CN108368673B

CN108368673B - Non-woven fabric

Info

Publication number: CN108368673B
Application number: CN201680072271.5A
Authority: CN
Inventors: 寒川裕太; 蒲谷吉晃
Original assignee: Kao Corp
Current assignee: Kao Corp
Priority date: 2015-12-16
Filing date: 2016-12-07
Publication date: 2020-11-17
Anticipated expiration: 2036-12-07
Also published as: JP2017110328A; TW201736668A; WO2017104511A1; JP6310536B2; CN108368673A; TWI651449B; RU2696708C1

Abstract

The nonwoven fabric of the present invention contains a liquid film-splitting agent or the following compound and 1 or more selected from the following components (A), (B) and (C). A compound: a compound component (A) having a spreading coefficient of 15 or more with respect to a liquid having a surface tension of 50mN/m, and a water solubility of 0g or more and 0.025g or less: an anionic surfactant component (B) represented by the following general formula (S1): polyoxyalkylene-modified polyol fatty acid ester component (C): amphoteric surfactants having hydroxysulfobetaine groups

(wherein Z represents a group having a valence of 3 and selected from the group consisting of a linear or branched alkyl chain having 1 to 12 carbon atoms and optionally containing an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond; R⁷And R⁸Each independently represents a linear or branched alkyl group having 2 to 16 carbon atoms which may contain an ester group, an amide group, a polyoxyalkylene group, an ether group or a double bond; x represents-SO₃M、‑OSO₃M or-COOM, M represents H, Na, K, Mg, Ca or ammonium).

Description

Non-woven fabric

Technical Field

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

Background

In recent years, nonwoven fabrics used in absorbent articles have been proposed to improve liquid permeability and a dry feeling on the surface contacting the skin.

For example, patent document 1 describes a nonwoven fabric having a difference in hydrophilicity in the thickness direction by locally decreasing the hydrophilicity of a hydrophilic nonwoven fabric. When the hydrophilic nonwoven fabric is used as a topsheet of an absorbent article, for example, the amount of liquid remaining in the topsheet or the amount of liquid flowing on the surface of the topsheet can be reduced.

Patent document 2 describes a nonwoven fabric in which the absorption time of water droplets falling from a specific height is within a certain range in order to reduce the amount of liquid returned from the absorbent article. It is described that a hydrophilic treatment agent such as polyoxyalkylene-modified polysiloxane is used to set the absorption time. Patent document 3 describes that, in a diaper or the like, the outer surface of a top sheet that is in contact with the skin is covered with a lotion in order to prevent the adhesion of feces to the skin of the wearer.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2014/171388

Patent document 2: japanese patent laid-open publication No. 2004-256935

Patent document 3: japanese Kohyo publication Hei 11-510082

Disclosure of Invention

The invention provides a nonwoven fabric and a fiber treatment agent containing a liquid film cracking agent or the following compound and 1 or more selected from the following component (A), component (B) and component (C).

A compound: a compound having a spreading coefficient of 15 or more with respect to a liquid having a surface tension of 50mN/m and a water solubility of 0g to 0.025g

Component (A): an anionic surfactant represented by the following general formula (S1)

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 1]

(wherein Z represents a group having a valence of 3 and selected from the group consisting of a linear or branched alkyl chain having 1 to 12 carbon atoms which may contain an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond R⁷And R⁸Each independently represents a linear or branched alkyl group having 2 to 16 carbon atoms which may contain an ester group, an amide group, a polyoxyalkylene group, an ether group or a double bond. X represents-SO₃M、-OSO₃M or-COOM, M represents H, Na, K, Mg, Ca or ammonium).

The present invention also provides a nonwoven fabric and a fiber treatment agent containing the liquid film-splitting agent or the compound and 1 or more selected from the following component (a), component (B) and component (C).

A compound: a spreading factor of more than 0mN/m with respect to a liquid having a surface tension of 50mN/m, a water solubility of 0g or more and 0.025g or less, and an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50mN/m

Component (A): an anionic surfactant represented by the general formula (S1)

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

The above and other features and advantages of the present invention will become more apparent from the following description, with reference to the accompanying drawings where appropriate.

Drawings

Fig. 1 is a schematic view showing a liquid film formed in gaps between fibers of a nonwoven fabric.

FIG. 2(A1) to (A4) are explanatory views schematically showing a state where the liquid film cracking agent cracks the liquid film from the side surface; (B1) FIGS. B4 are explanatory views schematically showing the state in which the liquid film cracking agent cracks the liquid film from above.

FIG. 3 is a cross-sectional view of a nonwoven fabric showing a preferred embodiment of the nonwoven fabric of the present invention in terms of a gradient of hydrophilicity.

FIG. 4 is a cross-sectional view of a nonwoven fabric showing another preferred embodiment of the nonwoven fabric of the present invention, showing a gradient in hydrophilicity.

FIG. 5 is a cross-sectional view of a nonwoven fabric showing still another preferred embodiment of the gradient of hydrophilicity of the nonwoven fabric of the present invention.

FIG. 6 is a cross-sectional view of a nonwoven fabric showing still another preferred embodiment of the gradient of hydrophilicity of the nonwoven fabric of the present invention.

Fig. 7 is a cross-sectional view of a nonwoven fabric showing a preferred embodiment (embodiment 1) of the uneven shape of the nonwoven fabric of the present invention.

Fig. 8 is a perspective view schematically showing another preferred embodiment (embodiment 2) of the uneven shape of the nonwoven fabric of the present invention in a partial cross section.

Fig. 9 is a perspective view schematically showing a further preferred embodiment of the uneven shape of the nonwoven fabric of the present invention (embodiment 3) in a partial cross section, where (a) shows a nonwoven fabric composed of 1 layer, and (B) shows a nonwoven fabric composed of 2 layers.

Fig. 10 is a perspective view schematically showing still another preferred embodiment (embodiment 4) of the uneven shape of the nonwoven fabric of the present invention.

Fig. 11 is a perspective view showing a modified example of the nonwoven fabric shown in fig. 10.

Fig. 12 is a perspective view schematically showing still another preferred embodiment (embodiment 5) of the nonwoven fabric of the present invention, which has an uneven shape.

Fig. 13 is an explanatory view schematically showing a state in which the constituent fibers of the nonwoven fabric shown in fig. 12 are fixed to each other through the heat-fused portion.

Fig. 14(a) is a perspective view schematically showing still another preferred embodiment (embodiment 6) of the nonwoven fabric of the present invention, and (B) is a cross-sectional view showing a part of a cross section of the nonwoven fabric shown in (a) along the thickness direction, enlarged.

Fig. 15 is a schematic view showing a process for producing the nonwoven fabric shown in fig. 14 (a).

Fig. 16 is a perspective view schematically showing still another preferred embodiment (embodiment 7) of the nonwoven fabric of the present invention, which has an uneven shape.

Detailed Description

The invention provides a nonwoven fabric which can reduce a liquid film formed between fibers to improve low liquid residue performance and low liquid return performance, thereby realizing a higher level of dry touch, and a fiber treatment agent for obtaining the nonwoven fabric. The present invention also relates to a nonwoven fabric and a fiber treatment agent suitable for use in a topsheet of an absorbent article that achieves both low liquid retention performance and low rewet performance at a high level, and also achieves both a dry feel and a soft texture.

The nonwoven fabrics and surface sheets of patent documents 1 to 3 exhibit improved dry touch. However, nonwoven fabrics have narrow regions between fibers. Even if there is a space in this region through which excreted liquid (for example, urine or menstrual blood; also simply referred to as liquid) can pass, a stable liquid film is formed between the fibers and liquid easily remains because of meniscus capillary force between the fibers, surface activity due to plasma proteins, or high blood liquid surface viscosity. Further, urine also has surface activity due to phospholipids, and a liquid film is easily formed as described above. As described above, since various excretory liquids remain stably between fibers as a liquid film, there is a case where a little wetness is felt due to the liquid returning from the liquid film at the time of contact, and even in a nonwoven fabric using a conventional treatment agent or the like, the dry feeling is still unsatisfactory. Further, in recent years, consumers are also required to have a good touch to the skin in addition to a dry feeling, and therefore, finer fibers have come to be used. However, if thinner fibers are used, the space between the fibers becomes narrower. This further facilitates the generation of a liquid film between fibers, and the liquid film is less likely to break and more likely to remain.

Therefore, a technique for removing a liquid film formed in a narrow part between fibers in a nonwoven fabric is required. However, the liquid film is difficult to remove because of its high stability. The removal of the liquid film between the fibers is not described in the above patent documents 1 to 3. Further, it is also considered to apply a water-soluble surfactant to reduce the surface tension of the liquid to remove the liquid film. However, when such a surfactant is used for an absorbent article to remove a liquid film, there is a possibility that the liquid also permeates through the liquid-impervious backsheet.

Further, the liquid film removing performance by the water-soluble surfactant or the like may cause a slight amount of liquid to be returned in the reverse direction because a narrow space between fibers is maintained. For example, when the nonwoven fabric is used as a topsheet of an absorbent article such as a diaper, the liquid that has been once permeated may return to the skin-side surface of the nonwoven fabric a little from the space between fibers secured by the elimination of the liquid film, depending on the magnitude of the pressure (e.g., body pressure applied when the absorbent article is worn, etc.) or the like. In terms of the dryness of the nonwoven fabric surface, the amount of the liquid returned is desirably suppressed as little as possible, as in the case of a liquid film.

The nonwoven fabric and the fiber treatment agent of the present invention reduce a liquid film formed between fibers to improve low liquid residue performance and improve low liquid return performance, thereby realizing a higher level of dry touch. Further, by using the nonwoven fabric and the fiber treatment agent of the present invention, an absorbent article can be provided which can achieve both low liquid retention performance and low rewet performance at a high level and can achieve both dry feeling and soft touch.

The nonwoven fabric of the present invention contains 1 or more selected from the following components (a), (B) and (C) and the following compounds.

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 2]

(wherein Z represents a group having a valence of 3 and selected from the group consisting of a C1-12 straight or branched alkyl chain which may contain an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond; R⁷And R⁸Each independently represents a linear or branched alkyl group having 2 to 16 carbon atoms which may contain an ester group, an amide group, a polyoxyalkylene group, an ether group or a double bond; x represents-SO ₃M、-OSO₃M or-COOM, M represents H, Na, K, Mg, Ca or ammonium)

The nonwoven fabric of the present invention contains 1 or more selected from the group consisting of the above-mentioned component (a), component (B) and component (C) and the following compound.

The nonwoven fabric of the present invention contains 1 or more selected from the group consisting of the above-mentioned component (a), component (B) and component (C) as a liquid film-splitting agent.

The fiber treatment agent of the present invention contains 1 or more selected from the group consisting of the component (A), the component (B) and the component (C), and the content of the compound is 50% by mass or less.

The fiber-treating agent of the present invention contains 1 or more selected from the group consisting of the component (a), the component (B), and the component (C), and the content of the compound is 50% by mass or less.

The fiber treatment agent of the present invention contains a liquid film-splitting agent and 1 or more selected from the group consisting of the component (A), the component (B) and the component (C), and the content of the liquid film-splitting agent is 50% by mass or less.

The fiber treatment agent of the present invention is not limited to the case of being applied to fibers before nonwoven fabric formation and adhering to the fibers, and may be applied to fibers formed into a nonwoven fabric and adhering to the fibers.

The fiber treatment agent of the present invention may contain only the above-mentioned components, may contain other agents within a range not inhibiting the following effects, and may be in a state diluted with a solvent. The degree of dilution may be adjusted as appropriate depending on the purpose. Further, as the solvent, a substance which does not inhibit the following action may be used without particular limitation. Examples thereof include: water, methanol, ethanol, propanol, butanol, 1, 3-butanediol, and the like. Particularly, when used as a nonwoven fabric for an absorbent article, water, ethanol, 1, 3-butanediol, and the like are preferable in view of suppressing irritation to the skin and the like.

The liquid film-splitting agent is an agent which splits a liquid film formed between fibers or on the surface of fibers of a nonwoven fabric or inhibits the formation of a liquid film by bringing a liquid, such as a liquid having a relatively high viscosity such as menstrual blood or an excreted liquid such as urine, into contact with the nonwoven fabric, and has an action of splitting the formed liquid film and an action of inhibiting the formation of a liquid film. The former may be referred to as a primary role and the latter may be referred to as a secondary role. The liquid film is cracked by the action of the liquid film cracking agent pushing and destabilizing a part of the liquid film layer. The liquid film-splitting agent acts to facilitate the passage of liquid without leaving a narrow space between fibers of the nonwoven fabric. That is, the liquid film-splitting agent serves as a driving force for eliminating the liquid remaining in a liquid film shape between fibers, and the nonwoven fabric of the present invention has excellent liquid permeability. Thus, even if the fibers constituting the nonwoven fabric are thinned and the distance between the fibers is narrowed, both softness to the touch of the skin and suppression of liquid remaining are achieved. Such nonwoven fabrics are used, for example, as topsheet for absorbent articles such as sanitary napkins, diapers for infants, and diapers for adults.

(property of disappearing liquid film)

The liquid film breaking agent used in the present invention has a property of eliminating a liquid film, and by this property, when the liquid film breaking agent is applied to a test solution mainly containing a plasma component or artificial urine (composition: 1.940 mass% of urea, 0.795 mass% of sodium chloride, 0.110 mass% of magnesium sulfate, 0.062 mass% of calcium chloride, 0.197 mass% of potassium sulfate, 0.010 mass% of red No. 2 (dye), water (about 96.88 mass%), and polyethylene oxide lauryl ether (about 0.07 mass%), and the surface tension is adjusted to 53 ± 1dyne/cm (23 ℃), a liquid film eliminating effect can be exhibited. The liquid film disappearing effect here includes two effects, namely, an effect of suppressing the formation of a liquid film in a structure in which air is entrained by the liquid film formed from a test liquid or artificial urine; and an effect of making the formed structure disappear; an agent exhibiting at least one effect may be said to have a property that can exhibit a liquid film disappearing effect.

The test solution is a liquid component extracted from horse blood defibrinated (NIPPON BIOTEST Co., Ltd.). Specifically, when 100mL of defibrinated horse blood was allowed to stand at 22 ℃ and a humidity of 65% for 1 hour, the defibrinated horse blood was separated into an upper layer and a lower layer, and the upper layer was the test solution. The upper layer contains mainly plasma components and the lower layer contains mainly blood cell components. When only the upper layer is extracted from the defibrinated horse blood separated into the upper layer and the lower layer, for example, a pipette (Transfer pipette) (manufactured by kenshakia corporation) can be used.

Whether or not a certain agent has the "property of disappearing a liquid film" described above is judged by: in the state of the structure in which air is likely to be entrained by the liquid film formed by the test solution or artificial urine to which the agent is applied, the amount of the liquid film, which is the structure, is determined. That is, the test solution or artificial urine was adjusted to a temperature of 25 ℃ and 10g of the solution was added to a spiral tube (No. 5 manufactured by Maruemu, Inc., tube diameter of 27mm, total length of 55mm) to obtain a standard sample. Further, as a measurement sample, 0.01g of the agent to be measured which had been adjusted to 25 ℃ in advance was added to the same article as the standard sample. The standard sample and the measurement sample were vigorously shaken in such a manner that they were reciprocated 2 times in the vertical direction of the spiral tube, and then rapidly placed on a horizontal surface. By oscillating the sample, a liquid layer (lower layer) containing no structure and a structural body layer (upper layer) containing a large number of structures formed on the liquid layer are formed inside the oscillated spiral tube. Immediately after the end of the oscillation, 10 seconds later, the heights of the structure layers (the height from the liquid surface of the liquid layer to the upper surface of the structure layer) of both samples were measured. Then, when the height of the structural layer of the measurement sample is 90% or less of the height of the structural layer of the standard sample, the agent to be measured is considered to have a liquid film cracking effect.

The liquid film breaking agent used in the present invention is a single compound satisfying the above properties or a combination of a plurality of single compounds satisfying the above properties, or an agent satisfying the above properties (which can exhibit liquid film breaking) by a combination of a plurality of compounds. That is, the liquid film cracking agents are all limited to those having the liquid film cracking effect defined above. Therefore, in the case where the compound applied to the fiber treatment agent in the nonwoven fabric contains a third component which does not meet the above definition, a distinction is made from the liquid film-splitting agent.

The concept of "single compound" as to the liquid film cracking agent and the third component has the same composition formula, but includes compounds having different molecular weights depending on the number of repeating units.

On the other hand, the above-mentioned components (a), (B) and (C) provide a gradient of hydrophilicity in the thickness direction to the nonwoven fabric, and promote a driving force for absorbing a liquid from a place having a lower hydrophilicity to a place having a higher hydrophilicity.

Specifically, the above-mentioned components (a), (B) or (C) function as follows: the hydrophilic portion of each component is permeated into the fiber interior by heat treatment to give a hydrophilic degree gradient.

Since the alkyl group is bulky, the component (a) can penetrate into the fiber so as to surround the hydrophilic group. In particular, the presence of polyorganosiloxane facilitates penetration into the fiber.

Since the component (B) has a structure in which hydrophobic chains are easily arranged in a radial pattern and hydrophilic groups are easily surrounded, the component (B) is more likely to penetrate into the fibers even if the degree of hydrophilicity is higher than that of a surfactant having a normal linear hydrocarbon chain.

Since the component (C) has both anionic groups and cationic groups, when adsorbed on the fiber surface, the component (C) is inhibited from electrostatic repulsion with each other to be in a relatively dense state, and thus easily penetrates into the fiber. Since a hydroxyl group is present between the anionic group and the cationic group, the components (C) are more easily pulled together by the action of a hydrogen bond, and are in a relatively dense state. As a result, even when the amount of the component (C) added is small (thin film thickness), the component (C) can be adsorbed tightly to the fiber and a high degree of hydrophilicity can be imparted to the heat-fusible fiber having a small fiber diameter. Further, due to the characteristic that the hydrophilic group is easily accessible, the hydrophobic chain easily surrounds the hydrophilic group and easily penetrates into the inside of the fiber.

Further, the ease of penetration of each component into the fiber is related to the relationship of component (C) < component (A) < component (B).

Further, in the fiber-treating agent of the present invention, when the liquid film-splitting agent is a chemical structure having a main chain containing a silicon atom, for example, a structure having a polysiloxane chain as a main chain, the liquid film-splitting agent promotes penetration of the components (a), (B), or (C) having a hydrocarbon chain into the fiber. The reason is considered to be that: since the polysiloxane chain is not miscible with the alkyl chain of the component (a), (B) or (C), the component (a), (B) or (C) penetrates into the hydrophobic heat-fusible fiber which is more easily compatible when the fiber is heated and melted.

In a heat treatment process of a fiber web or a nonwoven fabric with such a fiber treatment agent, for example, a process of blowing hot air to a fiber web as one of processes of producing a hot air nonwoven fabric, a value of a contact angle of fibers changes depending on heat as described below. That is, the hot air blowing surface is naturally different from the surface (web surface) on the opposite side to the hot air blowing surface in the amount of heat to which the fibers in the fiber web are subjected. Thus, the fibers of the hot air blowing surface receive different amounts of heat from the fibers of the opposite side, and the fibers of the hot air blowing surface are: fibers that are less hydrophilic than the side opposite thereto, and have a higher contact angle. In this case, a gradient of hydrophilicity can be given in which the hydrophilicity increases from one surface (skin contact surface) side to the other surface (non-skin contact surface) side.

The above-mentioned hydrophilicity gradient means the following state unless otherwise specified: the nonwoven fabric has a higher degree of hydrophilicity on the side opposite to the liquid receiving surface (e.g., the skin contact surface in the case of a topsheet such as a diaper) in the thickness direction than on the side of the liquid receiving surface (e.g., the non-skin contact surface in the case of the topsheet). The "gradient" broadly includes various modes in which the difference in hydrophilicity is present between the liquid-receiving surface side and the opposite surface side, and may be a mode in which the hydrophilicity is gradually increased or a mode in which the hydrophilicity is gradually increased.

In the method for producing the nonwoven fabric of the present invention, if the hydrophilicity gradient can be formed by heat, the method is not limited to the hot air method, and any heat treatment method can be used.

As described above, the fiber treatment agent of the present invention can provide a liquid film splitting effect to a nonwoven fabric and appropriately control the hydrophilicity gradient in the thickness direction. In particular, in the case where the liquid film cracking agent has a chemical structure in which the main chain contains a silicon atom, for example, a chemical structure in which a polysiloxane chain is used as the main chain, it becomes easier to control the hydrophilicity gradient. Thus, the nonwoven fabric of the present invention can be suitably produced in various combinations of the liquid film-like liquid residue removing action by the liquid film-splitting agent and the liquid suction action by the hydrophilicity gradient.

In the nonwoven fabric of the present invention, the liquid film-splitting agent serves as a driving force for eliminating the remaining liquid in the form of a liquid film between the fibers, whereby the liquid can easily permeate between the fibers, and the hydrophilicity gradient system of the fibers based on the components (a), (B), or (C) acts as a driving force for allowing the liquid to permeate in one direction in the thickness direction with respect to the liquid permeating between the fibers. The hydrophilicity gradient of the fibers based on the components (a), (B), or (C) acts to suppress the liquid that has passed through once from returning to the opposite direction (from a place with a higher hydrophilicity to a place with a lower hydrophilicity), and even if the liquid returns slightly, the liquid is sucked back to the place with a higher hydrophilicity because the liquid film splitting agent does not allow the remaining amount of the liquid in the nonwoven fabric. That is, the combination of the liquid film-splitting agent and the above (a), (B) or (C) synergistically acts as a driving force for allowing liquid to pass through in one direction in the nonwoven fabric of the present invention.

Accordingly, the nonwoven fabric of the present invention 1 can suppress liquid retention at a high level regardless of the liquid properties (viscosity), and can suppress liquid return in the reverse direction even when pressure is applied. Therefore, the low liquid residue performance and the low liquid return performance are simultaneously achieved at a high level. This provides liquid permeability that can quickly respond to a new liquid. In addition, in this case, a nonwoven fabric having a soft touch feeling using relatively fine fibers can be obtained while maintaining a high level of dryness.

The fiber treatment agent of the present invention is contained by being applied to the constituent fibers in at least a partial region of the nonwoven fabric. At least a part to be coated with the fiber treatment agent of the present invention is preferably a part that receives the most liquid. For example, when the nonwoven fabric of the present invention is used as a topsheet of an absorbent article such as a sanitary napkin, it is a region that directly receives excretory fluids such as menstrual blood and the like corresponding to the excretory part of the wearer.

In the nonwoven fabric of the present invention, the liquid film-splitting agent is preferably contained in at least the surface on the side receiving the liquid in the thickness direction. The top sheet of the above example contains a liquid film cracking agent at least on the skin contact surface side that contacts the skin of the wearer. On the other hand, the component (a), the component (B) or the component (C) is preferably present in the entire thickness direction of the layer to which the hydrophilicity gradient is imparted.

The adhesion of the fiber treatment agent to the nonwoven fabric mainly means the adhesion to the surface of the fiber. However, the fiber treatment agent may be contained in the fiber, or may be present in the fiber by internal addition, if it remains on the surface of the fiber. In particular, from the viewpoint of effectively exhibiting the above-described action on the liquid film, from the viewpoint of providing a hydrophilic gradient based on the above-described components (a), (B), or (C), and from the viewpoint of production, the liquid film cracking agent is preferably left on the surface in a large amount, and is preferably a reagent (i.e., a reagent in which the hydrophilic group is suitably controlled) which has suppressed the water-solubility to a low level as possible and which has suitably preserved the hydrophilicity. In this respect, the following

embodiments

1 and 2 will be described.

As a method for adhering the fiber treatment agent to the surface of the fiber, various methods generally used can be employed without particular limitation. Examples thereof include: flexographic printing, ink jet printing, gravure printing, screen printing, spraying, brush coating, and the like. These treatments may be performed after the fibers are formed into a web by various methods, and thereafter, the web may be formed into a nonwoven fabric or incorporated into an absorbent article. For example, an air-laid nonwoven fabric is formed into a nonwoven fabric and then coated with the fiber treatment agent of the present invention.

The fiber or nonwoven fabric having the fiber treatment agent of the present invention adhered to the surface thereof is dried at a temperature sufficiently lower than the melting point of the fiber resin (for example, 120 ℃ or lower) by, for example, a hot air blowing type dryer. When the fiber treatment agent of the present invention is attached to the fiber by the above-mentioned attaching method, the fiber treatment agent may be treated in the form of a solution, emulsion, or dispersion using a solvent, a dispersion medium, or the like, as necessary.

The liquid film breaking agent of the present invention is required to be present in a liquid state when it comes into contact with a body fluid in order to have the liquid film breaking effect described below in the nonwoven fabric. In this respect, the melting point of the liquid film cracking agent of the present invention is preferably 40 ℃ or lower, more preferably 35 ℃ or lower. Further, the melting point of the liquid film cracking agent of the present invention is preferably-220 ℃ or higher, more preferably-180 ℃ or higher.

The amount of the fiber treatment agent of the invention adhering to the nonwoven fabric is preferably 0.10 mass% or more, more preferably 0.15 mass% or more, and even more preferably 0.20 mass% or more, from the viewpoint of the above-described action, in terms of the ratio relative to the total mass of the nonwoven fabric other than the fiber treatment agent. In addition, the upper limit thereof is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, and further preferably 1.0% by mass or less, from the viewpoint of mechanical contamination resistance. For example, the amount of the fiber treatment agent adhering to the nonwoven fabric is preferably 0.10 mass% or more and 5.0 mass% or less, more preferably 0.15 mass% or more and 3.0 mass% or less, and further preferably 0.20 mass% or more and 1.0 mass% or less in terms of the ratio to the total mass of the nonwoven fabric other than the fiber treatment agent.

The preferable content ratio of each component in the fiber treatment agent of the present invention is explained below.

The "fiber treatment agent" which is a reference for the content of the fiber treatment agent-containing components such as the liquid film-splitting agent or the components (a), (B) and (C) is not the "fiber treatment agent adhering to the nonwoven fabric" but the fiber treatment agent before adhering to the nonwoven fabric unless otherwise specified. In the case of attaching the fiber treatment agent to the nonwoven fabric, since the fiber treatment agent is usually diluted with an appropriate solvent such as water, the content of the fiber treatment agent-containing component, for example, the content of the component (a) in the fiber treatment agent can be based on the total mass of the diluted fiber treatment agent.

The following

embodiments

1 and 2, which are preferred embodiments of the nonwoven fabric containing a fiber treatment agent according to the present invention, will be described below.

(embodiment 1)

In the nonwoven fabric according to embodiment 1, the fiber treatment agent contains the component (a), the component (B), or the component (C) together with a liquid film-splitting agent which has a spreading factor of 15mN/m or more with respect to a liquid having a surface tension of 50mN/m and a water solubility of 0g or more and 0.025g or less.

The "spreading coefficient with respect to a liquid having a surface tension of 50 mN/m" possessed by the liquid film-disrupting agent means a spreading coefficient with respect to a liquid assumed to be an excreted liquid such as menstrual blood or urine as described above. The "spreading factor" is a value obtained based on the following formula (1) from a measurement value obtained by the following measurement method in an environmental region at a temperature of 25 ℃ and a Relative Humidity (RH) of 65%. The liquid film in the formula (1) is a liquid phase of "a liquid having a surface tension of 50 mN/m", and includes both a liquid in a state in which a film is formed between fibers or on the surface of the fibers and a liquid in a state before the film is formed, and is also simply referred to as a liquid. Further, the surface tension of the formula (1) means the interfacial tension of the liquid film and the gas phase interface of the liquid film cracking agent, and is different from the interfacial tension of the liquid film cracking agent and the liquid film between the liquid phases. This difference is also the same as in other descriptions in the present specification.

S＝γw－γo－γwo(Q1)

γ w: surface tension of liquid film (liquid)

γ o: surface tension of liquid film cracking agent

γ wo: interfacial tension of liquid film cracking agent and liquid film

From the formula (Q1), it is found that the spreading factor (S) of the liquid film cracking agent is determined by the surface tension (gamma) of the liquid film cracking agent_o) Become smaller and larger, and are caused by the interfacial tension (gamma) between the liquid film-splitting agent and the liquid film_wo) Becoming smaller and larger. When the spreading factor is 15mN/m or more, the liquid film-splitting agent has high mobility, that is, high diffusibility on the surface of the liquid film generated in the narrow region between the fibers. From this viewpoint, the spreading factor of the liquid film cracking agent is more preferably 20mN/m or more, still more preferably 25mN/m or more, and particularly preferably 30mN/m or more. On the other hand, the upper limit is not particularly limited, but according to the formula (Q1), in the case of using a liquid having a surface tension of 50mN/m, the upper limit is 50 mN/m; when a liquid having a surface tension of 60mN/m is used, the upper limit value is 60 mN/m; when a liquid having a surface tension of 70mN/m is used, the upper limit is 70mN/m, and therefore the surface tension of the liquid forming the liquid film becomes the upper limit. Therefore, in the present invention, from the viewpoint of using a liquid having a surface tension of 50mN/m, the upper limit of the spreading coefficient is 50mN/m or less.

The "water solubility" of the liquid film cracking agent is a value which is determined by the following determination method in an environmental region of 25 ℃ and 65% Relative Humidity (RH) based on the mass of the liquid film cracking agent which can be dissolved in 100g of deionized water. When the water solubility is 0g or more and 0.025g or less, the liquid film cracking agent is difficult to dissolve and forms an interface with the liquid film, and the above diffusibility is more effectively exhibited. From the same viewpoint, the water solubility of the liquid film-splitting agent is preferably 0.0025gThe amount of the surfactant is preferably 0.0017g or less, and more preferably less than 0.0001 g. The lower the water solubility, the better, and more than 0g, from the viewpoint of the diffusibility into a liquid film, it is practically 1.0X 10^-9g is above. The above water solubility is considered to be completely applicable to menstrual blood, urine, and the like containing water as a main component.

