JP2016102286A - Nonwoven fabric, manufacturing method thereof, and sheet for absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible nonwoven fabric.SOLUTION: A nonwoven fabric includes splittable composite fibers in an amount of 20 mass% or more, the fibers being bonded to each other with a component of the splittable composite fiber (hereinafter referred to as "component A") to form a bonding part. The splittable fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less. The splittable fiber is non-thermally splittable, causing no detachment between sections when heated at T-5°C for 60 seconds, where T°C represents the melting point of the component A.SELECTED DRAWING: None

Description

  The present disclosure relates to a nonwoven fabric using split composite fibers, a method for producing the same, and a sheet for absorbent articles.

  Various nonwoven fabrics using split-type composite fibers that can be split into a plurality of components by external force have been proposed. The split type composite fiber behaves like a single fiber at the stage of manufacturing the fiber web, and after the fiber web is manufactured, a split process in which physical pressure is applied to split into each component, for example, a high pressure water flow process or a so-called needle punch By being subjected to the treatment, it is divided into a plurality of components to form ultrafine fibers. Nonwoven fabrics containing ultrafine fibers are used as sanitary articles (for example, sanitary products, disposable diapers), wipers, artificial leather base fabrics, etc. by utilizing their soft tactile sensation, denseness, or good wipeability with ultrafine fibers. It is used. A nonwoven fabric obtained by dividing a split-type composite fiber using high-pressure water flow treatment is described in Patent Document 1, for example.

  In addition, as the split type composite fiber, a heat split type composite fiber is proposed in which one of the constituent components is formed of a resin having higher heat shrinkability and can be split by heat treatment. The nonwoven fabric comprised using such a heat | fever partitioning type | mold composite fiber is proposed in patent document 2. FIG. Patent document 2 is disclosing the nonwoven fabric excellent in the tactile sense and the dust collection capability formed by dividing | segmenting a heat | fever splitting type | mold composite fiber by heat processing and a pressurization process.

JP-A-8-260316 JP-A-9-273061

  The present embodiment is made for the purpose of providing a flexible nonwoven fabric by suppressing the division of the split-type conjugate fiber.

In one aspect, the present disclosure includes a non-woven fabric that includes 20% by mass or more of split-type composite fibers, and the fibers are bonded to each other by one component of split-type composite fibers (hereinafter referred to as “component A”). Because
The split type composite fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less,
Splittable conjugate fiber, the melting point of component A is taken as T _A ° C., when heated for 60 seconds at T A _-5 ° C., is of non-thermal splitting may not occur delamination between the sections,
Provide a nonwoven fabric.

In another aspect of the present disclosure, the nonwoven fabric includes 20% by mass or more of split-type composite fibers, and the fibers are bonded to each other by one component of split-type composite fibers (hereinafter referred to as “component A”). Because
The split type composite fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less,
The ultrafine fiber formed by dividing or peeling one of a plurality of sections constituting the split-type conjugate fiber does not continuously exist at a length exceeding 30% of the fiber length of the split-type conjugate fiber. ,
Provide a nonwoven fabric.

In another aspect, the present disclosure provides:
Producing a fiber web containing 20% by mass or more of split-type composite fibers Hot-air processing is performed by applying hot air at a temperature at which the component having the lowest melting point among the components constituting the split-type composite fibers is softened or melted. Including
Without subjecting the fiber web to mechanical entanglement,
Provided is a method for producing a nonwoven fabric, in which hot air processing is performed without applying a linear pressure of 10 kg / cm or more to a fiber web.

  The nonwoven fabric of this embodiment has a soft tactile sensation because the division of the split-type conjugate fiber is suppressed and the components of the small section constituting the split-type conjugate fiber are melted or softened. .

FIG. 1 is a perspective view showing a state in which ultrafine fibers are formed on a part of a split-type composite fiber. FIG. 2 is an electron micrograph of the surface of the nonwoven fabric of Example 1. FIG. 3 is an electron micrograph of the surface of the nonwoven fabric of Example 1. FIG. 4 is an electron micrograph of a cross section of the nonwoven fabric of Example 1. FIG. 5 is an electron micrograph of the surface of the nonwoven fabric of Comparative Example 1. 6 is an electron micrograph of a cross section of the nonwoven fabric of Comparative Example 1. FIG.

(Background to the present embodiment)
Generally, a split type composite fiber is used for producing a fabric such as a nonwoven fabric containing ultrafine fibers by utilizing the property of splitting into a plurality of components by an external force or a heat shrinkage force of a constituent component. However, the present inventors can make use of the structure of the split type composite fiber in which a plurality of small sections are aggregated by not actively splitting the split type composite fiber, and have an unprecedented tactile sensation or characteristic. We thought that a non-woven fabric could be obtained. Therefore, as a split-type composite fiber, a fiber that can be split by external force but does not show heat splitting properties, and heat bonding processing by hot air processing is performed so that the splitting is difficult to occur, and a heat-bonding nonwoven fabric is manufactured. As a result, it has been found that a flexible nonwoven fabric can be obtained. Furthermore, the present inventors have found that a heat-bonded nonwoven fabric produced using a split-type conjugate fiber has higher transparency than a heat-bonded nonwoven fabric produced using a core-sheath type conjugate fiber.
Hereinafter, the nonwoven fabric of this embodiment is demonstrated.

(Split type composite fiber)
The nonwoven fabric of this embodiment contains a split type composite fiber. The split type composite fiber refers to a fiber that can be split into a plurality of components by an external force or a heat shrinkage force of a constituent component. In the nonwoven fabric of this embodiment, since the division | segmentation of a split type composite fiber is suppressed, the split type composite fiber exists in the state which has a splitting ability still.

In the present embodiment, as the split-type conjugate fiber, one having no heat splitting property is preferably used. Specifically, when the melting point of the component constituting the split-type conjugate fiber is the lowest and the melting point of the component that forms an adhesive portion in the nonwoven fabric (hereinafter referred to as “component A”) is T _A ° C., T _A Split-type composite fibers that do not cause separation between sections when heated at −5 ° C. for 60 seconds are preferably used. Delamination between the sections, in the fiber side after heating for 60 seconds at T A _-5 ° C., among the plurality of sections constituting the splittable conjugate fiber, one section peeled or separated to form a microfine fiber It is judged that it has occurred. When the peeling occurs between sections in the splittable conjugate fibers to mechanical force is applied, when heated for 60 seconds at T A _-5 ° C., no peeling between the new section In the present embodiment, the fiber is preferably used as a split type composite fiber having no heat splitting property. When a split-type composite fiber that does not have heat splitting properties is used, splitting of the split-type composite fiber does not proceed when subjected to hot air processing, and the formation of ultra-fine fibers is suppressed, so that many ultra-fine fibers are formed. Compared with the non-woven fabric, it is possible to obtain a non-woven fabric with high transparency (transparency). Moreover, when using the nonwoven fabric containing such a split type composite fiber as a top sheet of an absorbent article or a sheet disposed between the top sheet and the absorber, it is formed by splitting the split type composite fiber. Compared with the nonwoven fabric containing a large amount of ultrafine fibers, the liquid permeation rate is increased, and the surface that comes into contact with the user's skin is less likely to be wetted by the liquid returning from the absorber.

