Nonwoven fabric, liquid-impregnated sheet, and wiping sheet

Abstract

The present invention proves a non-woven fabric, and a liquid-impregnated sheet and wiping sheet which use the non-woven fabric. The non-woven fabric contains phosphorus-modified polyester-based fibers that have a modified part modified by a phosphorus compound, wherein: the basis weight is not more than 150 g / m2; and the phosphorus-modified polyester-based fibers are tangled with each other by three-dimensional entanglement in at least the thickness direction. The non-woven fabric may further include cellulose-based fibers and / or adhesion core-sheath composite fibers.

Description

Related applications

[0001] This application claims priority to Japanese Patent Application No. 2020-099988, filed in Japan on 9 June 2020, which is incorporated herein by reference as forming part of this application. [Technical Field]

[0002] This invention relates to nonwoven fabrics, liquid-impregnated sheets, and wiping sheets. [Background technology]

[0003] Polyester fibers possess high strength properties and are widely used as clothing fibers. However, the high strength properties of polyester fibers can sometimes lead to unintended problems, such as pilling, when used as fibers. For example, Patent Document 1 (Japanese Patent Publication No. 61-47818) describes a method to suppress pilling in polyester fibers by partially hydrolyzing polyester fibers to which phosphate esters have been introduced, through further hot water treatment, to obtain polyester fibers with excellent anti-pilling properties.

[0004] Furthermore, Patent Document 2 (Japanese Patent Publication No. 2003-155334) discloses a modified polyester resin suitable for copolymerizing phosphorus compounds to obtain a fibrous structure with good flexibility, as well as polyester fibers and polyester nonwoven fabrics using the same, and states that the obtained nonwoven fabric can be suitably used in applications requiring flexibility, such as nonwoven fabrics for interlining. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 61-47818 [Patent Document 2] Japanese Patent Publication No. 2003-155334 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, in Patent Document 1, it is not described to use the fiber as a non-woven fabric. Furthermore, in the fiber whose anti-pilling property is improved by heat treatment, the hydrolyzed part not only causes the generation of lint, but also reduces the strength of the fiber itself, so that the resilience after the non-woven fabric is deformed by compression cannot be expected. In addition, in Patent Document 2, the main focus is on using it as a core non-woven fabric, and since the non-woven fabric is formed by processing with a needle punch or an embossing roll, when the non-woven fabric is compressed, the non-woven fabric has low deformability.

[0007] Therefore, an object of the present invention is to provide a non-woven fabric excellent in cushioning properties in the thickness direction, as well as a liquid-impregnated sheet and a wiping sheet using the same.

[0008] Another object of the present invention is to provide a non-woven fabric excellent in compression change rate and compression recovery rate, particularly a non-woven fabric excellent in compression change rate and compression recovery rate during liquid impregnation, as well as a liquid-impregnated sheet and a wiping sheet using the same.

Means for Solving the Problems

[0009] As a result of intensive studies to achieve the above object, the inventors of the present invention have found that the phosphorus-modified polyester fiber modified with a phosphorus compound has a modified site acting as a bending point in the fiber. And in order to make use of the bending points generated in the fiber, at a specific basis weight, when the phosphorus-modified polyester fiber is fiber-interlocked by three-dimensional entanglement at least in the thickness direction, not only can it sink greatly during compression in the thickness direction of the non-woven fabric, but also the compression recovery is good by utilizing the strength of the polyester fiber. And, surprisingly, it has been found that when using this fiber, the compression change rate and the compression recovery rate, particularly during liquid impregnation, can be improved, and the present invention has been completed.

[0010] That is, the present invention can be configured in the following aspects. 〔Aspect 1〕 It contains phosphorus-modified polyester fibers having modified sites modified by phosphorus compounds, with a basis weight of 150 g / m². 2 The following (preferably 10-130 g / m²) 2 It may be within the range of 20-100 g / m², more preferably 20-100 g / m². 2 ) a nonwoven fabric in which the phosphorus-modified polyester fibers are interwoven in the thickness direction by three-dimensional entanglement. [Aspect 2] A nonwoven fabric according to Embodiment 1, further containing cellulosic fibers, wherein the phosphorus-modified polyester fibers and the cellulosic fibers are interwoven in the thickness direction by three-dimensional entanglement. [Aspect 3] A nonwoven fabric according to embodiment 2, wherein the mass ratio of the cellulose fiber to the phosphorus-modified polyester fiber is (former / latter) = 95 / 5 to 10 / 90 (preferably 95 / 5 to 30 / 70, more preferably 95 / 5 to 50 / 50). [Aspect 4] A nonwoven fabric according to any one of embodiments 1 to 3, further containing fusible core-sheath type fibers, wherein at least the phosphorus-modified polyester fibers and the fusible core-sheath type fibers are inter-fiber entangled in the thickness direction by three-dimensional entanglement. [Aspect 5] A nonwoven fabric according to Embodiment 4, wherein the mass ratio of the adhesive core-sheath type composite fiber to the phosphorus-modified polyester fiber is (former / latter) = 70 / 30 to 5 / 95 (preferably 65 / 35 to 8 / 92, more preferably 60 / 40 to 10 / 90). [Aspect 6] A nonwoven fabric according to any one embodiment of embodiments 1 to 5, wherein the polyester fiber is a ri Nhara A nonwoven fabric having a phosphorus denaturation rate of 0.5 to 5 mol% (preferably 0.6 to 3.0 mol%, more preferably 0.7 to 2.5 mol%) as a percentage of the material. [Aspect 7] A nonwoven fabric according to any one of embodiments 1 to 6, wherein the nonwoven fabric has a spunlace structure. 3 [Aspect 8] A nonwoven fabric according to any one of embodiments 1 to 7, wherein the compression change rate when wet is 18.0% or more (preferably 19.5% or more, more preferably 21.0% or more, and particularly preferably 25.0% or more). [Aspect 9] A nonwoven fabric according to any one of embodiments 1 to 8, wherein the compression recovery rate when wet is 7.0% or more (preferably 8.0% or more, more preferably 11.5% or more). [Aspect 10] A nonwoven fabric according to any one of embodiments 1 to 9, wherein the static friction coefficient between the nonwoven fabric and BioSkin (artificial skin) when dry is 0.060 or less (preferably 0.058 or less, more preferably 0.055 or less). [Aspect 11] A nonwoven fabric according to any one of the embodiments 1 to 10, which is intended for application to the human body. [Aspect 12] A liquid-impregnated sheet made using a nonwoven fabric described in any one of embodiments 1 to 11. [Aspect 13] A wiping sheet made using a nonwoven fabric as described in any one of embodiments 1 to 11.

[0011] Furthermore, any combination of at least two components disclosed in the claims and / or the specification and / or drawings is included in the present invention. In particular, any combination of two or more claims described in the claims is included in the present invention. [Effects of the Invention]

[0012] The present invention provides a nonwoven fabric with excellent cushioning properties in the thickness direction. Furthermore, when this nonwoven fabric is impregnated with a liquid, it exhibits good deformability when compressed in the thickness direction. Moreover, when the load in the thickness direction is reduced, it can regain its thickness and exhibit good recovery properties when liquid impregnated. In addition, the nonwoven fabric of the present invention can also suppress the generation of lint. [Brief explanation of the drawing]

[0013] This invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustrative and explanatory purposes only and should not be used to define the scope of this invention. The scope of this invention is defined by the appended claims. [Figure 1] This is a schematic diagram illustrating a method for measuring compression recovery rate and compression deformation rate. [Figure 2] This is a schematic plan view showing a sample cut from a liquid-impregnated nonwoven fabric, used when measuring the coefficient of static friction between the nonwoven fabric and a bioskin plate. [Figure 3] This is a schematic plan view illustrating the state of the sample used when measuring the static friction coefficient between a liquid-impregnated nonwoven fabric and a bioskin plate. [Figure 4] This is a schematic side view illustrating the test apparatus used to measure the coefficient of static friction between a liquid-impregnated nonwoven fabric and a bioskin plate. [Figure 5] This is a schematic diagram illustrating how a sample is held in the hand during a sensory evaluation. [Modes for carrying out the invention]

[0014] The nonwoven fabric of the present invention is a nonwoven fabric containing phosphorus-modified polyester fibers having modified areas modified by phosphorus compounds, and has a basis weight of 150 g / m². 2 The following describes a nonwoven fabric in which the phosphorus-modified polyester fibers are interwoven by three-dimensional entanglement at least in the thickness direction.

