Treatment agent for long-fiber nonwoven fabric and use thereof

Abstract

Provided is a highly hydrophilic treatment agent for a long-fiber nonwoven fabric.　The treatment agent for a long-fiber nonwoven fabric contains a sorbitan fatty acid ester (A) and at least one selected from among a phosphate ester-type anionic surfactant (B) and a nonionic surfactant (C) having a polyoxyalkylene group, and satisfies Condition 1. Condition 1: The foaming power at an effective concentration of 1.0 wt% at 25°C according to the Ross-Miles test method is 150 MM or less immediately after flowing down, and 130 MM or less 5 minutes immediately after flowing down.

Description

Treatment agent for long fiber nonwoven fabric and its use

[0001] The present invention relates to a treatment agent for long-fiber nonwoven fabrics and its use.

[0002] Polyolefin-based synthetic fibers are generally used as raw fibers for nonwoven fabrics. For example, nonwoven fabrics are manufactured using long fibers made of polyolefin-based synthetic fibers. Nonwoven fabrics manufactured using long fibers are called long-fiber nonwoven fabrics. By applying a treatment agent that functions as a nonwoven fabric treatment agent to the nonwoven fabric, functions such as durable hydrophilicity are imparted to the nonwoven fabric. Nonwoven fabrics imparted with functions such as durable hydrophilicity are used in a wide range of fields, including hygiene materials, medical care, and civil engineering.

[0003] Patent Document 1 discloses a treatment agent for nonwoven fabrics containing an ether ester compound.

[0004] International Publication No. 2022 / 065261

[0005] However, the nonwoven fabric treating agent disclosed in Patent Document 1 sometimes lacks hydrophilicity. The present invention was made in view of this situation, and its object is to provide a treating agent for long-fiber nonwoven fabrics that has excellent hydrophilicity. It is also an object of the present invention to provide a long-fiber nonwoven fabric to which this treating agent for long-fiber nonwoven fabrics is attached.

[0006] As a result of extensive research aimed at solving the above-mentioned problems, the present inventors have found that a treatment agent for long-fiber nonwoven fabrics containing specific components and having a foaming power within a certain range can solve the problems. Specifically, the treatment agent for long-fiber nonwoven fabrics of the present invention is a treatment agent for long-fiber nonwoven fabrics containing a sorbitan fatty acid ester (A) and at least one selected from a phosphate ester-type anionic surfactant (B) and a nonionic surfactant (C) having a polyoxyalkylene group, and satisfies the following condition 1. Condition 1: The foaming power at an effective concentration of 1.0% by weight at 25°C, as measured by the Ross-Miles test method, is 150 MM or less immediately after flowing and 130 MM or less 5 minutes after flowing.

[0007] It is preferable that the alkyl group of the activator (B) has 6 to 12 carbon atoms, and the activator (C) has an alkyl group having 6 to 14 carbon atoms. It is preferable that the sorbitan fatty acid ester (A) accounts for 60 to 95% by weight of the nonvolatile content of the treatment agent for long-fiber nonwoven fabrics, and that the total proportion of at least one surfactant selected from the phosphate ester-type anionic surfactant (B) and the nonionic surfactant (C) having a polyoxyalkylene group is 5 to 35% by weight. It is preferable that the felt settling test time below is less than 30 seconds. Felt settling test time: The time it takes for a 2 cm x 2 cm piece of Orifelt S20 (No. 103) manufactured by Nikke Co., Ltd. to settle after being floated in 100 ml of a diluted solution with an effective concentration of 1.0 wt % at 23°C. It is preferable that the sorbitan fatty acid ester is a sorbitan mono-fatty acid ester.

[0008] The long-fiber nonwoven fabric of the present invention is obtained by applying the above-mentioned treatment agent for long-fiber nonwoven fabrics to a long-fiber nonwoven fabric.

[0009] The treatment agent for long-fiber nonwoven fabrics of the present invention provides long-fiber nonwoven fabrics with excellent hydrophilicity. The long-fiber nonwoven fabrics of the present invention have excellent hydrophilicity.

