Thermoplastic polyester elastomer composition for nonwoven fabric

Abstract

To provide a thermoplastic polyester elastomer composition enabling easy application of nonwoven fabric forming processes including the melt-blown method.SOLUTION: A thermoplastic polyester elastomer composition comprising (A) a thermoplastic polyester elastomer, preferably a polybutylene terephthalate-based elastomer, (B) a metal salt of a hydroxy fatty acid, preferably a zinc salt of a monohydroxy saturated higher fatty acid having 12-30 carbon atoms, and / or (C) a metal salt of a fatty acid, preferably a zinc salt of a monovalent unsaturated higher fatty acid having 12-30 carbon atoms, the elastomer composition optionally further including (D) a softener for non-aromatic rubber.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a thermoplastic polyester elastomer composition suitable as a material for nonwoven fabrics. [Background technology]

[0002] Conventionally, nonwoven fabrics or dressings containing nonwoven fabrics, such as adhesive bandages, have been used as skin dressings for purposes such as absorbing wound exudates and soaking in medicinal solutions. These nonwoven fabrics are required to have elastomeric properties, such as flexibility, stretchability, and elastic recovery, to avoid restricting skin movement, to prevent damage to the skin / wound associated with skin movement, and to maintain wound protection even when the skin moves. Furthermore, these nonwoven fabrics are often formed by the meltblown process to prevent or inhibit the penetration of viruses, bacteria, and other pathogens. Thermoplastic polyester elastomers are promising materials for such nonwoven fabrics because of their excellent elastomeric properties, such as flexibility, stretchability, and elastic recovery. However, thermoplastic polyester elastomers typically have a large molecular weight to exhibit these excellent elastomeric properties, making them difficult to process using the meltblown process. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-057882 [Patent Document 2] Japanese Patent Application Publication No. 02-014059 [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-129363 [Patent Document 4] Japanese Patent Application Publication No. 11-181258 [Patent Document 5] Japanese Patent Application Publication No. 11-323108 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a thermoplastic polyester elastomer composition to which nonwoven fabric forming methods such as the meltblown method can be easily applied. [Means for solving the problem]

[0005] As a result of extensive research, the present inventors have found that the above object can be achieved by using a specific thermoplastic polyester elastomer composition.

[0006] That is, the various aspects of the present invention are as follows. [1]. A thermoplastic polyester elastomer composition comprising: (A) 100 parts by mass of a thermoplastic polyester elastomer; (B) 0.01 to 5 parts by mass of a hydroxy fatty acid metal salt; and (C) 0.01 to 5 parts by mass of a fatty acid metal salt (excluding those corresponding to the above-mentioned component (B) hydroxy fatty acid metal salt). [2]. The thermoplastic polyester elastomer composition according to item [1], further comprising 0.01 to 10 parts by mass of (D) a non-aromatic rubber softener per 100 parts by mass of the thermoplastic polyester elastomer (A). [3]. A thermoplastic polyester elastomer composition for forming nonwoven fabrics by a meltblown method, comprising: 100 parts by mass of (A) a thermoplastic polyester elastomer; and 0.02 to 10 parts by mass of one or more selected from the group consisting of (B) a hydroxy fatty acid metal salt and (C) a fatty acid metal salt (excluding those corresponding to the above-mentioned component (B) hydroxy fatty acid metal salt). [4]. The thermoplastic polyester elastomer composition according to item [3], further comprising 0.01 to 10 parts by mass of (D) a non-aromatic rubber softener per 100 parts by mass of the thermoplastic polyester elastomer (A). [5]. The thermoplastic polyester elastomer composition according to any one of items [1] to [4], wherein the component (B) hydroxy fatty acid metal salt comprises a zinc salt of a monohydroxy saturated higher fatty acid having 12 to 30 carbon atoms. [6]. The thermoplastic polyester elastomer composition according to any one of items [1] to [4], wherein the component (C) fatty acid metal salt comprises a zinc salt of a monounsaturated higher fatty acid having 12 to 30 carbon atoms. [7]. The thermoplastic polyester elastomer composition according to any one of items [1] to [4], wherein the thermoplastic polyester elastomer component (A) contains a polybutylene terephthalate elastomer. [8]. A nonwoven fabric made of the thermoplastic polyester elastomer composition according to any one of items [1] to [4]. [9]. [8] An article comprising the nonwoven fabric described in item [8].

[10] . A method for forming a nonwoven fabric by a melt-blown method using the thermoplastic polyester elastomer composition according to any one of items [1] to [4]. [Effects of the Invention]

[0007] The thermoplastic polyester elastomer composition of the present invention can be easily applied to nonwoven fabric molding methods such as the meltblown method. Nonwoven fabrics made from the thermoplastic polyester elastomer composition of the present invention have excellent elastomeric properties such as flexibility, stretchability, and elastic recovery. Therefore, the thermoplastic polyester elastomer composition of the present invention can be suitably used as a material for nonwoven fabrics, particularly nonwoven fabrics molded by the meltblown method. Nonwoven fabrics made from the thermoplastic polyester elastomer composition of the present invention, particularly nonwoven fabrics molded by the meltblown method, can be suitably used as dressings or components of dressings. DETAILED DESCRIPTION OF THE INVENTION

[0008] In this specification, the term "resin" is used to include a resin mixture containing two or more resins, and a resin composition containing components other than resin.

[0009] In this specification, the term "more than or equal to" in relation to a numerical range means a certain number or more than a certain number. For example, 20% or more means 20% or more than 20%. The term "less than or equal to" in relation to a numerical range means a certain number or less than a certain number. For example, 20% or less means 20% or less than 20%. Furthermore, the symbol "to" in relation to a numerical range means a certain number, more than a certain number and less than another certain number, or another certain number. Here, another certain number is a number greater than the certain number. For example, 10 to 90% means 10%, more than 10% and less than 90%, or 90%. Furthermore, the upper and lower limits of a numerical range can be arbitrarily combined, and embodiments incorporating such combinations can be interpreted. For example, from a statement regarding the numerical range of a certain characteristic such as "usually 10% or more, preferably 20% or more. On the other hand, it is usually 40% or less, preferably 30% or less," or "usually 10 to 40%, preferably 20 to 30%," it can be read that the numerical range of the certain characteristic is 10 to 40%, 20 to 30%, 10 to 30%, or 20 to 40% in one embodiment.