[0015] (Phosphorus-modified polyester fiber) Phosphorus-modified polyester fibers are fibers obtained by melt spinning a modified polyester polymer, in which the main repeating unit is ethylene terephthalate, by adding a phosphorus compound.

[0016] Polyester polymers whose main repeating unit is ethylene terephthalate contain terephthalic acid as the main dicarboxylic acid or its lower alkyl ester derivative as terephthalic acid units, and ethylene glycol as the main glycol or ethylene oxide as ethylene glycol units.

[0017] The polyester polymer may contain structural units derived from other bifunctional compounds as other dicarboxylic acid units and / or diol units, in an amount less than 30 mol%, preferably less than 10 mol%, based on its total constituent units, as long as it does not impede the effects of the present invention.

[0018] Structural units derived from such other bifunctional compounds include aromatic dicarboxylic acids such as isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, biphenyldicarboxylic acid, diphenyl etherdicarboxylic acid, diphenyl sulfonidedicarboxylic acid, and diphenyl ketonedicarboxylic acid; aliphatic dicarboxylic acids such as malonic acid, succinic acid, adipic acid, azelaic acid, and sebacic acid; alicyclic dicarboxylic acids such as decalindicarboxylic acid and cyclohexanedicarboxylic acid; glycolic acid, hydroxyacrylic acid, hydroxypropionic acid, asiatic acid, quinobatic acid, hydroxybenzoic acid, and mandelic acid. a Examples of structural units derived from bifunctional components include hydroxycarboxylic acids such as trolactic acid; aliphatic lactones such as ε-caprolactone; aliphatic diols such as trimethylene glycol, tetramethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, and polyethylene glycol; aromatic diols such as hydroquinone, catechol, naphthalenediol, resorcinol, bisphenol A, and bisphenol S; and alicyclic diols such as cyclohexanedimethanol. These structural units may be used individually or in combination of two or more types.

[0019] The polyester polymer used in this invention is copolymerized with a phosphorus compound, and the copolymerized portion with the phosphorus compound imparts flexibility to the fiber. The phosphorus compound is not particularly limited as long as it can copolymerize with the polyester polymer, and examples include (A) inorganic phosphorus compounds such as red phosphorus, yellow phosphorus, phosphorus trichloride, phosphorus pentachloride, and phosphorus pentoxide; (B) inorganic acids and their salts such as phosphoric acid, phosphorous acid, and polyphosphate; (C) aliphatic or aromatic esters of phosphorous acid (including partial esters); and (D) aliphatic or aromatic esters of phosphoric acid (including partial esters). These phosphorus compounds may be used alone or in combination of two or more. The amount of modification of the phosphorus compound in the polyester polymer is the amount of phosphorus relative to the total acid component in the polyester polymer. Nhara As a percentage of the phosphate, the phosphorus denaturation rate may be, for example, 0.5 to 5 mol%, preferably 0.6 to 3.0 mol%, and more preferably 0.7 to 2.5 mol%.

[0020] Of these phosphorus compounds, dialkyl phosphates represented by the following formula (I) are preferably used.

[0021] [ka]

[0022] (In the formula, R 1 and R 2 (Each of these independently represents a linear or branched alkyl group with 3 to 8 carbon atoms.)

[0023] In formula (I), alkyl group R 1 and R 2The alkyl group may be a branched alkyl group, but a linear alkyl group is preferred. Preferred dialkyl phosphate esters include di-n-propyl phosphate, di-n-butyl phosphate, di-t-butyl phosphate, di-n-pentyl phosphate, di-n-hexyl phosphate, di-n-heptyl phosphate, di-n-octyl phosphate, (n-propyl)(n-butyl) phosphate, (n-propyl)(n-pentyl) phosphate, (n-propyl)(n-hexyl) phosphate, (n-propyl)(n-heptyl) phosphate, (n-propyl)(n-octyl) phosphate, (n-butyl)(n Examples include (n-pentyl)phosphate, (n-butyl)(n-hexyl)phosphate, (n-butyl)(n-heptyl)phosphate, (n-butyl)(n-octyl)phosphate, (n-pentyl)(n-hexyl)phosphate, (n-pentyl)(n-heptyl)phosphate, (n-pentyl)(n-octyl)phosphate, (n-hexyl)(n-heptyl)phosphate, (n-hexyl)(n-octyl)phosphate, (n-heptyl)(n-octyl)phosphate, and (n-heptyl)(n-octyl)phosphate, with di-n-butyl phosphate being preferred.

[0024] After melt-kneading a phosphorus-modified polyester polymer by conventional methods, phosphorus-modified polyester fibers can be obtained using a melt-spinning apparatus. Since no hot water treatment is performed on the obtained phosphorus-modified polyester fibers, the copolymerized portion with phosphorus compounds is not hydrolyzed and exists as a flexible portion within the fiber.

[0025] The fineness of the phosphorus-modified polyester fiber is not particularly limited, but may be, for example, 0.5 to 10.0 dtex, preferably 1.2 to 2.2 dtex, and more preferably 1.5 to 1.9 dtex. The average fiber length of the phosphorus-modified polyester fiber is not particularly limited, but from the viewpoint of manufacturing workability and the mechanical properties of the nonwoven fabric, it may be, for example, 10 to 100 mm, preferably 20 to 80 mm, and more preferably 30 to 60 mm.

[0026] The nonwoven fabric of the present invention may consist of at least phosphorus-modified polyester fibers, but may also contain other fibers. Fibers other than phosphorus-modified polyester fibers may include, for example, cellulose fibers from the viewpoint of improving water retention, and fusible core-sheath type composite fibers from the viewpoint of improving the integrity of the nonwoven fabric.

[0027] For example, the nonwoven fabric of the present invention may be (i) a nonwoven fabric in which phosphorus-modified polyester fibers and cellulose fibers are interwoven by three-dimensional entanglement at least in the thickness direction, (ii) a nonwoven fabric in which phosphorus-modified polyester fibers and fusible core-sheath type composite fibers are interwoven by three-dimensional entanglement at least in the thickness direction, or (iii) a nonwoven fabric in which phosphorus-modified polyester fibers, cellulose fibers and fusible core-sheath type fibers are interwoven by three-dimensional entanglement at least in the thickness direction.

[0028] (Cellulose fiber) Cellulosic fibers include plant fibers such as cotton, hemp, and pulp; regenerated fibers such as rayon and cupro; and refined cellulose fibers such as lyocell (Tencel). These cellulose fibers may be used individually or in combination of two or more. Of these, rayon is preferred due to its availability and ease of handling. Cellulosic fibers may be partially fibrillated, but from the viewpoint of handling, it is desirable that they are not substantially fibrillated.

[0029] The fineness of the cellulose fibers is not particularly limited, but may be, for example, 0.5 to 10.0 dtex, preferably 1.2 to 2.2 dtex, and more preferably 1.5 to 1.9 dtex. The average fiber length of the cellulose fibers is not particularly limited, but from the viewpoint of manufacturing workability and the mechanical properties of the nonwoven fabric, it may be, for example, 10 to 100 mm, preferably 20 to 80 mm, and more preferably 30 to 60 mm.

[0030] The mass ratio (former / latter) of cellulose fibers to phosphorus-modified polyester fibers can be selected from a wide range, for example, 95 / 5 to 10 / 90. In the present invention, the inclusion of phosphorus-modified polyester fibers improves the elasticity when wet, which cannot be obtained with cellulose fibers alone. The mass ratio (former / latter) of cellulose fibers to phosphorus-modified polyester fibers is preferably 95 / 5 to 30 / 70, and more preferably 95 / 5 to 50 / 50.