[0010] The treatment agent for long-fiber nonwoven fabrics of the present invention contains a sorbitan fatty acid ester (A), a phosphate ester-type anionic surfactant (B), and at least one surfactant selected from the group consisting of a nonionic surfactant having a polyoxyalkylene group (C). Each component is described in detail below.

[0011] [Sorbitan Fatty Acid Ester (A)] The sorbitan fatty acid ester (A) is an essential component contained in the treatment agent for long-fiber nonwoven fabrics, and is a component that is primarily excellent in hydrophilicity and anti-foaming properties.

[0012] From the viewpoint of anti-foaming properties, the sorbitan fatty acid ester (A) is preferably a compound to which no polyoxyalkylene group is added. From the viewpoint of excellent hydrophilicity, the HLB of the sorbitan fatty acid ester (A) is preferably 6 to 13, more preferably 7 to 12, and most preferably 8 to 11. Examples of the sorbitan fatty acid ester (A) include sorbitan mono-fatty acid esters, sorbitan di-fatty acid esters, and sorbitan tri-fatty acid esters. From the viewpoint of hydrophilicity and anti-foaming properties, it is preferable to include a sorbitan mono-fatty acid ester. The HLB value of the sorbitan fatty acid ester (A) is an index showing 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 by the Oda method described, for example, on page 212 of "Introduction to Surfactants" (published by Sanyo Chemical Industries, Ltd. in 2007, written by Takehiko Fujimoto). HLB = 10 x 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."

[0013] When two or more compounds are used as the sorbitan fatty acid ester (A), the HLB value of the sorbitan fatty acid ester (A) can be calculated by a weighted average. For example, when M1 parts by weight of a compound (AX) having an HLB value of H1 and M2 parts by weight of a compound (AY) having an HLB value of H2 are used in combination as the sorbitan fatty acid ester (A), the HLB value of the sorbitan fatty acid ester (A) can be calculated by the following formula: HLB value of sorbitan fatty acid ester (A) = (H1 x M1 + H2 x M2) / (M1 + M2)

[0014] From the viewpoints of hydrophilicity and anti-foaming properties, the fatty acid constituting the sorbitan fatty acid ester (A) is preferably capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, etc., with lauric acid being particularly preferred. Examples of the sorbitan fatty acid ester (A) include sorbitan monocaprate, sorbitan monolaurate, sorbitan monomyristylates, sorbitan monopalmitate, and sorbitan monooleate, with sorbitan monolaurate being particularly preferred from the viewpoints of hydrophilicity and anti-foaming properties. These sorbitan fatty acid esters may be composed of one or more types. From the viewpoints of hydrophilicity and anti-foaming properties, the sorbitan fatty acid ester (A) is preferably liquid at room temperature (23°C).

[0015] [Phosphate Ester-Type Anionic Surfactant (B)] The phosphate ester-type anionic surfactant (B) is a component that exhibits excellent hydrophilicity when used in combination with the sorbitan fatty acid ester (A) described above.

[0016] From the viewpoint of hydrophilicity, the phosphate ester-type anionic surfactant (B) preferably has an alkyl group having 6 to 12 carbon atoms, more preferably 6 to 10 carbon atoms, and even more preferably 6 to 8 carbon atoms.

[0017] Examples of the phosphate ester-type anionic surfactant (B) include alkyl phosphates such as sodium hexyl phosphate, potassium hexyl phosphate, sodium octyl phosphate, potassium octyl phosphate, sodium 2-ethylhexyl phosphate, potassium 2-ethylhexyl phosphate, sodium dodecyl phosphate, potassium dodecyl phosphate, sodium stearyl phosphate, and potassium stearyl phosphate; polyoxyethylene alkyl ether phosphate salts such as polyoxyethylene (3) lauryl ether sodium phosphate and polyoxyethylene (3) lauryl ether potassium phosphate; and polyoxyethylene alkyl phenyl ether phosphate salts such as polyoxyethylene (3) lauryl phenyl ether sodium phosphate and polyoxyethylene (3) lauryl phenyl ether potassium phosphate. As the phosphate ester-type anionic surfactant (B), alkyl phosphate salts and polyoxyethylene alkyl ether phosphate salts are preferred, with alkyl phosphate salts being more preferred. These phosphate ester-type anionic surfactants (B) may be used alone or in combination of two or more. From the viewpoint of hydrophilicity and anti-foaming properties, the number of moles of polyoxyalkylene added to the phosphate ester-based anionic surfactant (B) is preferably 0 to 5 moles, more preferably 0 to 3 moles, even more preferably 0 to 2 moles, and most preferably 0 mole.

