JP2005246812A - Composite sheet and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite sheet having a simple structure and excellent in flexibility and touch. <P>SOLUTION: The composite sheet is composed of a first sheet 2 having a large number of holes 21 arranged thereto and the second sheet 4 bonded to the first sheet 2 through an adhesive. Undulations having the bonded part 22 with the second sheet 4 and erected parts 23 erected without being bonded to the second sheet 4 are provided to the peripheral parts of the respective holes 21 of the first sheet 2. The first sheet 2 is an air-through nonwoven fabric and the second sheet 4 is a nonwoven fabric including spun bonded parts. The second sheet 4 is preferably a nonwoven fabric wherein the spun bonded parts and melt blown parts are combined. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a composite sheet, and relates to a composite sheet applicable to a wide range of applications such as absorbent articles and various wiping sheets, and a method for producing the same.

  As a prior art regarding the composite sheet used for the absorbent article, for example, a technique described in Patent Document 1 below is known. In this technique, a nonwoven fabric and a resin film are laminated, and holes are formed in these to obtain a laminate having elasticity. However, this laminate has a simple structure but does not have an excellent texture.

JP 11-291372 A

  Accordingly, an object of the present invention is to provide a composite sheet that can eliminate the above-described disadvantages of the composite sheet of the prior art and a method for manufacturing the composite sheet.

  The present invention comprises a first sheet in which a large number of holes are disposed, and a second sheet joined to the first sheet via an adhesive, and is provided at the periphery of each hole of the first sheet. The composite sheet is provided with a undulation having a joint portion with the second sheet and an upright portion that stands up without being joined with the second sheet, and the first sheet is an air-through nonwoven fabric, The above object is achieved by providing a composite sheet in which the second sheet is a nonwoven fabric containing spunbond.

  In the present invention, after forming a first sheet by arranging a large number of holes in the air-through nonwoven fabric and applying tension to the first sheet so that the holes spread, the peripheral part of the holes is undulated. First, an adhesive is applied to a convex portion on one side of the first sheet formed along with the undulation of the peripheral portion, and the first sheet and a non-woven fabric containing a spunbond are interposed through the adhesive. The object is achieved by providing a method for producing a composite sheet for joining two sheets.

  The composite sheet of the present invention is flexible and excellent in texture. In addition, since the composite sheet of the present invention is flexible and excellent in texture, and has a simple structure, it can be applied to a wide range of applications by selecting the material of the sheet. According to the method for producing a composite sheet of the present invention, it is possible to easily obtain a composite sheet that is rich in undulations and is flexible and excellent in texture.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings.

  FIG.1 and FIG.2 shows typically one Embodiment of the composite sheet of this invention. In these drawings, reference numeral 1 denotes a composite sheet.

  The composite sheet 1 includes a first sheet 2 provided with a large number of holes 21 and a second sheet 4 joined to the first sheet 2 via an adhesive 3. In the peripheral part of each hole 21 of the first sheet 2, there is provided a undulation having a joining part 22 with the second sheet 4 and a standing part 23 that stands up without joining to the second sheet 4. The many holes 21 are arranged in a staggered arrangement (alternately) as shown in FIG.

  As will be described later, in the composite sheet 1, the first sheet 2 is formed with tension applied to the first sheet 2 so as to widen the hole 21, and the peripheral portion of the hole 21 is undulated. The adhesive 3 is applied to the convex portion on one side of the first sheet 2, and the first sheet 2 is bonded to the second sheet 4 at the bonding portion 22 via the adhesive 3, and undulations are provided in the peripheral portion of the hole. .

  On the surface of the composite sheet 1 on the first sheet 2 side, a fold-like or pile-like standing part 23 is formed as a reverse of the concave part formed by applying tension so as to widen the hole 21. The upright portions 23 provide flexibility and texture peculiar to the composite sheet 1.

  As shown in FIG. 2A, the undulating state of the peripheral portion of the hole 21 is a case where the joint portion 22 is formed between the holes 21 and the peripheral portions of the holes 21 are both raised portions 23, or B in FIG. As shown in FIG. 3, the peripheral portion of one hole 21 may be the joint portion 22 and the other may be the standing portion 23.

  The composite sheet of the present invention may have another sheet in addition to the first sheet and the second sheet, and the first sheet 2 in the second sheet 4 like the composite sheet 1 of the present embodiment. The 3rd sheet 5 may be joined to the field where is not joined.

The basis weight of the composite sheet 1 is 10 to 100 g / m ² , particularly 10 to 10 g / m ² from the viewpoint of giving a good texture and flexibility, having sufficient strength in use, and realizing it at an economical cost. 80 g / m ² is preferable.

The thickness of the composite sheet 1 is preferably 0.1 to 5.0 mm, particularly preferably 0.5 to 2.0 mm, from the viewpoint of obtaining a tactile sensation like a towel, soft softness, and fluffy raised feeling. Here, the thickness of the composite sheet 1 is measured by a laser displacement meter while applying a load of 0.5 cN / cm ² .

