TWI834962B - Surface material of sanitary material and manufacturing method thereof - Google Patents

Abstract

The present invention provides a method of manufacturing a surface material for sanitary materials that improves abrasion resistance without reducing the skin feel of a surface in contact with the skin. The manufacturing method of the surface material of the hygienic material includes the following steps. The step of preparing a first fiber web including cotton fibers; the step of preparing a nonwoven fabric including long fibers; the step of preparing a second fiber web including cotton fibers and heat fusible short fibers; combining the first fiber web, the long fiber nonwoven fabric and the third The steps of laminating two fiber webs to obtain a first laminated body; applying a high-pressure water flow to the first laminated body to obtain fiber velvet; heating the fiber velvet to soften or melt the surface of the heat-fusible short fibers, thereby making each The process of merging fibers with each other. In the obtained surface material, the surface on the first fiber web side becomes the surface in contact with the skin.

Description

Surface material of sanitary material and manufacturing method thereof

The present invention relates to a surface material used for parts of sanitary materials such as sanitary napkins and disposable diapers that come into contact with the skin, and a manufacturing method thereof. In particular, it relates to a sanitary material that has good skin touch and excellent wear resistance. Surface material and method of manufacturing same.

Conventionally, short fiber nonwoven fabrics or long fiber nonwoven fabrics have been used as surface materials for sanitary materials. Short fiber nonwoven fabrics have excellent skin feel, but have the disadvantage of low breaking strength. On the other hand, although long-fiber nonwoven fabrics have high breaking strength, they have the disadvantage of poor skin feel. Therefore, Patent Document 1 discloses a surface material of a hygienic material in which a long fiber nonwoven fabric and a specific short fiber nonwoven fabric are joined together. Furthermore, as a specific short fiber nonwoven fabric arranged on the skin side, one in which heat-fusible composite short fibers of at least two thermoplastic resin components having a high melting point and a low melting point are fused with each other using a low melting point component is used (Patent Document 1. Request item 1). In addition, as long fiber nonwoven fabrics, those obtained by fusing heat-fusible composite long fibers with at least two thermoplastic resin components of high melting point and low melting point to each other using a low melting point component are used (Patent Document 1, Claim 3).

However, short fiber nonwoven fabrics containing short fibers containing thermoplastic resin components have a poor skin feel compared to short fiber nonwoven fabrics containing natural fibers such as cotton fibers or silk fibers, and may also cause rashes on the skin. Therefore, as a short-fiber nonwoven fabric, a surface material has been proposed that uses a nonwoven fabric containing cotton fibers and integrates long fibers and cotton fibers in the long-fiber nonwoven fabric by entangling them (Patent Document 2, Claim 1). [Prior Art Document] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 9-117470 [Patent Document 2] Utility Model Registration No. 3218416

[Problem to be solved by the invention]

The present invention is an improved invention of the design described in Patent Document 2, and its subject is to improve the wear resistance without reducing the skin feel of the surface of the surface material that comes into contact with the skin. [Means to solve the problem]

Means for solving the above problems include the following aspects. <1> A method of manufacturing a surface material for hygienic materials, characterized by: a first fiber web containing cotton fibers, a nonwoven fabric containing long fibers containing a propylene polymer, and a first fiber web containing cotton fibers and heat-fusible short fibers. After applying high-pressure water flow to the first laminate in which the second fiber webs are sequentially laminated to interweave the cotton fibers, the heat-fusible short fibers, and the long fibers to obtain fiber velvet, the fiber velvet is subjected to Heating softens or melts the surface of the thermally fusible short fibers, thereby using the thermally fusible short fibers to combine the cotton fibers and the long fibers with each other, wherein the first fiber web side and Skin contact.

<2> A method of manufacturing a surface material for hygienic materials, characterized by: a first fiber web including cotton fibers, a second fiber web including cotton fibers and heat-fusible short fibers, and a fiber web containing a propylene-based polymer. After applying high-pressure water flow to a second laminate in which long-fiber nonwoven fabrics are sequentially laminated to interweave the cotton fibers, the heat-fusible short fibers, and the long fibers to obtain fiber velvet, the fiber velvet is subjected to Heating softens or melts the surface of the thermally fusible short fibers, thereby using the thermally fusible short fibers to combine the cotton fibers and the long fibers with each other, wherein the first fiber web side and Skin contact.

＜3＞ A surface material for sanitary materials, consisting of a first fiber web region including cotton fibers, a nonwoven fabric region including long fibers containing a propylene-based polymer, and a second fiber web region including cotton fibers and heat-fusible short fibers. The cotton fibers in the first fiber web area, the long fibers in the non-woven fabric area, and the cotton fibers and thermal fusible short fibers in the second fiber web area are intertwined, and The cotton fiber and the long fiber are fused by the heat-fusible short fiber, and the thickness of the surface material of the sanitary material is 0.50 mm or less, and the first fiber web area is in contact with the skin. [Effects of the invention]

According to the present invention, the wear resistance can be improved without reducing the skin feel of the surface of the surface material that comes into contact with the skin.