[0018] [Nonionic surfactant (C) having a polyoxyalkylene group] The nonionic surfactant (C) having a polyoxyalkylene group is a component that exhibits excellent hydrophilicity when used in combination with the sorbitan fatty acid ester (A). Examples of the nonionic surfactant (C) having a polyoxyalkylene group include a polyoxyalkylene adduct of an aliphatic alcohol (C-1), a mono- or diester of a polyoxyalkylene glycol and a fatty acid (C-2), and a polyoxyalkylene-modified silicone (C-3).

[0019] From the viewpoint of hydrophilicity and foam-suppressing properties, the nonionic surfactant (C) having a polyoxyalkylene group preferably has an alkyl group having 6 to 14 carbon atoms. These nonionic surfactants having a polyoxyalkylene group may be used alone or in combination of two or more.

[0020] The polyoxyalkylene adduct of aliphatic alcohol (C-1) is a compound having a structure in which an oxyalkylene is added to an aliphatic alcohol. Examples of aliphatic alcohols include 2-ethylhexanol, lauryl alcohol, palmityl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, and behenyl alcohol. In the polyoxyalkylene adduct of aliphatic alcohol, the alkylene oxide preferably has 2 to 4 carbon atoms. When two or more types of alkylene oxides are added, the order of addition is not particularly limited, and the addition form may be either block or random. Furthermore, from the viewpoints of hydrophilicity and foam-suppressing properties, the number of moles of alkylene oxide added is preferably 1 to 150, more preferably 2 to 50, and particularly preferably 3 to 20. From the viewpoints of hydrophilicity and foam-suppressing properties, the number of carbon atoms of the aliphatic alcohol is preferably 1 to 22, more preferably 6 to 14, and even more preferably 12 to 14. It is also preferable that the aliphatic alcohol has a distribution, and it is preferable that the aliphatic alcohol contains at least two kinds of aliphatic alcohols each having a carbon number of 12 to 14. The aliphatic alcohol may be saturated or unsaturated, and may be linear or branched.

[0021] Specific examples of the polyoxyalkylene adduct (C-1) of aliphatic alcohol include polyoxyethylene (6 mol) polyoxypropylene (2 mol) alkyl (C12,13) ​​ether (random adduct), polyoxyethylene (9 mol) polyoxypropylene (13 mol) octyl ether (block adduct), polyoxyethylene (10 mol) polyoxypropylene (2 mol) alkyl (C12,14) ether (random adduct), polyoxyethylene (7 mol) polyoxypropylene (17 mol) alkyl (C12,14) ether (block adduct), polyoxyethylene (12 mol) polyoxypropylene (3 mol) alkyl (C12,13) ​​ether (block adduct), and polyoxyethylene (60 mol) polyoxypropylene (15 mol) octyl ether (block adduct).

[0022] The mono- or diester (C-2) of polyoxyalkylene glycol and fatty acid is an ester compound having a structure in which the polyoxyalkylene glycol and the fatty acid are ester-bonded. Specific examples of the oxyalkylene group constituting the mono- or diester (C-2) of polyoxyalkylene glycol and fatty acid include oxyalkylene groups having 2 to 4 carbon atoms (oxyethylene group, 1,2- or 1,3-oxypropylene group, 1,2-, 1,3-, 1,4-, or 2,3-oxybutylene group, etc.). The oxyalkylene group may be one type or two or more types in combination. When two or more types of oxyalkylene groups are used in combination, they may be added in block or random addition. Specific examples of the fatty acid constituting the mono- or diester (C-2) of polyoxyalkylene glycol and fatty acid include aliphatic carboxylic acids having 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, isostearic acid, etc.), aliphatic unsaturated carboxylic acids (oleic acid, linoleic acid, linolenic acid, etc.), and fatty acids of animal and vegetable oils (coconut oil, palm oil, castor oil, hydrogenated castor oil, beef tallow, hydrogenated beef tallow, lard, etc.)].

