阅读说明：本技术 伸缩性层叠体及其制造方法 (Stretchable laminate and method for producing same ) 是由 内田翔 中川宗重 生岛伸祐 于 2020-04-24 设计创作，主要内容包括：本发明要解决的问题为,提供兼顾优异的伸长率和断裂强度的伸缩性层叠体及其制造方法。本发明的伸缩性层叠体(100)具备无纺布层(20a、20b)和弹性体层(10)。该无纺布层(20a、20b)为长纤维水力缠结无纺布。通过使用长纤维水力缠结无纺布,可得到兼顾优异的伸长率和断裂强度的伸缩性层叠体,所述长纤维水力缠结无纺布是通过利用水力缠结法使通过纺丝成网法形成的纤维固着而形成的无纺布。(The problem to be solved by the present invention is to provide a stretchable laminate having both excellent elongation and excellent breaking strength, and a method for producing the same. The stretchable laminate (100) comprises nonwoven fabric layers (20a, 20b) and an elastomer layer (10). The nonwoven fabric layers (20a, 20b) are long fiber hydroentangled nonwoven fabrics. By using a filament hydroentangled nonwoven fabric formed by fixing fibers formed by a spunlaid process by a hydroentanglement method, a stretchable laminate having both excellent elongation and breaking strength can be obtained.)

1. A stretchable laminate comprising a nonwoven fabric layer and an elastomer layer,

the non-woven fabric layer is a long fiber hydroentangled non-woven fabric.

2. The stretchable laminate according to claim 1, wherein the long fiber hydroentangled nonwoven fabric has a basis weight of 25gsm or less.

3. The stretchable laminate according to claim 1 or 2, wherein the long fiber hydroentangled nonwoven fabric has an elongation at 5N of 50% or more.

4. A stretchable laminate according to any one of claims 1 to 3, wherein the long fiber hydroentangled nonwoven fabric has a breaking strength of 10N or more.

5. A stretchable laminate according to any one of claims 1 to 4, wherein the long fiber hydroentangled nonwoven fabric has a breaking strength of 15N or more.

6. A stretchable laminate according to any one of claims 1 to 5, wherein the long fiber hydroentangled nonwoven fabric is an activated nonwoven fabric.

7. A stretchable laminate according to any one of claims 1 to 6, wherein the long fiber hydroentangled nonwoven fabric is a nonwoven fabric shrunk in the 1 st direction.

8. A stretchable laminate according to any one of claims 1 to 7, wherein the elastomer layer has an intermediate layer and surface layers disposed on both sides of the intermediate layer.

9. A stretchable laminate according to any one of claims 1 to 8, wherein the elastomer layer has a thickness of 20 to 200 μm.

10. The stretchable laminate according to claim 8 or 9, wherein the surface layer comprises an olefin-based elastomer.

11. The stretchable laminate according to any one of claims 8 to 10, wherein the intermediate layer comprises an olefin-based elastomer or a styrene-based elastomer.

12. A stretchable laminate according to any one of claims 1 to 11, wherein the elastomer layer is an activated elastomer layer.

13. A stretchable laminate according to any one of claims 1 to 12, wherein the nonwoven fabric layer and the elastomer layer are ultrasonically welded and bonded.

14. An article comprising the stretchable laminate according to any one of claims 1 to 13.

15. A method for producing a stretchable laminate comprising a nonwoven fabric layer and an elastomer layer, said method comprising:

activating the long fiber hydroentangled nonwoven fabric; and

the activated nonwoven fabric and the elastomer layer are joined by at least 1 joining method selected from the group consisting of ultrasonic welding and attachment by means of an adhesive layer.

16. The method for producing a stretchable laminate according to claim 15, wherein the activation of the long fiber hydroentangled nonwoven fabric and the joining of the activated nonwoven fabric to the elastomer layer are performed continuously in-line.

17. The method for producing a stretchable laminate according to claim 15 or 16, further comprising activating the bonded nonwoven fabric and elastomer layer.

18. The method for producing a stretchable laminate according to any one of claims 15 to 17, further comprising shrinking the long fiber hydroentangled nonwoven fabric in the 1 st direction.

Technical Field

The present invention relates to a stretchable laminate and a method for producing the same.

Background

As a member of an article such as a sanitary product such as a diaper and a mask, various stretchable laminates have been proposed (for example, see patent documents 1 and 2). As such a member, a stretchable laminate formed of 2 or more layers including an elastomer layer has been proposed. Typically, a stretchable laminate having a nonwoven fabric layer on at least one side of an elastomer layer has been proposed. However, the nonwoven fabric layer may not have sufficient elongation and may not have desired stretchability. As a method for improving the elongation of the nonwoven fabric, it is known to subject the nonwoven fabric to an activation treatment (pre-activation) in advance before the production of the stretchable laminate. However, depending on the nonwoven fabric, the nonwoven fabric may be broken by preactivation or may be perforated in the plane of the nonwoven fabric, and thus desired performance may not be obtained.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2012-187857

Patent document 2: japanese patent No. 3830818

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above-described conventional problems, and an object thereof is to provide a stretchable laminate having both excellent elongation and excellent breaking strength, and a method for producing the same.

