine-based water repellent on the surface of the fibers is disturbed. can temporarily make water-repellent fabric hydrophilic. In addition, as mentioned above, by using a non-fluorine water repellent and making the water-repellent regenerated cellulose fibers contain a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups, the fiber surface can be improved. The fixing properties of the non-fluorine-based water repellent bonded to the dye are improved, and the color fastness and water repellency are not reduced.

When the hydrophilization treatment is performed with water, there are no particular limitations, but for example, from the viewpoint of enhancing the hydrophilization effect, it is preferable to immerse in water at a temperature of 20°C or higher and 70°C or lower, more preferably water at a temperature of 30°C or higher and 60°C or lower. Soak in. The immersion time is preferably 5 minutes or more, more preferably 10 minutes or more, and even more preferably 20 minutes or more, from the viewpoint of enhancing the hydrophilic effect. Further, from the viewpoint of productivity, it is preferable to soak for 40 minutes or less, and more preferably for 30 minutes or less. If desired, high pressure water may be used and the water may be stirred during soaking. The bath ratio is preferably 1:10 to 1:100 (water repellent fabric: water), more preferably 1:15 to 1:80, and even more preferably 1:20 to 1:70. preferable. The water may be purified water, tap water, industrial water, or a mixture thereof.

When the hydrophilization treatment is performed with an aqueous solution containing a surfactant, it is not particularly limited, but for example, from the viewpoint of enhancing the hydrophilization effect, it is preferable to immerse in an aqueous solution containing a surfactant at a temperature of 30° C. or higher and 70° C. or lower. It is more preferable to immerse it in an aqueous solution containing a surfactant at a temperature of 65°C or higher. The immersion time is preferably 5 minutes or more, and more preferably 10 minutes or more, for example, from the viewpoint of enhancing the hydrophilic effect. Further, from the viewpoint of productivity, it is preferable to soak for 30 minutes or less, and more preferably for 20 minutes or less. Further, if necessary, a high-pressure aqueous solution containing a surfactant may be used, and the aqueous solution containing a surfactant may be stirred during immersion. The bath ratio is preferably 1:10 to 1:100 (water repellent fabric: aqueous solution containing surfactant), more preferably 1:15 to 1:80, and 1:20 to 1:70. It is more preferable that After treating the aqueous solution containing the surfactant, it may be dehydrated and then further treated with water. The water used in the aqueous solution containing the surfactant may be purified water, tap water, industrial water, or a mixture thereof.

The surfactant is not particularly limited as long as it can make the fabric hydrophilic. For example, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, etc. can be used. In the subsequent dyeing process, from the viewpoint of increasing the permeability of the reactive dye, the surfactant preferably contains one or more selected from the group consisting of nonionic surfactants and anionic surfactants; More preferably, it contains a surfactant.

Examples of the nonionic surfactants include glycerin fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, alkyldiethanolamine, hydroxyalkyl monoethanolamine, polyoxyethylene alkylamine, polyoxyethylene alkylamine fatty acid ester, and polyoxyethylene alkyl amine. Examples include oxyethylene sorbitan fatty acid esters and alkyl diethanolamides. Among these, polyoxyethylene alkyl ether is preferred from the viewpoint of improving the hydrophilic effect and the permeability of reactive dyes.

The polyoxyethylene alkyl ether is not particularly limited, but for example, the number of carbon atoms in the alkyl group is preferably 6 or more and 22 or less, more preferably 8 or more and 20 or less, and 10 or more and 18 or less. is even more preferable. Further, the average number of moles of ethylene oxide added is preferably 1 mol or more and 60 mols or less, more preferably 3 mols or more and 40 mols or less, and even more preferably 5 mols or more and 20 mols or less.