[0010] Other than in the examples, or where otherwise specified, all numerical values ​​used in the specification and claims should be understood to be modified by the term "about." Without attempting to limit the application of the doctrine of equivalents to the claims, each numerical value should be construed in light of the number of significant digits and by applying ordinary rounding techniques.

[0011] In this specification, terms specifying shapes or geometric conditions, such as parallel, orthogonal, and perpendicular, are intended to include not only the strict meanings but also substantially the same states.

[0012] In this specification, when it is explained that "comprises a certain substance," it is to be understood that, in one embodiment, it contains a certain substance, consists of a certain substance, or consists only of a certain substance. For example, from the explanation that "composition A comprises substances a1 and a2," it is to be understood that, in one embodiment, composition A comprises substances a1 and a2, composition A consists of substances a1 and a2, or composition A consists only of substances a1 and a2.

[0013] 1. Thermoplastic polyester elastomer composition: In one embodiment, the thermoplastic polyester elastomer composition of the present invention comprises (A) a thermoplastic polyester elastomer, and one or more selected from the group consisting of (B) a hydroxy fatty acid metal salt and (C) a fatty acid metal salt (excluding those corresponding to the above-mentioned component (B) hydroxy fatty acid metal salt). In another embodiment, the thermoplastic polyester elastomer composition of the present invention comprises (A) a thermoplastic polyester elastomer, (B) a hydroxy fatty acid metal salt, and (C) a fatty acid metal salt. In one embodiment, the thermoplastic polyester elastomer composition of the present invention may further comprise (D) a non-aromatic rubber softener. Each component will be described below.

[0014] (A) Thermoplastic polyester elastomer: The thermoplastic polyester elastomer composition of the present invention contains the component (A) thermoplastic polyester elastomer. The component (A) thermoplastic polyester elastomer is a copolymer of a polycarboxylic acid and a polyhydroxy compound, and has polyester segments and polyester polyol segments. Here, the polyester segments function as hard segments of the component (A) thermoplastic polyester elastomer. The polyester polyol segments function as soft segments of the component (A) thermoplastic polyester elastomer.

[0015] The component (A) thermoplastic polyester elastomer is preferably a copolymer of a polycarboxylic acid and a polyhydroxy compound, and may be a copolymer having an (a1) aromatic polyester segment and an (a2) aliphatic polyester polyol segment. Here, the (a1) aromatic polyester segment serves as a hard segment of the thermoplastic polyester elastomer (A). The (a2) aliphatic polyester polyol segment serves as a soft segment of the thermoplastic polyester elastomer (A).

[0016] The thermoplastic polyester elastomer (A) functions to impart elastomeric properties such as flexibility, stretchability, and elastic recovery.

[0017] The polycarboxylic acid is a compound having two or more carboxyl groups in one molecule, or an ester-forming derivative thereof. Although omitted in the following description, the following embodiment is intended to be interpreted as including an ester-forming derivative of the compound. For example, the term "terephthalic acid" can be interpreted as "terephthalic acid or an ester-forming derivative thereof."

[0018] Examples of the polycarboxylic acid include dicarboxylic acids such as aromatic dicarboxylic acids and aliphatic dicarboxylic acids.

[0019] Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, and naphthalenedicarboxylic acid.

[0020] Examples of the aliphatic dicarboxylic acid include chain aliphatic dicarboxylic acids such as adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, tridecanedicarboxylic acid, tetradecanedicarboxylic acid, pentadecanedicarboxylic acid, hexadecanedicarboxylic acid, octadecanedicarboxylic acid, and eicosanedicarboxylic acid; and alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, dicyclohexanemethane-4,4'-dicarboxylic acid, and norbornanedicarboxylic acid.

[0021] As the polycarboxylic acid, one or more of these can be used.

[0022] The polyhydroxy compound is a compound having two or more hydroxyl groups in one molecule, or an ester-forming derivative thereof. Although omitted in the following description, the following embodiment is intended to be interpreted as including an ester-forming derivative of the compound. For example, the term "ethylene glycol" can be interpreted as "ethylene glycol or an ester-forming derivative thereof."

[0023] Examples of the polyhydric hydroxy compound include dihydric alcohols, dihydroxy compounds such as aromatic dihydroxy compounds, and saturated aliphatic polyethers.

[0024] Examples of the dihydric alcohol include chain dihydric alcohols such as ethylene glycol, diethylene glycol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, and 2-methyl-1,3-propanediol, and cyclic dihydric alcohols such as 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol.

[0025] Examples of the aromatic dihydroxy compound include bisphenol A (2,2-bis(4-hydroxyphenyl)propane), 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-diethylphenyl)propane, 2,2-bis(4-hydroxyphenyl)pentane, 3,3-bis(4-hydroxyphenyl)pentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, and 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane.

[0026] Examples of the saturated aliphatic polyether include polytetramethylene ether glycol, polypropylene glycol, polyethylene glycol, and polymers of one or more of these.

[0027] As the polyvalent hydroxy compound, one or more of these compounds can be used.

[0028] The (a1) aromatic polyester segment is a segment of an aromatic polyester of the aromatic dicarboxylic acid and the dihydroxy compound, and serves as a hard segment of the component (A) thermoplastic polyester elastomer.

[0029] The aromatic dicarboxylic acid used in the (a1) aromatic polyester segment may preferably contain terephthalic acid. The dihydroxy compound used in the (a1) aromatic polyester segment may preferably contain the dihydric alcohol, more preferably a chain dihydric alcohol. The (a1) aromatic polyester segment may contain structural units derived from the aromatic dicarboxylic acid and a comonomer other than the dihydroxy compound, to the extent that they function as hard segments.