  The split-type conjugate fiber has at least one component divided into two or more components in the fiber cross section, and at least a part of the component is exposed on the fiber surface, and the exposed portion is continuous in the length direction of the fiber. It has a fiber cross-sectional structure that is formed. The split type composite fiber used in the present embodiment is composed of two or more components, and the component (A component) having the lowest melting point among the two or more components plays a role of bonding the fibers together. Preferably, the component A is a thermoplastic resin having a melting point of 140 ° C. or lower, more preferably 136 ° C. or lower. On the other hand, components other than component A are thermoplastic resins having a melting point exceeding 140 ° C. Here, melting | fusing point is melting | fusing point of resin after making it into a fiber, and calculates | requires from the DSC curve measured according to JISK7121 (1987). The melting point of the component A is preferably 10 ° C. or more, more preferably 15 ° C. or more lower than the melting points of the other components.

  The components constituting the split-type composite fiber are not particularly limited, and polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, polylactic acid, polybutylene succinate and copolymers thereof, polypropylene , Polyethylene (including high density polyethylene, low density polyethylene, linear low density polyethylene, etc.), polybutene-1, ethylene-propylene copolymer, ethylene-vinyl alcohol copolymer, ethylene-vinyl acetate copolymer, etc. Selected from polyolefin resins, polyamide resins such as nylon 6, nylon 12 and nylon 66, and the like.

The split-type conjugate fiber is composed of two components, for example, the component A and a resin component (hereinafter referred to as “component B”) having a melting point higher by 10 ° C. than the melting point T _A ° C of the component _A. Good. In that case, the combination of the components constituting the split-type composite fiber is polyethylene terephthalate / polyethylene, polypropylene / polyethylene, etc. (polyethylene is any one of high-density polyethylene, low-density polyethylene, and linear low-density polyethylene) Or a combination thereof). Since polyethylene melts at a relatively low temperature and bonds the fibers satisfactorily, it is preferable to use this as component A. When the polyethylene is a high density polyethylene, its thermal shrinkage compared to other thermoplastic resins polymerized with ethylene as a monomer, such as low density polyethylene, linear low density polyethylene, and ethylene-propylene copolymer. Therefore, the heat splitting property of the split-type composite fiber can be reduced. Therefore, the split type composite fiber containing high-density polyethylene as the component A can be further prevented from peeling between sections without causing large thermal shrinkage of the section containing high-density polyethylene even when subjected to heat treatment for thermal bonding. Therefore, it is preferable. Further, when the component having a high melting point combined with the component A is a polyester resin having a high melting point such as polyethylene terephthalate, when the component A is polyethylene, the temperature difference between the melting point and the polyethylene is large. Even if it performs, it is preferable because it is difficult to bulk. In addition, a polyester resin such as polyethylene terephthalate is preferable because the resin itself has a high elastic modulus, and the split-type composite fiber and the nonwoven fabric including the resin have “koshi”, which makes it easy to increase the bulkiness of the nonwoven fabric.

The fineness of the split type composite fiber is preferably 0.6 dtex or more and 6 dtex or less, more preferably 0.8 dtex or more and 4.8 dtex or less, still more preferably 1.2 dtex or more and 3.5 dtex or less, and most preferably. Is 1.5 dtex or more and 2.5 dtex or less.
Further, the number of sections in the split-type conjugate fiber (that is, the number of divisions into each component in the split-type conjugate fiber) is preferably, for example, 4 or more and 32 or less, and is 4 or more and 20 or less. Is more preferable, and most preferably 6 or more and 16 or less. When the split type composite fiber is composed of two components, component A and component B, the number of sections of each component is preferably 3 or more and 8 or less, and the total number of sections is 6 or more and 16 or less. It is preferable.

  When the number of sections is small, the area and volume per section increase, the area and / or volume of the bonded portion increases, and the non-woven fabric may have a hard feel. Further, in order to reduce the number of sections and to reduce the area and volume per section, it is necessary to reduce the fineness of the split-type conjugate fiber itself. Difficult and may reduce the productivity of the nonwoven fabric. On the other hand, the split composite fiber having a large number of sections has a small area exposed on the fiber surface per section depending on the shape of the fiber cross section. As a result, the area of the adhesion point formed by the component A is also reduced, and the resulting nonwoven fabric may not have sufficient tensile strength, or the surface may become fuzzy. In addition, such a split type composite fiber having a large number of sections needs to be manufactured by using a complicated spinning nozzle and strictly controlling the melt spinning conditions. Therefore, the use of such split-type composite fibers may increase the manufacturing cost of the nonwoven fabric.

  The shape of the section is not particularly limited. For example, the split type composite fiber may be one in which wedge-shaped sections are arranged in a chrysanthemum shape. Alternatively, the split-type composite fiber may be one in which each section is arranged in layers in the fiber cross section. Further, the split-type composite fiber may be a so-called solid split-type composite fiber that does not have a cavity portion continuous in the length direction when the fiber cross section is observed, or one or more cavities continuous in the length direction. It may be a so-called hollow split type composite fiber having a portion. From the viewpoint of suppressing division, solid division type composite fibers are preferably used.

  The volume ratio of the components constituting the split-type conjugate fiber may be determined, for example, so that the section of the A component has a desired area and volume. For example, when a split-type conjugate fiber is composed of two components of component A and component B, the volume ratio is preferably 2: 8 to 8: 2 (component A: component B). When the volume ratio is within the above range, the productivity of the composite fiber tends to be high, and the bonded portion can be satisfactorily formed in the nonwoven fabric. A more preferable volume ratio of A component: B component is 4: 6 to 6: 4.

  The fiber length of the split type composite fiber is 10 mm or more and 100 mm or less. Since the split-type conjugate fiber may be split by the force applied when the fiber is cut, if the fiber length is less than 10 mm, the number of ultrafine fibers formed by splitting the split-type conjugate fiber in the nonwoven fabric increases. For example, the transparency of the nonwoven fabric may be reduced. Further, if the fiber length is less than 10 mm, a bulky fiber web is difficult to obtain, and the fiber web may not be produced by a card method using a parallel card machine or the like. When the fiber length of the split composite fibers exceeds 100 mm, it may be difficult to produce a fiber web using, for example, a card machine. In addition, in non-woven fabrics with a low basis weight, if the fiber length exceeds 100 mm, the number of fibers constituting the non-woven fabric will decrease, so the formation of the non-woven fabric may not be stable, or the required non-woven fabric strength will not be obtained. There is. The fiber length is more preferably 25 mm or more and 100 mm or less, still more preferably 32 mm or more and 70 mm or less, and particularly preferably 38 mm or more and 65 mm or less.

