JP5640164B2 - Nonwoven fabric and fiber treatment agent - Google Patents

Description

  The present invention relates to a nonwoven fabric and a fiber treatment agent.

  The present applicant first heat-treated the core-sheath-type composite fiber having a hydrophilic agent attached to the surface thereof, and changed the hydrophilicity of the fiber, and the hydrophilicity was partially reduced using the technique. The technique which manufactures a nonwoven fabric was proposed (refer patent document 1). The technique of providing a hydrophilic gradient in the thickness direction of the nonwoven fabric is described not only in the same document but also in Patent Documents 2 and 3, for example.

  By the way, what mixed the silicone type compound as a processing agent which processes a fiber is known, for example, in patent document 4, in order to prevent the sticking of the fiber at the time of manufacturing an elastic fiber, highly polymerized polymer The use of an oil agent composed of an organosiloxane and a base oil is described. Patent Document 5 describes the use of an oil containing a highly polymerized polyorganosiloxane for the purpose of maintaining the dryness of the nonwoven fabric surface even after contact with a liquid without inferior high-speed card properties. However, it is not described that the oil agent contains an alkyl sulfate ester salt or an alkyl sulfonate salt.

JP 2010-168715 A Japanese Patent Laying-Open No. 2005-87659 JP 2005-314825 A JP 2003-201678 A JP-A-5-51872

  In Patent Document 1, it is indispensable to use heat-extensible fibers, and other fibers are not assumed, and further improvement in surface liquid residue and the like has been desired. The techniques described in Patent Documents 2 and 3 also have been desired to further improve the liquid residue on the surface.

  The technique of Patent Document 4 is a technique for preventing sticking of elastic fibers, and there is no suggestion that the oil used in the same document is used for other than elastic fibers.

  Therefore, the subject of this invention is providing the nonwoven fabric which can eliminate the fault which the prior art mentioned above has, and the efficient or simple manufacturing method of the nonwoven fabric.

（式中、Ｚはエステル基、アミド基、アミン基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数１〜１２の直鎖又は分岐鎖のアルキル鎖を表わし、Ｒ₁及びＲ₂はそれぞれ独立に、エステル基、アミド基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数２〜１６の直鎖又は分岐鎖のアルキル基を表わし、Ｘは―ＳＯ₃Ｍ、―ＯＳＯ₃Ｍ又は―ＣＯＯＭを表わし、ＭはＨ、Ｎａ、Ｋ、Ｍｇ、Ｃａ又はアンモニウムを表わす。） The present invention is a nonwoven fabric using heat-fusible fibers to which a fiber treatment agent is attached, wherein the fiber treatment agent comprises the following (A) component, (B) component, and (C) component nonwoven fabric. It is to provide.
(A) polyorganosiloxane,
(B) an alkyl phosphate ester,
(C) Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)

（式中、Ｚはエステル基、アミド基、アミン基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数１〜１２の直鎖又は分岐鎖のアルキル鎖を表わし、Ｒ₁及びＲ₂はそれぞれ独立に、エステル基、アミド基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数２〜１６の直鎖又は分岐鎖のアルキル基を表わし、Ｘは―ＳＯ₃Ｍ、―ＯＳＯ₃Ｍ又は―ＣＯＯＭを表わし、ＭはＨ、Ｎａ、Ｋ、Ｍｇ、Ｃａ又はアンモニウムを表わす。） Further, the present invention is a fiber treatment agent comprising the following component (A), component (B) and component (C), wherein the content ratio of the component (A) to the component (C) (the former: The latter is a nonwoven fabric fiber treatment agent in which the mass ratio is 1: 3 to 4: 1 and the component (A) is contained in a proportion of 30% by mass or less with respect to the mass of the fiber treatment agent. Is.
(A) polyorganosiloxane,
(B) an alkyl phosphate ester,
(C) Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)

The nonwoven fabric of the present invention is easily obtained by heat-treating a web or nonwoven fabric containing fibers whose hydrophilicity is lowered by heat, and the hydrophilicity of a desired portion is lowered.
The nonwoven fabric of the present invention has a part in which the hydrophilicity is partially reduced, and can be utilized for various applications by utilizing the characteristics.
According to the nonwoven fabric fiber treatment agent and the nonwoven fabric production method of the present invention, a nonwoven fabric having a portion with reduced hydrophilicity can be efficiently produced.
According to the method for controlling the hydrophilicity of the nonwoven fabric of the present invention, the part to be subjected to heat treatment can be prepared even if the fibers are purposely mixed, made into two layers, or subjected to a hydrophilic treatment in a separate step after forming the nonwoven fabric. The hydrophilicity of the desired part of a nonwoven fabric can be reduced only by changing or controlling the passage of hot air.

  According to the nonwoven fabric of this invention, the liquid residue of a nonwoven fabric can be reduced by controlling the hydrophilic property of a nonwoven fabric. For example, when the nonwoven fabric of the present invention is used as a surface sheet of an absorbent article, the body fluid once absorbed may flow back to the surface side in contact with the skin of the wearer, or the body fluid may flow on the nonwoven fabric surface. Can be prevented. Therefore, when the nonwoven fabric of the present invention is used as, for example, a surface sheet of an absorbent article, the nonwoven fabric satisfies the absorption performance required for the surface sheet, such as reduction of the remaining liquid amount and reduction of the liquid flow amount.

Fig.1 (a) is a perspective view which shows one Embodiment of the nonwoven fabric of this invention, FIG.1 (b) is a partially expanded view of the cross section along the thickness direction of the nonwoven fabric shown to Fig.1 (a). . FIG. 2 is a schematic view showing a process for producing a partially hydrophobized nonwoven fabric using heat hydrophobized fibers. It is a graph which shows the evaluation result of the magnitude | size of the hydrophilic gradient produced by heat processing.

Hereinafter, the present invention will be described based on preferred embodiments thereof.
The nonwoven fabric of the present invention is preferably an air-through nonwoven fabric.
The “air-through nonwoven fabric” referred to in the present invention refers to a nonwoven fabric manufactured through a process of spraying a fluid of 50 ° C. or higher, for example, gas or water vapor, on a web or a nonwoven fabric, and not only a nonwoven fabric manufactured only in this step, It also includes a nonwoven fabric produced by adding this step to a nonwoven fabric produced by another method, or a nonwoven fabric produced by performing some step after this step.
The non-woven fabric of the present invention is a non-woven fabric using heat-sealing fibers to which a fiber treatment agent containing a specific compound is attached, and is preferably an air-through non-woven fabric.

The fiber treatment agent used in the present invention is attached to the surface of the heat-fusible fiber, and increases the hydrophilicity of the fiber surface as compared with that before attaching the fiber treatment agent.
The fiber treatment agent used in the present invention contains a polyorganosiloxane, an alkyl phosphate ester, and an anionic surfactant represented by the following general formula (1). In the fiber to which the fiber treatment agent containing these three components is attached, the polyorganosiloxane promotes the penetration of the anionic surfactant having an alkyl chain into the fiber, so that the hydrophilicity of the fiber surface is lowered by heat treatment. And change. This is because the polysiloxane chain of the polyorganosiloxane and the alkyl chain of the anionic surfactant are incompatible with each other, so the anionic surfactant penetrates into the more familiar fiber when the fiber is heated and melted. It is thought to happen because of this. Among them, the anionic surfactant represented by the general formula (1) has a bulky alkyl group and can penetrate into the fiber so as to entrap the hydrophilic group. Easy to promote penetration into the interior. Thereby, for example, in the step of blowing hot air onto the web, which is one step of the manufacturing process described later, the amount of heat received by the fibers in the web is naturally different between the hot air blowing surface and the opposite surface (net surface). Therefore, the amount of heat received differs between the fiber on the hot air blowing surface and the fiber on the opposite side, and the contact angle value of the fiber also changes between the fiber on the hot air blowing surface and the fiber on the opposite side. It will be. Utilizing this fact, a nonwoven fabric having a hydrophilicity gradient is produced from one surface, which is the first surface when the nonwoven fabric is viewed in plan, toward the other surface, which is the second surface opposite to the first surface. It can be done.
The fiber treatment agent used in the present application contains polyorganosiloxane as the component (A).

[Component (A)]
As the polyorganosiloxane, either a linear one or a cross-linked two-dimensional or three-dimensional network structure can be used, but a substantially linear one is preferable.

Specific examples of suitable polyorganosiloxanes as the component (A) are alkylalkoxysilanes, arylalkoxysilanes, alkylhalosiloxane polymers or cyclic siloxanes, and the alkoxy groups are typically methoxy groups. It is. As the alkyl group, an alkyl group which may have a side chain having 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, particularly 1 to 4 carbon atoms is suitable. Examples of the aryl group include a phenyl group, an alkylphenyl group, and an alkoxyphenyl group. Instead of an alkyl group or an aryl group, a cyclic hydrocarbon group such as a cyclohexyl group or a cyclopentyl group, or an aralkyl group such as a benzyl group may be used.
Further, the polyorganosiloxane referred to in the present invention is a polyorganosiloxane modified with a highly hydrophilic POE chain from the viewpoint of further promoting the penetration of the surfactant and increasing the contact angle of the fiber surface by heating. It is a concept that does not include.

  The most typical polyorganosiloxane preferred for the present invention is polydimethylsiloxane, polydiethylsiloxane, polydipropylsiloxane, etc., with polydimethylsiloxane being particularly preferred.

  The molecular weight of the polyorganosiloxane is preferably a high molecular weight. Specifically, the weight average molecular weight is preferably 100,000 or more, more preferably 150,000 or more, further preferably 200,000 or more, preferably Is 1 million or less, more preferably 800,000 or less, and still more preferably 600,000 or less. Two or more types of polyorganosiloxanes having different molecular weights may be used as the polyorganosiloxane. When two or more kinds of polyorganosiloxanes having different molecular weights are used, one of them has a weight average molecular weight of preferably 100,000 or more, more preferably 150,000 or more, further preferably 200,000 or more, and preferably Is not more than 1 million, more preferably not more than 800,000, still more preferably not more than 600,000, and the other one has a weight average molecular weight of preferably less than 100,000, more preferably not more than 50,000, more preferably 30,000. It is 5,000 or less, more preferably 20,000 or less, preferably 2000 or more, more preferably 3000 or more, and still more preferably 5000 or more. Further, a preferable blending ratio (the former: latter) of the polyorganosiloxane having a weight average molecular weight of 100,000 or more and the polyorganosiloxane having a weight average molecular weight of less than 100,000 is a mass ratio, preferably 1:10 to 4: 1. More preferably, it is 1: 5 to 2: 1.

