Permeable treatment agents, permeable fibers, nonwoven fabrics and absorbent articles

Abstract

To provide a water-permeable treatment agent that can reduce the amount of liquid remaining on the surface material, a water-permeable fiber, a non-woven fabric and an absorbent article.SOLUTION: A water-permeable treatment agent contains a surface active agent (A) that has a solubility in 100 g of water at 25°C greater than 0.025 g and 0.05 g or less and has a surface tension of 35 mN / m or less measured at a temperature condition of 25°C after a lapse of 1 hour after diluting to 0.05 wt.% with water. The water-permeable treatment agent preferably further contains a surface active agent (B) that satisfies at least one of the solubility in 100 g of water at 25°C of over 0.05 g and the surface tension at 25°C when diluted to 0.05 wt.% with water of over 35 mN / m.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a water-permeable treatment agent, water-permeable fibers, a non-woven fabric, and an absorbent article.

Background Art

[0002] Absorbent articles such as paper diapers and sanitary products generally have a structure including a liquid-permeable surface material, a back sheet, and an absorbent body provided therebetween, and body fluids such as urine and blood are absorbed by the absorbent body through the surface material. In recent years, in absorbent articles, improvement in the performance of the absorbent body for repeatedly absorbing body fluids has been demanded, and in order to avoid discomfort, after absorbing body fluids, reducing the amount of remaining liquid on the surface material and improving the dryness have been studied. <​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0007] The present inventors have diligently studied to solve the above problems and have arrived at the present invention. Specifically, the present invention relates to a water-permeable treatment agent comprising a surfactant (A) having a solubility in 100g of water at 25°C greater than 0.025g and 0.05g or less, and a surface tension of 35mN / m or less measured at a temperature of 25°C after dilution to 0.05% by weight with water and elapsed for 1 hour; a water-permeable fiber having the water-permeable treatment agent attached to a hydrophobic fiber, wherein the proportion of the non-volatile component of the water-permeable treatment agent is 0.02 to 2 parts by weight per 100 parts by weight of the hydrophobic fiber; a nonwoven fabric containing the water-permeable fiber; and an absorbent article containing the nonwoven fabric. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a water-permeable treatment agent, water-permeable fibers, nonwoven fabrics, and absorbent articles that can reduce the amount of liquid remaining on the surface material. [Modes for carrying out the invention]

[0009] [Water permeability treatment agent] The water-permeable treatment agent of the present invention contains a surfactant (A) whose solubility in 100 g of water at 25°C is greater than 0.025 g and 0.05 g or less, and whose surface tension, measured at a temperature of 25°C after dilution to 0.05% by weight with water and elapsed for 1 hour, is 35 mN / m or less. By including the surfactant (A) in the water-permeable treatment agent, the amount of liquid remaining on the surface material can be reduced.

[0010] [Surfactant (A)] The solubility of surfactant (A) in 100g of water at 25°C is greater than 0.025g and less than or equal to 0.05g. From the viewpoint of reducing the amount of residual liquid, the solubility of surfactant (A) is preferably 0.026g or more, more preferably 0.03g or more, preferably 0.045g or less, and more preferably 0.04g or less. If the solubility of surfactant (A) is 0.025g or less, the effect of reducing the amount of residual liquid may not be sufficiently realized. In this invention, under conditions of a temperature of 25°C and a humidity of 40%RH, 0.005g of surfactant is added to 100g of deionized water while stirring with a stirrer, and the amount of surfactant dissolved at the point when it becomes insoluble [at least one of the following is observed: suspension, precipitation, sedimentation, and turbidity (transmittance of 95% or less)] is defined as the "solubility in 100g of water at 25°C". An example is given. For example, if the point at which the surfactant becomes insoluble is when 0.035g of surfactant is added, then the "amount of surfactant dissolved at the point of insolubleness" is 0.030g, and this amount of surfactant dissolved (0.030g) becomes the "solubility in 100g of water at 25°C".

[0011] The surface tension of surfactant (A), measured at a temperature of 25°C after diluting it to 0.05% by weight with water and allowing 1 hour to pass (hereinafter also referred to as "surface tension at 25°C when diluted to 0.05% by weight with water"), is 35 mN / m or less. From the viewpoint of reducing the amount of residual liquid, the surface tension of surfactant (A) is preferably 33 mN / m or less, more preferably 30 mN / m or less. The lower limit of the surface tension of surfactant (A) is not particularly limited, but is preferably 25 mN / m or more, more preferably 26 mN / m or more. In the present invention, the surface tension at 25°C when diluted to 0.05% by weight with water can be measured by the plate method (Wilhelmy method) using an automatic surface tensimeter (manufactured by Kyowa Interface Science Co., Ltd.) at a temperature of 25°C and a humidity of 40% RH, after diluting it to 0.05% by weight with water and allowing 1 hour to pass. When the diluted solution is diluted to 0.05% by weight with water and observed visually after 1 hour, even if it appears cloudy, if no suspended solids, precipitates, or other deposits are observed, the surface tension can be measured.

[0012] The surfactant (A) is not particularly limited as long as it has a solubility in 100g of water at 25°C greater than 0.025g and 0.05g or less, and a surface tension of 35mN / m or less at 25°C when diluted to 0.05% by weight with water. Examples of surfactants (A) include polyhydric alcohol fatty acid esters [e.g., sorbitan monolaurate (solubility: 0.03g, surface tension: 33.1mN / m)], sulfosuccinate ester salts having alkyl groups with 10 to 20 carbon atoms [e.g., ditridecyl sulfosuccinate sodium (solubility: 0.03g, surface tension: 29.5mN / m)], and fatty acid alkanolamides [e.g., coconut oil fatty acid diethanolamide (solubility: 0.05g, surface tension: 27.3mN / m)]. Surfactants (A) may be used alone or in combination of two or more types.