(Other fibers)
The nonwoven fabric of this embodiment may contain fibers other than the split composite fibers. Other fibers are not particularly limited, and include, for example, natural fibers such as cotton, silk and wool, viscose rayon, cupra, and solvent-spun cellulose fibers (for example, lentung lyocell (registered trademark) and tencel (registered trademark)). Recycled fibers, polyolefin fibers, polyester fibers and polyamide fibers, (poly) acrylic single fibers made of acrylonitrile, fibers made of engineering plastics such as polycarbonate, polyacetal, polystyrene, cyclic polyolefin, etc. . Other fibers include not only single fibers made of one kind of thermoplastic resin but also composite fibers made of two or more kinds of thermoplastic resins (for example, concentric or eccentric core sheaths). Type composite fiber, sea-island type composite fiber, side-by-side type composite fiber) can also be used. The other fiber may be a heat-adhesive fiber in which a thermoplastic resin having a melting point equal to or lower than that of the component A is exposed on the fiber surface, and in this case, the other fiber is the split composite fiber A. When the bonded portion by the component is formed by heating (that is, the thermally bonded portion by the A component is formed), the thermally bonded portion is formed in the nonwoven fabric together with the A component.

  The fineness of the other fibers is not particularly limited, and may be the same as or different from the fineness of the split composite fibers. The fiber lengths of the other fibers are not particularly limited, but are preferably 10 mm or more and 100 mm or less in the same manner as the split type composite fibers from the viewpoint of production efficiency.

(Configuration of nonwoven fabric)
The nonwoven fabric of this embodiment is a nonwoven fabric that contains 20% by mass or more of split-type composite fibers, and the fibers are bonded to each other by the component A of the split-type composite fibers to form an adhesive portion. The adhesive part is preferably a thermal adhesive part formed by melting or softening the component A by heating, but the adhesive part may be formed by irradiation with an electron beam or the like, or ultrasonic welding. . The split type composite fiber is as described above, and preferably has no heat splitting property.

  When the proportion of the split-type conjugate fiber in the nonwoven fabric is 20% by mass or more, the effect due to the small area and volume of the bonded portion formed by the component A, that is, a flexible tactile sensation can be sufficiently ensured. When the split composite fiber occupies less than 20% by mass, the number of bonded portions decreases, the strength of the nonwoven fabric decreases, or the number of bonded portions decreases, and the nonwoven fabric surface becomes fuzzy. In some cases, it is necessary to use other adhesive fibers, particularly heat-adhesive fibers, or adhesives to ensure the strength of the nonwoven fabric, and the nonwoven fabric may have a hard feel. The proportion of the split composite fibers is preferably 50% by mass or more, more preferably 80% by mass or more. Or the nonwoven fabric may be comprised only with the split type composite fiber.

  The component A is one component of the split-type composite fiber, and is present in the split-type composite fiber as a section corresponding to the number of splits. Therefore, for example, the adhesive part formed by the A component tends to be smaller in area and volume than the adhesive part formed by the sheath component of the core-sheath composite fiber. The nonwoven fabric has a soft tactile sensation due to the small size of the bonded portion. The bonding portion is formed at the intersection of the fibers and the contact between the fibers.

  In the nonwoven fabric of this embodiment, it is preferable that the division | segmentation of a split type composite fiber is suppressed as much as possible. Therefore, in the nonwoven fabric of this embodiment, it is preferable that the fibers are not entangled by mechanical entanglement processing. The mechanical entanglement process is, for example, a needle punch process and a high-pressure fluid flow process (the fluid is, for example, water, air, or water vapor). Since these treatments promote the division of the split-type composite fibers to generate ultrafine fibers and also promote the entanglement between the ultrafine fibers, the nonwoven fabric subjected to these treatments becomes dense and bulky. May become smaller.

  In addition to the mechanical entanglement treatment, the splitting of the split type composite fiber may be promoted by applying pressure to the fiber or drawing the fiber. Therefore, it is preferable that the non-woven fabric of this embodiment is not subjected to a pressure treatment or a stretching treatment after the fiber web is formed. In addition, the extending | stretching process is a process implemented using a pair of gear roll as it describes in Unexamined-Japanese-Patent No. 2012-67426, for example.

  The non-woven fabric of this embodiment is preferably one in which a heat-bonding portion is formed as a bonding portion by the component A by a hot air processing treatment in which hot air is applied to the fiber web. According to the hot air processing, the pressure applied to the fiber web can be reduced and the fibers can be bonded to each other, so that a nonwoven fabric in which the split of the split-type composite fibers is suppressed can be obtained. Or the adhesion part by A component may be formed by irradiation, such as an electron beam, or ultrasonic welding as above-mentioned.

  In the nonwoven fabric of this embodiment, as a result of the division of the split-type conjugate fiber being suppressed, the ultrafine fiber formed by dividing or peeling one section constituting the split-type conjugate fiber is the split-type conjugate fiber. The fiber length of more than 30% can be provided as a form that does not exist continuously. "Ultrafine fiber formed by dividing or peeling one section constituting a split-type conjugate fiber" means that one section of a plurality of sections constituting a split-type conjugate fiber is separated from the other sections. It refers to the ultrafine fibers formed. The fineness of the ultrafine fiber is determined according to the number of sections, the fineness of the split-type composite fiber, and the density of the resin constituting each section. The fineness of the ultrafine fiber is, for example, 0.05 dtex or more and 2 dtex or less, particularly 0.06 dtex or more and 1 dtex or less, and more particularly 0.10 dtex or more and 0.50 dtex or less.

  Further, such an ultrafine fiber “exists continuously in a length exceeding 30% of the fiber length of the split-type composite fiber” means that the fiber length as the ultrafine fiber is 30 of the fiber length of the split-type composite fiber. It is longer than%. Accordingly, in one split-type composite fiber, even if the ultrafine fiber is present in a length of 20% of the fiber length of the split-type composite fiber in one portion and 20% in the other portion. (Total 40%), it does not exist “continuously” in lengths exceeding 30%. FIG. 1 is a schematic diagram showing a state in which ultrafine fibers are formed on a part of one split composite fiber. In FIG. 1, 10 is a split type composite fiber, 1 is an A component, 2 is a B component, and 4 is an ultrafine fiber formed by dividing one section composed of the B component.