[0031] (Adhesive core-sheath type composite fiber) Adhesive core-sheath type composite fibers are composed of a resin component that forms the core and a resin component that forms the sheath, with the sheath having adhesive properties. Various resin components can be used for the sheath as long as they can form an adhesive portion, but from the viewpoint of workability, it is preferable that the sheath has heat-sealing properties. Preferred sheath materials include polyolefin resins such as polyethylene, polypropylene, modified polymers, blends, and copolymers thereof, and modified polyester resins other than phosphorus-modified polyesters (for example, modified polyethylene terephthalate modified with isophthalic acid), and preferably polyethylene and modified polymers, blends, copolymers, and modified polyethylene terephthalate. For example, when a heat-sealable resin is used as the sheath, the melting point of the heat-sealable resin may be, for example, 80 to 150°C, and preferably 100 to 140°C.

[0032] On the other hand, the core portion is not particularly limited as long as it can be fibrousized with the sheath portion that forms the adhesive portion, and the sheath portion can maintain its use as a fiber even when the adhesive portion is formed, and a suitable resin component is selected depending on the sheath portion. Preferred core portions include, for example, polyolefin resins such as polypropylene and polyester resins such as polyethylene terephthalate. When a heat-fusible resin is used for the sheath portion, the melting point of the resin component of the core portion may be, for example, 10°C or more, preferably 20°C or more, and more preferably 30°C or more, than the melting point of the resin component of the sheath portion.

[0033] For example, suitable core / sheath combinations include polyethylene terephthalate / polyethylene, polyethylene terephthalate / modified polyethylene terephthalate, polypropylene / polyethylene, and polypropylene / modified polypropylene. Among these, the polypropylene / polyethylene combination is preferred because it is inexpensive and commonly used in nonwoven fabrics.

[0034] From the viewpoint of forming a strong adhesive joint, it is preferable that in the adhesive core-sheath type composite fiber, the low-melting-point component forming the sheath covers at least 40%, and particularly 60%, of the area surrounding the core. Furthermore, the composition ratio of the core to the sheath may be, for example, 90 / 10 to 10 / 90 by mass ratio, preferably 80 / 20 to 20 / 80, and more preferably 70 / 30 to 30 / 70.

[0035] The cross-sectional shape of the fusible core-sheath type composite fiber is not particularly limited and can be any shape, such as a round core-sheath, an eccentric core-sheath, or a core-sheath with an irregular cross-section. The fineness of the fusible core-sheath type composite fiber may be, for example, 0.5 to 10.0 dtex, preferably 1.0 to 5.0 dtex, and more preferably 1.4 to 2.2 dtex, from the viewpoint of improving morphological stability. The average fiber length of the fusible core-sheath type composite fiber is preferably in the range of 10 mm to 80 mm, for example, from the viewpoint of manufacturing workability and the mechanical properties of the nonwoven fabric. More preferably it is 30 mm to 70 mm, and even more preferably 35 mm to 60 mm. By using such short fibers in the fusible core-sheath type composite fiber, it is possible to improve the strength and elongation of the nonwoven fabric while increasing the mobility and degree of entanglement of the fibers through entanglement treatment.

[0036] Furthermore, the mass ratio (former / latter) of the fusible core-sheath type composite fiber and the phosphorus-modified polyester fiber can be appropriately set depending on the presence or absence of cellulose fibers, for example, it may be 70 / 30 to 5 / 95. In particular, since the fusible core-sheath type composite fiber can be combined with the flexible phosphorus-modified polyester fiber to impart good cohesion to the nonwoven fabric, the mass ratio (former / latter) of the fusible core-sheath type composite fiber and the phosphorus-modified polyester fiber may preferably be 65 / 35 to 8 / 92, and more preferably 60 / 40 to 10 / 90.

[0037] The content of the adhesive core-sheath type composite fiber may preferably be 7% by mass or more and 17% by mass or less, and more preferably 8% by mass or more and 15% by mass or less.

[0038] The nonwoven fabric of the present invention may further contain fibers other than phosphorus-modified polyester fibers, cellulose fibers, and fusible core-sheath type composite fibers, as long as they do not impair the effects of the present invention. Examples of such fibers include polyester fibers (excluding phosphorus-modified polyester fibers), polyolefin fibers, polyamide fibers, acrylic fibers, and polyvinyl alcohol fibers. One embodiment of the nonwoven fabric may further contain various additives such as flame retardants, hydrophilic agents, water repellents, colorants (such as pigments), antibacterial agents, antifungal agents, deodorants, oil components, fragrances, and adhesives.

[0039] [Manufacturing method for nonwoven fabrics] Nonwoven fabrics can be obtained by forming a web using the various fibers described above by a dry method, from the viewpoint of ensuring space for fiber mixing and liquid impregnation, and then entangling the fibers in the web by an entanglement treatment. Furthermore, if fusible core-sheath type composite fibers are present, adhesive portions may be formed on the fusible core-sheath type composite fibers by an adhesive treatment as needed.

[0040] Specifically, the phosphorus-modified polyester fibers and other fibers as needed are blended together, and then the fibers are carded using a carding machine to create a web. The web may be a parallel web in which the fibers are arranged in the direction of the carding machine's movement, a cross web in which parallel webs are cross-laid, a random web in which the fibers are arranged randomly, or a semi-random web in which the fibers are arranged to a degree in between. However, considering the high degree of conformability in all directions when the sheet is used, a random web is preferred, and considering the high productivity, a semi-random web is preferred.

[0041] In the entanglement process, at least a portion of the fibers extending in the planar direction become entangled in at least the thickness direction, causing the fibers to intertwine in three dimensions. Mechanical bonding between the fibers then integrates them into a nonwoven fabric. Here, "mechanical bonding" refers to physical entanglement and does not include bonding by adhesive. Therefore, the entanglement treatment is not particularly limited as long as it is a mechanical bonding method used in the bonding method of nonwoven webs, but from the viewpoint of enabling dense entanglement of the fibers, it is preferable to perform water flow entanglement on the obtained web. Water flow entanglement treatment involves, for example, making a columnar stream of water, sprayed at high pressure, collide with the web placed on a porous support member described later, causing the constituent fibers of the web to become densely three-dimensionally entangled and integrated. The nonwoven fabric obtained by water flow entanglement has a spunlace structure.

[0042] When applying three-dimensional entanglement to a web, a preferred method involves placing the web on a movable porous support member and treating it once or multiple times with a water flow at a water pressure of 0.5 to 15 MPa. The nozzle plates are arranged in rows perpendicular to the direction of web movement, ensuring uniform water flow impact on the web. To improve the uniformity of the web thickness, the water pressure is particularly preferably in the range of 1.5 to 12 MPa. Furthermore, the water flow entanglement treatment is preferably performed on both sides of the web at least twice on each side, and a total of five times or more. From the viewpoint of uniform entanglement on the web, the distance between the nozzles and the web is preferably 1 to 10 cm. The water flow may also be sprayed from a nozzle plate with, for example, one or two rows of nozzles with a hole diameter of 0.05 to 0.10 mm and spacing of 0.30 to 1.50 mm.

[0043] The porous support member on which the web is placed can be, for example, a mesh screen or perforated plate made of metal or resin. From the viewpoint of improving the flatness of the nonwoven fabric surface, it is preferable that the water flow entanglement is performed on a woven structure of fine fibers (e.g., a plain weave structure) in at least the final stage of the water flow entanglement treatment.

[0044] Furthermore, in order to improve the surface flatness of the web, it is preferable that the nozzle plate used in the final stage of the water flow entanglement treatment on the porous support member has one to two rows of injection holes with a diameter of 0.05 to 0.10 mm and a spacing of 0.30 to 1.00 mm. The resulting nonwoven fabric can be dried by conventional methods as needed and then used. <Adhesion process> When having core-sheath type composite fibers, a fiber adhesion process may be further performed. In this adhesion process, while maintaining the entangled structure, an adhesion part can be formed between the adhesion core-sheath type composite fibers. The adhesion process can be appropriately selected according to the resin component used in the adhesion part between the adhesion core-sheath type composite fibers. For example, an adhesion part may be formed under a solvent in which only the sheath part of the adhesion core-sheath type composite fiber softens, or a heat-fused core-sheath type composite fiber may be used to melt the sheath part by heat treatment to form an adhesion part. From the perspective of simplicity, the adhesion process by heat treatment is preferred.