Surface tension (gamma) of the liquid film (liquid having a surface tension of 50 mN/m)_w) Surface tension (gamma) of liquid film cracking agent_o) Interfacial tension (gamma) between the liquid film cracking agent and the liquid film_wo) And the water solubility of the liquid film cracking agent were measured by the following methods.

When the nonwoven fabric to be measured is a member (for example, a topsheet) incorporated in an absorbent article such as a sanitary product or a disposable diaper, the nonwoven fabric is taken out and measured in the following manner. That is, in the absorbent article, an adhesive or the like used for bonding the member to be measured and another member is weakened by a cooling method such as cold spraying, and then the member to be measured is carefully peeled off and taken out. This taking-out method is suitable for the measurement of the nonwoven fabric of the present invention, such as the measurement of the distance between fibers and the fineness described below.

In the case of measuring the liquid film cracking agent adhering to the fibers, the fibers to which the liquid film cracking agent adheres are first washed with a washing liquid such as hexane, methanol, or ethanol, and the solvent used for the washing (the washing solvent including the liquid film cracking agent) is dried and then taken out. The mass of the substance taken out at this time is suitable for calculating the content ratio (OPU) of the liquid film cracking agent with respect to the mass of the fiber. When the amount of the substance to be taken out is small for measuring the surface tension or the interfacial tension, the structure of each component is identified by selecting an appropriate column and solvent depending on the constituent of the substance to be taken out, then separating each component by high performance liquid chromatography, and further performing MS (mass spectrometry) measurement, NMR (nuclear magnetic resonance) measurement, elemental analysis, or the like for each component. In addition, when the liquid film cracking agent contains a polymer compound, identification of the constituent components is facilitated by a method such as Gel Permeation Chromatography (GPC). If the substance is a commercially available product, it is purchased, and if the substance is not a commercially available product, it is synthesized to obtain a sufficient amount, and the amount is measured with respect to the surface tension or the interfacial tension. In particular, when the liquid film cracking agent obtained as described above is a solid, the surface tension and the interfacial tension are measured by heating to +5 ℃ which is the melting point of the liquid film cracking agent to cause phase transition to a liquid, and directly performing the measurement under the temperature conditions.

In addition, when the components of the fiber treatment agent attached to the nonwoven fabric of the present invention are analyzed, it is preferable to perform the analysis according to the above procedure.

(surface tension of liquid film (liquid) (. gamma.)_w) Method of measuring (1)

The measurement can be performed by a plate method (Wilhelmy method) using a platinum plate in an ambient region at a temperature of 25 ℃ and a Relative Humidity (RH) of 65%. As a measuring apparatus in this case, an automatic surface tensiometer "CBVP-Z" (trade name, manufactured by Kyowa Kagaku K.K.) can be used. As the platinum plate, a platinum plate having a purity of 99.9%, a size of 25mm in length and 10mm in width was used.

In the following measurement of the liquid film cracking agent, the "liquid having a surface tension of 50 mN/m" is a solution prepared by adding polyoxyethylene sorbitan monolaurate (for example, trade name RHEODOL SUPER TW-L120, manufactured by Kao corporation) as a nonionic surface active material to deionized water to adjust the surface tension to 50. + -.1 mN/m by the above-mentioned measurement method.

(surface tension (. gamma.) of liquid film-splitting agent_o) Method of measuring (1)

Surface tension (gamma) of liquid film_w) The measurement was carried out in the same manner by the plate method in an environmental region at a temperature of 25 ℃ and a Relative Humidity (RH) of 65% using the same apparatus. In the measurement, when the liquid film cracking agent obtained as described above is a solid, the liquid film cracking agent is heated to +5 ℃ of the melting point of the liquid film cracking agent to cause phase transition to a liquid, and the measurement is directly performed under the temperature condition.

(liquid film-splitting agent and liquid filmInterfacial tension (gamma) of_wo) Method of measuring (1)

The measurement can be carried out by the pendant drop method in an environmental region at a temperature of 25 ℃ and a Relative Humidity (RH) of 65%. As the measuring apparatus used in this case, an automatic interfacial viscoelasticity measuring apparatus (trade name THE TRACKER, manufactured by TECLIS-ITCONCEPT, Inc. or DSA25S, manufactured by KRUSS, Inc.) can be used. In the pendant drop method, a nonionic surface active substance contained in a liquid having a surface tension of 50mN/m starts to adsorb while forming a drop, and the interfacial tension decreases with the passage of time. Therefore, the interfacial tension at the time of forming the drop (at 0 second) was read. In addition, when the liquid film cracking agent obtained as described above is a solid, the measurement is performed by heating to the melting point of the liquid film cracking agent +5 ℃ to cause phase transition to a liquid, and the measurement is performed directly under the temperature condition.

In addition, when the difference in density between the liquid film cracking agent and the liquid having a surface tension of 50mN/m is very small or the viscosity is very high in the measurement of the interfacial tension, if the interfacial tension value is equal to or less than the measurement limit of the hanging drop agent, the measurement of the interfacial tension by the hanging drop method may be difficult. In this case, the measurement can be performed by a spin-drop method in an environmental region at a temperature of 25 ℃ and a Relative Humidity (RH) of 65%. As a measuring apparatus in this case, a spinning drop interfacial tension meter (product name SITE100, manufactured by KURUSS) can be used. In addition, for the measurement, the interfacial tension at the time of stable shape of the drop was also read, and when the obtained liquid film cracking agent was solid, the liquid film cracking agent was heated to the melting point of the agent +5 ℃ to cause phase transition to liquid, and the measurement was directly performed under the temperature condition.

When the interfacial tension can be measured by both of the above-described measuring apparatuses, a smaller value of the interfacial tension is used as the measurement result.

(method of measuring Water solubility of liquid film-splitting agent)

The obtained liquid film-breaking agent was gradually dissolved in an ambient region at a temperature of 25 ℃ and a Relative Humidity (RH) of 65% while stirring 100g of deionized water with a stirrer, and the amount of dissolution at the time when dissolution was no longer observed (suspension, precipitation, and cloudiness were observed) was defined as water solubility. Specifically, the measurement was performed by adding 0.0001g of reagent. As a result, the amount of 0.0001g of the compound was "less than 0.0001 g", the amount of 0.0001g of the compound was 0.0001g of the compound, and the amount of 0.0002g of the compound was "0.0001 g". In the case where the liquid film-breaking agent is a surfactant, "dissolution" means both monodispersed dissolution and micellar dispersed dissolution, and the amount of dissolution at the time of suspension, precipitation, or cloudiness is considered to be water solubility.

The liquid film-splitting agent of the present embodiment has the above spreading factor and water solubility, and thus can push away a layer of the liquid film from the vicinity of the center of the liquid film without being dissolved and diffused on the surface of the liquid film. This destabilizes the liquid film and causes cracking.

Here, the above-described action of the liquid film cleavage agent in the nonwoven fabric of the present embodiment will be specifically described with reference to fig. 1 and 2.

As shown in fig. 1, in a narrow region between fibers, a liquid film 2 is easily formed by a highly viscous liquid such as menstrual blood or an excreted liquid such as urine. In contrast, the liquid film-splitting agent destabilizes the liquid film to break the film, thereby suppressing the formation of the liquid film and promoting the liquid discharge from the nonwoven fabric. First, as shown in fig. 2(a1) and (B1), the liquid film breaking agent 3 included in the fibers 1 of the nonwoven fabric moves on the surface of the liquid film 2 while maintaining the interface with the liquid film 2. Then, as shown in fig. 2(a2) and (B2), the liquid film cracking agent 3 pushes apart a part of the liquid film 2 and penetrates in the thickness direction, and as shown in fig. 2(A3) and (B3), the liquid film 2 is gradually made uneven and changed to a thin film. As a result, as shown in fig. 2(a4) and (B4), the liquid film 2 is cracked by forming a gap. The liquid such as cracked menstrual blood becomes droplets and further easily passes through the space between fibers of the nonwoven fabric, thereby reducing the liquid residue. The action of the liquid film-splitting agent on the liquid film is not limited to the case of the liquid film between fibers, and similarly acts on the liquid film wound around the fiber surface. That is, the liquid film disruption agent may move over the liquid film wound around the fiber surface, thereby pushing apart a portion of the liquid film to disrupt the liquid film. In addition, even if the liquid film-splitting agent does not move at a position where the liquid film-splitting agent is attached to the fibers, the liquid film is split by the hydrophobic effect, and the formation of the liquid film can be suppressed.

As described above, in the present invention, the liquid film cleavage agent does not reduce liquid modification such as surface tension of the liquid film, but cleaves the liquid film itself generated between fibers or on the fiber surface while pushing it open, thereby suppressing the formation of the liquid film and promoting the liquid discharge from the nonwoven fabric. This can reduce the liquid residue in the nonwoven fabric. When such a nonwoven fabric is incorporated as a topsheet in an absorbent article, liquid retention between fibers is suppressed, and a liquid-permeable path to the absorbent body is ensured. This improves the liquid permeability, suppresses the flow of the liquid on the surface of the sheet, and improves the liquid absorption rate. In particular, the absorption rate of liquid such as menstrual blood having a high viscosity and easily remaining between fibers can be increased. Further, contamination such as red in the topsheet is less noticeable, and the absorbent article is comfortable and highly reliable in that the absorbent capacity can be reliably perceived.

In the present embodiment, the liquid film cleavage agent preferably has an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50 mN/m. That is, the value of the spreading factor (S) in the above formula (Q1) is defined as 1 variable of the "interfacial tension (γ) between the liquid film-splitting agent and the liquid film _wo) "preferably 20mN/m or less. By "interfacial tension (gamma) of the liquid film cleavage agent and the liquid film_wo) "the suppression is low, the spreading factor of the liquid film cracking agent is increased, and the liquid film cracking agent becomes easy to move from the fiber surface to the vicinity of the center of the liquid film, so that the above-mentioned effect becomes more remarkable. From this viewpoint, "the interfacial tension with respect to a liquid having a surface tension of 50 mN/m" of the liquid film cracking agent is more preferably 17mN/m or less, still more preferably 13mN/m or less, yet more preferably 10mN/m or less, particularly preferably 9mN/m or less, and particularly preferably 1mN/m or less. On the other hand, the lower limit is not particularly limited, and from the viewpoint of insolubility in a liquid film, it is preferably more than 0 mN/m. When the interfacial tension was 0mN/m, that is, when the dissolution was carried out, the dissolution was impossibleSince the interface between the liquid-forming film and the liquid film-splitting agent does not hold the formula (Q1), the expansion of the agent does not occur.

As for the spreading coefficient, the numerical value thereof changes depending on the surface tension of the liquid to be treated, as can be seen from the formula. For example, when the surface tension of the object liquid is 72mN/m, the surface tension of the liquid film opener is 21mN/m, and the interfacial tension thereof is 0.2mN/m, the spreading coefficient is 50.8 mN/m.

When the surface tension of the object liquid was 30mN/m, the surface tension of the liquid film-breaking agent was 21mN/m, and the interfacial tension thereof was 0.2mN/m, the spreading coefficient was 8.8 mN/m.

In any case, the greater the spreading factor, the greater the liquid film splitting effect becomes.

In the present specification, the numerical value at a surface tension of 50mN/m is defined, but even if the surface tensions are different, the numerical value relationship of the spreading coefficients of the substances does not change, and therefore, even if the surface tension of the body fluid changes due to daily physical conditions or the like, the reagent having a large spreading coefficient exhibits an excellent liquid film splitting effect.

In the present embodiment, the surface tension of the liquid film cleavage agent is preferably 32mN/m or less, more preferably 30mN/m or less, still more preferably 25mN/m or less, and particularly preferably 22mN/m or less. The lower the surface tension, the better, and the lower limit is not particularly limited. The liquid film cracking agent is substantially 1mN/m or more in terms of durability.

By setting the surface tension of the liquid film cracking agent to the above range or less, the liquid film cracking action can be effectively exerted even when the surface tension of the liquid to be formed into the liquid film is reduced.

The content ratio of the liquid film-splitting agent in the fiber treatment agent is preferably 5% by mass or more, more preferably 15% by mass or more, and still more preferably 25% by mass or more, relative to the total mass of the fiber treatment agent, from the viewpoint of ensuring the liquid film-splitting performance. From the viewpoint of emulsion stability of the fiber treatment agent, it is preferably 50% by mass or less, more preferably less than 40% by mass, and even more preferably 30% by mass or less. The content ratio of the liquid film cracking agent is preferably 5% by mass or more and 50% by mass or less, more preferably 15% by mass or more and less than 40% by mass, and still more preferably 25% by mass or more and 30% by mass or less.

In the fiber-treating agent, the content ratio of the liquid film-splitting agent to the component (a) is preferably 1: 1.6 to 1: 0.6, more preferably 1: 1.3 to 1: 0.9.

in the fiber treatment agent, the content ratio of the liquid film-splitting agent to the component (B) is preferably 1: 2-3: 1, more preferably 1: 1-2: 1.

in the fiber-treating agent, the content ratio of the liquid film-splitting agent to the component (C) is preferably 1: 1.6 to 1: 0.6, more preferably 1: 1.3 to 1: 0.9.

(embodiment 2)

Next, the nonwoven fabric of embodiment 2 will be described.

The nonwoven fabric according to embodiment 2 contains the above-mentioned component (a), component (B) or component (C) together with a liquid film-splitting agent, which has a spreading factor of more than 0mN/m, i.e., a positive value, with respect to a liquid having a surface tension of 50mN/m, a water solubility of 0g or more and 0.025g or less, and an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50mN/m, in the fiber-treating agent. Setting the "interfacial tension with respect to a liquid having a surface tension of 50 mN/m" as described above to 20mN/m or less means: as described above, the liquid film spreading property of the liquid film cracking agent is improved. Thus, even when the "spreading factor with respect to a liquid having a surface tension of 50 mN/m" is relatively small, such as the "spreading factor with respect to a liquid having a surface tension of 15 mN/m", the spreading factor is relatively high, and therefore, the liquid film is dispersed into the liquid film from the fiber surface in a large amount, and the liquid film is pushed away at a large amount, whereby the same action as in the case of embodiment 1 can be exerted.

The "spreading factor with respect to a liquid having a surface tension of 50 mN/m", "water solubility", and "interfacial tension with respect to a liquid having a surface tension of 50 mN/m" of the liquid film-breaking agent are defined in the same manner as in embodiment 1, and the measurement methods thereof are also the same.

In the present embodiment, the "interfacial tension with respect to a liquid having a surface tension of 50 mN/m" is preferably 17mN/m or less, more preferably 13mN/m or less, even more preferably 10mN/m or less, even more preferably 9mN/m or less, and particularly preferably 1mN/m or less, from the viewpoint of more effectively exhibiting the above-described action of the liquid film opener. The lower limit is not particularly limited as in embodiment 1, and is actually greater than 0mN/m from the viewpoint of not dissolving in a liquid film (liquid having a surface tension of 50 mN/m).

Further, the "spreading coefficient with respect to a liquid having a surface tension of 50 mN/m" is preferably 9mN/m or more, more preferably 10mN/m or more, and further preferably 15mN/m or more, from the viewpoint of more effectively exerting the above-described action of the liquid film opener. The upper limit is not particularly limited, but is actually 50mN/m or less from the viewpoint that the surface tension of the liquid forming the liquid film becomes the upper limit according to the formula (Q1).

Further, more preferable ranges of the surface tension and water solubility of the liquid film cracking agent are the same as those of embodiment 1.

In the nonwoven fabric according to embodiment 2, the content ratios of the liquid film-splitting agent, the component (a), the component (B), and the component (C) to the total mass of the fiber-treating agent are preferably within the numerical ranges shown in embodiment 1. The content ratios of the liquid film cracking agent to each of the component (a), the component (B), and the component (C) are also preferably within the numerical ranges shown in embodiment 1.

(phosphate type anionic surfactant)

In the nonwoven fabric according to embodiment 1 and the nonwoven fabric according to embodiment 2, the fiber treatment agent of the present invention to be used preferably further contains a phosphate ester type anionic surfactant. As a result, the hydrophilicity of the fiber surface is increased, and the wettability is improved, whereby the area of the liquid film in contact with the liquid film cracking agent is increased; further, since blood or urine has a surface active material having a phosphate group derived from a living body, by using a surfactant having a phosphate group in combination, the compatibility with the surfactant is improved, and further, the affinity with a phospholipid contained in blood or urine is also improved, so that the liquid film breaking agent is easily moved to the liquid film, and the breaking of the liquid film is further promoted.

Further, when the phosphate ester type anionic surfactant is formed into a nonwoven fabric after the fiber treatment agent containing the phosphate ester type anionic surfactant is applied to the fiber, the characteristics such as the card passing property of raw cotton or the uniformity of a fiber web can be improved, thereby improving the productivity of the nonwoven fabric and preventing the quality from being degraded. In addition, the emulsion stability of the fiber treatment agent containing the liquid film cracking agent of the present invention can be also improved.

In the fiber treatment agent of the present invention, the content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) is preferably 1.8 or less, more preferably 1.5 or less, and further preferably 1.2 or less in terms of mass ratio, from the viewpoint of ensuring that the card passing property of raw cotton or the uniformity of a fiber web is constant or more. The content ratio is preferably 0.1 or more, more preferably 0.25 or more, and still more preferably 0.5 or more, from the viewpoint of ensuring that the liquid film cracking performance is constant or more.

The phosphate ester type anionic surfactant can be used without particular limitation. Specific examples thereof include: alkyl ether phosphates, dialkyl phosphates, alkyl phosphates, and the like. Among them, alkyl phosphates are preferable from the viewpoint of enhancing affinity with a liquid film and imparting a function of processability to a nonwoven fabric.

As the alkyl ether phosphate, various ones can be used without particular limitation. Examples thereof include: phosphate esters having a saturated carbon chain such as polyoxyalkylene stearyl ether phosphate, polyoxyalkylene myristyl ether phosphate, polyoxyalkylene lauryl ether phosphate, and polyoxyalkylene palmityl ether phosphate; and phosphates having unsaturated carbon chains and side chains on these carbon chains, such as polyoxyalkylene oleoyl ether phosphate and polyoxyalkylene palmityl ether phosphate. More preferred are fully or partially neutralized salts of mono or di polyoxyalkylene alkyl ether phosphates having carbon chains of 16 to 18. Further, as the polyoxyalkylene group, there may be mentioned: polyoxyethylene, polyoxypropylene, and polyoxybutylene, and those obtained by copolymerizing these constituent monomers. Further, as the salt of alkyl ether phosphate, there may be mentioned: alkali metals such as sodium and potassium, ammonia, various amines, and the like. The alkyl ether phosphate may be used singly or in combination of two or more.

Specific examples of the alkyl phosphate include: substances having a saturated carbon chain such as stearyl phosphate, myristyl phosphate, lauryl phosphate, and palmityl phosphate; and substances having unsaturated carbon chains and side chains on these carbon chains, such as oleyl phosphate and palmitoleic acid phosphate (an ester of palmitoleic acid and phosphoric acid). More preferably, the salt is a completely or partially neutralized salt of a monoalkyl phosphate or dialkyl phosphate having a carbon chain of 16 to 18. Further, as the salt of alkyl phosphate, there may be mentioned: alkali metals such as sodium and potassium, ammonia, various amines, and the like. The alkyl phosphate may be used singly or in combination of two or more.

The content ratio of the phosphate ester type anionic surfactant in the fiber treatment agent adhering to the fibers is preferably 5% by mass or more, more preferably 10% by mass or more, with respect to the total mass of the fiber treatment agent, in terms of card passing property, uniformity of the fiber web, and the like. In addition, from the viewpoint of not hindering the effect of promoting the penetration of the substance having a chemical structure in which the main chain contains a silicon atom into the inside of the fiber having the hydrocarbon chain component by the heat treatment, 60 mass% or less is preferable, and 30 mass% or less is more preferable.

Next, specific examples of the liquid film cracking agent, the component (a), the component (B), and the component (C) in embodiment 1 and embodiment 2 will be described. The specific examples of the liquid film breaking agent described below exhibit the function of breaking the liquid film by having the property of not dissolving in water or having poor water solubility when the specific numerical value is within the above-mentioned range. On the other hand, the surfactant and the like conventionally used as a fiber treatment agent are practically dissolved in water and used in a substantially water-soluble state, and are not the liquid film cracking agent of the present invention.

(liquid film cracking agent)

The liquid film cracking agent in embodiment 1 and embodiment 2 is preferably a compound having a mass average molecular weight of 500 or more. The mass average molecular weight greatly affects the viscosity of the liquid film cracking agent. The liquid film-splitting agent has a high viscosity, and therefore, the liquid is less likely to flow down when passing through the space between fibers, and the durability of the liquid film-splitting effect in the nonwoven fabric can be maintained. From the viewpoint of viscosity to sufficiently sustain the liquid film cracking effect, the mass average molecular weight of the liquid film cracking agent is more preferably 1000 or more, still more preferably 1500 or more, and particularly preferably 2000 or more. On the other hand, from the viewpoint of maintaining the viscosity of the liquid film cracking agent which causes the liquid film cracking agent to move from the fiber containing the liquid film cracking agent to the liquid film, 50000 or less, more preferably 20000 or less, and still more preferably 10000 or less. The mass average molecular weight was measured by Gel Permeation Chromatography (GPC) "CCPD" (trade name, manufactured by Tosoh corporation). The measurement conditions are as follows. Further, the calculation of the converted molecular weight was performed with polystyrene.

Separating the tubular column: GMHHR-H + GMHHR-H (cation)

Dissolving and separating liquid: l Farmin DM20/CHCl3

Flow rate of solvent: 1.0ml/min

Temperature of the separation column: 40 deg.C

The liquid film cracking agent in embodiment 1 is preferably a compound having at least 1 structure selected from the following structures X, X-Y and Y-X-Y.

Structure X represents: < C (A) - (C represents a carbon atom, <, > and-represent a bond, the same shall apply hereinafter), -C (A)₂-、-C(A)(B)-、＞C(A)-C(R¹)＜、＞C(R¹)-、-C(R¹)(R²)-、-C(R¹)₂-, > C < and, -Si (R)¹)₂O-、-Si(R¹)(R²) Any repeating basic structure of O-, or a siloxane chain having a combination of 2 or more structures, or a mixed chain thereof. Structure X is terminated by a hydrogen atom, or is selected from-C (A)₃、-C(A)₂B、-C(A)(B)₂、-C(A)₂-C(R¹)₃、-C(R¹)₂A、-C(R¹)₃or-OSi (R)¹)₃、-OSi(R¹)₂(R²)、-Si(R¹)₃、-Si(R¹)₂(R²) At least 1 group selected from the group consisting of,

r mentioned above¹Or R²Each independently represents various substituents such as a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms, for example, preferably a methyl group, an ethyl group, and a propyl group), an alkoxy group (preferably having 1 to 20 carbon atoms, for example, preferably a methoxy group and an ethoxy group), an aryl group (preferably having 6 to 20 carbon atoms, for example, preferably a phenyl group), and a halogen atom (for example, preferably a fluorine atom). A. B independently represents a hydroxyl group, a carboxylic acid group, an amine group, an amide group, an imine group, a phenol group, or other substituent group containing an oxygen atom or a nitrogen atom. In structure X R ¹、R²And A, B may be the same or different from each other when there are a plurality of them. Further, the bond between C (carbon atom) or Si to be bonded is usually a single bond, but may contain a double bond or a triple bond, and the bond between C or Si may contain an ether group (-O-), an amide group (-CONR)^A-：R^AA hydrogen atom or a monovalent group), an ester group (-COO-), a carbonyl group (-CO-), a carbonate group (-OCOO-), and the like. The number of bonds between one C and Si and the other C or Si is 1 to 4, and there may be a long silicone chain (siloxane chain) or a mixed chain branch, or a radial structure.

Y represents a hydrophilic group having hydrophilicity and containing an atom selected from the group consisting of a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a phosphorus atom, and a sulfur atom. Examples of the hydrophilic group include a hydroxyl group, a carboxylic acid group, an amine group, an amide group, an imine group, a phenol group, and a polyoxyalkylene group (the number of carbons of the oxyalkylene group is preferably 1 to 4; for example, a Polyoxyethylene (POE) group, a polyoxypropylene (POP) group), a sulfonic acid group, a sulfuric acid group, a phosphoric acid group, a sulfobetaine group, a carbonylbetaine group, a phosphobetaine group (these betaine groups are betaine residues obtained by removing 1 hydrogen atom from each betaine compound), a quaternary ammonium group, and the like, alone or in combination. In addition to these, the following M may be mentioned ¹The groups and functional groups listed in (1). When a plurality of Y are used, they may be the same or different.

In structures X-Y and Y-X-Y, Y is bonded to X, or to a group at the X terminus. In the case of a group in which Y is bonded to the X terminal, the X terminal group is bonded to Y by removing the same number of hydrogen atoms and the like as the number of bonds to Y, for example.

In this structure, the hydrophilic group Y, A, B is selected from the specifically described groups so as to satisfy the spreading factor, water solubility, and interfacial tension described above. Thus, the intended liquid film cracking effect is exhibited.

The liquid film cleavage agent is preferably a compound having a siloxane structure as structure X. Further, the liquid film cracking agent is preferably a compound containing a siloxane chain in which structures represented by the following formulae (1) to (11) are arbitrarily combined as specific examples of the above-mentioned structures X, X-Y, Y-X-Y. Further, from the viewpoint of the liquid film cracking effect, the compound preferably has a mass average molecular weight within the above range.

[ chemical formula 3]

In formulae (1) to (11), M¹、L¹、R²¹And R²²Represents the following 1-valent or multi-valent (2-valent or more than 2-valent) group. R²³And R²⁴Represents a group having 1 or more valences (2 or more valences) or a single bond.

M¹A group having a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group having a combination of these groups; or a hydrophilic group having a plurality of hydroxyl groups such as an erythritol group, a xylitol group, a sorbitol group, a glyceryl group, or a glycol group (a hydrophilic group obtained by removing 1 hydrogen atom from the above-mentioned compound having a plurality of hydroxyl groups such as erythritol), a hydroxyl group, a carboxylic acid group, a mercapto group, an alkoxy group (preferably having 1 to 20 carbon atoms, for example, a methoxy group), an amino group, an amide group, an imino group, a phenol group, a sulfonic acid group, a quaternary ammonium group, a sulfobetaine group, a hydroxysulfobetaine group, a phosphobetaine group, an imidazolium betaine group, a carbonylbetaine group, an epoxy group, a carbinol group, a (meth) acryloyl group, or a functional group combining these groups. Furthermore, in M ¹In the case of polyvalent groupsM1 represents a group obtained by removing 1 or more hydrogen atoms from each of the above groups or functional groups.

L¹Represents an ether group or an amino group (which may be L)¹With amino groups consisting of > NR^C(R^CRepresents a hydrogen atom or a monovalent group)), an amide group, an ester group, a carbonyl group, or a carbonate group.

R²¹、R²²、R²³And R²⁴Each independently represents an alkyl group (preferably having 1 to 20 carbon atoms, for example, preferably methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, decyl), an alkoxy group (preferably having 1 to 20 carbon atoms, for example, preferably methoxy, ethoxy), an aryl group (preferably having 6 to 20 carbon atoms, for example, preferably phenyl), a fluoroalkyl group, or an aralkyl group, or a hydrocarbon group having a combination of these groups, or a halogen atom (for example, preferably a fluorine atom). Further, in R²²And R²³The polyvalent group means a polyvalent hydrocarbon group obtained by removing 1 or more hydrogen atoms or fluorine atoms from the hydrocarbon group.

In addition, in R²²Or R²³And M¹In the case of bonding, R may be²²Or R²³Examples of the group to be used include R in addition to the above-mentioned groups, the above-mentioned hydrocarbon group and halogen atom³²The imino group used.

Among them, the liquid film cracking agent is preferably a compound having a structure represented by any one of the formulae (1), (2), (5) and (10) as X, and having a structure represented by any one of the formulae other than these formulae as the terminal of X or a group containing the terminal of X and Y. Further preferred are compounds comprising: and a siloxane chain having at least 1 structure represented by any one of the above formulae (2), (4), (5), (6), (8) and (9) and having X or a group including the end of X and Y.

Specific examples of the above-mentioned compounds include organically modified silicones (polysiloxanes) as silicone surfactants. Examples of the organic modified silicone modified with a reactive organic group include: amino-modified, epoxy-modified, carboxyl-modified, glycol-modified, carbinol-modified, (meth) acryloyl-modified, mercapto-modified, phenol-modified silicones. Further, as the organic modified silicone modified with a non-reactive organic group, there can be mentioned: polyether modification (including polyoxyalkylene modification), methyl styrene modification, long chain alkyl modification, higher fatty acid ester modification, higher alkoxy modification, higher fatty acid modification, fluorine modified silicone, etc. Depending on the kind of the organic modification, for example, the spreading factor that exerts the liquid film splitting action described above can be obtained by appropriately changing the molecular weight of the silicone chain, the modification ratio, the number of moles of the modified group added, and the like. Here, the term "long chain" means that the number of carbon atoms is 12 or more, preferably 12 to 20. The term "higher" means that the number of carbon atoms is 6 or more, preferably 6 to 20.

Among these, as the liquid film cleavage agent for modified silicone, for example, polyoxyalkylene-modified silicone, epoxy-modified silicone, carbinol-modified silicone, glycol-modified silicone, and the like are preferable modified silicones having a structure in which at least one oxygen atom is contained in the modified group, and polyoxyalkylene-modified silicone is particularly preferable. Since the polyoxyalkylene-modified silicone has a silicone alkyl chain, the polyoxyalkylene-modified silicone is difficult to penetrate into the fiber and is likely to remain on the surface. Further, addition of a hydrophilic polyoxyalkylene chain is preferable because affinity with water is improved and interfacial tension is low, and thus the polyoxyalkylene chain is likely to move on the surface of the liquid film. Further, even when hot melt processing such as embossing is performed, the polyoxyalkylene-modified silicone is likely to remain on the fiber surface in this portion, and the liquid film cracking effect is less likely to be reduced. In particular, the liquid film splitting action is preferably exhibited in the embossed portion where liquid is likely to accumulate.