The weight average molecular weight of the polyorganosiloxane is measured using GPC. The measurement conditions are as follows. The calculated molecular weight is calculated with polystyrene.
Separation column: GMHHR-H + GMHHR-H (cation)
Eluent: L Farmin DM20 / CHCl ₃
Solvent flow rate: 1.0 ml / min
Separation column temperature: 40 ° C

The content of the polyorganosiloxane in the fiber treatment agent is preferably 1% by mass or more, and more preferably 5% by mass or more from the viewpoint of increasing the change in hydrophilicity due to heat treatment. Moreover, 30 mass% or less is preferable from a viewpoint which is easy to absorb a liquid on the nonwoven fabric surface, and 20 mass% or less is still more preferable. For example, the content of the polyorganosiloxane in the fiber treatment agent is preferably 1% by mass or more and 30% by mass or less, and more preferably 5% by mass or more and 20% by mass or less.
Furthermore, when the nonwoven fabric according to the present invention is applied to the absorbent article as a top sheet, the viewpoint of preventing the hydrophilicity on the top side from being excessively lowered, that is, the liquid flow distance described later becomes long, and the excretory liquid is applied to the skin. Also from the viewpoint of preventing the amount of adhesion from increasing, the content of the polyorganosiloxane in the fiber treatment agent is preferably within the above range.

  A commercial item can also be used as polyorganosiloxane as said (A) component. For example, “KF-96H-1 million Cs” manufactured by Shin-Etsu Silicone Co., “SH200 Fluid 1000000 Cs” manufactured by Toray Dow Corning Co., Ltd. KM-903 "or" BY22-060 "manufactured by Toray Dow Corning Co. can be used.

[(B) component]
The alkyl phosphate ester as the component (B) is intended to improve properties such as carding ability of the raw cotton and uniformity of the web, thereby preventing an increase in the productivity of the nonwoven fabric and a reduction in quality. Blended with fiber treatment agent.
Specific examples of the alkyl phosphate used as the component (B) include those having a saturated carbon chain such as stearyl phosphate, myristyl phosphate, lauryl phosphate, palmityl phosphate, oleyl phosphate, Examples include unsaturated carbon chains such as palmitoleyl phosphate and those having side chains in these carbon chains. More preferably, it is a completely or partially neutralized salt of a mono- or dialkyl phosphate ester having 16 to 18 carbon chains. Examples of the alkyl phosphate ester salt include alkali metals such as sodium and potassium, ammonia, and various amines. Alkyl phosphate ester can be used individually by 1 type or in mixture of 2 or more types.

  The blending ratio of the component (B) in the fiber treatment agent is preferably 5% by mass or more, more preferably 10% by mass or more, from the viewpoints of card machine passability and web uniformity, and heat treatment. From the viewpoint of preventing the fiber from being hydrophobized by the polyorganosiloxane resulting from the above, it is preferably 30% by mass or less, more preferably 25% by mass or less.

（式中、Ｚはエステル基、アミド基、アミン基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数１〜１２の直鎖又は分岐鎖のアルキル鎖を表わし、Ｒ₁及びＲ₂はそれぞれ独立に、エステル基、アミド基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数２〜１６の直鎖又は分岐鎖のアルキル基を表わし、Ｘは―ＳＯ₃Ｍ、―ＯＳＯ₃Ｍ又は―ＣＯＯＭを表わし、ＭはＨ、Ｎａ、Ｋ、Ｍｇ、Ｃａ又はアンモニウムを表わす。）
前記（Ｃ）成分は、前記（Ｂ）成分であるアルキルリン酸エステルは含まない成分を指す。また、前記（Ｃ）成分は、一種を単独で又は２種以上を混合して用いることができる。 [Component (C)]
The component (C) is an anionic surfactant represented by the following general formula (1).
Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)
The component (C) refers to a component that does not contain the alkyl phosphate ester that is the component (B). Moreover, the said (C) component can be used individually by 1 type or in mixture of 2 or more types.

Examples of the anionic surfactant in which X in the general formula (1) is —SO ₃ M, that is, the hydrophilic group is a sulfonic acid or a salt thereof, include a dialkylsulfonic acid or a salt thereof. Specific examples of the dialkyl sulfonic acid include dioctadecyl sulfosuccinic acid, didecyl sulfosuccinic acid, ditridecyl sulfosuccinic acid, di-2-ethylhexyl sulfosuccinic acid, and the like, and dicarboxylic acids such as dialkyl sulfosuccinic acid and dialkyl sulfoglutaric acid. Saturated and unsaturated fatty acids such as compounds sulfonated at alpha position, 2-sulfotetradecanoic acid 1-ethyl ester (or amide) sodium salt, 2-sulfohexadecanoic acid 1-ethyl ester (or amide) sodium salt Alpha sulfo fatty acid alkyl esters (or amides) sulfonated at the α-position of esters (or amides), dialkylalkenes obtained by sulfonating internal olefins of hydrocarbon chains and unsaturated fatty acids Or the like can be mentioned sulfonic acid. The number of carbon atoms in each of the two-chain alkyl groups of the dialkyl sulfonic acid is preferably 4 or more and 14 or less, particularly 6 or more and 10 or less.

  Specific examples of the anionic surfactant in which the hydrophilic group is sulfonic acid or a salt thereof include the following anionic surfactants.

Examples of the anionic surfactant in which X in the general formula (1) is —OSO ₃ M, that is, the hydrophilic group is sulfuric acid or a salt thereof, include dialkyl sulfates. Specific examples thereof include 2-ethylhexyl. A compound obtained by sulfating a branched alcohol such as sodium sulfate or 2-hexyldecyl sulfate, or a branched alcohol such as polyoxyethylene 2-hexyldecyl sulfate or polyoxyethylene 2-hexyldecyl sulfate. Hydroxy fatty acid esters (or 12-sulfate stearic acid 1-methyl ester (or amide) 3-sulfate hexanoic acid 1-methyl ester (or amide) or the like And compounds obtained by sulfating amides).

More specific examples of the anionic surfactant in which the hydrophilic group is sulfuric acid or a salt thereof include the following anionic surfactants.

  As the anionic surfactant in which X in the general formula (1) is —COOM, that is, the hydrophilic group is a carboxylic acid or a salt thereof, a dialkylcarboxylic acid can be mentioned, and specific examples thereof include 11-ethoxyhepta. Hydroxy fatty acid chlorides, such as compounds in which the hydroxy moiety of hydroxy fatty acids such as sodium decanecarboxylate and sodium 2-ethoxypentacarboxylate is alkoxylated and the fatty acid moiety is sodiumated, and the amino group of amino acids such as sarcosine and glycine are alkoxylated And compounds obtained by reacting carboxylic acid in the amino acid part with sodium, and compounds obtained by reacting fatty acid chloride with the amino group of arginic acid.

Specific examples of the anionic surfactant in which the hydrophilic group is a carboxylic acid or a salt thereof include the following anionic surfactants.

In this onset bright, as a fiber processing agent, the general formula (1) anionic surfactant and a polyorganosiloxane represented by the by the use of a fiber treatment agent contained, treated with fiber treatment agent heat-sealing The core-sheath type composite fiber becomes a fiber whose hydrophilicity tends to be lowered by heat treatment. The reason for this is that polyorganosiloxane promotes the penetration of an anionic surfactant having two or more alkyl chains into the fiber, so that the hydrophilicity of the fiber surface tends to be lowered by heat treatment. This is because the polysiloxane chain of the polyorganosiloxane and the alkyl chain of the anionic surfactant are incompatible with each other, so that the anionic surfactant penetrates when the fiber is heated and melted into the more familiar fiber. Presumed to happen.

  The blending ratio of the component (C) in the fiber treatment agent is preferably 1% by mass or more, more preferably 5% by mass or more from the viewpoint of increasing the change in hydrophilicity due to heat treatment. When it becomes too high, it is preferably 20% by mass or less, more preferably 13% by mass or less, from the viewpoint of easily holding the liquid and impairing dryness. The blending ratio of the component (C) is preferably 1% by mass or more and 20% by mass or less, and more preferably 5% by mass or more and 13% by mass or less.

The content ratio (the former: latter) of the polyorganosiloxane as the component (A) and the anionic surfactant as the component (C) in the fiber treatment agent of the present invention is a mass ratio, preferably 1: 3-4. : 1, more preferably 1: 2 to 3: 1.
The content ratio (the former: latter) of the polyorganosiloxane of the component (A) and the alkyl phosphate ester of the component (B) in the fiber treatment agent of the present invention is a mass ratio, preferably 1: 5. -10: 1, more preferably 1: 2-3: 1.

The fiber treatment agent used in the present invention may contain other components in addition to the components (A) to (C) described above. As other components to be blended in addition to the components (A) to (C), anionic, cationic, zwitterionic and nonionic surfactants can be used.
Examples of anionic surfactants include alkyl phosphate sodium salt, alkyl ether phosphate sodium salt, dialkyl phosphate sodium salt, dialkyl sulfosuccinate sodium salt, alkylbenzene sulfonate sodium salt, alkyl sulfonate sodium salt, alkyl sulfate sodium salt, secondary Examples include alkyl sulfate sodium salt (all alkyls preferably have 6 to 22 carbon atoms, particularly preferably 8 to 22 carbon atoms). These may use other alkali metal salts such as potassium salts in place of sodium salts.
Examples of the cationic surfactant include alkyl (or alkenyl) trimethyl ammonium halide, dialkyl (or alkenyl) dimethyl ammonium halide, alkyl (or alkenyl) pyridinium halide, and these compounds have 6 or more carbon atoms. Those having 18 or less alkyl groups or alkenyl groups are preferred. Examples of the halogen in the halide compound include chlorine and bromine.

Examples of the zwitterionic surfactant include alkyl (C1-30) dimethylbetaine, alkyl (C1-30) amidoalkyl (C1-4) dimethylbetaine, alkyl (C1-30). ) Betaine-type zwitterionic surfactants such as dihydroxyalkyl (1-30 carbon atoms) betaine, sulfobetaine-type amphoteric surfactants, alanine [alkyl (1-30 carbon atoms) aminopropionic acid type, alkyl ( Amino acid type amphoteric surfactants such as amphoteric surfactants, glycine types such as alkylbetaines [alkyl (carbon number 1 to 30) aminoacetic acid type etc.] amphoteric surfactants, etc. And aminosulfonic acid type amphoteric surfactants such as alkyl (having 1 to 30 carbon atoms) taurine type.
Examples of nonionic surfactants include polyhydric alcohol fatty acid esters such as glycerin fatty acid ester, poly (preferably n = 2 to 10) glycerin fatty acid ester, sorbitan fatty acid ester (all preferably 8 to 8 carbon atoms of fatty acid). 60), polyoxyalkylene (addition mole number 2-20) alkyl (carbon number 8-22) amide, polyoxyalkylene (addition mole number 2-20) alkyl (carbon number 8-22) ether, polyoxyalkylene-modified silicone And amino-modified silicone.

  The fiber treatment agent of the present invention may contain a treatment agent such as an anti-sticking agent such as modified silicone.