  In the nonwoven fabric of this embodiment, it is preferable that the ultrafine fibers do not exist continuously for a length exceeding 20% of the fiber length of the split-type composite fiber, and do not exist continuously for a length exceeding 10%. Is more preferable.

  When the ultrafine fiber is continuously present in a length exceeding 30% of the fiber length of the split-type composite fiber, the entire nonwoven fabric is composed of one section of ultrafine fiber or two or more sections. There is a tendency that many fine fibers are present. Therefore, fluff is likely to occur in the nonwoven fabric, and the transparency may be lowered. In addition, when there are many ultrafine fibers and fineness fibers as described above, when using a nonwoven fabric as a surface sheet of an absorbent article or a sheet disposed between the surface sheet and the absorbent body, a liquid permeable liquid A speed | rate becomes low and the surface which contact | abuts a user's skin becomes easy to get wet with the liquid which returns from an absorber.

  The nonwoven fabric of this embodiment may contain ultrafine fibers or fineness fibers formed by dividing the split type composite fiber. Alternatively, in the split-type composite fiber, there is a partial separation between the sections (when the nonwoven fabric surface is magnified about 300 times with an electron microscope, it is observed as a crack, streak-like deep cut, or fiber swelling). There may be. They are mainly caused by the forces applied during fiber production or during the production of the fiber web. Although the nonwoven fabric of this embodiment does not allow such generation of ultrafine fibers or separation between sections, it is desirable to suppress such generation as much as possible.

  The nonwoven fabric described above may further be partially formed with a film-like pressure-bonding portion. The film-like crimping part is a part where the fibers adhere to each other with the component A filling the gap between the fibers, and the crimping part has a smaller nonwoven fabric thickness than the non-crimping part. It is a part that. The crimping part is formed by the fibers constituting the nonwoven fabric being expanded by, for example, the action of pressure alone, or the action of pressure with one of heat, electron beam and ultrasonic wave, particularly the action of heat and pressure. . In the film-like crimped part, the film formed by the component A may be partially interrupted, and the gap between the fibers is maintained in the part where the film is interrupted. By forming the crimping portion, the strength of the nonwoven fabric can be improved. The crimping part is preferably a thermocompression bonding part formed by the action of heat and pressure.

  Since the crimping part is generally formed by applying pressure, the splitting of the split-type composite fiber is higher in the part than in the non-crimping part, and more ultrafine fibers and fineness fibers are formed. More peeling occurs. Therefore, the crimping portion is a region that is clearly distinguished from the non-crimping portion due to a decrease in the fiber gap due to the formation of a film and the irregular reflection of light by ultrafine fibers or the like. That is, when forming a partial pressure-bonded portion on the nonwoven fabric of the present embodiment, the non-pressure-bonded portion has high transparency as will be described later, and opacity at the pressure-bonded portion by dividing the split-type composite fiber. For example, compared with the nonwoven fabric which consists of a core-sheath-type composite fiber, the crimping | compression-bonding part which is clearer and easy to visually recognize is given, for example. Therefore, the crimping | compression-bonding part can provide the design effect excellent in the nonwoven fabric by selecting the shape etc. suitably.

  The crimping part is formed by the “pressure treatment” that promotes the splitting of the split-type conjugate fiber described above. In this sense, the nonwoven fabric of the present embodiment in which the crimping part is formed is a split-type composite. It can be said that the process which promotes the division | segmentation of a fiber was given. However, before the crimping portion is formed, if the processing for promoting the splitting of the split-type composite fiber such as the pressure treatment is not performed, the boundary between the crimping portion and the non-crimping portion becomes clearer. It is preferable that the non-compressed part of the nonwoven fabric in which the part is formed is not subjected to a treatment for promoting splitting of the split composite fiber after the fiber web is formed.

The pressure-bonding portion is formed so as to occupy preferably 2% to 50%, more preferably 5% to 40%, and particularly preferably 7% to 30% of the area of the nonwoven fabric. If the proportion of the crimping portion is large, the touch of the nonwoven fabric may be hard. The crimping part may be provided with a geometric figure regularly like a dot or may be provided irregularly. Or you may form a crimping | compression-bonding part as drawings, such as an animal, a character, or a flower. When providing a plurality of pressure-bonding parts regularly, the area of one of the crimping portion, preferably 0.5mm ² ~320mm ^2, more preferably 0.6mm ² ~180mm ^2, particularly preferably 0.7mm ² ~80mm ² It is.

The basis weight of the nonwoven fabric of the present embodiment is not particularly limited, and is appropriately selected according to its use. Basis weight of the nonwoven fabric of the present embodiment, for example, 5g / m ² ~150g / m may be ^2, preferably ^{10g / m 2 ~70g / m 2} , more preferably ^{10g / m 2 ~55g / m 2} , particularly preferably ^{12g / m 2 ~30g / m 2} , most preferably from ^{15g / m 2 ~25g / m 2} . When the basis weight of the nonwoven fabric is within this range, it is easy to obtain a soft tactile sensation. Moreover, in addition to a softness | flexibility, higher transparency can be acquired, so that the fabric weight of a nonwoven fabric is small.

Alternatively, the basis weight of the nonwoven fabric of the present embodiment, for example, 5g / m ² ~60g / m may be ^2, preferably ^{10g / m 2 ~45g / m 2} , more preferably from 10g / m ² ~40g / m ^2, particularly preferably 12 g / m ² to 30 g / m ^2, most preferably from ^{15g / m 2 ~25g / m 2} . If the basis weight of the nonwoven fabric is within this range, a highly transparent nonwoven fabric can be obtained. Moreover, higher transparency can be obtained, so that the fabric weight of a nonwoven fabric is small.

The specific volume of the nonwoven fabric of this embodiment is not specifically limited, It selects suitably according to the use etc. Specific volume of the nonwoven fabric of the present embodiment, for example, be a 10cm ³ / g~100cm ³ / g, preferably 20cm ³ / g~80cm ³ / g, more preferably 30cm ³ / g~70cm ³ / g , particularly preferably 45cm ³ / g~65cm ³ / g. The specific volume can be determined from the basis weight and thickness of the nonwoven fabric, and here, the thickness of the nonwoven fabric is measured with a load of 2.94 cN applied per 1 cm ² of the sample. Higher transparency can be obtained, so that the specific volume of a nonwoven fabric is small. However, the specific volume of the nonwoven fabric may change depending on the pressure applied during storage of the nonwoven fabric.

  When the non-woven fabric of this embodiment includes a split-type conjugate fiber composed of two components of the A component and the B component, the nonwoven fabric includes a core-sheath type conjugate fiber (A: sheath, B: core) composed of the A component and the B component. Also show high transparency. The reason for this is not clear, but there is a possibility that an adhesive portion having a small size and light refraction caused by the composite structure of split-type composite fibers are involved.