The polyoxyalkylene-modified silicone may be represented by the following formulas [ I ] to [ IV ]. Further, from the viewpoint of the liquid film cracking effect, the polyoxyalkylene-modified silicone preferably has a mass average molecular weight within the above range.

[ chemical formula 4]

[ chemical formula 5]

[ chemical formula 6]

[ chemical formula 7]

In the formula, R³¹Represents an alkyl group (preferably having 1 to 20 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, decyl) is preferable. R³²Represents a single bond or an alkylene group (preferably having 1 to 20 carbon atoms, for example, methylene, ethylene, propylene, butylene) and preferably represents the above-mentioned alkylene group. Plural R³¹A plurality of R³²Respectively, are identical to or different from each other. M¹¹Represents a group having polyoxyalkylene, preferably polyoxyalkylene. Examples of the polyoxyalkylene group include: polyoxyethylene, polyoxypropylene, and polyoxybutylene groups obtained by copolymerizing these constituent monomers. m and n are each independently an integer of 1 or more. The symbols of these repeating units are defined by the respective formulae (I) to (IV), and may not necessarily represent the same integer, but may be different.

The polyoxyalkylene-modified silicone may have either or both of a polyoxyethylene-modified group and a polyoxypropylene-modified group. Further, in order to be insoluble in water and have a low interfacial tension, it is desirable that the alkyl group R of the silicone chain is ³¹Having a methyl group. The substance having such a modified group or silicone chain is not particularly limited, and there is, for example, a paragraph [0006 ] of Japanese unexamined patent publication No. 2002-]And [0012 ]]The substance as described in (1). More specifically, there may be mentioned: polyethylene Oxide (POE) polyoxypropylene (POP) modified silicone, or polyepoxideEthane (POE) modified silicone, polyoxypropylene (POP) modified silicone, and the like. Examples of POE-modified silicones include: POE (3) -modified dimethyl silicone to which 3 moles of POE were added. As the POP-modified silicone, there can be mentioned: POP (10) -modified dimethylsilicone, POP (12) -modified dimethylsilicone, POP (24) -modified dimethylsilicone and the like, to which 10 moles, 12 moles or 24 moles of POPs are added.

The spreading factor and the water solubility of embodiment 1 described above can be set within specific ranges in the case of the polyoxyalkylene-modified silicone, for example, depending on the number of moles of polyoxyalkylene added (the number of oxyalkylene bonds forming the polyoxyalkylene group per 1 mole of the polyoxyalkylene-modified silicone), the modification ratio described below, and the like. In the liquid film cracking agent, the respective specific ranges may be set as in the case of surface tension and interfacial tension.

From the above viewpoint, the number of moles of the polyoxyalkylene added is preferably 1 or more. If the amount is less than 1, the above-mentioned liquid film cracking effect is reduced because the interfacial tension is increased and the spreading factor is reduced. From this viewpoint, the number of addition mols is more preferably 3 or more, and still more preferably 5 or more. On the other hand, if the number of addition mols is too large, the resulting polymer becomes hydrophilic and the water solubility becomes high. From this viewpoint, the addition mole number is preferably 30 or less, more preferably 20 or less, and further preferably 10 or less.

The modification ratio of the modified silicone is preferably 5% or more, more preferably 10% or more, and still more preferably 20% or more, because the hydrophilicity is impaired when the modification ratio is too low. If too high, the amount is preferably 95% or less, more preferably 70% or less, and still more preferably 40% or less, because the polymer dissolves in water. The modification ratio of the modified silicone is a ratio of the number of repeating units of the modified siloxane bond to the total number of repeating units of the siloxane bond in the molecule of the modified silicone 1. For example, (n/m + n). times.100% in the above formulas [ I ] and [ IV ], (2/m). times.100% in the formula [ II ], and (1/m). times.100% in the formula [ III ].

In addition, regarding the spreading factor and the water solubility, in the case of the polyoxyalkylene-modified silicone, in addition to the above, the spreading factor and the water solubility may be set to specific ranges by the following methods, respectively: and water-soluble polyoxyethylene and water-insoluble polyoxypropylene and polyoxybutylene groups are used as modifying groups; changing the molecular weight of the water-insoluble silicone chain; and modified groups such as amino groups, epoxy groups, carboxyl groups, hydroxyl groups, and carbinol groups, in addition to polyoxyalkylene modified groups.

The polyalkylene-modified silicone usable as a liquid film-splitting agent is preferably contained in an amount of 0.02 mass% or more and 5.0 mass% or less in terms of a content ratio (Oil Per Unit) based on the mass of the fiber. The content ratio (OPU) of the polyalkylene-modified silicone is more preferably 1.0 mass% or less, and still more preferably 0.40 mass% or less. This makes the nonwoven fabric less sticky and has a good feel. In addition, the content ratio (OPU) is more preferably 0.04% by mass or more, and still more preferably 0.10% by mass or more, from the viewpoint of sufficiently exerting the liquid film splitting effect by the polyalkylene-modified silicone.

The liquid film cracking agent in embodiment 2 is preferably a compound having at least 1 structure selected from the following structures Z, Z-Y and Y-Z-Y.

Structure Z represents: > C (A) - (C: carbon atom), -C (A)₂-、-C(A)(B)-、＞C(A)-C(R³)＜、＞C(R³)-、-C(R³)(R⁴)-、-C(R³)₂A hydrocarbon chain having 2 or more kinds of repeating basic structures or combinations thereof. Having a hydrogen atom at the terminus of structure Z, or selected from-C (A)₃、-C(A)₂B、-C(A)(B)₂、-C(A)₂-C(R³)₃、-C(R³)₂A、-C(R³)₃At least 1 group.

R mentioned above³Or R⁴Each independently represents a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, decyl), an alkoxy group (preferably having 1 to 20 carbon atoms, for example, methoxy, ethoxy), an aryl group (preferably having 6 to 20 carbon atoms, for example, phenyl), a fluoroalkyl group, an aralkyl group, or a combination thereof Various substituents such as hydrocarbon groups and fluorine atoms. A. And B independently represents a hydroxyl group, a carboxylic acid group, an amino group, an amide group, an imino group, a phenol group, or a substituent containing an oxygen atom or a nitrogen atom. In structure X R³、R⁴A, B are the same or different from each other when a plurality of them are present. The bond between C (carbon atoms) to be bonded is usually a single bond, but may contain a double bond or a triple bond, and the bond between C may contain a linking group such as an ether group, an amide group, an ester group, a carbonyl group, or a carbonate group. The number of bonds between one C and another C is 1 to 4, and there may be cases where the hydrocarbon chain of a long chain is branched or has a radial structure.

Y represents a hydrophilic group having hydrophilicity and containing an atom selected from the group consisting of a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a phosphorus atom, and a sulfur atom. For example, hydroxyl, carboxylic acid, amino, amide, imino, phenolic groups; or a polyoxyalkylene group (the number of carbon atoms of the oxyalkylene group is preferably 1 to 4. for example, a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group in which these groups are combined is preferable); or a hydrophilic group having a plurality of hydroxyl groups such as an erythritol group, a xylitol group, a sorbitol group, a glycerin group, or an ethylene glycol group; or hydrophilic groups such as a sulfonic acid group, a sulfuric acid group, a phosphoric acid group, a sulfobetaine group, a carbonylbetaine group, a phosphobetaine group, a quaternary ammonium group, an imidazolium betaine group, an epoxy group, a carbinol group, and a methacryl group, alone or in combination. When a plurality of Y are used, they may be the same or different.

In the structures Z-Y and Y-Z-Y, Y is bonded to Z or a group at the end of Z. In the case where Y is bonded to the terminal group of Z, the terminal group of Z is bonded to Y by removing the same number of hydrogen atoms and the like as the number of bonds to Y, for example.

In this structure, the hydrophilic group Y, A, B is selected from the specifically described groups so as to satisfy the spreading factor, water solubility, and interfacial tension. Thus, the intended liquid film cracking effect is exhibited.

The liquid film cleavage agent is preferably a compound obtained by arbitrarily combining structures represented by the following formulae (12) to (25), which are specific examples of the structure Z, Z-Y, Y-Z-Y. Further, from the viewpoint of the liquid film cracking effect, the compound preferably has a mass average molecular weight within the above range.

[ chemical formula 8]

In formulae (12) to (25), M²、L²、R⁴¹、R⁴²And R⁴³Represents the following 1-valent or polyvalent group (2-valent or more than 2-valent).

M²A group having a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group having a combination of these groups; or a hydrophilic group having a plurality of hydroxyl groups such as an erythritol group, a xylitol group, a sorbitol group, a glyceryl group, or a glycol group, a hydroxyl group, a carboxylic acid group, a mercapto group, an alkoxy group (preferably having 1 to 20 carbon atoms, for example, preferably a methoxy group), an amino group, an amide group, an imino group, a phenol group, a sulfonic acid group, a quaternary ammonium group, a sulfobetaine group, a hydroxysulfobetaine, a phosphobetaine, an imidazolium betaine, a carbonylbetaine, an epoxy group, a methanol group, a (meth) acryloyl group, or a functional group combining these groups.

L²And represents a bonding group such as an ether group, an amino group, an amide group, an ester group, a carbonyl group, a carbonate group, or a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group in which these groups are combined.

R⁴¹、R⁴²And R⁴³Each independently represents various substituents including a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms, for example, preferably methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, decyl), an alkoxy group (preferably having 1 to 20 carbon atoms, for example, preferably methoxy, ethoxy), an aryl group (preferably having 6 to 20 carbon atoms, for example, preferably phenyl), a fluoroalkyl group, an aralkyl group, a hydrocarbon group having a combination of these groups, or a halogen atom (for example, preferably a fluorine atom).

At R⁴²In the case of polyvalent groupsUnder the condition of R⁴²Each of the substituents is a group obtained by removing 1 or more hydrogen atoms from each substituent.

The bond in each structure may be optionally bonded to another structure, and a hydrogen atom may be introduced.

Specific examples of the above-mentioned compounds include, but are not limited to, the following compounds.

As the 1 st stage, polyether compounds or nonionic surfactants are exemplified. Specifically, there may be mentioned: polyoxyalkylene alkyl (POA) ether represented by the formula (V), or polyoxyalkylene glycol having a mass average molecular weight of 1000 or more represented by the formula (VI), steareth, beheneth, PPG myristyl ether, PPG stearyl ether, PPG behenyl ether, or the like. As the polyoxyalkylene alkyl ether, lauryl ether to which POP is added in an amount of 3 to 24 moles, preferably 5 moles, is preferable. The polyether compound is preferably a polypropylene glycol having a mass average molecular weight of 1000 to 10000, preferably 3000, to which 17 to 180 moles, preferably about 50 moles, of polypropylene glycol (PPG) are added. The mass average molecular weight can be measured by the above-described measurement method.

The polyether compound or the nonionic surfactant is preferably contained in a content ratio (Oil Per Unit) of 0.10 mass% or more and 5.0 mass% or less with respect to the mass of the fiber. The content ratio (OPU) of the polyether compound or the nonionic surfactant is more preferably 1.0% by mass or less, and still more preferably 0.40% by mass or less. This makes the nonwoven fabric less sticky and has a good feel. In addition, the content ratio (OPU) is more preferably 0.15% by mass or more, and still more preferably 0.20% by mass or more, from the viewpoint of sufficiently exerting the liquid film splitting effect by the polyether compound or the nonionic surfactant.

[ chemical formula 9]

[ chemical formula 10]

In the formula, L²¹And represents a bonding group such as an ether group, an amino group, an amide group, an ester group, a carbonyl group, a carbonate group, a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group in which these groups are combined. R⁵¹And represents various substituents including a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, a nonyl group, a decyl group, a methoxy group, an ethoxy group, a phenyl group, a fluoroalkyl group, an aralkyl group, a hydrocarbon group in which these groups are combined, or a fluorine atom. In addition, a, b, m and n are each independently an integer of 1 or more. Here, C _mH_nRepresents alkyl (n ═ 2m +1), C_aH_bRepresents an alkylene group (a ═ 2 b). The number of carbon atoms and the number of hydrogen atoms are independently defined in each of the formulae (V) and (VI), and may not necessarily represent the same integer or may be different. In the following formulae (VII) to (XV), m ', n ', and n ' are also the same. Furthermore, - (C)_aH_bO)_m"m" of (A-B-C) is an integer of 1 or more. The values of the repeating units are independently determined in each of the formulae (V) and (VI), and may not necessarily represent the same integer or may be different.

The spreading factor, surface tension and water solubility of embodiment 2 can be set to specific ranges in the case of the polyether compound or the nonionic surfactant, depending on the number of moles of the polyoxyalkylene group, for example. From this viewpoint, the molar number of the polyoxyalkylene group is preferably 1 or more and 70 or less. If the amount is less than 1, the interfacial tension is high, and the liquid film cracking action is weak. From this viewpoint, the number of moles is more preferably 5 or more, and still more preferably 7 or more. On the other hand, the addition mole number is preferably 70 or less, more preferably 60 or less, and further preferably 50 or less. This is preferable because the linkage of the molecular chains is appropriately weakened and the diffusibility in the liquid film is excellent.

In addition, regarding the above spreading factor, surface tension, interfacial tension and water solubility, in the case of a polyether compound or a nonionic surfactant, each of them can be set to a specific range as follows: the water-soluble polyoxyethylene and the water-insoluble polyoxypropylene and the water-insoluble polyoxybutylene are used together; varying the chain length of the hydrocarbon chain; by using hydrocarbon chains with branches; a hydrocarbon chain having a double bond is used; using a hydrocarbon chain having a benzene ring or a naphthalene ring; or a suitable combination of the above.

The 2 nd hydrocarbon compound having 5 or more carbon atoms is exemplified. The number of carbon atoms is preferably 100 or less, more preferably 50 or less, from the viewpoint that the liquid is more likely to spread on the surface of the liquid film. The hydrocarbon compound is not limited to a linear chain and may be a branched chain except for polyorganosiloxane, and the chain is not particularly limited to a saturated chain and an unsaturated chain. Further, the compound may have a substituent such as an ester or an ether in the middle or at the end. Among them, a substance which is liquid at ordinary temperature may be preferably used alone. The content of the hydrocarbon compound is preferably 0.10 mass% or more and 5.0 mass% or less in terms of the content ratio (Oil Per Unit) with respect to the mass of the fiber. The content ratio (OPU) of the hydrocarbon compound is preferably 1.0% by mass or less, more preferably 0.99% by mass or less, and still more preferably 0.40% by mass or less. Thus, the top sheet is not sticky and has a good feel. In addition, the content ratio (OPU) is more preferably 0.15% by mass or more, and still more preferably 0.20% by mass or more, from the viewpoint of sufficiently exerting the liquid film cracking effect by the hydrocarbon compound.

As the hydrocarbon compound, there can be mentioned: an oil or fat, such as a natural oil or natural fat. Specific examples thereof include: coconut oil, camellia oil, castor oil, cocoa butter, corn oil, olive oil, sunflower oil, tall oil, mixtures thereof, and the like.

Further, there may be mentioned: fatty acids represented by the formula (VII) such as caprylic acid, capric acid, oleic acid, lauric acid, palmitic acid, stearic acid, myristic acid, behenic acid, and mixtures thereof.

[ chemical formula 11]

C_mH_n-COOH [VII]

Wherein m and n are each independently an integer of 1 or more. Here, C_mH_nThe hydrocarbon group of each of the above fatty acids is represented.

Examples of linear or branched, saturated or unsaturated, substituted or unsubstituted polyol fatty acid esters or mixtures of polyol fatty acid esters include: as the glycerin fatty acid ester or pentaerythritol fatty acid ester represented by the formula (VIII-I) or (VIII-II), specifically, there can be mentioned: tricaprylin, tripalmitin, mixtures thereof, and the like. Further, the mixture of glycerin fatty acid esters or pentaerythritol fatty acid esters typically contains a few monoesters, diesters, and triesters. Preferred examples of the glycerin fatty acid ester include: mixtures of tricaprylin, tricaprin (グリセリルトリカプリエート), and the like. In addition, from the viewpoint of obtaining a higher spreading factor by reducing the interfacial tension, a polyol fatty acid ester in which a polyoxyalkylene group is introduced to such an extent that water insolubility can be maintained may also be used.

[ chemical formula 12]

[ chemical formula 13]

Wherein m, m ', n ' and n ' are each independently an integer of 1 or more. The plurality of m and the plurality of n are respectively the same or different from each other. Here, C_mH_n、C_m′H_n' and C_m″H_n"respectively represents the hydrocarbon group of each of the above-mentioned fatty acids.

Examples of the fatty acid or fatty acid mixture in which a linear or branched, saturated or unsaturated fatty acid forms an ester with a polyhydric alcohol having a plurality of hydroxyl groups, and a part of the hydroxyl groups remain without being esterified include: a glycerin fatty acid ester represented by any one of the formulae (IX), formula (X), or formula (XI), or a partial ester of a sorbitan fatty acid ester or a pentaerythritol fatty acid ester. Specifically, there may be mentioned: ethylene glycol monomyristate, ethylene glycol dimyristate, ethylene glycol palmitate, ethylene glycol dipalmitate, glycerol dimyristate, glycerol dipalmitate, glycerol monooleate, sorbitan monostearate, sorbitan dioleate, sorbitan tristearate, pentaerythritol monostearate, pentaerythritol dilaurate, pentaerythritol tristearate, mixtures thereof, and the like. Further, the mixture containing a partial ester such as a glycerin fatty acid ester, a sorbitan fatty acid ester, or a pentaerythritol fatty acid ester typically contains a plurality of completely esterified compounds.

[ chemical formula 14]

Wherein m and n are each independently an integer of 1 or more. The plurality of m and the plurality of n are respectively the same or different from each other. Here, C_mH_nThe hydrocarbon group of each of the above fatty acids is represented.

[ chemical formula 15]

In the formula, R⁵²Represents a linear or branched, saturated or unsaturated hydrocarbon group (such as an alkyl group, an alkenyl group, or an alkynyl group) having 2 to 22 carbon atoms. Specifically, there may be mentioned: 2-ethylhexyl, lauryl, myristyl, palmityl, stearyl, behenyl, oleyl, linoleyl, and the like.

[ chemical formula 16]

Further, there may be mentioned: sterols, phytosterols, and sterol derivatives. Specific examples thereof include: cholesterol, sitosterol, stigmasterol, ergosterol, mixtures thereof, and the like having the sterol structure of formula (XII).

[ chemical formula 17]

Specific examples of the alcohol include: lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, cetostearyl alcohol, behenyl alcohol represented by formula (XIII), and mixtures thereof.

[ chemical formula 18]

C_mH_n-OH [XIII]

Wherein m and n are each independently an integer of 1 or more. Here, C _mH_nRepresents a hydrocarbon group of each of the above-mentioned alcohols.

Specific examples of the fatty acid ester include: isopropyl myristate represented by the formula (XIV), isopropyl palmitate, cetyl ethylhexanoate, glyceryl triisooctanoate, octyldodecyl myristate, ethylhexyl palmitate, ethylhexyl stearate, butyl stearate, myristyl myristate, stearyl stearate, cholesteryl isostearate, and mixtures thereof.

[ chemical formula 19]

C_mH_n-COO-C_mH_n [XIV]

Wherein m and n are each independently an integer of 1 or more. Here, two C_mH_nMay be the same or different. C_mH_nC of-COO-_mH_nThe hydrocarbon group of each of the above fatty acids is represented. -COOC_mH_nC of (A)_mH_nRepresents a hydrocarbon group derived from an ester-forming alcohol.

Specific examples of the wax include: ozokerite represented by formula (XV), paraffin, vaseline, mineral oil, liquid isoparaffin, etc.

[ chemical formula 20]

C_mH_n [XV]

Wherein m and n are each independently an integer of 1 or more.

The spreading factor, surface tension, water solubility, and interfacial tension of embodiment 2 above can be set to specific ranges in the case of the hydrocarbon compound having 5 or more carbon atoms as follows: for example, a hydrophilic polyoxyethylene group is introduced in a small amount to such an extent that water insolubility can be maintained; introducing a polyoxypropylene or polyoxybutylene group which is hydrophobic but can reduce the interfacial tension; varying the chain length of the hydrocarbon chain; use of hydrocarbon chains having branches; a hydrocarbon chain having a double bond is used; a hydrocarbon chain having a benzene ring or a naphthalene ring, etc. is used.

The nonwoven fabric of the present invention may contain other components as needed in addition to the liquid film-splitting agent described above. The liquid film cracking agent of embodiment 1 and the liquid film cracking agent of embodiment 2 may be used in combination with both agents, in addition to the forms used for each. This aspect is also the same for the 1 st compound and the 2 nd compound in the liquid film cracking agent of the 2 nd embodiment.

Further, specific examples of the component (a), the component (B), or the component (C) of the fiber treatment agent in embodiment 1 and embodiment 2 are as follows.

(component (A))

The anionic surfactant represented by the following general formula (S1) of the component (a) means a component containing no phosphate ester type anionic surfactant. Further, the component (A) may be used alone in 1 kind or in combination of 2 or more kinds.

[ chemical formula 21]

(wherein Z represents a group having a valence of 3 and selected from the group consisting of a linear or branched alkyl chain having 1 to 12 carbon atoms which may contain an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond R⁷And R⁸Each independently represents an ester group which may be containedA linear or branched alkyl group having 2 to 16 carbon atoms in the group, amide group, polyoxyalkylene group, ether group or double bond. X represents-SO ₃M、-OSO₃M or-COOM, M represents H, Na, K, Mg, Ca or ammonium).

X in the general formula (S1) is-SO₃The anionic surfactant in which M, i.e., the hydrophilic group, is a sulfo group or a salt thereof includes, for example: dialkyl sulfonic acids or their salts. The number of carbon atoms of each alkyl group in the 2-chain of the dialkylsulfonic acid is preferably 4 or more and 14 or less, particularly 6 or more and 10 or less.

X in the formula (S1) is-OSO₃M, i.e., the anionic surfactant in which the hydrophilic group is a sulfate group or a salt thereof, includes: dialkyl sulfates.

Examples of the anionic surfactant in which X in the general formula (S1) is — COOM, that is, the hydrophilic group is a carboxyl group or a salt thereof include: a dialkyl carboxylic acid.

Specific examples of the above-mentioned compounds include: the substance described in paragraphs [0034] to [0041] of the specification of International publication No. 2014/171388.

As described above, by using the fiber treatment agent containing the liquid film splitting agent together with the component (a), the hydrophilicity of the nonwoven fabric treated with the fiber treatment agent is likely to be lowered by the heat treatment. The reason for this is that: the easiness of the penetration of the component (a) by the heat treatment into the fiber is influenced, and further, in the case where the liquid film-splitting agent has a main chain containing a silicon atom, for example, a polysiloxane chain, the penetration of the anionic surfactant having an alkyl chain of 2 or more chains into the fiber is further promoted by the part. This tends to reduce the hydrophilicity of the fiber surface by heat treatment. The reason is presumed to be: since the polysiloxane chain is not compatible with the alkyl chain of the anionic surfactant, the anionic surfactant penetrates into the hydrophobic heat-fusible fiber which is more compatible when the fiber is heated and melted.

(component (B))

The polyoxyalkylene-modified polyol fatty acid ester of the component (B) is a substance which is disposed in the fiber treatment agent so as to significantly reduce the hydrophilicity of a desired portion of the nonwoven fabric, that is, to significantly reduce the hydrophilicity of the desired portion in the nonwoven fabric, and is one of nonionic surfactants. The polyoxyalkylene-modified polyol fatty acid ester is one of polyol fatty acid esters obtained by esterifying the hydroxyl group of a polyol with a fatty acid, and is a modified product obtained by adding an alkylene oxide to the polyol fatty acid ester. The polyoxyalkylene-modified polyol fatty acid ester can be produced by a conventional method, and can be produced, for example, according to Japanese patent application laid-open No. 2007-91852.

Examples of the polyol which is one of the raw materials of the polyoxyalkylene-modified polyol fatty acid ester (or polyol fatty acid ester) of the component (B) include: ethylene glycol, diethylene glycol, polyethylene glycol (molecular weight 200-11000), propylene glycol, dipropylene glycol, polypropylene glycol (molecular weight 250-4000), 1, 3-butylene glycol, glycerol, polyglycerol (polymerization degree 2-30), erythritol, xylitol, sorbitol, mannitol, inositol, sorbitan esters (sorbide), sucrose, trehalose, isomalt, lactosucrose, cyclodextrin, maltitol, lactitol, isomalt (Palatinit), Panitol, reduced maltose, and the like. Polyethylene glycol, glycerin, erythritol, sorbitol, sorbitan esters, and sucrose are preferable, and sorbitol, sorbitan, and sorbitan esters are particularly preferable.

Examples of the fatty acid as another raw material of the polyoxyalkylene-modified polyol fatty acid ester (or polyol fatty acid ester) include: saturated or unsaturated fatty acids having 6 to 22 carbon atoms, mixed fatty acids containing these as main components, or branched fatty acids having 8 to 36 carbon atoms. The fatty acid may also partially contain hydroxyl groups. Specifically, there may be mentioned: octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, cis-9-octadecenoic acid, eicosanoic acid, docosanoic acid, tetracosanoic acid, hexacosanoic acid, octacosanoic acid, 2-ethylhexanoic acid, isostearic acid, etc., coconut oil fatty acid and tallow fatty acid derived from natural mixed fatty acids may be used, fatty acids having 8 to 18 carbon atoms are preferred, and dodecanoic acid, octadecanoic acid, and cis-9-octadecenoic acid are particularly preferred.

In the polyol fatty acid ester constituting the polyoxyalkylene-modified polyol fatty acid ester, in the case of increasing the hydrophobic chain to increase the hydrophobicity, the main component is preferably an esterified product of a ternary or higher alcohol and the esterification rate of the alcohol component is 90% or more, from the viewpoint of forming a shape which is easily penetrated into the fiber by not linearly increasing the shape of the molecule but three-dimensionally increasing the shape of the molecule. Here, the main component is the largest component among the polyol fatty acid esters, and is preferably contained in an amount of 50 mass% or more based on the total mass of the polyol fatty acid esters. For example, glycerin is exemplified as the trihydric alcohol, erythritol is exemplified as the tetrahydric alcohol, and xylitol is exemplified as the pentahydric alcohol.

As the polyol fatty acid ester constituting the polyoxyalkylene-modified polyol fatty acid ester, castor oil (hydrogenated castor oil) is particularly preferable. Castor oil is a glycerin fatty acid ester supplied from seeds of castor oil, which is a plant of the family euphorbiaceae, and about 90% of the constituent fatty acids are ricinoleic acid. That is, as the polyoxyalkylene-modified polyol fatty acid ester, ester oil of glycerol and fatty acid mainly composed of ricinoleic acid is preferable.

In the polyoxyalkylene-modified polyol fatty acid ester, examples of the alkylene oxide to be added to the polyol fatty acid ester include: ethylene oxide, propylene oxide, butylene oxide, and the like. As the polyoxyalkylene-modified polyol fatty acid ester, a Polyethylene Oxide (POE) -modified polyol fatty acid ester in which the alkylene oxide added to the polyol fatty acid ester is ethylene oxide is particularly preferable, and a POE-modified castor oil (POE-modified hydrogenated castor oil) in which the polyol fatty acid ester is castor oil (hydrogenated castor oil) is particularly preferable.

In the polyoxyalkylene-modified polyol fatty acid ester, the number of moles of alkylene oxide added to the polyol fatty acid ester is preferably more than 20 moles, and particularly preferably 40 moles or more, from the viewpoint of improving the liquid absorption performance of the nonwoven fabric (e.g., reducing the amount of residual liquid or reducing the amount of liquid flow). However, if the addition mole number of the alkylene oxide is too large, the hydrophilicity of the nonwoven fabric may be too high, and for example, when the nonwoven fabric is used as a topsheet in an absorbent article, the liquid-remaining amount may increase, and therefore, the addition mole number is preferably 80 moles or less, and more preferably 60 moles or less.

(component (C))

The amphoteric surfactant having a hydroxysulfobetaine group of the component (C) has the property of being closely adhered to the surface of the fiber as described above. Therefore, the amphoteric surfactant having a hydroxysulfobetaine group as the component (C) can realize high hydrophilization of fibers having a reduced fiber diameter, which is difficult to realize with a conventional fiber treatment agent.

The amphoteric surfactant having a hydroxysulfobetaine group is specifically a surfactant represented by the following general formula (S2).

[ chemical formula 26]

In the formula, R⁹Represents an alkyl group having 6 to 24 carbon atoms. Among them, the carbon number is more preferably 8 or more, further preferably 10 or more, further preferably 22 or less, further preferably 18 or less, from the viewpoint of forming a close adsorption surface on the fiber surface due to hydrophobic interaction based on hydrocarbon groups in addition to close adsorption of sulfobetaine groups.

More specifically, lauryl hydroxysultaine, myristyl hydroxysultaine, palmityl hydroxysultaine, stearyl hydroxysultaine may be used.

As the amphoteric surfactant having a hydroxysulfobetaine group, any of the above-mentioned agents may be used alone or in combination of 2 or more.

(other Components)

The nonwoven fabric of the present invention may contain other components as needed in addition to the above components in the fiber treatment agent. For example, a treatment agent such as an adhesion preventing agent such as a water-soluble modified silicone may be added to prevent the fibers from adhering to each other due to the fiber treatment agent and becoming a cause of foreign matter. In addition, an anionic, cationic, zwitterionic, nonionic surfactant or the like may be contained as another component. Specific examples of these surfactants include those described in paragraphs [0046] to [0049] of the specification of International publication No. 2014/171388.

In the case of identifying the components of the fiber treatment agent contained in the nonwoven fabric of the present invention, the surface tension (γ) of the liquid film (liquid having a surface tension of 50 mN/m) can be used_w) The method of identification described in the above-mentioned measurement method.