[0023] Examples of the mono- or diester (C-2) of polyoxyalkylene glycol and fatty acid include (mono- or di-)esters of polyoxyalkylene glycol and aliphatic carboxylic acids having 8 to 24 carbon atoms. Among these, coconut fatty acid monoesters of polyoxyethylene glycol (having 5 to 10 repeating oxyethylene groups) are preferred from the viewpoint of exerting the effects of the present invention.

[0024] Examples of the polyoxyalkylene-modified silicone (C-3) include copolymers of alkyl (carbon number 1 to 3) siloxane and polyoxyalkylene (preferably the alkylene group has 2 to 5 carbon atoms). Of these, copolymers of dimethylsiloxane and polyoxyalkylene (such as polyoxyethylene, polyoxypropylene, and random or block copolymers of polyoxyethylene and polyoxypropylene) are preferred. Examples of such copolymers include compounds represented by the following general formula (I) or (II):

[0025] (In the formula, M, N, a, and b are average degrees of polymerization, and R represents hydrogen, an alkyl group, or an acetyl group.)

[0026] Here, M is 10 to 10,000, preferably 100 to 300, N is 1 to 1,000, preferably 1 to 100, and it is preferable that M>N, a is 2 to 100, preferably 2 to 50, and b is 0 to 50, preferably 0 to 10. R is preferably hydrogen, an alkyl group having 1 to 4 carbon atoms, or an acetyl group.

[0027]

[0028] (In the formula, A, B, h, and i are the average degree of polymerization, R represents an alkyl group, and R' represents hydrogen, an alkyl group, or an acetyl group.) Here, A is preferably 5 to 10,000, B is preferably 2 to 10,000, h is preferably 2 to 100, and i is preferably 0 to 50. R is preferably an alkyl group having 1 to 5 carbon atoms. R' is preferably hydrogen, an alkyl group having 1 to 4 carbon atoms, or an acetyl group.

[0029] Specific examples of polyoxyalkylene-modified silicone (C-3) include FZ-2104, FZ-2123, FZ-2191, L-7002, L-7604, SF8410, SH3746, SH8400, and SH8700 from the DOWSIL (registered trademark) series manufactured by Dow-Toray Industries, Inc.; KF-351A, KF-352A, KF-353, KF-354L, KF-355, KF-6008, KF-615A, KF-6011, and KF-6012 manufactured by Shin-Etsu Chemical Co., Ltd.; and TSF4440, TSF4441, TSF4445, TSF4446, TSF4450, and TSF4452 manufactured by Momentive Performance Materials Japan, LLC. The HLB of the polyoxyalkylene-modified silicone (C-3) is preferably 4 to 18, more preferably 6 to 16, from the viewpoint of exerting the effects of the present invention.

[0030] [Treatment Agent for Long-Fiber Nonwoven Fabrics] From the viewpoint of hydrophilicity, the treatment agent for long-fiber nonwoven fabrics of the present invention satisfies Condition 1: the foaming power at an effective concentration of 1.0 wt % at 25°C, as measured by the Ross Miles test, is 150 mm or less immediately after flowing down and 130 mm or less 5 minutes after flowing down. In terms of hydrophilicity, Condition 1 is more preferable when the foaming power immediately after flowing down is 140 mm or less, 100 mm or less, 60 mm or less, 50 mm or less, 20 mm or less, 15 mm or less, 10 mm or less, and 0 mm. In terms of hydrophilicity, Condition 1 is more preferable when the foaming power immediately after flowing down is 120 mm or less, 100 mm or less, 60 mm or less, 40 mm or less, 20 mm or less, 10 mm or less, and 0 mm 5 minutes after flowing down.

