Fiber treatment agent for nonwoven fabric, aqueous liquid of fiber treatment agent for nonwoven fabric, and fiber

Abstract

To reduce the rate of change in friction of a synthetic fiber even after long-term storage of the synthetic fiber to which a fiber treatment agent for a nonwoven fabric is attached, and to improve the wet friction characteristics of the synthetic fiber to which the fiber treatment agent for a nonwoven fabric is attached, and the emulsification stability and foam-inhibiting properties of the fiber treatment agent for a nonwoven fabric.SOLUTION: The fiber treatment agent for nonwoven fabric contains a phosphoric acid compound (A) and an alcohol (B). In a P-nuclear NMR measurement when the alkali over-neutralization pre-treatment is performed, when a total of P-nuclear NMR integral ratios attributed to phosphate ester P1, phosphate ester P2, phosphate ester P3, phosphate ester P4, phosphate ester P5, ortho-phosphoric acid, and salts thereof is 100%, P-nuclear NMR integral ratios attributed to P4 and P5 are 20% or more and 65% or less and 20% or more and 45% or less, and a value obtained by Equation (1) is 8 or less, the pH at 25 °C of a 1% by mass aqueous dilution is 5.0 or more and 8.0 or less, and the acid value per non-volatile content is 5 or more and less than 60.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a fiber treatment agent for nonwoven fabric, an aqueous solution of the fiber treatment agent for nonwoven fabric, and fibers. [Background technology]

[0002] It is generally known that the manufacturing process of nonwoven fabrics involves a spinning and drawing step of synthetic fibers, a finishing step, etc. Furthermore, in the spinning and drawing step, finishing step, etc., a treatment is sometimes carried out to adhere a synthetic fiber treating agent to the surface of the synthetic fibers in order to reduce friction, etc. of the synthetic fibers and improve antistatic properties, etc.

[0003] Conventionally, synthetic fiber treatment agents are known, as disclosed in Patent Documents 1 to 3. Patent Document 1 describes a fiber treatment agent for nonwoven fabric production that contains a specific alkyl phosphate ester and has an acid value (KOHmg / g) of less than 100 in the nonvolatile content.

[0004] Patent Document 2 describes a treatment agent for polyolefin synthetic fibers that contains a specific organic acid, an alkyl phosphate ester salt, and a polyoxyalkylene derivative.

[0005] Patent Document 3 describes that a fiber treatment agent for short fibers contains a specific alkyl phosphate ester. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2023 / 149326 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-210693 [Patent Document 3] Japanese Patent Publication No. 2020-73741 Summary of the Invention [Problem to be solved by the invention]

[0007]

[0003] Synthetic fiber treatment agents used in nonwoven fabrics, i.e., fiber treatment agents for nonwoven fabrics, are required to exhibit a small rate of change in friction of the synthetic fibers even after long-term storage of the synthetic fibers to which the treatment agent is applied. Further improvements are also required in the wet friction characteristics of the synthetic fibers to which the fiber treatment agent is applied, the emulsion stability of the fiber treatment agent for nonwoven fabrics, and the foam suppression properties. [Means for solving the problem]

[0008] As a result of research aimed at solving the above problems, the present inventors have found that a fiber treatment agent for nonwoven fabrics containing a specific phosphoric acid compound and an alcohol is exactly suitable. Various aspects for solving the above problems will be described.

[0009] The fiber treatment agent for nonwoven fabrics in aspect 1 is a fiber treatment agent for nonwoven fabrics containing the following phosphoric acid compound (A) and the following alcohol (B), In P nuclear NMR measurement of the fiber treatment agent for nonwoven fabrics after alkaline overneutralization pretreatment, when the total of the P nuclear NMR integral ratios attributable to phosphate ester P1, phosphate ester P2, phosphate ester P3, phosphate ester P4, phosphate ester P5, orthophosphoric acid and salts thereof is taken as 100%, the P nuclear NMR integral ratio attributable to phosphate ester P4 is 20% or more and 65% or less, the P nuclear NMR integral ratio attributable to phosphate ester P5 is 20% or more and 45% or less, and the value calculated by the following mathematical formula (1) is 8 or less, the pH of a 1% by mass aqueous solution of the fiber treatment agent for nonwoven fabric at 25°C is 5.0 or more and 8.0 or less; The fiber treatment agent for nonwoven fabrics is characterized in that the acid value per nonvolatile content of the fiber treatment agent for nonwoven fabrics is 5 KOH-mg / g or more and less than 60 KOH-mg / g.

[0010] Phosphate compound (A): Contains a phosphate ester P3 represented by the following formula (3), a phosphate ester P4 represented by the following formula (4), a phosphate ester P5 represented by the following formula (5), and orthophosphoric acid, and optionally further contains at least one selected from a phosphate ester P1 represented by the following formula (1) and a phosphate ester P2 represented by the following formula (2).

[0011] [ka]

[0012] (In Chemical Formula 1, M 1 ,M 2 ,M 3 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0013] [ka]

[0014] (In Chemical Formula 2, R 1 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 4 ,M 5 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0015] [ka]

[0016] (In Chemical Formula 3, R 2 ,R 3 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 6 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0017] [ka]

[0018] (In Chemical Formula 4, R 4 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 7 ,M 8 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0019] [ka]

[0020] (In Chemical Formula 5, R 5 ,R 6 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 9 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0021]

number

[0022] Alcohol (B): Aliphatic alcohol with 8 to 18 carbon atoms. Aspect 2 is the same as aspect 1, wherein the value calculated by the formula (1) is 3.5 or less.

[0023] In a third aspect, in the fiber treatment agent for nonwoven fabrics according to the first or second aspect, the P nucleus NMR integral ratio attributable to the phosphate ester P3 is 6.5% or more and 40% or less. In aspect 4, in the fiber treatment agent for nonwoven fabrics according to any one of aspects 1 to 3, the sum of the P nucleus NMR integral ratios attributable to the phosphate ester P2 and the phosphate ester P3 is more than 0% and less than 20%.

[0024] Aspect 5 is the fiber treatment agent for nonwoven fabrics according to any one of Aspects 1 to 4, wherein, when the content of the phosphoric acid compound (A) and the content of the alcohol (B) are taken as 100 mass%, the content of the phosphoric acid compound (A) is 85 mass% or more and 99.9 mass% or less, and the content of the alcohol (B) is 0.1 mass% or more and 15 mass% or less.

[0025] A sixth aspect is the fiber treating agent for nonwoven fabric according to any one of the first to fifth aspects, which satisfies at least one of the following two conditions. Condition 1: The alcohol (B) contains two or more types of alcohols having different carbon numbers.

[0026] Condition 2: Contains a fatty acid (C) having 12 to 20 carbon atoms. A seventh aspect is the fiber treating agent for nonwoven fabric according to any one of the first to sixth aspects, further comprising the following nonionic surfactant (D).

[0027] Nonionic surfactant (D): At least one selected from a compound in which a total of 5 to 100 moles of alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a monohydric aliphatic alcohol having 22 to 50 carbon atoms, and an ester compound of a polyglycerin having a condensation degree of 3 to 12 and a saturated fatty acid having 12 to 18 carbon atoms.

[0028] In aspect 8, the fiber treatment agent for nonwoven fabrics according to aspect 7 contains the phosphoric acid compound (A) in an amount of 20% by mass or more and 80% by mass or less, the alcohol (B) in an amount of 0.1% by mass or more and 10% by mass or less, and the nonionic surfactant (D) in an amount of 10% by mass or more and 75% by mass or less, where the total content of the phosphoric acid compound (A), the alcohol (B), and the nonionic surfactant (D) is 100% by mass.