[0030] Examples of the (a1) aromatic polyester segment include a polybutylene terephthalate segment and a polyethylene terephthalate segment. The polybutylene terephthalate segment is an aromatic polyester segment of terephthalic acid and 1,4-butanediol. The polyethylene terephthalate segment is an aromatic polyester segment of terephthalic acid and ethylene glycol.

[0031] The polybutylene terephthalate segment may contain a structural unit derived from a comonomer other than terephthalic acid and 1,4-butanediol, to the extent that it functions as a hard segment. Examples of the comonomer that the polybutylene terephthalate segment may contain include the aromatic dicarboxylic acids other than terephthalic acid, such as isophthalic acid, the dicarboxylic acids, such as aliphatic dicarboxylic acids, the dihydric alcohols other than 1,4-butanediol, such as ethylene glycol, and the dihydroxy compounds, such as the aromatic dihydroxy compounds.

[0032] The polyethylene terephthalate segment may contain a structural unit derived from a comonomer other than terephthalic acid and ethylene glycol, to the extent that it functions as a hard segment. Examples of the comonomer that the polyethylene terephthalate segment may contain include the aromatic dicarboxylic acids other than terephthalic acid, such as isophthalic acid, and the dicarboxylic acids, such as the aliphatic dicarboxylic acids, as well as the dihydric alcohols other than ethylene glycol, such as 1,4-butanediol, and the dihydroxy compounds, such as the aromatic dihydroxy compounds.

[0033] When there are two or more aromatic polyester segments (a1), they may have the same structure or different structures.

[0034] The (a2) aliphatic polyester polyol segment functions as a soft segment of the component (A) thermoplastic polyester elastomer. Examples of the (a2) aliphatic polyester polyol segment include aliphatic polyether segments such as the saturated aliphatic polyethers and copolymers of the saturated aliphatic polyethers and the dicarboxylic acids, as well as aliphatic polyester segments such as the aliphatic polyesters of the aliphatic dicarboxylic acids and the dihydric alcohols, and ring-opening polymers of lactones such as ε-caprolactone.

[0035] The dicarboxylic acid that the (a2) aliphatic polyester polyol segment may contain may preferably be an aliphatic dicarboxylic acid such as adipic acid.

[0036] When there are two or more aliphatic polyester polyol segments (a2), they may have the same structure or different structures.

[0037] Examples of the thermoplastic polyester elastomer component (A) include (A1) polybutylene terephthalate elastomers such as a polyester elastomer having the polybutylene terephthalate segment and the aliphatic polyether segment, and a polyester elastomer having the polybutylene terephthalate segment and the aliphatic polyester segment.

[0038] From the viewpoint of chemical resistance, the thermoplastic polyester elastomer (A) may preferably contain the polybutylene terephthalate elastomer (A1).

[0039] From the viewpoint of chemical resistance, the thermoplastic polyester elastomer component (A) may preferably be crystalline. In this case, the melting point of the thermoplastic polyester elastomer component (A) may preferably be 130°C or higher, more preferably 140°C or higher, and even more preferably 150°C or higher. The melting enthalpy of the thermoplastic polyester elastomer component (A) may preferably be 5 J / g or higher, and even more preferably 10 J / g or higher. On the other hand, from the viewpoint of keeping the molding temperature low, the melting point of the thermoplastic polyester elastomer component (A) may preferably be 200°C or lower, more preferably 190°C or lower, and even more preferably 180°C or lower. The melting enthalpy of the thermoplastic polyester elastomer component (A) may preferably be 40 J / g or lower, more preferably 30 J / g or lower, and even more preferably 20 J / g or lower.

[0040] The melting point and melting enthalpy of the thermoplastic polyester elastomer component (A) are calculated from a second melting curve (the melting curve measured during the final heating process) measured using a differential scanning calorimeter (DSC) in accordance with JIS K7121-1987. The second melting curve is measured using a temperature program consisting of holding at 320°C for 5 minutes, cooling to -50°C at a rate of 10°C / min, holding at -50°C for 5 minutes, and then heating to 320°C at a rate of 10°C / min. The melting point is the peak-top temperature of the melting peak that appears in the second melting curve. When two or more melting peaks are observed, the melting point is the peak-top temperature of the melting peak with the greatest peak top height. The melting enthalpy is the sum of the melting enthalpies calculated from the individual melting peaks. Furthermore, "having crystallinity" means that a melting peak is observed in the second melting curve.

[0041] The mass average molecular weight (Mw) of the thermoplastic polyester elastomer (A) as calculated on a polystyrene basis, determined from a differential molecular weight distribution curve (hereinafter sometimes abbreviated as "GPC curve") measured by gel permeation chromatography (hereinafter sometimes abbreviated as "GPC"), is preferably 1.0 × 10 in terms of chemical resistance and tensile properties. 4More preferably, 3.0 × 10 4 More preferably, 7.0 × 10 4 On the other hand, the mass average molecular weight (Mw) is preferably 1.0 × 10 or more from the viewpoint of applying a nonwoven fabric forming method such as a melt-blowing method. 6 Less than 6.0 × 10, more preferably 5 It may be the following:

[0042] The number average molecular weight (Mn) of the thermoplastic polyester elastomer (component A) calculated in terms of polystyrene as determined from the GPC curve is preferably 4.0×10 3 More preferably, 1.2 × 10 4 More preferably, 2.8 × 10 4 On the other hand, the number average molecular weight (Mn) is preferably 4.0 × 10 or more from the viewpoint of applying a nonwoven fabric forming method such as a melt-blowing method. 5 Less than or equal to 2.4 × 10 5 It may be the following:

[0043] GPC measurements of the thermoplastic polyester elastomer (component (A)) were performed using a JASCO high-performance liquid chromatography system (including a degasser, pump, column oven, and refractive index (RI) detector) with two Agilent Technologies PLgel 5μm MIXED-D GPC columns connected in series. 10 mg of resin was dissolved in 1 mL of 1,1,1,3,3,3-hexafluoro-2-propanol, 9 mL of chloroform (containing 50 ppm of the antioxidant BHT (dibutylhydroxytoluene)) was added, and the resulting solution was filtered through a polytetrafluoroethylene membrane filter. The mobile phase was chloroform, with a column temperature of 40°C, a flow rate of 1 mL / min, and a sample injection volume of 100 μL. The elution volume at each retention volume was determined from the amount detected by the RI detector, assuming that the refractive index of the sample was independent of molecular weight. A calibration curve from each retention volume to its polystyrene-equivalent molecular weight can be created using standard polystyrenes. It is important to select the appropriate standard polystyrene so that the retention volume of the sample to be measured is interpolated onto the calibration curve plot. For information on the theory and practice of GPC, refer to reference books such as "Size Exclusion Chromatography: High-Performance Liquid Chromatography of Polymers," published by Kyoritsu Publishing Co., Ltd. (author: Mori Sadao, first edition, first printing, December 10, 1991) and "Synthetic Polymer Chromatography," published by Ohmsha Co., Ltd. (editors: Otani Hajime and Takarazaki Tatsuya, first edition, first printing, July 25, 2013).

[0044] As the thermoplastic polyester elastomer (A) above, one of these may be used alone or a mixture of two or more thereof.

[0045] (B) Hydroxy fatty acid metal salts: In one embodiment, the thermoplastic polyester elastomer composition of the present invention may contain the above-mentioned component (B) hydroxy fatty acid metal salt. The above-mentioned component (B) hydroxy fatty acid metal salt is a salt of a metal and a compound (hydroxy fatty acid) that is a monocarboxylic acid having a carboxy group (-COOH) in the hydrocarbon chain and has one or more hydroxyl groups in the hydrocarbon chain.

[0046] Examples of the hydroxy fatty acid of the hydroxy fatty acid metal salt of component (B) include saturated monohydroxy higher fatty acids such as hydroxycapric acid, hydroxylauric acid, hydroxymyristic acid, hydroxypalmitic acid, hydroxystearic acid, hydroxyarachic acid, and hydroxybehenic acid; and unsaturated monohydroxy higher fatty acids such as ricinoleic acid and hydroxyoctadecenoic acid. Here, the term "higher fatty acid" refers to a fatty acid having 6 or more carbon atoms, preferably 10 or more carbon atoms.

[0047] The hydroxy fatty acid of the component (B) hydroxy fatty acid metal salt may preferably be the monohydroxy saturated higher fatty acid, more preferably a monohydroxy saturated higher fatty acid having 12 to 30 carbon atoms, even more preferably a monohydroxy saturated higher fatty acid having 16 to 22 carbon atoms, and even more preferably 12-hydroxystearic acid.

[0048] Examples of the metal in the component (B) hydroxy fatty acid metal salt include alkali metals such as sodium, lithium, and potassium; alkaline earth metals such as calcium, magnesium, and barium; and zinc. The metal in the component (B) hydroxy fatty acid metal salt may preferably include zinc.

[0049] The component (B) hydroxy fatty acid metal salt may preferably be a zinc salt of the above-mentioned monohydroxy saturated higher fatty acid, more preferably a zinc salt of the above-mentioned monohydroxy saturated higher fatty acid having 12 to 30 carbon atoms, even more preferably a zinc salt of a monohydroxy saturated higher fatty acid having 16 to 22 carbon atoms, and even more preferably zinc 12-hydroxystearate.

[0050] As the component (B) hydroxy fatty acid metal salt, one of these compounds or a mixture of two or more of them can be used.

[0051] The amount of the hydroxy fatty acid metal salt (component (B)) when used will be described. The amount of the hydroxy fatty acid metal salt (component (B)) may vary depending on the molecular weight of the thermoplastic polyester elastomer (component (A)), from the viewpoint of facilitating the application of nonwoven fabric forming methods such as the meltblown method, based on 100 parts by mass of the thermoplastic polyester elastomer (component (A)). The amount of the hydroxy fatty acid metal salt (component (B)) may be typically 0.02 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more, based on the molecular weight of the thermoplastic polyester elastomer (component (A)). On the other hand, the amount of the hydroxy fatty acid metal salt (component (B)) may be typically 10 parts by mass or less, preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 1.5 parts by mass or less, from the viewpoints of bleed-out resistance and elution testing.

[0052] (C) Fatty acid metal salts: In one embodiment, the thermoplastic polyester elastomer composition of the present invention may contain the above-mentioned component (C) fatty acid metal salt. The above-mentioned component (C) fatty acid metal salt is a salt of a metal and a monocarboxylic acid (fatty acid) having a carboxy group (—COOH) in the hydrocarbon chain.

[0053] In this specification, a salt of a metal with a monocarboxylic acid having a carboxy group (-COOH) in the hydrocarbon chain and a compound (hydroxy fatty acid) having one or more hydroxyl groups in the hydrocarbon chain is the above-mentioned component (B) hydroxy fatty acid metal salt. In other words, those having one or more hydroxyl groups in the hydrocarbon chain are excluded from the above-mentioned component (C) fatty acid metal salt.

[0054] Examples of the fatty acid in the component (C) fatty acid metal salt include higher fatty acids such as saturated higher fatty acids and unsaturated higher fatty acids, etc. Here, higher fatty acids refer to fatty acids having 6 or more carbon atoms, preferably 10 or more carbon atoms.

[0055] Examples of the saturated higher fatty acids include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, and melissic acid.

[0056] Examples of the unsaturated higher fatty acids include monounsaturated higher fatty acids such as palmitoleic acid, oleic acid, vaccenic acid, and erucic acid, diunsaturated higher fatty acids such as linoleic acid, and triunsaturated higher fatty acids such as eleostearic acid.