[Fiber treated with fiber treatment agent]
The heat-fusible fiber of the present invention is treated with a fiber treating agent, and the above-described fiber treating agent is attached to at least the surface.
The heat-fusible fiber used in the present invention is a fiber constituting the heat-fusible nonwoven fabric. Examples of the heat-fusible fiber include a heat-fusible core-sheath type composite fiber and a non-heat-extensible fiber. Examples thereof include fibers, heat shrink fibers, three-dimensional crimp fibers, latent crimp fibers, and hollow fibers. In the present invention, it is preferable to use a heat-fusible core-sheath composite fiber.
The heat-fusible core-sheath type conjugate fiber of the present invention is a heat-fusible core-sheath type conjugate fiber similar to the heat-fusible core-sheath type conjugate fiber before the fiber treatment agent is attached. . The core-sheath type composite fiber may be a concentric core-sheath type, an eccentric core-sheath type, a side-by-side type, or an irregular shape, and is preferably a concentric core-sheath type.

Examples of the heat-fusible core-sheath composite fiber to which the fiber treatment agent is attached include, for example, “a sheath portion including a polyethylene resin and a core made of a resin component having a higher melting point than the polyethylene resin” described in JP 2010-168715 A A core-sheath type composite fiber having a part (hereinafter, this fiber is referred to as a core-sheath type composite fiber P). Examples of the polyethylene resin constituting the sheath of the core-sheath type composite fiber P include low density polyethylene (LDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), and the like. A high density polyethylene of ~ 0.965 g / cm ³ is preferred. The resin component constituting the sheath portion of the core-sheath type composite fiber P is preferably a polyethylene resin alone, but other resins can also be blended. Other resins to be blended include polypropylene resin, ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl alcohol copolymer (EVOH), and the like. However, as for the resin component which comprises a sheath part, it is preferable that 50 mass% or more in the resin component of a sheath part is especially 70 mass% or more and 100 mass% or less is a polyethylene resin. Further, the polyethylene resin constituting the sheath part of the core-sheath type composite fiber P preferably has a crystallite size of 10 nm or more and 20 nm or less, and more preferably 11.5 nm or more and 18 nm or less.

The sheath part of the core-sheath type composite fiber P plays a role of incorporating the above-described fiber treatment agent into the inside during heat treatment while imparting heat-fusibility to the heat-sealable core-sheath type composite fiber. On the other hand, a core part is a part which provides intensity | strength to a heat-fusible core-sheath-type composite fiber. As the resin component constituting the core part of the core-sheath type composite fiber P, a resin component having a melting point higher than that of the polyethylene resin that is the constituent resin of the sheath part can be used without particular limitation. Examples of the resin component constituting the core include polyolefin resins such as polypropylene (PP) (excluding polyethylene resin), polyester resins such as polyethylene terephthalate (PET), and polybutylene terephthalate (PBT). Furthermore, a polyamide-type polymer, the copolymer of 2 or more types of the resin component mentioned above, etc. can be used. A plurality of types of resins can be blended and used. In this case, the melting point of the core is the melting point of the resin having the highest melting point.
The heat-fusible core-sheath composite fiber to which the fiber treatment agent is attached has a difference in melting point between the resin component constituting the core part and the resin component constituting the sheath part (the former-the latter) at 20 ° C. or higher. It is preferable that the non-woven fabric is easily produced, and is preferably 150 ° C. or lower. The melting point when the resin component constituting the core is a blend of a plurality of types of resins is the melting point of the resin having the highest melting point.

  The heat-fusible core-sheath composite fiber to which the fiber treating agent is attached is preferably a fiber whose length is increased by heating (hereinafter also referred to as a heat-extensible composite fiber). Examples of the heat-extensible fiber include a fiber that spontaneously extends as the crystal state of the resin changes due to heating. The heat-extensible fiber is present in the nonwoven fabric in a state where its length is extended by heating and / or in a state where it can be extended by heating. When heat-extensible fibers are heated, the fiber treatment agent on the surface is easily taken into the interior, and it becomes easy to form a plurality of portions having greatly different hydrophilicity by heat treatment in the fibers and the nonwoven fabric produced using the fibers.

A preferable heat-extensible conjugate fiber has a first resin component that constitutes a core portion and a second resin component that comprises a polyethylene resin and constitutes a sheath portion, and the first resin component is a second resin component. Has a higher melting point. A 1st resin component is a component which expresses the heat | fever extensibility of this fiber, and a 2nd resin component is a component which expresses heat-fusibility.
The melting points of the first resin component and the second resin component were determined by thermal analysis of a finely cut fiber sample (sample weight 2 mg) using a differential scanning calorimeter (DSC6200 manufactured by Seiko Instruments Inc.) at a heating rate of 10 ° C./min. The melting peak temperature of each resin is measured and defined by the melting peak temperature. When the melting point of the second resin component cannot be clearly measured by this method, the resin is defined as “resin having no melting point”. In this case, the temperature at which the second resin component is fused to such an extent that the strength of the fusion point of the fiber can be measured is used as the temperature at which the molecular flow of the second resin component begins, and this is used instead of the melting point.

  The preferred orientation index of the first resin component in the heat-stretchable conjugate fiber is naturally different depending on the resin used. For example, in the case of a polypropylene resin, the orientation index is preferably 60% or less, more preferably 40% or less. More preferably, it is 25% or less. When the first resin component is polyester, the orientation index is preferably 25% or less, more preferably 20% or less, and still more preferably 10% or less. On the other hand, the second resin component preferably has an orientation index of 5% or more, more preferably 15% or more, and still more preferably 30% or more. The orientation index is an index of the degree of orientation of the polymer chain of the resin constituting the fiber. And when the orientation index of a 1st resin component and a 2nd resin component is each said value, a heat | fever extensible composite fiber comes to expand | extend by heating.

  The orientation index of the first resin component and the second resin component is determined by the method described in paragraphs [0027] to [0029] of JP2010-168715A. Moreover, the method in which each resin component in the thermally stretchable conjugate fiber achieves the orientation index as described above is described in paragraphs [0033] to [0036] of JP-A No. 2010-168715.

  The heat stretchable conjugate fiber can be stretched by heat at a temperature lower than the melting point of the first resin component. The heat-extensible conjugate fiber preferably has a thermal elongation rate of 0.5 to 20% at a temperature 10 ° C. higher than the melting point of the second resin component (softening point in the case of a resin having no melting point). Preferably it is 3 to 20%, More preferably, it is 5.0 to 20%. A nonwoven fabric containing fibers having such a thermal elongation rate becomes bulky due to the elongation of the fibers or has a three-dimensional appearance. The thermal elongation rate of the fiber is determined by the method described in paragraphs [0031] to [0032] of JP2010-168715A.

  The ratio (mass ratio, the former: latter) of the first resin component and the second resin component in the heat-extensible conjugate fiber is 10:90 to 90:10, particularly 20:80 to 80:20, especially 50:50 to 70. : 30 is preferable. As the fiber length of the heat-extensible conjugate fiber, one having an appropriate length is used according to the method for producing the nonwoven fabric. For example, when the nonwoven fabric is manufactured by the card method as described later, the fiber length is preferably about 30 to 70 mm.

  The fiber diameter of the heat-extensible composite fiber is appropriately selected according to the specific use of the nonwoven fabric. When using a nonwoven fabric as a constituent member of an absorbent article such as a surface sheet of the absorbent article, it is preferable to use a nonwoven fabric having a thickness of 10 to 35 μm, particularly 15 to 30 μm. In addition, the fiber diameter of the heat-extensible composite fiber is reduced when the fiber diameter is reduced, and the fiber diameter is a fiber diameter when the nonwoven fabric is actually used.

  As the heat-extensible composite fiber, in addition to the above-described heat-extensible composite fiber, Japanese Patent No. 4131852, Japanese Patent Application Laid-Open No. 2005-350836, Japanese Patent Application Laid-Open No. 2007-303035, Japanese Patent Application Laid-Open No. 2007-204899, The fibers described in JP 2007-204901 A and JP 2007-204902 A can also be used.

The heat-fusible fiber may contain titanium oxide.
Titanium oxide preferably has a particle size in the range of, for example, 0.1 μm to 2 μm, and can be spun by containing it in a resin in the fiber spinning step.
By using fibers containing titanium oxide, the nonwoven fabric has increased whiteness and concealment. In particular, an absorbent article using a nonwoven fabric using a fiber containing titanium oxide as a surface material and the like has high concealability of body fluids such as menstrual blood and urine absorbed in the absorbent body, and the visual appearance from the appearance after use A dry feeling can be obtained.
Titanium oxide can be added at any content, but from the viewpoint of enhancing concealability, the amount of titanium oxide to be contained in the heat-fusible fiber is preferably 0.5% by mass with respect to the total mass of the fiber. Above, more preferably 1 mass% or more, from the viewpoint of productivity, fiber strength properties, card process properties in the nonwoven fabric manufacturing process, cut property in the post-processing step, preferably 5 mass% or less, More preferably, it is 4.5 mass% or less.

[Treatment of fiber with fiber treatment agent]
In the heat-fusible core-sheath type composite fiber of the present invention, the hydrophilicity of the surface of the fiber is increased as compared with the case where the fiber treating agent is adhered, as compared with before the adhesion.
The adhesion amount of the fiber treatment agent is preferably 0.1% by mass or more, more preferably, from the viewpoint of increasing the hydrophilicity of the fiber as a proportion of the total mass of the heat-sealable core-sheath composite fiber excluding the fiber treatment agent. It is 0.1-1.5 mass%, More preferably, it is 0.2-1.0 mass%.

  As a method for attaching the fiber treatment agent to the surface of the fiber, various known methods can be employed without any particular limitation. For example, application by spraying, application by slot coater, application by roll transfer, immersion in a hydrophilic oil, and the like can be mentioned. These treatments may be performed on the fibers before being formed into a web, or may be performed after the fibers are formed into a web by various methods. The fiber having the fiber treatment agent attached to the surface thereof is dried at a temperature sufficiently lower than the melting point of the ethylene resin (for example, 120 ° C. or less) by, for example, a hot air blowing dryer.

  The heat-fusible fiber of the present invention is preferably used for the production of sheet materials such as webs and nonwoven fabrics. In addition, a part of the layered body can be formed on the manufactured sheet material. And the hydrophilic property of a desired part can be reduced by heat-processing after the manufacturing process of the sheet material, and manufacture of a sheet material and a laminated body. The decrease in hydrophilicity may decrease the entire hydrophilicity of the sheet material, or may decrease a part of the sheet material. The thickness (fineness) of the fiber is selected in an appropriate range according to the specific application such as a non-woven fabric produced by using the fiber, but from the viewpoint of producing a non-woven fabric that is soft and has a good touch. Is preferably 1.0 to 10.0 dtex, and more preferably 2.0 to 8.0 dtex.