  The buckling strength of the composite sheet 1 is 50 cN or less in consideration of the softness of the entire product when applied to a product such as an absorbent article, the softness of the gathering portion, the softness of the softness, the texture, etc. It is preferable to set it as 10-40 cN. Here, as shown below, the buckling strength is measured as follows by a compression test mode of a universal testing apparatus (manufactured by Orientec, “Tensilon”, the same shall apply hereinafter).

<Buckling strength test method (CD)>
Take a rectangular test piece of 150 mm in the machine flow direction (MD) and 30 mm in the direction perpendicular to the machine flow (CD) to make a cylinder with a diameter of 45 mm with the surface side of the first sheet as the outside. The upper and lower ends of the sample are stopped with a stapler or the like to obtain a measurement sample. This is measured at a measurement environment of 20 ° C., 65% RH, and measurement conditions of a compression speed of 10 mm / min and a measurement distance of 20 mm in the compression test mode of the universal testing apparatus. The maximum strength when the sample is compressed by 20 mm is measured for each sample, the average value is obtained, and this is taken as the buckling strength.

  The compression stiffness of the composite sheet 1 is preferably 0.2 to 0.6, particularly preferably 0.2 to 0.5, from the viewpoint of obtaining softness and a fluffy raised feeling. Here, the compression stiffness is measured by “KES-FB3” manufactured by Kato Tech Co., Ltd. by the following method.

<Measurement method of compression stiffness>
A test piece of 20 cm × 20 cm is prepared and attached to a test bench. The specimen is compressed between steel plates having a circular plane with an area of 2 cm ² . The compression speed is 20 μm / s, the maximum compression load is 4.9 kPa, and the recovery process is performed at the same speed. The compression stiffness is expressed as an LC value. This LC value is defined as the following formula (1).

  The roughness of the composite sheet 1 is preferably 3 to 15 μm, particularly 5 to 12 μm, from the viewpoint of obtaining a tactile feel like a towel and a fluffy feeling without stickiness. Here, the roughness is measured as follows using “KES-FB4” manufactured by Kato Tech Co., Ltd.

<Roughness measurement method>
A test piece of 20 cm × 20 cm is prepared and attached to a smooth metal flat test bench. The test piece is pressure-bonded with a contact of 9.8 cN (error within ± 0.49 cN), and the test piece is moved 2 cm horizontally at a constant speed of 0.1 cm / s. The specimen is given a uniaxial tension of 19.6 cN / cm. The contact is bent into a U shape with a 0.5 mm diameter piano wire, and the test piece is pressure-bonded at 9.8 cN. This contact is pressure-bonded by a spring. The constant of the spring is 24.5 cN / mm (within an error of ± 0.98 cN / mm), and the resonance frequency is 30 Hz or more in a state of being separated from the surface contact. The measured roughness value is expressed as an SMD value. This measurement is performed for both MD and CD, and an average value is obtained by the following formula (2), which is defined as roughness.
Roughness = {(SMD _MD ² + SMD _CD ² ) / 2} ^1/2 (2)

The number per unit area of the upright portions 23 on the surface of the composite sheet 1 on the first sheet 2 side is appropriately set according to the use, the touch for the purpose, and the appearance. From the viewpoint of obtaining a soft tactile sensation, a soft appearance, and a raised feeling, the number of the standing parts 23 is preferably 5 to 100 / cm ² , particularly preferably 10 to 50 / cm ² .
The height H (see FIG. 2) of the upright portion 23 is 0.05 to 4.95 mm, particularly 0.45 to 1.95 mm, from the viewpoint of obtaining a tactile sensation such as a towel, soft softness, and fluffy feeling. It is preferable that

It is preferable that the composite sheet 1 has moisture permeability. The moisture permeability of the composite sheet 1 in this case is appropriately set according to the application and purpose. The moisture permeability is 0.5 to 4.0 g / (100 cm ² · h), particularly from the point of releasing moisture sufficiently to suppress stuffiness and fogging when used as an outer layer material of an absorbent article. It is preferable to set it as 1.0-3.0 g / (100 cm < ² > * h). Here, the moisture permeability is measured as follows according to the cup method in accordance with JIS Z0208.

<Moisture permeability measurement method>
The measurement of moisture permeability is performed by the cup method according to JIS Z0208. The temperature and humidity conditions for the test are 30 ± 0.5 ° C. and 90 ± 2% RH. A cup having an inner diameter of 60 mm and an area of 28.27 cm ² is used. Calcium chloride is used as a hygroscopic agent, and 18 g is put in the cup. The measurement sample is a circular sample having a diameter of 70 mm. The measurement is performed by attaching the test piece to a cup, sealing the periphery with a sealing agent, and placing the test piece in a constant temperature and humidity device. The weight before the addition is defined as W0, and it is placed in a constant temperature and humidity apparatus (30 ± 0.5 ° C., 90 ± 2% RH) for 1 hour, and the weight after removal is defined as W1. The measured value of moisture permeability is expressed by the following formula (3).
Moisture permeability [g / (100 cm ² · h)] = (W1−W0) × 100 / 28.27 (3)