In the case where the component of the liquid film cracking agent is a compound having a siloxane chain in the main chain or a hydrocarbon compound having 1 to 20 carbon atoms, the content ratio (OPU) with respect to the mass of the fiber can be determined as follows: the content of the liquid film cracking agent was divided by the mass of the fiber based on the mass of the substance obtained by the above analysis method.

The nonwoven fabric of the present invention has high liquid permeability regardless of the thickness of the fibers or the distance between the fibers. However, the nonwoven fabric of the present invention is effective particularly in the case of using relatively fine fibers. When a nonwoven fabric having a soft texture is used, the distance between fibers is small and the narrow area between fibers is large. For example, in the case of a nonwoven fabric (fineness: 2.4dtex) which is usually used, the distance between fibers is 120 μm and the area ratio of the liquid film formed is about 2.6%. However, when the fineness was reduced to 1.2dtex, the distance between fibers was 85 μm, and the liquid film area ratio was about 7.8%, that is, about 3 times that of a normal nonwoven fabric. In contrast, the liquid film cracking agent of the present invention reliably cracks the liquid film that frequently occurs, thereby reducing the liquid residue. As described below, the liquid film area ratio is calculated by image analysis from the surface of the nonwoven fabric, and is closely related to the liquid remaining state on the outermost surface of the topsheet. Therefore, when the liquid film area ratio is decreased, the liquid in the vicinity of the skin is removed, and the comfort after excretion is improved, and the absorbent article has a good wearing feeling even after excretion. On the other hand, the liquid remaining amount described below means the amount of liquid held by the nonwoven fabric as a whole. If the liquid film area ratio is small, the liquid remains less although the liquid film area ratio is not proportional to the liquid film area ratio. The whiteness of the surface is represented by the following L value. The L value tends to be increased in value by a decrease in the residual amount of liquid due to the breakage of the liquid film on the surface, and whitening is easily noticeable visually. The nonwoven fabric containing the liquid film cleavage agent of the present invention can reduce the liquid film area ratio and the liquid residual amount and increase the L value even when the fibers are thinned, and therefore can achieve both a dry touch and a soft touch imparted by thinning the fibers at a high level. Further, by using the nonwoven fabric of the present invention as a constituent member such as a topsheet of an absorbent article, it is possible to provide an absorbent article having a high dry feeling at a portion in contact with the skin and less noticeable staining due to body fluid because the nonwoven fabric is visually whitish, and thus: the wearing feeling is good and the comfort is good.

In the nonwoven fabric containing the liquid film-splitting agent, the distance between fibers of the nonwoven fabric is preferably 150 μm or less, more preferably 90 μm or less, from the viewpoint of improving the softness to the touch of the skin. The lower limit is preferably 50 μm or more, and more preferably 70 μm or more, from the viewpoint of suppressing the deterioration of the liquid permeability due to the too narrow portion between the fibers. Specifically, it is preferably 50 μm or more and 150 μm or less, and more preferably 70 μm or more and 90 μm or less.

In this case, the fineness of the fibers is preferably 3.3dtex or less, more preferably 2.4dtex or less. The lower limit thereof is preferably 0.5dtex or more, more preferably 1.0dtex or more. Specifically, it is preferably 0.5dtex or more and 3.3dtex or less, and more preferably 1.0dtex or more and 2.4dtex or less.

(method of measuring distance between fibers)

The inter-fiber distance was determined from the following equation (Q2) by measuring the thickness of the nonwoven fabric to be measured.

First, a nonwoven fabric to be measured was cut into 50mm in the longitudinal direction × 50mm in the width direction to prepare cut pieces of the nonwoven fabric.

The thickness of the cut piece was measured under a pressure of 49 Pa. The measurement environment was a temperature of 20. + -. 2 ℃ and a relative humidity of 65. + -. 5%, and a microscope (VHX-1000, manufactured by KEYENCE K.K.) was used as a measuring instrument. First, an enlarged photograph of the cross section of the nonwoven fabric was obtained. The nonwoven of known dimensions is also shown in the magnified photograph. The thickness of the nonwoven fabric was measured by comparing the enlarged photograph of the cross section of the nonwoven fabric with a scale. The above operation was performed 3 times, and the average of the 3 times was defined as the thickness [ mm ] of the nonwoven fabric in a dry state. In the case of a laminate, the boundary is determined from the fiber diameter to calculate the thickness.

Then, the distance between fibers of the nonwoven fabric to be measured is determined by the following assumed formula based on Wrotnowski. The pseudo-equation system based on Wrotnowski is generally used for calculating the distance between fibers constituting a nonwoven fabric. According to the hypothesis based on Wrotnowski, the distance A (μm) between the fibers depends on the thickness h (mm) and the basis weight e (g/m) of the nonwoven fabric²) The fiber diameter d (. mu.m) of the fibers constituting the nonwoven fabric, and the fiber density ρ (g/cm)³) The calculation is performed by the following equation (Q2). When the nonwoven fabric has the unevenness, the nonwoven fabric thickness h (mm) of the unevenness is calculated as a representative value.

The fiber diameter d (. mu.m) was measured with respect to the fiber cross section of 10 cut fibers using a scanning electron microscope (DSC 6200 manufactured by Seiko Instruments Co., Ltd.), and the average value was defined as the fiber diameter.

Fiber density ρ (g/cm)³) The measurement was carried out by a density gradient tube method described in JIS L1015 chemical fiber short fiber test method.

With respect to basis weight e (g/m)²) The nonwoven fabric to be measured is cut into a predetermined size (0.12 × 0.06m, etc.), and after the mass measurement, the area obtained from the predetermined size is defined as the basis weight (g/m) ²) "was calculated to determine the basis weight.

[ mathematical formula 1]

Distance between fibres

(method of measuring fineness of constituent fiber)

The fiber cross-sectional shape is measured by an electron microscope or the like, the fiber cross-sectional area (in the case of a fiber made of a plurality of resins, the cross-sectional area of each resin component) is measured, the type of resin (in the case of a plurality of resins, the approximate component ratio is also determined) is determined by DSC (differential thermal analysis), and the specific gravity is calculated to calculate the fineness. For example, in the case of a short fiber composed of only PET (polyethylene terephthalate), the cross section is first observed and the cross section is calculated. Thereafter, the short fiber was identified to be composed of a single-component resin and to be a PET core from the melting point or peak shape by measurement with DSC. Then, the density and cross-sectional area of the PET resin were used to calculate the mass of the fiber, thereby calculating the fineness.

The fibers constituting the nonwoven fabric of the present invention may be those usually used for such articles, without any particular limitation. The nonwoven fabric of the present invention preferably contains a heat-fusible fiber from the viewpoint of imparting a gradient in hydrophilicity by the penetration of the component (a), the component (B), or the component (C) into the fiber. Specifically, there may be mentioned: various fibers such as heat-fusible core-sheath composite fibers, heat-extensible fibers, non-heat-extensible fibers, heat-shrinkable fibers, non-heat-shrinkable fibers, three-dimensional crimped fibers, latent crimped fibers, and hollow fibers. Particularly, it is preferable to have a thermoplastic resin. The core-sheath composite fiber may be a concentric core-sheath type, or an eccentric core-sheath type, or a side by side (side by side) type, or a profile type, and a concentric core-sheath type is preferable. In the production of the nonwoven fabric of the present invention, the adhesion of the fiber treatment agent of the present invention to the fibers of the nonwoven fabric may be carried out in any step. For example, the fiber treatment agent of the present invention can be blended with a spinning oil for fibers generally used in spinning fibers and applied; the fiber treatment agent of the present invention may be blended with a finishing oil for fibers before and after stretching of the fibers and applied. The fiber may be coated with a liquid film-splitting agent or a phosphate ester type anionic surfactant blended with a fiber treatment agent usually used for producing a nonwoven fabric, or may be coated after forming a nonwoven fabric. Further, the fiber treatment agent may be applied after forming into a nonwoven fabric.

The nonwoven fabric of the present invention is excellent in low liquid residue performance and low liquid return performance in response to various fiber structures because it contains the fiber treatment agent. Therefore, even if a large amount of liquid is applied to the nonwoven fabric, a liquid permeation path between the fibers is always ensured, the liquid permeability is excellent, and the liquid passing through is prevented from returning even when pressure or the like is applied. Thus, various functions can be imparted to the nonwoven fabric without being limited by the problem of the distance between fibers and the formation of a liquid film. For example, the film may include 1 layer, or may include 2 or more layers. The nonwoven fabric may have a flat shape, may have irregularities on one surface side or both surfaces, and may have various changes in basis weight and density of the fibers. Further, the nonwoven fabric of the present invention has excellent liquid permeability due to the action of the liquid film-splitting agent, and therefore the range of options for combination with the absorbent body is also expanded. Further, in the case where the nonwoven fabric of the present invention comprises a plurality of layers, the liquid film-cracking agent may be contained in all the layers or may be contained in a part of the layers. Preferably at least in the layer on the side directly receiving the liquid. For example, when the nonwoven fabric of the present invention is used as a topsheet of an absorbent article, it is preferable that the liquid film-splitting agent is contained in at least a layer on the skin contact surface side.

In addition, in the production of the nonwoven fabric of the present invention, a method generally used for such an article can be employed. For example, a carding method, an air-laid method, a spun-bond method, or the like can be used as a method for forming a web. As a method for forming a nonwoven fabric of a fiber web, various nonwoven fabric forming methods generally used, such as a spunlace method, a needle punching method, chemical bonding, and dot embossing, can be used. Among them, from the viewpoint of skin touch, a hot air nonwoven fabric and a spunbond nonwoven fabric are preferable. The "through-air nonwoven fabric" herein refers to a nonwoven fabric produced through a step (through-air treatment) of blowing a fluid of 50 ℃ or higher, for example, a gas or water vapor, onto a web or a nonwoven fabric. The term "spunbonded nonwoven fabric" refers to a laminated nonwoven fabric produced by the spunbonding method. The term "nonwoven fabric" refers not only to a nonwoven fabric produced by this step, but also to a nonwoven fabric produced by adding this step to a nonwoven fabric produced by another method or a nonwoven fabric produced by performing some steps after this step. The nonwoven fabric of the present invention is not limited to a nonwoven fabric composed of only a through-air nonwoven fabric or a spunbond nonwoven fabric, and includes a nonwoven fabric obtained by combining a fiber sheet such as a through-air nonwoven fabric or a spunbond nonwoven fabric with another nonwoven fabric or a film material.

In the method for producing a nonwoven fabric of the present invention, when the fiber treatment agent of the present invention is applied after forming a nonwoven fabric as described above, there are included: a method for impregnating a raw material nonwoven fabric in a solution containing the fiber treatment agent. In addition, as other methods, there are listed: a method of applying the fiber treatment agent of the present invention to a raw material nonwoven fabric. Further, the fiber treatment agent of the present invention may contain a phosphate ester type anionic surfactant as described above. In this case, the content ratio of the liquid film cleavage agent to the phosphate ester type anionic surfactant is preferably as described above. In the fiber treatment agent of the present invention, a solvent which can suitably dissolve or disperse a liquid film-splitting agent having extremely low water solubility in a solvent and emulsify the solution so as to be easily applied to a nonwoven fabric can be used without particular limitation as the solvent. For example, as a solvent for dissolving the liquid film breaking agent, an organic solvent such as ethanol, methanol, acetone, hexane, or the like can be used, or when an emulsion is prepared, it is needless to say that water can be used as a solvent or a dispersion medium, and as an emulsifier used in the emulsification, there can be mentioned: various surfactants including alkyl phosphates, fatty acid amides, alkyl betaines, sodium alkyl sulfosuccinates, and the like. The raw material nonwoven fabric refers to a nonwoven fabric before being coated with the liquid film cleavage agent, and the above-described generally used production method can be used without particular limitation as the production method.

The method for applying the coating to the raw material nonwoven fabric is not particularly limited, and a method for producing the nonwoven fabric can be used. Examples thereof include: coating by spraying, coating by a slit coater, coating by a gravure method, a flexographic method, a dip method, and the like.

In addition, as the raw material nonwoven fabric, various nonwoven fabrics can be used without particular limitation.

The fiber treatment agent of the present invention is a state in which the above-mentioned components, particularly the oily liquid film cleavage agent having extremely low water solubility, are easily applied to a raw material nonwoven fabric or fiber. In the fiber treatment agent of the present invention, the content ratio of the liquid film-splitting agent is preferably 50% by mass or less with respect to the mass of the fiber treatment agent. Thus, the fiber treatment agent can be in a state in which the liquid film breaking agent that is an oily component is stably emulsified in the solvent. From the viewpoint of stable emulsification, the content of the liquid film-splitting agent is more preferably less than 40% by mass, and still more preferably 30% by mass or less, based on the mass of the fiber-treating agent. The content ratio of the liquid film breaking agent is preferably 5% by mass or more, more preferably 15% by mass or more, and still more preferably 25% by mass or more relative to the mass of the fiber treatment agent, from the viewpoint of exhibiting a sufficient liquid film breaking effect. The fiber-treating agent of the present invention may contain other agents within the range not inhibiting the above-mentioned action of the liquid film-splitting agent and components (a) to (C). For example, the above-mentioned phosphate ester type anionic surfactant may be contained. In this case, the content ratio of the liquid film cleavage agent to the phosphate ester type anionic surfactant is preferably as described above. In addition, an antistatic agent or an anti-friction agent used in fiber processing, a hydrophilizing agent for imparting appropriate hydrophilicity to a nonwoven fabric, an emulsifier for imparting emulsion stability, and the like may be contained.

The heat-fusible fiber used in the present invention is preferably formed of a polyolefin resin at least on the surface. When the surface of the heat-fusible fiber, which is a constituent fiber of the nonwoven fabric, is formed of the polyolefin resin, the fiber surface is melted by heat treatment at the time of manufacturing the nonwoven fabric, and the fiber treatment agent is easily permeated into the fiber, thereby exhibiting an effect that the hydrophilicity of a desired portion can be efficiently reduced. Examples of the polyolefin resin forming the surface of the heat-fusible fiber include polyethylene and polypropylene, and 1 of these resins may be used alone or 2 or more of them may be mixed.

As the heat-fusible fiber, various fibers can be used which do not inhibit the penetration of the components in the fiber treatment agent into the fiber. Examples thereof include: "having an Inclusion" described in Japanese patent laid-open No. 2010-168715A sheath portion of a polyethylene resin, and a core-sheath type composite fiber (hereinafter, this fiber is referred to as a core-sheath type composite fiber S) "including a core portion having a melting point higher than that of a resin component of the polyethylene resin. Examples of the polyethylene resin constituting the sheath portion of the core-sheath composite fiber S include: low Density Polyethylene (LDPE), High Density Polyethylene (HDPE), straight-chain low density polyethylene (LLDPE), etc., preferably having a density of 0.935g/cm ³Above and 0.965g/cm³The following high density polyethylene. The resin component constituting the sheath portion of the core-sheath composite fiber S is preferably a polyethylene resin alone. However, the present invention is not limited thereto, and various methods can be employed.

The sheath portion of the core-sheath type composite fiber S plays a role as follows: the fiber treatment agent is introduced into the heat treatment process while the heat-fusible core-sheath composite fiber is provided with heat-fusible properties. This promotes penetration of the components in the fiber treatment agent into the fibers, and facilitates formation of a hydrophilization gradient in the surface sheet. However, the heat-fusible fiber used for the surface sheet is not limited to the core-sheath composite fiber S. For example, the sheath portion may be polypropylene (PP), copolyester, or the like, corresponding to the resin component of the core portion.

On the other hand, the core portion is a portion that imparts strength to the heat-fusible core-sheath composite fiber. As the resin component constituting the core portion of the core-sheath composite fiber S, a resin component having a melting point higher than that of the polyethylene resin as the constituent resin of the sheath portion can be used without particular limitation. Examples of the resin component constituting the core include: polyolefin resins (other than polyethylene resins) such as polypropylene (PP), and polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT).

In the heat-fusible core-sheath composite fiber to which the fiber treatment agent is attached, in terms of ease of production of the nonwoven fabric, the difference between the melting point of the resin component constituting the core part and the melting point of the resin component constituting the sheath part (the former-the latter) is preferably 20 ℃ or more, and further preferably 150 ℃ or less. When the resin component constituting the core is a blend of a plurality of resins, the melting point of the resin having the highest melting point is used.

The heat-fusible fiber is preferably a fiber whose length is stretched by heating (hereinafter, also referred to as a heat-extensible fiber). Examples of the heat-extensible fiber include: the fibers spontaneously stretch as the crystalline state of the resin changes by heating. The heat-extensible fibers are present in the nonwoven fabric in a state in which the length thereof is extended by heating, or in a state in which both are extended by heating. The fiber treatment agent on the surface of the heat-extensible fiber is likely to penetrate into the inside during heating, and a plurality of portions having a large difference in hydrophilicity due to the heat treatment are likely to be formed in the fiber or a nonwoven fabric produced using the fiber.

The preferred thermally extensible fiber is a conjugate fiber (hereinafter, also referred to as a thermally extensible conjugate fiber) having a 1 st resin component constituting the core portion and a 2 nd resin component constituting the sheath portion. The 2 nd resin component has a lower melting point or softening point than the 1 st resin component and is continuously present on at least a part of the fiber surface in the longitudinal direction. The 1 st resin component is a component showing thermal extensibility of the fiber, and the 2 nd resin component is a component showing thermal fusion.

The melting points of the 1 st resin component and the 2 nd resin component are defined as temperatures measured by the following method using a differential scanning calorimeter (DSC 6200 manufactured by Seiko Instruments Co., Ltd.). That is, thermal analysis of the finely cut fiber sample (sample mass: 2mg) was performed at a temperature increase rate of 10 ℃/min, and the melting peak temperature of each resin was measured and defined. In the case where the melting point of the 2 nd resin component cannot be clearly measured by this method, this resin is defined as a "resin having no melting point". In this case, as the temperature at which the molecular flow of the 2 nd resin component starts, a temperature at which the 2 nd resin component fuses to a degree that the fusion point strength of the fiber can be measured is set as a softening point, and is used instead of the melting point.

The thermally extensible composite fiber may be thermally extended at a temperature lower than the melting point of the 1 st resin component. The thermal elongation of the thermally extensible conjugate fiber is preferably 0.5% to 20%, more preferably 3% to 20%, and still more preferably 5.0% to 20% at a temperature higher by 10 ℃ than the melting point of the 2 nd resin component (softening point in the case of a resin having no melting point). A nonwoven fabric including such a fiber having thermal elongation is bulky by elongation of the fiber, or exhibits a three-dimensional appearance. The thermal elongation of the fiber is determined by the method described in paragraphs [0031] to [0032] of Japanese patent application laid-open No. 2010-168715.

The fiber diameter of the thermally extensible composite fiber is appropriately selected depending on the specific use of the nonwoven fabric. When a nonwoven fabric is used as a component of an absorbent article such as a topsheet of an absorbent article, it is preferable to use a fiber having a fiber diameter of 10 μm or more and 35 μm or less, particularly 15 μm or more and 30 μm or less. When the fiber diameter of the thermally extensible conjugate fiber is reduced by elongation, the fiber diameter described above refers to the fiber diameter when the nonwoven fabric is actually used.

As the thermally expandable conjugate fiber, in addition to the above-mentioned thermally expandable conjugate fiber, fibers described in Japanese patent No. 4131852, Japanese patent No. 2005-350836, Japanese patent No. 2007-303035, Japanese patent No. 2007-204899, Japanese patent No. 2007-204901, and Japanese patent No. 2007-204902 can be used.

As described above, a nonwoven fabric having a plurality of portions with different degrees of hydrophilicity can be obtained by subjecting a web or a nonwoven fabric produced using heat-fusible fibers to heat treatment.

The heat-fusible fiber preferably has a contact angle of water with respect to a fiber taken out of the nonwoven fabric of 90 degrees or less. The fibers having a surface with a further increased hydrophilicity by the fiber treatment agent can form a plurality of regions having a large difference in hydrophilicity in the fibers themselves or in a nonwoven fabric or the like produced using the fibers. From the same viewpoint, the contact angle of the heat-fusible core-sheath composite fiber taken out from the nonwoven fabric with water is preferably 90 degrees or less, more preferably 85 degrees or less, and if the hydrophilicity is too high, the liquid is easily held, so that it is preferably 60 degrees or more, more preferably 65 degrees or more. Further, it is preferably 65 degrees or more and 85 degrees or less, and more preferably 70 degrees or more and 80 degrees or less. The decrease in hydrophilicity is synonymous with an increase in contact angle. The contact angle can be obtained by the following measurement method.

(method of measuring contact Angle)

The contact angle can be measured by the following method.

That is, a fiber is taken out from a specific portion of the nonwoven fabric, and the contact angle of water with respect to the fiber is measured. An automatic contact angle meter MCA-J manufactured by Kyowa Kagaku K.K. was used as a measuring apparatus. Distilled water was used for the measurement of the contact angle. The measurement was carried out under conditions of a temperature of 25 ℃ and a Relative Humidity (RH) of 65%. The amount of liquid discharged from an inkjet type water droplet discharge unit (pulse jet CTC-25 having a discharge unit aperture of 25 μm, manufactured by Cluster Technology) was set to 20 picoliters, and water droplets were dropped directly onto the fibers. The dripping state is recorded in a high-speed recording device connected to a horizontally arranged camera. In the video recorder, a personal computer equipped with a high-speed capture device is preferable from the viewpoint of performing image analysis thereafter. In this measurement, images were recorded every 17 msec. In the recorded image, the initial image of the fiber taken out from the nonwoven fabric was subjected to image analysis using the satellite software FAMAS (assuming that the version of the software is 2.6.2, the analysis technique is the liquid drop method, the analysis method is the θ/2 method, the image processing algorithm is no reflection, the image processing image mode is the frame, the threshold level is 200, and no curvature correction was performed), and the angle formed by the surface of the water drop in contact with the air and the fiber was calculated, and the contact angle was defined. The fiber taken out of the nonwoven fabric was cut to a fiber length of 1mm, and the fiber was placed on a sample stage of a contact angle meter and maintained horizontally. The contact angle was measured at 2 different sites for each of the fibers. The contact angle was measured until the contact angle was 1 decimal point or less, and the value obtained by averaging the measured values of 10 total positions (rounded at the 2 nd position or less) was defined as the contact angle.

(preferred embodiment of the gradient of hydrophilicity in the nonwoven fabric of the invention)

The nonwoven fabric of the present invention may have a single-layer structure or a multilayer structure in which two or more layers are laminated. Examples of the nonwoven fabric having a multilayer structure of the present invention include the following: the fibers having the 1 st layer and the 2 nd layer adjacent thereto and containing the fiber treatment agent of the present invention adhered to at least one of the 1 st layer and the 2 nd layer include, more specifically: the nonwoven fabric satisfying the following condition I or II, preferably a through-air nonwoven fabric. Under the following conditions I and II, the 1 st layer and the 2 nd layer are adjacent to and in direct contact with each other, and no other layer is present between the two layers. The 1 st layer and the 2 nd layer are distinguished depending on the type of fiber material constituting these layers, the thickness of the fiber, the presence or absence of hydrophilization treatment, the method of forming the layers, and the like. When the cross section of the nonwoven fabric having a multilayer structure of the present invention in the thickness direction is enlarged by an electron microscope, the boundary portion between the two layers due to the above-mentioned factors can be observed. The nonwoven fabric satisfying the following condition I or II may have the 1 st layer side as the use surface, or may have the 2 nd layer side as the use surface, and the side to be used may be determined depending on the specific use of the nonwoven fabric. (Condition I)

When the 1 st layer is virtually bisected in the thickness direction thereof, and the portion farther from the 2 nd layer among the 2 bisected portions is the 1 st layer 1 st portion, and the portion closer to the 2 nd layer is the 1 st layer 2 nd portion, the fiber-treating agent of the present invention satisfies the following relationships (11) and (12) when the degrees of hydrophilicity of the 1 st layer 1 st portion, the 1 st layer 2 nd portion, and the 2 nd layer are compared.

(11) The 2 nd site of layer 1 has a higher degree of hydrophilicity than the 1 st site of layer 1.

(12) The hydrophilicity of any portion in layer 2 is higher than the hydrophilicity of layer 1 at portion 2.

The nonwoven fabric satisfying the above condition I has the following relationship in magnitude of the degrees of hydrophilicity of the 1 st part of the 1 st layer, the 2 nd part of the 1 st layer, and the 2 nd layer: any part of the 1 st layer < the 2 nd layer. The term "any site in the 2 nd layer" means a site having the highest degree of hydrophilicity among the degrees of hydrophilicity measured in the thickness direction of the 2 nd layer. The same applies to the 1 st part and the 1 st 2 nd part of the 1 st layer, and the hydrophilicity of the 1 st part and the 1 st 2 nd part of the 1 st layer is the hydrophilicity of the part exhibiting the highest hydrophilicity when the hydrophilicity is measured in the thickness direction of these parts. The "degree of hydrophilicity" in the present invention is determined based on the contact angle of the fiber with water measured by the above method. Specifically, the case of low hydrophilicity is synonymous with the case of large contact angle, and the case of high hydrophilicity is synonymous with the case of small contact angle.

Since the nonwoven fabric satisfying the condition I is provided with the hydrophilicity gradient defined in the above (11) and (12) in the thickness direction thereof, when a liquid is supplied to the 1 st layer side, the liquid rapidly permeates through the nonwoven fabric. Therefore, on the surface on the 1 st layer side, the liquid becomes difficult to flow on the surface. As a result, it becomes difficult to leave the liquid on the surface on the 1 st layer side, which is the surface to which the liquid is supplied. These remarkable effects are particularly remarkable when the nonwoven fabric satisfying the above condition I is used as a topsheet of an absorbent article so that the surface on the 1 st layer side is a skin-facing surface.

(Condition II)

When the 2 nd layer is virtually bisected in the thickness direction thereof, and a portion closer to the 1 st layer among the 2 bisected portions is defined as the 1 st portion of the 2 nd layer, and a portion farther from the 1 st layer is defined as the 2 nd portion of the 2 nd layer, the fiber-treating agent of the present invention satisfies the following relationships (21) and (22) when the degrees of hydrophilicity of the 1 st layer, the 1 nd portion of the 2 nd layer, and the 2 nd portion of the 2 nd layer are compared.

(21) The layer 2 has a higher degree of hydrophilicity at the 1 st site than at the 1 st layer.

(22) The 2 nd site of layer 2 has a higher degree of hydrophilicity than the 1 st site of layer 2.

In the nonwoven fabric satisfying the above condition II, when the relationship of the degrees of hydrophilicity of the 1 st layer, the 2 nd layer, the 1 st portion, and the 2 nd layer, the 2 nd portion becomes the 1 st layer < the 2 nd layer, the 1 st portion < the 2 nd layer, the 2 nd portion as defined in the above (21) and (22), since such a hydrophilicity gradient is provided in the thickness direction, if a liquid is supplied to the 1 st layer side, the liquid rapidly permeates through the nonwoven fabric. Therefore, on the surface on the 1 st layer side, the liquid becomes difficult to flow on the surface. As a result, it becomes difficult to leave the liquid on the surface on the 1 st layer side, which is the surface to which the liquid is supplied. Moreover, the liquid that has once passed through the nonwoven fabric satisfying the above condition II becomes difficult to return to the liquid. These remarkable effects are particularly remarkable when the nonwoven fabric satisfying the above condition II is used as a topsheet of an absorbent article so that the surface on the 1 st layer side is a skin-facing surface.

FIGS. 3 to 5 show various preferred embodiments of the nonwoven fabric having the hydrophilicity gradient under the condition I. The following describes the form of the nonwoven fabric shown in each of FIGS. 3 to 5.

The nonwoven fabric 100 shown in fig. 3 is a through-air (airfrough) nonwoven fabric, and has a 1 st layer 130 and a 2 nd layer 140. Layer 1 130 is in direct contact with layer 2 140 and no other layers are present between the two layers. The 1 st layer 130 and the 2 nd layer 140 are each a single fiber layer, and are not formed of a further subdivided multilayer laminate. The 1 st layer 130 and the 2 nd layer 140 are bonded to each other over the entire regions of the facing surfaces, and no gap is formed between the two

layers

130 and 140. In fig. 5, the 1 st layer 130 and the 2 nd layer 140 are shown to have the same thickness, but the

layers

130 and 140 are schematically shown, so that the thicknesses of the 1 st layer 130 and the 2 nd layer 140 may be different in the actual nonwoven fabric 100.

Both the 1 st layer 130 and the 2 nd layer 140 are composed of fibers randomly stacked. The fibers constituting the 1 st layer 130 are fused at the intersections of the fibers by hot air. The same is true for layer 2 140. At the boundary between the 1 st layer 130 and the 2 nd layer 140, the fibers constituting the 1 st layer 130 and the fibers constituting the 2 nd layer 140 are fused at their intersections by hot air. Additionally, the fibers forming the 1 st layer 130 may be bonded by a method other than hot air fusion. For example, the complementary bonding may be performed by fusion by hot embossing, winding by a high-pressure jet, or adhesion by an adhesive. The same applies to the 2 nd layer 140, and also to the boundary between the 1 st layer 130 and the 2 nd layer 140.

In this specification, when the 1 st layer 130 composed of a single layer is virtually bisected in the thickness direction, a portion of the 2 nd bisected portions on the side farther from the 2 nd layer 140 is referred to as a 1 st layer 1 portion 131, and a portion closer to the 2 nd layer 140 is referred to as a 1 st layer 2 portion 132. Since the 1 st layer 130 is formed of a single layer, no boundary exists between the 1 st portion 131 and the 2 nd portion 132. The fibers constituting the 1 st portion 131 are the same as those constituting the 2 nd portion 132.