[0057] The fatty acid of the component (C) fatty acid metal salt may preferably be the above-mentioned higher fatty acid, more preferably a monounsaturated higher fatty acid having 12 to 30 carbon atoms, even more preferably a monounsaturated higher fatty acid having 16 to 22 carbon atoms, and even more preferably oleic acid.

[0058] Examples of the metal in the component (C) fatty acid metal salt include alkali metals such as sodium, lithium, and potassium; alkaline earth metals such as calcium, magnesium, and barium; and zinc. The metal in the component (C) fatty acid metal salt may preferably include zinc.

[0059] The above-mentioned component (C) fatty acid metal salt may preferably be a zinc salt of the above-mentioned higher fatty acid, more preferably a zinc salt of a monounsaturated higher fatty acid having 12 to 30 carbon atoms, even more preferably a zinc salt of a monounsaturated higher fatty acid having 16 to 22 carbon atoms, and even more preferably zinc oleate.

[0060] As the component (C), fatty acid metal salt, one of these compounds or a mixture of two or more of them can be used.

[0061] The amount of the fatty acid metal salt (C) used will be described below. The amount of the fatty acid metal salt (C) used, based on 100 parts by mass of the thermoplastic polyester elastomer (A), may vary depending on the molecular weight of the thermoplastic polyester elastomer (A), from the viewpoint of facilitating the application of nonwoven fabric forming methods such as the meltblown method. The amount of the fatty acid metal salt (C) used, based on 100 parts by mass of the thermoplastic polyester elastomer (A), may be typically 0.02 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more. The amount of the fatty acid metal salt (C) used, based on bleed-out resistance and elution testing, may be typically 10 parts by mass or less, preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 1.5 parts by mass or less.

[0062] In one preferred embodiment, the thermoplastic polyester elastomer composition of the present invention may contain the component (B) hydroxy fatty acid metal salt and the component (C) fatty acid metal salt. By incorporating the component (B) hydroxy fatty acid metal salt and the component (C) fatty acid metal salt, even small amounts of these components can be easily used in nonwoven fabric formation processes such as melt-blown fabrication. Consequently, a nonwoven fabric that is favorable in terms of bleed-out resistance and elution tests can be obtained.

[0063] The thermoplastic polyester elastomer composition of the present invention contains the component (B) hydroxy fatty acid metal salt and the component (C) fatty acid metal salt. The amount of the component (B) hydroxy fatty acid metal salt, based on 100 parts by mass of the component (A) thermoplastic polyester elastomer, is typically 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more, depending on the molecular weight of the component (A) thermoplastic polyester elastomer, in order to facilitate the application of nonwoven fabric forming methods such as the meltblown method. On the other hand, the amount of the component (B) hydroxy fatty acid metal salt is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 1.5 parts by mass or less, in terms of bleed-out resistance and elution testing.

[0064] The amount of the fatty acid metal salt of component (C) may be, based on 100 parts by mass of the thermoplastic polyester elastomer of component (A), usually 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more, depending on the molecular weight of the thermoplastic polyester elastomer of component (A), from the viewpoint of facilitating the application of nonwoven fabric molding methods such as the meltblown method. On the other hand, the amount of the fatty acid metal salt of component (C) may be, based on 100 parts by mass of the thermoplastic polyester elastomer of component (A), usually 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more, from the viewpoint of bleed-out resistance and elution testing.

[0065] The sum of the blending amount of the hydroxy fatty acid metal salt of component (B) and the blending amount of the fatty acid metal salt of component (C) is, based on 100 parts by mass of the thermoplastic polyester elastomer of component (A), usually 0.02 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more, depending on the molecular weight of the thermoplastic polyester elastomer of component (A), from the viewpoint of facilitating the application of nonwoven fabric molding methods such as the meltblown method. On the other hand, from the viewpoint of bleed-out resistance and elution testing, it is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, and most preferably 1.5 parts by mass or less.

[0066] In one embodiment, the blending ratio (mass ratio) of the component (B) hydroxy fatty acid metal salt to the component (C) fatty acid metal salt may be preferably 29 / 1 to 1 / 29, more preferably 28 / 2 to 2 / 28, even more preferably 27 / 3 to 3 / 27, and even more preferably 26 / 4 to 4 / 26.

[0067] Without intending to be bound by theory, the reason why the thermoplastic polyester elastomer composition of the present invention can be easily applied to nonwoven fabric molding methods such as the meltblown method is considered as follows. The outlet of a meltblown nozzle is very narrow, with a diameter of approximately 0.1 to 0.3 mm. On the other hand, the thermoplastic polyester elastomer component (A) has a large molecular weight that allows it to exhibit excellent elastomeric properties. Therefore, when melt-extruded from the outlet of a meltblown nozzle, it is subjected to a large load or stress, resulting in swelling. In addition, it is not sufficiently stretched or thinned by hot air. Furthermore, the thermoplastic polyester elastomer component (A) has excellent thermal or melt adhesion to metals. In other words, it has the undesirable property of being prone to molding problems, such as adhesion of molten fibers near the outlet of a meltblown nozzle. Therefore, it is difficult to extrude the thermoplastic polyester elastomer component (A) into thin fibers (molten fibers). On the other hand, in the thermoplastic polyester elastomer composition of the present invention, by including the component (B) hydroxy fatty acid metal salt or the component (C) fatty acid metal salt, both the internal and external lubrication of the component (A) thermoplastic polyester elastomer are enhanced in the molding temperature range. In particular, in embodiments including the component (B) hydroxy fatty acid metal salt and the component (C) fatty acid metal salt, the interaction between the component (B) hydroxy fatty acid metal salt and the component (C) fatty acid metal salt sufficiently enhances both the internal and external lubrication of the component (A) thermoplastic polyester elastomer in the molding temperature range. Therefore, the thermoplastic polyester elastomer composition of the present invention experiences reduced load or stress during melt extrusion from the outlet of a meltblown nozzle, suppressing swelling and allowing for easy extrusion into thin fibers (molten fibers). Furthermore, hot air stretching and diameter reduction are also sufficiently promoted. Furthermore, molding problems such as adhesion of molten fibers near the outlet of a meltblown nozzle are significantly suppressed. Due to these effects, the thermoplastic polyester elastomer composition of the present invention can be easily applied to nonwoven fabric forming methods such as the meltblown method.