[0013] [Surfactant (B)] The water-permeable treatment agent of the present invention may further contain a surfactant (B) that satisfies at least one of the following conditions: its solubility in 100 g of water at 25°C is greater than 0.05 g, and its surface tension, measured at a temperature of 25°C after being diluted to 0.05% by weight with water and elapsed for 1 hour, is greater than 35 mN / m.

[0014] The surfactant (B) satisfies either or both of the following conditions: its solubility in 100g of water at 25°C is greater than 0.05g, and its surface tension at 25°C when diluted to 0.05% by weight with water is greater than 35mN / m. By further including the surfactant (B) in the water permeability treatment agent, the water permeability of bodily fluids can be enhanced.

[0015] The surfactant (B) is not particularly limited as long as it satisfies either or both of the following conditions: its solubility in 100g of water at 25°C is greater than 0.05g, and its surface tension at 25°C when diluted to 0.05% by weight with water is greater than 35mN / m. The surfactant (B) can be selected from nonionic surfactants (B1), sulfonate-type anionic surfactants (B2), phosphate ester-type anionic surfactants (B3), and ether carboxylic acid-type anionic surfactants (B4), and satisfies either or both of the following conditions: its solubility in 100g of water at 25°C is greater than 0.05g, and its surface tension at 25°C when diluted to 0.05% by weight with water is greater than 35mN / m.

[0016] Nonionic surfactants (B1) that can be used as surfactants (B) include alkylene oxide adducts of polyhydric alcohols or oils and fats (B1-1), fatty acid esters of polyhydric alcohols or alkylene oxide adducts of oils and fats (B1-2), fatty acid esters of polyhydric alcohols (B1-3), polyoxyalkylene glycol diesters (B1-4), alkylene oxide adducts of fatty acids (B1-5), alkylene oxide adducts of monohydric higher alcohols (B1-6), etc., that satisfy either or both of the following conditions: solubility in 100g of water at 25°C is greater than 0.05g, and surface tension is greater than 35mN / m.

[0017] From the viewpoint of excellent water permeability, castor oil and hydrogenated castor oil are preferred as oils common to (B1-1) and (B1-2), and glycerin and trimethylolpropane are preferred as polyhydric alcohols common to (B1-1) and (B1-3).

[0018] Alkylene oxide adducts of polyhydric alcohols are obtained by adding alkylene oxide to the above-mentioned polyhydric alcohols, and alkylene oxide adducts of fats and oils are obtained by adding alkylene oxide to the above-mentioned fats and oils. Examples of alkylene oxides include those having 2 to 4 carbon atoms, and examples include those obtained by block polymerization or random polymerization of ethylene oxide (EO) and propylene oxide (PO).

[0019] Specific examples of (B1-1) include castor oil EO 25 molar adduct (solubility in 100g of water at 25°C: 10g or more), castor oil EO 10 molar adduct (surface tension at 25°C when diluted to 0.05% by weight with water: 41.0 mN / m), trimethylolpropane PO 6 mol EO 10 molar adduct (surface tension at 25°C when diluted to 0.05% by weight with water: 36.2 mN / m), and glycerin PO 90 molar EO 20 molar adduct (surface tension at 25°C when diluted to 0.05% by weight with water: 35.7 mN / m).

[0020] The fatty acid ester (B1-2) of the alkylene oxide adduct of polyhydric alcohol or oil is the esterification reaction product of (B1-1) and a fatty acid. The ester may be a monoester, a diester, or the like. Examples of fatty acids used as raw materials include aliphatic carboxylic acids with 8 to 24 carbon atoms [aliphatic saturated carboxylic acids (caprylic acid, 2-ethylhexanoic acid, pelargonic acid, capric acid, lauric acid, tridecanoic acid, isotridecanoic acid, myristic acid, palmitic acid, stearic acid, and isostearic acid, etc.), and aliphatic unsaturated carboxylic acids (oleic acid, linoleic acid, linolenic acid, ricinoleic acid, and rapeseed oil fatty acids, etc.)].

[0021] Specific examples of (B1-2) include dioleic acid ester of castor oil EO 25-mol adduct (surface tension at 25 °C when diluted to 0.05 wt% with water: 51.3 mN / m), trioleic acid ester of hydrogenated castor oil EO 20-mol (surface tension at 25 °C when diluted to 0.05 wt% with water: 57.4 mN / m), and polyester of EO 25-mol adduct of hydrogenated castor oil, maleic acid, and stearic acid (number average molecular weight: 6000) (surface tension at 25 °C when diluted to 0.05 wt% with water: 43.1 mN / m), etc.

[0022] The fatty acid ester of polyhydric alcohol (B1-3) is an esterification reaction product of the above polyhydric alcohol and fatty acid. Examples of the raw material fatty acid include the fatty acids exemplified in the description of (B1-2). The ester may be a partial ester or a full ester. Specific examples of (B1-3) include partial rapeseed oil fatty acid ester of glycerin (surface tension at 25 °C when diluted to 0.05 wt% with water: 37.3 mN / m) and sorbitan monooleate (surface tension at 25 °C when diluted to 0.05 wt% with water: 39.3 mN / m), etc. As (B1-3), commercially available products may be used. Examples of such commercially available products include sorbitan monooleate [Sanyo Chemical Industries, Ltd., "Ionet S-80", surface tension at 25 °C when diluted to 0.05 wt% with water: 39.3 mN / m], etc.

[0023] The polyoxyalkylene glycol diester (B1-4) is a diester of polyoxyalkylene glycol and fatty acid. Examples of the alkylene oxide include alkylene oxides having 2 to 4 carbon atoms, and those obtained by block polymerization or random polymerization of ethylene oxide (EO) and propylene oxide (PO). Among these, EO is preferred. Examples of the raw material fatty acid include the fatty acids exemplified in the description of (B1-2).