Means for solving the problems

The stretchable laminate of the present invention comprises a nonwoven fabric layer and an elastomer layer. The nonwoven layer is a long-fiber hydroentangled non-woven fabric (long-fiber hydroentangled non-woven fabric).

In 1 embodiment, the basis weight of the filament hydroentangled nonwoven fabric is 25gsm or less.

In 1 embodiment, the long fiber hydroentangled nonwoven fabric has an elongation at 5N of 50% or more.

In 1 embodiment, the long fiber hydroentangled nonwoven fabric has a breaking strength of 10N or more.

In 1 embodiment, the long fiber hydroentangled nonwoven fabric has a breaking strength of 15N or more.

In 1 embodiment, the nonwoven fabric is an activated long fiber hydroentangled nonwoven fabric.

In 1 embodiment, the filament hydroentangled nonwoven fabric is a nonwoven fabric that has been contracted in the 1 st direction.

In 1 embodiment, the elastomer layer includes an intermediate layer and surface layers disposed on both sides of the intermediate layer.

In 1 embodiment, the thickness of the elastomer layer is 20 μm to 200 μm.

In 1 embodiment, the surface layer includes an olefin elastomer.

In 1 embodiment, the intermediate layer contains an olefin elastomer or a styrene elastomer.

In 1 embodiment, the elastomer layer is an activated elastomer layer.

In 1 embodiment, the nonwoven fabric layer and the elastomer layer are joined by ultrasonic welding.

Another aspect of the invention provides an article. The article comprises the stretchable laminate.

Another aspect of the present invention provides a method for producing a stretchable laminate. The method for producing a stretchable laminate comprising a nonwoven fabric layer and an elastomer layer, the method comprising: activating the long fiber hydroentangled nonwoven fabric; and joining the activated nonwoven fabric and the elastomer layer by at least 1 joining method selected from the group consisting of ultrasonic welding and attachment by means of an adhesive layer.

In 1 embodiment, activation of the long fiber hydroentangled nonwoven fabric and joining of the activated nonwoven fabric and the elastomeric layer are performed continuously in-line.

In 1 embodiment, the method further comprises activating the bonded nonwoven fabric and elastomer layer.

In one embodiment, the method further comprises shrinking the long fiber hydroentangled nonwoven fabric in the 1 st direction.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a stretchable laminate having both excellent elongation and excellent breaking strength can be obtained. The stretchable laminate of the present invention comprises a nonwoven fabric layer and an elastomer layer. The non-woven fabric layer is a long fiber hydroentangled non-woven fabric. By using the filament hydroentangled nonwoven fabric as the nonwoven fabric layer, excellent elongation and breaking strength can be achieved at the same time. Further, the long fiber hydroentangled nonwoven fabric can be produced at low cost. Therefore, a stretchable laminate excellent in elongation and breaking strength can be produced at low cost. In addition, poor appearance due to holes and the like can be prevented.

Drawings

Fig. 1 is a schematic cross-sectional view of a stretchable laminate according to 1 embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view of a stretchable laminate according to another embodiment of the present invention.

Fig. 3A is a schematic perspective view of a ring roller (ringroll) used in 1 embodiment of the present invention.

Fig. 3B is a schematic enlarged view of the engagement portion of the ring roller shown in fig. 3A.

Detailed Description

A. Outline of stretchable laminate

The stretchable laminate of the present invention comprises a nonwoven fabric layer and an elastomer layer. The non-woven fabric layer is a long fiber hydroentangled non-woven fabric. Fig. 1 is a schematic cross-sectional view of a stretchable laminate according to 1 embodiment of the present invention. In the illustrated example, the stretchable laminate 100 includes a nonwoven fabric layer 20 and an elastomer layer 10. In this embodiment, the stretchable laminate 100 includes the nonwoven fabric layer 20 only on one side of the elastomer layer 10.

Fig. 2 is a schematic cross-sectional view of a stretchable laminate according to another embodiment of the present invention. In the illustrated example, the stretchable laminate 100 includes: an elastomer layer 10, and nonwoven layers 20a, 20 b. In this embodiment, the stretchable laminate 100 includes nonwoven fabric layers 20a and 20b on both surfaces of the elastomer layer 10. The nonwoven fabric layers 20a and 20b may be formed of the same nonwoven fabric, or may be formed of different nonwoven fabrics. In addition, the nonwoven fabric layer and the elastomer layer may contain any other suitable layer.

In 1 embodiment, the stretchable laminated body may have a through-hole. By having the through-holes, more excellent air permeability can be exhibited. A stretchable laminate having through-holes is disclosed in, for example, japanese patent application laid-open No. 2016-203618. The disclosure is incorporated into this specification by reference.