[0045] When performing heat treatment, as long as the temperature and the like can be controlled so that an adhesion part is formed for the adhesion core-sheath type composite fiber while no adhesion part is formed for the non-adhesion core-sheath type composite fiber, it is not particularly limited, and various dryers such as a hot air dryer and a cylinder dryer can be used. In the heat treatment process, the amount of heat may be adjusted so that the temperature of the web becomes higher than the melting point of the sheath part of the adhesion core-sheath type composite fiber contained in the web.

[0046] In the case of heat-fused core-sheath type composite fibers, a cooling process may be further performed to fix the adhesion part. The cooling process may be performed by appropriately adjusting the time from after the heat treatment process to winding to release heat from the web, or may be performed using a cooling means. In order to fix the adhesion part and improve the form stability and hairiness prevention of the web, it is preferable to wind after the temperature of the web becomes lower than the melting point temperature of the sheath part of the heat-fused core-sheath type composite fiber.

[0047] [Non-woven fabric] The non-woven fabric of the present invention has a basis weight of 150 g / m 2 or less, and since the phosphorus-modified polyester-based fibers are fiber-interlocked by three-dimensional entanglement at least in the thickness direction, when compressed in the thickness direction of the non-woven fabric, not only can it be greatly deformed, but also the compression recovery rate after being deformed once can be increased.

[0048] (Basis weight) The basis weight of the non-woven fabric is preferably 10 to 130 g / m 2It may be within the range of 20-100 g / m², more preferably 20-100 g / m². 2 It may also be within the range of [specify range]. Furthermore, if it has adhesive core-sheath type composite fibers, the basis weight of the nonwoven fabric is preferably 10 to 80 g / m². 2 It may be within the range of 20-60 g / m², more preferably 20-60 g / m². 2 It may be within the range of [a certain limit].

[0049] (thickness) The thickness of the nonwoven fabric is not particularly limited, but may be in the range of 0.05 to 10 mm, preferably in the range of 0.10 to 8 mm, and more preferably in the range of 0.20 to 5 mm. If the thickness is too thin, it tends to be difficult to maintain the shape of the nonwoven fabric, and if the thickness is too thick, the sheet-like fiber aggregate tends to become too thick, resulting in insufficient entanglement between the fibers.

[0050] (Apparent density) The apparent density of nonwoven fabrics is, for example, 0.04 to 0.20 g / cm³. 3 It may be within the range of 0.06 to 0.15 g / cm³, preferably 0.06 to 0.15 g / cm³. 3 It may be within the range of (g / m²). Here, apparent density is the value obtained by dividing the basis weight of the nonwoven fabric by its thickness. If the apparent density of the nonwoven fabric is too low, the dimensional stability tends to decrease, and if the apparent density of the nonwoven fabric is too high, the liquid retention capacity tends to decrease. The apparent density of the nonwoven fabric constituting the sheet of the present invention is the basis weight (g / m²). 2 ) and thickness (mm) can be used to calculate (the apparent density (g / cm³) of the nonwoven fabric. 3 ) = Basis weight (g / m²) 2 ) / thickness (mm) / 1000). Note that the thickness of the nonwoven fabric is measured according to JIS L 1913 "General Test Methods for Nonwoven Fabrics" 6.2.

[0051] (Compression recovery rate under dry conditions) One embodiment of the nonwoven fabric exhibits excellent recovery after being compressed and deformed in a dry state. Therefore, the compression recovery rate, expressed by the following formula, may be, for example, 3.0% or more, preferably 3.5% or more, and more preferably 4.0% or more. The upper limit of the compression recovery rate is not particularly limited, but may be around 30%. Nonwoven fabrics with a high compression recovery rate have excellent cushioning properties. Compression recovery rate = (CB) / A × 100

[0052] Here, A uses 10 layers of nonwoven fabric at 5 g / cm². 2 This is the thickness measured under a load, and B is the thickness after measuring A, and further adding 40 g / cm³ to the nonwoven fabric. 2 The thickness is measured under a load of 5 g / cm³, and C is the thickness measured after B, and then the nonwoven fabric is again measured again. 2 These are the thicknesses measured under the load. These thicknesses are values ​​measured by the methods described in the examples below.

[0053] Figure 1 is a schematic diagram illustrating the method for measuring the compression recovery rate. As shown in Figure 1, the compression recovery rate is measured by first applying a predetermined load X in the thickness direction to a nonwoven fabric laminate 20 made of 10 layers of nonwoven fabric 10 and measuring the thickness A, then applying an even higher load Y to the nonwoven fabric and measuring the thickness B of the nonwoven fabric laminate 20, and finally returning to the original load X to measure the thickness C of the nonwoven fabric laminate 20. By subtracting the proportion of thickness B to thickness A from the proportion of thickness C to thickness A, it is possible to generalize the extent to which the thickness of the nonwoven fabric recovers after a high load is applied, regardless of the thickness of the nonwoven fabric.

[0054] (Compression change rate under dry conditions) One embodiment of the nonwoven fabric exhibits excellent deformability when compressed under dry conditions. Therefore, the compression change rate of the nonwoven fabric, as expressed by the following formula, may be, for example, 10.0% or more, preferably 15.0% or more, and more preferably 18.0% or more. The upper limit of the compression change rate is not particularly limited, but may be around 60%. Nonwoven fabrics with a high compression change rate exhibit excellent softness in the thickness direction. Compression change rate = (AB) / A × 100 Here, A and B are the same as defined in the compression recovery ratio.

[0055] (Compression recovery rate under wet conditions) One embodiment of the nonwoven fabric not only allows for significant deformation when compressed under wet conditions, but also exhibits excellent recovery after deformation. Therefore, when the nonwoven fabric is saturated with a mixture of distilled water and glycerin, the compression recovery rate, expressed by the following formula, may be, for example, 7.0% or more, preferably 8.0% or more, and more preferably 11.5% or more. The upper limit of the compression recovery rate is not particularly limited, but may be around 30%. Compression recovery rate = (CB) / A × 100

[0056] Here, A, B, and C are the same as those defined in the compression recovery rate under dry conditions.

[0057] If the compression recovery rate under wet conditions is high, the nonwoven fabric will deform significantly under high loads, but when the load decreases again, it can return to its original thickness. Therefore, even after being subjected to high loads while containing liquid, the nonwoven fabric can recover its thickness without losing elasticity, and such a nonwoven fabric can maintain its elasticity even after being compressed and deformed while containing liquid.

[0058] (Compression change rate under wet conditions) One embodiment of the nonwoven fabric exhibits excellent deformability when compressed in a wet state. Therefore, when the nonwoven fabric is saturated with a mixture of distilled water and glycerin, the compression change rate, expressed by the following formula, may be, for example, 18.0% or more, preferably 19.5% or more, more preferably 21.0% or more, and particularly preferably 25.0% or more. The upper limit of the compression change rate is not particularly limited, but may be around 60%. Compression change rate = (AB) / A × 100 Here, A uses 10 layers of nonwoven fabric at 5 g / cm². 2 This is the thickness measured under a load, and B is the thickness after measuring A, and further the nonwoven fabric is 40 g / cm². 2 This is the thickness measured under the load.

[0059] Nonwoven fabrics with a high compression change rate under wet conditions, when compressed with a predetermined force, compress significantly in the thickness direction while containing liquid, allowing for efficient release of the liquid contained within the nonwoven fabric as a result of this change.

[0060] (Static friction coefficient between nonwoven fabric and bioskin) In one embodiment, the nonwoven fabric is preferably smooth when applied to the skin. For example, the static friction coefficient (DRY) between the nonwoven fabric and BioSkin (artificial skin) in a dry state may be 0.060 or less, preferably 0.058 or less, and more preferably 0.055 or less. The lower limit is not particularly limited, but may be around 0.020, for example. The static friction coefficient (DRY) between the nonwoven fabric and BioSkin (artificial skin) is a value measured by the method described in the examples below.

[0061] Furthermore, in one embodiment, it is preferable that the nonwoven fabric has smoothness when applied to the skin even in a wet state. For example, the coefficient of static friction (WET) between the nonwoven fabric and BioSkin (artificial skin) in a wet state may be, for example, 0.045 or less, and preferably 0.043 or less. The lower limit is not particularly limited, but may be, for example, around 0.020. The coefficient of static friction (WET) between the nonwoven fabric and BioSkin (artificial skin) is a value measured by the method described in the examples below, and the nonwoven fabric is used in a state containing 400% by mass of distilled water.