[0024] Specific examples of (B1-4) include polyoxyethylene glycol (number average molecular weight; 400) diolate (surface tension at 25°C when diluted to 0.05% by weight with water: 55.1 mN / m).

[0025] Examples of alkylene oxide adducts of fatty acids (B1-5) include alkylene oxide adducts of aliphatic monocarboxylic acids having 8 to 30 carbon atoms. Examples of alkylene oxides include those exemplified in the explanation of (B1-4).

[0026] Specific examples of (B1-5) include polyoxyethylene glycol (number average molecular weight; 400) monooleate (surface tension at 25°C when diluted to 0.05% by weight with water: 39.2 mN / m).

[0027] Alkylene oxide adducts of monohydric higher alcohols (B1-6) include alkylene oxide adducts of aliphatic monohydric alcohols having 8 to 30 carbon atoms. Examples of alkylene oxides include those exemplified in the explanation in (B1-4).

[0028] A specific example of (B1-6) is the EO20 molar adduct of lauryl alcohol (solubility in 100g of water at 25°C: 10g or more).

[0029] The HLB of the nonionic surfactant (B1) used as surfactant (B) is preferably 2 to 12, and more preferably 3 to 11, from the viewpoint of excellent water permeability.

[0030] In this invention, HLB is an index that indicates the balance between hydrophilicity and lipophilicity, and can be calculated from the ratio of the organic value to the inorganic value of an organic compound using the Oda method described on page 212 of "Introduction to Surfactants" (published by Sanyo Chemical Industries, Ltd. in 2007, written by Takehiko Fujimoto). HLB=10×Inorganic / Organic The organic and inorganic values ​​for deriving HLB can be calculated using the values ​​in the table on page 213 of the aforementioned "Introduction to Surfactants."

[0031] When using two or more nonionic surfactants (B1), it is preferable that each has an HLB of 2 to 12.

[0032] As the sulfonate-type anionic surfactant (B2), a dialkyl sulfosuccinate salt having an alkyl group with 6 to 9 carbon atoms is preferred from the viewpoint of water permeability, and dioctyl sulfosuccinate sodium (solubility in 100 g of water at 25°C: 10 g or more) is more preferred. The alkyl group may be linear or branched.

[0033] As for the phosphate ester type anionic surfactant (B3), from the viewpoint of water permeability, potassium phosphate salts of aliphatic alcohols having 8 to 16 carbon atoms, potassium phosphate salts of aliphatic alcohol EO adducts having 8 to 16 carbon atoms (preferably 3 to 5 moles of EO adduct), and potassium phosphate salts of lauryl alcohol EO 3 molar adduct (solubility in 100g of water at 25°C: 10g or more) are preferred.

[0034] As the ether carboxylic acid type anionic surfactant (B4), polyoxyethylene lauryl ether acetate is preferred, for example. A commercially available product may be used as (B4). Examples of commercially available products include polyoxyethylene lauryl ether acetate [Sanyo Chemical Industries, Ltd., "Viewlight LCA-25NH", surface tension at 25°C when diluted to 0.05% by weight with water: 35.2 mN / m].

[0035] The surfactant (B) preferably includes at least one surfactant selected from nonionic surfactants with HLB 2 to 12, sulfonate-type anionic surfactants, phosphate ester-type anionic surfactants, and ether carboxylic acid-type anionic surfactants. Surfactant (B) may be used alone or in combination of two or more types.

[0036] When the water-permeable treatment agent contains surfactant (A) and surfactant (B), the ratio of (A) to the total weight of (A) and (B) is preferably 10% by weight or more, more preferably 15% by weight or more, preferably 70% by weight or less, and more preferably 50% by weight or less.

[0037] The water-permeable treatment agent of the present invention may contain other surfactants in addition to surfactant (A) and surfactant (B).

[0038] Furthermore, the water-permeable treatment agent of the present invention may contain surfactant (A), surfactant (B), and other additives other than surfactants as needed. Examples of additives include solvents (water and organic solvents, preferably water and ethanol), lubricants such as waxes, antioxidants, UV absorbers, defoamers, preservatives, and fragrances. The additive content in the permeable treatment agent of the present invention is preferably 5% by weight or less, and more preferably 0.1 to 1% by weight, based on the weight of the non-volatile component in the permeable treatment agent. In the present invention, the "non-volatile component" is the residue after heating and drying the sample in a glass petri dish without a lid in a circulating air dryer at 130°C for 45 minutes.

[0039] The water-permeable treatment agent of the present invention may be applied to the target fibers in a single application step, or it may be applied to the target fibers in multiple application steps. When the coating is applied in a single application process, the water-permeable treatment agent can be manufactured by blending surfactant (A) and other components added as needed [surfactant (B), other surfactants, and additives, etc.], and mixing them uniformly at room temperature or, if necessary, by heating (e.g., 30-70°C). The order and method of blending each component are not particularly limited.

[0040] When the water-permeable treatment agent of the present invention is applied to the target fibers in multiple application steps, the water-permeable treatment agent, manufactured in the same manner as when applied in a single application step, may be applied in multiple separate steps. Alternatively, multiple types of agents containing some of the components of the water-permeable treatment agent may be prepared and applied in multiple steps. An agent containing some of the components of a water-permeable treatment agent can be manufactured by blending the components contained in the agent and mixing them uniformly at room temperature or, if necessary, by heating (e.g., 30-70°C). The order and method of blending each component are not particularly limited.

[0041] The water-permeable treatment agent of the present invention is preferably used for fibers (preferably hydrophobic fibers). Fibers to which the water-permeable treatment agent of the present invention is attached are preferably used in nonwoven fabric products, and more preferably in the top sheet of absorbent articles such as disposable diapers and sanitary napkins.