The transparency of the nonwoven fabric of the present embodiment is obtained by dividing, for example, the whiteness calculated from the data (Y, x, y) value of the color difference reference value measured using a color difference meter, or the whiteness by the basis weight. Whiteness per unit weight obtained in this way, lightness L ^* measured by a colorimetric color difference meter, or lightness L ^* per unit weight obtained by dividing L ^* by the basis weight. The whiteness and brightness are obtained by the method described later.

Nonwoven fabric of the present embodiment, the basis weight is 10g / m ² ~45g / m ² about, and when not having a crimping portion is preferably whiteness of 10 to 35, more preferably whiteness of 12 to 25 . Or the nonwoven fabric of this embodiment is the state which does not have a crimping | compression-bonding part, The whiteness per unit weight is preferably 0.5-1.35, More preferably, it is 0.7-1.25. Alternatively, the nonwoven fabric of the present embodiment, in a state having no crimp portion, when the basis weight is ^{2 ~45g} / m ² approximately 10 g / m preferably has a brightness of 20 to 55, more preferably 30 to 45. Or the nonwoven fabric of this embodiment is the state which does not have a crimping | compression-bonding part, Preferably the brightness per weight is 1-2.5, More preferably, it is 1.2-2.3.

In the nonwoven fabric of this embodiment, the smaller the basis weight, the higher the transparency of the nonwoven fabric. That is, the basis weight is about 12 g / m ^{2 to} 30 g / m ² , and when the pressure bonding part is not provided, the whiteness is preferably 10 to 27, more preferably 15 to 24. Or the nonwoven fabric of this embodiment is the state which does not have a crimping | compression-bonding part, Preferably the whiteness per unit weight is 0.5-1.3, More preferably, it is 0.8-1.2. Alternatively, the nonwoven fabric of the present embodiment, in a state having no crimp portion, when the basis weight is the 12g / m ² ~30g / m ² about preferably 20 to 46, more preferably lightness of 30 to 44. Or the nonwoven fabric of this embodiment is the state which does not have a crimping | compression-bonding part, Preferably the lightness per unit weight is 1.6-2.3, More preferably, it is 1.8-2.25. The nonwoven fabric of the present embodiment covers, for example, the surface of the film or paper in order to improve the tactile sensation of the film or paper on which a drawing of a character or animal is printed, or to protect the film or paper. May be used. In that case, the nonwoven fabric of this embodiment can give a good tactile sensation to a film or the like, or can provide protection, and can make a drawing visible.

  The softness (drapability) of the nonwoven fabric of the present embodiment can be evaluated by, for example, a value obtained by dividing the total bending resistance measured by using a handle ohmmeter by the basis weight, that is, the bending resistance per basis weight. . The measuring method of the bending resistance measured using the handle ohmmeter is as described later. The total bending resistance per unit weight of the nonwoven fabric of the present embodiment is preferably 0.5 to 2.2, more preferably 0.8 to 2.0, and particularly preferably 1. 0-1.8. Such a non-woven fabric having a softness per unit area is soft and has excellent followability to the bent portion when used against the bent portion.

  The nonwoven fabric of this embodiment can also be obtained as a thing with great lateral flexibility. Specifically, the nonwoven fabric of the present embodiment preferably has a total sum of the bending strengths in the longitudinal direction / a total bending strength in the transverse direction of 2.1 to 3.5, more preferably 2.1 to 3. 0.0, particularly preferably 2.2 to 2.8. If the sum of the longitudinal bending resistance / the bending resistance in the lateral direction is within this range, it is easier to bend along a direction parallel to the longitudinal direction, and it is required to bend in a specific direction. Suitable for use in various applications. Here, the bending resistance in the longitudinal direction refers to the ease of bending the nonwoven fabric in a direction orthogonal to the longitudinal direction, and the bending resistance in the lateral direction is orthogonal to the lateral direction of the nonwoven fabric. Refers to the ease of bending when folded in the direction.

  When the nonwoven fabric of this embodiment is also used in an absorbent article in direct or indirect contact with an absorbent body, a liquid (for example, menstrual blood, urine, feces, or urine) is passed through the absorbent body. It can be absorbed, and the liquid absorbed by the absorber is effectively suppressed from returning to the nonwoven fabric side (wet back). In particular, the nonwoven fabric of this embodiment effectively suppresses the liquid absorbed in the second and subsequent times, particularly the second and third times, from returning to the nonwoven fabric side when the liquid is absorbed into the absorbent body multiple times. it can. Therefore, when using the nonwoven fabric of this embodiment as a surface sheet of an absorbent article or a sheet disposed between the surface sheet and the absorbent body, the surface that contacts the user's skin returns from the absorbent body. It is possible to give the user a comfortable feeling of use by making it difficult to get wet with the coming liquid.

(Nonwoven fabric manufacturing method)
The nonwoven fabric of this embodiment is
Producing a fiber web containing 20% by mass or more of split-type composite fibers Hot-air processing is performed by applying hot air at a temperature at which the component having the lowest melting point among the components constituting the split-type composite fibers is softened or melted. A manufacturing method comprising:
Without subjecting the fiber web to mechanical entanglement,
The hot air processing can be performed by a manufacturing method that is performed without applying a linear pressure of 10 kg / cm or more to the fiber web.

  The fiber web can be produced by a known method. The form of the fiber web may be any of a card web such as a parallel web, a cross web, a semi-random web and a random web, an air lay web, and a wet papermaking web. From the viewpoint of suppressing the splitting of the split-type composite fiber, it is preferably a card web that is difficult to apply an external force during manufacturing.

  The obtained fiber web is subjected to hot air processing so that the heat-bonded portion is formed by the component having the lowest melting point (component A) among the components constituting the split-type composite fiber. According to the hot air processing, the external force applied to the fiber web during the heat treatment can be reduced, so that the splitting of the split-type composite fibers does not easily proceed during the heat treatment. The hot air processing may be performed using a device that blows hot air having a predetermined temperature onto the fiber web, for example, a hot air through heat treatment machine and a hot air blowing heat treatment machine. Alternatively, heat treatment using infrared rays may be performed instead of hot air processing. Infrared heat treatment is also preferably used because an external force is hardly applied to the fiber web.

  In any case, the heat treatment is preferably performed without applying a linear pressure of 10 kg / cm or more to the fiber web. When pressure is applied during the heat treatment, division of the split-type composite fiber is promoted, and a nonwoven fabric having desired flexibility, bulkiness, and transparency may not be obtained. For example, in hot air processing, a mesh or the like may be placed on the fiber web for the purpose of preventing the fiber web from curling or adjusting the shape of the nonwoven fabric after the heat treatment, but the weight is 10 kg / cm or more. A mesh or the like is appropriately selected so that the linear pressure is not applied.