The anionic surfactant is not particularly limited, and includes, for example, α-sulfo fatty acid ester salts, α-olefin sulfonates, alkyl ether sulfate salts, higher fatty acid salts, and linear or branched alkyl sulfate ester salts. , carboxylic acid type anionic salts such as alkanesulfonates having alkyl groups, alkyl ether carboxylates, polyoxyalkylene ether carboxylates, alkyl amide ether carboxylates or alkenyl amide ether carboxylates, acylamino carboxylates, etc. Examples include surfactants, phosphate ester type anionic surfactants such as alkyl phosphate ester salts, polyoxyalkylene alkyl phosphate ester salts, polyoxyalkylene alkylphenyl phosphate ester salts, glycerin fatty acid ester monophosphate ester salts, etc. It will be done. Among these, one or more selected from the group consisting of α-sulfo fatty acid ester salts, α-olefin sulfonates, and alkyl ether sulfate ester salts are preferred from the viewpoint of increasing the hydrophilic effect and the permeability of reactive dyes.

Examples of the salt form of the anionic surfactant include alkali metal salts such as sodium salt and potassium salt; alkaline earth metal salts such as magnesium salt and calcium salt; monoethanolamine salt (monoethanolammonium), diethanolamine salt ( Alkanolamine salts such as diethanolammonium) and triethanolamine salt (triethanolammonium); ammonium salts, etc., and alkali metal salts are preferred.

The cationic surfactant is not particularly limited, and includes, for example, aliphatic amine or its quaternary ammonium salt, fatty acid amide amine salt, alkyl trialkylene glycol ammonium salt, acyl guanidine derivative, mono-N-long chain acyl basic Examples include amino acid-based cationic surfactants such as amino acid lower alkyl ester salts, alkylbenzalkonium salts, alkylpyridinium salts, imidazolinium salts, and the like.

The amphoteric surfactant is not particularly limited, and includes, for example, alkyl betaine type, alkylamide betaine type, imidazoline type, alkylaminosulfone type, alkylaminocarboxylic acid type, alkylamidocarboxylic acid type, amide amino acid type, or phosphoric acid type. Examples include types.

The surfactants mentioned above may be used alone or in combination of two or more.

In the aqueous solution containing the surfactant, although not particularly limited, the concentration of the surfactant is preferably 0.1 g/L or more and 1.0 g/L or less, more preferably 0.15 g/L or more and 0.8 g /L or less. When the concentration of the surfactant is 0.1 g/L or more, it is easy to exhibit a hydrophilic effect. When the concentration of the surfactant is 1.0 g/L or less, water repellency is not inhibited.

After the hydrophilization treatment, the moisture content of the hydrophilized fabric is preferably adjusted to 100% by mass or more and 250% by mass or less, and 150% by mass or more and 200% by mass or less by performing dehydration or the like. It is preferable to adjust so that When the moisture content is within the above-mentioned range, the temporarily hydrophilic property of the hydrophilized fabric is well expressed, and uneven dyeing can be more effectively eliminated in the subsequent dyeing process.

Next, the hydrophilized fabric is dyed with a reactive dye. The dyeing method is not particularly limited, and any known method can be used. For example, dyeing can be performed by dipping a hydrophilized fabric in a dyeing solution containing a reactive dye and a dyeing aid. The bath ratio can be, for example, in the range of 1:10 to 1:50. The immersion time can be appropriately determined depending on the type of reactive dye used, and may be, for example, 50 minutes or more and 100 minutes or less.

The reactive dye is not particularly limited, but includes, for example, reactive dyes with a high directivity level and medium to high reactivity level, such as Sumifix (manufactured by Sumitomo Chemical Co., Ltd.) and Remazol (manufactured by Dystar Co., Ltd.). company), K-Pizol (manufactured by Kiwa Chemical Co., Ltd.), Sumifix Supra (manufactured by Sumitomo Chemical Co., Ltd.), Revafix (manufactured by Dystar Co., Ltd.), Procion (manufactured by Mitsui BASF Dye Co., Ltd.), Cibacron (manufactured by Ciba Specialty Chemicals Co., Ltd.) (manufactured by Mitsui BASF Dye Co., Ltd.), Bacilene (manufactured by Mitsui BASF Dye Co., Ltd.), Kayacion (manufactured by Nippon Kayaku Co., Ltd.), and other reactive dyes can be used. These reactive dyes may be used alone or in combination of two or more. The amount of reactive dye to be used may be appropriately determined depending on the desired hue.