The thickness of the stretchable laminate may be set to any appropriate value. The thickness of the stretchable laminate is preferably 0.1mm or more, more preferably 0.15mm or more, and still more preferably 0.2mm or more. The thickness of the stretchable laminate is preferably 1.0mm or less, more preferably 0.8mm or less, still more preferably 0.6mm or less, particularly preferably 0.5mm or less, and most preferably 0.45mm or less. By setting the thickness to the above range, the sheet can be easily used as a member for articles such as sanitary goods including diapers and masks.

B. Non-woven fabric layer

As the nonwoven fabric layer, a long fiber hydroentangled nonwoven fabric was used. By using the filament hydroentangled nonwoven fabric, a stretchable laminate having both excellent elongation and breaking strength can be obtained. Nonwoven fabrics can be generally classified according to the method of forming the web and the method of fixing the web. In the present specification, the long fiber hydroentangled nonwoven fabric refers to a nonwoven fabric formed by fixing a web made of fibers formed by a spunlaid method (spunlaid method) by a hydroentangling method (hydroentangling method). The long fiber hydroentangled nonwoven fabric is excellent in breaking strength. Therefore, the breaking strength of the stretchable laminate can be improved. Further, the elongation may be improved by the activation treatment described later. By using such a nonwoven fabric as the nonwoven fabric layer, the stretchable laminate obtained can achieve both excellent elongation and breaking strength.

As described above, the long fiber hydroentangled nonwoven fabric is produced by a production method including: the method includes the steps of producing a web by a spunlaid method and jetting a water stream to the web to entangle fibers contained in the web with each other (fixation by hydroentanglement). The web used in the long fiber hydroentangled nonwoven fabric may be formed by any suitable method. For example, a resin as a raw material of a fiber is melted and fluidized, and is ejected from an arbitrary appropriate spinning nozzle to be cooled and solidified, thereby being spun to form a web (melt spinning). Alternatively, the resin dissolved in the solvent may be discharged from the spinning nozzle, and the solvent may be removed to spin (wet spinning). The formation may be carried out using an apparatus used for a nonwoven fabric (for example, a spunbonded nonwoven fabric) by a spunlaid method.

Next, a web made of fibers formed by the spunlaid process may be entangled with a water stream to form a long fiber hydroentangled nonwoven fabric. Specifically, a high-pressure water jet (high-pressure water flow jet) may be jetted to the web to entangle the fibers with each other, thereby obtaining a long fiber hydroentangled nonwoven fabric. The injection by the high-pressure water jet may be performed by 1 high-pressure water jet, or may be performed by combining 2 or more high-pressure water jets. When 2 or more high-pressure water jets are used, the jets may be performed under the same condition or may be performed under different conditions. Alternatively, the high pressure water jets may be directed at the web at any suitable angle. For example, the high-pressure water jet may be ejected from a vertical direction with respect to the conveying direction of the web, or may be ejected from an oblique direction (for example, 45 degrees with respect to the conveying direction). When 2 or more high-pressure water jets are used, the jets may be performed from the same angle or from different angles. Further, the web may be sprayed on both surfaces, or may be sprayed on only one surface.

As the fibers constituting the nonwoven fabric layer, any suitable fibers are used. For example, there may be mentioned fibers of polyolefin such as polypropylene, polyethylene, polyester, polyamide, polyurethane, elastomer, rayon, cellulose, acryl, copolymer thereof, blend thereof (blend), or mixture thereof. Among these, fibers containing polyolefins such as polypropylene and polyethylene are preferable in that the effects of the present invention can be further exhibited.

The nonwoven fabric constituting the nonwoven fabric layer may contain fibers as a uniform structure, or may contain a two-component structure such as a sheath/core type, a side by side structure, a sea-island structure, or another two-component structure. For a detailed description of Nonwoven Fabrics, Reference may be made to "Nonwoven Fabric Primer and Reference Sampler", E.A. Vaughn, Association of the Nonwoven Fabrics Industry, 3 rd edition (1992).

The fibers constituting the nonwoven fabric may contain any other suitable component within a range not impairing the effect of the present invention. Examples of such other components include other polymers, tackifiers, plasticizers, anti-deterioration agents, pigments, dyes, antioxidants, antistatic agents, lubricants, foaming agents, thermal stabilizers, light stabilizers, inorganic fillers, and organic fillers. These may be 1 kind only or 2 or more kinds. The content ratio of the other component is preferably 10% by weight or less, more preferably 7% by weight or less, further preferably 5% by weight or less, particularly preferably 2% by weight or less, and most preferably 1% by weight or less.