[0042] [Water-permeable fiber] The water-permeable fiber of the present invention is formed by attaching the water-permeable treatment agent of the present invention to a hydrophobic fiber. The water-permeable fiber of the present invention is a fiber formed by attaching the water-permeable treatment agent of the present invention to a hydrophobic fiber, and is a fiber to which water permeability has been imparted by attaching the water-permeable treatment agent of the present invention. There are no particular restrictions on the method of applying the water-permeable treatment agent to the hydrophobic fibers; methods such as dip lubrication, oiling roll method, immersion method, and spraying method can be used in any process such as spinning or drawing.

[0043] In the permeable fibers of the present invention, it is sufficient that surfactant (A) and optionally surfactant (B) are attached, and the attached permeable treatment agent itself may be uniform or non-uniform.

[0044] The amount of water-permeable treatment agent applied is preferably such that the weight ratio of the non-volatile component in the water-permeable treatment agent is 0.02 to 2 parts by weight, more preferably 0.05 to 2 parts by weight, and even more preferably 0.1 to 2 parts by weight, per 100 parts by weight of hydrophobic fibers (weight before application of the water-permeable treatment agent).

[0045] Methods for applying a water-permeable treatment agent to hydrophobic fibers include a method (Method 1) in which the water-permeable treatment agent of the present invention is applied in one or more application steps, and a method (Method 2) in which several types of agents containing a part of the components of the water-permeable treatment agent of the present invention are prepared and applied in multiple steps. When applying a water-permeable treatment agent to hydrophobic fibers using Method 1, the water-permeable treatment agent can be applied to the hydrophobic fibers as an aqueous emulsion. After treating the hydrophobic fibers with the water-permeable treatment agent as an aqueous emulsion, it is preferable to remove volatile components by heating. The aqueous emulsion used in Method 1 is preferably prepared by methods such as diluting the permeable treatment agent with water at 20-40°C, or by adding the permeable treatment agent to water at 20-40°C and emulsifying it. The content of the water-permeable treatment agent in the aqueous emulsion can be selected according to the application, but the weight percentage of the non-volatile component in the water-permeable treatment agent is preferably 0.05 to 20% by weight, and more preferably 0.1 to 10% by weight, based on the weight of the aqueous emulsion.

[0046] In Method 1, methods such as dip lubrication, oiling roll method, immersion method, and spraying method can be used to attach the aqueous emulsion to the hydrophobic fibers. After treating the hydrophobic fibers with the aqueous emulsion, it is preferable to remove volatile components by heating.

[0047] In Method 2, when multiple agents containing a portion of the components of the aqueous treatment agent are used, the agent containing a portion of the components of the water-permeable treatment agent can be attached to the hydrophobic fibers as an aqueous emulsion. When the agent containing a portion of the components of the water-permeable treatment agent is used as an aqueous emulsion, it can be manufactured in the same way as the aqueous emulsion described in Method 1. The weight percentage of the non-volatile component in the agent containing a portion of the components of the water-permeable treatment agent is preferably 0.05 to 20% by weight, and more preferably 0.1 to 10% by weight, based on the weight of the aqueous emulsion. The method for attaching the aqueous emulsion to the hydrophobic fibers is the same as the method for attaching the aqueous emulsion to the hydrophobic fibers in Method 1.

[0048] In the second and subsequent adhesion steps, the permeable treatment agent or an agent containing a portion of the components of the permeable treatment agent is applied to the fibers to which the permeable treatment agent or an agent containing a portion of the components of the permeable treatment agent has been applied in the previous adhesion step (or to fibers to which a portion of the permeable treatment agent or an agent containing a portion of the components of the permeable treatment agent has been applied and which have been made into a nonwoven fabric). When the aforementioned nonwoven fabric is used, the nonwoven fabric of the present invention can be obtained directly when the second and subsequent adhesion steps are completed, and the manufacturing process of the nonwoven fabric can be simplified.

[0049] The aforementioned coating method is not particularly limited, but examples include coating the heated second agent using a bar coater and a non-contact coater, spray coating, and dipping.

[0050] In this invention, hydrophobic fiber means a fiber whose water absorption rate is 1% by weight or less at a temperature of 25°C and a relative humidity of 65%. The hydrophobic fibers are not particularly limited, and hydrophobic synthetic fibers can be used, such as fibers made of polyolefins, polyesters, and polyamides. Examples of polyolefins include polyethylene, polypropylene, ethylene vinyl acetate copolymer, ethylene-propylene copolymer, and ethylene-propylene-1-butene copolymer. Examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene terephthalate isophthalate, and polyether polyester. Examples of polyamides include nylon 6,6 and nylon 6.

[0051] The permeable fibers of the present invention are preferably in the form of a fabric, such as woven fabrics, knitted fabrics, and nonwoven fabrics. Alternatively, fibers mixed by methods such as blending cotton, blending, blending fibers, interknitting, and interweaving may be used in the form of a fabric. Among these, nonwoven fabrics are particularly preferred.

[0052] [Non-woven fabric] The nonwoven fabric of the present invention contains the water-permeable fibers of the present invention. The nonwoven fabric using the water-permeable fibers of the present invention is suitably used as a top sheet for absorbent articles, particularly as a top sheet for sanitary materials such as disposable diapers. The nonwoven fabric and water-permeable fibers of the present invention can also be used as a second sheet, absorbent material, industrial or medical wiper, absorbent pad, and water-permeable sheet.