As the dyeing aid, an alkaline compound may be used alone, or a neutral salt and an alkaline compound may be used in combination. Examples of alkaline compounds include caustic soda, soda carbonate, and baking soda. Examples of neutral salts include common salt, mirabilite, and the like. The amount to be used can be determined according to the standard dyeing method using reactive dyes.

After the dipping treatment is completed, washing with water or hot water can be performed in the same manner as in known dyeing. Further, soaping may be performed as necessary.

After dyeing is completed, a drying process is performed. In the hydrophilic treatment, the water-repellent groups of the non-fluorine-based water repellent on the fiber surface of the water-repellent cellulose fibers in the water-repellent fabric are disturbed, resulting in temporary hydrophilization, which is then uniformly coated with reactive dye in the dyeing process. On the other hand, by drying after dyeing, the water-repellent groups of the non-fluorine-based water repellent are oriented outward, and water repellency is restored. Drying is not particularly limited, and can be performed under the same conditions as normal drying after dyeing. For example, from the viewpoint of improving washing durability of water repellency, drying is preferably performed at a temperature of 60°C or higher and 180°C or lower, more preferably 80°C or higher and 170°C or lower, and 90°C or higher. It is more preferable to carry out at a temperature of 160°C or lower, and may be carried out at a temperature of 100°C or lower. Further, the drying time is not particularly limited as long as it is a time for water repellency to recover, but for example, the drying time may be 5 seconds or more and 15 minutes or less, 5 seconds or more and 10 minutes or less, and 5 seconds or more and 5 minutes or less. You may go.

The water-repellent fabric may be refined and bleached before dyeing. In this case, the hydrophilic treatment may be performed simultaneously with the refining and bleaching treatments, or the hydrophilic treatment may be performed after the refining and bleaching treatments. From the viewpoint of further reducing dyeing unevenness, it is preferable to perform a hydrophilic treatment after the refining and bleaching treatments.

The water-repellent fabric can be used for clothing, industrial base materials, and the like. Examples of clothing include underwear, underwear, shirts, jumpers, sweaters, pants, training wear, tights, belly bands, mufflers, hats, gloves, socks, earmuffs, and the like. Examples of industrial base materials include carpets, bedding, furniture, and the like.

Hereinafter, the present invention will be explained in more detail with reference to Examples. The present invention is not limited to the following examples.

First, the measurement methods used in Examples and Comparative Examples will be explained.

(Measurement of weight average molecular weight)
The weight average molecular weight (Mw) was determined by GPC (gel permeation chromatography) under the following conditions. When calculating the weight average molecular weight, the part having a molecular weight of 300 or more on the chart obtained by GPC was defined as a polymer.
Column: GF-7MHQ (manufactured by Showa Denko Co., Ltd.).
Mobile phase: Add pure water to 34.5 g of disodium hydrogen phosphate dodecahydrate and 46.2 g of sodium dihydrogen phosphate dihydrate (both reagent grade) to make a total amount of 5,000 g, and then Aqueous solution filtered through a 0.45 micron membrane filter.
Detector: UV 214 nm (manufactured by Nippon Waters Co., Ltd., Model 481).
Pump: L-7110 (manufactured by Hitachi, Ltd.).
Flow rate: 0.5mL/min.
Temperature: 35℃.
Calibration curve: Sodium polyacrylate standard sample (manufactured by Sowa Kagaku Co., Ltd.).