  The non-woven fabric of the present invention may use a mixture of heat-extensible fibers and non-heat-extensible fibers as heat-fusible fibers. The non-heat-extensible fiber is a bicomponent composite fiber that includes a high-melting component and a low-melting component, and the low-melting component is continuously present in the length direction on at least a part of the fiber surface. The form of the composite fiber (non-heat-extensible fiber) includes various forms such as a core-sheath type and a side-by-side type, and any form can be used. The heat-fusible composite fiber is drawn at the raw material stage. The stretching treatment referred to here is a stretching operation with a stretching ratio of about 2 to 6 times. The mixing ratio of the heat-extensible fiber and the non-heat-extensible fiber is a mass ratio, and the former: the latter is preferably 1: 9 to 9: 1, and more preferably 4: 6 to 6: 4. Thereby, it becomes easier to recover the bulk of the nonwoven fabric with hot air, and it is possible to obtain a nonwoven fabric with better touch and dryness than using each fiber alone.

  Thus, the nonwoven fabric which has several parts from which hydrophilicity mutually differs is obtained by heat-processing to the web and nonwoven fabric manufactured using the heat-fusible fiber.

In the heat-fusible fiber of the present invention, the contact angle of water with respect to the fiber taken out from the nonwoven fabric is preferably 90 degrees or less. When the hydrophilicity of the surface is further increased by the fiber treatment agent, it becomes possible to form a plurality of regions having greatly different hydrophilicities on the fiber itself or a nonwoven fabric produced using the fiber. From the same viewpoint, the heat-fusible core-sheath composite fiber taken out from the nonwoven fabric of the present invention has a contact angle with water of preferably 90 degrees or less, more preferably 85 degrees or less, and hydrophilicity. If it is too high, the liquid tends to be held, and therefore it is preferably at least 60 °, more preferably at least 65 °. Moreover, it is preferably 65 to 85 degrees, and more preferably 70 to 80 degrees. Low hydrophilicity is synonymous with an increase in contact angle.
The contact angle of water with the fiber taken out from the nonwoven fabric is measured by the following method. As a measuring device, an automatic contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used. Distilled water is used for contact angle measurement. The amount of liquid discharged from an ink jet type water droplet discharge part (manufactured by Cluster Technology, Inc., pulse injector CTC-25 having a discharge part pore diameter of 25 μm) is set to 20 picoliters, and a water drop is dropped directly above the fiber. The state of dripping is recorded on a high-speed recording device connected to a horizontally installed camera. The recording device is preferably a personal computer incorporating a high-speed capture device from the viewpoint of image analysis or image analysis later. In this measurement, an image is recorded every 17 msec. In the recorded video, the first image of water drops on the fiber taken out from the nonwoven fabric is attached to the attached software FAMAS (software version is 2.6.2, analysis method is droplet method, analysis method is θ / 2 Method, image processing algorithm is non-reflective, image processing image mode is frame, threshold level is 200, and curvature correction is not performed). Calculate the contact angle.
In addition, the sample for measurement (fiber obtained by taking out from a nonwoven fabric) is the fiber located in the corresponding part in the top part P1 of a convex part, the recessed part vicinity part, and back surface (flat surface) P2 shown in FIG.1 (b) from an outermost layer. Cut with a fiber length of 1 mm, place the fiber on a sample table of a contact angle meter and keep it horizontal, and measure two different contact angles for each fiber. In each of the aforementioned parts, N = 5 contact angles are measured to one decimal place, and a value obtained by averaging a total of 10 measured values (rounded to the second decimal place) is defined as each contact angle.

1 (a) and 1 (b) are diagrams showing a nonwoven fabric 10 which is an embodiment of the nonwoven fabric of the present invention. After forming a web from the heat-fusible fiber of the present invention, one of the webs is shown. It was obtained by reducing the hydrophilicity of the part. As a method for obtaining a web from the heat-fusible fiber of the present invention, various known methods such as a card method, an airlaid method, and a spunbond method can be used. As shown in FIG. The method used (card method) is preferred.
As shown in FIG. 2, the nonwoven fabric shown in FIG. 1 (a) and FIG. 1 (b) forms a web 12 by using a card machine 11 using a short fiber aggregate of fibers whose hydrophilicity is lowered by heat as a raw material. The web 12 was introduced into an embossing device 13 having a pair of rolls 14 and 15 to perform embossing, and the web 16 after embossing was heat treated by a hot-air treatment device 17 using an air-through method. Is.
One of the pair of rolls used for the embossing is an embossing roll 14 in which convex portions for embossing in a lattice pattern are formed on the peripheral surface, and the other has a smooth peripheral surface and faces the embossing roll. The flat roll 15 is arranged. Embossing is performed by pressing and compressing the web between the convex portion of the embossing roll 14 and the smooth peripheral surface of the flat roll 15. Thereby, the nonwoven fabric which has the thin part (embossing part) 18 formed by the embossing, and the thick part 19 other than that is obtained.

In one embodiment of producing the nonwoven fabric of the present invention, the temperature applied to the web 12 during embossing when producing the nonwoven fabric 10 in this way is set to the sheath portion of the heat-fusible core-sheath composite fiber. In the subsequent hot air treatment, a temperature not lower than the melting point of the polyethylene resin and not higher than the melting point of the resin component of the core is applied. At the time of this embossing, the air permeability decreases as the compression becomes closer to the embossed portion of the web. On the other hand, the polyethylene resin constituting the embossed portion only needs to be melted by pressure and can be minimized. On the other hand, at the time of hot air treatment, the portion (embossed portion) that has been consolidated by embossing has little or no amount of hot air to pass, and hot air passes through thicker portions other than the embossed portion. , Hydrophilicity decreases.
As a result, the thin portion 18 and / or its peripheral portion formed by embossing becomes a hydrophilic portion, and becomes relatively hydrophobic as it becomes closer to the other thick portion 19, and the thickest portion becomes thicker. A nonwoven fabric in which the vicinity of the portion is a portion exhibiting maximum hydrophobicity is obtained. Moreover, by the said hot air process, melting | fusing of the sheath part of parts other than an embossing part advances, the intersection of a fiber is heat-seal | fused, and a strong nonwoven fabric is obtained.

The nonwoven fabric 10 shown in FIGS. 1 (a) and 1 (b) has a single layer structure. The nonwoven fabric 10 has a concavo-convex surface 10b having one concavo-convex shape, and the other surface is flat or a flat surface 10a having a small degree of concavo-convexity compared to the concavo-convex surface.
The thick portion 19 and the thin portion 18 in the nonwoven fabric 10 form a convex portion 119 and a concave portion 118 on the concave-convex surface 10 b of the nonwoven fabric 10. The concave portion 118 includes a first linear concave portion 118a extending in parallel with each other and a second linear concave portion 118b extending in parallel with each other, and the first linear concave portion 118a and the second linear concave portion 118b. And intersect at a predetermined angle. The convex portion 119 is formed in a rhombus-shaped closed region surrounded by the concave portion 118.

  The top part P1 of the thick part is the top part P1 of the convex part 119 formed on the uneven surface 10b of the nonwoven fabric by the thick part 19. Compared with the top portion P1 of the thick portion 19, the thin portion 18 or its neighboring portion P3 has high hydrophilicity. When liquid enters from the uneven surface 10b side, the liquid is introduced to the flat surface 10a side. It is preferable in terms of easy removal and less liquid residue in the nonwoven fabric 10. Further, it is preferable that the hydrophilicity gradually increases from the top portion P1 of the thick portion 19 toward the thin portion (embossed portion) 18 or its vicinity P3.

  The concavo-convex surface 10b of the nonwoven fabric 10 is directed to the embossing roll 14 side during embossing, and is directed to the side opposite to the net surface (breathable support) when hot air treatment is performed by an air-through method. It is the surface of the side which sprays directly. Therefore, when a heat-extensible conjugate fiber is used as a constituent fiber of the nonwoven fabric, the heat-extensible conjugate fiber extends more greatly on the uneven surface 10b than on the flat surface 10a. Therefore, the fiber diameter in the surface of the flat surface 10a becomes larger than the fiber diameter in the surface of the uneven surface 10b. Further, the hydrophilicity of the thick portion 19 is lower on the uneven surface 10b side than on the flat surface 10a side.

In the manufacturing method of the nonwoven fabric 10, the temperature applied to the web at the time of embossing is from the melting point of the polyethylene resin constituting the sheath portion from the viewpoint of suppressing changes in the hydrophilicity in the embossed portion and / or its vicinity (peripheral portion). It is preferably 20 ° C. or lower and lower than the melting point of the resin component constituting the core. On the other hand, the temperature applied during the hot air treatment is at least 10 ° C. lower than the melting point of the polyethylene resin, in particular, more than the melting point of the polyethylene resin, and more preferably the melting point of the polyethylene resin +5 from the viewpoint of surely causing a change in hydrophilicity. It is preferable that the temperature is at least ° C.
According to the heat-fusible core-sheath-type conjugate fiber of the present invention or a nonwoven fabric produced using the same, a nonwoven fabric having a plurality of portions with greatly different hydrophilicity is produced without requiring a complicated device or a special device. When used as a surface sheet of absorbent articles such as sanitary napkins, panty liners, disposable diapers, etc., the obtained nonwoven fabric has a good touch and is unlikely to cause liquid residue on the surface. Liquid flow hardly occurs and shows good absorption performance.
In addition, in this specification, a surface material and a surface sheet are synonymous.

  The hydrophilicity of the heat-fusible core-sheath composite fiber of the present invention or a web containing the same is lowered by heat treatment. The hydrophilic part and the hydrophilic part in the nonwoven fabric of the present invention need only have a high degree of hydrophilicity in comparison with the part whose hydrophilicity has been lowered by heat treatment. In addition, the hydrophobic part or the hydrophobic part may be a part where the hydrophilicity is lowered before the hydrophilicity is lowered by heat treatment or compared with a part where the hydrophilicity is not lowered. The lowering of the hydrophilicity may be any treatment that lowers the hydrophilicity in comparison with that before the heat treatment. A decrease in hydrophilicity is synonymous with an increase in contact angle. Here, the decrease in hydrophilicity means that the difference in contact angle is 2 degrees or more, preferably 2.5 degrees or more, more preferably 3 degrees or more, and 5 degrees or more. More preferably, it is. Further, it is preferably 10 degrees or less, more preferably 8 degrees or less, and even more preferably 7 degrees or less.

  The nonwoven fabric of the present invention may be three-dimensional by secondary processing after partially lowering the hydrophilicity, and further, additional processing such as performing a hydrophilization treatment on only a part may be appropriately performed. Moreover, the nonwoven fabric of this invention may have a hydrophilicity gradient in one of the thickness direction or the plane direction, and may have a hydrophilicity gradient in the thickness direction and a plane direction.