When the composite sheet 1 uses a porous sheet as the third sheet 5 as will be described later, the composite sheet 1 itself also has moisture-permeable and leak-proof properties. The moisture permeability of the composite sheet 1 in this case is appropriately set according to the application and purpose. When the composite sheet is used as an outer layer material of an absorbent article, the moisture permeability is sufficient to release moisture to suppress stuffiness and fogging, and to leak moisture and moisture to the outside and wet clothes, etc. In view of having sufficient water resistance, it is preferably 0.5 to 4.0 g / (100 cm ² · h), more preferably 1.0 to 3.0 g / (100 cm ² · h). Furthermore, regarding leakage prevention, when used as an outer layer material of an absorbent article, moisture and moisture are not leaked outside and do not wet clothes, so that the water pressure resistance is 9.8 kPa or more, particularly 19.6 kPa. The above is preferable. Here, the water pressure resistance is measured as follows in accordance with JIS L1092, the hydrostatic pressure method, and the method A (low pressure method).

<Water pressure measurement method>
A 15 × 15 cm test piece is taken, and the test piece is brought into contact with water, and on the opposite side of the test piece, a filter paper and a metal mesh are overlapped and attached to the test apparatus. Colored physiological saline is added to a water pressure gauge (manometer) to raise the water level, and seepage to the filter paper at a water level of 1 m (9.8 kPa) and 2 m (19.6 kPa) is confirmed. If it is confirmed that there is no exudation, it is assumed that there is a water pressure resistance higher than the water level (pressure).

  The material of the first sheet 2 is an air-through nonwoven fabric. As the fibers constituting the nonwoven fabric, polyolefin fibers such as resins mainly composed of polyethylene, polypropylene, or propylene-ethylene random copolymer, polyethylene terephthalate fibers, polyamide fibers, and the like are preferable. Among these, polyolefin fibers Is preferred. The fiber structure may be a single fiber, a core-sheath fiber, or a side-by-side fiber, and the use of a composite fiber or a mixed fiber is preferable for further improving the texture and touch. In particular, a core-sheath fiber in which polyethylene terephthalate is a core, polyethylene is a sheath, and a core-sheath fiber in which polypropylene is a core and polyethylene is a sheath are particularly preferable in terms of texture. The fiber diameter is preferably 0.5 to 3.0 dtex, particularly 0.5 to 2.0 dtex from the viewpoint of texture. From the viewpoint of imparting leakage prevention to the nonwoven fabric, the fibers are preferably hydrophobic.

The basis weight of the first sheet 2 (basis weight before applying the tension) gives a good texture and flexibility, has sufficient strength in use, and realizes it at an economical cost. Is preferably 5 to 50 g / m ² , particularly preferably 5 to 30 g / m ² .

  The thickness of the first sheet 2 (thickness before applying the tension) can be appropriately set according to the application and purpose. However, from the viewpoint of obtaining a tactile feel like a towel and a fluffy raised feeling, 0.1 ˜5.0 mm, particularly preferably 0.2 to 2.0 mm.

  The MD breaking strength of the first sheet 2 (before the numerous holes 21 are disposed) is 10 to 100 N / 50 mm from the viewpoint of stretch opening property, uneven shape standing property, and stretch sheet workability. In particular, it is preferably 15 to 75 N / 50 mm. Here, the breaking strength is measured as follows by the tensile test mode of the universal testing apparatus, for example, as shown below.

<MD breaking strength test method>
A rectangular test piece of 200 mm in the machine flow direction (MD) and 50 mm in the direction perpendicular to the machine flow (CD) is prepared. This is measured at a measurement environment of 20 ° C., 65% RH, with a tensile speed of 300 mm / min and an inter-measurement distance of 150 mm in the tensile test mode of the universal testing device.

The number per unit area of the holes 21 provided in the first sheet 2 before applying the tension depends on the number per unit area of the standing portion of the surface of the composite sheet 1 on the first sheet 2 side. Set as appropriate. The number is 1 to 50 pieces / cm ² , particularly 1 to 25 pieces / cm ² , from the viewpoint of easy formation of standing parts, soft touch of the composite sheet 1, softness of appearance, and raising feeling. It is preferable that

  The form of the hole 21 disposed in the first sheet 2 (the form before applying the tension) is not particularly limited as long as the undulation can be provided. Examples of the shape of the hole 21 include a slit shape, a circular shape, an elliptical shape, an oval shape, a convex lens shape, a rectangular shape, a rhombus shape, a polygonal shape, and the like. A slit-like form and an axially symmetric form having a line-symmetrical axis (hereinafter referred to as a symmetric axis) are preferable from the viewpoints of further enhancing the stretch openability and raising the standing part. In particular, the slit-like hole is preferable in that the standing part of the peripheral part can be enlarged in a pleat shape or a pile shape when tension is applied.