In the present invention, the numerical range represented by "～" means a range including the numerical values described before and after "～" as the lower limit and the upper limit.

Within the numerical ranges described in stages in the present invention, the upper limit or lower limit described in a certain numerical range may be replaced by the upper limit or lower limit of other numerical ranges described in stages. In addition, within the numerical range described in this disclosure, the upper limit value or the lower limit value described in a certain numerical range may be replaced with the value shown in the embodiment.

The present invention solves the above problems by using two kinds of cotton fiber webs and adopting a specific manufacturing method. That is, the present invention relates to a method for manufacturing a surface material for hygienic materials, which is characterized in that: a first fiber web including cotton fibers, a nonwoven fabric including long fibers containing a propylene polymer, and a first fiber web including cotton fibers and thermally fused After applying high-pressure water flow to the first laminate in which the second fiber webs of the thermally fusible short fibers are sequentially laminated to intertwine the cotton fibers, the heat-fusible short fibers and the long fibers to obtain fiber velvet, the The fiber velvet is heated to soften or melt the surface of the thermally fusible short fibers, thereby using the thermally fusible short fibers to combine the cotton fibers and the long fibers with each other, wherein the first The fiber mesh side is in contact with the skin. In addition, it relates to a method for manufacturing a surface material of a hygienic material. In the manufacturing method, a first fiber web including cotton fibers and a heat-fusible short fiber is used instead of the first laminated body. A second fiber web and a second laminate in which nonwoven fabrics containing long fibers containing a propylene polymer are laminated in sequence, wherein the side of the first fiber web is in contact with the skin.

The first fiber web used in the present invention essentially contains only cotton fibers, but as long as it is a small amount, hydrophilic fibers such as juan fibers and rayon fibers may be mixed. The first fiber web can be obtained by spreading and aggregating cotton fibers using a known carding method. The unit area weight of the first fiber web is about 10 g/m ² to 20 g/m ² . As the cotton fiber, any conventionally known cotton fiber can be used, and organic cotton, bleached cotton or non-degreased bleached cotton is particularly preferred. Non-degreased bleached cotton has grease components (cotton wax, cottonseed oil, etc. attached to the surface of raw cotton) remaining on the surface of the cotton fiber, so body fluids cannot easily spread toward the surface of the surface material. Therefore, it is less likely to cause stickiness to the skin when used, so it is better. Furthermore, bleached cotton is bleached white and gives a clean feeling to the sanitary material, so it is preferable.

The second fiber web used in the present invention includes cotton fibers and heat-fusible short fibers. As the cotton fiber, it is preferable to use the various types of cotton mentioned above. As the heat-fusible short fibers, those formed of a thermoplastic resin having a melting point are used. For example, polypropylene fiber, polyester fiber or polyamide fiber is used. In the present invention, it is preferable to use a concentric core-sheath type composite short fiber and a thermally fusible short fiber in which the melting point of the sheath component is lower than the melting point of the core component. By softening or melting only the sheath component of the core-sheath type composite short fiber, the fibers are fused and bonded to each other. In order to prevent the composite short fiber from shrinking easily when only the sheath component is softened or melted, it is preferably a concentric core-sheath type. When the heat-fusible short fibers shrink, the obtained surface material is prone to wrinkles and the like. Specifically, a concentric core-sheath type composite short fiber in which the core component is polypropylene and the sheath component is polyethylene, or a concentric core-sheath type composite staple fiber in which the core component is polyethylene terephthalate and the sheath component is polyethylene is used. Short fibers. The fineness and fiber length of the heat-fusible staple fiber are arbitrary. Generally speaking, the fineness is about 1 decitex to 5 decitex and the fiber length is about 10 mm to 100 mm.

The mixing ratio of cotton fibers and heat-fusible short fibers in the second fiber web is preferably cotton fiber: heat-fusible short fiber = 80:20~20:80 (mass ratio), more preferably 70:30~30: 70 (mass ratio), the best is 60:40~40:60 (mass ratio). When the mixing ratio of the heat-fusible short fibers is small, there are fewer fusion bonding points between the fibers, and the wear resistance of the surface material tends to decrease. In addition, when the mixing ratio of the heat-fusible short fibers is large, the fusion bonding between the fibers becomes too strong, and the skin feel of the surface material tends to decrease. Furthermore, the second fiber web can also be obtained by a known carding method, and its unit area weight is also about 10g/m ² to 20g/m ² .