(Measurement of total amount of carboxyl groups)
(1) 1.2 g of a sample was immersed in 50 mL of a 1 mol/L hydrochloric acid aqueous solution (pH 0.1), stirred, and left for 5 minutes. Thereafter, the solution was stirred again to adjust the pH of the aqueous solution to 2.5. As a result, all carboxyl groups in the sample (fiber) exist as H-type. Next, the sample was washed with water and dried in a constant temperature blow dryer at 105° C. for 2 hours to make it completely dry. By washing the sample with water, all excess hydrochloric acid adhering to the fibers will be removed.
(2) 100 mL of ion-exchanged water, 0.4 g of sodium chloride, and 20 mL of a 0.1 mol/L aqueous sodium hydroxide solution were placed in a beaker.
(3) Precisely weigh 1 g of the sample prepared in (1) [W1 (g)], cut it into small pieces that will not wrap around the stirrer, put it in the beaker prepared in (2), and stir with a stirrer for 15 minutes. did. As a result, all carboxyl groups in the sample (fiber) are converted into salt forms. The stirred sample was filtered by suction. 60 mL of the filtrate was taken and titrated with a 0.1 mol/L aqueous hydrochloric acid solution using phenolphthalein as an indicator to give a titration amount of X1 (mL).
(4) The total amount of carboxyl groups Y (mmol/g) was calculated based on the following formula. Thus, the amount of sodium hydroxide determined by subtracting the remaining amount of sodium hydroxide from the total amount of sodium hydroxide corresponds to the total amount of carboxyl groups in the sample (fiber).
Total amount of carboxyl groups Y (mmol/g) = [[(0.1×20)-(0.1×X1)]×(120/60)]/W1

(Measurement of the amount of H-type carboxyl groups and the amount of salt-type carboxyl groups)
(1) The sample was washed with water and dried at 105° C. for 2 hours in a constant temperature blow dryer to dry completely.
(2) 100 mL of ion-exchanged water, 0.4 g of sodium chloride, and 20 mL of a 0.1 mol/L aqueous sodium hydroxide solution were placed in a beaker.
(3) 1 g of the sample was accurately weighed [W2 (g)], cut into pieces to a size that would not wrap around the stirrer, placed in the beaker prepared in (2), and stirred with a stirrer for 15 minutes. The stirred sample was filtered by suction. 60 mL of the filtrate was taken and titrated with a 0.1 mol/L aqueous hydrochloric acid solution using phenolphthalein as an indicator to give a titration amount of X2 (mL).
(4) Based on the following formula, the amount Z (mmol/g) of H-type carboxyl groups, the amount U (mmol/g) of salt-type carboxyl groups, the ratio (%) of the amount of H-type carboxyl groups, and the salt-type carboxyl groups The proportion (%) of the amount was calculated.
Amount of H-type carboxyl group Z (mmol/g) = [{(0.1×20)-(0.1×X2)]×(120/60)]/W2
Amount of salt-type carboxyl groups U (mmol/g) = Total amount of carboxyl groups Y (mmol/g) - Amount of H-type carboxyl groups Z (mmol/g)
Ratio (%) of the amount of H-type carboxyl group = {Amount of H-type carboxyl group Z (mmol/g)}
/{total amount of carboxyl groups Y (mmol/g)}×100
Ratio (%) of the amount of salt-type carboxyl groups = {Amount U of salt-type carboxyl groups (mmol/g)}
/{total amount of carboxyl groups Y (mmol/g)]×100

(Contact angle of fabric with water)
(1) Ion-exchanged water was poured into a 25 mL buret (manufactured by As One) and set on a burette stand.
(2) The distance between the tip of the burette and the fabric was set to be 1 cm.
(3) One drop (0.049 mL) of ion-exchanged water was dropped, and the contact angle of the fabric with the water droplet was measured 10 seconds after landing on the water. The measurements were performed with n=2, and the contact angles on both the left and right sides of the water drop were measured and averaged.

(Surface tension of fabric)
(1) As shown in Table 1 below, ethanol and distilled water were mixed to prepare reagents with different ethanol concentrations and used as standards for surface tension.
(2) Reagents were dropped onto the measurement sample in order of decreasing concentration.
(3) The surface tension of the reagent when the contact angle was maintained at 90° or more after being allowed to stand for 30 seconds was taken as the reference value for the surface tension of the measurement sample. That is, the surface tension of the measurement sample is smaller than the reference value.

(washing fastness)
Measurement was carried out at the Kaken Test Center, a general incorporated foundation, in accordance with JIS L 0844 A-2.

(Sweat fastness)
Measurement was performed at Kaken Test Center, a general incorporated foundation, in accordance with JIS L 0848.

(washing process)
Washing treatment was performed 10 times according to the method specified in JIS L 0217 103 method.