  Length of one hole 21 before the tension is applied (if the hole is slit-shaped, the length is the same; if the hole is axially symmetric, it is the maximum length on the axis of symmetry) L1 (see FIG. 3) Is appropriately set according to the type, material, thickness, and basis weight of the first sheet. The length L1 is preferably set to 0.5 to 10 mm, particularly 1 to 5 mm from the viewpoint of obtaining the size of the fold-like or pile-like standing portion, the touch feeling like a towel, and the fluffy feeling of raising.

  The many holes 21 arranged in the first sheet 2 only need to be able to form standing parts by tension, and the manner of arrangement of each hole can be arbitrarily selected. From the viewpoint of easy formation of the upright portions and the ability to form a uniform upright portion, it is preferable that the holes form a line in a straight line intersecting the direction F in which the tension is applied. In particular, it is more preferable that the holes in each row are shifted in the direction F with respect to the holes formed in the adjacent rows, and a staggered arrangement in which the hole portions and the non-hole portions are alternately arranged. .

  Further, the interval L2 (see FIG. 3) between the holes 21 in one row before applying the tension is appropriately set according to the type and material of the first sheet. The distance is 0.5 to 10 mm, especially 1 to 5 in consideration of the ease of forming a fold-like or pile-like standing portion, the sheet breakage at the time of stretch opening, stretch pore opening property, ease of stretching, and the like. 5 mm is preferable.

  Before applying the tension, the interval between adjacent rows of holes 21 (interval between adjacent portions of adjacent rows) L3 (see FIG. 3) is appropriately set according to the type and material of the first sheet. Is done. The distance is 0.5 to 10 mm, especially 1 to 5 in consideration of the ease of forming a fold-like or pile-like standing portion, the sheet breakage at the time of stretch opening, stretch pore opening property, ease of stretching, and the like. 5 mm is preferable.

  Before applying the tension, it is preferable that the holes 21 arranged in adjacent rows of the first sheet 2 are arranged so as to overlap each other when projected onto one of the rows. By setting it as such an arrangement | positioning form, the 1st sheet | seat 2 becomes easy to expand | extend and the standing part 23 of the peripheral part of the hole 21 can be enlarged in the shape of a pleat or a pile. The length L4 (see FIG. 3) where the holes overlap each other is appropriately set according to the type and material of the first sheet. The length L4 is in the range of 0 to 4.5 mm, particularly 0, considering the ease of forming a pleated or pile-like standing portion, the sheet breakage at the time of stretch opening, stretch pore opening property, ease of stretching, and the like. It is preferable to be set to ˜2 mm.

  Before applying the tension, the length direction of the holes 21 (in the case of slit-like holes, the length direction thereof, in the case of an axially symmetric form, the direction of symmetry axis) is aligned with the row direction R. However, as indicated by the alternate long and short dash line in FIG. 3, it may have a predetermined angle with respect to the direction R of the row, or a combination thereof. The angle θ (see FIG. 3) formed with the length direction of the hole 21 is appropriately set according to the type and material of the first sheet. The angle is preferably within ± 10 degrees in consideration of uniform stretch-opening property and ease of forming pleated or pile-like undulations.

  Before the tension is applied, the direction R of the row of the holes 21 is preferably aligned with a direction substantially orthogonal to the direction F of applying the tension (see FIG. 3). By aligning the holes 21 in such a direction, it can be easily extended, and a fold-like or pile-like standing portion can be formed. It should be noted that the row direction R can also be provided so as to intersect the direction F of applying the tension at an angle α within a range not impairing the effects of the present invention. The angle α is preferably 80 to 100 degrees.

For the second sheet 4, a nonwoven fabric containing spunbond is used. Examples of the nonwoven fabric include a spunbond monolayer, a spunbond-only nonwoven fabric in which spunbonds are laminated, and a nonwoven fabric in which a spunbond and a meltblown are combined to form a single layer. From the viewpoint of making the second sheet 4 thin and having high strength, it is preferable to use a nonwoven fabric formed by combining a spunbond and a meltblown. Examples of the nonwoven fabric formed by combining the spunbond (S) and the melt blown (M) include SMS, SM, SMMS, and SSMMS nonwoven fabric. In particular, by using the SMS nonwoven fabric, the second sheet 4 is thin and flexible, has a sufficient strength even when it is thin, and has a good longitudinal and lateral strength balance. The fibers constituting the non-woven fabric containing the spunbond are preferably polyolefin fibers such as resins mainly composed of polyethylene, polypropylene, or propylene-ethylene random copolymer, polyethylene terephthalate fibers, or polyamide fibers. Among these, Polyolefin fibers are preferred. The fiber structure may be a single fiber, or a composite fiber such as a core-sheath fiber or a side-by-side fiber. Fibers using a propylene-ethylene random copolymer, core-sheath fibers in which polyethylene terephthalate is the core, polyethylene is the sheath, and core-sheath fibers in which the core is polyethylene and the sheath is polyethylene, especially the texture and touch are further improved Preferred above. The fiber diameter is preferably 0.5 to 3.0 dtex, particularly 0.5 to 2.0 dtex from the viewpoint of texture. From the viewpoint of imparting leakage prevention to the nonwoven fabric, the fibers are preferably hydrophobic. The nonwoven fabric fiber may be the same material as the first sheet 2 or a different material.