The nonwoven fabric used in the present invention is a long fiber nonwoven fabric containing long fibers containing a propylene-based polymer. The non-woven fabric is used as a surface material for sanitary materials to improve strength, especially tensile strength. The content rate of the long fibers in the long-fiber nonwoven fabric is based on the number of fibers, and is preferably 50 mass% or more, more preferably 90 mass% or more, and still more preferably 99 mass% or more. As the propylene-based polymer, a propylene homopolymer, a propylene·α-olefin random copolymer, a propylene·α-olefin block copolymer, etc. can be used. Here, as α-olefins, α-olefins other than propylene such as ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and 4-methyl-1-pentene can be used. Furthermore, when α-olefin is copolymerized, the copolymerization amount is preferably 1 to 10 mol%. The long fiber may contain one type of these polymers alone, or may contain two or more types. In addition, the propylene-based polymer means a polymer containing 50 mass % or more of a structural unit derived from propylene.

The melt flow rate (MFR (melt flow rate), American Society of Testing Materials (ASTM) D1238, 230°C, load 2160g) of the propylene-based polymer is not particularly limited as long as melt spinning is possible. For example, the MFR can be 1 g/10 minutes to 1000 g/10 minutes, preferably 5 g/10 minutes to 500 g/10 minutes, and more preferably 10 g/10 minutes to 100 g/10 minutes. When the MFR of the propylene-based polymer is within the above range, the strength tends to be improved, which is preferable.

From the viewpoint of spinnability, the content of the propylene-based polymer in the long fibers is preferably 90% by mass or more, more preferably 95% by mass to 100% by mass.

The nonwoven fabric used in the present invention may contain antioxidants, heat-resistant stabilizers, weather-resistant stabilizers, antistatic agents, slip agents, anti-halation agents, slip agents, dyes, pigments, natural oils, synthetic oils, waxes, fatty acid amide, etc. Various well-known additives. The content rate of these additives in the nonwoven fabric is preferably 0.1 mass% or less, more preferably 0.05 mass% or less, still more preferably 0.01 mass% or less.

The fineness of the long fibers contained in the long fiber nonwoven fabric used in the present invention is not particularly limited as long as the effects of the present invention are achieved, but is preferably 1 to 10 dtex. From the viewpoint of further promoting the interlacing of the first fiber web and the second fiber web and further improving the abrasion resistance, when the long fibers are non-crimped fibers, the latitude of the long fibers is more preferably 3 dtex or more, and further preferably It is more than 5 cents special, and the best one is 5 cents special to 10 cents special. From the viewpoint of further promoting intertwining of fibers and further improving abrasion resistance, when the long fibers are crimped fibers, the latitude of the long fibers is more preferably 7 decitex or less, more preferably 5 decitex or less, and particularly preferably It ranges from 1 cent to 5 cents.

Moreover, as the long fiber, it is preferable to use an eccentric core-sheath type composite long fiber. The reason for this is that the eccentric core-sheath type composite long fiber exhibits crimp due to the difference in shrinkage between the core component and the sheath component and becomes crimped long fiber, and can impart strength and flexibility in the machine direction to the surface material. The reason why the strength becomes better due to the presence of crimped long fibers is not yet certain, but it is believed that the reason is that the crimped long fibers ensure a space inside, and the cotton fibers enter the space and become intertwined. Good tendencies. For example, if a propylene homopolymer component is used as the core component and a propylene·α-olefin copolymer component is used as the sheath component, in the cooling step after melt spinning, the core component and the sheath component will shrink to different degrees, so that Exhibiting spiral curls. The nonwoven fabric used in the present invention may include only non-curled long fibers or only curled long fibers, or may be a mixture of non-curled long fibers and curled long fibers, or may be a layer formed of non-curled long fibers and Made of layers of curly long fibers.

The nonwoven fabric used in the present invention is generally manufactured by the so-called spunbonding method, and preferably is locally hot-pressed to improve the morphological stability. Furthermore, from the perspective of making the coexistence of abrasion resistance and strength more excellent, the unit area weight of the nonwoven fabric is preferably 10g/ ^m2 to 20g/ ^m2 . The long fiber nonwoven fabric can be a single-layer long fiber nonwoven fabric including one layer containing long fibers, or it can be a laminated long fiber nonwoven fabric including two or more layers containing long fibers. The layers included in the laminated long fiber nonwoven fabric can be the same or different.

The first fiber web, the nonwoven fabric, and the second fiber web are sequentially laminated to obtain a first laminated body. In addition, the first fiber web, the second fiber web, and the long fiber nonwoven fabric are sequentially laminated to obtain a second laminated body. High-pressure water flow is applied to the first laminated body or the second laminated body to interweave the fibers in the first fiber web, the long fiber nonwoven fabric, and the second fiber web to obtain fiber velvet. The high-pressure water flow can be applied from either side of the first laminated body or the second laminated body, but is preferably applied from both sides so that the fibers are interwoven as closely as possible.