[0029] A ninth aspect of the present invention relates to an aqueous solution of a fiber treatment agent for nonwoven fabric, wherein the fiber treatment agent for nonwoven fabric according to any one of the first to eighth aspects has a nonvolatile content concentration of 0.1% by mass or more and 10% by mass or less.

[0030] The fiber of the tenth aspect is characterized in that the fiber treating agent for nonwoven fabric according to any one of the first to eighth aspects is adhered to the fiber. The fiber of an eleventh aspect is characterized in that the fiber of the tenth aspect is a polyolefin-based synthetic fiber. [Effects of the Invention]

[0031] According to the present invention, it is possible to reduce the rate of change in friction of synthetic fibers to which a fiber treatment agent for nonwoven fabric has been applied, even after long-term storage of the synthetic fibers, and to improve the wet friction characteristics of the synthetic fibers to which the fiber treatment agent for nonwoven fabric has been applied, as well as the emulsion stability and foam suppression properties of the fiber treatment agent for nonwoven fabric. DETAILED DESCRIPTION OF THE INVENTION

[0032] First Embodiment A first embodiment of the fiber treatment agent for nonwoven fabrics (hereinafter simply referred to as the treatment agent) of the present invention will be described below. The treatment agent of this embodiment contains the following phosphoric acid compound (A) and the following alcohol (B).

[0033] (Phosphate Compound (A)) The phosphoric acid compound (A) contains a phosphoric acid ester P3 represented by the following formula (3), a phosphoric acid ester P4 represented by the following formula (4), a phosphoric acid ester P5 represented by the following formula (5), and orthophosphoric acid, and optionally further contains at least one selected from a phosphoric acid ester P1 represented by the following formula (1) and a phosphoric acid ester P2 represented by the following formula (2).

[0034] [ka]

[0035] (In Chemical Formula 1, M 1 ,M 2 ,M 3: Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0036] [ka]

[0037] (In Chemical Formula 2, R 1 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 4 ,M 5 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0038] [ka]

[0039] (In Chemical Formula 3, R 2 ,R 3 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 6 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0040] [ka]

[0041] (In Chemical Formula 4, R 4 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 7 ,M 8 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium.

[0042] [ka]

[0043] (In Chemical Formula 5, R 5 ,R 6 : an alkyl or alkenyl group having 8 to 12 carbon atoms. M 9 : Hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium. (alkali metals) In the phosphate compound (A), M 1 ~M 9 The alkali metal constituting the compound is not particularly limited, and examples thereof include sodium, potassium, and lithium.

[0044] (alkaline earth metals) M 1 ~M 9 The alkaline earth metal constituting the element (I) is not particularly limited, and examples thereof include calcium, magnesium, beryllium, strontium, and barium.

[0045] The above "alkaline earth metal (1 / 2)" is a divalent alkaline earth metal, so M 1 ~M 9 This means that 1 / 2 mole of the compound is added. (organic amine) M 1 ~M 9 The organic amine constituting the formula (I) is not particularly limited, and examples thereof include primary amines such as methylamine, ethylamine, butylamine, octylamine, laurylamine, octadecylamine (also called stearylamine), octadecenylamine, and coconut amine.

[0046] (phosphonium) M 1 ~M 9The phosphonium constituting the formula (I) is not particularly limited, and examples thereof include quaternary phosphoniums such as tetramethylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, tetraoctylphosphonium, dibutyldihexylphosphonium, trihexyltetradecylphosphonium, triethyloctylphosphonium, trioctylmethylphosphonium, and triphenylmethylphosphonium.

[0047] The above M 1 ~M 9 The alkali metals, alkaline earth metals, organic amines, ammonium, and phosphonium constituting the compound (I) may be used singly or in appropriate combination of two or more.

[0048] (Alkyl group having 8 to 12 carbon atoms) R 1 ~R 6 The alkyl group having 8 to 12 carbon atoms constituting the group is not particularly limited, and may be a straight-chain alkyl group or a branched-chain alkyl group.

[0049] Specific examples of the straight-chain alkyl group include an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. Specific examples of the branched alkyl group include an isooctyl group, an isononyl group, an isodecyl group, an isoundecyl group, and an isododecyl group.

[0050] (Alkenyl group having 8 to 12 carbon atoms) R 1 ~R 6 The alkenyl group having 8 to 12 carbon atoms constituting the formula (I) is not particularly limited, and may be a straight-chain alkenyl group or a branched-chain alkenyl group.

[0051] Specific examples of the straight-chain alkenyl group include an octenyl group, a nonenyl group, a decenyl group, an undecenyl group, and a dodecenyl group. Specific examples of the alkenyl group having a branched chain include an isooctenyl group, an isononenyl group, an isodecenyl group, an isoundecenyl group, and an isododecenyl group.

[0052] Above R 1 ~R 6 The alkyl group and alkenyl group each having 8 to 12 carbon atoms may be used alone or in appropriate combination of two or more kinds.

[0053] The orthophosphoric acid contained in the phosphoric acid compound (A) may form a salt, such as a salt with the above-mentioned alkali metals or alkaline earth metals.

[0054] (Method for producing phosphoric acid compound (A)) The method for producing the phosphoric acid compound (A) is not particularly limited, and any known production method can be used. For example, the phosphoric acid compound (A) can be produced by reacting a raw material aliphatic alcohol with phosphoric anhydride such as diphosphorus pentoxide to obtain a phosphoric acid oxide (hereinafter also referred to as a phosphorylation reaction), and then neutralizing the obtained phosphoric acid oxide.

[0055] The aliphatic alcohol is R 1 ~R 6 An alcohol having an alkyl or alkenyl group having 8 to 12 carbon atoms can be used. The aliphatic alcohol is preferably dehydrated in advance, as this makes it easier to prevent decomposition of phosphoric anhydride due to water in the raw material.

[0056] The atmosphere for the reaction of the aliphatic alcohol and phosphoric anhydride is not particularly limited, and a nitrogen atmosphere, an air atmosphere, or the like can be adopted. A nitrogen atmosphere is preferred because it makes it easier to suppress decomposition of phosphoric anhydride due to moisture in the reaction atmosphere.

[0057] The conditions for the phosphorylation reaction are not particularly limited, but it is preferable to carry out the reaction at a temperature of 65° C. to 85° C. for 1 hour to 6 hours. It is also preferable to prevent the synthesized phosphoric acid oxide from coming into contact with moisture, as this would cause the phosphoric acid esters P2 and P3 to be easily decomposed.

[0058] The conditions for the neutralization are not particularly limited, but it is preferable to carry out the neutralization for 3 to 9 hours at a temperature of 85 to 95° C. If the neutralization temperature is less than 85° C., the content of the phosphate ester P2 tends to be high.

[0059] (Alcohol (B)) The alcohol (B) is an aliphatic alcohol having 8 to 18 carbon atoms. Specific examples of the alcohol (B) include octanol, nonanol, decanol, undecanol, dodecanol (lauryl alcohol), tridecanol, tetradecanol, pentadecanol, hexadecanol (cetyl alcohol), heptadecanol, and octadecanol (stearyl alcohol).

[0060] The alcohol (B) may be a straight-chain aliphatic alcohol or a branched-chain aliphatic alcohol. The alcohol (B) may be used singly as one type of alcohol (B) or as an appropriate combination of two or more types of alcohol (B).

[0061] The alcohol (B) preferably contains two or more types of alcohol (B) having different carbon numbers. When two or more types of alcohol (B) having different carbon numbers are contained, the foam suppressing properties of the treatment agent can be further improved.