The temperature during the hot-air processing is appropriately selected so that the component A of the split-type composite fiber is softened or melted, thereby forming a heat-bonded part. For example, when the melting point of the A component is T _A ° C., a temperature lower than the melting point of the other constituent components of the split-type conjugate fiber may be selected at a temperature of (T _A ) ° C. or higher. Specifically, when the component A is, for example, high-density polyethylene, hot air having a temperature of 130 ° C. to 150 ° C. may be blown.

  When manufacturing the nonwoven fabric, mechanical entanglement processing is not performed. This is to prevent the splitting of the split-type composite fiber from proceeding due to the force applied during the mechanical entanglement process. The mechanical entanglement process is, for example, a needle punch process and a high-pressure fluid flow process. Therefore, according to this manufacturing method, a nonwoven fabric in which fibers are integrated only by thermal bonding is obtained.

The manufacturing method of the nonwoven fabric of this embodiment may further include forming a thermocompression bonding part partially. The thermocompression bonding part can be formed by, for example, hot roll processing using an embossing roll. For example, the temperature of the embossing roll is set to (T _A −50) ° C. or higher and (T _A +30) ° C. or lower (T _A is the melting point of the A component). You may carry out by applying a linear pressure. The shape of the embossing roll is appropriately selected according to the shape to be formed as the thermocompression bonding part. As described above, since pressure is applied in the thermocompression bonding part, the splitting of the split-type composite fiber proceeds, and the degree of splitting is higher than that in the non-thermocompression bonding part, and thus the non-thermocompression bonding part. Transparency is reduced.

(Use)
The nonwoven fabric of the present embodiment can be used for various applications. For example, an infant paper diaper, an adult paper diaper, a sanitary napkin, a cage absorbing sheet ( Panty liners), surface materials for various hygiene articles such as incontinence pads, sheets disposed between the surface material and the absorbent, and sheets for absorbent articles such as back materials, skin-covering sheets (face masks, sticking) Agent cloth), interpersonal wipers (sweat wiping sheets, makeup removal sheets, etc.), various animal wiping sheets, and the like.

  When the nonwoven fabric of this embodiment is used as a surface material of an absorbent article or a sheet disposed between the surface material and the absorbent body, as described above, the liquid is absorbed particularly when the liquid is absorbed a second time. It is difficult for a return to occur, and a comfortable feeling can be given to the user. Moreover, the back material for sanitary articles using the nonwoven fabric of this embodiment may be a form in which the nonwoven fabric of this embodiment is disposed on the surface of a liquid-impermeable sheet. In that case, since the nonwoven fabric of this embodiment has high transparency, when the design is printed on the liquid-impermeable sheet, this is visually recognized.

Hereinafter, the present embodiment will be described by way of examples.
The following fibers were prepared as fibers used in this example.
[Split type composite fiber 1]
It consists of a combination of polyethylene terephthalate (melting point 255 ° C) / high-density polyethylene (melting point 130 ° C) with a fineness of 2.2 dtex, fiber diameter of 16 µm, and fiber length of 51 mm. The sections of polyethylene terephthalate and high-density polyethylene are alternately chrysanthemum. Split type composite fiber (volume ratio 50:50 (polyethylene terephthalate: high density polyethylene)) (trade name DFS (SH), manufactured by Daiwabo Polytech Co., Ltd.) )

[Core-sheath type composite fiber 1]
Core-sheath type composite fiber (core: polypropylene, sheath: high-density polyethylene, volume) composed of a combination of polypropylene (melting point 167 ° C.) / High-density polyethylene (melting point 130 ° C.) having a fineness of 1.6 dtex, a fiber diameter of 16 μm, and a fiber length of 51 mm Ratio 65:35 (core: sheath)) (trade name NBF (H) manufactured by Daiwabo Polytech Co., Ltd.)
[Core-sheath type composite fiber 2]
An eccentric core-sheath composite comprising a combination of polyethylene terephthalate (melting point 255 ° C.) / High density polyethylene (melting point 130 ° C.) having a fineness of 3.3 dtex, a fiber diameter of 21 μm, and a fiber length of 51 mm, and an eccentricity of the core component of 25%. Fiber (core: polyethylene terephthalate, sheath: high-density polyethylene, volume ratio 64:36 (core: sheath))) (trade name NBF (SH) V manufactured by Daiwabo Polytech Co., Ltd.)
In addition, the eccentricity was calculated | required based on following Formula.

Example 1
A parallel web was produced with a web target weight of 20 g / m ² using only a split type composite fiber 1 to which a primary hydrophilic fiber treating agent was adhered, using a parallel card machine. This fiber web was heat-treated for 15 seconds with a hot-air through heat treatment machine set at a temperature of 135 ° C., and a heat-bonded portion was formed from polyethylene of the split-type composite fiber 1 to obtain a nonwoven fabric. The primary hydrophilic fiber treatment agent refers to a treatment agent that imparts to a fiber the property of greatly reducing the hydrophilicity once contacted with water.

(Example 2)
A parallel web was produced with a web target weight of 50 g / m ² using only a split type composite fiber 1 to which a durable hydrophilic fiber treatment agent was adhered, using a parallel card machine. The fiber web, in the hot air through type heat treatment machine set at a temperature 135 ° C., and heat-treated for 15 seconds, the heat-bonded portion is formed by polyethylene splittable conjugate fiber 1, basis weight 51.3 g / m ^2, thickness 2 A 74 mm non-woven fabric was obtained.

(Example 3)
Using only a split type composite fiber 1 to which a fiber treatment agent having a hydrophilicity lower than that used in Example 2 was attached, a parallel card machine was used to form a parallel web with a web target weight of 50 g / m ^2. Produced. This fiber web was heat-treated for 15 seconds in a hot air through heat treatment machine set at a temperature of 135 ° C., and a heat-bonded portion was formed from polyethylene of the split-type composite fiber 2, with a basis weight of 52.4 g / m ² and a thickness of 2 A non-woven fabric of .86 mm was obtained.

(Example 4-1)
A parallel web was prepared using a split card type composite fiber 1 with 20% by mass and a core-sheath type composite fiber 2 with 80% by mass using a parallel card machine with a web target weight of 50 g / m ² . In this example, both the split-type conjugate fiber 1 and the core-sheath type conjugate fiber 2 were used with a durable hydrophilic fiber treatment agent attached thereto. This fiber web was heat-treated for 15 seconds with a hot-air through-type heat treatment machine set at a temperature of 135 ° C., and a heat-bonded portion was formed from polyethylene of the split-type composite fiber 1 and the core-sheath type composite fiber 2, with a basis weight of 48.7 g. A non-woven fabric having a thickness of / m ² and a thickness of 4.23 mm was obtained.