[0053] The nonwoven fabric of the present invention can be manufactured by forming a fiber laminate from short fibers treated with the water-permeable treatment agent of the present invention using a dry or wet method, and then pressing them with a heated roll, fusing them with air heating, or entangling the fibers with a high-pressure water stream. Alternatively, a nonwoven fabric can also be obtained by applying the water-permeable treatment agent of the present invention to a nonwoven fabric composed of hydrophobic fibers obtained by methods such as the spunbond method, meltblown method, and flash spinning method.

[0054] [Absorbent articles] The absorbent article of the present invention includes the nonwoven fabric of the present invention. Examples of the absorbent article of the present invention include disposable diapers and sanitary napkins (sanitary napkins, etc.). In the absorbent article of the present invention, the nonwoven fabric of the present invention is preferably used as a top sheet for sanitary materials such as disposable diapers. It can also be used in second seats, absorbent materials, and absorbent pads. [Examples]

[0055] The present invention will be further described below with reference to examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, % hereafter refers to weight %. 3、 5. 6、7、 Numbers 8, 9, 12, 13, and 14 are examples.

[0056] [Manufacturing Example 1: Manufacturing of Surfactant (A-2)] In a stainless steel autoclave equipped with a thermometer and stirrer, 766.4 parts by weight of a diester of fumaric acid and tridecanol, 80.8 parts by weight of deionized water, and 150.1 parts by weight of sodium disulfite were sequentially charged. After purging with nitrogen under reduced pressure, the temperature was raised and the autoclave was kept at 100°C while stirring. The temperature was then raised to 125°C and the sulfonation reaction was continued. Next, the mixture was cooled to 70°C and 93.0 parts by weight of ethanol was added to the reactants. After that, the mixture was cooled to 40°C and 5.5 parts by weight of a 5% by weight sodium carbonate aqueous solution was added and stirred for 1 hour. Then, 2.6 parts by weight of a 5% by weight hydrogen peroxide solution was added and stirred for 1 hour to obtain (A-2) ditridecyl sulfosuccinate sodium.

[0057] [Manufacturing Example 2: Manufacturing of Surfactant (A-3)] In a reaction vessel equipped with a thermometer, reflux condenser, stirrer, and distillation apparatus, 106.2 parts by weight of diethanolamine and 0.4 parts by weight of sodium hydroxide were charged. After purging the vessel with nitrogen, the pressure was reduced to 20-30 mmHg. The temperature of the reaction system was then raised to 120-130°C and maintained at this temperature for 1 hour. After confirming that the distillation of water had completely stopped, the reaction system was cooled to 60°C, and 214.2 parts by weight of coconut oil fatty acid methyl was added. The reaction system was aged for 1 hour under conditions of 20-30 mmHg and 65-70°C, while distilling off the methanol produced. After aging, 286.2 parts by weight of (A-3) coconut oil fatty acid diethanolamide was obtained.

[0058] [Manufacturing Example 3: Manufacturing of Surfactant (A'-1)] In a reaction vessel equipped with a stirrer and a thermometer, 330 parts by weight of coconut oil alcohol and 101 parts by weight of anhydrous phosphoric acid were charged and reacted at 60°C. After that, 94 parts by weight of potassium hydroxide was added to obtain (A'-1) potassium phosphate salt of coconut oil alcohol.

[0059] [Manufacturing Example 4: Manufacturing of Surfactant (B-2)] In a 1 L autoclave equipped with a stirrer, thermometer, pressure gauge, pressure-resistant dropping funnel, and vacuum and nitrogen introduction lines, 459 parts by weight of castor oil and 0.1 parts by weight of potassium hydroxide were added and stirring was started. Nitrogen was then added and the temperature was raised to 90°C, then the pressure was reduced to 0.005 MPa and the mixture was stirred for 1 hour. Next, the temperature was raised to 130 ± 10°C, and 550 parts by weight of ethylene oxide were added dropwise while maintaining a pressure of 4 to 6.5 kPa. After that, 20 parts by weight of Kyoward 600 (manufactured by Kyowa Chemical) were added and the mixture was treated with adsorption at 95°C for 1 hour, followed by filtration to remove alkali metals. After cooling to 60°C, the mixture was removed to obtain (B-2) Castor Oil EO 25 molar adduct.

[0060] [Manufacturing Example 5: Manufacturing of Surfactant (B-1)] In a reaction vessel equipped with a stirrer and a thermometer, 778 parts by weight of the castor oil EO25 molar adduct prepared in Production Example 4 and 220 parts by weight of oleic acid were charged. 4 parts by weight of p-toluenesulfonic acid was added as a catalyst, and the vessel was purged with nitrogen. The temperature was raised to 150°C and the reaction was carried out to obtain (B-1) dioleic acid ester of the castor oil EO25 molar adduct.

[0061] [Manufacturing Example 6: Manufacturing of Surfactant (B-3)] In an autoclave equipped with a stirrer, thermometer, pressure gauge, pressure-resistant dropping funnel, and vacuum and nitrogen introduction lines, 13.4 parts by weight of trimethylolpropane(I) and 0.8 parts by weight of potassium hydroxide were added and stirring was started. Nitrogen was then added, the temperature was raised to 90°C, the pressure was reduced to 0.005 MPa, and the mixture was stirred for 1 hour. Next, the temperature was raised to 130 ± 10°C, and 406 parts by weight of propylene oxide were added dropwise while maintaining a pressure of 4 to 6.5 kPa. It took 1 hour to complete the dropwise addition and 2 hours for the pressure to drop completely. Next, 88 parts by weight of ethylene oxide were added dropwise. It took 0.5 hours to complete the dropwise addition and 0.5 hours for the pressure to drop completely. After that, 10 parts by weight of Kyoward 600 (manufactured by Kyowa Chemical) was added, and the mixture was treated with adsorption at 95°C for 1 hour, followed by filtration to remove alkali metals. After cooling to 60°C, the mixture was removed to obtain 500 parts by weight of the surfactant (B-3) (trimethylolpropane PO6 8 molars EO10 molars adduct).