The basis weight of the long fiber hydroentangled nonwoven is preferably 25gsm (g/m)²) The lower limit is more preferably 23gsm or lower, and still more preferably 20gsm or lower. The basis weight of the long fiber hydroentangled nonwoven fabric is preferably 13gsm or more. The basis weight of the nonwoven fabric can be measured by any suitable method. For example, the measurement can be performed by the following method. The non-woven fabric can be cut into 100cm by an electronic balance²The weight of the obtained sample was measured and converted to g/m²Unit (gsm), from which basis weight of the nonwoven was determined. The basis weight of the nonwoven fabric in the stretchable laminate in which the nonwoven fabric layer and the elastomer layer are directly laminated may be obtained by subtracting the basis weight of the stretchable laminate measured by the same method as the method for measuring the nonwoven fabric described above from the basis weight of the stretchable laminate measured by the electron microscopeThe basis weight of the elastomer layer estimated by the cross-sectional observation was calculated. In the case of a stretchable laminate having nonwoven fabrics on both sides, the basis weight of each nonwoven fabric can be calculated by division based on the thickness ratio of each nonwoven fabric. Further, in the case of a stretchable laminate in which a nonwoven fabric layer and an elastomer layer are laminated with a binder, the nonwoven fabric layer and the elastomer layer are separated from each other with a solvent, the binder is removed from the nonwoven fabric layer, and the basis weight of the nonwoven fabric can be measured using the obtained nonwoven fabric. In the nonwoven fabric shrunk in the 1 st direction, the fibers become dense and the basis weight becomes large. The basis weight of the nonwoven fabric before shrinking may be in the above range for the nonwoven fabric shrunk in the 1 st direction.

In embodiment 1, the basis weight of the nonwoven fabric shrunk in the 1 st direction is preferably 40gsm or less, more preferably 35gsm or less, further preferably 30gsm or less, and most preferably 25gsm or less. The basis weight of the nonwoven fabric shrunk in the 1 st direction is preferably 10gsm or more, more preferably 13gsm or more, and further preferably 15gsm or more.

The long fiber hydroentangled nonwoven fabric preferably has an elongation of 50% or more at 5N and a breaking strength of 10N or more. The elongation at 5N of the long fiber hydroentangled nonwoven fabric is more preferably 100% or more, and still more preferably 120% or more. The breaking strength of the long fiber hydroentangled nonwoven fabric is more preferably 15N or more, and still more preferably 20N or more. By setting the elongation and breaking strength at 5N to the above ranges, a stretchable laminate having excellent elongation and breaking strength can be obtained.

The long fiber hydroentangled nonwoven fabric is preferably activated (pre-activation treatment). By activating the nonwoven fabric, the elongation of the nonwoven fabric is further improved. Further, the elongation of the nonwoven fabric (which is not easily elongated) having a room for improvement in elongation by activation can be improved. Further, by using a non-extensible nonwoven fabric, a nonwoven fabric layer having an activated portion that is easily extensible and an inactivated portion that is not easily extensible can be produced. By having an inactive portion that is not easily elongated, the holding force when the member is stretched and attached to another member can be improved. In the case where the stretchable laminate of the present invention has nonwoven fabric layers on both sides of the elastomer layer, a nonwoven fabric having both surfaces activated may be used, or a nonwoven fabric having only one surface activated may be used.

The activation treatment may be performed by any suitable method. The activation treatment can be performed, for example, by a stretching treatment in which the long fibers are hydroentangled in the nonwoven fabric in the width direction and a treatment in which the fiber structure of a part of the nonwoven fabric is mechanically destroyed. By performing the activation treatment, stretching can be performed with a smaller force. The activation treatment may be partially performed or may be entirely performed. In addition, the activation treatment may be performed plural times. When the activation treatment is performed a plurality of times, the same activation treatment may be performed, or different activation treatments may be combined.

The activation by the mechanical destruction treatment can be performed, for example, by conveying the long fiber hydroentangled nonwoven fabric while holding the nonwoven fabric with 2 rolls (e.g., ring rolls) having unevenness. Fig. 3A is a schematic perspective view of a ring roller used in 1 embodiment of the present invention, and fig. 3B is a schematic enlarged view of an engagement portion of the ring roller shown in fig. 3A. The nonwoven fabric is transported between the 1 st ring roller 201 and the 2 nd ring roller 202 and subjected to an activation treatment. The 1 st ring roller 201 includes a plurality of protrusions 211 and grooves 221. Similarly, the 2 nd ring roller 202 includes a plurality of protrusions 212 and grooves 222. The ring rollers are arranged so that the protrusions 211 and the grooves 222 of the 1 st and 2 nd ring rollers engage with the protrusions 212 and the grooves 221 of the 2 nd and 1 st ring rollers, respectively. While being conveyed between the 1 st ring roller 201 and the 2 nd ring roller 202, both surfaces of the nonwoven fabric are activated at an arbitrary depth by the protrusions 211, 212. In the ring roller, the radius of the tip of the protrusion (R in fig. 3B) and the pitch width (D in fig. 3B) are set to any appropriate values. For example, a ring roller having a tip radius R of 1mm and a pitch width D of 7mm may be used in combination. When the roll is in contact with the filament hydroentangled nonwoven fabric, it is preferable to bring the roll into contact with the filament hydroentangled nonwoven fabric to any suitable depth. The depth at the time of contact may be set in accordance with the type of fibers constituting the nonwoven fabric, the basis weight, and the like so that the long fibers are hydroentangled into the nonwoven fabric to have a preferable elongation (for example, an elongation at 5N is 50% or more). The depth at the time of the deepest treatment is preferably 2mm to 12mm, more preferably 4mm to 10mm, and further preferably 6mm to 8 mm.