[0062] In one embodiment of the nonwoven fabric, the coefficient of static friction between the nonwoven fabric and the bioskin (artificial skin) is approximately the same when dry and when wet. Therefore, the difference in the coefficient of static friction between dry and wet (DRY-WET) may be, for example, 0.025 or less, preferably 0.018 or less, and more preferably 0.016 or less.

[0063] One embodiment of the nonwoven fabric can be suitably used in applications where softness and cushioning are required, whether in a dry or wet state, and can be suitably used in various applications such as cleaning, cosmetic, medical, household, and industrial uses, depending on the purpose.

[0064] Furthermore, nonwoven fabrics that can reduce skin irritation whether dry or wet can be suitably used for applications applied to the human body, especially applications that come into direct contact with human skin. For this reason, the nonwoven fabric of the present invention can be suitably used, for example, as cosmetic puffs (cotton-like material), beauty sheets such as face mask base materials, clothing sheets for protecting the skin, and top sheets for sanitary materials such as disposable diapers and sanitary napkins.

[0065] [Liquid-impregnated sheet or nonwoven fabric for liquid impregnation] The present invention encompasses liquid-impregnated sheets made using the aforementioned nonwoven fabric, that is, liquid-containing sheets in which a liquid is impregnated into the nonwoven fabric. Liquid-impregnated sheets can be suitably used in cleaning applications, cosmetic applications, medical applications, household applications, industrial applications, and the like. The nonwoven fabric of the present invention may be distributed in a dry state and used as a liquid-impregnated nonwoven fabric (for example, cosmetic sheets such as cosmetic puffs (cotton-like material) and face mask base materials) by impregnating it with liquid when in use.

[0066] The liquids used for these applications can be appropriately selected according to the application and may be solutions, dispersions, emulsions, etc., containing known or conventional active ingredients. The liquid may be an aqueous liquid such as water, aqueous solution, or aqueous emulsion, or an organic solvent or an oily liquid using these as a medium, or a mixture thereof.

[0067] The amount of liquid used for impregnation is not particularly limited as long as the desired effect is obtained, and can be appropriately selected according to the purpose. The amount of liquid impregnation may be, for example, 100 to 1000 parts by mass, preferably 150 to 800 parts by mass, per 100 parts by mass of the nonwoven fabric.

[0068] Depending on the application, various cosmetic ingredients, cleansing ingredients, washing ingredients, disinfecting ingredients, medicinal ingredients, cooling ingredients, insect repellent ingredients, coating agents, paints, and finishing agents (such as varnish) can be used as active ingredients. These active ingredients may be used individually or in combination of two or more.

[0069] Furthermore, known or conventional active ingredients can be used as the active ingredient, and depending on the type and use of the active ingredient, appropriate solvents (water, ethanol, glycerin, propylene glycol, dipropylene glycol, butylene glycol, etc.), auxiliary agents (emulsifiers, chelating agents, pH adjusters, neutralizing agents, thickeners, lubricants, crystallization rate retarders, etc.), and additives (ultraviolet absorbers, powders, antioxidants, preservatives, fragrances, fluorescent whitening agents, antistatic agents, flame retardants, deodorants, plasticizers, colorants, etc.) can be used.

[0070] Beauty ingredients (ingredients that improve the body and appearance) include whitening ingredients, anti-aging (antioxidant, anti-wrinkle, anti-sagging) ingredients, anti-inflammatory (irritation relief, anti-allergic) ingredients, cell-activating (turnover promotion, DNA damage repair) ingredients, moisturizing ingredients, emollient ingredients, astringent ingredients, peeling ingredients, blood circulation promoting ingredients, antioxidant ingredients, and warming ingredients. Preferred beauty ingredients include arbutin, kojic acid, vitamin A, vitamin C, vitamin E, astaxanthin, lucinol, acetylglucosamine, ellagic acid, tranexamic acid, linoleic acid, oxyproline, hydroxyproline, tocopherol and their derivatives, water-soluble polymers, amino acids, peptides such as EGF, sugar alcohols, sugars, mucopolysaccharides, various plant extracts, placenta extract, and capsaicin.

[0071] Cleansing ingredients include nonionic surfactants intended for skin cleansing, alcohols (ethanol, polyhydric alcohols, etc.), glycol ethers, and oils (mineral oils, ester oils, waxes, silicone oils, natural oils, etc.).

[0072] In addition to the above-mentioned cleaning components, cleaning agents may include amphoteric surfactants, cationic surfactants, anionic surfactants, solvents, and alkaline agents.

[0073] Examples of disinfectant components include chlorine-based disinfectants (chlorites such as sodium chlorite, hypochlorites such as sodium hypochlorite, chlorates such as sodium chlorate, perchlorates such as sodium perchlorate, and chlorinated cyanurates such as sodium dichloroisopropylmethylphenol cyanurate), alcohols (ethanol, isopropanol, etc.), amphoteric surfactants, quaternary ammonium salts (benzalkonium chloride, benzethonium chloride, etc.), and chlorhexidine.

[0074] Various medicinal ingredients can be used depending on the application. For example, medicinal ingredients used in poultices include anti-inflammatory agents, antihistamines, steroids, analgesics and anti-inflammatory agents, and local anesthetics.

[0075] Cooling ingredients include alcohols such as ethanol, menthol, peppermint oil, camphor, thymol, spiranthol, and methyl salicylate.

[0076] Insect repellent ingredients include eucalyptus extract, menthol, peppermint oil, and diethyltoluamide.

[0077] For example, a cosmetic face mask contains cosmetic ingredients and a solvent, and may also contain other active ingredients, auxiliary agents, additives, etc., as needed. Cleansing sheets contain cleansing ingredients and may also contain other active ingredients (e.g., cosmetic ingredients), solvents, auxiliaries, additives, etc., as needed. The cleaning wiper contains cleaning components and, if necessary, may also contain other active ingredients (such as coating agents, finishing agents, paints, etc.), solvents, auxiliary agents, and additives. Disinfectant and virus wipes contain disinfectant ingredients and may also contain other active ingredients (such as moisturizing ingredients), solvents, auxiliary agents, and additives as needed. The itch-relieving sheet contains a medicinal ingredient and may also contain other active ingredients (such as cooling ingredients and moisturizing ingredients), solvents, auxiliary agents, and additives as needed. Antiperspirant wipes contain cooling ingredients and may also contain other active ingredients (such as astringent ingredients and moisturizing ingredients), solvents, auxiliary agents, and additives as needed. Insect repellent sheets contain insect repellent ingredients and may also contain other active ingredients (such as moisturizing ingredients), solvents, auxiliary agents, additives, etc., as needed.

[0078] Furthermore, the liquid-impregnated sheet of the present invention exhibits excellent compressive deformation properties in a wet state, and when pressed, seat It can deform to release liquid, and because of its high compression recovery rate, it can maintain a soft feel without collapsing after deformation, even when wet. Therefore, it is useful to use it as a skincare sheet for application to the skin, taking advantage of its cushioning properties and pleasant texture. As a skincare sheet, it may be a sheet for rubbing the skin, or a sheet for non-rubbing applications, where the skin is not rubbed.

[0079] One embodiment of the liquid-impregnated sheet can be used as a non-rubbing sheet, such as a beauty sheet impregnated with cosmetic ingredients (e.g., a beauty mask, nail care sheet, scalp care sheet, body care sheet for the back, chest, abdomen, etc., hygiene sheet, etc.), or a medicinal or therapeutic sheet (e.g., an itch-relieving sheet, a poultice, etc.).

[0080] Furthermore, one embodiment of the liquid-impregnated sheet can be used as a rubbing sheet, such as a makeup removal sheet or cleansing sheet impregnated with a wiping and cleaning ingredient, a body washing sheet (sweat wiping sheet, antiperspirant sheet, hair and scalp wipe, baby wipe, hygiene sheet, etc.), an insect repellent sheet, a cooling sheet, or a medicinal or therapeutic sheet (itch-suppressing sheet, etc.).