The basis weight of the second sheet 4 has a good texture and flexibility, has sufficient strength in use, and in view of realizing it at an economical cost, 5 to 30 g / m ² , In particular, it is preferably 5 to ²⁰ g / m ² .

  The thickness of the second sheet 4 has a good texture and flexibility, has sufficient strength in use, and 0.05 to 1.0 mm, particularly in terms of realizing it at an economical cost, It is preferable to set it as 0.1-0.5 mm.

The moisture permeability of the second sheet 4 is appropriately set according to the application and purpose. The moisture permeability is 0.5 to 4.0 g / (100 cm ² · h), particularly from the point of releasing moisture sufficiently to suppress stuffiness and fogging when used as an outer layer material of an absorbent article. It is preferable to set it as 1.0-3.0 g / (100 cm < ² > * h).

  The second sheet 4 can be subjected to embossing, perforating, printing, various texture improving processes, and the like.

There is no restriction | limiting in particular in the embossing pattern of the said embossing, For example, a polka dot pattern, a lattice pattern, a diagonal lattice pattern, a dot pattern, a picture pattern etc., the combination pattern, etc. are mentioned. Further, the embossed area in the embossing is preferably 1 to 50% and more preferably 3 to 30% in consideration of appearance, strength, texture, and air permeability.
The perforating process is not particularly limited, and includes a method of preheating the sheet and opening it by applying a negative pressure, a method of providing a hole in the sheet with a heated or non-heated needle, and a protrusion. Examples thereof include a method of providing an opening with an embossing roll.
The printing process is not particularly limited, and examples include gravure printing, flexographic printing, offset printing, screen printing, and ink jet printing.

  The material of the adhesive 3 is particularly preferably a hot-melt type adhesive from the viewpoint that the drying time is short and the workability is good, and the adhesive is performed regardless of the material of the sheet.

Examples of the hot-melt adhesive include rubber-based hot-melt adhesives based on styrene-based elastomers and olefin-based hot-melt adhesives based on amorphous polyalphaolefin (APAO). .
Examples of the styrene elastomer include styrene / butadiene rubber (SBR), styrene / butadiene / styrene block copolymer (SBS), styrene / isoprene / styrene block copolymer (SIS), styrene / ethylene / butylene / styrene block copolymer. Examples thereof include a polymer (SEBS) and a styrene / ethylene / propylene / styrene block copolymer (SEPS).

The coating amount of the adhesive 3 is appropriately set according to the type, material, combination, type of adhesive, and the like of each sheet. Coating application amount, the adhesive strength, softness, texture, considering exudation, 0.5 to 5.0 g / m ^2, particularly preferably a 0.5 to 2.5 g / m ^2. The adhesive 3 is preferably applied to all the convex portions, but may not be partially applied as long as the effect of the present invention is not affected.

The third sheet 5 is preferably a moisture permeable sheet. Although the material of the 3rd sheet | seat 5 is suitably set according to a use and the objective, it is preferable to use the porous sheet | seat which has moisture permeability and has leak-proof property. The moisture permeability of the porous sheet is appropriately set according to the application and purpose. When the composite sheet is used as an outer layer material of an absorbent article, the moisture permeability is sufficient to release moisture to suppress stuffiness and fogging, and to leak moisture and moisture to the outside and wet clothes, etc. In view of having sufficient water resistance, it is preferably 0.5 to 4.0 g / (100 cm ² · h), more preferably 1.0 to 3.0 g / (100 cm ² · h). Furthermore, regarding leakage prevention, when used as an outer layer material of an absorbent article, moisture and moisture are not leaked outside and do not wet clothes, so that the water pressure resistance is 9.8 kPa or more, particularly 19.6 kPa. The above is preferable.

  Examples of the porous sheet used for the third sheet 5 include a liquid obtained by melt-kneading a hydrophobic thermoplastic resin and a filler to form a sheet, and uniaxially or biaxially stretching the sheet. Examples thereof include a sheet having impermeableness and moisture permeability. Examples of the thermoplastic resin include polyolefin. Examples of the polyolefin include high to low density polyethylene, linear low density polyethylene, polypropylene, polybutene and the like, and these can be used alone or in combination. Examples of the filler include a fine inorganic filler made of calcium carbonate or the like, or an organic polymer incompatible with the thermoplastic resin.

  The thickness of the third sheet 5 is 10 to 50 μm, particularly 10 to 30 μm from the viewpoint of giving a good texture and flexibility, having sufficient strength in use, and realizing it at an economical cost. It is preferable to do.