In the 1 st layer 130 of the nonwoven fabric 100 shown in fig. 3, the 2 nd site 132 has a higher degree of hydrophilicity than the 1 st site 131. In order to provide such a gradient in hydrophilicity in the 1 st layer 130, it is preferable that the 1 st layer 130 contains the fibers to which the fiber treatment agent of the present invention is attached. In this case, the degree of hydrophilicity of the 1 st layer 130 may be gradually increased from the 1 st portion 131 to the 2 nd portion 132, or the degree of hydrophilicity may be gradually increased from the 1 st portion 131 to the 2 nd portion 132. From the viewpoint of improving the liquid permeability in the thickness direction, the hydrophilicity is preferably gradually increased from the 1 st portion 131 to the 2 nd portion 132. From the viewpoint of providing a gradient of the degree of hydrophilicity which gradually increases in the degree of hydrophilicity, it is also preferable that the 1 st layer 130 contains a heat-fusible fiber to which the fiber treatment agent is attached.

In the 1 st layer 130, the contact angle of water with respect to the fibers included in the 1 st portion 131 of the 1 st layer is preferably 70 degrees or more, particularly 72 degrees or more, regardless of whether the degree of hydrophilicity is gradually increased or the degree of hydrophilicity is increased stepwise. Further, it is preferably 85 degrees or less, particularly 82 degrees or less. For example, the contact angle of water with respect to the fibers included in the 1 st portion 131 of the 1 st layer is preferably 70 degrees or more and 85 degrees or less, and preferably 72 degrees or more and 82 degrees or less. On the other hand, the contact angle of water with respect to the fibers included in the 1 st part 132 is set to be smaller than the contact angle of water with respect to the fibers included in the 1 st part 131 of the 1 st layer, and is preferably 60 degrees or more, particularly 65 degrees or more. Further, it is preferably 80 degrees or less, particularly 75 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd site 132 of the 1 st layer is preferably 60 degrees or more and 80 degrees or less, and preferably 65 degrees or more and 75 degrees or less.

In contrast to the layer 1 130 having a gradient in hydrophilicity, in the present embodiment shown in fig. 3, the hydrophilicity of the layer 2 140 is the same at any portion of the layer 2 140. The hydrophilicity of the layer 2 140 becomes higher than the hydrophilicity of the layer 1, the 2 nd site 132. As described above, the nonwoven fabric 100 of the embodiment shown in fig. 3 has a higher degree of hydrophilicity in the order of the 1 st layer 1 st portion 131, the 1 st layer 2 nd portion 132, and the 2 nd layer 140. The contact angle of water with respect to the fibers included in the 2 nd layer 140 is set on the condition that the contact angle is smaller than the contact angle of water with respect to the fibers included in the 1 st portion 132 of the 1 st layer, and is preferably 20 degrees or more, particularly 30 degrees or more, and preferably 75 degrees or less, particularly 65 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd layer 140 is preferably 20 degrees or more and 75 degrees or less, and preferably 30 degrees or more and 65 degrees or less.

In the nonwoven fabric 100 shown in fig. 3, the hydrophilicity of the 2 nd layer 140 is the same at any position as described above, and in this case, in order to form such a 2 nd layer 140, for example, a conventionally used agent called a finish agent for imparting hydrophilicity to fibers may be used. For example, the above anionic, cationic, amphoteric and nonionic surfactants can be used. The constituent fibers of the 2 nd layer 40 are preferably not treated with any of the components (a) to (C) described above. At this time, the liquid film cracking agent is preferably attached to at least the 1 st layer 130, and more preferably attached to the 2 nd layer 140 in addition to the 1 st layer 130.

In the nonwoven fabric 100 shown in fig. 3, from the viewpoint of allowing liquid to further smoothly permeate from the 1 st layer 130 to the 2 nd layer 140, the difference between the contact angle of water with respect to the fibers contained in the 2 nd part 132 of the 1 st layer and the contact angle of water with respect to the fibers contained in the 2 nd layer 140 (the 1 st layer 2 nd part 132 to the 2 nd layer 140) is preferably 1 degree or more, particularly 10 degrees or more, further 20 degrees or more, and preferably 50 degrees or less, particularly 40 degrees or less. For example, the difference is preferably 1 degree or more and 50 degrees or less, and more preferably 10 degrees or more and 40 degrees or less.

From the same viewpoint as described above, in the nonwoven fabric 100 shown in fig. 3, the difference between the contact angle of water with respect to the fibers contained in the 1 st part 131 of the 1 st layer and the contact angle of water with respect to the fibers contained in the 2 nd layer 140 (the 1 st part 131 of the 1 st layer to the 2 nd layer 140) is preferably 2 degrees or more, particularly 10 degrees or more, further 20 degrees or more, and further preferably 65 degrees or less, particularly 50 degrees or less, provided that the difference is larger than the difference between the contact angles of the 2 nd part 132 of the 1 st layer to the 2 nd layer 140. For example, the difference is preferably 2 degrees or more and 65 degrees or less, and more preferably 10 degrees or more and 50 degrees or less.

The nonwoven fabric 101 shown in fig. 4 and the nonwoven fabric 102 shown in fig. 5 are both nonwoven fabrics (air-through nonwoven fabrics) satisfying the above condition I. These

nonwoven fabrics

101 and 102 are different from the nonwoven fabric 100 described above, and the description of the nonwoven fabric 100 is appropriately applied, although the same points are not particularly described. In fig. 4 and 5, the same components as those in fig. 3 are denoted by the same reference numerals.

In the nonwoven fabric 101 shown in fig. 4, the 1 st layer 130 has the same configuration as the 1 st layer 130 of the nonwoven fabric 100 shown in fig. 3. On the other hand, when the 2 nd layer 140 of the nonwoven fabric 101 is virtually bisected in the thickness direction thereof, a portion closer to the 1 st layer 130 among the 2 bisected portions is referred to as a 2 nd layer 1 st portion 141, and a portion farther from the 1 st layer 130 is referred to as a 2 nd layer 2 nd portion 142. Since the 2 nd layer 140 is formed of a single layer, there is no boundary between the 1 st portion 141 and the 2 nd portion 142. The fibers constituting the 1 st portion 141 are the same as the fibers constituting the 2 nd portion 142.

In the nonwoven fabric 101 shown in fig. 4, when the degrees of hydrophilicity of the 1 st layer 1 st portion 131, the 1 st layer 2 nd portion 132, the 2 nd layer 1 st portion 141, and the 2 nd layer 2 nd portion 142 are compared, the following relationships (13) and (14) are satisfied in addition to the relationship (11) described above, that is, the relationship (13) in which the degree of hydrophilicity of the 1 st layer 2 nd portion 132 is higher than that of the 1 st layer 1 st portion 131.

(13) The layer 2, layer 1 site 141 is more hydrophilic than the layer 1, layer 2, site 132.

(14) The layer 2, site 142 has a higher degree of hydrophilicity than the layer 2, site 141.

As described above, the nonwoven fabric 101 shown in fig. 4 has a gradient in the degree of hydrophilicity in the 1 st layer 130, and the 2 nd layer 140 also has a gradient in the degree of hydrophilicity. The degree of hydrophilicity is in the range of layer 1, part 1 131 < layer 1, part 2 132 < layer 2, part 1 141 < layer 2, part 142. In this case, similarly to the 1 st layer 130 of the nonwoven fabric 101, the 2 nd layer 140 may have a degree of hydrophilicity gradually increasing from the 1 st portion 141 to the 2 nd portion 142, or may have a degree of hydrophilicity gradually increasing from the 1 st portion 141 to the 2 nd portion 142. From the viewpoint of improving the liquid permeability in the thickness direction, the hydrophilicity is preferably gradually increased from the 1 st site 141 to the 2 nd site 142. From the viewpoint of providing a hydrophilicity gradient in which the degree of hydrophilicity gradually increases, the fiber to which the fiber treatment agent of the present invention described above is attached is preferably contained not only in the 1 st layer 130 but also in the 2 nd layer 140.

In the 1 st layer 130 of the nonwoven fabric 101 shown in fig. 4, the contact angle of water with respect to the fibers included in the 1 st portion 131 of the 1 st layer is preferably 70 degrees or more, particularly 72 degrees or more. Further, it is preferably 85 degrees or less, particularly 82 degrees or less. For example, the contact angle of water with respect to the fibers included in the 1 st portion 131 of the 1 st layer is preferably 70 degrees or more and 85 degrees or less, and preferably 72 degrees or more and 82 degrees or less. On the other hand, the contact angle of water with respect to the fibers included in the 1 st part 132 of the layer is preferably 60 degrees or more, particularly 65 degrees or more, provided that the contact angle is smaller than the contact angle of water with respect to the fibers included in the 1 st part 131 of the layer 1. Further, it is preferably 80 degrees or less, particularly 75 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd site 132 of the 1 st layer is preferably 60 degrees or more and 80 degrees or less, and preferably 65 degrees or more and 75 degrees or less.

In the 2 nd layer 140 of the nonwoven fabric 101 shown in fig. 4, the contact angle of water with respect to the fibers included in the 1 st portion 141 of the 2 nd layer is preferably 50 degrees or more, particularly 55 degrees or more. Further, it is preferably 75 degrees or less, particularly 70 degrees or less. For example, the contact angle of water with respect to the fibers included in the 1 st portion 141 of the 2 nd layer is preferably 50 degrees or more and 75 degrees or less, and preferably 55 degrees or more and 70 degrees or less. On the other hand, the contact angle of water with respect to the fibers included in the 2 nd part 142 of the 2 nd layer is preferably 20 degrees or more, particularly 30 degrees or more, under the condition that the contact angle is smaller than the contact angle of water with respect to the fibers included in the 1 st part 141 of the 2 nd layer. Further, it is preferably 70 degrees or less, particularly 65 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd portion 142 of the 2 nd layer is preferably 20 degrees or more and 70 degrees or less, and preferably 30 degrees or more and 65 degrees or less.

In the nonwoven fabric 101 shown in fig. 4, from the viewpoint of allowing liquid to further smoothly permeate from the 1 st layer 130 to the 2 nd layer 140, the difference between the contact angle of water with respect to the fibers contained in the 2 nd part 132 of the 1 st layer and the contact angle of water with respect to the fibers contained in the 1 st part 141 of the 2 nd layer (the 1 st layer 2 nd part 132-the 2 nd layer 1 st part 141) is preferably 1 degree or more, particularly 10 degrees or more, and preferably 30 degrees or less, particularly 25 degrees or less. For example, the difference is preferably 1 degree or more and 30 degrees or less, and more preferably 10 degrees or more and 25 degrees or less.

From the same viewpoint as described above, in the nonwoven fabric 101 shown in fig. 4, the difference between the contact angle of water with respect to the fibers contained in the 1 st part 131 of the 1 st layer and the contact angle of water with respect to the fibers contained in the 2 nd part 142 of the 2 nd layer (the 1 st part 131 of the 1 st layer to the 2 nd part 142 of the 2 nd layer) is greater than the difference between the contact angles of the 2 nd part 132 of the 1 st layer and the 1 st part 141 of the 2 nd layer, and is preferably 2 degrees or more, particularly 10 degrees or more, and preferably 65 degrees or less, particularly 50 degrees or less. For example, the difference is preferably 2 degrees or more and 65 degrees or less, and more preferably 10 degrees or more and 50 degrees or less.

The nonwoven fabric 101 shown in fig. 4 exhibits the same effects as the nonwoven fabric 100 shown in fig. 3. Since the nonwoven fabric 101 has a gradient in hydrophilicity in the 2 nd layer 140, the effect exerted by the nonwoven fabric 100 becomes more remarkable.

In the nonwoven fabric 102 shown in fig. 5, similarly to the nonwoven fabric 101 shown in fig. 4, the 1 st layer 130 has a gradient in hydrophilicity, and the 2 nd layer 140 has a gradient in hydrophilicity. In addition, in the 1 st layer 130, similarly to the nonwoven fabric 101, the degree of hydrophilicity of the 2 nd site 133 is higher than that of the 1 st site 131, and the degrees of hydrophilicity of the 2 nd layer 140 and the 2 nd site 142 are higher than that of the 1 st site 143. In the nonwoven fabric 102 shown in fig. 5, the nonwoven fabric 101 shown in fig. 4 is different from the nonwoven fabric 102 shown in fig. 5 in that the relationship of the degree of hydrophilicity is 1 st portion 131 < 2 nd portion 143 < 1 st portion 133 < 2 nd portion 142 of the layer 1. Except for this point, the nonwoven fabric is the same as the nonwoven fabric 101 shown in fig. 4.

In short, the nonwoven fabric 102 shown in fig. 5 is a hot-air nonwoven fabric satisfying the following relationships (15), (16) and (17) in addition to the relationship (11) described above, that is, the hydrophilicity of the 1 st layer 2 nd portion 133 is higher than the hydrophilicity of the 1 st layer 1 st portion 131.

(15) Layer 2, site 1 143 has a higher degree of hydrophilicity than layer 1, site 1 131.

(16) Layer 1, location 2 133 is more hydrophilic than layer 2, location 1 143.

(17) The layer 2, location 2 142 is more hydrophilic than the layer 1, location 2 133.

As described above, unlike the

nonwoven fabrics

100 and 101 described above, the nonwoven fabric 102 shown in fig. 5 does not have a hydrophilicity that gradually increases from the 1 st layer 130 side toward the 2 nd layer 140 side, but the relationship between the hydrophilicity at the 1 st layer 2 nd site 133 and the hydrophilicity at the 2 nd layer 1 st site 143 is reversed. The nonwoven fabric 102 having such a relationship of hydrophilicity exhibits the same effects as those of the

nonwoven fabrics

100 and 101 shown in fig. 3 and 4 described above, respectively, and also exhibits an effect that the liquid once having passed through the nonwoven fabric 102 is further made difficult to flow back because the relationship of the hydrophilicity is reversed between the 1 st layer 2 nd portion 133 and the 2 nd layer 1 st portion 143; and allowing the liquid to permeate the nonwoven fabric 102 while diffusing the liquid in the plane direction of the nonwoven fabric 102. The effect of further making it difficult for the liquid to flow back is advantageous in that, when the nonwoven fabric 102 is used as a topsheet of an absorbent article, the liquid temporarily absorbed by the absorbent body is made difficult to flow back even when the body pressure of the wearer is applied. Further, the effect of diffusing and transmitting the liquid in the planar direction of the nonwoven fabric 102 is advantageous in that, when the nonwoven fabric 102 is used as a topsheet of an absorbent article, the liquid can be absorbed in all the portions in the planar direction of the absorbent body, and the absorption performance of the absorbent body can be effectively utilized.

In the 1 st layer 130 of the nonwoven fabric 102 shown in fig. 5, the contact angle of water with respect to the fibers included in the 1 st portion 131 of the 1 st layer is preferably 70 degrees or more, particularly 72 degrees or more. Further, it is preferably 85 degrees or less, particularly 82 degrees or less. For example, the contact angle of water with respect to the fibers included in the 1 st portion 131 of the 1 st layer is preferably 70 degrees or more and 85 degrees or less, and preferably 72 degrees or more and 82 degrees or less. On the other hand, the contact angle of water with respect to the fibers included in the 2 nd site 133 of the 1 st layer is preferably 50 degrees or more, particularly 55 degrees or more, under the condition that the contact angle is smaller than the contact angle of water with respect to the fibers included in the 1 st site 131 of the 1 st layer. Further, it is preferably 75 degrees or less, particularly 70 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd site 133 of the 1 st layer is preferably 50 degrees or more and 75 degrees or less, and preferably 55 degrees or more and 70 degrees or less.

In the 2 nd layer 140 of the nonwoven fabric 102 shown in fig. 5, the contact angle of water with respect to the fibers included in the 1 st site 143 of the 2 nd layer is preferably 60 degrees or more, particularly 65 degrees or more. Further, it is preferably 80 degrees or less, particularly 75 degrees or less. For example, the contact angle of water with respect to the fibers included in the 1 st portion 143 of the layer 2 is preferably 60 degrees or more and 80 degrees or less, and preferably 65 degrees or more and 75 degrees or less. On the other hand, the contact angle of water with respect to the fibers included in the 2 nd part 142 of the 2 nd layer is preferably 30 degrees or more, particularly 40 degrees or more, under the condition that the contact angle is smaller than the contact angle of water with respect to the fibers included in the 1 st part 143 of the 2 nd layer. Further, it is preferably 70 degrees or less, particularly 65 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd portion 142 of the 2 nd layer is preferably 30 degrees or more and 70 degrees or less, and preferably 40 degrees or more and 65 degrees or less.

From the viewpoint of further improving the effect of making it difficult to reflow the liquid that has once passed through the nonwoven fabric 102 shown in fig. 5 and the effect of making the liquid pass through the nonwoven fabric 22A while diffusing the liquid in the planar direction of the nonwoven fabric 102, the difference between the contact angle of water with respect to the fibers contained in the 1 st portion 143 of the 2 nd layer and the contact angle of water with respect to the fibers contained in the 2 nd portion 133 of the 1 st layer (the 1 st portion 143 of the 2 nd layer to the 2 nd portion 133 of the 1 st layer) is preferably 1 degree or more, particularly 2 degrees or more, and preferably 30 degrees or less, particularly 25 degrees or less. For example, the difference is preferably 1 degree or more and 30 degrees or less, and more preferably 2 degrees or more and 25 degrees or less.

In the nonwoven fabric 102 shown in fig. 5, from the viewpoint of allowing a liquid to further smoothly permeate from the 1 st layer 130 to the 2 nd layer 140, the difference between the contact angle of water with respect to the fibers contained in the 1 st part 131 of the 1 st layer and the contact angle of water with respect to the fibers contained in the 2 nd part 142 of the 2 nd layer (the 1 st part 131 of the 1 st layer to the 2 nd part 142 of the 2 nd layer) is preferably 2 degrees or more, particularly 5 degrees or more, and preferably 55 degrees or less, particularly 45 degrees or less. For example, the difference is preferably 2 degrees or more and 55 degrees or less, and more preferably 5 degrees or more and 45 degrees or less.

In the 1 st layer 130 of the nonwoven fabric 102 shown in fig. 5, the degree of hydrophilicity may be gradually increased from the 1 st portion 131 to the 2 nd portion 133, or the degree of hydrophilicity may be gradually increased from the 1 st portion 131 to the 2 nd portion 133. On the other hand, in the 2 nd layer 140, the degree of hydrophilicity may be gradually increased from the 1 st portion 143 to the 2 nd portion 142, or the degree of hydrophilicity may be gradually increased from the 1 st portion 143 to the 2 nd portion 142.

On the other hand, fig. 6 shows a specific example of the nonwoven fabric satisfying the condition II. The nonwoven fabric 103 shown in fig. 6 is a through-air nonwoven fabric, and has a 1 st layer 130 and a 2 nd layer 140. The 1 st layer 130 is in direct contact with the 2 nd layer 140, and no other layer is present between the two layers. The 1 st layer 130 and the 2 nd layer 140 are each a single fiber layer, and are not formed of a further subdivided multilayer laminate. The 1 st layer 130 and the 2 nd layer 140 are bonded to each other over the entire regions of the facing surfaces, and no gap is formed between the two

layers

130 and 140. In fig. 6, the 1 st layer 130 and the 2 nd layer 140 are shown to have the same thickness, but the

layers

130 and 140 are schematically shown, and the thicknesses of the 1 st layer 130 and the 2 nd layer 140 may be different in the actual nonwoven fabric 103.

In the nonwoven fabric 103 shown in fig. 6, the 1 st layer 130 and the 2 nd layer 140 are both composed of fibers randomly stacked. The fibers constituting the 1 st layer 130 are fused at the intersections of the fibers by hot air. The same is true for layer 2 140. At the boundary between the 1 st layer 130 and the 2 nd layer 140, the fibers constituting the 1 st layer 130 and the fibers constituting the 2 nd layer 140 are fused at their intersections by hot air. Additionally, the fibers forming the 1 st layer 130 may be bonded by a method other than hot air fusion. For example, the complementary bonding may be performed by fusion by hot embossing, winding by a high-pressure jet, or adhesion by an adhesive. The same applies to the 2 nd layer 140, and also to the boundary between the 1 st layer 130 and the 2 nd layer 140.

In this specification, when the 2 nd layer 140 composed of a single layer is virtually bisected in the thickness direction, a portion closer to the 1 st layer 130 among the 2 bisected portions is referred to as a 2 nd layer 1 st portion 141, and a portion farther from the 1 st layer 130 is referred to as a 2 nd layer 2 nd portion 142. Since the 2 nd layer 140 is formed of a single layer, there is no boundary between the 2 nd site 141 and the 2 nd site 142. The fibers constituting the 1 st portion 141 are the same as the fibers constituting the 2 nd portion 142.

In the 2 nd layer 140 of the nonwoven fabric 103 shown in fig. 6, the 2 nd site 142 has a higher degree of hydrophilicity than the 1 st site 141. In order to provide such a gradient in hydrophilicity in the 2 nd layer 140, it is preferable that the 2 nd layer 140 contains the fibers to which the fiber treatment agent of the present invention described above is attached. In this case, the 2 nd layer 140 may have a gradually increasing degree of hydrophilicity from the 1 st portion 141 to the 2 nd portion 142, or may have a stepwise increasing degree of hydrophilicity from the 1 st portion 141 to the 2 nd portion 142. From the viewpoint of improving the liquid permeability in the thickness direction, the hydrophilicity is preferably gradually increased from the 1 st site 141 to the 2 nd site 142. From the viewpoint of providing a gradient of the degree of hydrophilicity which gradually increases in the degree of hydrophilicity, it is also preferable that the 2 nd layer 140 contains the fiber to which the fiber treatment agent of the present invention described above is attached.

In the 2 nd layer 140, the contact angle of water with respect to the fibers included in the 1 st portion 141 of the 2 nd layer is preferably 50 degrees or more, particularly 60 degrees or more, regardless of whether the degree of hydrophilicity is gradually increased or the degree of hydrophilicity is increased stepwise. Further, it is preferably 80 degrees or less, particularly 75 degrees or less. For example, the contact angle of water with respect to the fibers included in the 1 st portion 141 of the 2 nd layer is preferably 50 degrees or more and 80 degrees or less, and more preferably 60 degrees or more and 75 degrees or less. On the other hand, the contact angle of water with respect to the fibers included in the 2 nd part 142 of the 2 nd layer is preferably 30 degrees or more, particularly 40 degrees or more, under the condition that the contact angle is smaller than the contact angle of water with respect to the fibers included in the 1 st part 141 of the 2 nd layer. Further, it is preferably 75 degrees or less, particularly 70 degrees or less. For example, the contact angle of water with respect to the fibers included in the 2 nd portion 142 of the 2 nd layer is preferably 30 degrees or more and 75 degrees or less, and preferably 40 degrees or more and 70 degrees or less.

In contrast to the 2 nd layer 140 having a gradient in the degree of hydrophilicity, the degree of hydrophilicity of the 1 st layer 130 is the same at any portion of the 1 st layer 130. The hydrophilicity of the layer 1 130 becomes lower than the hydrophilicity of the layer 2 at the 1 st site 141. As described above, the hydrophilicity of the nonwoven fabric 103 shown in fig. 6 increases in the order of the 1 st layer 130, the 2 nd layer 1 st portion 141, and the 2 nd layer 2 nd portion 142. The contact angle of water with respect to the fibers included in the 1 st portion 130 is preferably 75 degrees or more, particularly 80 degrees or more, and preferably 90 degrees or less, particularly 85 degrees or less, provided that the contact angle is larger than the contact angle of water with respect to the fibers included in the 1 st portion 141 of the 2 nd layer. For example, the contact angle of water with respect to the fibers included in the 1 st layer 130 is preferably 75 degrees or more and 90 degrees or less, and preferably 80 degrees or more and 85 degrees or less.

In order to form the 1 st layer 130 having the same degree of hydrophilicity at any position, for example, a conventionally used agent called an oil agent for imparting hydrophilicity to fibers may be used. For example, the above anionic, cationic, amphoteric and nonionic surfactants can be used. The constituent fibers of the 1 st layer 130 are preferably not treated with any of the components (a) to (C) described above. At this time, the liquid film cracking agent is preferably attached to at least the 1 st layer 130, and more preferably attached to the 2 nd layer 140 in addition to the 1 st layer 130.

In the nonwoven fabric 103 shown in fig. 6, from the viewpoint of allowing liquid to further smoothly permeate from the 1 st layer 130 to the 2 nd layer 140, the difference between the contact angle of water with respect to the fibers contained in the 1 st layer 130 and the contact angle of water with respect to the fibers contained in the 1 st portion 141 of the 2 nd layer (1 st layer 130 to 2 nd portion 141) is preferably 1 degree or more, particularly 10 degrees or more, further 15 degrees or more, and preferably 40 degrees or less, particularly 30 degrees or less, further 25 degrees or less. For example, the difference is preferably 1 degree or more and 40 degrees or less, more preferably 10 degrees or more and 30 degrees or less, and further preferably 15 degrees or more and 25 degrees or less.

From the same viewpoint as described above, in the nonwoven fabric 103 shown in fig. 6, the difference between the contact angle of water with respect to the fibers contained in the 1 st layer 130 and the contact angle of water with respect to the fibers contained in the 2 nd part 142 of the 2 nd layer (the 1 st layer 130 to the 2 nd part 142 of the 2 nd layer) is preferably 2 degrees or more, particularly 10 degrees or more, further more preferably 20 degrees or more, further preferably 60 degrees or less, particularly 50 degrees or less, further more preferably 35 degrees or less, provided that the difference is larger than the difference between the contact angles of the 1 st layer 130 to the 1 st part 141 of the 2 nd layer. For example, the difference is preferably 2 degrees or more and 60 degrees or less, more preferably 10 degrees or more and 50 degrees or less, and still more preferably 20 degrees or more and 35 degrees or less.

In order to produce the nonwoven fabrics (through-air nonwoven fabrics) 100, 101, 102 satisfying the above condition I and the nonwoven fabric (through-air nonwoven fabric) 103 satisfying the above condition II, there is a method of using the above-described fiber treatment agent of the present invention and appropriately controlling the blowing conditions of hot air in the heat treatment by the above-described hot air method or the like, that is, the temperature or the air volume of the hot air.

For example, in order to provide the hydrophilicity gradient defined in the above (11) on the 1 st layer, it is preferable that the 1 st layer contains fibers to which the above-mentioned fiber treatment agent of the present invention is attached. Similarly, in order to provide the hydrophilicity gradient defined in the above (22) in the 2 nd layer, it is preferable that the fibers to which the fiber treatment agent of the present invention is attached are contained in the 2 nd layer. In this case, the degree of hydrophilicity of the 1 st layer or the 2 nd layer may be gradually increased from the 1 st portion to the 2 nd portion, or the degree of hydrophilicity may be gradually increased from the 1 st portion to the 2 nd portion. From the viewpoint of improving the liquid permeability in the thickness direction, the degree of hydrophilicity of the 1 st layer or the 2 nd layer is preferably gradually increased from the 1 st portion to the 2 nd portion.

In particular, in the case of producing the nonwoven fabric 102 shown in fig. 5, in order to make the relationship of the degree of hydrophilicity between the 1 st layer 2 nd site 133 and the 2 nd layer 1 st site 143 contrary to the nonwoven fabric 101 shown in fig. 4, it is advantageous to select each fiber treatment agent so that the degree of hydrophilicity becomes lower than that of the fiber treatment agent used for the 2 nd layer 140 when comparing the fiber treatment agent used for the 1 st layer 130 with that of the fiber treatment agent used for the 2 nd layer 140. Even when the above-described heat-extensible fibers are used as the constituent fibers of the 2 nd layer 140, the relationship between the hydrophilicity in the 1 st layer 2 nd site 133 and the hydrophilicity in the 2 nd layer 1 st site 143 can be reversed from the nonwoven fabric 101 shown in fig. 4.

(preferred embodiment of the nonwoven fabric of the invention having an uneven surface)

Preferred embodiments of the nonwoven fabric of the present invention include: a non-woven fabric having a 1 st surface and a 2 nd surface located on the opposite side thereof, wherein at least the 1 st surface has irregularities including a plurality of protrusions protruding toward the 1 st surface and recesses located between the protrusions.

Specific examples of the nonwoven fabric having the uneven shape will be described below.

For example, a nonwoven fabric shown in fig. 7 to which heat-shrinkable fibers are applied (embodiment 1) can be cited. The nonwoven fabric 10 shown in fig. 7 includes 2 layers, i.e., an upper layer 11 on the 1 st surface 1A (skin contact surface when the topsheet is produced) side and a lower layer 12 on the 2 nd surface 1B (non-skin contact surface when the topsheet is produced) side. The 2 layers are bonded by embossing (pressing) from the first surface 1A in the thickness direction (the portion subjected to embossing is referred to as an embossed concave portion (concave bonding portion) 13). The lower layer 12 is a layer exhibiting heat shrinkage of the heat-shrinkable fiber. The upper layer 11 is a layer containing non-heat-shrinkable fibers, which are partially joined by concave joining portions 13. The non-heat-shrinkable fibers are not limited to those that do not shrink at all by heating, and include those that shrink to such an extent that they do not inhibit the heat shrinkage of the heat-shrinkable fibers of the lower layer 12.

The nonwoven fabric 10 can be produced, for example, from the materials and production methods described in paragraphs [0032] to [0048] of Japanese patent laid-open No. 2002-187228. In this production, for example, a laminate of the upper layer 11 and the lower layer 12 is subjected to embossing from the upper layer side 11, and then heat-shrinkable fibers are heat-shrunk by heat treatment. At this time, the embossed portions adjacent to each other are drawn together by the shrinkage of the fibers, and the interval between the embossed portions is narrowed. By this deformation, the fibers of the upper layer 11 rise toward the 1 st surface 1A with the embossed depressions 13 as the origin points, thereby forming the convex portions 14. Alternatively, the lower layer 12 exhibiting thermal shrinkage is laminated on the upper layer in an elongated state, and then the embossing process described above is performed. Thereafter, when the extended state of the lower layer 12 is released, the upper layer 11 rises toward the 1 st surface 1A to form the convex portion 14. The embossing can be performed by a commonly used method such as hot embossing or ultrasonic embossing. In addition, a bonding method using an adhesive may be used for bonding the two layers.