[0081] Furthermore, in one embodiment, the liquid-impregnated sheet and the liquid-impregnated nonwoven fabric have a low static friction coefficient against the skin in both dry and wet states. Therefore, even when the liquid content in the sheet or nonwoven fabric decreases, wiping can be continued while suppressing an increase in resistance to the skin. [Examples]

[0082] The present invention will be described in more detail below with reference to examples, but the present invention is not limited in any way by these examples. In the following examples and comparative examples, various physical properties were measured by the methods described below.

[0083] [Balance and apparent density] In accordance with JIS L 1913 "General Nonwoven Fabric Testing Methods" 6.2, basis weight (g / m²) 2 The apparent density (g / cm³) was also measured. 3 The weight was calculated by dividing the base weight by the thickness.

[0084] [Thickness] Based on JIS L 1913, a thickness of 5 g / cm was measured using a thickness measuring instrument for a circular horizontal plate with a diameter of 43.7 mm. 2 The thickness was measured when a load was applied, and this was determined as the thickness of the nonwoven fabric.

[0085] [Compression change rate and compression recovery rate] A nonwoven fabric laminate was prepared by stacking 10 sheets of nonwoven fabric cut to a size of 10 cm square, and this was used as a sample during drying. A thickness measuring device with a diameter of 43.7 mm and a circular horizontal plate was used to measure the thickness of the nonwoven fabric laminate with a load of 5 g / cm². 2After applying a load in the thickness direction and measuring the thickness A (mm / 10 layers) of the nonwoven fabric laminate after 10 seconds, a further high load of 40 g / cm² was applied. 2 The load was applied in the thickness direction, and the thickness B (mm / 10 layers) of the nonwoven fabric laminate was measured after 30 seconds. Then, the original load of 5 g / cm² was applied. 2 The nonwoven fabric laminate was returned to its original state, and the thickness C (mm / 10 sheets) was measured after 30 seconds. From the obtained thicknesses A to C (mm / 10 sheets), the compression change rate and compression recovery rate were calculated using the following formulas. Compression change rate (%) = (AB) / A × 100 Compression recovery rate (%) = (CB) / A × 100

[0086] [Compression change rate and compression recovery rate during decompression] Ten pieces of nonwoven fabric, cut to a size of 10 cm square, were prepared and immersed in a mixture of distilled water (manufactured by Fujifilm Wako Pharmaceutical Co., Ltd., product number 042-16973) and glycerin (manufactured by Ken-ei Pharmaceutical Co., Ltd., Glycerin P "Ken-ei") prepared in a ratio of 5 parts distilled water to 4 parts glycerin (by mass). After 30 minutes, the pieces were removed from the water, and the stacked nonwoven fabric layers were subjected to a load of 5 g / cm using a 43.7 mm diameter circular horizontal plate thickness measuring device. 2 After applying a load in the thickness direction and measuring the thickness A (mm / 10 layers) of the nonwoven fabric laminate after 10 seconds, a further high load of 40 g / cm² was applied. 2 The load was applied in the thickness direction, and the thickness B (mm / 10 layers) of the nonwoven fabric laminate was measured after 30 seconds. Then, the original load of 5 g / cm² was applied. 2 The nonwoven fabric laminate was returned to its original state, and the thickness C (mm / 10 sheets) was measured after 30 seconds. From the obtained thicknesses A to C (mm / 10 sheets), the compression change rate and compression recovery rate were calculated using the following formulas. Compression change rate (%) = (AB) / A × 100 Compression recovery rate (%) = (CB) / A × 100

[0087] [Static friction coefficient between nonwoven fabric and bioskin] Using a precision universal testing machine ("Autograph AGS-D" manufactured by Shimadzu Corporation), the frictional force was measured based on ASTM-D1894.

[0088] First, as shown in Figure 2, a sample 30 was prepared by cutting a piece from the obtained nonwoven fabric measuring 4.0 cm in the machine direction (MD) and 11.0 cm in the width direction (CD). In the sample 30 shown in Figure 2, the 1 cm width from the edge in the width direction was designated as the gripping portion 31a, and the remaining 10 cm width was designated as the contact portion 31b. When measuring the sample while it was wet, the sample was impregnated with distilled water (manufactured by Fujifilm Wako Pharmaceutical Co., Ltd., product number 042-16973) at a concentration of 400% by mass.

[0089] Next, using BioSkin Plate, part number P001-001, manufactured by Viewlux Co., Ltd., as the friction-bearing member, a sample 30 was placed on the friction-bearing member 35 as shown in Figures 3 and 4. The gripping portion 31a of the sample 30 was grasped with a clip 36, and a predetermined load was applied from a weight 38 via an acrylic plate 37. The sample 30 was then pulled in the direction of the arrow.

[0090] Specifically, as shown in Figure 4, in a precision universal testing machine equipped with a load cell 32, the friction-to-be-friction member 35 was placed on a table 39, and the sample 30 was placed on top of the friction-to-be-friction member 35. The sample 30 and the friction-to-be-friction member 35 were each provided with gripping portions 31a and 35c facing in opposite directions, and these gripping portions 31a and 35c were held by clips 36.

[0091] Next, an acrylic plate 37 of the same size was placed on the sample 30 in an area of ​​4.0 cm in the machine direction (MD) x 10.0 cm in the width direction (CD) (ground contact area), and the total weight of the acrylic plate 37 and the weight 38 was 5 g / cm². 2 With the load applied, the polyamide yarn 34 was pulled horizontally via the pulley 33, and the sample 30 was pulled horizontally in the width direction (CD) at a speed of 200 mm / min. The static friction coefficient was calculated from the test force obtained.

[0092] [Tests regarding user experience] (sample) Four sheets cut to a size of 7 cm square were stacked to create a dry sample. To prepare a wet sample, a mixture of distilled water (manufactured by Fujifilm Wako Pharmaceutical Co., Ltd., product number 042-16973) and glycerin (manufactured by Ken-ei Pharmaceutical Co., Ltd., Glycerin P "Ken-ei") was prepared in a ratio of 5 parts distilled water to 4 parts glycerin (by mass). 0.3 cc of this mixture was dropped onto the sample from a height of 2 cm, at a concentration of 450% by mass, to impregnate the entire sheet, thus creating a wet sample.

[0093] (Panel testing) Nine subjects (women in their 20s, 30s, and 40s) held one end of the sample between their index and middle fingers and the other end between their ring and little fingers with their right hand, as shown in Figure 5, so that the width direction (CD) of the sample was perpendicular to their fingers. While lightly pressing with the insides of their middle and ring fingers, they rubbed their cheeks twice horizontally with the wiping portion of the sample [width direction (CD) 3 cm × machine direction (MD) 7 cm] without changing the surface. For each sample, we evaluated three items: softness in the thickness direction, surface irritation, and fuzziness.

[0094] [Dry state / Wet state, Softness in the thickness direction] A sensory evaluation was conducted using the method described above, and the softness in the thickness direction was judged on the following three-point scale: ○: Very soft to the touch and elastic. △: It feels somewhat hard to the touch and has little elasticity. ×: Hard to the touch, lacking elasticity

[0095] [Dry / Wet conditions; Surface irritation] A sensory evaluation was conducted using the method described above, and the level of skin irritation was assessed on the following three-point scale. ○: No sensation △: Slightly irritating ×: Feeling a strong sensation

[0096] [Dry / Wet conditions, Fuzziness] The test was conducted using the method described above, and the results were evaluated in the following three stages based on the following criteria. After the test, the surface was made horizontal, and the number of fibers protruding 3 mm or more from the surface was counted in a 3 cm wide (CD) x 7 cm machine direction (MD) area, corresponding to the wiping area shown in Figure 5, held down with the insides of the middle and ring fingers. 〇: 3 or less △: 4 or more and 6 or less ×: 7 or more

[0097] The three items listed above were evaluated in both dry and wet conditions, and the number of people who received a "○" rating for each item was used as the sensory evaluation result. A: 7 or more people B: 4 or more and 6 or less people C: 3 or less people

[0098] Furthermore, when using a nonwoven fabric that has already been impregnated with liquid or other components, it is preferable to remove the impregnated components according to the procedure below before measuring and evaluating the physical properties described above. Specifically, the nonwoven fabric impregnated with liquid or other components is immersed in a cleaning solution for 2 hours to remove the components that were previously impregnated into the nonwoven fabric. The amount of cleaning solution used is calculated based on the area of ​​the nonwoven fabric (100 cm²). 2 Use 2L per unit. Furthermore, while not particularly limited as long as the impregnating components are removed, for example, a washing solution of ion-exchanged water / neutral detergent = 95 / 5 (volume ratio) may be used. As a neutral detergent, for example, Kao Corporation's Cucute (trademark) is used, and the nonwoven fabric is left to stand in the liquid. Next, it is immersed in the same amount of ion-exchanged water for 2 hours to remove the washing solution, and then the nonwoven fabric is air-dried (conditions: 10°C, 65%RH, 24 hours) so as not to change the shape of the nonwoven fabric as much as possible, and can be used as a measurement sample.