  The non-woven fabric according to the present invention can be applied to various fields by taking advantage of a hydrophilicity gradient, such as a part being hydrophilic and the other part being hydrophobic or a hydrophilicity-reduced part. For example, an absorbent article used for absorbing liquid discharged from the body, such as sanitary napkins, panty liners, disposable diapers, and incontinence pads, a second sheet (a sheet disposed between the surface sheet and the absorber) , A back sheet, a leak-proof sheet, or a personal wipe sheet, a skin care sheet, or an objective wiper.

The basis weight of the web or nonwoven fabric used for the production of the nonwoven fabric is selected within a suitable range depending on the specific use of the intended nonwoven fabric. The basis weight of the nonwoven fabric finally obtained is preferably 10 to 80 g / m ² , particularly 15 to 60 g / m ² .

When the nonwoven fabric 10 is used as, for example, a surface sheet of an absorbent article, the basis weight is preferably 10 to 80 g / m ² , particularly preferably 15 to 60 g / m ² . When using for the same use, the thickness of the convex part 119 (thick part 19) in the nonwoven fabric 10 is preferably 0.5 to 3 mm, particularly 0.7 to 3 mm in a state after bulk recovery by hot air. On the other hand, the thickness of the recess 118 (thin portion 18) is preferably 0.01 to 0.4, particularly 0.02 to 0.2 mm. The thickness of the recess 118 is not substantially changed before and after the hot air is blown. The thickness of the convex part 119 and the concave part 118 is measured by observing the longitudinal section of the nonwoven fabric 10. First, the nonwoven fabric is cut into a size of 100 mm × 100 mm, and a measurement piece is collected. A plate of 12.5 g (diameter 56.4 mm) is placed on the measurement piece, and a load of 49 Pa is applied. Under this state, the longitudinal cross section of the nonwoven fabric is observed with a microscope (VHX-900, manufactured by Keyence Corporation), and the thickness of the convex portion 119 and the concave portion 118 is measured. In addition, when the convex part (thick part) and the concave part (thin part) are formed in the nonwoven fabric, the “thickness of the nonwoven fabric” refers to the thickness of the convex part (thick part).

The area ratio between the concave portion 118 and the convex portion 119 in the nonwoven fabric 10 is expressed by an embossing rate (an embossed area ratio, that is, a ratio of the total area of the concave portion with respect to the entire nonwoven fabric 10), and affects the bulkiness and strength of the nonwoven fabric 10. give. From these viewpoints, the embossing rate in the nonwoven fabric 10 is preferably 5 to 35%, particularly preferably 10 to 25%. The embossing rate is measured by the following method. First, using a microscope (manufactured by Keyence Co., Ltd., VHX-900), obtain a surface enlargement photograph of the nonwoven fabric 10, adjust the scale to this surface enlargement photograph, measure the dimensions of the embossed part in the entire area T of the measurement part, An embossed area U is calculated.
The embossing rate can be calculated by the formula (U / T) × 100.

An absorbent article used for absorbing liquid discharged from the body typically includes a top sheet, a back sheet, and a liquid-retaining absorbent body interposed between both sheets. As the absorbent body and the back sheet when the nonwoven fabric according to the present invention is used as a top sheet, materials usually used in the technical field can be used without particular limitation.
For example, as the absorbent body, a fiber assembly made of a fiber material such as pulp fiber or a fiber assembly in which an absorbent polymer is held can be coated with a covering sheet such as tissue paper or nonwoven fabric. As the back sheet, a liquid-impermeable or water-repellent sheet such as a thermoplastic resin film or a laminate of the film and a nonwoven fabric can be used. The back sheet may have water vapor permeability. The absorbent article may further include various members according to specific uses of the absorbent article. Such members are known to those skilled in the art. For example, when applying an absorbent article to a disposable diaper or a sanitary napkin, a pair or two or more pairs of three-dimensional guards can be disposed on the left and right sides of the topsheet.

As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to embodiment mentioned above.
For example, when the embossed portion is formed on the nonwoven fabric, the embossed portion forming pattern can be an arbitrary pattern such as a multi-row stripe shape, a dot shape, a checkered shape, or a spiral shape instead of the lattice shape. The shape of each point in the case of a dot shape may be a circle, an ellipse, a triangle, a quadrangle, a hexagon, a heart shape, or an arbitrary shape. Moreover, you may employ | adopt the shape which makes a square or rectangular lattice shape, or a tortoiseshell pattern.
Moreover, in the manufacturing method of the nonwoven fabric shown in FIG. 2, when embossing is performed, an embossing roll and / or a flat roll can be heated, and the nonwoven fabric which the hydrophilic property of the embossed part and / or its periphery fell can also be manufactured. In addition, when the nonwoven fabric of the present invention is used for diapers, napkins, wipers, and other products, heat is applied to a desired portion at any time before production, during production, and after product formation. Thus, the hydrophilicity of some or all of the nonwoven fabrics of the present invention can be lowered, or water repellency can be achieved.

  This invention discloses the following fibers or nonwoven fabrics further regarding embodiment mentioned above.

（式中、Ｚはエステル基、アミド基、アミン基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数１〜１２の直鎖又は分岐鎖のアルキル鎖を表わし、Ｒ₁及びＲ₂はそれぞれ独立に、エステル基、アミド基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数２〜１６の直鎖又は分岐鎖のアルキル基を表わし、Ｘは―ＳＯ₃Ｍ、―ＯＳＯ₃Ｍ又は―ＣＯＯＭを表わし、ＭはＨ、Ｎａ、Ｋ、Ｍｇ、Ｃａ又はアンモニウムを表わす。） <1>
A nonwoven fabric using heat-fusible fibers to which a fiber treatment agent is attached, wherein the fiber treatment agent comprises the following components (A), (B) and (C).
(A) polyorganosiloxane,
(B) an alkyl phosphate ester,
(C) Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)

<2>
The nonwoven fabric according to <1>, wherein the polyorganosiloxane is polydimethylsiloxane.
<3>
The nonwoven fabric according to <1> or <2>, wherein the polyorganosiloxane is contained in a proportion of 1% by mass to 30% by mass with respect to the total mass of the fiber treatment agent.
<4>
<1 in which the polyorganosiloxane is contained in a proportion of 1% by mass or more, preferably 5% by mass or more, and 30% by mass or less, preferably 20% by mass or less, based on the total mass of the fiber treatment agent. The nonwoven fabric according to any one of> to <3>.
<5>
The nonwoven fabric according to any one of <1> to <4>, wherein the polyorganosiloxane has a weight average molecular weight of 100,000 or more.
<6>
The polydimethylsiloxane is composed of two or more types of polydimethylsiloxanes, and one type has a weight average molecular weight of preferably 100,000 or more, more preferably 150,000 or more, further preferably 200,000 or more, and preferably Is not more than 1 million, more preferably not more than 800,000, still more preferably not more than 600,000, and the other one has a weight average molecular weight of preferably less than 100,000, more preferably not more than 50,000, more preferably 30,000. The nonwoven fabric according to any one of <1> to <4>, which is 5,000 or less, more preferably 20,000 or less, preferably 2,000 or more, more preferably 3,000 or more, and even more preferably 5,000 or more. .
<7>)
The blending ratio (the former: latter) of the polyorganosiloxane having a weight average molecular weight of 100,000 or more and the polyorganosiloxane having a weight average molecular weight of less than 100,000 is 1:10 to 4: 1, preferably 1: The nonwoven fabric according to <6>, which is 5 to 2: 1.
<8>
In any one of the above items <1> to <7>, the alkyl phosphate used as the component (B) is a completely neutralized or partially neutralized salt of a mono- or dialkyl phosphate having a carbon chain of 16 to 18 The nonwoven fabric described.
<9>
<1> to <8, wherein the blending ratio of the component (B) in the fiber treatment agent is 5% by mass or more, preferably 10% by mass or more, and 30% by mass or less, preferably 25% by mass or less. > Any one of>.