(Example 4-2)
A parallel web was prepared using a split card type composite fiber 1 with 20% by mass and a core-sheath type composite fiber 2 with 80% by mass using a parallel card machine with a web target weight of 50 g / m ² . In this example, both the split-type conjugate fiber 1 and the core-sheath type conjugate fiber 2 were used with a durable hydrophilic fiber treatment agent attached thereto. This fiber web was heat-treated for 15 seconds in a hot air through heat treatment machine set at a temperature of 135 ° C., and a heat-bonded portion was formed from polyethylene of the split-type composite fiber 1 and the core-sheath type composite fiber 2, with a basis weight of 49.9 g. / M ² , a non-woven fabric having a thickness of 4.43 mm was obtained.

(Comparative Example 1)
Using only the core-sheath type composite fiber 1, a non-woven fabric in which a heat-bonding portion was formed by the sheath portion was manufactured in the same procedure as that adopted in Example 1. The core-sheath type composite fiber 1 was used with a primary hydrophilic fiber treatment agent attached thereto. The obtained nonwoven fabric had a basis weight of 20.3 g / m ² and a thickness of 2.07 mm.

(Comparative Example 2-1)
Using only the core-sheath type composite fiber 2, a non-woven fabric in which a heat-bonding portion was formed by the sheath portion was produced in the same procedure as that adopted in Example 2. The core-sheath type composite fiber 2 was used with a durable hydrophilic fiber treatment agent attached thereto. The obtained nonwoven fabric had a basis weight of 44.1 g / m ² and a thickness of 4.24 mm.

(Comparative Example 2-2)
Using only the core-sheath type composite fiber 2, a non-woven fabric in which a heat-bonding portion was formed by the sheath portion was produced in the same procedure as that adopted in Example 2. The core-sheath type composite fiber 2 was used with a durable hydrophilic fiber treatment agent attached thereto. The nonwoven fabric obtained had a basis weight of 48.1 g / m ² and a thickness of 4.82 mm.

[Weight, thickness, specific volume, flexibility]
The basis weight, thickness (non-thermocompression bonding portion thickness), and specific volume of Example 1 and Comparative Example 1 are shown in Table 1, and the basis weight and thickness (non-thermal) of Example 4-1 and Comparative Example 2-1. Table 2 shows the thickness of the crimping part) and the specific volume. Further, the results of evaluating the flexibility of Example 1 and Comparative Example 1 are shown together in Table 1, and the results of evaluating the flexibility of Example 4-1 and Comparative Example 2-1 are also shown in Table 2.
The thickness of the nonwoven fabric was measured using a thickness measuring device (trade name: THICKNESS GAUGE model CR-60A, manufactured by Daiei Kagaku Seisakusho Co., Ltd.) with a load of 2.94 cN applied per 1 cm ^{2 of} the sample.

The drape (flexibility) of the nonwoven fabric was measured according to JIS L 1096 6.19.5 E method (handle ohmmeter method). Specifically, it measured by the following procedure.
A test piece of 20 cm in length and 20 cm in width is placed on a sample stage so that the measurement direction of the test piece is perpendicular to the slot (gap width 10 mm).
Next, when the penetrator blade adjusted so as to be lowered to 8 mm from the surface of the sample stage is lowered and the test piece is pushed in, it is 6.7 cm (one third of the width of the test piece) from either side. At the position, the resistance value against indentation is read at different positions in the vertical and horizontal directions. The maximum value (g) indicated by the microammeter is read as the resistance value.
The measurement is performed in the direction parallel to the MD direction (also referred to as machine direction and longitudinal direction) and the CD direction (also referred to as width direction and lateral direction) of the nonwoven fabric, and the bending resistance is determined at two different locations in the direction parallel to the CD direction. And then measured at two different locations in the direction parallel to the MD direction.
The measurement is performed three times at each measurement location, and the average value is defined as the bending resistance of each measurement location (MD-1, MD-2, CD-1, CD-2), and the total sum and total sum are divided by the basis weight. The value obtained by dividing the sum of the bending stiffness in the MD direction by the sum of the bending stiffness in the MD direction is evaluated as the drape. In the table, MD-1 and MD-2 are values measured by placing the sample on the sample stage so that the longitudinal direction of the sample is orthogonal to the length direction of the slot, and CD-1 and CD-2 are the values of the sample This is a value measured by placing the sample on the sample stage so that the horizontal direction is perpendicular to the length direction of the slot.

[Whiteness, brightness]
The whiteness and the whiteness per unit weight of Example 1 and Comparative Example 1, and the lightness and the lightness per unit weight were evaluated. The evaluation results are shown in Table 3. Whiteness and brightness were evaluated by the following methods.
(Whiteness)
A sample whose basis weight was measured in advance was cut into 30 cm (MD direction) × 21 cm (CD direction) and placed on a black cloth. In this state, the data (Y, x, y) value (Y: reflectance, xy: chromaticity) of the color difference reference value was measured using a color difference meter (CR-310 manufactured by Minolta Camera Co., Ltd.). . The color difference meter used displayed data values when three points were measured. For each sample, the data value is displayed twice (data value is measured twice), the whiteness is calculated from each data value by the following formula, and the average value is calculated as the whiteness of the sample. did. Further, the whiteness was divided by the basis weight to obtain the whiteness per basis weight.

(Lightness L ^* )
A sample whose basis weight was measured in advance was cut into 30 cm (MD direction) × 21 cm (CD direction), placed on a sample stage, and covered with a black cap used for zero point configuration. L ^* , a ^* , and b ^* were measured with the cap on. The measurement was performed 4 times in total by rotating the direction of the sample 90 degrees three times, and the average value was displayed as the measurement result.

  Although Example 1 and Comparative Example 1 are composed of fibers having the same fiber diameter, Example 1 showed lower whiteness and lightness than those of Comparative Example 1, and exhibited high transparency. .

The nonwoven fabrics obtained in Example 1 and Comparative Example 1 were each subjected to hot roll processing using an embossing roll to form a thermocompression bonding part. At the time of hot roll processing, an embossing roll provided with a cylindrical convex part (embossed area of the convex part: 0.79 mm ² ) having a diameter of 1 mm and a height of 0.5 mm is used, the temperature is 100 ° C., the linear pressure is 20 kg / cm. In the nonwoven fabric, the thermocompression bonding portion occupied 19.7% of the total area of the nonwoven fabric.