[0099] (Reference example 1) As polyester (P), the di-n-butyl phosphate units are converted to phosphorus atoms. total acidA blend of polyethylene terephthalate chips containing 2.5 mol% of the components and polyethylene terephthalate chips containing 10% by mass of titanium dioxide as polyester (Q) was produced in a polyester (P) / polyester (Q) ratio of 40 / 60. After drying, the blend was melted in a melting device located upstream of the melt spinning apparatus, and then supplied to the melt spinning apparatus. The blend was melt-spun at 280°C from a spinneret with a spinning hole, taken up at 1000 m / min, then stretched 2.5 times at 70°C, mechanical crimping was applied by a conventional method, and the fibers were cut to a length of 51 mm to produce polyester fiber staples with a fiber diameter of 1.7 dtex (dtex is abbreviated as T in the table), a phosphorus modification rate of 0.96 mol%, and a titanium dioxide content of 6.0% by mass.

[0100] (Reference example 2) Ri n change A phosphorus-modified polyester fiber was obtained in the same manner as in Reference Example 1, except that the performance ratio was changed to 2.0 mol%.

[0101] (Reference example 3) A phosphorus-modified polyester fiber was obtained in the same manner as in Reference Example 1, except that the fineness was changed to 3.3 dtex.

[0102] (Example 1) After uniformly blending the phosphorus-modified polyester fibers obtained in Reference Example 1, the basis weight was 50 g / m². 2A semi-random card web was fabricated using a conventional method. This card web was placed on a punching drum support with an opening ratio of 25% and a hole diameter of 0.3 mm, and continuously transported longitudinally at a speed of 50 m / min. Simultaneously, a high-pressure water stream was injected from above to perform entanglement, thereby producing an entangled fiber web (nonwoven fabric). For this entanglement process, two nozzles with orifices of 0.10 mm in diameter were provided along the width direction of the web at a spacing of 0.6 mm (distance between adjacent nozzles was 10 cm). The water pressure of the high-pressure water stream injected from the first row of nozzles was set to 3.0 MPa, and the water pressure of the high-pressure water stream injected from the second row of nozzles was set to 4.0 MPa. Furthermore, the web was placed on a flat support with a finer mesh and continuously transported while a high-pressure water stream was injected to perform entanglement. This entanglement treatment was performed using two nozzles with 0.10 mm orifices spaced 0.6 mm apart along the width of the web, both under high-pressure water flow conditions of 4.0 MPa. The material was then dried at 130°C, resulting in a basis weight of 50.2 g / m². 2 We obtained a spunlace nonwoven fabric.

[0103] (Example 2) Except for using the phosphorus-modified polyester fiber obtained in Reference Example 2, the process is the same as in Example 1, with a basis weight of 51.1 g / m². 2 We obtained a spunlace nonwoven fabric.

[0104] (Example 3) Except for using the phosphorus-modified polyester fiber obtained in Reference Example 3, the process is the same as in Example 1, with a basis weight of 48.8 g / m². 2 We obtained a spunlace nonwoven fabric.

[0105] (Comparative Example 1) After uniformly blending the phosphorus-modified polyester fibers obtained in Reference Example 1, the resulting material has a basis weight of 100 g / m². 2 A semi-random card web was fabricated using a conventional method, and then two of these were stacked together to create a punch density of 90 punches / cm². 2 Needle punching was then performed, resulting in a weight of 197.1 g / m². 2 We obtained a needle-punched nonwoven fabric.

[0106] (Comparative Example 2) The spunlace nonwoven fabric obtained in Example 1 was placed in a conventional dyeing vat with water and heat-treated at 130°C for 60 minutes. After further dewatering, it was dried with hot air at 120°C, resulting in a basis weight of 50.5 g / m². 2 We obtained an anti-pilling treated spunlace nonwoven fabric.

[0107] (Comparative Example 3) After uniformly blending the phosphorus-modified polyester fibers obtained in Reference Example 1, the basis weight was 50 g / m². 2 A semi-random card web was manufactured using a conventional method. A heat embossing roll with a diamond-shaped staggered arrangement and a 20% pressing area was heated to 230°C, a linear pressure of 25 kg / cm was applied, and the heat treatment was performed at a speed of 10 m / min, resulting in a basis weight of 51.3 g / m². 2 An embossed nonwoven fabric was obtained.

[0108] (Comparative Example 4) Using only cotton (manufactured by Marusan Sangyo Co., Ltd., fineness 1.0-2.2 dtex, fiber length 10-30 mm), with a basis weight of 50 g / m 2 Except for preparing a semi-random card web, the process is the same as in Example 1, with a basis weight of 49.8 g / m². 2 We obtained a spunlace nonwoven fabric.

[0109] [Table 1]

[0110] Examples 1-3, using phosphorus-modified polyester fibers, exhibit higher compression change rates and compression recovery rates compared to Comparative Examples 1-3, both in dry and wet conditions. Furthermore, Examples 1-3 also suppress the occurrence of fluffing in both dry and wet conditions. In particular, the nonwoven fabrics of Examples 1-2 suppress skin irritation in both dry and wet conditions.

[0111] On the other hand, in Comparative Example 1, a needle-punched nonwoven fabric with a high basis weight, even when phosphorus-modified polyester fibers were used, the characteristics of the phosphorus-modified polyester fibers could not be effectively utilized due to the high basis weight, resulting in fuzzing, and both the compression change rate and compression recovery rate were poor.

[0112] Furthermore, in Comparative Example 2, where the nonwoven fabric obtained in Example 1 was treated with hot water, the modified areas underwent hydrolysis, causing the fibers to break and resulting in significant fuzzing in both dry and wet conditions. In addition, the cut edges caused skin irritation in both dry and wet conditions. Moreover, the elasticity of the fibers was reduced, preventing the fabric from exhibiting softness in the thickness direction in both dry and wet conditions. Furthermore, both the compression change rate and compression recovery rate in the wet condition were poor.

[0113] Furthermore, in Comparative Example 3, which was integrated using an embossing roller, the fibers were not three-dimensionally entangled. As a result, even when phosphorus-modified polyester fibers were used, the nonwoven fabric as a whole could not exhibit softness in the thickness direction in both dry and wet conditions. Moreover, both the compression change rate and compression recovery rate in wet conditions were poor. Furthermore, the occurrence of fluffing could not be suppressed in both dry and wet conditions.

[0114] Comparative Example 4, which is simply cotton, lacks elasticity and therefore cannot exhibit softness in the thickness direction whether dry or wet. Furthermore, when wet, it causes skin irritation. In addition, the compression change rate when wet is not good, and the compression recovery rate when wet is extremely poor.