[0062] [Manufacturing Example 7: Manufacturing of Surfactant (B-4)] In a reaction vessel equipped with a stirrer and thermometer, 100 parts by weight of rapeseed oil and 10 parts by weight of glycerin were charged, 1 part by weight of potassium carbonate was added as a catalyst, and the vessel was purged with nitrogen. The temperature was raised to 200°C and the reaction was carried out for 1 hour to obtain surfactant (B-4) (a partial ester compound of glycerin and rapeseed oil fatty acid).

[0063] [Manufacturing Example 8: Manufacturing of Surfactant (B-5)] In a stainless steel autoclave equipped with a thermometer and stirrer, 542.6 parts by weight of a diester of fumaric acid and 2-ethylhexanol, 44.3 parts by weight of propylene glycol, 80.8 parts by weight of deionized water, and 150.1 parts by weight of sodium disulfite were sequentially charged, and stirring was started. After purging with nitrogen under reduced pressure, the temperature was raised and maintained at 100°C while stirring was continued. The temperature was then raised to 125°C and the sulfonation reaction was continued. Next, the mixture was cooled to 95°C, and 93.0 parts by weight of propylene glycol was added to the reactants. Then, the mixture was cooled to 40°C, and 4.1 parts by weight of a 5% by weight aqueous solution of sodium carbonate was added and stirred for 1 hour. Furthermore, 2.6 parts by weight of a 5% by weight aqueous solution of hydrogen peroxide was added and stirred for 1 hour to obtain the surfactant (sodium dioctyl sulfosuccinate) of (B-5).

[0064] [Manufacturing Example 9: Manufacturing of Surfactant (B-6)] In Production Example 3, the surfactant (potassium phosphate salt of lauryl alcohol EO3 adduct) was obtained in the same manner as in Production Example 3, except that 563 parts by weight of lauryl alcohol EO3 adduct was used instead of 330 parts by weight of coconut oil alcohol.

[0065] [Manufacturing Example 10: Manufacturing of Surfactant (B-7)] In an autoclave equipped with a stirrer, thermometer, pressure gauge, pressure-resistant dropping funnel, and vacuum and nitrogen introduction lines, 9.2 parts by weight of trimethylolpropane and 0.8 parts by weight of potassium hydroxide were added and stirring was started. Nitrogen was then added, the temperature was raised to 90°C, the pressure was reduced to 0.005 MPa, and the mixture was stirred for 1 hour. Next, the temperature was raised to 130 ± 10°C, and 522 parts by weight of propylene oxide was added dropwise while maintaining a pressure of 4 to 6.5 kPa. It took 1 hour to complete the dropwise addition and 2 hours for the pressure to drop completely. Next, 88 parts by weight of ethylene oxide was added dropwise. It took 0.5 hours to complete the dropwise addition and 0.5 hours for the pressure to drop completely. After that, 10 parts by weight of Kyoward 600 (manufactured by Kyowa Chemical) was added, and the mixture was treated with adsorption at 95°C for 1 hour, followed by filtration to remove alkali metals. After cooling to 60°C, the mixture was removed to obtain 500 parts by weight of the surfactant (B-7) (glycerin PO90 molars EO20 molars adduct).

[0066] [Manufacturing Example 11: Manufacturing of Surfactant (B-9)] In a 1 L autoclave equipped with a stirrer, thermometer, pressure gauge, pressure-resistant dropping funnel, and vacuum and nitrogen introduction lines, 459 parts by weight of castor oil and 0.1 parts by weight of potassium hydroxide were added and stirring was started. Nitrogen was then added, the temperature was raised to 90°C, the pressure was reduced to 0.005 MPa, and the mixture was stirred for 1 hour. Next, the temperature was raised to 130 ± 10°C, and 220 parts by weight of ethylene oxide were added dropwise while maintaining a pressure of 4 to 6.5 kPa. After that, 20 parts by weight of Kyoward 600 (manufactured by Kyowa Chemical) were added, and the mixture was treated with adsorption at 95°C for 1 hour, followed by filtration to remove alkali metals. After cooling to 60°C, the mixture was removed to obtain (B-9) Castor Oil EO 10 molar adduct.

[0067] <Explanation of each ingredient> The raw materials corresponding to each component used in the examples and comparative examples are as follows: (A-1): Sorbitan monolaurate [Product name: Ionet S-20, manufactured by Sanyo Chemical Industries, Ltd.] (A-2): Ditridecyl sulfosuccinate sodium prepared in Production Example 1 (A-3): Coconut oil fatty acid diethanolamide produced in Production Example 2 (A'-1): Potassium phosphate salt of coconut oil alcohol produced in Production Example 3 (A'-2): Potassium phosphate salt of octyl alcohol EO2 molar adduct [Product name: Safanol BW, manufactured by Sanyo Chemical Industries, Ltd.] (A'-3): Polyoxyethylene-modified dimethyl silicone [Product name: KF-6015, manufactured by Shin-Etsu Chemical Co., Ltd.] (A'-4): Tri(caprylic / capric acid)glyceryl (product name: ODO, manufactured by Nisshin Oillio Group Ltd.) (B-1): Dioleate ester of castor oil EO25 molar adduct produced in Production Example 5 (HLB: 8.7) (B-2): Castor oil EO 25 molar adduct produced in Production Example 4 (HLB: 11.6) (B-3): Trimethylolpropane PO6 8 molars EO10 molars adduct prepared in manufacturing example 6 (HLB: 6.2) (B-4): Partial ester compound of glycerin and rapeseed oil fatty acid produced in Production Example 7 (HLB: 2.9) (B-5): Sodium dioctyl sulfosuccinate prepared in Production Example 8 (B-6): Potassium phosphate salt of the 3-mol EO adduct of lauryl alcohol prepared in Production Example 9 (B-7): Glycerin PO90 molars EO20 molars adduct prepared in manufacturing example 10 (HLB: 6.7) (B-8): Sorbitan monooleate [Product name: Ionet S-80, manufactured by Sanyo Chemical Industries, Ltd.] (HLB: 8.7) (B-9): Castor oil EO 10 molar adduct produced in Production Example 11 (HLB: 8.2) (B-10): Polyoxyethylene lauryl ether acetate [Product name: Viewlight LCA-25NH, manufactured by Sanyo Chemical Industries, Ltd.] (HLB: 9.9)