[0062] (Ratio of phosphoric acid compound (A) and alcohol (B)) The content ratios of the phosphoric acid compound (A) and the alcohol (B) in the treatment agent are not particularly limited, but it is preferable that the phosphoric acid compound (A) is contained in an amount of 85% by mass to 99.9% by mass and the alcohol (B) is contained in an amount of 0.1% by mass to 15% by mass, assuming that the content ratios of the phosphoric acid compound (A) and the alcohol (B) are 100% by mass.

[0063] When the content ratio of the phosphoric acid compound (A) and the alcohol (B) in the treatment agent is within the above range, the initial hydrophilicity of the synthetic fiber to which the treatment agent is applied can be further improved.

[0064] (P nucleus NMR integral ratio) In P nuclear NMR measurement of the treatment agent after alkaline overneutralization pretreatment, when the total of the P nuclear NMR integral ratios attributable to phosphate ester P1, phosphate ester P2, phosphate ester P3, phosphate ester P4, phosphate ester P5, orthophosphoric acid and its salts is taken as 100%, the P nuclear NMR integral ratio attributable to phosphate ester P4 is 20% or more and 65% or less, and the P nuclear NMR integral ratio attributable to phosphate ester P5 is 20% or more and 45% or less.

[0065] Furthermore, the value determined by the following formula (1) is not more than 8. It is preferable that the value determined by the following formula (1) is not more than 3.5.

[0066]

number

[0067] When the value obtained from the formula (1) is 8 or less, the rate of change in friction of the synthetic fiber can be reduced even after the synthetic fiber with the treatment applied thereto is stored for a long period of time. Furthermore, when the value obtained from the formula (1) is 3.5 or less, the rate of change in friction can be further reduced.

[0068] The frictional properties of synthetic fibers coated with a treatment agent are thought to be significantly affected by the increase in orthophosphoric acid due to the decomposition of phosphate ester P1 and phosphate ester P2 over time. 2 moles of orthophosphoric acid are produced from 1 mole of phosphate ester P1 through decomposition. Similarly, 1 mole of phosphate ester P2 through decomposition produces 1 mole of orthophosphoric acid. Therefore, the rate of change in friction of synthetic fibers can be evaluated using the above formula (1), taking into account the effect of orthophosphoric acid production.

[0069] Here, the term "alkali perneutralization pretreatment" refers to a pretreatment in which an excess amount of alkali is added to the phosphate ester and orthophosphoric acid contained in the phosphoric acid compound (A). Specific examples of the alkali include alkali metal hydroxides. The alkali may be the same as or different from the alkali used in synthesizing the phosphate ester salt. Specific examples of alkali metal hydroxides include sodium hydroxide and potassium hydroxide. In P nuclear NMR measurement, by performing alkali perneutralization pretreatment, the peaks assigned to the phosphate esters P1 to P5, orthophosphoric acid, and their salts can be clearly separated. The method for measuring the P nuclear NMR integral ratio will be described later.

[0070] The P nucleus NMR integral ratio attributable to the phosphate ester P3 is preferably 6.5% or more and 40% or less. Furthermore, it is preferable that the total of the P nucleus NMR integral ratios attributable to the phosphate esters P2 and P3 is more than 0% and less than 20%.

[0071] When the P nucleus NMR integral ratio assigned to the phosphate ester P3 is 6.5% or more and 40% or less, emulsion stability can be further improved. Furthermore, when the sum of the P nucleus NMR integral ratios attributable to phosphate esters P2 and P3 is more than 0% and less than 20%, the friction between the synthetic fiber to which the treatment agent is applied and the metal in a wet state can be further reduced, in other words, the friction characteristics in a wet state can be further improved.

[0072] (pH of treatment agent) The pH of a 1% by mass water dilution of the treatment agent at 25°C is 5.0 or more and 8.0 or less. A pH of 5.0 or higher and 8.0 or lower is weakly acidic to neutral, so when nonwoven fabrics containing fibers with the treatment agent attached are used as sanitary materials that come into contact with the skin, they can cause less irritation to the skin.

[0073] The method for adjusting the pH of the treatment agent is not particularly limited. For example, the pH can be adjusted by adjusting the acid value of the treatment agent. The pH of the treatment agent can also be adjusted by using a pH adjuster as the other component (E) described below.

[0074] The method for measuring pH is not particularly limited, and for example, it can be measured using a known pH measuring device (desktop pH meter F-72 manufactured by Horiba Ltd.). (Acid value of treatment agent) The acid value per nonvolatile content of the treatment agent is 5 KOH-mg / g or more and less than 60 KOH-mg / g. When the acid value per nonvolatile content of the treatment agent is in this range, the emulsion stability of the treatment agent can be improved.

[0075] The acid value per unit of non-volatile content of the treatment agent is calculated by dissolving the non-volatile content of the treatment agent in a mixed solvent of ethanol / xylene = 1 / 2 (volume ratio), setting it in a potentiometric titrator, and titrating it with a 0.1 mol / L potassium hydroxide methanol standard solution using the following formula.

[0076] Acid value (KOH-mg / g)=(R×f×56.11×0.1) / S In the formula, f: Factor of 0.1 mol / L potassium hydroxide methanol standard solution S: Sample amount (g, solids equivalent) R: Amount (mL) of 0.1 mol / L potassium hydroxide methanol standard solution used to reach the inflection point The non-volatile content of the treatment agent refers to the mass of the bone-dry product obtained by heat-treating the treatment agent at 105°C until it reaches a constant weight and then thoroughly removing volatile substances.

[0077] (Fatty acids with 12 to 20 carbon atoms (C)) The treatment agent may contain a fatty acid (C) having 12 or more and 20 or less carbon atoms. Specific examples of fatty acids (C) include dodecanoic acid (lauric acid), tridecanoic acid, tetradecanoic acid (myristic acid), pentadecanoic acid, hexadecanoic acid (palmitic acid), heptadecanoic acid, octadecanoic acid (stearic acid), nonadecanoic acid, and icosanoic acid.

[0078] As the fatty acid (C), one type of fatty acid (C) may be used alone, or two or more types of fatty acids (C) may be used in appropriate combination. When the treatment agent contains a fatty acid (C) having 12 to 20 carbon atoms, the foam suppressing properties of the treatment agent can be further improved.

[0079] The content of the fatty acid (C) is not particularly limited, but it is preferably contained in a proportion of 0% by mass or more and 2% by mass or less in the nonvolatile content of the treatment agent. The treatment agent preferably satisfies at least one of the following two conditions.

[0080] Condition 1: Contains two or more alcohols (B) with different carbon numbers. Condition 2: Contains a fatty acid (C) having 12 to 20 carbon atoms. If the treatment agent satisfies at least one of the above conditions 1 and 2, the foam suppressing properties of the treatment agent can be further improved.

[0081] (Nonionic surfactant (D)) The treatment agent preferably further contains at least one selected from the following nonionic surfactants (D).

[0082] Specific examples of the nonionic surfactant (D) include a compound in which a total of 5 to 100 moles of alkylene oxide having 2 to 4 carbon atoms is added to 1 mole of a monohydric aliphatic alcohol having 22 to 50 carbon atoms, and an ester compound of a polyglycerol having a condensation degree of 3 to 12 and a saturated fatty acid having 12 to 18 carbon atoms.