[0031] From the viewpoint of hydrophilicity, the treating agent for long-fiber nonwoven fabrics of the present invention is preferably one that exhibits a felt settling test time of less than 30 seconds, less than 20 seconds, less than 15 seconds, and less than 10 seconds, in that order. The felt settling test time is the time it takes for a piece of Olieft S20 (No. 103) manufactured by Nikke Co., Ltd., cut into a 2 cm x 2 cm piece, to separate from the liquid surface and begin to settle when floated in 100 ml of an emulsion at 23°C that has been diluted to an effective concentration of 1.0 wt %.

[0032] The proportion of the sorbitan fatty acid ester (A) in the nonvolatile content of the treatment agent for long-fiber nonwoven fabrics of the present invention is preferably 60 to 95% by weight, more preferably 65 to 93% by weight, and even more preferably 70 to 90% by weight, from the viewpoint of hydrophilicity. The nonvolatile content in the present invention refers to the bone-dry component when the treatment agent for long-fiber nonwoven fabrics has reached a constant weight after heat treatment at 105°C to remove the solvent and the like. The effective concentration in the present invention refers to the nonvolatile content.

[0033] When the treating agent for long-fiber nonwoven fabrics of the present invention contains a phosphate ester-type anionic surfactant (B), the proportion of the phosphate ester-type anionic surfactant (B) in the nonvolatile content of the treating agent is preferably 5 to 35% by weight, more preferably 7 to 30% by weight, and even more preferably 10 to 25% by weight, from the viewpoints of hydrophilicity and foam-suppressing properties. When the treating agent for long-fiber nonwoven fabrics of the present invention contains a nonionic surfactant (C) having a polyoxyalkylene group, the proportion of the nonionic surfactant (C) having a polyoxyalkylene group in the nonvolatile content of the treating agent is preferably 5 to 35% by weight, more preferably 7 to 30% by weight, and even more preferably 10 to 25% by weight, from the viewpoints of hydrophilicity and foam-suppressing properties.

[0034] In the treatment agent for long-fiber nonwoven fabrics of the present invention, the proportion of dialkyl sulfosuccinate in the nonvolatile content of the treatment agent is preferably as low as possible from the viewpoints of hydrophilicity and foam suppression, and is preferably 0 to 20% by weight, more preferably 0 to 10% by weight, even more preferably 0 to 5% by weight, particularly preferably 0 to 1% by weight, and most preferably 0% by weight. In the treatment agent for long-fiber nonwoven fabrics of the present invention, the proportion of defoaming agent in the nonvolatile content of the treatment agent is preferably as low as possible from the viewpoint of hydrophilicity, and is preferably 10% by weight or less, 5% by weight or less, 2% by weight or less, 1% by weight or less, 0.1% by weight or less, and 0% by weight in this order. The defoaming agent is, for example, at least one selected from silicone, organic solvent, mineral oil, animal and vegetable oil, and silica.

[0035] [Continuous Fiber Nonwoven Fabric] The continuous fiber nonwoven fabric of the present invention is provided with the aforementioned treatment agent for continuous fiber nonwoven fabrics. The continuous fiber nonwoven fabric of the present invention is preferably a spunbonded nonwoven fabric. Spunbonded nonwoven fabrics are obtained by heating and melting a raw resin (high molecular weight polymer) in an extruder, extruding it through a spinneret with numerous fine holes, and stretching it by roll take-up or air sucker take-up to form continuous fibers. The continuous fibers are then collected on a net conveyor to form a web, which is then entangled by a method such as needle punching, water jetting, or ultrasonic waves, or by partially bonding the fibers by thermocompression bonding using an embossing roll, or by partially heat-sealing the fibers using air-through. The continuous fiber nonwoven fabric of the present invention includes not only single-layer spunbonded nonwoven fabrics but also composite sheets (e.g., SM, SMS, SMMS, etc.) of a spunbonded nonwoven fabric (S) and a meltblown nonwoven fabric (M).