(Example 1)
[Preparation of water-repellent regenerated cellulose fiber]
《Preparation of viscose liquid for spinning》
Aqueous solution of acrylic acid-maleic acid copolymer salt ("Aqualic TL400" manufactured by Nippon Shokubai Co., Ltd., an aqueous solution containing 40% by mass of sodium acrylic acid-maleic acid copolymer with a weight average molecular weight of 50,000, viscosity: 1990 mPa. s, the content of maleic acid in the sodium acrylic acid-maleic acid copolymer is 45% by mass), so that the acrylic acid-maleic acid copolymer salt is 5% by mass with respect to 100% by mass of cellulose, It was added to the raw material viscose and stirred and mixed using a mixer to prepare a viscose liquid for spinning. The temperature was kept at 20°C. The raw material viscose contained 8.5% by mass of cellulose, 5.7% by mass of sodium hydroxide, and 2.8% by mass of carbon disulfide. In addition, in the Examples and Comparative Examples, the viscosity was measured at 20° C. using a B-type viscometer manufactured by Tokyo Keiki Co., Ltd. Moreover, the weight average molecular weight of the compound containing a carboxyl group was measured and calculated as described below.
《Spinning process》
The obtained viscose liquid for spinning was spun by a two-bath tension spinning method at a spinning speed of 50 m/min and a drawing rate of 50% to obtain a viscose rayon yarn having a fineness of 1.4 dtex. As the first bath (spinning bath), a Mueller bath (50° C.) containing 100 g/L of sulfuric acid, 15 g/L of zinc sulfate, and 350 g/L of sodium sulfate was used. Further, a circular nozzle (pore diameter: 0.06 mm, number of holes: 4000) was used as a spinneret for discharging viscose.
《Scouring process》
The viscose rayon yarn obtained above was cut into fiber lengths of 38 mm, treated with hot water, washed with water, and desulfurized by showering with sodium hydrogen sulfide. The obtained treated cotton was washed again with water, bleached with sodium hypochlorite, pickled, and then washed with water. Thereafter, the fibers were squeezed using a compression roller so that the moisture content was 130%. In the regenerated cellulose fiber (before water-repellent finishing), the ratio of H-type carboxyl groups to the total amount of carboxyl groups was 94%, and the amount of H-type carboxyl groups was 0.53 mmol/g.
《Water repellent finishing》
First, a hydrocarbon water repellent composition (NeoSeed NR-158, manufactured by NICCA Chemical Co., Ltd.) was used as a non-fluorine water repellent, and a blocked isocyanate crosslinking agent (manufactured by NICCA Chemical Co., Ltd.) was used as an isocyanate compound. "NK Assist NY-30" (solid content concentration 40% by mass) was used to repel water by mixing the water repellent (water repellent particles):crosslinking agent (solid content) at a mass ratio of 5:1. A processing liquid was obtained. Next, the fibers obtained above with a moisture content of 130% were immersed in a water repellent treatment solution (50° C.) for 30 seconds. The bath ratio of fiber:water repellent treatment solution was 1:10. After that, the fibers were squeezed using a compression roller so that the adhesion rate of the water repellent (solid content) to the fibers was 1% by mass, and then dried for 10 minutes in a dryer set at 100°C. Obtained. The actual temperature at this time was 85°C. The total amount of carboxyl groups in the obtained water-repellent regenerated cellulose fiber was 0.52 mmol/g.