[0083] When the treatment agent contains the above-mentioned nonionic surfactant (D), the durable hydrophilicity of the synthetic fiber to which the treatment agent is attached can be further improved. (Contents of phosphoric acid compound (A), alcohol (B), and nonionic surfactant (D)) The contents of the phosphoric acid compound (A), alcohol (B), and nonionic surfactant (D) in the treatment agent are not particularly limited. When the contents of the phosphoric acid compound (A), alcohol (B), and nonionic surfactant (D) are taken as 100% by mass, the treatment agent preferably contains 20% to 80% by mass of the phosphoric acid compound (A), 0.1% to 10% by mass of the alcohol (B), and 10% to 75% by mass of the nonionic surfactant (D).

[0084] When the content ratios of the phosphate compound (A), the alcohol (B), and the nonionic surfactant (D) in the treatment agent are within the above numerical ranges, it becomes easy to set the acid value of the treatment agent and the value calculated by formula (1) within the above numerical ranges.

[0085] (Other ingredients (E)) The treatment agent may contain other components (E), such as stabilizers, antistatic agents, binders, antioxidants, ultraviolet absorbers, surfactants other than the nonionic surfactant (D), pH adjusters, and alcohols other than the alcohol (B), which are typically used in treatment agents.

[0086] Specific examples of the other component (E) include lactic acid, dioctyl sulfosuccinate sodium salt, dodecyl sulfonate sodium salt, polyether-modified silicone, and the like.

[0087] The content of the other component (E) in the nonvolatile content of the treatment agent is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less. The other component (E) may be 0% by mass.

[0088] (Preservation form) The treatment agent may be configured as a one-component treatment agent containing the above-mentioned components (A) to (E), or from the viewpoint of improving the formulation stability, it may be configured as a two-component treatment agent or a three-component treatment agent.

[0089] (solvent) The treatment agent of this embodiment is mixed with a solvent as needed to prepare a fiber treatment agent-containing composition for nonwoven fabrics (hereinafter also referred to as a "treatment agent-containing composition"), and the treatment agent may be stored or distributed in the form of a treatment agent-containing composition.

[0090] The solvent has a boiling point of 105° C. or less at 1 atmosphere. Examples of the solvent include water and organic solvents. Specific examples of water include ion-exchanged water, distilled water, hard water, soft water, etc. Among these, it is preferable to use ion-exchanged water or distilled water.

[0091] Specific examples of organic solvents include lower alcohols such as ethanol and propanol, and low-polarity solvents such as hexane. These solvents may be used alone or in appropriate combination of two or more. Among these, polar solvents such as water and lower alcohols are preferred from the viewpoint of excellent dispersibility or solubility of each component, and water is more preferred from the viewpoint of excellent handleability.

[0092] <Actions and Effects of the First Embodiment> (1-1) The treatment agent of the first embodiment contains the above-mentioned phosphoric acid compound (A) and alcohol (B). The P NMR integral ratio attributable to phosphoric acid ester P4 is 20% to 65% and the P NMR integral ratio attributable to phosphoric acid ester P5 is 20% to 45%. The value calculated by formula (1) is 8 or less. The acid value per nonvolatile content of the treatment agent is 5 KOH-mg / g or more and less than 60 KOH-mg / g. Therefore, even after long-term storage of synthetic fibers to which the treatment agent is applied, the rate of change in friction of the synthetic fibers can be reduced. Furthermore, the wet friction characteristics, initial hydrophilicity, durable hydrophilicity, emulsion stability of the treatment agent, and foam suppression properties of the synthetic fibers to which the treatment agent is applied can be improved.

[0093] (1-2) Furthermore, by including the above-mentioned nonionic surfactant (D), the durable hydrophilicity of the synthetic fiber to which the treatment agent is attached can be further improved. (1-3) By using the treatment agent of the first embodiment, it is possible to produce a nonwoven fabric that can be suitably used for final products such as diapers and wet tissues as sanitary products.

[0094] Second Embodiment Next, a second embodiment of the aqueous solution of the fiber treatment agent for nonwoven fabric of the present invention (hereinafter simply referred to as the aqueous solution) will be described. The following description will focus on the differences from the first embodiment.

[0095] The aqueous liquid of this embodiment contains the treatment agent and water. The aqueous liquid is used as an emulsion by mixing the treatment agent and water. Specific examples of water that can be used are the same as the water used as the solvent.

[0096] The method for preparing the aqueous liquid is not particularly limited, and examples thereof include a method in which a predetermined amount of the treatment agent is added to a pre-measured amount of water.Furthermore, the aqueous liquid can also be prepared by a known mechanical emulsification method using a known homomixer, homogenizer, or the like.

[0097] The concentration of the treatment agent in the aqueous liquid is not particularly limited, but the concentration of the treatment agent is preferably, for example, 0.1% by mass or more and 10% by mass or less in terms of the non-volatile content of the treatment agent. When the concentration of the treatment agent in the aqueous liquid is within the above range, emulsion stability is easily improved.

[0098] <Actions and Effects of the Second Embodiment> In addition to the functions and effects of the first embodiment, the second embodiment has the following functions and effects.

[0099] (2-1) The aqueous liquid of the second embodiment contains the treatment agent and water. Therefore, the treatment agent can be applied to the synthetic fibers for nonwoven fabric in the form of an emulsion. Furthermore, the inclusion of water as a solvent improves the handleability of the aqueous liquid.

[0100] Third Embodiment Next, a third embodiment of the fiber of the present invention will be described. The fiber of this embodiment is a treated fiber having the treatment agent of the first embodiment adhered to its surface. By adhering the treatment agent to the surface of the fiber, a fiber exhibiting the effects of the present invention can be obtained.

[0101] The type of fiber is not particularly limited, but examples include (1) polyester fibers such as polyethylene terephthalate (PET), polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene terephthalate-isophthalate, polyether polyester, polylactic acid, and composite fibers containing these polyester resins, (2) polyamide fibers such as nylon 6 and nylon 66, (3) polyacrylic fibers such as polyacrylic and modacrylic, and (4) polyolefin fibers such as polyethylene and polypropylene. Among these, polyolefin fibers (hereinafter also referred to as polyolefin synthetic fibers) are preferred.

[0102] The polyolefin synthetic fiber may be a composite fiber with a core-sheath structure. That is, the composite fiber may be a composite fiber in which either the core or the sheath, or both, are polyolefin fibers. Specifically, the composite fiber may be a polyethylene / polypropylene composite fiber in which the sheath is polyethylene and the core is polypropylene, or a polyethylene / polyester composite fiber in which the sheath is polyethylene and the core is polyester.

[0103] The treatment agent of this embodiment is applied to nonwoven fabric applications. As long as a treated nonwoven fabric having the treatment agent of this embodiment adhered to its surface can be obtained, the treatment agent may be adhered to the fiber surface before the nonwoven fabric is produced, or may be adhered to the fiber surface after the nonwoven fabric is produced.

[0104] The length of the fibers is not particularly limited, and the present invention can be applied to both short and long fibers, but is preferably applied to short fibers. That is, the polyolefin synthetic fibers of the present embodiment are preferably polyolefin short fibers.

[0105] The short fibers are generally called staple fibers and do not include long fibers generally called filaments. The length of the short fibers is not particularly limited as long as it corresponds to short fibers in this technical field, but is, for example, 100 mm or less, preferably 30 mm to 70 mm.

[0106] (Treatment agent adhesion treatment) There are no particular restrictions on the proportion of the treatment agent of the first embodiment applied to the fibers. The treatment agent is applied so that the non-volatile content of the treatment agent is preferably 0.01% by mass to 10% by mass, more preferably 0.1% by mass to 3% by mass, relative to the fibers. This configuration allows the efficacy of each component to be effectively exerted. There are also no particular restrictions on the method for applying the aqueous liquid, and known methods can be used depending on the type, shape, and application of the fibers, such as roller oiling, guide oiling using a metering pump, immersion oiling, and spray oiling. When the immersion oiling method is used, the immersion time is preferably 1 minute to 5 minutes.