  The joining method of the said 2nd sheet | seat 4 and the said 3rd sheet | seat 5 is suitably set according to the material of these sheets, the softness required for a use, adhesive strength, a processing speed, etc. Examples of the bonding method include a bonding method using an adhesive, a method using thermal bonding, and a method using ultrasonic bonding. The adhesive used for joining the second sheet 4 and the third sheet 5 includes a rubber-based hot-melt adhesive based on a styrene elastomer and an olefin based on amorphous polyalphaolefin (APAO). And hot melt adhesives.

  Next, the manufacturing method of the composite sheet of this invention is demonstrated based on the preferable embodiment.

  FIG. 4 schematically shows an apparatus for manufacturing the composite sheet 1. As shown in FIG. 4, the manufacturing apparatus 10 includes a punching unit 11, a stretching unit 12, an adhesive coating unit 13, a joining unit 14, and a winding unit 15.

  The perforating means 11 includes a pair of rolls 111 and 112. The roll 111 is provided with a blade corresponding to the hole 21 in the peripheral surface portion. In the case of using the original sheet of the first sheet 2 provided with the holes 21 in advance, the punching means 11 is not necessary.

  The stretching means 12 includes a pair of two stretching rolls 121 and 122. In the stretching means 12, the speed of the downstream second stretching roll 122 is set to be higher than the speed of the upstream first stretching roll 121, and a predetermined tension is applied to the first sheet 2 by this speed difference.

The adhesive coating means 13 is preferably a die coater type coating apparatus. The die coater type coating apparatus has a head portion (gun head) 131 brought into contact with the convex portion on one side of the first sheet 2, and the adhesive 3 discharged from the discharge port formed in the head portion 131 Apply directly to one sheet 2. The head portion 131 has a flat end substantially parallel to the base material sheet 20 at the front end portion positioned downstream of the discharge port in the flow direction of the base material sheet 20.
The reason why this die coater is particularly preferable is that the coating is performed while the head portion is in contact with the sheet, so that the adhesive is applied only to the portion in contact with the head portion, that is, only the convex portion. Thereby, the 1st sheet | seat 2 and the 2nd sheet | seat 4 are joined partially by the said convex-shaped part, and the solid shape of a standing part is not crushed. Further, by being partially joined, the softness is excellent. Furthermore, since the adhesive is not applied to the opening portion, the adhesive oozes out on the side of the first sheet opposite to the joint portion 22 with the second sheet, causing blocking or stickiness to the product. The tactile sensation is not given.

  The joining means 14 includes a pair of rolls 141 and 142, and sandwiches the first sheet 2 coated with the adhesive 3 together with the second sheet 4 and the third sheet 5 merged in the flow. Join.

  The winding means 15 includes a reel 151 that rotates at a predetermined rotational speed, and winds the composite sheet 1 around the reel 151 in a roll shape.

  In manufacturing the composite sheet 1 by the manufacturing apparatus 10, first, the base sheet 20 of the first sheet 2 is fed out from the raw roll 200 and continuously supplied to the punching machine 11. That is, the base sheet 20 is continuously supplied from the original roll 200 to a composite sheet production line using an original supply mechanism (not shown) having a known feeding mechanism. A large number of the holes 21 are arranged in a staggered arrangement through the base sheet 20 between the pair of rolls 111 and 112.

  Next, the first sheet 2 provided with a large number of holes 21 is supplied to the stretching machine 12. Then, a tension is applied to the first sheet 2 in which a large number of downstream holes 21 are arranged in a staggered arrangement in the length direction of the sheet so that the holes 21 are widened, and the peripheral portions of the holes 21 are undulated to form a convex shape. Forming part.

  The tension applied to the first sheet 2 is set according to the material of the first sheet 2 and the form, arrangement, and dimensions of the holes 21 arranged in the first sheet 2. The tension is 0.5 to 10 N / 50 mm, particularly 0.75 to 5 N / 50 mm, taking into account the ease of forming a fold-like or pile-like standing portion, the sheet breakage at the time of stretch opening, and the stretch opening property. It is preferable that

Further, the stretching ratio in the direction in which the tension of the first sheet 2 is applied when the tension is applied depends on the purpose, purpose, material of the first sheet 2, and the form of the holes 21 disposed in the first sheet 2. It is set according to the arrangement and dimensions. The stretching ratio is preferably 1 to 100%, particularly preferably 5 to 50%, taking into account the ease of forming a fold-like or pile-like standing portion, the sheet breakage during stretch opening, and the stretch opening property. . Here, the stretching ratio is, for example, the roll of the pair two pairs of stretching machine 12, the speed ratio [(V ₁₂₂ / V peripheral speed V ₁₂₂ of the peripheral velocity V ₁₂₁ in the first draw roll 121 the second stretching roll 122 _121-1 ) × 100].

  Next, the first sheet 2 is supplied to the adhesive coating means 13. Then, the adhesive 3 is applied to the convex portion formed on one side of the first sheet 2 by the adhesive application means 13.