[Preparation of fabric]
A 30 count (30S) spun yarn was prepared using 100% by mass of fiber A. Using 100% by mass of the above-mentioned spun yarn, a tube-knitted yarn (basis weight: 130 g/m ² ) was produced by a conventional method.
The unscoured and unbleached fabric (tube knit) obtained above was immersed in an aqueous solution containing 0.1 g/L of JAFET standard combination detergent (combined with polyoxyethylene alkyl ether and sodium alpha olefin sulfonate). The mixture was stirred for 5 minutes (ratio 1:30), then dehydrated, and washed twice with water at a bath ratio of 1:30 to adjust the moisture content to about 100%. In addition, when the hydrophilized fabric was air-dried at room temperature (approximately 23°C), the contact angle with water was measured, and it was found to be smaller than the contact angle with water of the fabric before the hydrophilic treatment (the contact angle was 77°). ), it was confirmed that it was made hydrophilic.
The hydrophilized fabric obtained above (moisture content approximately 100%) was dyed in a reactive dyeing bath (42 g/L of sodium sulfate, 5 g/L of sodium carbonate, reactive dye: Sumifix Supra (Sumifix Supra) BLUE BRF (blue) 2.1% OWF composition) for 40 minutes at 25°C, dyeing was performed at a temperature of 50°C for 60 minutes. The bath ratio was 1:50. Thereafter, it was soaped with 0.5 g/L Senkanol C-100 (bath ratio 1:30) at a temperature of 60°C for 10 minutes, and then washed with hot water at 70°C for 10 minutes.
Next, the dyed fabric was treated at 150° C. for 10 seconds and dried.

(Comparative example 1)
A fabric was produced in the same manner as in Example 1, except that the fabric (tube knit) that had not been scoured or bleached was used as it was in the dyeing process without being subjected to hydrophilic treatment.

The washing fastness, sweat fastness, contact angle (also referred to as water repellency angle), and surface tension of the fabrics of Examples and Comparative Examples were measured as described above, and the results are shown in Table 2 below. In addition, the fabrics of Examples and Comparative Examples were visually observed for the presence or absence of uneven dyeing, and the results are shown in Table 2 below.

As can be seen from the results in Table 2, in the Examples, fabrics with no uneven dyeing and high fastness to washing and fastness to perspiration could be obtained. Moreover, the water repellency of the fabric was also good, and the washing durability of the water repellency was also good. On the other hand, in Comparative Example 1, uneven dyeing occurred because no hydrophilic treatment was performed before dyeing.

The fabric of the present invention can be used for clothing, industrial materials, and the like.

Claims (9)

A water-repellent fabric comprising water-repellent regenerated cellulose fibers,
The water-repellent regenerated cellulose fiber contains a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups, and has a crosslinking agent and a non-fluorine water repellent bonded to the fiber surface. ,
The water-repellent fabric is dyed with a reactive dye and has no uneven dyeing,
The water-repellent fabric is characterized in that the water-repellent fabric has a contact angle with water of 90° or more. The water-repellent fabric according to claim 1, wherein the non-fluorine water repellent is a hydrocarbon water repellent. The water-repellent fabric according to claim 1 or 2, wherein the carboxyl group-containing compound is one or more selected from the group consisting of polyacrylic acid and acrylic acid-maleic acid copolymer. The water- repellent fabric according to any one of claims 1 to 3, wherein the water-repellent fabric contains the water-repellent regenerated cellulose fibers in an amount of 50% by mass or more and 100% by mass or less. A method for producing a water-repellent fabric comprising water-repellent regenerated cellulose fibers, the method comprising:
A non-fluorinated water repellent is bonded to the fiber surface of regenerated cellulose fibers containing a compound containing one or more acidic groups selected from the group consisting of carboxyl groups and sulfonic acid groups using a crosslinking agent to obtain water-repellent regenerated cellulose fibers. process,
obtaining a water-repellent fabric containing the water-repellent regenerated cellulose fibers;
applying an aqueous solution containing water and/or a surfactant to the water-repellent fabric to make it hydrophilic;
a step of dyeing the hydrophilic treated water-repellent fabric with a reactive dye;
A method for producing a water-repellent fabric, comprising the step of drying the dyed fabric. 6. The method for producing a water-repellent fabric according to claim 5, wherein the hydrophilic treatment is performed immediately before the dyeing step. The method for producing a water-repellent fabric according to claim 5 or 6, wherein the drying is performed at a temperature of 60°C or higher. The method for producing a water-repellent fabric according to any one of claims 5 to 7, wherein the crosslinking agent is an isocyanate compound. The method for producing a water-repellent fabric according to any one of claims 5 to 8, wherein the surfactant includes one or more selected from the group consisting of nonionic surfactants and anionic surfactants.