The nonwoven fabric 10 manufactured as described above is bonded by pressing the upper layer 11 against the lower layer side 12 in the embossed concave portions (concave bonding portions) 13. The embossed depressions 13 are formed in a scattered manner in the planar direction of the nonwoven fabric 10, and the portions surrounded by the embossed depressions 13 are the protrusions 14 protruding from the upper layer 11. The convex portion 14 has a three-dimensional shape, for example, a dome shape. The projections 14 formed by the above-described manufacturing method are in a state in which the fibers are thicker than the lower layer 12. The inside of the convex portion 14 may be filled with fibers as shown in fig. 7, or may have a hollow portion formed by separating the upper layer 11 and the lower layer 12. The embossing depressions 13 and the projections 14 may be arranged in any plane, for example, in a lattice. As the lattice arrangement, there can be mentioned: and an arrangement in which a plurality of rows including a plurality of embossed recesses 13 are arranged in a row, and the intervals between the embossed recesses 13 in each row are shifted by half a pitch between adjacent rows. Instead of the lattice shape, the lattice shape may be arranged in any pattern such as a stripe shape, a checkered shape, or a spiral shape. In addition, the planar shape of the embossed depressions 13 may be circular, elliptical, triangular, square, or other polygonal shapes when arranged in a dot-like manner, and may be set as appropriate. The embossed depressions 13 may be arranged not only in a dot shape but also in a line shape.

The nonwoven fabric 10 has an uneven surface on the 1 st surface 1A side, and the uneven surface has convex portions 14 and embossed concave portions 13, and therefore has excellent shape recovery properties when stretched in the planar direction and excellent compression deformability when compressed in the thickness direction. The fibers of the upper layer 11 are raised to form a relatively bulky nonwoven fabric. This allows a user in contact with the nonwoven fabric 10 to feel a soft and comfortable skin feel. Further, the absorbent article in which the nonwoven fabric 10 is incorporated as a topsheet having the 1 st surface 1A as a skin contact surface and the 2 nd surface 1B as a non-skin contact surface has excellent air permeability on the skin contact surface side due to the irregularities having the convex portions 14 and the embossed concave portions 13.

Further, by containing the fiber treatment agent of the present invention, the nonwoven fabric 10 has less liquid remaining, and further improves the liquid permeability of the portion to which the uneven surface and the emboss are applied densely, and has excellent low liquid-returning property based on the gradient of the degree of hydrophilicity.

The mechanism of exhibiting excellent low liquid-returning property in the nonwoven fabric 10 is, more specifically, as described below.

Namely, the method comprises: the flat surface of the 2 nd surface 1B has a higher hydrophilicity gradient than the tops T of the convex portions 14 having a large thickness on the 1 st surface 1A side or the embossed concave portions 13 having a small thickness. Thus, when liquid enters from the 1 st surface 1A side where the uneven surface is formed, the liquid is easily sucked from the convex portions 14 to the embossed concave portions 13, and further from the convex portions 14 and the embossed portions 13 to the 2 nd surface 1B side, so that the liquid remaining in the nonwoven fabric 10 is reduced, and the liquid return in the reverse direction is suppressed.

The 1 st surface 1A as the uneven surface of the nonwoven fabric 1 is: the side facing the embossing roll during embossing and facing the opposite side of the web surface (air-permeable support) when hot air is applied by the hot air method is the side directly onto which hot air is applied. By this heat treatment, a gradient of hydrophilicity is formed from the 1 st surface 1A side to the 2 nd surface 1B side.

In the convex portion 14, from the viewpoint of allowing the liquid to further smoothly permeate from the top portion to the back surface (the 2 nd surface 1B), a difference between a contact angle of water with respect to the fibers included in the top portion and a contact angle of water with respect to the fibers included in the back surface side is preferably 3 degrees or more, particularly 5 degrees or more, and preferably 25 degrees or less, particularly 20 degrees or less. For example, the difference is preferably 3 degrees or more and 25 degrees or less, and more preferably 5 degrees or more and 20 degrees or less. In order to produce a nonwoven fabric having a difference in contact angle between the top portion T and the constituent fibers on the back surface within the above range, the fiber treatment agent may be used, and the conditions for blowing hot air in the hot air heat treatment, that is, the temperature or the volume of hot air may be appropriately controlled.

The nonwoven fabric 10 is not limited to the 2-layer structure of the upper layer 11 and the lower layer 12, and may further have another layer. For example, a single layer or a plurality of layers may be disposed between the upper layer 11 and the lower layer 12, or a single layer or a plurality of layers may be disposed on the 1 st surface 1A side and the 2 nd surface 1B side of the nonwoven fabric 10. The single layer or the plurality of layers may be a layer having a heat shrinkable fiber or a layer having a non-heat shrinkable fiber.

As another specific example of the nonwoven fabric of the present invention having the uneven shape,

nonwoven fabrics

20, 30, 40, 50, 60, and 70 (embodiments 2 to 7) are shown below.

First, the nonwoven fabric 20 of embodiment 2 has a two-layer structure having a hollow portion 21 as shown in fig. 8. Both layers comprise thermoplastic fibers. The nonwoven fabric 20 has a joining part 22 formed by partially heat-fusing the 1 st nonwoven fabric 20A and the 2 nd nonwoven fabric 20B. In the non-joined portion 24 surrounded by the joined portion 22, the 1 st nonwoven fabric 20A has a plurality of convex portions 23 which protrude in a direction away from the 2 nd nonwoven fabric 20B and have hollow portions 21 therein. The joining portion 22 is a concave portion located between the adjacent convex portions 23, and constitutes the unevenness of the 1 st surface 1A together with the convex portion 23. The nonwoven fabric 20 can be formed by a commonly used method. For example, after the 1 st nonwoven fabric 20A is shaped into an uneven form by meshing of 2 uneven rolls, the 2 nd nonwoven fabric is bonded to obtain the nonwoven fabric 20.

The nonwoven fabric 20 has excellent liquid permeability from the 1 st surface 1A side to the 2 nd surface 2B side when used as a topsheet facing the skin contact surface side of the 1 st surface 1A laminated on an absorbent body, for example. Specifically, the liquid passes through the hollow portion 21. Further, the body pressure of the wearer is applied to the convex portions 23, and the liquid present in the convex portions 23 directly moves to the 2 nd nonwoven fabric 3. This reduces the amount of liquid remaining on the 1 st surface 1A. Further, the heat treatment performed from the 1 st surface 1A provides a gradient of hydrophilicity that increases from the 1 st surface 1A side to the 2 nd surface 1B side, thereby providing excellent low liquid return performance. This effect can be further continuously exhibited by the effect of the liquid film breaking agent possessed by the fiber treatment agent of the present invention described above. That is, even when the liquid is used for a long time or a large amount of liquid is discharged, since the liquid film is broken to secure a liquid permeation path, the liquid permeability as described above is sufficiently exhibited, and the low liquid returning property is maintained even under the body pressure. This widens the design range for the fiber diameter and the fiber density.

As shown in fig. 9(a) and (B), the nonwoven fabric 30 according to embodiment 3 includes a 1 st fiber layer 301 including thermoplastic fibers and having irregularities on both surfaces. Fig. 9(a) shows a nonwoven fabric 30A having a 1-layer structure composed of only the 1 st fiber layer 301. Fig. 9(B) shows a nonwoven fabric 30B having a 2-layer structure including a 1 st fiber layer 301 and a 2 nd fiber layer 302 joined along the 2 nd surface 1B side of the 1 st fiber layer 301. Hereinafter, each nonwoven fabric will be specifically described.

In the nonwoven fabric 30A (the 1 st fiber layer 301) shown in fig. 9 a, the 1 st protrusions 31 protruding toward the 1 st surface 1A and the 2 nd protrusions 32 protruding toward the 2 nd surface 1B are alternately and continuously arranged in different intersecting directions in a plan view of the nonwoven fabric 30A. The 1 st projection 31 and the 2 nd projection 32 have internal spaces open to the opposite surfaces thereof, and these portions form recesses 33 and 34 in the surfaces. Thus, the 1 st surface 1A has a concave-convex shape of the 1 st protrusion 31 and the concave portion 34. The 2 nd surface 1B is a concave-convex shape of the 2 nd projecting portion 32 and the concave portion 33. The nonwoven fabric 30A has wall portions 35 connecting the 1 st and 2

nd protrusions

31 and 32. The wall 35 forms a wall surface of the internal space of each of the 1 st projection 31 and the 2 nd projection 32, and has an annular structure in a planar direction. The fibers constituting the wall 35 have fiber orientation in the direction connecting the 1 st projection 31 and the 2 nd projection 32 at any position of the annular structure. This produces toughness in the wall. As a result, the nonwoven fabric 30A has appropriate cushioning properties, has excellent recovery properties even when pressure is applied, and can prevent collapse of each internal space. Further, the double-sided protrusions provide high dispersibility to body pressure and also suppress the contact area, and therefore the skin feels soft and the liquid-return prevention property is excellent. The nonwoven fabric 30A can be used as a topsheet of an absorbent article with either surface thereof being a skin contact surface side, and can impart appropriate cushioning properties, a soft skin feel, and excellent low liquid return performance to the absorbent article.

The nonwoven fabric 30B shown in fig. 9(B) is formed by bonding the 2 nd fiber layer 302 along the irregularities on the 2 nd surface 1B side of the 1 st fiber layer 301. The nonwoven fabric 30B is typically used with the 1 st surface 1A being a skin contact surface. On the 1 st surface 1A side of the nonwoven fabric 30B, the 1 st protrusions 31 and the recesses 34 of the 1 st fiber layer 301 have a spread uneven shape, and wall portions 35 having an annular structure between the 1 st protrusions 31 and the recesses 32 are arranged. Therefore, the nonwoven fabric 30B also has the fiber orientation of the 1 st fiber layer 301 described above, and thus has excellent recovery properties of unevenness due to toughness of the wall portion.

In addition, the nonwoven fabric 30B is formed into a fiber web, nonwoven fabric, and two layers are joined by hot air treatment in a hot air process, and therefore, is bulky as a whole and has a low basis weight. In particular, since the two

fiber layers

301 and 302 are bonded by thermal fusion of the fibers with hot air, a gap is formed between the fibers at the bonded portion between the fiber layers, and the liquid passing speed is high even in the concave portion 32 serving as the bonded portion. Further, the 2 nd fiber layer 302 has a portion 36, on the 2 nd surface 1B side of the top portion of the 1 st protrusion 31 of the 1 st fiber layer 301, in which the fiber density is lower than the fiber density of the other portions of the 1 st fiber layer 301 and the 2 nd fiber layer 302. By the presence of the low fiber density portion 36, the 1 st protruding portion 31 of the 1 st fiber layer 301 is easily dented even at a low load, and therefore, the cushioning property of the nonwoven fabric 30B can be improved. When the nonwoven fabric 30B is used as a topsheet of an absorbent article, the 1 st surface 1A side (i.e., the 1 st fiber layer 301 side) is preferably set to be the skin contact surface side.

In addition, the nonwoven fabric 30(30A and 30B) also has a higher degree of hydrophilicity gradient from the 1 st surface 1A side to the 2 nd surface 1B side by performing the heat treatment from the 1 st surface 1A, and thus has further excellent low liquid-returning property. This effect can be further continuously exhibited by the effect of the liquid film breaking agent possessed by the fiber treatment agent of the present invention described above. That is, even when the liquid container is used for a long time or a large amount of liquid is discharged, the liquid film breaks to secure a liquid permeation path, and thus the liquid permeability as described above is sufficiently exhibited, and the low liquid returning property is maintained even under a body pressure. This widens the design range for the fiber diameter and the fiber density.

In the production of the nonwoven fabric 30(30A and 30B), for example, hot air processing may be employed in which a web is subjected to multi-stage hot air treatment while controlling the temperature and the wind speed of the hot air. For example, the nonwoven fabric 30A (the 1 st fiber layer 301) can be produced by the production method described in paragraphs [0031] and [0032] of japanese patent application laid-open No. 2012 and 136790. In addition, as the support for shaping the unevenness of the web, a support having solid protrusions and openings is preferably used. For example, the support shown in FIGS. 1 and 2 of Japanese patent application laid-open No. 2012 and 149370 or the support shown in FIGS. 1 and 2 of Japanese patent application laid-open No. 2012 and 149371 can be used. The nonwoven fabric 30B (a laminated nonwoven fabric of the 1 st fiber layer 301 and the 2 nd fiber layer 302) can be produced by laminating a fiber web to be the 2 nd fiber layer 302 in the hot air step of the 1 st fiber layer 301. For example, the production method described in paragraphs [0042] to [0064] of Japanese patent application laid-open No. 2013-124428 can be used.

As shown in fig. 10, the nonwoven fabric 40 according to embodiment 4 includes 1 layer containing thermoplastic fibers, and has a shape in which a plurality of semi-cylindrical convex portions 41 and concave portions 42 arranged along the side edges of the convex portions 41 are alternately arranged on the 1 st surface 1A side. A recess bottom 43 containing fibers of nonwoven fabric is disposed below the recess 42. The fiber density of the bottom 43 of the recess is lower than that of the protrusion 41. In the nonwoven fabric 30, another fiber layer 45 may be partially laminated on the convex portions 41 (see fig. 11). When the nonwoven fabric 40 is incorporated into an absorbent article as a topsheet having the 1 st surface 1A side as the skin contact surface side, the liquid received by the convex portions 41 is likely to move toward the concave portions 42, and the liquid is likely to move toward the 2 nd surface 1B side in the concave portions 43. This reduces the amount of liquid remaining, and suppresses the sticky feeling of the skin. Further, the heat treatment is performed from the 1 st surface 1A, so that the hydrophilicity is increased from the 1 st surface 1A side to the 2 nd surface 1B side, thereby providing excellent low liquid-returning performance.

The nonwoven fabric 40 also has excellent low-rewet properties while always ensuring a liquid permeation path by the action of the liquid film-splitting agent possessed by the fiber treatment agent of the present invention. This widens the design range for the fiber diameter and the fiber density.

Such a nonwoven fabric 40 can be formed by blowing a fluid such as hot air to the portion of the fiber web to be the concave portion 42 to move the fibers. This makes it possible to lower the fiber density of the recess bottom 43 than that of the periphery thereof.

As shown in fig. 12, the nonwoven fabric 50 according to embodiment 5 has a concave-convex structure in which stripe-shaped convex portions 51 and concave portions 52 extending in one direction (Y direction) are alternately arranged. In the thickness direction of the nonwoven fabric sheet 50, the uneven structure may be divided into 3 equal parts of a top region 50A, a bottom region 50B, and a side region 50C therebetween.

The nonwoven fabric 50 has a plurality of heat-fused portions 55 constituting intersections of the fibers 54. Focusing on 1 constituent fiber 54, the constituent fibers 54 have large diameter portions 57 sandwiched between 2 small diameter portions 56 having a small fiber diameter between adjacent fusion portions 55, as shown in fig. 13. This improves the flexibility of the nonwoven fabric 50 and improves the texture. In addition, the contact area with the skin is reduced in terms of fiber units, and a more satisfactory dry feeling is obtained. From the viewpoint of flexibility, the point of change 58 from the small diameter portion 56 to the large diameter portion 57 is preferably in a range close to 1/3 of the fused portion 55 (the range of T1 and T3 in fig. 13) of the interval T between the adjacent fused

portions

55 and 55. Further, a plurality of combinations of the small diameter portions 56 and the large diameter portions 57 held therebetween may be present in the interval T. The small diameter portion 56 and the large diameter portion 57 in the constituent fiber are formed by drawing the fiber at the time of the sipe drawing process for forming the convex portion 51 and the concave portion 52. The fiber used in this case is preferably a fiber having a high degree of stretchability. Examples thereof include: a heat-stretchable fiber in which the crystalline state of the resin obtained by the treatment process described in paragraph [0033] of Japanese patent application laid-open No. 2010-168715 is changed by heating to generate a long stretch.

Further, from the viewpoint of liquid permeability, the nonwoven fabric 50 preferably has a smaller degree of hydrophilicity in the small diameter portion than in the large diameter portion. The difference in the degree of hydrophilicity can be formed by incorporating a fiber treatment agent attached to the fiber with a stretching component (hydrophobic component). Particularly preferably contains an extensible component and a hydrophilic component. Specifically, when the fiber is drawn by the above-described sipe drawing process, the drawing component is diffused in the drawn small diameter portion 35 to generate a difference in hydrophilicity with the large diameter portion. In the large diameter portion, the hydrophilic component which is not easily diffused is retained and the hydrophilicity becomes higher than that in the small diameter portion. Examples of the tensile component include silicone resins having a low glass transition point and a flexible molecular chain, and polyorganosiloxane having a Si — O — Si chain as a main chain is preferably used as the silicone resin.

In view of the liquid permeability, the nonwoven fabric 50 preferably has a fiber density in the side wall regions 30C that is lower than the fiber density in the top regions 30A and the bottom regions 30B.

The nonwoven fabric 50 also has excellent low liquid-returning properties because it has a high degree of hydrophilicity from the 1 st surface 1A side to the 2 nd surface 1B side by performing the heat treatment from the 1 st surface 1A. Further, the fiber treatment agent of the present invention has excellent low liquid return performance by the action of the liquid film breaking agent, and the liquid permeation path is always ensured. This widens the design range for the fiber diameter and the fiber density.

The nonwoven fabric 50 may be used alone, or may be joined to a flat fiber layer to form a laminated nonwoven fabric, or may be laminated to a fiber layer having irregularities to form a laminated nonwoven fabric integrated along the irregularities. For example, the nonwoven fabric may be laminated on the 2 nd nonwoven fabric among the nonwoven fabrics 20 of the 2 nd embodiment (fig. 8), or may be laminated on the nonwoven fabric 30A of the 3 rd embodiment (fig. 9(a)) or the nonwoven fabric 40 of the 4 th embodiment (fig. 10 or 11).

The nonwoven fabric 60 according to embodiment 6 has an uneven shape including thermally extensible fibers. As shown in fig. 14(a) and (B), the surface 1A has a concave-convex shape having a thin portion 68 and a thick portion 69 other than the thin portion. The 2 nd surface 1B side is flat or the degree of unevenness is extremely small as compared with the 1 st surface 1A side. The uneven shape on the 1 st surface 1A side specifically includes a plurality of convex portions 61 (thick portions 69) and linear concave portions 62 (thin portions 68) surrounding the convex portions. The concave portion 62 has a pressure-bonded portion to which the constituent fibers of the nonwoven fabric 60 are pressure-bonded or bonded, and the heat-expandable fiber is in a non-expanded state. The convex portion 61 is a portion where the thermally extensible fiber is thermally extended and raised toward the 1 st surface 1A. Therefore, the convex portions 61 are bulkier portions because the fiber density is lower than that of the concave portions 62. The linear recesses 62 are arranged in a grid pattern, and the projections 61 are arranged in a scattered manner in each region divided by the grid pattern. This allows the nonwoven fabric 60 to control the contact area with the skin of the wearer, thereby effectively preventing stuffiness and rash. The convex portions 61 that contact the skin are bulky due to thermal elongation of the thermally extensible fibers, and have a soft skin feel. The nonwoven fabric 60 may have a single-layer structure or a multilayer structure having 2 or more layers. For example, in the case of a 2-layer structure, the layer on the 2 nd surface 1B side preferably contains no thermally extensible fibers, or contains less thermally extensible fibers than the layer on the 1 st surface 1A side having the uneven shape. Further, the two layers are preferably joined by the pressure-bonded portion of the recess 62.

The nonwoven fabric 60 also has a higher degree of hydrophilicity from the 1 st surface 1A side to the 2 nd surface 1B side by performing heat treatment such as embossing treatment or hot air treatment with hot air described below on the 1 st surface 1A. This provides excellent low liquid-returning properties. Further, the fiber treatment agent of the present invention has excellent low liquid return performance by the action of the liquid film breaking agent, while always ensuring a liquid permeation path. This widens the design range for the fiber diameter and the fiber density.

As the gradient of the degree of hydrophilicity, specifically, as shown in fig. 14(B), it is preferable that the contact angle of water with respect to the fibers of the flat surface (back surface) P2 on the 2 nd surface 1B side of the convex portion 61 is smaller than the contact angle of water with respect to the fibers of the top portion P1 of the convex portion 61. Thus, when the side of the 1 st surface 1A is set to the skin contact surface side of the absorbent article, the convex portions 61 having a thickness greater than the concave portions 62 allow liquid to more smoothly permeate through the back surface P2 in the thickness direction from the top portion P1 that directly receives excreted liquid, and the low liquid retention property is further improved. From this viewpoint, the difference between the contact angle of water with respect to the fibers of the top P1 and the contact angle of water with respect to the fibers of the back P2 (top P1 — back P2) is preferably 3 degrees or more, more preferably 5 degrees or more, and preferably 25 degrees or less, more preferably 20 degrees or less. For example, the difference is preferably 3 degrees or more and 25 degrees or less, and more preferably 5 degrees or more and 20 degrees or less.

Such a nonwoven fabric 60 can be produced, for example, by the process shown in fig. 15. First, a web 612 is formed by a carding machine 611. The web 612 is introduced into an embossing apparatus 613 having a pair of rollers 614 and 615 and is subjected to hot embossing, thereby forming linear depressions 62. At this time, the heat-extensible fibers are fixed without being heat-extended by being pressure-bonded or fused in the recesses 62. Subsequently, the embossed web 616 is heat-treated by a hot air treatment device 617 using a hot air method, thereby obtaining a nonwoven fabric 60. At this time, the hot-extensible fibers present in the portions other than the recessed portions 62 are extended by hot air processing to form the raised portions 61. In order to produce a nonwoven fabric having a difference in contact angle within the above range, the fiber treatment agent of the present invention may be used, and the blowing conditions of hot air (temperature or air volume of hot air) in the hot air heat treatment may be appropriately controlled. The constituent fibers of the nonwoven fabric 60 may be a blend of the above-described heat-extensible fibers and the non-heat-extensible heat-fusible fibers. Examples of the constituent fibers include fibers described in paragraphs [0013] and [0037] to [0040] of Japanese patent application laid-open No. 2005-350836, and fibers described in paragraphs [0012] and [0024] to [0046] of Japanese patent application laid-open No. 2011-1277258.

As shown in fig. 16, the nonwoven fabric 70 according to embodiment 7 includes: a laminated nonwoven fabric comprising an upper layer 71 and a lower layer 72 of thermoplastic fibers. The convex portions 73 and the concave portions 74 are alternately arranged on the upper layer 71, and the concave portions 74 are opened. The fiber density of the concave portions 74 is lower than that of the convex portions 73. The region where the convex portions 73 and the concave portions 74 are alternately and repeatedly arranged may be present in a part of the upper layer 71 or may be present in the entirety. When a region in which the convex portions 73 and the concave portions 74 are alternately and repeatedly arranged exists in a part of the upper layer, the region is preferably present in a portion which becomes a liquid receiving region (excretion portion corresponding region) when the nonwoven fabric 70 is used as a topsheet of an absorbent article. On the other hand, the lower layer 72 has a substantially uniform fiber density. The lower layer 72 is laminated at least in correspondence with the region of the upper layer 71 in which the convex portions 73 and the concave portions 74 are alternately and repeatedly arranged. Thus, the nonwoven fabric 70 has a bulky cushioning property due to the high fiber density of the convex portions 73, and is less likely to cause liquid back when used as a topsheet of an absorbent article. Further, since the nonwoven fabric 70 is in an open state due to the low fiber density of the concave portions 74, the liquid permeability, particularly, the permeability to a highly viscous liquid is excellent.

The nonwoven fabric 70 also has a high degree of hydrophilicity from the 1 st surface 1A side to the 2 nd surface 1B side by performing the heat treatment from the 1 st surface 1A, and thus has excellent low liquid-returning property. Further, the fiber treatment agent of the present invention has excellent low liquid return performance by the action of the liquid film breaking agent, while always ensuring a liquid permeation path. This widens the design range of the fiber diameter and the fiber density.

Such a nonwoven fabric 70 can be produced by the method described in, for example, Japanese patent laid-open No. 4-24263 on page 6, line 12 of the lower left column to page 8, line 19 of the upper right column.

The nonwoven fabric of the present invention can be applied to various fields by effectively utilizing its soft touch and reduced liquid residue. For example, the sheet is suitably used as a topsheet, a second sheet (a sheet disposed between the topsheet and the absorbent body), a backsheet, a leakage-preventing sheet, a wipe sheet for personal use, a skin care sheet, a wipe for articles, and the like in an absorbent article used for absorbing a liquid discharged from the body such as a sanitary napkin, a panty liner, a disposable diaper, an incontinence pad, and the like. When the nonwoven fabric of the present invention is used as a topsheet or a second sheet of an absorbent article, the 1 st layer side of the nonwoven fabric is preferably used as the skin-facing surface side. The fiber treatment agent of the present invention is not limited to nonwoven fabrics as long as it has the function of splitting a liquid film, and can be applied to various fiber materials such as woven fabrics.

The basis weight of the web used for producing the nonwoven fabric of the present invention is appropriately selected depending on the specific use of the target nonwoven fabric. The basis weight of the finally obtained nonwoven fabric is preferably 10g/m²Above and 80g/m²Below, in particular 15g/m²Above and 60g/m²The following.

An absorbent article used for absorbing liquid discharged from the body typically includes a topsheet, a backsheet, and a liquid-retentive absorbent member interposed between the two sheets. In the case of using the nonwoven fabric of the present invention as a topsheet, the absorbent material and the backsheet can be made of materials generally used in the technical fields, and are not particularly limited. For example, as the absorbent, a fiber aggregate containing a fiber material such as pulp fiber covered with a covering sheet such as toilet paper or nonwoven fabric, or a fiber aggregate having an absorbent polymer retained therein can be used. As the back sheet, a liquid impermeable or water repellent sheet such as a film of a thermoplastic resin or a laminate of the film and a nonwoven fabric can be used. The back sheet may also have water vapor permeability. The absorbent article may further include various members corresponding to specific uses of the absorbent article. Such components are well known to the practitioner. For example, when the absorbent article is used for a disposable diaper or a sanitary napkin, one or two or more pairs of three-dimensional guards may be arranged on both the left and right side portions of the topsheet.

The present invention further discloses the following nonwoven fabric, absorbent article and fiber treatment agent.

＜1＞

A nonwoven fabric having a fiber-treating agent adhered thereto, wherein the fiber-treating agent comprises a liquid film-cracking agent and 1 or more selected from the following components (A), (B) and (C).

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 27]

(wherein Z represents a group having a valence of 3 and selected from the group consisting of a linear or branched alkyl chain having 1 to 12 carbon atoms which may contain an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond R⁷And R⁸Each independently represents a group which may contain an ester groupAn amide group, a polyoxyalkylene group, an ether group or a linear or branched alkyl group having 2 to 16 carbon atoms in the double bond. X represents-SO₃M、-OSO₃M or-COOM, M represents H, Na, K, Mg, Ca or ammonium).

＜2＞

The nonwoven fabric according to the above < 1 >, wherein the water solubility of the liquid film opener is 0g or more and 0.025g or less.

＜3＞

The nonwoven fabric according to the above < 1 > or < 2 >, wherein the spreading factor of the liquid film-splitting agent with respect to a liquid having a surface tension of 50mN/m is 15 or more.

＜4＞

A nonwoven fabric comprising the following compound and 1 or more selected from the following component (A), component (B) and component (C).

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 28]

＜5＞

The nonwoven fabric according to any one of the above < 1 > to < 4 >, wherein the spreading factor of the compound or the liquid film opener is more preferably 20mN/m or more, still more preferably 25mN/m or more, and particularly preferably 30mN/m or more.

＜6＞

The nonwoven fabric according to any one of the above < 1 > to < 5 >, wherein the interfacial tension of the compound or the liquid film opener with respect to a liquid having a surface tension of 50mN/m is preferably 20mN/m or less, more preferably 17mN/m or less, further preferably 13mN/m or less, further more preferably 10mN/m or less, particularly preferably 9mN/m or less, particularly preferably 1mN/m or less, and more than 0 mN/m.

＜7＞

The nonwoven fabric according to any one of the above items < 1 > to < 6 >, wherein the compound or the liquid film cleavage agent contains a compound having at least 1 structure selected from the following structures X, X-Y and Y-X-Y.

Structure X represents: < C (A) - (C represents a carbon atom, <, > and-represent a bond, the same shall apply hereinafter), -C (A)₂-、-C(A)(B)-、＞C(A)-C(R¹)＜、＞C(R¹)-、-C(R¹)(R²)-、-C(R¹)₂-, > C < and, -Si (R)¹)₂O-、-Si(R¹)(R²) A siloxane chain having a repeating arbitrary basic structure or a combination of 2 or more structures in O-, or a mixed chain thereof,

structure X is terminated by a hydrogen atom, or is selected from-C (A)₃、-C(A)₂B、-C(A)(B)₂、-C(A)₂-C(R¹)₃、-C(R¹)₂A、-C(R¹)₃or-OSi (R)¹)₃、-OSi(R¹)₂(R²)、-Si(R¹)₃、-Si(R¹)₂(R²) At least 1 group selected from the group consisting of,

the R is¹Or R²Each independently represents a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, or a halogen atom,

A. b independently represent a substituent containing an oxygen atom or a nitrogen atom,

a plurality of R are respectively present in the structure X ¹、R²A, B, which may be the same or different from each other,

y represents a hydrophilic group having hydrophilicity and containing an atom selected from the group consisting of a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a phosphorus atom and a sulfur atom, and Y is the same or different when plural.

＜8＞

The nonwoven fabric according to any one of the above-mentioned items < 1 > to < 7 >, wherein the compound or the liquid film cleavage agent comprises a compound containing a siloxane chain in which structures represented by the following formulae (1) to (11) are optionally combined.