  Next, the second sheet 4 and the third sheet 5 in which an adhesive is applied in advance to the joining surface are joined to the composite sheet production line. Then, the first to third sheets are overlapped and passed between the rolls 141 and 142 of the joining means 14, and the first sheet 2 and the second sheet 4 are joined via the adhesive 3. It is set as the continuous sheet | seat of the composite sheet 1 with which the 3rd sheet | seat 5 was joined via the said adhesive agent to the side where the 1st sheet | seat 2 is not joined.

  The obtained continuous sheet of the composite sheet 1 is supplied to the winding means 15 and wound on the outer periphery of the reel 151.

  The composite sheet 1 manufactured in this way is flexible and excellent in texture. In addition, the configuration is simple, and it can be efficiently produced with high productivity and low cost as in the above-described manufacturing method.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not restricted to the above-mentioned embodiment, In the range which does not deviate from the meaning of this invention, it can change suitably.

  For example, in the embodiment, the composite sheet 1 has the three-layer structure of the first to third sheets. However, the composite sheet 1 may be only the first and second sheets, and is further separated into the third sheet. These sheets can be joined to form a four-layer structure or more.

  Moreover, in the manufacturing method of the said embodiment, although the continuous sheet of the composite sheet 1 was wound up in roll shape, it can also cut | disconnect by a cutting means for every predetermined length, without winding up in roll shape. In addition, the second sheet 4 and the third sheet 5 are joined to the first sheet 2 and joined. However, after the second sheet 4 and the third sheet 5 are joined in advance, the first sheet 2 is joined. Can be joined together.

  The use of the composite sheet of the present invention is not particularly limited, but various uses can be mentioned by taking advantage of its texture. Examples thereof include absorbent article members such as disposable diapers and sanitary napkins, various wiping sheets, and cleaning sheets. In particular, by using it as an outer layer material of an absorbent article, an absorbent article having a soft and soft touch like a towel can be obtained. Moreover, the formed hole can give the effect and impression of an absorbent article excellent in air permeability.

  Hereinafter, the present invention will be described more specifically with reference to examples.

  Using the sheets shown in Table 1, composite sheets were produced as in the following examples, and various properties of the obtained composite sheets were evaluated as follows. The results are shown in Table 1.

[Example 1]
A composite sheet having the sheet configuration shown in Table 1 was prepared as follows. And the sheet | seat physical property of the obtained composite sheet was evaluated as follows. The results are shown in Table 1.

<Constituent material of composite sheet>
First sheet: an air-through nonwoven fabric having a core / sheath structure of polyester / polyethylene and 100% fiber having a fiber diameter of 2.0 dtex and a basis weight of 20 g / m ² .
Form of the holes in the first sheet, etc .: Hole length L1: 3 mm; Hole interval L2 in a row: 1 mm
Distance L3 between rows: 2 mm; length L4: 1 mm that overlaps when adjacent holes 21 are projected in the row direction; angle θ between the length direction of the holes and the row direction: 0 degree (parallel)
Second sheet: Non-woven fabric of SMS (spun bond / melt blown / spun bond) with a basis weight of 15 g / m ² and a resin whose main material is a propylene-ethylene random copolymer Hot melt adhesive: Olefin hot melt, FT1069 (manufactured by Nippon Fuller)

<Production of composite sheet>
After feeding out the first sheet and forming a slit-like hole with the shape and arrangement of the hole by a rotary die cutter, it is sent to a stretching device composed of a pair of two rolls and stretched at a stretch rate of 30%. went. At this time, the speed of the first stretching roll was 7.7 m / min, and the speed of the second stretching roll was 10 m / min. The angle formed between the row direction of the holes and the direction in which tension is applied was approximately 90 degrees. The first sheet was supplied to the adhesive coating means while maintaining this stretched state. The hot melt was applied while a die head was brought into contact with the first sheet by a die coater method. The adhesive application temperature was 150 ° C., and the adhesive application amount was 2.0 g / m ² . Then, the 1st sheet | seat with which this adhesive agent was coated and the 2nd sheet | seat drawn | fed out were joined and joined to a pair of roll, and the composite sheet was obtained.

[Example 2]
Using the following first sheet, second sheet and third sheet, a composite sheet was prepared as follows. And the sheet | seat physical property of the obtained composite sheet was evaluated as follows. The results are shown in Table 1.

<Constituent material of composite sheet>
First sheet: air / through nonwoven fabric having a core / sheath structure of polyester / polyethylene and a fiber diameter of 2.0 dtex and having a fiber diameter of 2.0 dtex and a basis weight of 20 g / m ^2. the second sheet: fiber material is a basis weight of 10 g / m ² polypropylene SMS (Supanbondo / Merutofu Bu loans /
Spunbond) Nonwoven fabric Third sheet: Porous sheet Third sheet composition: Linear low density polyethylene (Ultzex UZ2520F, manufactured by Mitsui Chemicals, density 0.925 g / cm ³ , melt index 2.0 g / 10 min) 38% by weight , Calcium carbonate (Escalon # 2000, Sankyo Seimitsu Co., Ltd., average particle size 1 μm) 57% by weight, stearic acid / acidic acid / trimethylol chloroform polycondensate (feed theory molar ratio 4/1/2, saponification) 240, acid value 1.5, hydroxyl value 9.9) 4% by weight, stearic acid (Lunac S-40, manufactured by Kao Corporation) 1% by weight
Third sheet molding method: The above composition is kneaded with a twin screw kneader to produce pellets. The obtained pellets are supplied to an inflation molding machine to form a 35 μm thick sheet. The obtained sheet is stretched at a stretching temperature of 50 ° C. and a stretching ratio of 2.3 times using a roll stretching machine to obtain a porous sheet.
Physical property of the third sheet: basis weight 20 g / m ² ; thickness 0.02 mm; moisture permeability 2.0 g / 100 cm ² · h
Hot melt: Olefin hot melt, FT1069 (Nippon Fuller)