[0068] <Method for measuring physical properties> The physical properties of each component used in the examples and comparative examples were measured by the following method. The results are shown in Table 1. Components that could not be measured are indicated as "unmeasurable" in Table 1. [Solubility] Under conditions of 25°C and 40% RH humidity, 0.005g of the substance to be measured was added to 100g of deionized water while stirring with a stirrer. The amount of dissolved substance at which it stopped dissolving [at least one of the following was observed: suspension, precipitation, sedimentation, or turbidity (transmittance of 95 or less)] was defined as the solubility. For substances that were judged to have stopped dissolving after adding 0.005g, the solubility was set to "less than 0.005". The maximum amount of substance to be added was 10g, and for substances that were judged to have dissolved after adding 10g, the solubility was set to "10 or more".

[0069] [surface tension] After diluting the sample to be measured with water to 0.05% by weight and allowing it to stand for 1 hour, the surface tension was measured using the plate method (Wilhelmy method) with an automatic surface tensimeter (manufactured by Kyowa Interface Science Co., Ltd.) under conditions of 25°C and 40% RH. If at least one of the following was observed visually in the sample solution after diluting the sample with water and allowing it to stand for 1 hour, the sample solution was judged to be heterogeneous, and the surface tension could not be measured.

[0070] <Examples 1-14, Comparative Examples 1-4> [Example 1] (1) Manufacturing of water permeability treatment agents A water permeability treatment agent was prepared by stirring 30 parts of surfactant (A-2), 25 parts of surfactant (B-1), 20 parts of surfactant (B-3), 15 parts of surfactant (B-4), 10 parts of surfactant (B-5), and 10 parts of water at 25°C for 30 minutes.

[0071] (2) Manufacturing of nonwoven fabrics Each of the obtained water-permeable treatment agents was diluted with water at 25°C to obtain a diluted water-permeable treatment agent solution, resulting in a non-volatile component content of 1.0% by weight. 150g of the diluted water-permeable treatment agent solution was applied to 300g of fiber material using the dip application method. The amount of non-volatile component of the water-permeable treatment agent attached to the fiber [weight ratio (weight%) to the weight of the fiber material] was 0.5% by weight. The fiber material used was a polyester (core)-polyethylene (sheath) composite fiber without any fiber treatment agents attached, with a single fiber fineness of 2.2 Dtex and a fiber length of 51mm. Fibers treated with a water-permeable treatment agent were placed in an 80°C hot air dryer for 1 hour, and then left to dry at room temperature for more than 4 hours to obtain fibers to which the water-permeable treatment agent had adhered. The obtained fibers were passed through a roller card to produce a card web with a basis weight of 25 g / m2. The obtained card web was subjected to hot air treatment at 140°C for 10 seconds to obtain an air-through nonwoven fabric (thickness of 3 mm). The water permeability, repeated water permeability (water permeability when repeatedly absorbing bodily fluids), and dryness of the obtained nonwoven fabric were evaluated. The results are shown in Table 1.

[0072] [Examples 2-14, Comparative Examples 1-4] A water-permeable treatment agent was prepared by performing the same procedure as in Example 1, except that the type and amount of surfactant used were replaced with those listed in Table 1. A nonwoven fabric was produced using this water-permeable treatment agent. The water permeability and dryness of the obtained nonwoven fabric were repeatedly evaluated. The results are shown in Table 1. In Table 1, (A) indicates surfactant (A), (A') indicates the surfactant used in place of surfactant (A), and (B) indicates surfactant (B).

[0073] <Evaluation Test> [Evaluation of water permeability and repeated water permeability (durable water permeability)] From each of the nonwoven fabrics produced in the examples and comparative examples, rectangular pieces of nonwoven fabric measuring 10 cm x 10 cm were cut out and subjected to a water permeability test. (1) First permeability test Under conditions of 25°C and 65% RH humidity, each example of nonwoven fabric was placed on top of filter paper (Toyo Filter Paper Co., Ltd., No. 5), and one drop (approximately 0.05 mL) of physiological saline solution was dropped from a burette placed 10 mm above the surface of the nonwoven fabric. The time it took for the water droplet to disappear from the surface of the nonwoven fabric was measured. Ten dots were marked on the surface of the nonwoven fabric with a marking pen, and the number of points where the physiological saline solution disappeared in less than 5 seconds was counted. A higher number of points where the disappearance time was less than 5 seconds indicates superior water permeability.

[0074] (2) Permeability tests from the second to the fourth time (i) After the first water permeability test, the nonwoven fabric was placed on top of a commercially available disposable diaper, and a stainless steel ring (6 cm inner diameter, 6 cm height) was placed on top of it. 50 mL of saline solution was passed through the ring (into the inner diameter of the ring) and absorbed by the disposable diaper. After removing the nonwoven fabric from the disposable diaper and drying it, one drop of saline solution was again dropped onto 10 marked locations on the surface of the nonwoven fabric, and the disappearance time was measured for each of the 10 locations. The number of locations where the disappearance time was less than 5 seconds was counted. (ii) A third permeability test was conducted on the nonwoven fabric after the second permeability test by performing the same procedure as in (i) above. Furthermore, a fourth permeability test was conducted on the nonwoven fabric after the third permeability test by performing the same procedure as in (i) above. A higher number of areas where the water disappears in less than 5 seconds after repeated use indicates superior repeated water permeability. The evaluation results for durable water permeability in Table 1 show the number of areas where the water disappears in less than 5 seconds.