[ chemical formula 29]

In formulae (1) to (11), M¹、L¹、R²¹And R²²Represents the following 1-valent or polyvalent group, R²³And R²⁴Represents a 1-valent or polyvalent group having a valence of 2 or more, or a single bond,

M¹a group having a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group in which these groups are combined, an erythritol group, a xylitol group, a sorbitol group, a glyceryl group, or an ethylene glycol group, a hydroxyl group, a carboxylic acid group, a mercapto group, an alkoxy group, an amino group, an amide group, an imino group, a phenolic group, a sulfonic acid group, a quaternary ammonium group, a sulfobetaine group, a hydroxysulfobetaine group, a phosphobetaine group, an imidazolium betaine group, a carbonylbetaine group, an epoxy group, a carbinol group, a (meth) acryloyl group, or a functional group in which these groups are combined, and M is a monomer represented by ¹In the case of a polyvalent radical, M¹Represents a group obtained by further removing 1 or more hydrogen atoms from each of the above-mentioned groups or functional groups,

L¹a bonding group of an ether group, an amino group, an amide group, an ester group, a carbonyl group or a carbonate group as L¹Ammonia that can be usedRadical of > NR^CIs represented by R^CIs a hydrogen atom or a monovalent group,

R²¹、R²²、R²³and R²⁴Each independently represents an alkyl group, an alkoxy group, an aryl group, a fluoroalkyl group, or an aralkyl group, or a hydrocarbon group containing these groups in combination, or a halogen atom.

＜9＞

The nonwoven fabric according to any of the above < 1 > to < 8 >, wherein the compound or the liquid film cleavage agent contains a compound having a siloxane chain in its main chain.

＜10＞

The nonwoven fabric according to any of the above-mentioned < 1 > to < 8 >, wherein the compound or the liquid film cleavage agent preferably contains a modified silicone having a structure having at least one oxygen atom in a modified group.

＜11＞

The nonwoven fabric according to any of the above-mentioned < 1 > to < 10 >, wherein the compound or the liquid film cleavage agent contains a polyoxyalkylene-modified silicone.

＜12＞

The nonwoven fabric according to the above < 11 >, wherein the polyoxyalkylene-modified silicone is represented by any one of the following formulas [ I ] to [ IV ].

[ chemical formula 30]

[ chemical formula 31]

[ chemical formula 32]

[ chemical formula 33]

In the formula, R³¹Represents an alkyl group, R³²Represents a single bond or an alkylene group, a plurality of R³¹A plurality of R³²Respectively, are the same as or different from each other,

M¹¹represents a group having a polyoxyalkylene group, and examples of the polyoxyalkylene group include: polyoxyethylene, polyoxypropylene, and polyoxybutylene groups obtained by copolymerizing these constituent monomers,

m and n are each independently an integer of 1 or more.

＜13＞

The nonwoven fabric according to < 11 > or < 12 > above, wherein the polyoxyalkylene-modified silicone has at least 1 of polyoxyethylene, polyoxypropylene, and polyoxybutylene groups, and groups obtained by copolymerizing these constituent monomers, as the polyoxyalkylene group.

＜14＞

The nonwoven fabric according to any one of the above < 11 > to < 13 >, wherein the number of addition mols of the polyoxyalkylene group of the polyoxyalkylene modified silicone is preferably 1 or more, more preferably 3 or more, and even more preferably 5 or more, and the number of addition mols is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less.

＜15＞

The nonwoven fabric according to the above < 1 > or < 2 >, wherein the liquid film cleavage agent has a spreading factor of more than 0mN/m with respect to a liquid having a surface tension of 50mN/m and an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50 mN/m.

＜16＞

A nonwoven fabric comprising the following compound and 1 or more selected from the following component (A), component (B) and component (C),

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 34]

(wherein Z represents a group having a valence of 3 and selected from the group consisting of a linear or branched alkyl chain having 1 to 12 carbon atoms and optionally containing an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond,

R⁷and R⁸Each independently represents a linear or branched alkyl group having 2 to 16 carbon atoms which may contain an ester group, an amide group, a polyoxyalkylene group, an ether group or a double bond,

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium).

＜17＞

The nonwoven fabric according to < 15 > or < 16 > above, wherein the interfacial tension of the compound or the liquid film opener with respect to a liquid having a surface tension of 50mN/m is preferably 17mN/m or less, more preferably 13mN/m or less, further preferably 10mN/m or less, particularly preferably 9mN/m or less, particularly preferably 1mN/m or less, and more than 0 mN/m.

＜18＞

The nonwoven fabric according to any one of the above < 15 > to < 17 >, wherein the spreading factor of the compound or the liquid film opener with respect to a liquid having a surface tension of 50mN/m is preferably 9mN/m or more, more preferably 10mN/m or more, still more preferably 15mN/m or more, and is 50mN/m or less.

＜19＞

The nonwoven fabric according to any one of the above < 15 > to < 18 >, wherein the compound or the liquid film cleavage agent comprises a compound having at least 1 structure selected from the following structures Z, Z-Y and Y-Z-Y,

structure Z represents: > C (A) - (C: carbon atom), -C (A)₂-、-C(A)(B)-、＞C(A)-C(R³)＜、＞C(R³)-、-C(R³)(R⁴)-、-C(R³)₂A hydrocarbon chain having a repeating structure of any basic structure of-C or > C < or a combination of 2 or more structures,

having a hydrogen atom at the terminus of structure Z, or selected from-C (A)₃、-C(A)₂B、-C(A)(B)₂、-C(A)₂-C(R³)₃、-C(R³)₂A、-C(R³)₃At least 1 group selected from the group consisting of,

the R is³Or R⁴Each independently represents a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, a fluoroalkyl group, an aralkyl group, a hydrocarbon group in which these groups are combined, or a fluorine atom,

y represents a hydrophilic group having hydrophilicity and containing an atom selected from the group consisting of a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a phosphorus atom and a sulfur atom, and Y is the same or different from each other when plural.

＜20＞

The nonwoven fabric according to the above < 19 >, wherein Y is a hydrophilic group comprising: any of a hydroxyl group, a carboxylic acid group, an amino group, an amide group, an imino group, and a phenol group; or a polyoxyalkylene group; or any of erythritol group, xylitol group, sorbitol group, glycerin group, and ethylene glycol group; or any of a sulfonic acid group, a sulfuric acid group, a phosphoric acid group, a sulfobetaine group, a carbonylbetaine group, a phosphobetaine group, a quaternary ammonium group, an imidazolium betaine group, an epoxy group, a carbinol group, and a methacryl group; or a combination of these groups.

＜21＞

The nonwoven fabric according to any of the above < 15 > to < 20 >, wherein the compound or the liquid film cleavage agent contains a polyoxyalkylene alkyl ether or a hydrocarbon compound having 5 or more carbon atoms.

＜22＞

The nonwoven fabric according to any one of the above-mentioned < 15 > to < 21 >, wherein the compound or the liquid film cleavage agent is any one of polyoxyalkylene alkyl (POA) ether represented by the following formula [ V ], or any one of polyoxyalkylene glycol having a molecular weight of 1000 or more represented by the following formula [ VI ], steareth, behenyl ether, PPG myristyl ether, PPG stearyl ether, and PPG behenyl ether.

[ chemical formula 35]

[ chemical formula 36]

In the formula, L²¹Represents an ether group, an amino group, an amide group, an ester group, a carbonyl group, a carbonate group, a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, or a polyoxyalkylene group in which these groups are combined,

R⁵¹represents a substituent comprising: a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, a nonyl group, a decyl group, a methoxy group, an ethoxy group, a phenyl group, a fluoroalkyl group, an aralkyl group, a hydrocarbon group having these groups in combination, or a fluorine atom,

in addition, a, b, m and n are each independently an integer of 1 or more,

here, C_mH_nRepresents alkyl (n ═ 2m +1), C_aH_bRepresents an alkylene group (a ═ 2b),

the number of carbon atoms and the number of hydrogen atoms are independently defined in each of the formulae (V) and (VI), do not necessarily represent the same integer, and may be different,

furthermore, - (C)_aH_bO)_m"m" of (E) is an integer of 1 or more, and the values of the repeating units are determined independently in each of the formulae (V) and (VI), and do not necessarily represent the same integer, and may be different.

＜23＞

The nonwoven fabric according to any of the above < 15 > to < 22 >, wherein the compound or the liquid film cleavage agent contains a compound having a polyoxyalkylene group, and the molar number of the polyoxyalkylene group is 1 or more and 70 or less, more preferably 5 or more, further preferably 7 or more, and preferably 70 or less, more preferably 60 or less, further preferably 50 or less.

＜24＞

The nonwoven fabric according to any one of the above <15> to < 23 >, wherein the compound or the liquid film cleavage agent contains a hydrocarbon compound having 5 or more, preferably 100 or less, more preferably 50 or less carbon atoms.

＜25＞

The nonwoven fabric according to the above < 24 >, wherein the hydrocarbon compound is a hydrocarbon compound excluding polyorganosiloxane.

＜26＞

The nonwoven fabric according to the above < 24 > or < 25 >, wherein the hydrocarbon compound is represented by any one of the following formulas [ VII ] to [ XV ].

[ chemical formula 37]

C_mH_n-COOH [VII]

[ chemical formula 38]

[ chemical formula 39]

[ chemical formula 40]

[ chemical formula 41]

[ chemical formula 42]

[ chemical formula 43]

[ chemical formula 44]

C_mH_n-OH [XIII]

[ chemical formula 45]

C_mH_n-COO-C_mH_n [XIV]

[ chemical formula 46]

C_mH_n [XV]

In the formulas [ VII ] to [ XV ], m ', n ', and n ' are each independently an integer of 1 or more, and a plurality of m and a plurality of n are each the same or different from each other,

in addition, formula [ X]In, R⁵²Represents a linear or branched, saturated or unsaturated hydrocarbon group having 2 to 22 carbon atoms.

<27>

The nonwoven fabric according to any one of the above <15> to <26>, wherein the spreading factor of the compound or the liquid film opener with respect to a liquid having a surface tension of 50mN/m is 9mN/m or more, the water solubility is 0g or more and 0.025g or less, the interfacial tension with respect to a liquid having a surface tension of 50mN/m is 9mN/m or less, and the surface tension is 32mN/m or less.

<28>

As described above<1>To<27>The nonwoven fabric according to any of the above, wherein the water solubility of the compound or the liquid film-splitting agent is preferably 0.0025g or less, more preferably 0.0017g or less, further preferably less than 0.0001g, and preferably 1.0X 10^-9g is above.

＜29＞

The nonwoven fabric according to any one of the above < 1 > to < 28 >, wherein the nonwoven fabric further comprises a phosphate ester type anionic surfactant.

＜30＞

The nonwoven fabric according to < 29 > above, wherein the content ratio of the compound or the liquid film-splitting agent to the phosphate ester type anionic surfactant (liquid film-splitting agent/phosphate ester type anionic surfactant) is 1.8 or less by mass ratio.

＜31＞

The nonwoven fabric according to < 30 > above, wherein the content ratio of the compound or the liquid film cracking agent to the phosphate ester type anionic surfactant (liquid film cracking agent/phosphate ester type anionic surfactant) is more preferably 1.5 or less, still more preferably 1.2 or less, and preferably 0.1 or more, more preferably 0.25 or more, and still more preferably 0.5 or more in terms of mass ratio.

＜32＞

The nonwoven fabric according to any one of the above < 29 > to < 31 >, wherein the phosphate ester type anionic surfactant is any one of alkyl ether phosphate, dialkyl phosphate and alkyl phosphate.

＜33＞

The nonwoven fabric according to < 32 > above, wherein the alkyl phosphate is any one of a substance having a saturated carbon chain such as stearyl phosphate, myristyl phosphate, lauryl phosphate and palmityl phosphate, and a substance having an unsaturated carbon chain such as oleyl alcohol phosphate and palmitoleic acid phosphate and having a side chain in the carbon chain.

＜34＞

The nonwoven fabric according to any one of the above < 1 > to < 33 >, wherein the surface tension of the compound or the liquid film opener is preferably 32mN/m or less, more preferably 30mN/m or less, still more preferably 25mN/m or less, particularly preferably 22mN/m or less, and preferably 1mN/m or more.

＜35＞

The nonwoven fabric according to any one of the above-mentioned < 1 > to < 34 >, wherein the melting point of the compound or the liquid film-splitting agent is preferably 40 ℃ or lower, more preferably 35 ℃ or lower, and the melting point is preferably-220 ℃ or higher, more preferably-180 ℃ or higher.

＜36＞

The nonwoven fabric according to any one of the above-mentioned < 1 > to < 35 >, wherein the distance between fibers of the nonwoven fabric is preferably 150 μm or less, more preferably 90 μm or less, and preferably 50 μm or more, more preferably 70 μm or more.

＜37＞

The nonwoven fabric according to any one of the above-mentioned < 1 > to < 36 >, wherein the fiber fineness of the nonwoven fabric is preferably 3.3dtex or less, more preferably 2.4dtex or less, still more preferably 0.5dtex or more, and still more preferably 1.0dtex or more.

＜38＞

The nonwoven fabric according to any one of the above < 1 > to < 37 > comprising, as the component (B), a polyoxyalkylene-modified polyol fatty acid ester, wherein an alkylene oxide is added to a polyol fatty acid ester which is an esterified product of a polyol and a fatty acid.

＜39＞

The nonwoven fabric according to < 38 > above, wherein the alkylene oxide added to the polyol fatty acid ester is ethylene oxide, propylene oxide or butylene oxide.

＜40＞

The nonwoven fabric according to any one of the above < 1 > to < 39 >, which contains a polyethylene oxide-modified hydrogenated castor oil as the component (B), i.e., a polyoxyalkylene-modified polyol fatty acid ester.

＜41＞

The nonwoven fabric according to any one of the above < 1 > to < 37 >, wherein the anionic surfactant represented by the general formula (S1) as the component (A) is a surfactant in which X is-SO₃M, i.e., the hydrophilic group, is a sulfo group or a salt thereof, more preferably a dialkylsulfonic acid or a salt thereof.

＜42＞

The nonwoven fabric according to any one of the above < 1 > to < 37 >, wherein the anionic surfactant represented by the general formula (S1) as the component (A) is a surfactant in which X is-OSO₃M, i.e. the hydrophilic group being a sulphate group or a salt thereof, moreDialkyl sulfates are preferred.

＜43＞

The nonwoven fabric according to any one of the above < 1 > to < 37 >, wherein the anionic surfactant represented by the above general formula (S1) as the component (A) is an anionic surfactant in which X is-COOM, that is, the hydrophilic group is a carboxyl group or a salt thereof, and a dialkylcarboxylic acid is more preferable.

＜44＞

The nonwoven fabric according to any one of the above < 1 > to < 37 > comprising at least 1 selected from the group consisting of lauryl hydroxysulfobetaine, myristyl hydroxysulfobetaine, palmityl hydroxysulfobetaine and stearyl hydroxysulfobetaine as the component (C), i.e., an amphoteric surfactant having a hydroxysulfobetaine.

＜45＞

The nonwoven fabric according to any one of the above < 1 > to < 44 >, wherein the constituent fibers of the nonwoven fabric comprise heat-fusible fibers, and at least the surfaces of the heat-fusible fibers are formed of a polyolefin resin.

＜46＞

An absorbent article using the nonwoven fabric as described in any one of the above-mentioned < 1 > to < 45 >.

＜47＞

An absorbent article using the nonwoven fabric as described in any one of the above-mentioned < 1 > to < 45 > as a topsheet.

＜48＞

An absorbent article according to the above < 46 > or < 47 >, wherein the absorbent article is a sanitary napkin.

＜49＞

A fiber treatment agent comprising a liquid film-splitting agent and 1 or more selected from the following components (A), (B) and (C), wherein the content of the liquid film-splitting agent is 50% by mass or less,

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 47]

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium. ).

＜50＞

The fiber-treating agent according to the above < 49 >, wherein the water solubility of the liquid film-splitting agent is 0g or more and 0.025g or less.

＜51＞

The fiber-treating agent according to the above < 49 > or < 50 >, wherein the spreading factor of the liquid film-splitting agent with respect to a liquid having a surface tension of 50mN/m is 15 or more.

＜52＞

A fiber treatment agent comprising the following compound and 1 or more selected from the following component (A), component (B) and component (C), wherein the content of the compound is 50% by mass or less,

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 48]

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium).

＜53＞

The fiber-treating agent according to any of the above-mentioned < 49 > to < 52 >, wherein the spreading factor of the compound or the liquid film-splitting agent is more preferably 20mN/m or more, still more preferably 25mN/m or more, and particularly preferably 30mN/m or more.

＜54＞

The fiber-treating agent according to any of the above-mentioned < 49 > to < 53 >, wherein the interfacial tension of the compound or the liquid film-splitting agent with respect to a liquid having a surface tension of 50mN/m is preferably 20mN/m or less, more preferably 17mN/m or less, further preferably 13mN/m or less, further more preferably 10mN/m or less, particularly preferably 9mN/m or less, particularly preferably 1mN/m or less, and more than 0 mN/m.

＜55＞

The fiber-treating agent according to any of the above-mentioned < 49 > to < 54 >, wherein the above-mentioned compound or liquid film-splitting agent preferably contains a modified silicone having a structure having at least one oxygen atom in a modifying group.

＜56＞

The fiber-treating agent according to any of the above-mentioned < 49 > to < 55 >, wherein the above-mentioned compound or the liquid film-splitting agent contains a compound having a siloxane chain in its main chain.

＜57＞

The fiber-treating agent according to any one of the above-mentioned < 49 > to < 56 >, wherein the above-mentioned compound or the liquid film-splitting agent contains a polyoxyalkylene-modified silicone.

＜58＞

The fiber-treating agent according to the above < 57 >, wherein the polyoxyalkylene-modified silicone has at least 1 of polyoxyethylene group, polyoxypropylene group, polyoxybutylene group, and a group obtained by copolymerizing these constituent monomers as the polyoxyalkylene group.

＜59＞

The fiber-treating agent according to the above < 57 > or < 58 >, wherein the number of addition moles of the polyoxyalkylene group of the polyoxyalkylene-modified silicone is preferably 1 or more, more preferably 3 or more, and even more preferably 5 or more, and the number of addition moles is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less.

＜60＞

The fiber-treating agent according to the above < 49 > or < 50 >, wherein the liquid film-splitting agent has a spreading coefficient of more than 0mN/m with respect to a liquid having a surface tension of 50mN/m, and an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50 mN/m.

＜61＞

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

[ chemical formula 49]

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium).

＜62＞

The fiber-treating agent according to < 60 > or < 61 > above, wherein the interfacial tension of the compound or the liquid film-splitting agent with respect to a liquid having a surface tension of 50mN/m is preferably 17mN/m or less, more preferably 13mN/m or less, further preferably 10mN/m or less, particularly preferably 9mN/m or less, particularly preferably 1mN/m or less, and more than 0 mN/m.

＜63＞

The fiber-treating agent according to any of the above-mentioned < 60 > to < 62 >, wherein the spreading factor of the compound or the liquid film-splitting agent is preferably 9mN/m or more, more preferably 10mN/m or more, further preferably 15mN/m or more, and 50mN/m or less, with respect to a liquid having a surface tension of 50 mN/m.

＜64＞

The fiber-treating agent according to any one of the above-mentioned < 60 > to < 63 >, wherein the spreading factor of the compound or the liquid film-breaking agent is 9mN/m or more with respect to a liquid having a surface tension of 50mN/m, the water solubility is 0g or more and 0.025g or less, the interfacial tension with respect to a liquid having a surface tension of 50mN/m is 9mN/m or less, and the surface tension is 32mN/m or less.

＜65＞

The fiber-treating agent according to any of the above-mentioned < 60 > to < 64 >, wherein the water solubility of the compound or the liquid film-splitting agent is preferably 0.0025g or less, more preferably 0.0017g or less, further preferably less than 0.0001g, and preferably 1.0×10^-9g is above.

＜66＞

The fiber-treating agent according to any of the above-mentioned < 60 > to < 65 >, which further comprises a phosphate ester type anionic surfactant.

＜67＞

The fiber-treating agent according to the above < 66 >, wherein the content ratio of the compound or the liquid film-splitting agent to the phosphate-based anionic surfactant (liquid film-splitting agent/phosphate-based anionic surfactant) is 1.8 or less by mass ratio.

＜68＞

The fiber-treating agent according to any one of the above-mentioned < 60 > to < 67 >, wherein the surface tension of the compound or the liquid film-splitting agent is preferably 32mN/m or less, more preferably 30mN/m or less, further preferably 25mN/m or less, particularly preferably 22mN/m or less, and preferably 1mN/m or more.

＜69＞

The fiber-treating agent according to any of the above-mentioned < 60 > to < 68 >, wherein the melting point of the compound or the liquid film-splitting agent is preferably 40 ℃ or lower, more preferably 35 ℃ or lower, and the melting point is preferably-220 ℃ or higher, more preferably-180 ℃ or higher.

[ examples ]

The present invention will be described in further detail below with reference to examples, but the present invention should not be construed as being limited thereto. In the present example, "part(s)" and "%" are based on mass unless otherwise specified. In this section, for convenience, the liquid film breaking agent to be blended in the fiber treatment agent of the example and the dimethylsilicone to be blended in the fiber treatment agent of the comparative example will be collectively referred to as "component (T)".

The surface tension, water solubility and interfacial tension of the liquid film cracking agent and the contact angle of water with respect to the fiber in the following examples were measured by the above-mentioned measuring methods.

(example 1)

(1) Preparation of fiber treatment agent

A base component containing a phosphate ester type anionic surfactant shown below and other components was adjusted to a concentration of 25 wt%, and a compound as a liquid film breaking agent shown below and component (a) were mixed with the base component by stirring to adjust a desired balance, and then diluted with water to prepare a diluted solution for coating on fibers. The "base component" is a component that imparts a basic function as a conventional fiber treatment agent, such as emulsion stability of the agent, processability of the nonwoven fabric, and hydrophilicity (initial hydrophilicity and durable hydrophilicity). These do not have the characteristics of the liquid film cracking agents of the present invention. For example, the following other component (i) has water solubility to such an extent that suspension, precipitation, or precipitation is not observed even when about 10g is dissolved in 100g of deionized water.

The content ratio of the liquid film cracking agent to the phosphate ester type anionic surfactant (liquid film cracking agent/phosphate ester type anionic surfactant) was set to 0.45.

Component (T): liquid film cracking agent

Polyethylene Oxide (POE) modified dimethyl Silicone 10.0% by mass

(KF-6015, manufactured by shin-Etsu chemical Co., Ltd.)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Anionic interfacial agent of phosphate type:

potassium alkyl phosphate 22.2% by mass

Other components:

(i) water-soluble Polyethylene Oxide (POE) Polypropylene Oxide (POP) modified silicone

17.8% by mass

(ii) Polyethylene Oxide (POE) alkylamide 26.7% by mass

(iii) Stearyl betaine 13.3% by mass

In the structure X-Y, Polyethylene Oxide (POE) modified dimethyl silicone in which X comprises a dimethylpolysiloxane chain containing-Si (CH3)2O-, Y comprises a POE chain containing- (C2H4O) -, the terminal group of the POE chain is methyl (CH3), the modification ratio is 20%, the addition mole number of Polyoxyalkylene (POA) is 3, and the mass average molecular weight is 4000 is used as the liquid film cracking agent.

The spreading factor of Polyethylene Oxide (POE) -modified dimethyl silicone as a liquid film opener with respect to a liquid having a surface tension of 50mN/m was 28.8mN/m, the surface tension of Polyethylene Oxide (POE) -modified dimethyl silicone was 21.0mN/m, the interfacial tension of Polyethylene Oxide (POE) -modified dimethyl silicone with respect to a liquid having a surface tension of 50mN/m was 0.2mN/m, and the water solubility was less than 0.0001 g. These values were measured by the measurement methods described above. In this case, as the "liquid having a surface tension of 50 mN/m", a solution prepared by adding 3.75. mu.L of polyoxyethylene sorbitan monolaurate (product name: RHEODOL SUPER TW-L120, manufactured by Kao corporation) as a nonionic surface active substance to 100g of deionized water using a micropipette (ACURA825, manufactured by Socorex Isba SA) was used, and the surface tension was adjusted to 50. + -. 1 mN/m. The water solubility was measured by adding 0.0001g of the agent per one time. As a result, it was observed that 0.0001g was not dissolved and 0.0001g was not dissolved, and that 0.0001g was dissolved and 0.0002g was not dissolved and was 0.0001 g. Other values were also measured by the same method.

(2) Preparation of sample of nonwoven Fabric of example 1

A sample of the uneven nonwoven fabric shown in fig. 14 was produced by the method shown in fig. 15. Specifically, a web was formed using a thermal fusion core-sheath type composite fiber (fineness 2.2dtex, core component PET, sheath component PE (polyethylene)) using a carding machine, and the web was embossed. The embossing was performed so that a lattice-shaped embossed portion was formed and the area ratio of the embossed portion (compressed portion) was 22%. The embossing temperature was 110 ℃. Then hot air processing is carried out. The hot air processing is a heat treatment in which hot air is blown from the embossing surface side in the embossing processing 1 time. The heat treatment temperature for hot air processing was set at 136 ℃.

The obtained hydrophilic nonwoven fabric has a thin portion (embossed portion) 68 and other thick portions as shown in FIG. 14The thick portion 69 has a concave-convex surface with large undulations on the 1 st surface 1A side having the convex portions 61 and the concave portions 62, and a substantially flat surface on the 2 nd surface 1B side. The basis weight of the nonwoven fabric was 30g/cm²。

The fiber to be used is coated with a diluent of the fiber treatment agent in advance before the nonwoven fabric is produced. In this coating method, the fiber is immersed in the above-mentioned diluted solution of the fiber treatment agent and dried.

The deposition amount (OPU) of the fiber treatment agent to the mass of the fiber was set to 0.45 mass%.

(example 2)

The fiber treatment agent used in example 2 was prepared in the same manner as in example 1 except that the blending ratio of each component used in example 1 was as follows, and the nonwoven fabric sample of example 2 was prepared in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 2 was set to 1.03. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.43 mass%.

Component (T): liquid film cracking agent

Polyethylene Oxide (POE) modified dimethyl Silicone 20.0% by mass

(KF-6015, manufactured by shin-Etsu chemical Co., Ltd.)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 19.4% by mass

Other components:

15.6% by mass

(ii) Polyethylene Oxide (POE) alkylamide 23.3% by mass

(iii) Stearyl betaine 11.7% by mass

(example 3)

The fiber treatment agent used in example 2 was prepared in the same manner as in example 1 except that the blending ratio of each component used in example 1 was set as follows, and the nonwoven fabric sample of example 3 was produced in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 3 was set to 1.80. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.44 mass%.

Component (T): liquid film cracking agent

Polyethylene Oxide (POE) modified dimethyl Silicone 30.0% by mass

(KF-6015, manufactured by shin-Etsu chemical Co., Ltd.)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate 16.7% by mass

Other components:

13.3% by mass

(ii) Polyethylene Oxide (POE) alkylamide 20.0 mass%

(iii) Stearyl betaine 10.0% by mass

(example 4)

The fiber treatment agent used in example 2 was prepared in the same manner as in example 1 except that the blending ratio of each component used in example 1 was set as follows, and the nonwoven fabric sample of example 4 was produced in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 4 was set to 2.88. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.48 mass%.

Component (T): liquid film cracking agent

Polyethylene Oxide (POE) modified dimethyl Silicone 40.0% by mass

(KF-6015, manufactured by shin-Etsu chemical Co., Ltd.)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 13.9% by mass

Other components:

11.1% by mass

(ii) Polyethylene Oxide (POE) alkylamide 16.7% by mass

(iii) Stearyl betaine 8.3% by mass

(example 5)

(1) Preparation of fiber treatment agent

The fiber treatment agent used in example 5 was prepared in the same manner as in example 1 except that the following components and blending ratios were set, and the nonwoven fabric sample of example 5 was produced in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 5 was set to 1.03. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.41 mass%.

Component (T): liquid film cracking agent

Polyoxypropylene (POP) modified Dimethicone 20.0% by mass

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 19.4% by mass

Other components:

15.6% by mass

(ii) Polyethylene Oxide (POE) alkylamide 23.3% by mass

(iii) Stearyl betaine 11.7% by mass

A polyoxypropylene (POP) modified dimethylsilicone (obtained by hydrosilation of a silicone oil and a hydrocarbon compound) as a liquid film cracking agent, wherein X in the prepared structure X-Y contains a dimethylpolysiloxane chain containing-Si (CH)₃)₂O-, Y comprises a POP chain comprising- (C)₃H₆O) -, the terminal group of POP chain is methyl (CH)₃) The modification ratio was 20%, the number of moles of Polyoxyalkylene (POA) added was 3, and the mass average molecular weight was 4150.

The spreading coefficient of polyoxypropylene (POP) -modified dimethyl silicone as a liquid film opener with respect to a liquid having a surface tension of 50mN/m was 25.4mN/m, the surface tension of polyoxypropylene (POP) -modified dimethyl silicone was 21.0mN/m, the interfacial tension of polyoxypropylene (POP) -modified dimethyl silicone with respect to a liquid having a surface tension of 50mN/m was 3.6mN/m, and the water solubility was less than 0.0001 g.

(example 6)

(1) Preparation of fiber treatment agent

The fiber treatment agent used in example 6 was prepared in the same manner as in example 1 except that the following components and blending ratios were set, and the nonwoven fabric sample of example 6 was produced in the same manner as in example 1.

Component (T): liquid film cracking agent

Polyoxypropylene (POP) modified Dimethicone 20.0% by mass

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 19.4% by mass

Other components:

15.6% by mass

(ii) Polyethylene Oxide (POE) alkylamide 23.3% by mass

(iii) Stearyl betaine 11.7% by mass

A polyoxypropylene (POP) -modified dimethyl silicone (obtained by subjecting a silicone oil and a hydrocarbon compound to a hydrosilation reaction) as a liquid film cracking agent, wherein X in the structure X-Y comprises a dimethyl polysiloxane chain comprising-Si (CH)₃)₂O-, Y comprises a POP chain comprising- (C)₃H₆O) -, the terminal group of POP chain is methyl (CH)₃) The modification ratio was 10%, the number of moles of Polyoxyalkylene (POA) added was 10, and the mass average molecular weight was 4340.