[0036] Spunbond nonwoven fabrics have long fibers that are the constituent fibers of thermoplastic resins. Examples of thermoplastic resins include polyolefin resins, polyester resins, polyamide resins, acrylonitrile resins, vinyl resins, and vinylidene resins. Examples of polyolefin resins include polyethylene, polypropylene, and polybutene. Examples of polyester resins include polyethylene terephthalate and polybutylene terephthalate. Examples of polyamide resins include nylon. Examples of vinyl resins include polyvinyl chloride. Examples of vinylidene resins include polyvinylidene chloride. These resins can be used alone or in combination, or modified versions of these resins can be used.

[0037] From the viewpoint of spinnability, spunbond nonwoven fabrics are preferably formed from polypropylene resin, a polyolefin-based resin. From the viewpoints of smoothness, improved feel when in contact with the skin, and ease of breakage, polypropylene resins containing at least one of random copolymers, homopolymers, and block copolymers in an amount of 5% by weight to 100% by weight, more preferably 25% by weight to 80% by weight. These copolymers and homopolymers may be mixed, or other resins may be mixed, but a mixture of polypropylene homopolymers and random copolymers is preferred because of the reduced susceptibility to thread breakage during molding. Furthermore, random copolymers based on propylene components copolymerized with ethylene or A-olefins are preferred, with ethylene-propylene copolymer resins being particularly preferred. From the same viewpoint, polypropylene resins containing at least 5% by weight, and even more preferably at least 25% by weight, of ethylene-propylene copolymer resins are preferred. The ethylene-propylene copolymer resin preferably contains an ethylene concentration of 1 to 20% by weight.

[0038] The long-fiber nonwoven fabric of the present invention may have a structure of a single fiber or a composite fiber with two or more thermoplastic resin components. It may also be composed of a blend of single fibers made from different thermoplastic resin materials, or a blend of a single fiber and a composite fiber. The composite structure of the composite fiber may be any of a sheath-core type, a side-by-side type, an island-in-the-sea type, etc., and among these, a sheath-core type composite fiber, in which a low-melting-point resin is used as the sheath component and a high-melting-point component is used as the core component, is particularly preferred because it has good thermal adhesiveness and a stable thermally bonded state. In addition, composite fibers with a modified cross-section structure, a split type structure, or a hollow type structure may also be used.

[0039] The treatment agent for long-fiber nonwoven fabrics can be applied by known methods such as dipping, spraying, and coating (with a kiss coater or gravure coater) using a diluted treatment agent, and it is preferable to premix the agent and dilute it with a solvent such as water before applying it. When applying the treatment agent, the amount of the agent applied to the front and back of the nonwoven fabric may be different, if necessary.

[0040] When the treatment agent for long-fiber nonwoven fabrics is diluted with a solvent such as water and then applied, a drying step may be required. In this case, known methods utilizing convective heat transfer, conductive heat transfer, radiative heat transfer, etc. may be used, such as drying with hot air or infrared rays, or drying by thermal contact.

[0041] The long fiber nonwoven fabric has a basis weight of 8 g / m ２ ~30G / M ２ It is preferable that the ２ ~25g / m ２ It is more preferable that the weight per unit area is within the above range. When the weight per unit area is within the above range, the balance between strength and flexibility tends to be excellent. Furthermore, the nonwoven fabric of the present disclosure preferably has a thickness of 0.05 mm to 2.00 mm, more preferably 0.10 mm to 1.00 mm. The amount of the treatment agent for long-fiber nonwoven fabric applied must be in the range of 0.1 to 3 wt % based on the nonwoven fabric, and since the nonwoven fabric comes into direct contact with the human body, it is preferable to set it to the minimum necessary.

[0042] The long-fiber nonwoven fabric having the treatment agent for long-fiber nonwoven fabric of the present invention adhered thereto has excellent hydrophilicity and can therefore be suitably used in applications for conventionally known nonwoven fabrics, such as absorbent articles (disposable diapers, disposable pants, sanitary products, urine absorption pads, pet sheets, etc.), cosmetic materials (face masks, etc.), sanitary materials (poultices, sheets, towels, industrial masks, sanitary masks, hair caps, etc.), and packaging materials (oxygen absorbers, body warmers, hot compresses, food packaging materials).