By applying high-pressure water flow, the fiber velvet contains water. Therefore, it is necessary to dry the fibers to evaporate the water, and during or after the drying step, the heat-fusible short fibers are softened or melted so that the fibers are fused and bonded to each other. For example, when using a concentric core-sheath type composite staple fiber with a core component of polypropylene and a sheath component of polyethylene as the heat-fusible staple fiber, if the drying temperature is set to about 130°C, the water in the fiber velvet will The polyethylene is evaporated and softened or melted, and the fibers are fused and combined with each other to obtain the surface material of the hygienic material.

A representative example of the surface material of a sanitary material obtained using the first laminate is a surface material of a sanitary material in terms of a first fiber web region including cotton fibers, a nonwoven fabric region including long fibers containing a propylene polymer, And the second fiber web region including cotton fibers and thermally fusible short fibers is sequentially laminated and integrated. The cotton fibers in the first fiber web region, the long fibers in the nonwoven region, and the second fibers The cotton fibers and thermally fusible short fibers in the mesh area are intertwined with each other, and the cotton fibers and the long fibers are fused by the thermally fusible short fibers. The thickness is 0.50 mm or less, and the first fiber mesh area is Skin contact. Here, no clear distinction can be made between the regions, but fibers from one region invade other regions. In other words, the layer with more cotton fibers from the first fiber web than other areas becomes the first fiber web area, the layer with more long fibers from non-woven fabric than other areas becomes the non-woven area, and the cotton fibers from the second fiber web and The layer with more thermally fusible short fibers than other areas becomes the second fiber web area. Regarding the number of fibers in each region, the surface material of the sanitary material is cut in the thickness direction, and the cross section is observed with a microscope to count the number of fibers.

The thickness of the surface material of the sanitary material is 0.50 mm or less. When the thickness exceeds 0.50 mm, the interweaving and fusion of cotton fibers in the first fiber web area in contact with the skin become loose, and the wear resistance decreases. The unit area weight of the surface material of the sanitary material is preferably 25 g/m ² to 50 g/m ² , more preferably 35 g/m ² to 50 g/m ² . When the weight per unit area is less than 25 g/m ² , the amount of fibers is small, and therefore the fibers tend not to be sufficiently intertwined with each other. On the other hand, when the weight per unit area exceeds 50 g/ ^m2 , the interweaving and fusion of the cotton fibers in the first fiber web area and the heat-fusible short fibers in the second fiber web area become loose, resulting in wear resistance. tendency to decrease. The air permeability of the surface material of the sanitary material is preferably 100 cm ³ /cm ² /sec to 500 cm ³ /cm ² /sec. When the ventilation rate exceeds 500 cm ³ /cm ² /sec, body fluids temporarily absorbed tend to flow back to the skin side. On the other hand, when the air permeability is less than 100 cm ³ /cm ² /sec, it becomes difficult for body fluids to pass through, that is, the strike through property tends to decrease.

The tensile strength of the surface material of the hygienic material is preferably 15 N/50mm width to 100 N/50mm width in the machine direction, and more preferably 40 N/50mm width to 90 N/50mm width. In addition, the tensile strength in the direction orthogonal to the machine direction (width direction) is preferably 10 N/50 mm width to 50 N/50 mm width. When the tensile strength is less than the lower limit, workability during production of sanitary materials tends to decrease. In addition, when the tensile strength exceeds the upper limit, it becomes an unreasonable surface material with excessive quality. Here, the machine direction refers to the conveyance direction when manufacturing nonwoven fabrics. Therefore, the tensile strength in the machine direction, which is the arrangement direction of the long fibers, is high, and the tensile strength in the width direction is low.

The surface material described above can be used as a surface material for hygienic materials such as sanitary napkins and disposable diapers (especially disposable diapers for infants). Furthermore, the layer with many cotton fibers derived from the first fiber web (the first fiber web area) is used in contact with the skin, so it feels good against the skin.

In the surface material obtained by the method of the present invention, the heat-fusible short fibers contained in the second fiber web penetrate and interweave with the cotton fibers derived from the first fiber web that has a good skin touch due to the action of high-pressure water flow. layer. Therefore, the interweaving of the cotton fibers derived from the first fiber web and the fusion and bonding using the heat-fusible short fibers have the effect of obtaining a surface material excellent in wear resistance. [Example]

Hereinafter, the present invention will be described based on examples. In addition, the following physical properties and characteristics used in this specification are measured by the following measurement method.