（式中、Ｚはエステル基、アミド基、アミン基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数１〜１２の直鎖又は分岐鎖のアルキル鎖を表わし、Ｒ₁及びＲ₂はそれぞれ独立に、エステル基、アミド基、ポリオキシアルキレン基、エーテル基若しくは２重結合を含んでいてもよい、炭素数２〜１６の直鎖又は分岐鎖のアルキル基を表わし、Ｘは―ＳＯ₃Ｍ、―ＯＳＯ₃Ｍ又は―ＣＯＯＭを表わし、ＭはＨ、Ｎａ、Ｋ、Ｍｇ、Ｃａ又はアンモニウムを表わす。）
＜２８＞
前記ポリオルガノシロキサンが、ポリジメチルシロキサンである前記＜２７＞記載の不織布用繊維処理剤。
＜２９＞
前記ポリジメチルシロキサンが２種類以上のポリジメチルシロキサンから構成され、そのうちの一種類が重量平均分子量１０万以上のポリジメチルシロキサン、他の一種類が重量平均分子量１０万未満のポリジメチルシロキサンから構成される前記＜２７＞又は＜２８＞記載の不織布用繊維処理剤。
＜３０＞
重量平均分子量が１０万以上のポリオルガノシロキサンと重量平均分子量が１０万未満のポリオルガノシロキサンとの好ましい配合比率（前者：後者）は、質量比で、好ましくは１：１０〜４：１、より好ましくは１：５〜２：１である前記＜２９＞記載の不織布用繊維処理剤。
＜３１＞
前記（Ｂ）成分として用いるアルキルリン酸エステルが、炭素鎖が１６〜１８のモノ又はジアルキルリン酸エステルの完全中和または部分中和塩である前記＜２７＞〜＜３０＞の何れか１に記載の不織布用繊維処理剤。
＜３２＞
前記繊維処理剤中の前記（Ｂ）成分の配合割合は、５質量％以上、好ましくは１０質量％以上であり、３０質量％以下、好ましくは２５質量％以下である前記＜２７＞〜＜３１＞の何れか１に記載の不織布用繊維処理剤。
＜３３＞
前記（Ｃ）成分が、ジアルキルスルホン酸又はその塩である、前記＜２７＞〜＜３２＞の何れか１に記載の不織布用繊維処理剤。
＜３４＞
前記ジアルキルスルホン酸の２鎖のアルキル基それぞれの炭素数は、４〜１４個、特に、６〜１０個であることが好ましい前記＜３３＞記載の不織布用繊維処理剤。
＜３５＞
前記繊維処理剤中の前記（Ｃ）成分の配合割合は、１質量％以上、好ましくは５質量％以上であり、また、２０質量％以下、好ましくは１３質量％以下である前記＜２７＞〜＜３４＞の何れか１に記載の不織布用繊維処理剤。
＜３６＞
前記（Ａ）成分と前記（Ｃ）成分との含有比率（前者：後者）が、質量比で１：３〜４：１である前記＜２７＞〜＜３５＞の何れか１に記載の不織布用繊維処理剤。
＜３７＞
前記繊維処理剤における前記（Ａ）成分のポリオルガノシロキサンと、前記（Ｃ）成分のアニオン界面活性剤との含有比率は、質量比で、好ましくは１：３〜４：１、より好ましくは１：２〜３：１である前記＜２７＞〜＜３６＞の何れか１に記載の不織布用繊維処理剤。
＜３８＞
前記繊維処理剤における前記（Ａ）成分のポリオルガノシロキサンと、前記（Ｂ）成分のアルキルリン酸エステルとの含有比率は、質量比で、１：４〜３：１、好ましくは１：２〜２：１である前記＜２７＞〜＜３７＞の何れか１に記載の不織布用繊維処理剤。
＜３９＞
前記＜２７＞〜＜３８＞の何れか１に記載の繊維処理剤が付着した熱融着性繊維。
＜４０＞
前記繊維処理剤の付着量は、該繊維処理剤を除く熱融着性繊維の全質量に対する割合が、０．１質量％以上、好ましくは０．１〜１．５質量％であり、より好ましくは０．２〜１．０質量％である前記＜３９＞記載の熱融着性繊維。
＜４１＞
水に対する接触角が、９０度以下、好ましくは８５度以下であり、６０度以上、好ましくは６５度以上であり、また、６５〜８５度であり、好ましくは７０〜８０度である前記＜３９＞又は＜４０＞記載の熱融着性繊維。
＜４２＞
前記熱融着性繊維が、熱伸長性繊維である前記＜３９＞〜＜４１＞の何れか１に記載の熱融着性繊維。
＜４３＞
前記熱伸長性繊維は、芯部を構成する第１樹脂成分と、鞘部を構成する第２樹脂成分とを有する熱伸長性複合繊維であり、該熱伸長性複合繊維は、第２樹脂成分の融点（融点を持たない樹脂の場合は軟化点）より１０℃高い温度での熱伸長率が０．５〜２０％であり、好ましくは３〜２０％、より好ましくは５．０〜２０％である前記＜３９＞〜＜４２＞の何れか１に記載の熱融着性繊維。
＜４４＞
前記熱融着性繊維は、酸化チタンを熱融着性繊維の全質量に対して０．５質量％以上５質量％以下の割合で含んでいる、前記＜３９＞〜＜４３＞の何れか１に記載の熱融着性繊維。
＜４５＞
前記＜４０＞〜＜４４＞の何れか１に記載の熱融着性繊維を用いた不織布。
＜４６＞
前記熱融着性繊維として、前記熱伸長性繊維と非熱伸長性繊維とが混綿されている前記＜４５＞記載の不織布。
＜４７＞
エアスルー不織布である、前記＜４５＞又は＜４６＞記載の不織布。
＜４８＞
前記＜２７＞〜＜３８＞の何れか１に記載の繊維処理剤を付着させた熱融着性繊維を含むウエブ又は不織布に、熱処理を施し、該ウエブ又は該不織布の一部の親水性を低下させた不織布を得る、不織布の製造方法。
＜４９＞
前記＜２７＞〜＜３８＞の何れか１に記載の繊維処理剤を付着させた熱融着性繊維を含むウエブ又は不織布に、熱処理を施し、該ウエブ又は該不織布の一部の親水性を低下させる、不織布の親水性の制御方法。 <10>
The nonwoven fabric according to any one of <1> to <9>, wherein the component (C) is a dialkylsulfonic acid or a salt thereof.
<11>
The non-woven fabric according to <10>, wherein each of the two-chain alkyl groups of the dialkylsulfonic acid has 4 to 14 carbon atoms, particularly 6 to 10 carbon atoms.
<12>
The blending ratio of the component (C) in the fiber treatment agent is 1% by mass or more, preferably 5% by mass or more, and 20% by mass or less, preferably 13% by mass or less. The nonwoven fabric according to any one of <11>.
<13>
The nonwoven fabric according to any one of <1> to <12>, wherein the content ratio (the former: the latter) of the component (A) and the component (C) is 1: 3 to 4: 1 by mass ratio. .
<14>
The content ratio of the polyorganosiloxane of the component (A) and the anionic surfactant of the component (C) in the fiber treatment agent is 1: 3 to 4: 1, preferably 1: 2 by mass ratio. The nonwoven fabric according to any one of <1> to <13>, which is 3: 1.
<15>
The content ratio of the polyorganosiloxane of the component (A) and the alkyl phosphate ester of the component (B) in the fiber treatment agent is 1: 5 to 10: 1, preferably 1: 2 by mass ratio. The nonwoven fabric according to any one of <1> to <14>, which is 3: 1.
<16>
Any one of <1> to <15>, which has a first surface of the nonwoven fabric and a second surface opposite to the first surface, and the hydrophilicity increases from the first surface side to the second surface side. The nonwoven fabric according to 1.
<17>
The nonwoven fabric according to any one of <1> to <16>, wherein the nonwoven fabric has a concavo-convex shape, and the hydrophilicity increases from a top portion to a bottom portion of the convex portion.
<18>
The difference between the contact angle of the top of the convex part and the contact angle of the bottom is preferably 2.5 degrees or more, more preferably 3 degrees or more, and even more preferably 5 degrees or more, Moreover, it is preferable that it is 10 degrees or less, it is more preferable that it is 8 degrees or less, and it is still more preferable that it is 7 degrees or less. The nonwoven fabric as described in said <17>.
<19>
It has a thin part formed by embossing and a thick part other than that, the thin part or its vicinity is hydrophilic, and the top part of the thick part is the thickness The non-woven fabric according to any one of <1> to <18>, wherein the hydrophilicity is lower than that of the thin portion or the vicinity thereof.
<20>
The nonwoven fabric according to any one of <1> to <19>, wherein the heat-fusible fiber is a heat-extensible fiber whose length is extended by heat.
<21>
The heat stretchable fiber is a heat stretchable conjugate fiber having a first resin component constituting a core portion and a second resin component constituting a sheath portion, and the heat stretchable conjugate fiber is a second resin component. The thermal elongation at a temperature 10 ° C. higher than the melting point (softening point in the case of a resin having no melting point) is 0.5 to 20%, preferably 3 to 20%, more preferably 5.0 to 20%. The nonwoven fabric according to any one of <1> to <20>, wherein
<22>
The amount of the fiber treatment agent attached to the heat-fusible fiber is such that the proportion of the heat-fusible fiber excluding the fiber treatment agent is 0.1% by mass or more, preferably 0.1 to 1. The nonwoven fabric according to any one of <1> to <21>, which is 5% by mass, more preferably 0.2 to 1.0% by mass.
<23>
Any of the above <1> to <22>, wherein the heat-fusible fiber contains titanium oxide in a ratio of 0.5 mass% to 5 mass% with respect to the total mass of the heat-fusible fiber. The nonwoven fabric according to 1.
<24>
The nonwoven fabric according to any one of <1> to <23>, which is an air-through nonwoven fabric.
<25>
An absorbent article using the nonwoven fabric according to any one of <1> to <24>.
<26>
The absorbent article according to <25>, which is a sanitary napkin.
<27>
A fiber treatment agent for nonwoven fabric containing the following component (A), component (B) and component (C), wherein the content ratio of the component (A) to the component (C) (the former: the latter) is mass. The fiber treatment agent for nonwoven fabrics which is 1: 3-4: 1 by ratio, and (A) component is contained in the ratio of 1 mass% or more and 30 mass% or less with respect to the mass of a fiber treatment agent.
(A) polyorganosiloxane,
(B) an alkyl phosphate ester,
(C) Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)
<28>
The fiber treatment agent for nonwoven fabrics according to <27>, wherein the polyorganosiloxane is polydimethylsiloxane.
<29>
The polydimethylsiloxane is composed of two or more types of polydimethylsiloxane, one of which is composed of polydimethylsiloxane having a weight average molecular weight of 100,000 or more, and the other is composed of polydimethylsiloxane having a weight average molecular weight of less than 100,000. <27> or <28> The fiber treatment agent for nonwoven fabrics described in the above.
<30>
A preferable blending ratio (the former: latter) of the polyorganosiloxane having a weight average molecular weight of 100,000 or more and the polyorganosiloxane having a weight average molecular weight of less than 100,000 is a mass ratio, preferably 1:10 to 4: 1. The fiber treatment agent for nonwoven fabrics according to <29>, preferably 1: 5 to 2: 1.
<31>
Any one of the above <27> to <30>, wherein the alkyl phosphate used as the component (B) is a completely neutralized or partially neutralized salt of a mono- or dialkyl phosphate having a carbon chain of 16 to 18 The fiber treatment agent for nonwoven fabrics as described.
<32>
<27>-<31 which the mixture ratio of the said (B) component in the said fiber processing agent is 5 mass% or more, Preferably it is 10 mass% or more, 30 mass% or less, Preferably it is 25 mass% or less. > The fiber processing agent for nonwoven fabrics of any one of>.
<33>
The fiber treatment agent for nonwoven fabric according to any one of <27> to <32>, wherein the component (C) is a dialkylsulfonic acid or a salt thereof.
<34>
The fiber treatment agent for nonwoven fabric according to <33>, wherein the carbon number of each of the two-chain alkyl groups of the dialkylsulfonic acid is preferably 4 to 14, particularly 6 to 10.
<35>
The blending ratio of the component (C) in the fiber treatment agent is 1% by mass or more, preferably 5% by mass or more, and 20% by mass or less, preferably 13% by mass or less. The fiber treatment agent for nonwoven fabrics according to any one of <34>.
<36>
The non-woven fabric according to any one of <27> to <35>, wherein the content ratio (the former: the latter) of the component (A) and the component (C) is 1: 3 to 4: 1 by mass ratio. Fiber treatment agent.
<37>
The content ratio of the polyorganosiloxane of the component (A) and the anionic surfactant of the component (C) in the fiber treatment agent is a mass ratio, preferably 1: 3 to 4: 1, more preferably 1. : The fiber treatment agent for nonwoven fabrics of any one of said <27>-<36> which is 2-3: 1.
<38>
The content ratio of the polyorganosiloxane as the component (A) and the alkyl phosphate ester as the component (B) in the fiber treatment agent is 1: 4 to 3: 1, preferably 1: 2 by mass ratio. The fiber treatment agent for nonwoven fabrics according to any one of <27> to <37>, which is 2: 1.
<39>
A heat-fusible fiber to which the fiber treatment agent according to any one of <27> to <38> is attached.
<40>
The adhesion amount of the fiber treatment agent is such that the ratio with respect to the total mass of the heat-fusible fiber excluding the fiber treatment agent is 0.1% by mass or more, preferably 0.1 to 1.5% by mass, and more preferably. Is 0.2 to 1.0% by mass of the heat-fusible fiber according to <39>.
<41>
<39, wherein the contact angle with respect to water is 90 degrees or less, preferably 85 degrees or less, 60 degrees or more, preferably 65 degrees or more, 65 to 85 degrees, preferably 70 to 80 degrees. > Or <40>.
<42>
The heat-fusible fiber according to any one of <39> to <41>, wherein the heat-fusible fiber is a heat-extensible fiber.
<43>
The heat stretchable fiber is a heat stretchable conjugate fiber having a first resin component constituting a core portion and a second resin component constituting a sheath portion, and the heat stretchable conjugate fiber is a second resin component. The thermal elongation at a temperature 10 ° C. higher than the melting point (softening point in the case of a resin having no melting point) is 0.5 to 20%, preferably 3 to 20%, more preferably 5.0 to 20%. The heat-fusible fiber according to any one of the above <39> to <42>.
<44>
Any of the above <39> to <43>, wherein the heat-fusible fiber contains titanium oxide in a ratio of 0.5 mass% to 5 mass% with respect to the total mass of the heat-fusible fiber. The heat-fusible fiber according to 1.
<45>
A nonwoven fabric using the heat-fusible fiber according to any one of <40> to <44>.
<46>
The non-woven fabric according to <45>, wherein the heat-extensible fiber and the non-heat-extensible fiber are mixed as the heat-fusible fiber.
<47>
The non-woven fabric according to <45> or <46>, which is an air-through non-woven fabric.
<48>
A heat treatment is applied to the web or nonwoven fabric containing the heat-fusible fiber to which the fiber treatment agent according to any one of <27> to <38> is attached, and the hydrophilicity of a part of the web or the nonwoven fabric is imparted. A method for producing a nonwoven fabric, wherein a reduced nonwoven fabric is obtained.
<49>
A heat treatment is applied to the web or nonwoven fabric containing the heat-fusible fiber to which the fiber treatment agent according to any one of <27> to <38> is attached, and the hydrophilicity of a part of the web or the nonwoven fabric is imparted. A method for controlling the hydrophilicity of a nonwoven fabric to be lowered.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.