[0107] The fibers to which the aqueous liquid has been applied may be dried or heat-treated using a known method. The drying or heat-treatment volatilizes the solvent, such as water, to obtain fibers to which the components contained in the treatment agent are attached. The fibers to which the components of the treatment agent are attached can effectively exhibit the efficacy for use in nonwoven fabrics.

[0108] (Nonwoven fabric manufacturing method) The type of nonwoven fabric is not particularly limited, but examples thereof include spunbond nonwoven fabrics produced by the spunbond method. Furthermore, examples of web formation methods other than the spunbond method include dry methods such as carding and airlaid methods when the raw material fibers are short fibers, and wet methods such as papermaking methods. Furthermore, examples of methods for bonding fibers include meltblown methods and flash spinning methods when the raw material fibers are long fibers. Furthermore, examples of methods for bonding fibers include chemical bonding, thermal bonding, needle punching, spunlace, and stitch bonding.

[0109] The polyolefin synthetic fiber of the present embodiment may be used to produce a nonwoven fabric by the following method. Specifically, the nonwoven fabric can be obtained by the following steps. Step 1: A step of attaching the treatment agent of the first embodiment to polyolefin-based synthetic fibers.

[0110] Step 2: A step of passing the polyolefin synthetic fibers to which the treatment agent has been applied in step 1 through a roller carding machine to obtain a roller carded web. Step 2 is also called a carding step. Step 3: A step of producing a nonwoven fabric by subjecting the roller-carded web obtained in Step 2 to a hot air treatment to fuse the fibers together. Step 3 is also called an air-through step.

[0111] A nonwoven fabric can be produced through the above steps. The nonwoven fabric obtained through the air-through process is also called a thermal-bonded nonwoven fabric. <Actions and Effects of the Third Embodiment> (3-1) The polyolefin synthetic fiber is coated with the treatment agent of the first embodiment. Therefore, the rate of change in friction is small even after long-term storage. In addition, the wet friction characteristics of the polyolefin synthetic fiber are improved. [Example]

[0112] Examples will be given below to more specifically illustrate the configuration and effects of the present invention, but the present invention is not limited to these examples. In the following examples and comparative examples, parts mean parts by mass.

[0113] Test Category 1 (Preparation of fiber treatment agents for nonwoven fabrics) Example 1 As shown in Table 1, 23.2 parts (mass%) of the phosphate compounds (A-1) and (A-2) shown in Table 2 were used as the phosphate compounds (A), 0.28 parts (mass%) of lauryl alcohol (B-1) and 0.28 parts (mass%) of octyl alcohol (B-2) as the alcohol (B), 0.24 parts (mass%) of stearic acid (C-2) as the fatty acid (C), and 30 parts (mass%) of polyoxyethylene (40 mol) triacontyl ether (D-1) and 30 parts (mass%) of polyoxyethylene (50 mol) tetracontyl ether (D-2) as the nonionic surfactant (D). A total of 100 parts (mass%) was diluted with 900 parts of hot water at 70 ° C. in a beaker. The mixture was stirred until homogeneous, and a 10% by mass aqueous solution of the fiber treatment agent for nonwoven fabrics of Example 1 was prepared.

[0114] (Examples 2 to 25, Comparative Examples 1 to 12) The treatment agents of Examples 2 to 25 and Comparative Examples 1 to 12 were prepared in the same manner as the treatment agent of Example 1, containing the phosphoric acid compound (A), alcohol (B), fatty acid (C), nonionic surfactant (D), and other component (E) in the proportions shown in Table 1.

[0115] The type and content of the phosphate compound (A), the type and content of the alcohol (B), the type and content of the fatty acid (C), the type and content of the nonionic surfactant (D), and the type and content of the other component (E) are shown in the "Phosphate Compound (A)," "Alcohol (B)," "Fatty Acid (C)," "Nonionic Surfactant (D)," and "Other (E)" columns of Table 1. The value calculated by formula (1), the acid value per nonvolatile content of the treatment agent, and the pH of a 1% by mass water dilution of the treatment agent at 25°C are shown in the "Value of Formula 1," "Acid Value of Treatment Agent," and "pH" columns of Table 1.

[0116] [Table 1]

[0117] Details of the phosphoric acid compound (A) shown in Table 1 are as follows. <Phosphate Compound (A)> The phosphoric acid compounds (A) used were A-1 to A-16 listed in Table 2. The type of phosphoric acid compound (A) is shown in the "Type of phosphoric acid compound (A)" column of Table 2. The production conditions, acid value, and P nucleus NMR integral ratio of the phosphoric acid compound (A) are shown in the "Production conditions (A / B / C / D)" column, the "Acid value of phosphoric acid compound (A)" column, and the "P nucleus NMR integral ratio (%)" column of Table 2, respectively.

[0118] [Table 2]

[0119] Table 3 shows details of production conditions A to D for the phosphoric acid compound (A) shown in Table 2. In Table 3, the "Alcohol dehydration" column indicates whether or not the raw material alcohol was dehydrated. The "Synthesis environment" column indicates the atmosphere for the phosphorylation reaction. The "Phosphorylation conditions" column indicates the temperature and time for the phosphorylation reaction. The "Water addition after phosphorylation" column indicates whether or not water was added after the phosphorylation reaction. The "Neutralization conditions" column indicates the temperature and time for neutralizing the phosphoric acid.

[0120] [Table 3]

[0121] The production conditions A to D of the phosphoric acid compound (A) are described in further detail below. (Manufacturing condition A) In production condition A, the raw material alcohol used was one that had been dehydrated under reduced pressure at 105°C. The raw material alcohol was placed in a four-neck flask, and diphosphorus pentoxide was gradually added to it under a nitrogen atmosphere. The phosphorylation reaction was carried out by stirring at 70±3°C for 3 hours. The phosphoric acid obtained in the phosphorylation reaction was gradually added to an aqueous potassium hydroxide solution, and the phosphoric acid was neutralized by stirring at 90±3°C for 6 hours, synthesizing a phosphate ester compound.

[0122] (Manufacturing condition B) In manufacturing condition B, the raw material alcohol was used as is after opening the reagent bottle. The phosphorylation reaction was carried out in the atmosphere. After opening the reagent bottle, diphosphorus pentoxide was left in the atmosphere (room temperature: approximately 27°C, relative humidity: approximately 80%) until the entire amount was added. It took approximately 30 minutes from the start to the end of adding diphosphorus pentoxide. The phosphate ester compound was synthesized under the same conditions as manufacturing condition A.

[0123] (Manufacturing condition C) In manufacturing condition C, the raw material alcohol was used as is after opening the reagent bottle. The phosphorylation reaction was carried out in the atmosphere. After opening the reagent bottle, diphosphorus pentoxide was left in the atmosphere (room temperature: approximately 27°C, relative humidity: approximately 80%) until the entire amount was added. It took approximately 30 minutes from the start to the end of adding diphosphorus pentoxide. The phosphorylation reaction was carried out with stirring at 70±3°C for 3 hours. The phosphorus oxide obtained in the phosphorylation reaction was gradually added to an aqueous potassium hydroxide solution, and the solution was stirred at 70±3°C for 3 hours to neutralize the phosphorus oxide. Otherwise, the phosphate ester compound was synthesized under the same conditions as manufacturing condition A.