The spreading coefficient of polyoxypropylene (POP) -modified dimethyl silicone as a liquid film-splitting agent with respect to a liquid having a surface tension of 50mN/m was 26.9mN/m, the surface tension of polyoxypropylene (POP) -modified dimethyl silicone was 21.5mN/m, the interfacial tension of polyoxypropylene (POP) -modified dimethyl silicone with respect to a liquid having a surface tension of 50mN/m was 1.6mN/m, and the water solubility was 0.0002 g.

(example 7)

The fiber treatment agent used in example 7 was prepared in the same manner as in example 1 except that the following components and blending ratios were set, and the nonwoven fabric sample of example 7 was produced in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 7 was set to 1.03. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.45 mass%.

Component (T): liquid film cracking agent

Caprylic/capric triglyceride 20.0% by mass

(COCONAD MT manufactured by Kao corporation)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 19.4% by mass

Other components:

15.6% by mass

(ii) Polyethylene Oxide (POE) alkylamide 23.3% by mass

(iii) Stearyl betaine 11.7% by mass

Caprylic capric triglyceride (COCONAD MT manufactured by Kao corporation) as a liquid film-splitting agent, Z in the structure Z-Y is-O-CH (CH)₂O-*)₂(indicates a bonding part), Y is C₈H₁₅O-or C₁₀H₁₉Of hydrocarbon chains of O-The fatty acid composition of the substance comprises 82% of caprylic acid and 18% of capric acid, and the substance has a mass-average molecular weight of 550.

The spreading factor of caprylic/capric triglyceride as a liquid film opener with respect to a liquid having a surface tension of 50mN/m is 8.8mN/m, the surface tension of caprylic/capric triglyceride is 28.9mN/m, the interfacial tension of caprylic/capric triglyceride with respect to a liquid having a surface tension of 50mN/m is 12.3mN/m, and the water solubility is less than 0.0001 g.

(example 8)

The fiber treatment agent used in example 8 was prepared in the same manner as in example 1 except that the following components and blending ratios were set, and the nonwoven fabric sample of example 8 was produced in the same manner as in example 1.

The content ratio of the liquid film-splitting agent to the phosphate ester type anionic surfactant (liquid film-splitting agent/phosphate ester type anionic surfactant) in the fiber-treating agent of example 8 was set to 1.03. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.46 mass%.

Component (T): liquid film cracking agent

20.0% by mass of polypropylene glycol

(antifoaming agent No.1 manufactured by Kao corporation)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 19.4% by mass

Other components:

15.6% by mass

(ii) Polyethylene Oxide (POE) alkylamide 23.3% by mass

(iii) Stearyl betaine 11.7% by mass

As the liquid film-splitting agent, polypropylene glycol (antifoaming agent No.1 manufactured by Kao corporation) was used, in which X in the structure X was a POP chain-containing material, the number of addition mols of Polyoxyalkylene (POA) was 52, and the mass-average molecular weight was 3000.

The spreading coefficient of polypropylene glycol as a liquid film opener with respect to a liquid having a surface tension of 50mN/m was 16.3mN/m, the surface tension of polypropylene glycol was 32.7mN/m, the interfacial tension of polypropylene glycol with respect to a liquid having a surface tension of 50mN/m was 1.0mN/m, and the water solubility was less than 0.0001 g.

(example 9)

A nonwoven fabric sample of example 9 was produced in the same manner as in example 2, except that 10.0 mass% of the Polyethylene Oxide (POE) (addition mole number 60) modified polyol fatty acid ester as the component (B) was used instead of 10.0 mass% of the component (a) used in example 2, and the amount of the fiber treatment agent adhering to the mass of the fibers (OPU) was set to 0.49 mass%.

(example 10)

The fiber treatment agent used in example 10 was prepared in the same manner as in example 1 except that the following components and blending ratios were set, and the nonwoven fabric sample of example 10 was produced in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 10 was set to 0.96. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.43 mass%.

Component (T): liquid film cracking agent

Polyethylene Oxide (POE) modified dimethyl Silicone 20.0% by mass

(KF-6015, manufactured by shin-Etsu chemical Co., Ltd.)

Component (C):

alkyl hydroxy sulfobetaine acid 5.0% by mass

Phosphate type anionic surfactant:

potassium alkyl phosphate 20.8% by mass

Other components:

16.7% by mass

(ii) Polyethylene Oxide (POE) alkylamide 25.0 mass%

(iii) Stearyl betaine 12.5% by mass

(example 11)

The fiber treatment agent used in example 7 was prepared in the same manner as in example 1 except that the following components and blending ratios were set, and the nonwoven fabric sample of example 11 was produced in the same manner as in example 1.

The content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant (liquid film splitting agent/phosphate ester type anionic surfactant) in the fiber treatment agent of example 11 was set to 1.03. The deposition amount (OPU) of the fiber treatment agent to the fiber mass was set to 0.43 mass%.

Component (T): liquid film cracking agent

20.0% by mass of liquid isoparaffin

(Luvitol Lite, manufactured by BASF Japan K.K.)

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 19.4% by mass

Other components:

15.6% by mass

(ii) Polyethylene Oxide (POE) alkylamide 23.3% by mass

(iii) Stearyl betaine 11.7% by mass

As the liquid isoparaffin (Luvitol Lite, manufactured by BASF Japan) as a liquid film cracking agent, a substance having a mass average molecular weight of 450 was used.

The spreading coefficient of the liquid isoparaffin as a liquid film cracking agent with respect to a liquid having a surface tension of 50mN/m was 14.5mN/m, the surface tension of the liquid isoparaffin was 27.0mN/m, the interfacial tension of the liquid isoparaffin with respect to a liquid having a surface tension of 50mN/m was 8.5mN/m, and the water solubility was less than 0.0001 g.

(example 12)

A nonwoven fabric sample of example 12 was produced in the same manner as in example 2, except that 10g of ditridecylsulfosuccinic acid was contained as the component (a) and the amount of adhesion of the fiber treatment agent (OPU) to the mass of the fibers was 0.42 mass%. In this case, the components (B) and (C) are not contained.

(example 13)

A nonwoven fabric sample of example 13 was produced in the same manner as in example 9, except that the components (a) and (C) were not contained, 10g of POE (addition mole number 25) modified polyol fatty acid ester was contained as the component (B), and the amount of adhesion (OPU) of the fiber treatment agent to the mass of the fibers was set to 0.46 mass%.

(example 14)

The nonwoven fabric sample of example 14 was produced in the same manner as in example 2 except that 5g of dioctyl sulfosuccinic acid was contained as component (a), 5g of POE (addition mole number 60) modified polyol fatty acid ester was contained as component (B), component (C) was not contained, and the amount of adhesion (OPU) of the fiber treatment agent to the fiber mass was set to 0.41 mass%.

(example 15)

The nonwoven fabric sample of example 15 was produced in the same manner as in example 2 except that the nonwoven fabric sample contained no component (a), 5g of POE (addition mole number 60) modified polyol fatty acid ester as component (B), 5g of alkylhydroxysulfobetaine acid as component (C), and the amount of adhesion (OPU) of the fiber treatment agent to the fiber mass was 0.40 mass%.

(example 16)

The nonwoven fabric sample of example 16 was produced in the same manner as in example 5, except that the components other than the liquid film splitting agent were set to be the following, the content ratio of the liquid film splitting agent to the phosphate ester type anionic surfactant in the fiber treatment agent (liquid film splitting agent/phosphate ester type anionic surfactant) was set to 1.11, and the amount of adhesion (OPU) of the fiber treatment agent to the fiber mass was set to 0.45 mass%.

Phosphate type anionic surfactant:

alkyl phosphate potassium salt 18.0% by mass

Component (A):

dialkyl sulfosuccinic acid 5.0% by mass

Component (B):

POE (addition mol number 60) modified polyol fatty acid ester 5.0% by mass

Component (C):

alkyl hydroxy sulfobetaine acid 5.0% by mass

Other components:

14.5% by mass

(ii) Polyethylene Oxide (POE) alkylamide 21.6% by mass

(iii) Stearyl betaine 10.9% by mass

Comparative example 1

A nonwoven fabric sample of comparative example 1 was produced in the same manner as in example 1, except that the liquid surface cracking agent was not contained, the fiber treatment agent was used at the following compounding ratio, and the amount of adhesion (OPU) of the fiber treatment agent to the mass of the fiber was 0.46 mass%.

Component (A):

10.0% by mass of dialkylsulfosuccinic acid

Phosphate type anionic surfactant:

potassium alkyl phosphate 25.0% by mass

Other components:

20.0% by mass

(ii) Polyethylene Oxide (POE) alkylamide 30.0 mass%

(iii) Stearyl betaine 15.0% by mass

Comparative example 2

A nonwoven fabric sample of comparative example 2 was produced in the same manner as in example 1, except that the liquid surface cracking agent was not contained, the fiber treatment agent was used at the following compounding ratio, and the amount of adhesion (OPU) of the fiber treatment agent to the mass of the fiber was 0.42 mass%.

Component (B):

polyethylene Oxide (POE) (addition mol number 60) modified polyol fatty acid ester 10.0% by mass

Phosphate type anionic surfactant:

potassium alkyl phosphate 25.0% by mass

Other components:

20.0% by mass

(ii) Polyethylene Oxide (POE) alkylamide 30.0 mass%

(iii) Stearyl betaine 15.0% by mass

Comparative example 3

A nonwoven fabric sample of comparative example 3 was produced in the same manner as in example 1, except that the liquid surface cracking agent was not contained, the fiber treatment agent was used at the following compounding ratio, and the amount of adhesion (OPU) of the fiber treatment agent to the mass of the fiber was 0.44 mass%.

Component (C):

alkyl hydroxy sulfobetaine acid 5.0% by mass

Phosphate type anionic surfactant:

potassium alkyl phosphate salt 26.4% by mass

Other components:

21.1% by mass

(ii) Polyethylene Oxide (POE) alkylamide 31.7% by mass

(iii) Stearyl betaine 15.8% by mass

Comparative example 4

The nonwoven fabric sample of comparative example 4 was produced in the same manner as in example 1 except that 10 mass% of simethicone (KF-96A-100 cs manufactured by shin-Etsu chemical Co., Ltd.) which is not a liquid film cracking agent and is not modified with a hydrophilic polyoxyalkylene group, a hydroxyl group or the like was blended as a component of the fiber treatment agent, and the amount of adhesion (OPU) of the fiber treatment agent to the mass of the fiber was set to 0.42 mass%.

The spreading factor of the above-mentioned dimethylsilicone oil with respect to a liquid having a surface tension of 50mN/m was 2.4mN/m, the surface tension of the dimethylsilicone oil was 21.0mN/m, the interfacial tension of the dimethylsilicone oil with respect to a liquid having a surface tension of 50mN/m was 26.6mN/m, and the water solubility was 0.0001 g.

Comparative example 5

The nonwoven fabric sample of comparative example 5 was produced in the same manner as in example 2 except that 20 mass% of simethicone (KF-96A-100 cs manufactured by shin-Etsu chemical Co., Ltd.) which is not a liquid film cracking agent was prepared as a component of the fiber treatment agent and the content ratio (OPU) of the fiber treatment agent to the mass of the fiber was set to 0.41 mass%.

(reference example)

A sample of the nonwoven fabric of the reference example was produced in the same manner as in example 1 except that the fiber-treating agent was used in an amount of 20 mass% in the Polyethylene Oxide (POE) modified dimethyl silicone (KF-6015, manufactured by shin-shikoku chemical corporation) in example 1, and the components (a) to (C) were not contained, and the amounts of the anionic surfactant of phosphate ester and the other components (i) to (iii) were prepared in the same manner as in example 1, and the content ratio (OPU) of the fiber-treating agent to the mass of the fiber was set to 0.43 mass%.

(measurement of contact Angle)

Based on the above (method for measuring contact angle), fibers were taken out from the top of the convex portion and the flat surface on the back side thereof of the obtained samples of examples and comparative examples, and the contact angle of water with respect to the fibers was measured. The contact angles of 2 different sites were measured for 1 fiber taken out. The contact angle was measured until the contact angle was 1 decimal point or less, and the value obtained by averaging the measured values of 10 total positions (rounded at the 2 nd position or less) was defined as the contact angle.

(evaluation)

The following evaluations were carried out by removing a topsheet from a sanitary napkin (manufactured by Kao corporation, trade name "Laurier clean absorbing and softening daily sanitary napkin", manufactured in 2015) as an example of an absorbent article, laminating samples of the nonwoven fabrics of the examples and comparative examples in place of the topsheet, fixing the periphery of the laminated samples to obtain sanitary napkins for evaluation, and using the sanitary napkins for evaluation thus obtained.

(residual liquid amount of surface sheet (nonwoven fabric test piece))

An acrylic plate having a through hole with an inner diameter of 1cm was superposed on the surface of each sanitary napkin for evaluation, and a fixed load of 100Pa was applied to the sanitary napkin. Under this load, 6.0g of horse blood (horse blood prepared by adjusting horse defibrinated blood produced by Baiotesuto research corporation, Japan to 8.0 cP) was allowed to flow through the through-holes of the acrylic plate. The horse blood used was adjusted at 30rpm using a TVB10 model viscometer available from Toyobo industries. When horse blood is left to stand, a portion having a high viscosity (red blood cells and the like) is precipitated, a portion having a low viscosity (plasma) remains as a supernatant, and the mixing ratio of the portion is adjusted so as to be 8.0 cP. The acrylic plate was removed 60 seconds after the flow of 6.0g in total of defibered horse blood. Then, the mass (W2) of the nonwoven fabric test piece was measured, and the difference (W2-W1) from the mass (W1) of the nonwoven fabric test piece before the horse blood was introduced was calculated. The above operation was performed 3 times, and the average of the 3 times was defined as the liquid residual amount (mg). The liquid residual amount is an index of how much the skin of the wearer is wet, and the smaller the liquid residual amount is, the better the result is.

(moisture reverse amount of surface sheet)

An acrylic plate having a through hole with an inner diameter of 1cm was superposed on the surface of each sanitary napkin for evaluation, and a fixed load of 100Pa was applied to the sanitary napkin. Under the load, defibrinated horse blood was allowed to flow into the acrylic plate through the permeation holes in an amount of 9.0g in total so that defibrinated horse blood was allowed to flow into 3.0g at 3 minute intervals. After 300 seconds from the inflow of horse blood, the acrylic plate was removed, and then a toilet paper was superimposed on the surface of the nonwoven fabric, and a pressure plate was further superimposed on the toilet paper, thereby applying a load of 2000Pa to the sanitary napkin. The weight (W4) of the toilet paper was measured 5 seconds after the platen was superimposed, and the difference (W4-W3) between the weight (W3) of the toilet paper and the weight of the toilet paper before the toilet paper was superimposed on the surface of the nonwoven fabric was calculated. The above operation was performed 3 times, and the average value of the 3 times was defined as the back-liquid amount (also referred to as the back-moisture amount) (mg), and the lower the back-moisture amount, the more difficult the back-liquid generation and the higher the evaluation.

(surface liquid flow amount of surface sheet)

The adhesive was cured by cold spray, and the top sheet was taken out from a sanitary napkin (trade name "Laurier clean absorbent sanitary napkin without flaps", manufactured in 2015) commercially available from kao corporation, and the hydrophilic nonwoven fabrics of the examples and comparative examples were laminated instead of the top sheet, and the periphery thereof was fixed to obtain a sanitary napkin for evaluation. Each nonwoven fabric is disposed with the back surface side (2 nd surface side) facing the absorbent body side.

The test apparatus used a device having a mounting portion in which the mounting surface of the sanitary napkin was inclined at 45 ° to the horizontal plane. The sanitary napkin is placed on the placing portion such that the surface sheet material faces upward. Colored deionized water as a test liquid was dropped onto the sanitary napkin at a rate of 1g/10 sec. The distance from the position where the nonwoven fabric was first wetted to the position where the test liquid was first absorbed by the absorbent body was measured. The above operation was performed 3 times, and the average of the 3 times was set as a liquid flow distance (mm). The liquid flow distance is an index of the amount of liquid that is not absorbed by the sanitary napkin and comes into contact with the skin of the wearer, and the shorter the liquid flow distance, the higher the evaluation.

The constituent compositions of the examples and comparative examples, and the results of the measurements and evaluations of the examples and comparative examples are shown in tables 1 to 3 below.

[ Table 1]

[ Table 2]

[ Table 3]

As shown in tables 1 to 3, in examples 1 to 10, the residual liquid amount and the moisture content of the surface sheet were suppressed and the low residual liquid performance and the low liquid returning performance were both satisfied as compared with comparative examples 1 to 3 having no liquid film cracking agent. It is understood that the examples 1 to 8 have a large hydrophilic gradient compared to comparative example 1, and that the oil-soluble liquid film cracking agent (POE-modified silicone or POP-modified silicone) acts on the component (a) to increase the hydrophilic gradient. In this regard, the same applies to the case of comparing examples 9 and 10 having the component (B) or the component (C) with comparative examples 2 and 3. Therefore, in examples 1 to 10, the liquid film action of the liquid film cracking agent and the liquid suction action by the hydrophilicity gradient are exhibited by the combination of the liquid film cracking agent and any of the components (a) to (C), and the liquid retention property and the liquid returning property are more excellent than in comparative examples 1 to 3 without significantly deteriorating the liquid fluidity. Among the components (a), (B) and (C), the component (B) is most excellent in performance, and expansion of the hydrophilicity gradient and improvement in performance have been confirmed. The component (C) has a smaller gradient in hydrophilicity, but is superior in liquid fluidity to the case of using the component (A). On the other hand, in comparative examples 1 to 3, since the fiber treatment agent containing only the combination of the above-described base component and any one of the components (a) to (C) was used without the liquid film cracking agent, sufficient performance as in the examples could not be obtained.

Further, examples 1 to 8 using the liquid film breaking agent having a large spreading factor and the component (a) suppressed the liquid residual amount and the moisture content to be small, and achieved both low-liquid residual performance and low-liquid-returning performance, as compared with comparative example 4 using dimethylpolysiloxane having a small spreading factor and the component (a). Further, examples 1 to 8 suppressed the liquid residual amount, and preferably suppressed the amount of moisture reversal, as compared with comparative example 5 in which dimethylpolysiloxane having a smaller spreading factor was set to 20 mass%.

Otherwise, the difference in contact angle (convex top P1-back P2) was larger in examples 1 to 4, 9 and 10 compared with the reference example which did not contain any of the components (a) to (C) although the same liquid film cracking agent was used, and the amount of remaining liquid and the amount of moisture back were suppressed. Namely, the liquid film cracking agent and the hydrophilic degree gradient have synergistic effect, so that the low liquid residue performance and the low liquid return performance can be considered at the same time.

Further, in examples 1 to 4, the amount of the liquid remaining and the amount of moisture back were reduced as the amount of the liquid film cracking agent added was increased. That is, it is considered that the liquid film cracking action is more strongly exerted with an increase in the amount of the liquid film cracking agent. Further, from the results of examples 1 to 3 and 4, it is found that if the oil-soluble liquid film cracking agent having a hydrophilic group properly controlled is excessively added, the liquid fluidity of the surface (the 1 st surface 1A side) is deteriorated, and the addition is more preferably less than 40%. Further, it is considered that the liquid fluidity is affected by the oil solubility of the liquid film-breaking agent. However, examples 1 to 10 can preferably control the surface liquid fluidity, compared to comparative examples 4 and 5 having dimethyl silicone with a smaller spreading coefficient, by preferably controlling the hydrophilic group of the liquid film cleavage agent.

Further, in example 12, when di-tridecyl sulfosuccinic acid having a longer alkyl chain was added instead of the dialkyl (dioctyl) sulfosuccinic acid used in the other examples, the degree of hydrophilicity gradient was substantially the same, but the top portion was further made less hydrophilic, and the liquid return suppression performance was better than that of the comparative example.

Further, it is found that example 9 in which POE (addition mole number 60) modified polyol fatty acid ester was used, that is, modified polyol fatty acid ester having a long POE chain, the top side was made hydrophilic and the liquid flow distance was made shorter than example 13 in which POE (addition mole number 25) modified polyol fatty acid ester was used.

It is found that example 14, in which 5% of each of dialkyl (dioctyl) sulfosuccinic acid and POE (addition mole number 60) modified polyol fatty acid ester was blended, exhibited a hydrophilic gradient in the same manner as in examples 2 and 9 in which 10% of each was blended alone, and exhibited better liquid residue suppression performance and liquid return suppression performance than the comparative examples.

It is found that example 15, in which an alkylhydroxysulfobetaine and a POE (addition mole number 60) modified polyol fatty acid ester were blended at 5% each, exhibited a hydrophilic gradient in the same manner as in examples 9 and 10 in which each was blended at 10%, and exhibited better liquid residue suppression performance and liquid return suppression performance than the comparative examples.

It is understood that in example 16, although 5% of each of the alkyl dialkyl (dioctyl) sulfosuccinate, the hydroxysultaine, and the POE (addition mole number 60) modified polyol fatty acid ester was blended, the hydrophilicity gradient was exhibited in the same manner as in examples 2, 9, and 10, in which each was blended separately, and the liquid residue suppression performance and the liquid return suppression performance were better than those in comparative examples.

The present invention has been described in connection with the embodiments and examples thereof, but the present invention is not limited by any of the details of the description so long as the inventors do not particularly specify, and it is considered that the present invention should be construed broadly without departing from the spirit and scope of the invention as set forth in the appended claims.

The present application claims priority based on japanese patent application 2015-244863 filed in japan on 12/16/2015, which is hereby incorporated by reference as part of the description of the present specification.

Description of the symbols

1 fiber

2 liquid film

3 liquid film cracking agent

10. 20, 30, 40, 50, 60, 70, 100, 101, 102, 103 non-woven fabric

Claims

1. A nonwoven fabric having a fiber-treating agent adhered thereto, the fiber-treating agent comprising a liquid film-splitting agent and 1 or more selected from the following components (A), (B) and (C),

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

Wherein Z represents a group having a valence of 3 and selected from the group consisting of a linear or branched alkyl chain having 1 to 12 carbon atoms and optionally containing an ester group, an amide group, an amine group, a polyoxyalkylene group, an ether group and a double bond,

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium,

the number of moles of alkylene oxide(s) forming the component (B) added to the polyol fatty acid ester forming the component (B) is 60 to 80 moles,

the liquid film cleavage agent is an agent having 1 or more selected from the group consisting of,

a compound having a spreading coefficient of 15mN/m or more with respect to a liquid having a surface tension of 50mN/m and a water solubility of 0g or more and 0.025g or less, and

a compound having a spreading coefficient of more than 0mN/m with respect to a liquid having a surface tension of 50mN/m, a water solubility of 0g or more and 0.025g or less, and an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50 mN/m.

2. The nonwoven fabric according to claim 1, which comprises the liquid film-splitting agent and the component (A), wherein the liquid film-splitting agent has a mass average molecular weight of 10000 or less.

3. The nonwoven fabric according to claim 1, which contains the liquid film-splitting agent and the component (B),

the nonwoven fabric has a 1 st surface side and a 2 nd surface side opposite to the 1 st surface side, and fibers having a smaller contact angle than the fibers on the 1 st surface side are arranged on the 2 nd surface side.

4. A nonwoven fabric comprising the following compound and 1 or more selected from the following component (A), component (B) and component (C),

the compound is 1 or more selected from the following compounds: a compound having a spreading coefficient of 15mN/m or more with respect to a liquid having a surface tension of 50mN/m and a water solubility of 0g or more and 0.025g or less, and

a compound having a spreading coefficient of more than 0mN/m with respect to a liquid having a surface tension of 50mN/m, a water solubility of 0g or more and 0.025g or less, and an interfacial tension of 20mN/m or less with respect to a liquid having a surface tension of 50mN/m,

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium,

the number of moles of alkylene oxide(s) forming the component (B) added to the polyol fatty acid ester forming the component (B) is 60 to 80 moles.

5. The nonwoven fabric according to any one of claims 1 to 4,

the compound or the liquid film cracking agent comprises 1 or more selected from the following compounds,

a compound having at least 1 structure selected from the following structures X, X-Y and Y-X-Y and a compound having at least 1 structure selected from the following structures Z, Z-Y and Y-Z-Y,

structure X represents: > C (A) -, -C (A)₂-、-C(A)(B)-、＞C(A)-C(R¹)＜、＞C(R¹)-、-C(R¹)(R²)-、-C(R¹)₂-, > C < and, -Si (R)¹)₂O-、-Si(R¹)(R²) A siloxane chain having a repeating arbitrary basic structure or a combination of 2 or more structures in O-, or a mixed chain thereof,

Structure X has a hydrogen atom at the terminus or is selected from-C (A)₃、-C(A)₂B、-C(A)(B)₂、-C(A)₂-C(R¹)₃、-C(R¹)₂A、-C(R¹)₃And, and-OSi(R¹)₃、-OSi(R¹)₂(R²)、-Si(R¹)₃、-Si(R¹)₂(R²) At least 1 group selected from the group consisting of,

c represents a carbon atom, and <, > and-represent a bonding bond,

a plurality of R are respectively present in the structure X¹、R²A, B, which may be the same or different from each other,

y represents a hydrophilic group having hydrophilicity and containing an atom selected from the group consisting of a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a phosphorus atom and a sulfur atom, and Y is the same or different from each other when plural,

structure Z represents: > C (A) -, -C (A)₂-、-C(A)(B)-、＞C(A)-C(R³)＜、＞C(R³)-、-C(R³)(R⁴)-、-C(R³)₂A hydrocarbon chain having a repeating structure of any basic structure of-C or > C < or a combination of 2 or more structures,

having a hydrogen atom at the end of structure Z, or selected from-C (A)₃、-C(A)₂B、-C(A)(B)₂、-C(A)₂-C(R³)₃、-C(R³)₂A、-C(R³)₃At least 1 group selected from the group consisting of,

said C represents a carbon atom, and the compound is represented by,

A. each B independently represents a substituent containing an oxygen atom or a nitrogen atom.

6. The nonwoven fabric according to claim 5, which contains the compound and the component (C).

7. The nonwoven fabric according to claim 5, which contains the compound having a mass average molecular weight of 10000 or less and the component (A).

8. The nonwoven fabric according to claim 5, which contains the compound and the component (B),

9. The nonwoven fabric according to any one of claims 1 to 4,

the compound or the liquid film cracking agent contains a compound having a siloxane chain in the main chain.

10. The nonwoven fabric according to any one of claims 1 to 4,

the compound or the liquid film cracking agent contains polyoxyalkylene-modified silicone.

11. The nonwoven fabric according to claim 10, wherein,

the polyoxyalkylene-modified silicone has a molar number of addition of the polyoxyalkylene group of 3 to 10.

12. The nonwoven fabric according to any one of claims 1 to 4,

the distance between fibers of the nonwoven fabric is 50 to 150 μm.

13. The nonwoven fabric according to any one of claims 1 to 4,

the fineness of the fibers of the nonwoven fabric is 0.5dtex or more and 3.3dtex or less.

14. The nonwoven fabric according to any one of claims 1 to 4,

the nonwoven fabric has a 1 st surface side and a 2 nd surface side opposite to the 1 st surface side, and the contact angle of the fibers on the 1 st surface side is 70 degrees or more and 85 degrees or less.

15. The nonwoven fabric according to any one of claims 1 to 4,

the nonwoven fabric has a 1 st surface side and a 2 nd surface side opposite to the 1 st surface side, and the difference in contact angle between the fibers on the 1 st surface side and the fibers on the 2 nd surface side is 2 degrees or more and 65 degrees or less.

16. The nonwoven fabric according to any one of claims 1 to 4,

the nonwoven fabric has a 1 st surface side and a 2 nd surface side opposite to the 1 st surface side,

the 1 st surface side has a convex portion, and the 2 nd surface side is provided with a fiber having a smaller contact angle than a top fiber of the convex portion.

17. The nonwoven fabric according to any one of claims 1 to 4,

The 1 st surface side has a convex portion, and the difference in contact angle between the fibers at the top of the convex portion and the fibers on the 2 nd surface side is 3 degrees or more and 25 degrees or less.

18. An absorbent article using the nonwoven fabric according to any one of claims 1 to 17.

19. An absorbent article using the nonwoven fabric according to any one of claims 1 to 17 as a topsheet.

20. The absorbent article of claim 18 or 19, wherein the absorbent article is a sanitary napkin.

21. A fiber treatment agent comprising a liquid film-splitting agent and 1 or more selected from the following component (A), component (B) and component (C), wherein the content of the liquid film-splitting agent is 50% by mass or less,

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

X represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium,

22. The fiber-treating agent according to claim 21, for imparting liquid film splitting property to fibers.

23. A fiber treatment agent comprising the following compound and 1 or more selected from the following component (A), component (B) and component (C), wherein the content of the compound is 50% by mass or less,

Component (B): polyoxyalkylene-modified polyol fatty acid ester

Component (C): amphoteric surfactants having hydroxysulfobetaine groups

x represents-SO₃M、-OSO₃M or-COOM, wherein the group is,

m represents H, Na, K, Mg, Ca or ammonium,

24. The fiber treatment agent according to claim 23, which contains the compound with the component (C).

25. The fiber-treating agent according to claim 23, which comprises the compound and the component (a), and the compound has a mass-average molecular weight of 10000 or less.

26. The fiber treatment agent according to claim 23, comprising the compound and the component (B), wherein the content of the compound is 15% by mass or more and less than 40% by mass.

27. The fiber-treating agent according to any one of claims 21 to 26, wherein the compound or the liquid film-splitting agent comprises a compound having a siloxane chain in its main chain.

28. The fiber-treating agent according to any one of claims 21 to 26, wherein the compound or the liquid film-splitting agent contains a polyoxyalkylene-modified silicone.

29. The fiber treatment agent according to claim 28, wherein the polyoxyalkylene-modified silicone has a molar number of addition of the polyoxyalkylene group of 3 or more and 10 or less.