(1) Weight per unit area (g/m ² ) Take 10 samples of 100 mm in the machine direction x 100 mm in the width direction from the surface material. Then, the weight of each sample was measured, and the total weight was divided by the total area to calculate the weight per unit area (g/m ² ). (2) Thickness (mm) Use a thickness meter (manufactured by PEACOCK Co., Ltd., product number "R1-250", measuring terminal 25 mmΦ) to measure 5 in the center and four corners of the sample with a load of 7g/ ^m2 point thickness. For the 10-point sample, the thickness was measured using the above method, and the average value was defined as thickness (mm).

(3) Tensile strength in the machine direction (N/50mm width) Take 5 samples of 200 mm in the machine direction x 50 mm in the width direction from the surface material. Then, according to Japanese Industrial Standards (JIS) L 1906, a tensile testing machine (automatic stereograph AGS-J manufactured by Shimadzu Corporation) was used, and the distance between the chucks was 100 mm and the head speed was Under the condition of 300 mm/min, the breaking strength of each sample was measured. The average value of the breaking strengths of the five samples was defined as the tensile strength in the machine direction (N/50mm width). (4) Tensile strength in width direction (N/50mm width) Take 5 samples of 50 mm in the machine direction x 200 mm in the width direction from the surface material. Then, the breaking strength of each sample was measured using the same method as described in (3). The average value of the breaking strengths of the five samples was defined as the tensile strength in the machine direction (N/50mm width).

(5) Air permeability (cm ³ /cm ² /sec) Take 5 samples of 150 mm in the machine direction x 150 mm in the width direction from the surface material. Then, the air permeability was measured with a FRAGILE air permeability measuring machine in accordance with JIS L 1906, and the average value of the 5-point sample was taken as the air permeability (cm ³ /cm ² /sec). (6) Show-through (sec) Take 10 samples of 100 mm in the machine direction x 100 mm in the width direction from the surface material. According to European Disposables and Nonwovens Association (EDANA) 150.3-96, the print-through measuring device manufactured by LENTING Company was used for measurement. That is, one sample and five pieces of filter paper (grade 989, manufactured by Intec) of the same size as the sample were overlapped and placed in the measuring device, and then 5 ml of distilled water was delivered and the time required for absorption was measured. This was used as the first time, and the second and third times were carried out without changing the filter paper. Each time, 5 ml of distilled water was delivered, and the time required for each was measured. Replace the sample and filter paper, and measure the time required for each of the remaining 9 samples using the same method. Set the average of all required times to showthrough (sec).

(7) Wear resistance (times) From the surface material, 50 samples with a length of 220 mm and a width of 30 mm were taken in random directions. In accordance with JIS L 0849, place the sample at point 6 on a Gakushin-type friction fastness testing machine (RT-300S, manufactured by Daiei Science Seiki Seisakusho Co., Ltd.) with the first fiber mesh surface becoming the friction terminal side. And measure the wear resistance. That is, use white cotton cloth for friction on the surface of the friction terminal, use #200 sandpaper on the base material, slide the friction terminal at a reciprocation speed of 30 times/min, and measure the number of reciprocations when fiber peeling can be visually seen in all 6 samples. Then, the above-mentioned measurement was performed five times, the number of reciprocations was measured, and the average value was taken as the wear resistance (times). (8) Flexibility (mm) Take 5 samples of 150 mm in the machine direction x 20 mm in the width direction from the surface material, and 5 samples of 150 mm in the width direction x 20 mm in the machine direction. Using the sample, the softness (mm) was measured in accordance with JIS L 1096 (6.19.1 A regulations) in a constant temperature room with a temperature of 20±2°C and a humidity of 65±2%. That is, the short side of the sample was aligned with the base line of the scale and placed on a smooth horizontal platform having a 45° slope. Then, manually slide the sample slowly in the direction of the slope, and use a scale to measure the movement length (mm) of the other end position when the center point of one end of the sample contacts the slope. For a 1-point sample, measure the moving length (mm) on the front and back. The movement length (mm) was measured for 10 samples, and the average value of 20 movement lengths (mm) was defined as flexibility (mm).

Example 1 [Preparation of the first fiber web] Bleached cotton with an average fiber length of 25 mm was opened and aggregated using a parallel carding machine to obtain a first fiber web with a weight per unit area of 17 g/ ^m2 .

[Preparation of the second fiber web] As the heat-fusible staple fiber, a concentric core-sheath type composite short fiber was used, whose sheath component was polyethylene with a melting point of 130°C and whose core component was polyethylene terephthalate with a melting point of 260°C. (Manufactured by UNITIKA Co., Ltd., fineness 2.2 decitex, fiber length 51 mm). Then, 50% by mass of bleached cotton with an average fiber length of 25 mm and 50% by mass of the heat-fusible short fibers were uniformly mixed, and a random card machine was used to open and aggregate the fibers to obtain the weight per unit area. Secondary fiber web of 15 g/ ^m2 .