In 1 embodiment, the long fiber hydroentangled nonwoven fabric is a nonwoven fabric that has been shrunk in the 1 st direction. The nonwoven fabric shrunk in the 1 st direction has fibers constituting the nonwoven fabric becoming dense due to shrinkage. When the laminate is used, the nonwoven fabric (and consequently the stretchable laminate) stretches from the portion where the fibers are dense. Therefore, a stretchable laminate which can be more easily stretched and has excellent stretchability can be obtained. In the present specification, the 1 st direction means any 1 direction selected on the plane of the nonwoven fabric. In 1 embodiment, the 1 st direction is the CD direction (width direction) of the nonwoven fabric. In 1 embodiment, the 1 st direction is the same direction as the direction in which the stretch laminate is stretched when used. By shrinking in the 1 st direction, the stretchability of the long fiber hydroentangled nonwoven fabric in the 1 st direction can be improved.

The shrinkage in the 1 st direction may be performed so as to have any suitable shrinkage ratio. For example, the shrinkage rate of the filament hydroentangled nonwoven fabric in the 1 st direction is, for example, 20% or more, preferably 30% or more, more preferably 40% or more, and most preferably 50% or more. By setting the shrinkage rate to the above range, a stretchable laminate having more excellent elongation can be obtained. The shrinkage rate is, for example, 100% or less, preferably 80% or less, and more preferably 60% or less. In the present specification, the shrinkage ratio is a value calculated from the ratio of the length of the shrunk nonwoven fabric in the 1 st direction to the length of the nonwoven fabric in the 1 st direction (for example, the width direction) of the blank (i.e., before shrinking) (the length of the nonwoven fabric in the 1 st direction after shrinking/the length of the nonwoven fabric blank in the 1 st direction × 100).

When the filament hydroentangled nonwoven fabric and the other nonwoven fabric are used in combination, any suitable nonwoven fabric may be used as the other nonwoven fabric. A nonwoven fabric having excellent flexibility is preferably used. Specific examples thereof include carded nonwoven fabrics, spunlace non-woven fabrics, air-through nonwoven fabrics, meltblown nonwoven fabrics, spunbonded nonwoven fabrics, and spunmelt nonwoven fabrics. These nonwoven fabrics may be used as they are, or may be subjected to the above-mentioned activation treatment and/or contraction treatment in the 1 st direction.

C. Elastomeric layer

The elastomeric layer may be formed using any suitable elastomeric resin. Examples of the elastomer resin as the main component of the elastomer layer include olefin elastomers, styrene elastomers, vinyl chloride elastomers, urethane elastomers, ester elastomers, and amide elastomers. Preferably, an olefin elastomer or a styrene elastomer is used.

By using the olefin elastomer, thermal deterioration during film formation can be suppressed. In addition, the storage stability is improved, and the variation of the physical property value during storage can be suppressed. Examples of the olefin-based elastomer include olefin block copolymers, olefin random copolymers, ethylene copolymers, propylene copolymers, ethylene olefin block copolymers, propylene olefin block copolymers, ethylene olefin random copolymers, propylene olefin random copolymers, ethylene propylene random copolymers, ethylene (1-butene) random copolymers, ethylene (1-pentene) olefin block copolymers, ethylene (1-hexene) random copolymers, ethylene (1-heptene) olefin block copolymers, ethylene (1-octene) olefin block copolymers, ethylene (1-nonene) olefin block copolymers, ethylene (1-decene) olefin block copolymers, propylene ethylene olefin block copolymers, ethylene (α -olefin) random copolymers, ethylene (1-butene) random copolymers, ethylene (1-pentene) olefin block copolymers, ethylene (1-hexene) olefin) random copolymers, ethylene (α -olefin) random copolymers, ethylene (1-butene) olefin) block copolymers, ethylene (1-butene) olefin) block copolymers, ethylene (1-olefin) copolymer, ethylene (e, ethylene (e) copolymer, ethylene (e) and ethylene (e) copolymer (e, Ethylene (alpha-olefin) block copolymers, amorphous polypropylenes, combinations thereof with polyethylenes (LLDPE, LDPE, HDPE, etc.), combinations thereof with polypropylenes, or combinations thereof, and the like. The olefin elastomer may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The density of the olefin elastomer is preferably 0.830g/cm³Above, more preferably 0.835g/cm³More preferably 0.840g/cm or more³Above, most preferably 0.845g/cm³The above. Further, the density of the olefin elastomer is preferably 0.890g/cm³The lower, more preferably 0.888g/cm³The following, furtherPreferably 0.886g/cm³The lower, particularly preferred is 0.885g/cm³The following. By setting the density in the above range, a stretchable laminate having more excellent suitability (conformability) can be provided. Further, the thermal stability and storage stability are improved. In addition, the process in the production of the elastomer layer can be further simplified, and the processing cost can be further suppressed.