[Example 1]
(1) Manufacture of fiber whose hydrophilicity is lowered by heat A heat-fusible core-sheath type composite fiber having a heat-extensible heat-fusible fiber, whose core part is made of polypropylene resin and whose sheath part is made of polyethylene resin is described below. It was immersed in the fiber treatment agent (oil agent) A of the composition. After the immersion, drying was performed to obtain a heat-fusible core-sheath composite fiber to which a fiber treatment agent was adhered. The amount of the oil agent attached to the fiber was 0.39% by mass.

(Composition of fiber treatment agent A)
Polyorganosiloxane (component (A), silicone “KM-903” manufactured by Shin-Etsu Silicone): 8.3% by mass
(Composition of silicone “KM-903”)
-Polydimethylsiloxane having a weight average molecular weight of about 500,000: 18% by mass
-Polydimethylsiloxane having a weight average molecular weight of about 20,000: 42% by mass
・ Dispersant: 5% by mass
・ Water: 35% by mass
Alkyl phosphate potassium salt [the component (B), manufactured by Kao Corporation, neutralized potassium hydroxide of gripper 4131]: 22.9% by mass
Dialkylsulfosuccinate sodium salt [component (C), manufactured by Kao Corporation, Perex OT-P]: 9.2% by mass
Alkyl (stearyl) betaine [components other than the above (A) to (C), manufactured by Kao Corporation, Amphitol 86B]: 13.8% by mass
Polyoxyethylene (added mole number: 2) Stearylamide [components other than the above (A) to (C), manufactured by Kawaken Fine Chemicals, Amizole SDE]: 27.5% by mass
Polyoxyethylene, polyoxypropylene, modified silicone [components other than the above (A) to (C), manufactured by Shin-Etsu Chemical Co., Ltd., X-22-4515]: 18.3 mass%

  In Table 1, the blending amount of component (A) is the blending amount of silicone alone in the composition of “KM-903” described above, and is not the blending amount of “KM-903” as a whole. That is, the blending ratio of each component of the fiber treatment agent shown in Table 1 is a value calculated by excluding the dispersant and water in KM-903.

(2) Manufacture of nonwoven fabric Using the obtained fiber, the nonwoven fabric was manufactured by the method shown in FIG. 2 without using a non-heat-extensible fiber. A specific manufacturing method is as follows. First, the web formed using the card machine was embossed. The embossing was performed such that a grid-like embossed part was formed and the area ratio of the embossed part (compressed part) was 22%. The embossing processing temperature was 110 ° C. Next, air-through processing was performed. In the air-through process, heat treatment was performed once by blowing hot air from the embossed surface side in the embossing process. The heat treatment temperature for air-through processing was 136 ° C.
As shown in FIG. 1, the obtained non-woven fabric has a thin portion (embossed portion) 18 and a thick portion 19 other than that, and one surface has a convex portion 119 and a concave portion 118 and has a large undulation. The uneven surface 10b and the other surface were almost flat surfaces 10a.

[Example 2]
A nonwoven fabric of Example 2 was obtained in the same manner as in Example 1 except that the blending ratio of each component of the fiber treatment agent A (oil agent) was changed to the ratio shown in Table 1.
Example 3
A nonwoven fabric of Example 3 was obtained in the same manner as in Example 1 except that the blending ratio of each component of the fiber treatment agent A (oil agent) was changed to the ratio shown in Table 1.
Example 4
A nonwoven fabric of Example 4 was obtained in the same manner as in Example 1 except that the blending ratio of each component of the fiber treatment agent A (oil agent) was changed to the ratio shown in Table 1.

Example 5
Example in which only a non-heat-extensible fiber having a core part made of a polyester resin and a sheath part made of a polyethylene resin was used as the heat-fusible fiber instead of the heat-extensible heat-fusible core-sheath type composite fiber. In the same manner as in Example 1, a nonwoven fabric of Example 5 was obtained.
Example 6
Example in which only a non-heat-extensible fiber having a core part made of a polyester resin and a sheath part made of a polyethylene resin was used as the heat-fusible fiber instead of the heat-extensible heat-fusible core-sheath type composite fiber. In the same manner as in Example 2, a nonwoven fabric of Example 6 was obtained.

Example 7
Implemented except that instead of heat-stretchable heat-fusible core-sheath type composite fiber, only non-heat-stretchable fiber consisting of polyester resin in the core and polyethylene resin in the sheath was used as the heat-fusible fiber A nonwoven fabric of Example 7 was obtained in the same manner as Example 3.
Example 8
Example in which only a non-heat-extensible fiber having a core part made of a polyester resin and a sheath part made of a polyethylene resin was used as the heat-fusible fiber instead of the heat-extensible heat-fusible core-sheath type composite fiber. In the same manner as in Example 4, the nonwoven fabric of Example 8 was obtained.

Example 9
As the heat-fusible fiber, in place of the heat-extensible heat-fusible core-sheath type composite fiber, the heat-fusible core-sheath type composite fiber used in Example 1 and the non-heat-stretching used in Example 5 What was mixed with the active fiber at a mass ratio of 1: 1 was used. Specifically, the fiber treatment agent A is immersed in the heat-extensible fiber and the non-heat-extensible fiber, and the fiber treatment agent A is adhered so that the amount of adhesion per gram is the same. It was produced by blending fibers. A nonwoven fabric of Example 9 was obtained in the same manner as Example 1 except that the heat-fusible fiber was used.
Example 10
As the heat-fusible fiber, in place of the heat-extensible heat-fusible core-sheath type composite fiber, the heat-fusible core-sheath type composite fiber used in Example 1 and the non-heat-stretching used in Example 5 What was mixed with the active fiber at a mass ratio of 1: 1 was used. Specifically, the heat-extensible fiber and the non-heat-extensible fiber are soaked with the content ratio of each component of the fiber treatment agent A (oil agent) changed to the ratio shown in Table 1, and each of them per 1 g. After attaching the said fiber treatment agent so that the adhesion amount might become the same, it produced by mixing those fibers. A nonwoven fabric of Example 10 was obtained in the same manner as Example 1 except that the heat-fusible fiber was used.

[Comparative Examples 1 and 2]
Nonwoven fabrics of Comparative Examples 1 and 2 were obtained in the same manner as in Example 1 except that the content ratio of each component of the fiber treatment agent A (oil agent) was changed to the ratios shown in Table 1. Specifically, the fiber treatment agent containing no component (A) in Comparative Example 1 and no component (C) in Comparative Example 2 was used.

[Comparative Examples 3 and 4]
The nonwoven fabrics of Comparative Examples 3 and 4 were obtained in the same manner as in Example 5 except that the content ratio of each component of the fiber treatment agent A (oil agent) was changed to the ratio shown in Table 1. Specifically, the fiber treatment agent that does not contain the component (A) in Comparative Example 3 and the component (C) in Comparative Example 4 was used.

[Method of measuring the amount of fiber treatment agent attached]
The adhesion amount of the fiber treatment agent was measured using a rapid residual oil extractor. 2 g of fiber was measured and placed in a predetermined container with a small hole at the bottom. Then, press the fiber with the lid, push the fiber into the bottom of the container, put 10cc ethanol / methanol (1: 1) mixed solution into it, let stand for 10 minutes, put the lid again, The ethanol / methanol component contained in the fiber was squeezed by pouring and the liquid was put into a weighing dish. The solvent was blown off by heating the weighing pan, and the amount of the fiber treatment agent adhered was measured by measuring the weight after heating from the original weight of the weighing pan. N = 3 was measured, and the average was defined as the oil adhesion amount.

[Evaluation]
[Contact angle]
About the nonwoven fabric obtained in Examples 1-10 and Comparative Examples 1-4, the contact angle of water with respect to the fiber taken out from the nonwoven fabric was measured. The results are shown in Table 1. About the nonwoven fabric obtained in Examples 1-8 and Comparative Examples 1-4, the contact angle of water with respect to the fiber taken out out of the nonwoven fabric was measured by the method of Paragraph [0057] of JP, 2010-168715, A did.
That is, an automatic contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used as a measuring device. Distilled water is used for contact angle measurement. The amount of liquid ejected from an ink jet type water droplet ejection part (manufactured by Cluster Technology Co., Ltd., pulse injector CTC-25 having a pore diameter of 25 μm) is set to 20 picoliters, and water droplets are directly above the fibers taken out from the nonwoven fabric. Dripping into. The state of dripping is recorded on a high-speed recording device connected to a horizontally installed camera. The recording device is preferably a personal computer incorporating a high-speed capture device from the viewpoint of image analysis or image analysis later. In this measurement, an image is recorded every 17 msec. In the recorded video, the first image of water drops on the fiber taken out from the nonwoven fabric is attached to the attached software FAMAS (software version is 2.6.2, analysis method is droplet method, analysis method is θ / 2 Method, image processing algorithm is non-reflective, image processing image mode is frame, threshold level is 200, and curvature correction is not performed). Calculate the contact angle.
N = 5 contact angles are measured to 1 digit after the decimal point, and a value obtained by averaging a total of 10 measured values (rounded to the second decimal place) is defined as each contact angle.
Moreover, about the nonwoven fabric obtained in Example 9 and 10, the heat | fever extensible fiber and the non-heat extensible fiber were extract | collected by the following method from the "convex part top part P1" and "back surface P2" of each nonwoven fabric, respectively, and extract | collected The contact angle of water with respect to each heat-extensible fiber and each non-heat-extensible fiber was measured by the same method.