[0043] The present invention will be described below using examples, but is not limited to these. The evaluation items and evaluation methods for each example and comparative example are as follows. The details of the treatment agents used in each example and comparative example and the evaluation results are summarized in Tables 1 to 3. In the details of the treatment agents, the blending ratios are all expressed in weight percent.

[0044] The nonvolatile content of the treatment agent for long-fiber nonwoven fabric of each Example and Comparative Example was prepared using the following components (A-1 to C-2). A-1: Sorbitan monolaurate (HLB: 10.8) A-2: Sorbitan monooleate (HLB: 8.2) B-1: Octyl phosphate potassium salt B-2: Lauryl phosphate potassium salt C-1-1: Polyoxyethylene (6 moles) polyoxypropylene (2 moles) alkyl (C12,13) ​​ether (random adduct) C-1-2: Polyoxyethylene (9 moles) polyoxypropylene (13 moles) octyl ether (block adduct) C-1-3: Polyoxyethylene (10 moles) polyoxypropylene (2 moles) alkyl (C12,14) ether (random adduct) C-2-1: PEG400 coconut fatty acid monoester C-2-2: PEG800 coconut fatty acid ester C-3-1: Polyoxyalkylene-modified silicone (KF-354L, manufactured by Shin-Etsu Chemical Co., Ltd., HLB: 16) C-3-2: Polyoxyalkylene-modified silicone (DOWSIL® SF8410, manufactured by Dow-Toray Industries, Inc., HLB: 6) C-3-3: Polyoxyalkylene-modified silicone (KF-615A, manufactured by Shin-Etsu Chemical Co., Ltd., HLB: 10) C-3-4: Polyoxyalkylene-modified silicone (DOWSIL® SH8400, manufactured by Dow-Toray Industries, Inc., HLB: 8) C-3-5: Polyoxyalkylene-modified silicone (KF-352A, manufactured by Shin-Etsu Chemical Co., Ltd., HLB: 7) The ingredients were mixed and stirred in the ratios shown in Tables 1 to 4 to prepare the non-volatile content of the treatment agent for long-fiber nonwoven fabrics of each Example and Comparative Example, and the following evaluations were performed.

[0045] [Wettability] This is a substitute evaluation for judging uniform adhesion to nonwoven fabric. Specifically, a dilution solution was prepared by diluting each water-permeable agent with ion-exchanged water so that the weight ratio of nonvolatile matter was 1.0% by weight. A 2 x 2 cm piece of Olifelt S20 (No. 103) manufactured by Nikke Co., Ltd. was floated in 100 ml of the dilution solution in a 100 ml glass beaker, and the time (in seconds) until the water-permeable agent left the liquid surface and began to settle was measured to evaluate uniform adhesion (temperature: 23°C). A shorter time until the water-permeable agent settled indicates better processability. The number of seconds was evaluated according to the following criteria: 5 is the best rating, and 3 or higher is practically usable: 5...less than 10 seconds, 4...10 to less than 20 seconds, 3...20 to less than 30 seconds, 2...30 to less than 60 seconds, 1...60 seconds or more.