[0068] (D) Non-aromatic rubber softeners: In one embodiment, the thermoplastic polyester elastomer composition of the present invention may contain the above-mentioned component (D) non-aromatic rubber softener. By including the above-mentioned component (D) non-aromatic rubber softener, flexibility can be improved. The above-mentioned component (D) non-aromatic rubber softener is a non-aromatic mineral oil (a hydrocarbon compound derived from petroleum, etc.) or synthetic oil (synthetic hydrocarbon compound). Here, non-aromatic means that for mineral oils, they are not classified as aromatic in the classification below (the number of aromatic carbon atoms is less than 30%). For synthetic oils, this means that aromatic monomers are not used.

[0069] Mineral oils used as rubber softeners are mixtures of one or more of paraffin chains, naphthenic rings, and aromatic rings. They are classified as follows: those with 30 to 45% naphthenic ring carbon atoms are called naphthenic; those with 30% or more aromatic carbon atoms are called aromatic; and those that are neither naphthenic nor aromatic and have 50% or more paraffin chain carbon atoms are called paraffinic.

[0070] Examples of the non-aromatic rubber softener of component (D) include paraffinic mineral oils such as linear saturated hydrocarbons, branched saturated hydrocarbons, and derivatives thereof; naphthenic mineral oils; and synthetic oils such as hydrogenated polyisobutylene, polyisobutylene, and polybutene.

[0071] Among these, the non-aromatic rubber softener (D) may preferably contain (D2) paraffinic mineral oil from the viewpoint of suppressing bleed-out. The number of aromatic carbon atoms contained in the paraffinic mineral oil (D2) may be preferably 20% or less, more preferably 10% or less, and even more preferably 0 to 5%.

[0072] As the component (D), the non-aromatic rubber softener, one of these compounds or a mixture of two or more thereof can be used.

[0073] The amount of the non-aromatic rubber softener (Component (D)) is an optional component and is not particularly limited as long as it does not detract from the objectives of the present invention. From the viewpoint of flexibility, the amount of the non-aromatic rubber softener (Component (D)) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, still more preferably 0.3 parts by mass or more, and most preferably 0.5 parts by mass or more, based on 100 parts by mass of the thermoplastic polyester elastomer (Component (A)). On the other hand, from the viewpoints of bleed-out resistance and elution testing, the amount of the non-aromatic rubber softener (Component (D)) is preferably 10 parts by mass or less, more preferably 6 parts by mass or less, even more preferably 4 parts by mass or less, and even more preferably 2 parts by mass or less.

[0074] The thermoplastic polyester elastomer composition of the present invention may further contain optional components other than the above components (A) to (D), as desired, to the extent that it does not contradict the object of the present invention.

[0075] Examples of the optional components include thermoplastic resins or thermoplastic elastomers other than the component (A) thermoplastic polyester elastomer, softeners or plasticizers other than the component (D) non-aromatic rubber softener, and additives, colorants, fillers, flame retardants, etc. other than the component (B) hydroxy fatty acid metal salt and the component (C) fatty acid metal salt.

[0076] Examples of the other thermoplastic resins include thermoplastic styrene elastomers, thermoplastic urethane elastomers, thermoplastic olefin elastomers, thermoplastic polyurethanes, thermoplastic polyamides, thermoplastic polyesters, polyethylene, ethylene-unsaturated carboxylic acid copolymers, ethylene-vinyl acetate copolymers, polypropylene, acrylic thermoplastic resins such as polymethyl methacrylate, and polyvinyl chloride resins such as vinyl chloride homopolymers.

[0077] Examples of the other softeners or plasticizers include esters of polycarboxylic acids such as di(2-ethylhexyl) phthalate with saturated aliphatic alcohols, plasticizers for polyvinyl chloride such as polyester-based plasticizers, and softeners for aromatic rubbers.

[0078] Examples of the other additives include weathering agents such as antioxidants, light stabilizers, and ultraviolet absorbers; antioxidants such as hindered phenol antioxidants, phosphite antioxidants, thioether antioxidants, and amine antioxidants; lubricants such as acid amides, fatty acids, fatty acid esters, waxes, silicone oils, and modified silicone oils; nucleating agents such as aromatic metal phosphates and gelols; antistatic agents such as glycerin fatty acid esters; and mold release agents, processing aids, and antifouling agents.

[0079] Examples of the colorant include inorganic colorants such as titanium dioxide (titania), red iron oxide, ultramarine (ultramarine blue), and carbon black; and organic colorants such as aniline black, quinacridone red, isoindolinone yellow, and phthalocyanine blue.

[0080] Examples of the filler include inorganic fillers such as calcium carbonate, silica (silicon dioxide), talc, mica, clay, hydrotalcite, and zeolite; and organic fillers such as crosslinked acrylic resin particles.

[0081] Examples of the flame retardant include antimony-based flame retardants, halogen-based flame retardants, metal hydroxides, zinc-based flame retardants, organic phosphate ester-based flame retardants, and nitrogen-containing compound-based flame retardants.

[0082] As the optional component, one or more of these may be used.

[0083] The amount of the optional components is not particularly limited as long as it does not contradict the object of the present invention. In one embodiment, the amount of the optional components may be 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, 5 parts by mass or less, 1 part by mass or less, 0.5 parts by mass or less, 0 to 0.5 parts by mass, or about 0.01 to 50 parts by mass, based on 100 parts by mass of the thermoplastic polyester elastomer (A).