[Method of collecting heat-extensible fibers and non-heat-extensible fibers]
From the blended nonwoven fabric, each fiber was cut from the outermost layer portion of the nonwoven fabric with a fiber length of 1 mm using precision scissors and tweezers and taken out from the nonwoven fabric.

  In Table 1, the “convex portion top portion P1” in the “contact angle” column is the top portion P1 of the convex portion 119 of the uneven surface 10b (the top portion of the thick portion), and the “back surface P2” is the convex portion on the flat surface 10a. It is a measurement result of the contact angle with the distilled water of the fiber taken out from the nonwoven fabric in the site | part P2 corresponding to the top part P1. The contact angle measurement results of Examples 1 and 2 and Comparative Example 1 are shown in FIG.

[Remaining amount of surface sheet liquid]
The surface sheet is removed from a commercially available sanitary napkin (trade name “Laurier Sarah Cushion Skin Clean Absorption”) of Kao Corporation, and instead, the nonwoven fabrics of Examples 1 to 10 and Comparative Examples 1 to 4 are laminated. The sanitary napkin for evaluation was obtained by fixing the periphery. Each nonwoven fabric was arranged with the back surface P2 side facing the absorber side.
On the surface of the sanitary napkin, an acrylic plate having a transmission hole with an inner diameter of 1 cm is overlapped, and a constant load of 100 Pa is applied to the napkin. Under such a load, 6.0 g of defibrinated horse blood is poured from the permeation hole of the acrylic plate. The acrylic plate is removed 60 seconds after pouring the horse blood, and then the weight (W2) of the nonwoven fabric is measured. The difference from the weight (W1) of the nonwoven fabric before pouring horse blood is measured in advance. (W2-W1) is calculated. The above operation is performed three times, and the average value of the three times is defined as the remaining liquid amount (mg). The liquid remaining amount is an index of how much the wearer's skin gets wet. The smaller the liquid remaining amount, the better the result. The results are shown in Table 1.

[Wetback amount]
The surface sheet is removed from a commercially available sanitary napkin (trade name “Laurier Sarah Cushion Skin Clean Absorption”) of Kao Corporation, and instead, the nonwoven fabrics of Examples 1 to 10 and Comparative Examples 1 to 4 are laminated. The sanitary napkin for evaluation was obtained by fixing the periphery. Each nonwoven fabric was arranged with the back surface P2 side facing the absorber side.
On the surface of the sanitary napkin, an acrylic plate having a transmission hole with an inner diameter of 1 cm is overlapped, and a constant load of 100 Pa is applied to the napkin. Under such a load, a total of 9.0 g of defibrinated horse blood is poured every 3.0 minutes from the permeation hole of the acrylic plate. The acrylic plate is removed 300 seconds after pouring the horse blood, and then a tissue paper is placed on the surface of the nonwoven fabric, and further, a weight is placed on the tissue paper, and a load of 2000 Pa is applied to the napkin. After 5 seconds from the stacking of the weight stones, the weight stones and the tissue paper are removed, the weight of the tissue paper (W4) is measured, and the weight of the tissue paper before being stacked on the surface of the nonwoven fabric (W3) measured in advance. ) (W4-W3) is calculated. The above operation is performed three times, and the average value of the three times is defined as a liquid return amount (mg). The smaller the liquid return amount, the higher the evaluation. The results are shown in Table 1.

[Liquid flow distance]
The surface sheet is removed from a commercially available sanitary napkin (trade name “Laurier Sarah Cushion Skin Clean Absorption”) of Kao Corporation, and instead, the nonwoven fabrics of Examples 1 to 10 and Comparative Examples 1 to 4 are laminated. The sanitary napkin for evaluation was obtained by fixing the periphery. Each nonwoven fabric was arranged with the back surface P2 side facing the absorber side.
The test apparatus has a mounting portion in which the mounting surface of the napkin is inclined 45 ° with respect to the horizontal plane. A napkin is placed on the placement portion so that the topsheet faces upward. As a test solution, colored distilled water is dropped onto the napkin at a rate of 1 g / 10 sec. First, the distance from the point where the nonwoven fabric gets wet to the point where the test liquid is first absorbed by the absorbent is measured. The above operation is performed three times, and the average of the three times is defined as the liquid flow distance (mm). The liquid flow distance is an index of the amount that the liquid touches the wearer's skin without being absorbed by the sanitary napkin. The shorter the liquid flow distance, the higher the evaluation.

[Bulk recoverability of nonwoven fabric]
The bulk recoverability of the nonwoven fabric was evaluated by the following method, and the results are shown in Table 1.
About the measuring method of the thickness of a nonwoven fabric, it carried out by the method as described in WO20110074207A1. For evaluation of the bulk recovery property, it was wound around a paper tube having an outer diameter of 85 mm in a roll shape with a length of 2700 m, then stored at room temperature for 2 weeks, and the rolled nonwoven fabric was fed out at a conveyance speed of 150 m / min and processed. The nonwoven fabric thickness is recovered by blowing hot air onto the nonwoven fabric at a temperature of 115 ° C. for a treatment time of 0.2 seconds and a wind speed of 2.8 m / second. The recoverability of the nonwoven fabric is when the thickness of the convex portion of the nonwoven fabric (thickness before storage) before winding the nonwoven fabric in a roll shape is C, and the thickness of the convex portion of the nonwoven fabric after hot air blowing (thickness after recovery) is D. Is represented by the following formula (2). The measurement of the nonwoven fabric thickness after hot air spraying is measured 1 minute to 1 hour after hot air spraying. The thickness of the nonwoven fabric is measured by the method described above.
Bulk recovery property (%) = ( D / C ) × 100 (2)
C when the bulk recoverability calculated by the formula (2) is less than 60%, B when 60% or more and less than 70%, A when 70% or more but less than 80%, and S when 80% or more. And evaluate. The higher the bulk recovery value, the higher the evaluation.

From the results shown in Table 1 and FIG. 3, in Examples 1 to 10 in which the components (A) to (C) were blended, Comparative Examples 1 and 3 in which the component (A) was not blended, and the (C ) It can be seen that the difference in hydrophilicity between the convex portion top portion P1 and the back surface P2 is larger than in Comparative Examples 2 and 4 which do not contain the component. Moreover, from the evaluation result of the liquid remaining amount shown in Table 1, the hydrophilic gradient obtained in Comparative Examples 1 and 2 was obtained by using the nonwoven fabric having a large hydrophilic gradient obtained in Examples 1 to 10 for the topsheet. As compared with the case of using a relatively small non-woven fabric, it can be seen that the liquid residue and the wetback amount on the surface of the surface sheet are reduced, and the absorbability is improved.
From the results shown in Table 1, it can be seen that in Examples 1 to 10, although the content of the component (A) is small, the liquid flow distance is short.

As is clear from the results shown in Table 1, Examples 5 and 6 using non-heat-extensible fibers as the heat-fusible fibers had good touch. Further, the amount of liquid remaining on the surface was larger than that of Examples 1 and 2, but smaller than that of Comparative Examples 3 and 4, and was sufficiently satisfactory.
Examples 9 and 10 using a mixture of heat-extensible fibers and non-heat-extensible fibers as the heat-fusible fibers have a good touch and a surface texture, as is apparent from the results shown in Table 1. The liquid residue has decreased.

DESCRIPTION OF SYMBOLS 10 Nonwoven fabric P1 Convex part top part P2 Back surface 11 Card machine 12 Web 13 Embossing apparatus 14 Embossing roll 15 Flat roll 17 Hot air processing apparatus

Claims (13)

A nonwoven fabric using heat-fusible fibers to which a fiber treatment agent is attached, wherein the fiber treatment agent comprises the following components (A), (B) and (C).
(A) polyorganosiloxane,
(B) an alkyl phosphate ester,
(C) Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)   The nonwoven fabric according to claim 1, wherein the polyorganosiloxane is contained in a proportion of 1% by mass to 30% by mass with respect to the total mass of the fiber treatment agent.   The nonwoven fabric according to claim 1 or 2, wherein the component (C) is a dialkylsulfonic acid or a salt thereof.   The nonwoven fabric according to any one of claims 1 to 3, wherein a content ratio (the former: the latter) of the component (A) and the component (C) is 1: 3 to 4: 1 by mass ratio.   The nonwoven fabric according to any one of claims 1 to 4, wherein the nonwoven fabric has a concavo-convex shape, and the hydrophilicity increases from the top to the bottom of the convex portion.   The nonwoven fabric according to any one of claims 1 to 5, wherein the heat-fusible fiber is a heat-extensible fiber whose length is extended by heat.   An absorbent article using the nonwoven fabric according to any one of claims 1 to 6. A fiber treatment agent for nonwoven fabric containing the following component (A), component (B) and component (C), wherein the content ratio of the component (A) to the component (C) (the former: the latter) is mass. The fiber treatment agent for nonwoven fabrics which is 1: 3-4: 1 by ratio, and (A) component is contained in the ratio of 30 mass% or less with respect to the mass of a fiber treatment agent.
(A) polyorganosiloxane,
(B) an alkyl phosphate ester,
(C) Anionic surfactant represented by the following general formula (1)

(In the formula, Z represents an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group or a linear or branched alkyl chain having 1 to 12 carbon atoms, which may contain a double bond; R ₁ and R ₂ each independently represents an ester group, an amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms, which may contain a double bond. , X represents —SO ₃ M, —OSO ₃ M or —COOM, and M represents H, Na, K, Mg, Ca or ammonium.)   The fiber treatment agent for nonwoven fabric according to claim 8, wherein the polyorganosiloxane is polydimethylsiloxane.   The polydimethylsiloxane is composed of two or more types of polydimethylsiloxane, one of which is composed of polydimethylsiloxane having a weight average molecular weight of 100,000 or more, and the other is composed of polydimethylsiloxane having a weight average molecular weight of less than 100,000. The fiber treatment agent for nonwoven fabrics of Claim 8 or 9.   The fiber treatment agent for nonwoven fabrics of any one of Claims 8-10 whose said (C) component is a dialkylsulfonic acid or its salt.   The heat-fusible fiber which the fiber processing agent of any one of Claims 8-11 adhered. The heat-fusible fiber according to claim 12, wherein the heat-fusible fiber is a heat-extensible fiber.

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