[0115] (Example 4) Cellulose fiber (regenerated cellulose fiber, "Hope" manufactured by Omi Kenshi Co., Ltd., fineness 1.7 dtex, fiber length 40 mm) 70 parts by mass ,three example 1After uniformly blending 20 parts by mass of the phosphorus-modified polyester fiber obtained from the above method with 10 parts by mass of adhesive core-sheath type composite fiber (a core-sheath type composite fiber in which the core is made of polypropylene and the sheath is made of polyethylene, manufactured by Ube Eximo Co., Ltd., fineness 1.7 dtex, fiber length 51 mm, core-sheath mass ratio (core 39%, sheath 61%)), the basis weight becomes 40 g / m². 2 A semi-random card web was fabricated using a conventional method. This card web was placed on a punching drum support with an opening ratio of 25% and a hole diameter of 0.3 mm, and continuously transported longitudinally at a speed of 50 m / min. Simultaneously, a high-pressure water stream was injected from above to perform entanglement, thereby producing an entangled fiber web (nonwoven fabric). For this entanglement process, two nozzles with orifices of 0.10 mm in diameter were provided along the width direction of the web at a spacing of 0.6 mm (distance between adjacent nozzles was 10 cm). The water pressure of the high-pressure water stream injected from the first row of nozzles was set to 3.0 MPa, and the water pressure of the high-pressure water stream injected from the second row of nozzles was set to 4.0 MPa. Furthermore, the web was placed on a flat support with a finer mesh and continuously transported while a high-pressure water stream was injected to perform entanglement. This entanglement treatment was performed using two nozzles with 0.10 mm orifices spaced 0.6 mm apart along the width of the web, both under high-pressure water flow conditions of 4.0 MPa. The material was then dried at 130°C, resulting in a basis weight of 39.9 g / m². 2 We obtained a spunlace nonwoven fabric.

[0116] (Example 5) The fiber composition ratio was changed to the one shown in Table 2, resulting in a basis weight of 30g / m². 2 Except for preparing the semi-random card web, the process is the same as in Example 4, with a basis weight of 30.4 g / m². 2 We obtained a spunlace nonwoven fabric.

[0117] (Example 6) The fiber composition ratio was changed to that shown in Table 2, resulting in a basis weight of 100g / m². 2A semi-random card web is prepared, and the pressure of the high-pressure water stream injected from the first row of nozzles is set to 5.0 MPa, the pressure of the high-pressure water stream injected from the second row of nozzles is set to 7.0 MPa, and then it is placed on a flat support having a fine mesh and continuously transported, while the pressure of the injected high-pressure water stream is changed to 7.0 MPa, in the same manner as in Example 4, with a basis weight of 99.2 g / m². 2 We obtained a spunlace nonwoven fabric.

[0118] (Example 7) The fiber composition ratio was changed to the one shown in Table 2, resulting in a basis weight of 50g / m². 2 Except for preparing the semi-random card web, the process is the same as in Example 4, with a basis weight of 50.5 g / m². 2 We obtained a spunlace nonwoven fabric.

[0119] (Comparative Examples 5-9) Instead of phosphorus-modified polyester fibers, polyester fibers (Toray Industries, Inc.'s "Tetron" T-471, fineness 1.6 dtex, fiber length 51 mm) were used, and the surface 2 Spunlace nonwoven fabrics were obtained in the same manner as in Examples 1 and 4-7, except that semi-random card webs were prepared with modified fiber composition ratios and basis weights as shown.

[0120] [Table 2]

[0121] As shown in Table 2, we compare the corresponding Examples 1 and 5, 4 and 6, 5 and 7, 6 and 8, and 7 and 9. In Comparative Examples 5-9, general-purpose PET fibers were used instead of phosphorus-modified polyester fibers. Therefore, regardless of the proportion of PET fibers, the dry nonwoven fabric exhibited strong skin irritation. This strong skin irritation is also reflected in the static friction coefficient of the bioskin / nonwoven fabric. Due to the high strength of the PET fibers, a strong force is required to move the nonwoven fabric relative to the bioskin.

[0122] In particular, in Comparative Examples 6-8, the high proportion of cellulose fibers prevents the nonwoven fabric from exhibiting softness in the thickness direction when wet. Furthermore, in Comparative Example 8, which does not contain fusible core-sheath type composite fibers, a significant amount of pilling occurs both when dry and wet. In Comparative Example 9, the high proportion of PET fibers causes the nonwoven fabric to be irritating to the skin both when dry and wet. Comparative Example 5, being composed solely of PET fibers, exhibits the same skin irritation as Comparative Example 9, both when dry and wet. Furthermore, because it does not contain fusible core-sheath type composite fibers, a significant amount of pilling occurs both when dry and wet.

[0123] On the other hand, in Examples 1 and 4-7, which correspond to these comparative examples, phosphorus-modified polyester fibers are used, so the nonwoven fabric is able to suppress skin irritation in both dry and wet conditions. Furthermore, in Examples 1 and 4-7, even when fusible core-sheath type composite fibers are not included, the occurrence of fluffing in both dry and wet conditions is also suppressed.

[0124] Furthermore, comparing Examples 1 and 4-7 with the corresponding Comparative Examples 5-9, although the only difference between them is the use of phosphorus-modified polyester fibers versus PET fibers, all examples show a significant improvement in compression change rate and compression recovery rate compared to the corresponding comparative examples. This allows for greater deformation while containing liquid, improving liquid release properties. Additionally, due to the high compression recovery rate, the nonwoven fabric retains its elasticity without collapsing even after deformation while containing liquid. [Industrial applicability]

[0125] The nonwoven fabric of the present invention exhibits excellent cushioning properties in the thickness direction, as well as good compression change rate and compression recovery rate when impregnated with liquid. Therefore, it can be suitably used in various applications such as cleaning, cosmetic, medical, household, and industrial uses, depending on the purpose.

[0126] As described above, preferred embodiments of the present invention have been explained, but various additions, modifications, or deletions are possible without departing from the spirit of the present invention, and such are also included within the scope of the present invention. [Explanation of symbols]

[0127] 10 Nonwoven fabric 20 Nonwoven Laminates 30 samples 31a Sample gripping part 31b. Contact area of ​​the sample 32 load cells 33 Pulley 34 Polyamide yarn 35 Frictiond member 36 clips 37 Acrylic sheet 38 weights 39 Tables

Claims

1. This material contains phosphorus-modified polyester fibers and cellulose fibers, which have modified sites where the polyester polymer, whose main repeating unit is ethylene terephthalate and in which repeating units derived from other difunctional compounds account for less than 30 mol% of the total repeating units, is modified with a phosphorus compound, and has a basis weight of 150 g / m². ２ The following is observed: The phosphorus-modified polyester fiber and the cellulosic fiber are inter-fiber entangled in the thickness direction by three-dimensional entanglement. The repeating units derived from the aforementioned other bifunctional compounds are dicarboxylic acid units other than terephthalic acid units and / or diol units other than ethylene glycol units. The phosphorus compound is a dialkyl phosphate ester represented by the following formula (I), 【Chemistry 1】 (In the formula, R1 and R2 each independently represent a linear or branched alkyl group having 3 to 8 carbon atoms.) The phosphorus-modified polyester fiber is a nonwoven fabric in which the phosphorus modification rate is 0.5 to 5 mol%, as the ratio of phosphorus atoms to the total acid component in the polyester polymer forming the phosphorus-modified polyester fiber.

2. A nonwoven fabric according to claim 1, wherein the mass ratio of the cellulose fiber to the phosphorus-modified polyester fiber is (former / latter) = 95 / 5 to 10 / 90.

3. A nonwoven fabric according to claim 1 or 2, further containing fusible core-sheath type composite fibers, wherein at least the phosphorus-modified polyester fibers and the fusible core-sheath type composite fibers are inter-fiber entangled in the thickness direction by three-dimensional entanglement.

4. A nonwoven fabric according to claim 3, wherein the mass ratio of the adhesive core-sheath type composite fiber to the phosphorus-modified polyester fiber is (former / latter) = 70 / 30 to 5 / 95.

5. A nonwoven fabric according to any one of claims 1 to 4, the nonwoven fabric having a spunlace structure.

6. A nonwoven fabric according to any one of claims 1 to 5, wherein the compression change rate when wet is 18.0% or more.

7. A nonwoven fabric according to any one of claims 1 to 6, wherein the compression recovery rate when wet is 7.0% or more.

8. A nonwoven fabric according to any one of claims 1 to 7, wherein the coefficient of static friction between the nonwoven fabric and BioSkin (artificial skin) when dry is 0.060 or less.

9. A nonwoven fabric according to any one of claims 1 to 8, which is intended for application to the human body.

10. A liquid-impregnated sheet made using the nonwoven fabric described in any one of claims 1 to 9.

11. A wiping sheet made using the nonwoven fabric described in any one of claims 1 to 9.

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