[0124] (Manufacturing condition D) In production condition D, the raw material alcohol was used as is after opening the reagent bottle. The phosphorylation reaction was carried out under atmospheric pressure. After opening the reagent bottle, diphosphorus pentoxide was left in the atmosphere (room temperature: approximately 27°C, relative humidity: approximately 80%) until the entire amount was added. It took approximately 30 minutes from the start of addition of diphosphorus pentoxide to its completion. The phosphorylation reaction was carried out with stirring at 70±3°C for 3 hours. After the phosphorylation reaction was completed, water was added in an amount of 1.8% by mass of the total amount of the raw material alcohol and diphosphorus pentoxide, and the mixture was stirred at 70±3°C for 1 hour to obtain a phosphorus oxide. The obtained phosphorus oxide was gradually added to an aqueous potassium hydroxide solution and neutralized by stirring at 70±3°C for 3 hours. The phosphorus ester compound was otherwise synthesized under the same conditions as production condition A.

[0125] In addition, under each of the production conditions A to D, the compounding ratio of the raw material alcohol to diphosphorus pentoxide, the conditions for neutralizing the phosphoric acid oxide, etc. may be further adjusted as appropriate within the scope of common general technical knowledge. By adjusting these conditions, the composition of the phosphate ester compound synthesized can be adjusted even under the same production conditions. That is, the ratio of the phosphate esters P1 to P5 and orthophosphoric acid contained in the phosphate compound (A) can be adjusted.

[0126] The P NMR integral ratios of the phosphate compounds (A) shown in Table 2 were measured by the following method. (Method for measuring P NMR integral ratio) The P NMR integral ratio of the phosphoric acid compound (A) was measured by first pretreating the phosphoric acid compound (A) by adding excess KOH to the compound to adjust the pH to 12 or higher. This pretreatment allows the peaks attributable to phosphate ester P1, phosphate ester P2, phosphate ester P3, phosphate ester P4, phosphate ester P5, orthophosphoric acid, and its salts to be clearly separated in the P-NMR measurement.

[0127] The P nuclear NMR integral ratio was measured using 31P-NMR (product name: MERCURY plus NMR Spectrometer System, 300 MHz, manufactured by VALIAN, the same applies below).

[0128] The solvent used was a mixed solvent of heavy water / tetrahydrofuran = 8 / 2 (volume ratio). Among the obtained signals, the integral value of the single signal appearing between -3 ppm and -7 ppm corresponds to the P atom in P1.

[0129] The sum of the integrals of the doublet signals appearing between -3 ppm and -7 ppm and the doublet signals appearing between -7 ppm and -11 ppm corresponds to the P atoms in P2. The integral of the single signal appearing between -7 ppm and -14 ppm corresponds to the P atom in P3.

[0130] The integral value of the single signal appearing between 3 ppm and 7 ppm corresponds to the P atom in P4. The integral value of the single signal appearing between -1 ppm and 4 ppm corresponds to the P atom in P5.

[0131] The integral value of the signal appearing between 4 ppm and 10 ppm corresponds to the P atom in orthophosphate and its salts. However, if signals are detected in overlapping ranges within the above values, signals from P atoms corresponding to orthophosphoric acid and its salts, phosphate esters P4, P5, P2 (-3 ppm to -7 ppm), P1, P2 (-7 ppm to -11 ppm), and P3 will be detected, in order from the low magnetic field side.

[0132] The value can be calculated by the above-mentioned formula (1), assuming that the total of the P nucleus NMR integral ratios assigned to phosphate ester P1, phosphate ester P2, phosphate ester P3, phosphate ester P4, phosphate ester P5, orthophosphoric acid and its salts is 100%.

[0133] The acid value of the phosphoric acid compound (A) shown in Table 2 was measured by the following method. (Method for measuring acid value) The phosphoric acid compound (A) was dissolved in a mixed solvent of ethanol / xylene = 1 / 2 (volume ratio), set in a potentiometric titrator, and titrated with a 0.1 mol / L potassium hydroxide methanol standard solution. The acid value was calculated using the same formula as used to measure the acid value of the treatment agent described above.

[0134] (pH measurement method) The treatment agent of each example was diluted with water to prepare a 1% by mass aqueous solution, and the pH of the prepared 1% by mass aqueous solution at 25°C was measured in accordance with a conventional method using a known pH measuring device (Horiba, Ltd., tabletop pH meter F-72).

[0135] Details of the alcohol (B) shown in Table 1 are as follows. <Alcohol (B)> B-1: Lauryl alcohol B-2: Octyl alcohol B-3: Stearyl alcohol The details of the fatty acids (C) shown in Table 1 are as follows.

[0136] <Fatty acid (C)> C-1: Lauric acid C-2: Stearic acid Details of the nonionic surfactant (D) shown in Table 1 are as follows.

[0137] <Nonionic surfactant (D)> D-1: Polyoxyethylene (40 mol) triacontyl ether D-2: Polyoxyethylene (50 mol) tetracontyl ether D-3: Pentaglycerin monooctadecanoate D-4: Tetraglycerin monooctadecanoate D-5: Polyoxyethylene (10 mol) octacosyl ether D-6: Polyoxyethylene (20 mol) oleyl ether D-7: Polyoxyethylene (10 moles) hydrogenated castor oil ether D-8: Polyoxyethylene (15 mol) sorbitan monolaurate D-9: Polyoxyethylene (20 mol) sorbitan stearate D-10: Polyoxyethylene (10 moles) coconut fatty acid ester D-11: Polyoxyethylene (15 mol) palm fatty acid ester Details of the other component (E) shown in Table 1 are as follows.

[0138] <Other ingredients (E)> E-1: Lactic acid E-2: Dioctyl sulfosuccinate sodium salt E-3: Dodecylsulfonic acid sodium salt As other components (E), E-4 to E-6 shown in Table 4 were also used.

[0139] [Table 4]

[0140] In Table 4, "Me group" and "n-Bu group" mean methyl group and normal butyl group, respectively. "Si%" means the mass ratio of the portion obtained by excluding alkylene oxide from the mass average molecular weight of the polyether-modified silicone. "EO% (molar ratio)" means the molar ratio of ethylene oxide to alkylene oxide. For example, when the alkylene oxide contains ethylene oxide (hereinafter also referred to as EO) and propylene oxide (hereinafter also referred to as PO), the EO% (molar ratio) can be calculated using the following formula.

[0141] EO% (molar ratio) = (EO moles / (EO moles + PO moles)) x 100 Test Category 2 (Adhesion of nonwoven fabric treatment agents to polyolefin synthetic fibers) Polyolefin-based composite fibers (fineness 2.2 dtex, fiber length 51 mm) with a polyethylene sheath and a polyester core were prepared. A 10% by mass aqueous solution of each treatment agent prepared in Test Section 1 was further diluted with water to a 0.4% by mass aqueous solution, and this was sprayed onto 100 g of the fiber to give a nonvolatile content of 0.40%. After drying for 2 hours in a hot air dryer at 80°C, the fiber was conditioned overnight in an atmosphere at 20°C and 65% RH to obtain treatment-applied polyolefin-based composite fibers.

[0142] Test Section 3 (Making Thermal Bonded Nonwoven Fabric) 100 g of the treatment-applied polyolefin-based composite fiber was conditioned for 24 hours in a temperature-controlled room at 20°C and 65% RH. The treatment-applied polyolefin-based composite fiber after conditioned humidity was passed through a roller carding machine to obtain a fiber weight of 20 g / m. 2 The resulting carded web was subjected to a hot air treatment at 140°C for 10 seconds to obtain a thermal-bonded nonwoven fabric.