[Preparation of nonwoven fabrics] Use a melting point of 162°C and an MFR of 30 g/10 minutes (MFR is measured in accordance with American Society of Testing Materials (ASTM) D1238, at a temperature of 230°C and a load of 2.16 kg. Below, the same as MFR The measurement method is the same as that of propylene homopolymer, which is melt-spun by the spunbonding method. Long fibers with a fineness of 6.6 decitex are gathered on the collection surface and then partially crimped to obtain a total crimped area of 18%. Long fiber nonwoven fabric with a weight per unit area of 13 g/ ^m2 .

The first fiber web, nonwoven fabric and second fiber web prepared in the above are sequentially laminated to obtain a first laminated body. The first laminated body is placed on a steel conveyor belt and transported, and a high-pressure water jetting device (a device in which jetting holes with a hole diameter of 0.1 mm are arranged in a horizontal line with a hole interval of 0.6 mm) is used to eject the water from the second fiber A high-pressure water flow is applied to the mesh side with a spray pressure of 3 MPa, and then a high-pressure water flow is applied with a spray pressure of 6 MPa. Then, a high-pressure water flow was applied from the first fiber web side with a jet pressure of 6 MPa, thereby obtaining fiber velvet. The fiber velvet is heated at 120° C. for 120 seconds to evaporate the water in the fiber velvet, and only the polyethylene of the concentric core-sheath type composite short fibers is softened or melted, thereby obtaining a surface material in which the fibers are fused to each other.

Example 2 A surface material was obtained in the same manner as in Example 1, except that the mass ratio of bleached cotton and heat-fusible short fibers in the second fiber web was changed to 70 mass% of bleached cotton and 30 mass% of heat-fusible short fibers.

Example 3 In Example 1, a surface material was obtained in the same manner as in Example 1, except that the heating temperature of the fiber velvet was changed to 135°C instead of 120°C.

Example 4 In Example 1, a surface material was obtained in the same manner as in Example 1, except that a 15-inch mesh conveyor belt was used instead of the steel conveyor belt that conveyed the first laminated body.

Example 5 A surface material was obtained in the same manner as in Example 1, except that a nonwoven fabric prepared by the method described below was used instead of the nonwoven fabric used in Example 1. [Preparation of nonwoven fabric] Using a propylene homopolymer with a melting point of 162°C and an MFR of 60 g/10 minutes, melt spinning was carried out by the spunbonding method, and long fibers with a fineness of 1.7 dtex were gathered on the collection surface to obtain unit area First long fiber web with a weight of 4 g/ ^m2 . Next, a propylene-ethylene random copolymer (ethylene content 5.0 mol%) with a melting point of 140°C and an MFR of 60 g/10 minutes was used as the sheath component, and the propylene homopolymer was used as the core component. Composite melt spinning is performed, and eccentric core-sheath type composite long fibers with a fineness of 1.7 decitex and a core component:sheath component = 20:80 (mass ratio) are gathered on the first fiber web. The weight per unit area of the web containing the aggregated eccentric core-sheath type composite long fibers is 5 g/m ² . Then, using the same method as when obtaining the first long fiber web, the second long fiber web is gathered on the web containing the eccentric core-sheath type composite long fibers, thereby obtaining the first long fiber web, including the eccentric core-sheath type composite long fibers. The fiber web and the second long fiber web are laminated in sequence to form a laminated long fiber nonwoven fabric with a weight per unit area of 13 g/ ^m2 . Furthermore, the eccentric core-sheath type composite long fiber exhibits curl.

Comparative example 1 In Example 1, a surface material was obtained by the same method as Example 1, except that nonwoven fabric was not used.

Comparative Example 2 A surface material was obtained in the same manner as in Example 1, except that a nonwoven fabric prepared by the method described below was used instead of the nonwoven fabric used in Example 1. [Preparation of nonwoven fabric] Ethylene·1-butene copolymer [manufactured by PRIME POLYMER, product name "NEO-ZEX NZ50301", density 0.950 g/cm ³ , MFR (measured in accordance with ASTM D1238 at a temperature of 190°C and a load of 2.16 kg) 30 g/min] as the sheath component, and polyethylene terephthalate (manufactured by Mitsui Chemicals, product name "J125") as the core The composite melt spinning was carried out at a resin temperature of 270°C and a single hole ejection rate of 0.5 g/min/hole, followed by cooling and stretching to obtain a fineness of core component: sheath component = 50:50 (mass ratio) 2 dtex concentric core-sheath type composite long fiber. After the concentric core-sheath type composite long fibers were gathered into a sheet, heat embossing was performed to obtain a nonwoven fabric with a weight per unit area of 16 g/m ² .