<Production of composite sheet>
The first sheet was fed out, and slit-shaped holes were formed with the shape and arrangement of the holes by a rotary die cutter. Next, it sent to the extending | stretching apparatus comprised by the pair of 1 pair of rolls, and extended | stretched with the elongation rate of 30%. At this time, the speed of the first stretching roll was 7.7 m / min, and the speed of the second stretching roll was 10 m / min. The first sheet was supplied to the adhesive coating means while maintaining this stretched state. And the said hot melt was apply | coated, making a die head contact the 1st sheet | seat by the die-coater method. The hot melt coating temperature was 150 ° C., and the hot melt coating amount was 2.0 g / m ² . Subsequently, the first sheet coated with the hot melt and the second sheet fed out were joined to a pair of rolls and joined. Further, using the same adhesive coating means and die coater, the hot melt was applied to the surface of the second sheet where the first sheet was not joined. The hot melt coating temperature was 150 ° C., and the hot melt coating amount was 1.2 g / m ² . Then
The joined first sheet and second sheet and the third sheet fed out were joined to a pair of rolls to obtain a composite sheet.

<Evaluation of composite sheet>
(1) Basis weight: to prepare a sample 10 cm × 10 cm to measure the weight W _T.
Basis weight (g / m ² ) = W _T /0.01
(2) Thickness: Measured according to the measurement method described in paragraph [0016].
(3) Buckling strength: Measured according to the measurement method described in paragraph [0018].
(4) Compression stiffness: Measured according to the measurement method described in paragraph [0020].
(5) Roughness: Measured according to the measurement method described in paragraph [0023] above.
(6) Moisture permeability: Measured according to the measurement method described in paragraph [0026] above.

  As shown in Table 1, the obtained composite sheet was small in buckling strength and compression stiffness, large in thickness, soft and fluffy, and soft and excellent in texture.

  The use of the composite sheet of the present invention is not particularly limited, but various uses can be mentioned by taking advantage of its texture. Examples thereof include absorbent article members such as disposable diapers and sanitary napkins, various wiping sheets, and cleaning sheets.

It is the perspective view which fractured | ruptured the part which shows typically the composite sheet which concerns on one Embodiment of this invention. It is an expanded sectional view showing typically the section of the composite sheet concerning the embodiment. It is an enlarged plan view which shows typically the 1st sheet | seat which concerns on the said embodiment. It is a figure which shows typically the manufacturing process of the composite sheet which concerns on the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite sheet 2 1st sheet 22 Joining part 23 Standing part 3 Adhesive 4 Second sheet 5 3rd sheet

Claims (8)

A first sheet provided with a large number of holes, and a second sheet bonded to the first sheet via an adhesive,
The composite sheet is provided with a undulation having a joint portion with the second sheet and an upright portion that stands up without being joined to the second sheet in a peripheral portion of each hole of the first sheet. ,
The composite sheet, wherein the first sheet is an air-through nonwoven fabric and the second sheet is a nonwoven fabric containing spunbond.   The composite sheet according to claim 1, wherein the nonwoven fabric used for the second sheet is a nonwoven fabric in which a spunbond and a meltblown are combined.   The composite sheet according to claim 1 or 2, wherein the plurality of holes are arranged in a staggered arrangement.   The composite sheet according to any one of claims 1 to 3, wherein the holes are arranged so as to overlap each other when the adjacent holes are projected in a direction perpendicular to their length direction.   The composite sheet according to any one of claims 1 to 4, wherein the holes arranged in the first sheet are aligned in a direction substantially orthogonal to a direction in which the tension is applied.   The composite sheet according to claim 1, wherein the holes are provided in a slit shape.   The composite sheet according to any one of claims 1 to 6, wherein a third sheet having moisture permeability is bonded to a surface of the second sheet that is not bonded to the first sheet. A plurality of holes are formed in an air-through nonwoven fabric to form a first sheet, and the peripheral portion of the holes is undulated by applying tension to the first sheet so that the holes expand, and then the undulation of the peripheral portion An adhesive is applied to a convex portion on one side of the first sheet formed along with the first sheet, and the first sheet and a second sheet made of a nonwoven fabric containing spunbond are joined via the adhesive. A method for producing a composite sheet.

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