[0084] In one embodiment, the thermoplastic polyester elastomer composition of the present invention may not contain any one or more of the optional components described above.

[0085] As used herein, "not containing a certain component" means that the component is not intentionally blended. In the technical field of resin compositions, when the component is intentionally blended, it is typically blended in an amount of 0.01 part by mass or more. Therefore, "not containing a certain component" can also be rephrased as meaning that the content of the component is typically less than 0.01 part by mass, preferably 0.001 part by mass or less, and more preferably 0 to 0.0001 part by mass, based on 100 parts by mass of the thermoplastic polyester elastomer (Component (A)).

[0086] The thermoplastic polyester elastomer composition of the present invention can be obtained by using any melt kneader to charge the above components (A) to (C) and any optional components used as desired into the melt kneader simultaneously or in any order and melt kneading them, preferably at a resin temperature of 200 to 260°C.

[0087] Examples of the melt kneader include batch kneaders such as pressure kneaders and mixers, extrusion kneaders such as single-screw extruders, co-rotating twin-screw extruders, and counter-rotating twin-screw extruders, and calendar roll kneaders. These may be used in any combination.

[0088] The resulting resin composition can be pelletized by any method and then molded into any article by any method, such as hot cutting, strand cutting, or underwater cutting.

[0089] Alternatively, the resulting resin composition may be subjected to molding as it is (without going through a pelletizing step).

[0090] 2. Goods: The article of the present invention comprises the thermoplastic polyester elastomer composition of the present invention. In one typical embodiment, the article of the present invention is a nonwoven fabric made of the thermoplastic polyester elastomer composition of the present invention, or an article comprising the nonwoven fabric as a constituent member. In one preferred embodiment, the article of the present invention is a nonwoven fabric formed by meltblown using the thermoplastic polyester elastomer composition of the present invention, or an article comprising the nonwoven fabric as a constituent member.

[0091] Examples of the articles of the present invention include nonwoven fabrics as dressings; dressings such as adhesive bandages that contain nonwoven fabrics as constituent components; hygiene products such as diapers and surgical masks that contain nonwoven fabrics as constituent components; and filters such as dust bags for vacuum cleaners and dust collectors that contain nonwoven fabrics as constituent components. [Example]

[0092] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0093] Measurement method The following tests (i) to (e) were carried out after conditioning the test specimens in an environment of 23±2°C temperature and 50±4% humidity for 16 hours or more, and then under the same temperature and humidity conditions unless otherwise specified.

[0094] (a) Durometer hardness (Type A): In accordance with JIS K6253-2012, a 6.3 mm thick press sheet made from the elastomer composition was used as a test piece, and the 15-second value of the durometer hardness (Type A) was measured. In the table, the durometer hardness (Type A) is referred to as "A hardness."

[0095] (b) Melt mass flow rate: The melt mass flow rate (unit: g / 10 min) of the elastomer composition was measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190°C and a load of 21.18 N. In the table, the melt mass flow rate is abbreviated as "MFR."

[0096] (C) Average fiber diameter: A photograph of the nonwoven fabric surface was taken using a scanning electron microscope, two diagonal lines were drawn on the photograph, and the width of the fibers intersecting these diagonal lines was calculated as the fiber diameter (unit: μm) based on the magnification. The number average value of 100 of these fibers was calculated as the average fiber diameter (unit: μm).

[0097] (d) Thickness The thickness (unit: mm) of the nonwoven fabric was measured in accordance with Method A of 6.1 Thickness (ISO method) of JIS L1913:2010.

[0098] (e) Weight per unit area The basis weight of the nonwoven fabric (unit: g / m2) is calculated in accordance with JIS L1913:2010 6.2 Mass per unit area (ISO method). 2 ) was measured.

[0099] (f) Tensile strength, elongation, and 100% modulus: The tensile strength (unit: MPa) and elongation (unit: %) of the nonwoven fabric were measured in accordance with 6.3 Tensile strength and elongation (ISO method) of JIS L1913:2010. The stress at 100% elongation was calculated as the 100% modulus (unit: MPa).

[0100] Raw materials used (A) Thermoplastic polyester elastomer: (A-1) "Hytrel 2401 (trade name)," a thermoplastic polyester elastomer having polybutylene terephthalate hard segments and aliphatic polyether soft segments, manufactured by Toray Celanese Co., Ltd., with a melting point of 162°C, a melting enthalpy of 14 J / g, and a mass-average molecular weight (Mw) of 1.0 x 10 5 , number average molecular weight (Mn) 4.1×10 4 .

[0101] (B) Hydroxy fatty acid metal salts: (B-1) Zinc 12-hydroxystearate, CAS number 35674-68-1. (B-2) Magnesium 12-hydroxystearate, CAS number 40277-04-1.

[0102] (C) Fatty acid metal salts: (C-1) Zinc oleate, CAS number 557-07-3. (C-2) Zinc stearate, CAS number 557-05-1.

[0103] (D) Non-aromatic rubber softeners: (D-1) Paraffin oil "Diana Process Oil PW-90 (product name)" from Idemitsu Kosan Co., Ltd.

[0104] (E) Other ingredients: (E-1) A 1:1 (mass ratio) mixture of BASF Japan Ltd.'s hindered phenol-based antioxidant "Irganox 1010 (trade name)" and BASF Japan Ltd.'s phosphite-based antioxidant "Irgafos 168 (trade name)."

[0105] (F) Comparison component: (F-1) Partially saponified montanic acid ester "Licowax OP (trade name)" from Clariant Japan Co., Ltd. (F-2) Emery Oleochemicals' polymer complex ester "Roxiol G-78 (trade name)".