Comparative Example 3 A surface material was obtained in the same manner as in Example 1, except that a second fiber web prepared by the method described below was used instead of the second fiber web used in Example 1. [Preparation of the second fiber web] 100% by mass of bleached cotton with an average fiber length of 25 mm is uniformly mixed, and fiber opening and aggregation are performed using a random carding machine to obtain a second fiber web with a weight per unit area of 15 g/m ² .

The physical properties of the surface materials obtained in Examples 1 to 5 and Comparative Examples 1 to 3 are shown in Table 1, and their characteristics are shown in Table 2. [Table 1] Weight per unit area (g/m ² ) Thickness(mm) Tensile strength in machine direction (N/50mm width) Tensile strength in width direction (N/50mm width) Example 1 45 0.36 73 28 Example 2 45 0.41 66 38 Example 3 45 0.40 76 29 Example 4 45 0.45 74 29 Example 5 45 0.44 81 31 Comparative example 1 32 0.29 13 9 Comparative example 2 48 0.33 85 34 Comparative example 3 45 0.42 58 40 [Table 2] Ventilation (cm ³ /cm ² /sec) Print through (sec) Wear resistance (times) Softness(mm) Example 1 144 4.6 55 42 Example 2 139 4.0 50 43 Example 3 126 4.4 63 48 Example 4 188 3.8 58 46 Example 5 121 4.7 57 35 Comparative example 1 230 3.8 62 41 Comparative example 2 201 3.8 45 68 Comparative example 3 130 4.3 38 44

According to Table 1 and Table 2, compared with the surface material obtained in the Example, the surface material obtained in Comparative Example 1 does not use non-woven fabric, so the tensile strength in the machine direction and the width direction is extremely low. In the processing of sanitary materials It may break or become unusable during manufacturing. In addition, since the surface material obtained in Comparative Example 2 was not made of a propylene-based polymer, the surface material lacked flexibility and had a poor touch against the skin. Furthermore, since the surface material obtained in Comparative Example 3 did not use heat-fusible short fibers, the wear resistance deteriorated.

Example 6 [Preparation of the first fiber web] The same first fiber web as used in Example 1 was obtained.

[Preparation of the second fiber web] As the heat-fusible short fiber, a concentric core-sheath type composite short fiber (Ube Ekusimo (Ube Ekusimo)) was used. Manufactured by UBE EXSYMO Co., Ltd., fineness 2.2 decitex, fiber length 51 mm). Then, 50% by mass of non-degreasing bleached cotton with an average fiber length of 25 mm and 50% by mass of the heat-fusible short fibers were uniformly mixed, and a random carding machine was used to open and aggregate the fibers, thereby obtaining a weight per unit area of 15 g/ m ² second fiber web.

[Preparation of nonwoven fabrics] Use a propylene homopolymer with a melting point of 162°C and MFR 60g/10 minutes. Melt spinning is performed by the spunbonding method. Long fibers with a fineness of 1.7 dtex are gathered on the collection surface to obtain the weight per unit area. 5g/ ^m2 first long fiber web. Next, a propylene-ethylene random copolymer (ethylene content 5.0 mol%) with a melting point of 140°C and an MFR of 60 g/10 minutes was used as the sheath component, and the propylene homopolymer was used as the core component, and the spun bonding method was used. Composite melt spinning is performed, and eccentric core-sheath type composite long fibers with a fineness of 1.7 decitex and a core component: sheath component = 20:80 (mass ratio) are gathered on the first fiber web. The weight per unit area of the web containing the aggregated eccentric core-sheath type composite long fibers is 7 g/m ² . Then, using the same method as when obtaining the first long fiber web, the second long fiber web is gathered on the web containing the eccentric core-sheath type composite long fibers, thereby obtaining the first long fiber web, including the eccentric core-sheath type composite long fibers. The fiber web and the second long fiber web are laminated in sequence to form a laminated long fiber nonwoven fabric with a weight per unit area of 17 g/ ^m2 . Furthermore, the eccentric core-sheath type composite long fiber exhibits curl.

The prepared first fiber web, nonwoven fabric and second fiber web are sequentially laminated to obtain a first laminated body. The first laminated body was passed through the high-pressure water jetting device used in Example 3 to obtain fiber velvet under the same conditions as Example 3, and a surface material was obtained under the same conditions as Example 3.

Example 7 The first fiber web prepared in Example 1, the second fiber web prepared in Example 1, and the long fiber nonwoven fabric prepared in Example 1 were laminated in this order to obtain a second laminated body. The second laminated body was passed through the high-pressure water jet device used in Example 1, and a high-pressure water jet was applied from the first fiber web side at a jet pressure of 3 MPa, and then a high-pressure water jet was applied at a jet pressure of 6 MPa. Then, high-pressure water flow is applied from the long-fiber nonwoven fabric side with a jet pressure of 6 MPa to obtain fiber velvet. The fiber velvet is heated at 135° C. for 120 seconds to evaporate the water in the fiber velvet, and only the polyethylene of the concentric core-sheath type composite short fibers is softened or melted, thereby obtaining a surface material in which the fibers are fused to each other.