[0046] [Low Foaming] The Ross Miles test was performed based on the method described in JIS K3362:2008, Section 8.5, Foaming Immediately and Foam Stability. Specifically, a dilution was prepared by diluting the water permeability imparting agent with ion-exchanged water so that the weight ratio of the nonvolatile content was 1.0% by weight. 200 ml of the dilution was poured into 50 ml of the dilution from 900 mm above for 30 seconds. The height of the foam generated was measured as the foam volume H1 [MM] immediately after the flow (10 seconds later) and the foam volume H2 [MM] 5 minutes after the flow. The test equipment, instruments, and operation methods were all in accordance with the contents described in JIS K3362, and the temperature of the measuring device and the diluted solution was adjusted to 25 ° C. in advance before the test. The test results were evaluated according to the following criteria. (Foam suppression) ◎: H1≦30MM, ○: 30MM150MM (Foam breaking) ◎: H2≦20MM, ○: 20MM<H2≦130MM, ×: H2>130MM Based on the above foam suppression and foam breaking properties, low foaming was evaluated according to the following criteria. The results are shown in the "Low Foaming" column in Tables 1 to 3. 5 is the best rating, and a rating of 3 or higher is suitable for practical use. (Low Foaming) 5: When both foam suppression and foam breaking are rated as ◎ 4: When foam suppression is ◯ and foam breaking is ◎ 3: When both foam suppression and foam breaking are ◯ 2: When either foam suppression or foam breaking is × 1: When both foam suppression and foam breaking are ×<h1>

[0047] [Repeated water permeability] Measurements were performed in accordance with EDANA (European Disposable and Nonwovens Manufacturers Association) standard NWSP070.8.RO(15), and the results of the third measurement were recorded. Those whose third measurement result was 3.5 seconds or less were judged as suitable for practical use and rated as O, and those whose third measurement result was more than 3.5 seconds were judged as ×.

[0048]

[0049]

[0050]

[0051]

[0052] As is clear from Tables 1 to 4, the treatment agents for long-fiber nonwoven fabrics in Examples 1 to 25 contain a sorbitan fatty acid ester (A) and at least one selected from a phosphate ester-type anionic surfactant (B) and a nonionic surfactant (C) having a polyoxyalkylene group. Because they have anti-foaming properties that satisfy the above-mentioned condition 1, they simultaneously provide good appearance and excellent wettability after prolonged storage, thereby resolving the problems of the present application. Furthermore, it was confirmed that the effects of the present application were also exhibited in diapers and sanitary napkins in which the nonwoven fabrics produced in the examples were used as topsheets. On the other hand, in the absence of the sorbitan fatty acid ester (A) (Comparative Examples 1 and 2) and the absence of anti-foaming properties that satisfy the above-mentioned condition 1 (Comparative Example 3), at least one of the problems of the present application could not be resolved.

Claims

1. A treatment agent for long-fiber nonwoven fabrics containing a sorbitan fatty acid ester (A) and at least one selected from a phosphate ester-type anionic surfactant (B) and a nonionic surfactant having a polyoxyalkylene group (C), which satisfies the following condition 1. Condition 1: The foaming power at an effective concentration of 1.0% by weight at 25°C, as measured by the Ross Miles test method, is 150 MM or less immediately after pouring and 130 MM or less 5 minutes after pouring.

2. The treatment agent for long-fiber nonwoven fabrics according to claim 1, wherein the alkyl group of said activator (B) has 6 to 12 carbon atoms, and said activator (C) has an alkyl group of 6 to 14 carbon atoms.

3. The treatment agent for long-fiber nonwoven fabrics according to claim 1 or 2, wherein the proportion of the sorbitan fatty acid ester (A) in the nonvolatile content of the treatment agent for long-fiber nonwoven fabrics is 60 to 95% by weight, and the total proportion of at least one surfactant selected from the phosphate ester-type anionic surfactant (B) and the nonionic surfactant having a polyoxyalkylene group (C) is 5 to 35% by weight.

4. The treatment agent for continuous fiber nonwoven fabrics according to any one of claims 1 to 3, wherein the felt settling test time is less than 30 seconds. Felt settling test time: The time it takes for a piece of Orifelt S20 (No. 103) manufactured by Nikke Co., Ltd. cut into a 2 cm x 2 cm piece to settle in a diluted solution with an effective concentration of 1.0 wt % at 23°C to settle.

5. The treatment agent for long-fiber nonwoven fabric according to any one of claims 1 to 4, wherein the sorbitan fatty acid ester is a sorbitan mono-fatty acid ester.

6. A filament nonwoven fabric to which the treatment agent for filament nonwoven fabrics according to any one of claims 1 to 5 has been applied.

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