  Electron micrographs of the surface or cross section of Example 1 and Comparative Example 1 are shown in FIGS. 2 and 3 (Example 1) and FIG. 5 (Comparative Example 1) are photographs of the surface of the non-thermocompression bonded portion of the nonwoven fabric surface at a magnification of 300 times. Furthermore, the electron micrograph which image | photographed the cross section of the thermocompression bonding part of Example 1 and Comparative Example 1 by 500 times magnification is shown in FIG. 4 (Example 1) and FIG. 6 (Comparative Example 1).

  In both Example 1 and Comparative Example 1, a film was formed of molten polyethylene at the thermocompression bonding part. In Example 1, since the splitting of the split-type composite fiber was promoted at the thermocompression bonding part, it was confirmed that ultrafine fibers were formed (FIG. 4). Moreover, in the non-thermocompression bonding part of Example 1, although formation of a peeling part (crack) and ultrafine fiber was observed due to division of the split-type composite fiber in some fibers, the ultrafine fiber had a fiber length. It did not exist continuously exceeding 30%, and the division was suppressed as a whole (FIGS. 2 and 3). Moreover, in Example 1, compared with the comparative example 1, the outline of the thermocompression bonding part was clearer, and the shape of the thermocompression bonding part was visually recognized more clearly.

[Liquid return]
The liquid return properties of Examples 2, 3, 4-2 and Comparative Example 2-2 were evaluated. The evaluation results are shown in Table 4. The liquid return property was evaluated by the following method.
(Liquid return)
(1) In order to measure the liquid return amount, the following articles were prepared.
Absorber (disassembled and taken out of commercially available baby paper diapers)
Plate with injection cylinder (2.5cm inside diameter at the bottom of the cylinder)
0.9% saline (colored with blue dye)
Filter paper (ADVANTEC (registered trademark) No. 2 manufactured by Toyo Filter Paper Co., Ltd.) 10cm x 10cm
Weight (5kg) 10cm x 10cm
(2) Method The liquid return amount was measured according to the following procedure.
(I) A non-woven fabric sample (vertical 42 cm × width 21 cm) is placed on the absorber, and a plate with an injection cylinder is placed thereon.
(Ii) Inject 50 ml of physiological saline warmed to about 37 ° C. from the cylinder. At this time, the physiological saline is left until it cannot be seen from the surface of the nonwoven fabric (the physiological saline is not confirmed as a liquid).
(Iii) Remove the plate with the injection tube and leave it for 10 minutes.
(Iv) After 10 minutes, place filter paper (30 sheets) on the nonwoven fabric and place a 5 kg weight for 20 seconds. Thereafter, the mass of the filter paper is measured (the difference in mass between the filter paper before being placed on the non-woven fabric and the filter paper after placing the weight on the non-woven fabric corresponds to the reverse amount).
(Vi) Return to (i) above and perform the second measurement.
With respect to the liquid return property, three samples were prepared for one sample (nonwoven fabric), and the average value of the liquid return amount measured for each of the three samples was defined as the liquid return amount of the sample.

  In Examples 2, 3, and 4-2, the liquid return amount at the second and third times was smaller than that at Comparative Example 2-2. Moreover, about Example 2 and Example 4-2, the amount of liquid return of the 2nd time was small compared with that of the 1st time, and about Example 3, the change of the liquid return amount of the 1st time and the 2nd time was small. In contrast, in Comparative Example 2-2, the second liquid return amount was larger than the first time, and the third liquid return amount was the largest among the four samples.

  Since the nonwoven fabric of this embodiment is flexible and does not easily cause liquid return, it is suitably used, for example, as a constituent member of absorbent articles.

Claims (10)

A non-woven fabric comprising 20% by mass or more of split-type conjugate fibers, the fibers being bonded to each other by one component of the split-type conjugate fibers (hereinafter referred to as “component A”), and forming an adhesive portion,
The split type composite fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less,
Splittable conjugate fiber, the melting point of component A is taken as T _A ° C., when heated for 60 seconds at T A _-5 ° C., is of non-thermal splitting may not occur delamination between the sections,
Non-woven fabric. It contains 20% by mass or more of split-type conjugate fibers, and the fibers are bonded to each other by one component of split-type conjugate fibers (hereinafter referred to as “component A”) to form an adhesive portion, and a film-like crimped portion is partially A non-woven fabric,
The split type composite fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less,
Splittable conjugate fiber, the melting point of component A is taken as T _A ° C., when heated for 60 seconds at T A _-5 ° C., are of non-thermal splitting may not occur delamination between the sections,
The degree of division of the split-type conjugate fiber in the crimping part is greater than the degree of splitting of the split-type conjugate fiber in parts other than the crimping part,
Non-woven fabric. A non-woven fabric comprising 20% by mass or more of split-type conjugate fibers, the fibers being bonded to each other by one component of the split-type conjugate fibers (hereinafter referred to as “component A”), and forming an adhesive portion,
The split type composite fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less,
The ultrafine fiber formed by dividing or peeling one of a plurality of sections constituting the split-type conjugate fiber does not continuously exist at a length exceeding 30% of the fiber length of the split-type conjugate fiber. ,
Non-woven fabric. It contains 20% by mass or more of split-type conjugate fibers, and the fibers are bonded to each other by one component of split-type conjugate fibers (hereinafter referred to as “component A”) to form an adhesive portion, and a film-like crimped portion is partially A non-woven fabric,
The split type composite fiber is a short fiber having a fiber length of 10 mm or more and 100 mm or less,
The degree of division of the split-type conjugate fiber in the crimping part is greater than the degree of splitting of the split-type conjugate fiber in parts other than the crimping part,
In a portion other than the crimping portion, the ultrafine fiber formed by dividing or peeling one section out of a plurality of sections constituting the split-type conjugate fiber has a length exceeding 30% of the fiber length of the split-type conjugate fiber. In, it does not exist continuously,
Non-woven fabric.   The nonwoven fabric according to any one of claims 1 to 4, wherein Component A is high-density polyethylene. The nonwoven fabric according to any one of claims 1 to 5, wherein the basis weight is 10 g / m ² or more and 55 g / m ² or less.
Non-woven fabric. Producing a fiber web containing 20% by mass or more of split-type composite fibers Hot-air processing is performed by applying hot air at a temperature at which the component having the lowest melting point among the components constituting the split-type composite fibers is softened or melted. Including
Without subjecting the fiber web to mechanical entanglement,
A method for producing a nonwoven fabric, wherein the hot air processing is performed without applying a linear pressure of 10 kg / cm or more to the fiber web.   The manufacturing method according to claim 7, further comprising partially forming the thermocompression bonding portion.   The sheet | seat for absorbent articles containing the nonwoven fabric of any one of Claims 1-6.   The sheet | seat for absorbent articles of Claim 9 which is a sheet | seat arrange | positioned between a surface material or the said surface material, and an absorber.