The olefin-based elastomer preferably has a Melt Flow Rate (MFR) of 1.0g/10 min or more, more preferably 2.0g/10 min or more at 230 ℃ and 2.16 kgf. The olefin-based elastomer has an MFR of preferably 25.0g/10 min or less, more preferably 23.0g/10 min or less, still more preferably 21.0g/10 min or less, particularly preferably 20.0g/10 min or less, and most preferably 19.0g/10 min or less at 230 ℃ and 2.16 kgf. By setting the MFR within the above range, a stretchable laminate having more excellent suitability can be provided. Further, the thermal stability and storage stability are improved. In addition, the process in the production of the elastomer layer can be further simplified, and the processing cost can be further suppressed.

As the olefin elastomer, an α -olefin elastomer is preferably used. Among the α -olefin elastomers, at least 1 selected from the group consisting of ethylene elastomers, propylene elastomers and 1-butene elastomers is more preferably used. By using such an α -olefin elastomer as the olefin elastomer, a stretchable laminate having more excellent suitability can be provided. Further, the thermal stability and storage stability are improved. In addition, the process in the production of the elastomer layer can be further simplified, and the processing cost can be further suppressed.

Commercially available α -olefin elastomers can be used. Examples of commercially available products include "TAFMER" (registered trademark) series (e.g., TAFMER PN-2070, TAFMER PN-3560, etc.) manufactured by Mitsui chemical Corporation and "Vistamaxx" (registered trademark) series (e.g., Vistamaxx 3000, Vistamaxx 6202, Vistamaxx 7010, etc.) manufactured by Exxon Mobil Corporation.

The α -olefin elastomer is preferably produced using a metallocene catalyst. An α -olefin elastomer produced using a metallocene catalyst can provide a stretchable laminate having very excellent suitability. Further, the thermal stability and storage stability are improved. In addition, the process in the production of the elastomer layer can be further simplified, and the processing cost can be further suppressed.

Examples of the styrene elastomer include SIS elastomers and SBS elastomers. As the styrene-based elastomer, an SIS-based elastomer having a specific molecular structure can be used. Specifically, examples of the SIS-based elastomer include SIS-based elastomers having a styrene-isoprene-styrene block copolymer molecular structure with different terminal styrene block chain lengths (hereinafter, also referred to as specific SIS-based elastomers). By using such an SIS-based elastomer, a stretchable laminate having excellent holding power when stretched and adhered to another member and further excellent hand feeling can be obtained. The specific SIS-based elastomer may be used alone in 1 kind, or may be used in combination with 2 or more kinds.

Specific examples of the SIS-based elastomer include "Quintac 3390 (SL-159)" and "Quintac 3620" (styrene content: 14 wt%) manufactured by Zeon Corporation.

The MFR of the specific SIS-based elastomer at 200 ℃ and 5kgf is preferably 5.0g/10 min or more, more preferably 6.0g/10 min or more, and still more preferably 8.0g/10 min or more. The MFR of the specific SIS elastomer is preferably 25.0g/10 min or less, more preferably 23.0g/10 min or less, still more preferably 21.0g/10 min or less, particularly preferably 20.0g/10 min or less, and most preferably 18.0g/10 min or less. By setting the MFR within the above range, a stretchable laminate having further improved holding power when it is stretched and adhered to another member and further excellent hand feeling can be obtained, and the process for producing the elastomer layer can be further simplified, and further reduction in processing cost can be achieved.

The content ratio of the elastomer resin as the main component in the elastomer layer is preferably 50% by weight or more, more preferably 70% by weight or more, and further preferably 90% by weight or more. The content ratio of the elastomer resin as the main component is preferably 100 wt% or less, and more preferably 95 wt% or less. By setting the content ratio of the elastomer resin as the main component within the above range, the elastomer layer can exhibit sufficient elastomer characteristics.

The elastomer layer may contain any other suitable component within a range not impairing the effects of the present invention. Examples of such other components include other polymers, tackifiers, plasticizers, anti-deterioration agents, pigments, dyes, antioxidants, antistatic agents, lubricants, foaming agents, thermal stabilizers, light stabilizers, inorganic fillers, and organic fillers. These may be 1 kind only or 2 or more kinds. The content ratio of the other components in the elastomer layer is preferably 10 wt% or less, more preferably 7 wt% or less, further preferably 5 wt% or less, particularly preferably 2 wt% or less, and most preferably 1 wt% or less.

The thickness of the elastomer layer is preferably 20 μm or more, more preferably 30 μm or more. The thickness of the elastomer layer is preferably 200 μm or less, more preferably 160 μm or less, still more preferably 140 μm or less, particularly preferably 120 μm or less, and most preferably 100 μm or less. By setting the thickness of the elastomer layer within such a range, a stretchable laminate having more excellent suitability can be provided.

The elastomer layer may be 1 layer only, or may be 2 or more layers. In 1 embodiment, the elastomer layer has an intermediate layer and surface layers disposed on both sides of the intermediate layer. The intermediate layer and the surface layer may be formed using any suitable elastomer. Specifically, the elastomer can be used, and a styrene-based elastomer or an olefin-based elastomer is preferably used. The olefin elastomer is preferably used for the surface layer. By using the olefin elastomer, adhesiveness with another layer (for example, a nonwoven fabric layer) is improved. In addition, the intermediate layer preferably contains a white pigment. By including a white pigment, appearance properties suitable for sanitary articles can be obtained.