[0143] Test category 4 (initial hydrophilicity) The thermal bonded nonwoven fabric obtained in Test Section 3 was conditioned for 24 hours in a thermostatic chamber at 20°C and 65% RH, then placed on a horizontal plate and a 0.4 mL drop of water was dropped on it from a height of 10 mm using a burette. The time required for the drop to be completely absorbed was measured and evaluated according to the following criteria.

[0144] Evaluation criteria for initial hydrophilicity 3 (Good): When it takes less than 3 seconds for water to penetrate 2 (Acceptable): When the time required for water to permeate is 3 seconds or more but less than 6 seconds 1 (Not acceptable): When it takes more than 6 seconds for water to penetrate Test category 5 (durable hydrophilicity) The thermobonded nonwoven fabric obtained in Test Section 3 was cut into 10 cm x 10 cm pieces and conditioned for 24 hours in a thermostatic chamber at 20°C and 65% RH. The conditioned thermobonded nonwoven fabric was placed on top of five stacked filter papers, and a 1 cm inner diameter cylinder with open ends was placed vertically in the center of the fabric. 5 mL of 0.9% saline was poured into the cylinder. The time until the saline solution was completely absorbed into the thermobonded nonwoven fabric was measured. The thermobonded nonwoven fabric was then removed and air-dried at 40°C for 90 minutes. This procedure was repeated twice, and the results were evaluated according to the following criteria starting from the second time.

[0145] ·Evaluation criteria for durable hydrophilicity 3 (Good): When it takes less than 5 seconds for the saline solution to be absorbed 2 (Acceptable): When the time required for saline to be absorbed is between 5 and 10 seconds 1 (Not acceptable): If it takes more than 10 seconds for the saline solution to be absorbed Test category 6 (high temperature and humidity treatment) The polyolefin composite fiber with the treatment agent attached was aged for 48 hours in a constant temperature room at 70°C x 90% RH to obtain a polyolefin composite fiber with the treatment agent attached that had been treated at high temperature and high humidity (hereinafter also referred to as high temperature and high humidity treated fiber) simulating long-term storage. In the present invention, long-term storage means storage for 48 hours or more.

[0146] Test Category 7 (Friction change rate after long-term storage) 20 g of fiber that had undergone high-temperature, high-humidity treatment and 20 g of polyolefin-based composite fiber with a treatment agent attached but not subjected to high-temperature, high-humidity treatment were each conditioned for 24 hours in a constant-temperature chamber at 20°C and 65% RH, and then fed into a miniature carding machine to produce a carded web. The produced carded web was then fed into a miniature drawing frame to obtain a sliver with a grain weight of 3 g / m. The draft force was measured when the sliver was drafted under the two conditions above at a sliver speed of 1 m / min and a draft ratio of 1.5. The friction change rate between the cases with and without high-temperature, high-humidity treatment was calculated using the following formula and evaluated according to the following criteria. The results are shown in the "Friction Change Rate" column of Table 1.

[0147] [Friction change rate] = [Draft force of polyolefin composite fiber with treatment agent attached that has not been treated with high temperature and humidity] / [Draft force of fiber that has been treated with high temperature and humidity] x 100 Evaluation criteria for friction change rate 3 (Good): Friction change rate is less than 5% 2 (Acceptable): When the friction change rate is 5% or more but less than 10% 1 (Not acceptable): When the friction change rate is 10% or more Test category 8 (emulsion stability) Hard water with a hardness of 300 was prepared by dissolving 300 mg of calcium carbonate in 1 L of distilled water. Using the hardness of 300, an aqueous solution of hard water was prepared in which the concentration of each treatment agent in each example was 10% by mass. This aqueous solution was further diluted with hard water to prepare an aqueous solution with a non-volatile content of 0.3% by mass. The aqueous solution was kept at a constant temperature of 20°C for 24 hours, after which the state of the aqueous solution was visually inspected and evaluated according to the following criteria. The results are shown in the "Emulsion Stability" column of Table 1.

[0148] ·Evaluation criteria for emulsion stability 3 (Good): No precipitate or particles 2 (Acceptable): No sediment but particles present 1 (Not acceptable): If there is sediment Test Category 9 (Wet Friction Characteristics) The 10% by mass aqueous solution of the treatment agent prepared in Test Section 1 was diluted with ion-exchanged water to prepare a 0.35% by mass aqueous solution. 80 mL of the prepared 0.35% by mass aqueous solution was placed in a metal tray measuring 60 mm long x 230 mm wide x 20 mm high.

[0149] A rectangular plate-shaped weight measuring 30 mm in length, 90 mm in width, and 45 mm in height, weighing 1 kg, was prepared. A polyester spunbond nonwoven fabric of the same size as the bottom of the weight was attached to the bottom surface using double-sided tape. The weight was placed in the pad containing the 0.35% by mass aqueous liquid, with the bottom surface with the polyester spunbond nonwoven fabric attached facing downwards.

[0150] A tensile test was conducted using a tensile testing machine (Shimadzu Corporation, Autograph Model AGS-X) equipped with a load cell with a maximum load capacity of 50 N, in an atmosphere of 20°C x 60% RH, at a horizontal speed of 100 mm / min.

[0151] The frictional properties between the fiber and metal in a wet state were evaluated using the above method. Specifically, the frictional properties between the fiber and a metal roller in the spinning process and drawing process were evaluated using the above method. The evaluation of the frictional properties was carried out within 12 hours after preparing the 0.35 mass% aqueous solution. When the treatment agent of Comparative Example 1 was used, the friction between the fiber and metal in a wet state became relatively large, so the evaluation was carried out using Comparative Example 1 as the standard and the following evaluation criteria. The results are shown in the "Wet Friction" column of Table 1.

[0152] Evaluation criteria for wet friction characteristics 3 (Good): The M / N ratio, which is the ratio of the friction N measured using the 0.35% by mass aqueous solution of Comparative Example 1 to the friction M measured using the 0.35% by mass aqueous solution of each example, is 0.98 or less. 2 (Acceptable): The above M / N ratio is greater than 0.98 and less than or equal to 0.99. 1 (Not acceptable): If the above M / N ratio is greater than 0.99 Test category 10 (anti-foaming) The 10% by mass aqueous solution of the treatment agent prepared in Test Section 1 was diluted with ion-exchanged water to prepare a 0.25% by mass aqueous solution. 25 g of the prepared aqueous solution was placed in a 100 mL graduated cylinder with a stopper and vigorously shaken 30 times over 30 seconds, allowed to stand for 30 seconds, and then vigorously shaken again 30 times over 30 seconds. After allowing to stand for 5 minutes, the height H1 from the water surface to the top of the foam was measured. Evaluation was based on the following criteria. The results are shown in the "Foam Inhibition" column of Table 1.

[0153] ·Evaluation criteria for foam suppression 3 (Good): H1≦10.0cm 2 (possible): 10.0cm 1 (not allowed): 18.0cm Test Category 11 (Acid Value of Treatment Agent) The acid value of the treatment agent was measured according to JIS K 0070-1992 "3.2 Potentiometric titration method." The solvent used was a mixed solvent of ethanol and xylene. The results are shown in the "Acid value of treatment agent" column in Table 1.

[0154] Test Category 12 (pH of treatment agent) ​​The treatment agent of each example was diluted to prepare a 1% by mass aqueous solution of the treatment agent. The pH of the prepared 1% by mass aqueous solution at 25°C was measured using a known pH meter (tabletop pH meter F-72 manufactured by Horiba, Ltd.).