[0106] Example 1 A blend consisting of 100 parts by mass of the above component (A-1), 0.25 parts by mass of the above component (B-1), 0.25 parts by mass of the above component (C-1), 1.0 part by mass of the above component (D-1), and 0.40 parts by mass of the above component (E-1) was melt-kneaded using a co-rotating twin-screw extruder at a die outlet resin temperature of 220°C to obtain an elastomer composition. The above tests (a) and (b) were then carried out. The results are shown in Table 1.

[0107] Next, an attempt was made to mold the obtained elastomer composition into a nonwoven fabric using a meltblown nonwoven fabric manufacturing device "ALM-MB250 (trade name)" manufactured by AIKI Liotech Co., Ltd. The elastomer composition was melt-kneaded at 240°C using a single-screw extruder and sent to a gear pump. 3 The elastomer composition was fed at a flow rate of 1 / min to a meltblown nozzle (0.2 mm diameter nozzles arranged in a row at 0.9 mm intervals) of the meltblown nonwoven fabric manufacturing equipment, and extruded from the nozzle. At the same time, hot air at 290°C was sprayed onto the extruded elastomer composition, and the elastomer composition, which became thin fibers, was collected on a conveyor to obtain a nonwoven fabric. The hot air pressure was 9 KPa, the distance between the meltblown nozzle and the conveyor was 29 cm, and the conveyor speed was 0.59 m / min. Tests (c) to (f) were carried out. The results are shown in Table 1. Since the elongation exceeded 320%, it is indicated as ">320" in the table.

[0108] Examples 2 to 10 An elastomer composition and a nonwoven fabric were obtained in the same manner as in Example 1, except that the formulation was changed as shown in Table 1 or 2. The above tests (a) to (f) were carried out. The results are shown in Table 1 or 2. Note that the elongation was greater than 320% in all cases, and therefore is indicated in the table as ">320".

[0109] Examples 11-14 Except for changing the formulation as shown in Table 2, elastomer compositions were obtained in the same manner as in Example 1. The above tests (a) and (b) were carried out. The results are shown in Table 2. Subsequently, nonwoven fabric molding was attempted in the same manner as in Example 1. However, none of the elastomer compositions of Examples 11 to 14 extruded from the meltblown nozzle formed fine fibers, and no nonwoven fabric could be obtained. Therefore, the above tests (c) to (f) were omitted.

[0110] [Table 1]

[0111] [Table 2]

[0112] It has been found that the thermoplastic polyester elastomer composition of the present invention can be easily formed into nonwoven fabric by the meltblown method. It has also been found that the preferred thermoplastic polyester elastomer composition of the present invention can be easily formed into nonwoven fabric by the meltblown method, even when the sum of the blending amounts of the hydroxy fatty acid metal salt (component (B)) and the fatty acid metal salt (component (C))) is small. It has also been found that nonwoven fabrics made from the thermoplastic polyester elastomer composition of the present invention have excellent flexibility. Furthermore, by comparing the feel of nonwoven fabrics made from the thermoplastic polyester elastomer composition of the present invention with nonwoven fabrics made from polypropylene, it has been determined that the nonwoven fabrics made from the thermoplastic polyester elastomer composition of the present invention also have excellent elastomeric properties such as stretchability and elastic recovery. Therefore, it has been considered that the thermoplastic polyester elastomer composition of the present invention can be suitably used as a material for nonwoven fabrics. Furthermore, the present inventors have considered that the nonwoven fabric made of the thermoplastic polyester elastomer composition of the present invention can be suitably used as a dressing or a dressing containing a nonwoven fabric as a constituent component, such as adhesive bandages; hygiene products containing a nonwoven fabric as a constituent component, such as diapers and surgical masks; and filters containing a nonwoven fabric as a constituent component, such as dust bags for electric vacuum cleaners and dust collectors. [Brief explanation of the drawings]

[0113] [Figure 1] 1 is a scanning electron microscope photograph of the surface of the nonwoven fabric of Example 1.

Claims

1. (A) 100 parts by mass of thermoplastic polyester elastomer, (B) 0.01 to 5 parts by mass of a hydroxy fatty acid metal salt, and (C) A thermoplastic polyester elastomer composition containing 0.01 to 5 parts by mass of a fatty acid metal salt (excluding those corresponding to the above-mentioned component (B) hydroxy fatty acid metal salt).

2. The thermoplastic polyester elastomer composition according to claim 1, further comprising 0.01 to 10 parts by mass of a non-aromatic rubber softener (D) per 100 parts by mass of the thermoplastic polyester elastomer (A).

3. (A) 100 parts by mass of a thermoplastic polyester elastomer, and 0.02 to 10 parts by mass of one or more selected from the group consisting of (B) hydroxy fatty acid metal salts and (C) fatty acid metal salts (excluding those corresponding to the above-mentioned component (B) hydroxy fatty acid metal salts). A thermoplastic polyester elastomer composition for forming a nonwoven fabric by a meltblown method, comprising:

4. The thermoplastic polyester elastomer composition according to claim 3, further comprising (D) a non-aromatic rubber softener in an amount of 0.01 to 10 parts by mass per 100 parts by mass of the thermoplastic polyester elastomer (A).

5. 5. The thermoplastic polyester elastomer composition according to claim 1, wherein the component (B) hydroxy fatty acid metal salt comprises a zinc salt of a monohydroxy saturated higher fatty acid having 12 to 30 carbon atoms.

6. 5. The thermoplastic polyester elastomer composition according to claim 1, wherein the component (C) fatty acid metal salt comprises a zinc salt of a monounsaturated higher fatty acid having 12 to 30 carbon atoms.

7. The thermoplastic polyester elastomer composition according to any one of claims 1 to 4, wherein the thermoplastic polyester elastomer (A) comprises a polybutylene terephthalate-based elastomer.

8. A nonwoven fabric comprising the thermoplastic polyester elastomer composition according to any one of claims 1 to 4.

9. An article comprising the nonwoven fabric of claim 8.

10. A method for forming a nonwoven fabric by a melt-blown method using the thermoplastic polyester elastomer composition according to any one of claims 1 to 4.

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