When the elastic layer has the intermediate layer and the surface layer, the thicknesses of the intermediate layer and the surface layer may be set to any appropriate values so that the thickness of the elastic layer falls within the above range. The thickness of the intermediate layer is preferably 18 μm or more, more preferably 28 μm or more. The thickness of the intermediate layer is preferably 94 μm or less, more preferably 56 μm or less, and still more preferably 46 μm or less. The thickness of the surface layer is preferably 1 μm or more. The thickness of the surface layer is preferably 4 μm or less, more preferably 3 μm or less, and still more preferably 2 μm or less. The thicknesses of the surface layers disposed on both sides of the intermediate layer may preferably be set to the same thickness.

In 1 embodiment, an activated elastomer layer is used as the elastomer layer. By using the activated elastomer layer, a stretchable laminate having both more excellent breaking strength and elongation can be obtained. The elastomeric layer may be activated by any suitable method. For example, the activation can be performed by the same method as the method for activating the nonwoven fabric.

D. Method for producing stretchable laminate

The stretchable laminate can be produced by any suitable method. Examples thereof include: (1) a method of laminating an elastomer layer extruded from a T die of an extruder and a nonwoven fabric layer drawn out from another roll, (2) a method of simultaneously extruding and laminating the elastomer layer and the nonwoven fabric layer, (3) a method of bonding separately prepared elastomer layer and nonwoven fabric layer with an adhesive, and (4) thermal lamination or ultrasonic bonding of the elastomer layer and the nonwoven fabric layer. As a bonding method, bonding by ultrasonic wave (ultrasonic fusion bonding) and bonding by an adhesive are preferably cited. The method for producing a stretchable laminate of the present invention includes, for example: activating the long fiber hydraulic entanglement non-woven fabric; and joining the activated long fiber hydroentangled nonwoven fabric and the elastomeric layer. The process for producing the stretchable laminate may be performed continuously with the process for producing the long fiber hydroentangled nonwoven fabric, or may be performed sequentially.

D-1. ultrasonic bonding

The ultrasonic bonding may be performed by any suitable method. By performing fusion bonding by ultrasonic bonding, the nonwoven fabric layer and the elastomer layer can be bonded with higher strength. Further, generation of a peculiar odor derived from the adhesive and the pressure-sensitive adhesive can be further suppressed, and obstruction of air permeability by the adhesive and the pressure-sensitive adhesive can be further prevented. In addition, the stretchable laminate can be produced at a lower cost.

Specifically, the ultrasonic fusion bonding can be performed by disposing a member to be bonded (for example, a laminate of an elastomer layer and a nonwoven fabric layer) between a member (generally referred to as a "horn") and a roll member (generally referred to as an "anvil") that are each configured to emit vibration energy by ultrasonic waves. Generally, the horn is disposed vertically above the joining target member and the anvil. The horn typically vibrates at 20000Hz to 40000Hz, transferring energy under pressure, typically in the form of frictional heat, to the components to be joined. By the frictional heat and pressure, a part of at least 1 of the members to be joined is softened or melted, and the layers are joined.

The pressing force between the horn and the anvil in the ultrasonic welding is preferably 100N to 1500N, more preferably 300N to 1300N, further preferably 500N to 1100N, and particularly preferably 700N to 1000N. By setting the pressing force between the horn and the anvil in the ultrasonic welding within the above range, flexibility is further improved, and a more satisfactory touch feeling can be achieved. In addition, the production speed of the stretchable laminate is further improved.

In 1 embodiment, ultrasonic welding bonding is generally performed by a method known as "continuous ultrasonic welding bonding". Continuous ultrasonic fusion bonding is generally used for sealing a member to be bonded that can be substantially continuously fed into a bonding apparatus. In the continuous ultrasonic fusion bonding, a horn is generally fixed, and a member to be bonded moves directly below the horn. A continuous ultrasonic fusion splice uses a fixed horn and a rotating anvil surface. In the continuous ultrasonic welding, a member to be welded is stretched between a horn and a rotary anvil. The horn is extended in a length direction generally toward the joining target member, and the vibration is moved to the material in an axial direction along the horn.

In another embodiment, the horn is of a rotary type, has a cylindrical shape, and rotates about a longitudinal axis. The input vibration is located in the axial direction of the welding head, and the output vibration is located in the radial direction of the welding head. The horn is disposed close to the anvil, and usually the anvil may be rotated so that the joining target member passes between the cylindrical surfaces at a linear velocity substantially equal to the tangential velocity of the cylindrical surfaces.

Ultrasonic fusion bonding is described in, for example, japanese patent laid-open nos. 2008-526552, 2010-195044, 2013-231249, 2015-16294, and us 5976316, the disclosures of which are incorporated herein by reference.