[0075] [Evaluation of dryness] From each of the nonwoven fabrics produced in the examples and comparative examples, rectangular pieces of nonwoven fabric measuring 10 cm x 10 cm were cut out and subjected to a dryness evaluation test. (1) Measurement of water retention rate after the first pass of liquid through Under conditions of 25°C and 65% RH humidity, a rectangular nonwoven fabric (10cm x 10cm) whose weight (W0) had been measured in advance was placed on top of three layers of filter paper (Toyo Filter Paper Co., Ltd., No. 424). A stainless steel ring (6cm inner diameter, 6cm height) was then placed on top of the nonwoven fabric, and 30mL of artificial urine was passed through it (into the inner diameter of the ring). After 3 minutes, the nonwoven fabric for each case was removed from the filter paper, and the weight (W1) of the nonwoven fabric after the liquid had passed through was measured. Using the measured values, the water retention rate after the first pass was calculated using the following formula. Water retention rate after the first liquid pass = 100 × {(Weight of nonwoven fabric after liquid pass W1) - (Weight of nonwoven fabric before liquid pass W0)} / (Weight of nonwoven fabric before liquid pass W0) A lower water retention rate indicates a better reduction in residual liquid (i.e., superior drying performance). The water retention rate (%) is listed in the evaluation results for drying performance in Table 1.

[0076] (2) Measurement of water retention rate after the second and third passes of liquid. (i) After measuring the water retention rate following the first pass of liquid through the nonwoven fabric, it was placed on top of three layers of filter paper (Toyo Filter Paper Co., Ltd., No. 424), and a stainless steel ring (6 cm inner diameter, 6 cm height) was placed on top of that. 30 mL of artificial urine was then passed through the ring (into the inner diameter of the ring). After 3 minutes, the nonwoven fabric was removed from the filter paper, and the weight of the nonwoven fabric after liquid passage (W2) was measured. Using the measured values, the water retention rate after the second pass of liquid was calculated using the following formula. Water retention rate after the second liquid pass = 100 × {(Weight of nonwoven fabric after liquid pass W2) - (Weight of nonwoven fabric before liquid pass W0)} / (Weight of nonwoven fabric before liquid pass W0) (ii) After measuring the weight of the nonwoven fabric after the second pass of liquid, the same procedure as in (i) above was performed to measure the weight of the nonwoven fabric (W3) after the third pass of liquid. Using the measured values, the water retention rate after the third pass of liquid was calculated using the following formula. Water retention rate after the third pass of liquid = 100 × {(Weight of nonwoven fabric after liquid pass of liquid W3) - (Weight of nonwoven fabric before liquid pass of liquid W0)} / (Weight of nonwoven fabric before liquid pass of liquid W0)

[0077] [Table 1]

[0078] As shown in Table 1, the nonwoven fabrics coated with the water-permeable treatment agents of Examples 1 to 14, which contain surfactant (A), showed low water retention rates and excellent reduction in residual liquid. From these results, it was found that the present invention can provide a water-permeable treatment agent, water-permeable fibers, nonwoven fabrics, and absorbent articles that can reduce the amount of residual liquid on the surface material.

Claims

1. A surfactant (A) whose solubility in 100g of water at 25°C is greater than 0.025g and 0.05g or less, and whose surface tension measured at 25°C after dilution to 0.05% by weight with water and after 1 hour is 35 mN / m or less, A water permeability treatment agent containing a surfactant (B) (excluding phosphate ester salt type anionic surfactants) that satisfies at least one of the following conditions: its solubility in 100 g of water at 25°C is greater than 0.05 g, and its surface tension measured at 25°C after dilution to 0.05 wt% with water and elapsed for 1 hour is greater than 35 mN / m. The surfactant (B) comprises at least one surfactant selected from nonionic surfactants with an HLB of 2 to 12, sulfonate-type anionic surfactants, and ether carboxylic acid-type anionic surfactants. The nonionic surfactants of HLB 2 to 12 are at least one surfactant selected from the following: alkylene oxide adducts of polyhydric alcohols or fats and oils (B1-1), fatty acid esters of polyhydric alcohols or fats and oils (B1-2), fatty acid esters of polyhydric alcohols (B1-3), polyoxyalkylene glycol diesters (B1-4), alkylene oxide adducts of fatty acids (B1-5), and alkylene oxide adducts of monohydric higher alcohols (B1-6). The ratio of surfactant (A) to the total weight of surfactant (A) and surfactant (B) is 15 to 70% by weight. A water-permeable treatment agent wherein the surfactant (B) contains a fatty acid ester (B1-2) of an alkylene oxide adduct of a polyhydric alcohol or oil, the polyhydric alcohol is glycerin and / or trimethylolpropane, and the oil is castor oil and / or hydrogenated castor oil.

2. The water-permeable treatment agent according to claim 1, wherein the ratio of surfactant (A) to the total weight of surfactant (A) and surfactant (B) is 15 to 50% by weight.

3. A permeable fiber comprising a hydrophobic fiber to which the permeable treatment agent described in claim 1 or 2 is attached, wherein the proportion of the non-volatile component of the permeable treatment agent is 0.02 to 2 parts by weight per 100 parts by weight of the hydrophobic fiber.

4. A nonwoven fabric containing water-permeable fibers as described in claim 3.

5. An absorbent article comprising the nonwoven fabric described in claim 4.

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