[0155] As shown in Table 1, the treatment agent of Comparative Example 1 did not contain alcohol (B) and had an acid value outside the range of the present invention, confirming that it had poor anti-foaming properties. The treatment agents of Comparative Examples 2 and 3 did not contain alcohol (B), and the phosphoric acid compound (A) did not contain phosphoric acid ester P3. The integral ratio of phosphoric acid ester P4 was outside the range of the present invention. Furthermore, the acid value was outside the range of the present invention, and it was confirmed that the treatment agents were inferior in emulsion stability, wet friction properties, and foam suppression.

[0156] It was confirmed that the treating agent of Comparative Example 4 had a value calculated by the formula (1) outside the range of the present invention, and was inferior in the rate of change in friction. The treatment agent of Comparative Example 5 did not contain the alcohol (B) and was confirmed to have poor foam suppressing properties.

[0157] The treatment agents of Comparative Examples 6 and 7 did not contain the alcohol (B), and the phosphoric acid compound (A) did not contain the phosphoric acid ester P3. Furthermore, the integral ratio of the phosphoric acid ester P4 was outside the range of the present invention, and it was confirmed that the emulsion stability and anti-foaming properties were poor.

[0158] The treatment agent of Comparative Example 8 had an acid value outside the range of the present invention, and it was confirmed that the treatment agent had poor wet friction properties. In the treatment agent of Comparative Example 9, the number of carbon atoms in the alkyl group of the phosphate esters P3 to P5 contained in the phosphate compound (A) was outside the numerical range of the present invention, and it was confirmed that the treatment agent was inferior in emulsion stability, initial hydrophilicity, and durable hydrophilicity.

[0159] The treatment agent of Comparative Example 10 did not contain alcohol (B), and the integral ratio of the phosphate ester P5 contained in the phosphate compound (A) was outside the range of the present invention. Furthermore, the acid value was outside the range of the present invention, and it was confirmed that the treatment agent was inferior in wet friction properties, foam suppression, and durable hydrophilicity.

[0160] In the treatment agent of Comparative Example 11, the phosphoric acid compound (A) did not contain phosphoric acid ester P3. The integral ratio of phosphoric acid ester P4 was outside the range of the present invention. Furthermore, the acid value was outside the range of the present invention, and it was confirmed that the treatment agent was inferior in emulsion stability, wet friction properties, and foam suppression.

[0161] The treatment agent of Comparative Example 12 had an acid value outside the range of the present invention, and it was confirmed that the treatment agent had poor emulsion stability. On the other hand, the treatment agent of the present invention can improve the friction change rate after long-term storage, emulsion stability, wet friction characteristics, and foam suppression. It can also improve initial hydrophilicity and durable hydrophilicity. Furthermore, nonwoven fabrics containing fibers to which the treatment agent is attached can be suitably used as sanitary materials, etc.

Claims

1. A fiber treatment agent for nonwoven fabrics, comprising the following phosphoric acid compound (A) and the following alcohol (B): In P-nuclear NMR measurement of the fiber treatment agent for nonwoven fabrics after alkaline overneutralization pretreatment, when the total of P-nuclear NMR integral ratios attributable to phosphate ester P1, phosphate ester P2, phosphate ester P3, phosphate ester P4, phosphate ester P5, orthophosphoric acid and salts thereof is taken as 100%, the P-nuclear NMR integral ratio attributable to phosphate ester P4 is 20% or more and 65% or less, the P-nuclear NMR integral ratio attributable to phosphate ester P5 is 20% or more and 45% or less, and the value calculated by the following mathematical formula (1) is 8 or less: the pH of a 1% by mass aqueous dilution of the fiber treatment agent for nonwoven fabric at 25°C is 5.0 or more and 8.0 or less; The fiber treating agent for nonwoven fabrics is characterized in that the acid value per nonvolatile content of the fiber treating agent for nonwoven fabrics is 5 KOH-mg / g or more and less than 60 KOH-mg / g. Phosphate compound (A): A compound containing a phosphate ester P3 represented by the following formula (3), a phosphate ester P4 represented by the following formula (4), a phosphate ester P5 represented by the following formula (5), and orthophosphoric acid, and optionally further containing at least one selected from a phosphate ester P1 represented by the following formula (1) and a phosphate ester P2 represented by the following formula (2). 【number】 (In Chemical Formula 1, M １ , M ２ , M ３ : hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium. 【number】 (In Chemical Formula 2, R １ : an alkyl or alkenyl group having 8 to 12 carbon atoms. M ４ , M ５ : hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium. 【number】 (In Chemical Formula 3, R ２ , R ３ : an alkyl or alkenyl group having 8 to 12 carbon atoms. M ６ : hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium. 【number】 (In Chemical Formula 4, R ４ : an alkyl or alkenyl group having 8 to 12 carbon atoms. M ７ , M ８ : hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium. 【number】 (In Chemical Formula 5, R ５ , R ６ : an alkyl or alkenyl group having 8 to 12 carbon atoms. M ９ : hydrogen atom, alkali metal, alkaline earth metal (1 / 2), organic amine, ammonium, or phosphonium. [Equation 1] Alcohol (B): an aliphatic alcohol having 8 to 18 carbon atoms.

2. 2. The fiber treating agent for nonwoven fabrics according to claim 1, wherein the value obtained by the formula (1) is 3.5 or less.

3. 2. The fiber treatment agent for nonwoven fabrics according to claim 1, wherein the P NMR integral ratio attributable to the phosphate ester P3 is 6.5% or more and 40% or less.

4. The fiber treatment agent for nonwoven fabrics according to claim 1, wherein the sum of the P nucleus NMR integral ratios attributable to the phosphate ester P2 and the phosphate ester P3 is more than 0% and less than 20%.

5. 2. The fiber treatment agent for nonwoven fabrics according to claim 1, wherein the content of the phosphoric acid compound (A) is 85% by mass or more and 99.9% by mass or less, and the content of the alcohol (B) is 0.1% by mass or more and 15% by mass or less, where the content of the phosphoric acid compound (A) and the content of the alcohol (B) are taken as 100% by mass.

6. The fiber treatment agent for nonwoven fabrics according to claim 1, which satisfies at least one of the following two conditions: Condition 1: The alcohol (B) contains two or more kinds of alcohols having different carbon numbers. Condition 2: Contains a fatty acid (C) having 12 to 20 carbon atoms.

7. 2. The fiber treatment agent for nonwoven fabrics according to claim 1, further comprising the following nonionic surfactant (D): Nonionic surfactant (D): At least one selected from a compound in which a total of 5 to 100 moles of alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a monohydric aliphatic alcohol having 22 to 50 carbon atoms, and an ester compound of a polyglycerol having a condensation degree of 3 to 12 and a saturated fatty acid having 12 to 18 carbon atoms.

8. 8. The fiber treatment agent for nonwoven fabrics according to claim 7, wherein the content of the phosphoric acid compound (A), the alcohol (B), and the nonionic surfactant (D) is 100% by mass, the content of the phosphoric acid compound (A) is 20% by mass or more and 80% by mass or less, the content of the alcohol (B) is 0.1% by mass or more and 10% by mass or less, and the content of the nonionic surfactant (D) is 10% by mass or more and 75% by mass or less.

9. 9. An aqueous solution of a fiber treatment agent for nonwoven fabric according to claim 1, wherein the nonvolatile content of the fiber treatment agent for nonwoven fabric is 0.1% by mass or more and 10% by mass or less.

10. A fiber having the fiber treatment agent for nonwoven fabric according to any one of claims 1 to 8 attached thereto.

11. The fiber according to claim 10, wherein the fiber is a polyolefin-based synthetic fiber.

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