Example 8 A surface material was obtained in the same manner as in Example 3, except that a nonwoven fabric prepared by the method described below was used instead of the nonwoven fabric used in Example 3. [Preparation of long-fiber nonwoven fabric] As a sheath component, a propylene-ethylene random copolymer (ethylene content: 5.0 mol%) with a melting point of 140°C and an MFR of 60 g/10 minutes was used. The propylene homopolymer is used as the core component, and composite melt spinning is carried out by the spunbonding method, and the eccentric core-sheath type composite long fiber with a core component: sheath component = 20:80 (mass ratio) with a fineness of 1.7 decitex is gathered. The collection surface is used to obtain a long fiber nonwoven fabric with a weight per unit area of 20 g/ ^m2 . Furthermore, the eccentric core-sheath type composite long fibers in long-fiber nonwoven fabrics exhibit curl.

The wear resistance of the surface materials obtained in Examples 6 to 8 was measured. In Example 6, it was 30 times, in Example 7, it was 80 times, and in Example 8, it was 73 times. Therefore, it is found that the surface material obtained in Examples 6 to 8 has excellent abrasion resistance on the surface in contact with the skin.

without

without

Claims (13)

A method of manufacturing a surface material for sanitary materials, characterized in that: a first fiber web including cotton fibers, a nonwoven fabric including long fibers containing a propylene polymer, and a second fiber including cotton fibers and thermally fusible short fibers A high-pressure water flow is applied to the first laminate in which the nets are sequentially laminated to interweave the cotton fibers, the heat-fusible short fibers, and the long fibers to obtain fiber velvet, and then the fiber velvet is heated to make the fiber velvet. The surface of the thermally fusible short fibers is softened or melted, thereby using the thermally fusible short fibers to combine the cotton fibers and the long fibers with each other, wherein the first fiber web side is in contact with the skin. A method of manufacturing a surface material for hygienic materials, characterized by: a first fiber web including cotton fibers, a second fiber web including cotton fibers and heat-fusible short fibers, and a long fiber containing a propylene polymer. A high-pressure water flow is applied to a second laminate in which nonwoven fabrics are sequentially laminated to interweave the cotton fibers, the heat-fusible short fibers, and the long fibers to obtain fiber velvet, and then the fiber velvet is heated to make The surface of the thermally fusible short fibers is softened or melted, thereby using the thermally fusible short fibers to combine the cotton fibers and the long fibers with each other, wherein the first fiber web side is in contact with the skin. The method for manufacturing a surface material for sanitary materials according to Claim 1 or Claim 2, wherein the cotton fiber is not degreased and has been bleached. The method of manufacturing a surface material for sanitary materials according to claim 1 or claim 2, wherein the heat-fusible short fibers are concentric core-sheath type composite short fibers, and the melting point of the sheath component is lower than the melting point of the core component. The method for manufacturing a surface material for sanitary materials according to claim 1 or claim 2, wherein the nonwoven fabric contains eccentric core-sheath type composite long fibers, and the eccentric core-sheath type composite long fibers exhibit curl. A surface material for sanitary materials in which a first fiber web region including cotton fibers, a nonwoven fabric region including long fibers containing a propylene-based polymer, and a second fiber web region including cotton fibers and heat-fusible short fibers are laminated in this order. Integrated, the cotton fibers in the first fiber web area, the long fibers in the non-woven fabric area, and the cotton fibers and heat-fusible short fibers in the second fiber web area are intertwined, and the cotton The fibers and the long fibers are fused by the heat-fusible short fibers, and the thickness of the surface material of the sanitary material is 0.50 mm or less, and the first fiber web area is in contact with the skin. The surface material of sanitary materials as described in claim 6 has a unit area weight of 25g/m ² ~50g/m ² . The surface material of the hygienic material as described in claim 6 or claim 7 has an air permeability of 100cm ³ /cm ² /sec~500cm ³ /cm ² /sec. The surface material of sanitary material according to claim 6 or claim 7, wherein the tensile strength in the machine direction is 15N/50mm width to 100N/50mm width. The surface material of sanitary material according to claim 6 or claim 7, wherein the tensile strength in the direction orthogonal to the machine direction is 10N/50mm width to 50N/50mm width. The surface material of sanitary material according to claim 6 or claim 7, wherein the thermally fusible short fibers are concentric core-sheath type composite short fibers. The sanitary material surface material according to Claim 11, wherein the core of the heat-fusible short fiber contains polyethylene terephthalate or polypropylene, and the sheath contains polyethylene. The surface material of sanitary material according to claim 6 or claim 7, wherein the long fibers are eccentric core-sheath type composite long fibers.