The ultrasonic bonding may be performed on the entire nonwoven fabric layer and the elastomer layer, or may be performed partially. In the case of ultrasonic bonding, the ratio of the area of the welded portions welded by ultrasonic welding (hereinafter also referred to as "welded area ratio") to the entire surface area of the resulting stretchable laminate is preferably 2% or more, more preferably 3% or more, further preferably 4% or more, and particularly preferably 5% or more. The ratio of the welding area is preferably 20% or less, more preferably 15% or less, still more preferably 10% or less, and particularly preferably 8% or less. By setting the ratio of the welding area within the above range, both the productivity and the adhesive strength of the stretchable laminate can be achieved.

In 1 embodiment, the surface of the rotary anvil preferably has an embossing pattern. Specific examples of such an embossed pattern include a continuous lattice shape, a discontinuous lattice shape, a continuous curved shape, a discontinuous curved shape, a continuous saw-tooth shape, a discontinuous saw-tooth shape, a continuous linear shape, a discontinuous linear shape, a circular shape (dot shape), an elliptical shape, a hollow circular shape, a hollow elliptical shape, an arc shape, and a hollow arc shape. The embossing pattern of the surface of the rotary anvil is disclosed in, for example, japanese patent application laid-open No. 2017-65253. The disclosure is incorporated into this specification by reference.

The shape of the tip portion of the convex portion (portion in contact with the member to be joined) constituting the embossed pattern may be any appropriate shape, for example, a circular shape. In the case of using an embossing pattern having a rounded tip portion, the diameter of the rounded portion is preferably 0.4mm or more, more preferably 0.45mm or more, and still more preferably 0.5mm or more. The diameter of the circular portion is preferably 1mm or less, more preferably 0.9mm or less, and further preferably 0.8mm or less. By setting the diameter within the above range, both the productivity and the adhesive strength of the stretchable laminate can be achieved. The embossing depth is preferably 0.5mm or more. The embossing depth is preferably 1.5mm or less, more preferably 1mm or less. By setting the embossing depth to the above range, both the productivity and the adhesive strength of the stretchable laminate can be achieved.

In addition, from the viewpoint of stabilizing the quality of the resulting stretchable laminate, it is preferable to perform ultrasonic fusion bonding while adjusting the temperature of the anvil to an arbitrary appropriate temperature. When the temperature fluctuation of the anvil is too large, the adhesive strength also fluctuates, and a stretchable laminate with stable quality cannot be obtained. The temperature of the anvil may be set to 5 to 90 ℃ by an absolute thermometer, for example, and may be adjusted so that the temperature of the anvil becomes ± 5 ℃. By setting the temperature of the anvil to the above range, it is possible to prevent the productivity from being lowered due to dew condensation or the like, and to prevent adverse effects on product characteristics such as curing of the nonwoven fabric and the elastomer layer.

D-2. adhesive-based joining

In another embodiment of the present invention, the nonwoven fabric layer and the elastomer layer are bonded to each other with an arbitrary appropriate adhesive. Preferably a hot melt adhesive is used. By using a hot melt adhesive, the necessity of adding a tackifier as a component of the elastomer layer is reduced, and for example, extrusion stability is improved, and the adhesion of the tackifier to the forming roll can be suppressed. In addition, the problem of line contamination due to volatile components contamination or the like caused by the thickener can be suppressed.

The hot melt adhesive may be applied to the entire surface of the nonwoven fabric layer, or may be applied to a part of the nonwoven fabric layer. When the hot melt adhesive is applied to a part of the nonwoven fabric layer, the hot melt adhesive is preferably applied so as to include at least the end of the nonwoven fabric layer.

As the hot melt adhesive, any suitable adhesive may be used. Examples thereof include a hot melt adhesive containing a styrene-based elastomer and a hot melt adhesive containing an olefin-based polymer. Preferably a hot melt adhesive comprising a styrenic polymer. Examples of such styrenic polymers include SIS-containing polymers, SBS-containing polymers, various hydrogenated products, and blends thereof. The hot melt adhesive may be used in a single amount of 1 kind, or may be used in combination of 2 or more kinds. When the hot melt adhesive contains a styrene-based polymer, the number of the styrene-based polymer may be 1 or 2 or more.

When the hot melt adhesive contains a styrene-based polymer, the content of the styrene-based polymer in the hot melt adhesive is preferably 10 to 90 wt%, more preferably 20 to 80 wt%, still more preferably 30 to 70 wt%, and particularly preferably 40 to 60 wt%.

The hot melt adhesive may also comprise any suitable other ingredients. Examples of such other components include liquid paraffin, a thickener, an antioxidant, an ultraviolet absorber, a light stabilizer, and a fluorescent agent. Such other components may be 1 kind only, or 2 or more kinds.

The tackifier is effective for improving the adhesion. The content ratio of the tackifier in the hot melt adhesive is preferably 10 to 90 wt%, more preferably 20 to 80 wt%, further preferably 30 to 70 wt%, and particularly preferably 40 to 60 wt%.

Examples of the tackifier include hydrocarbon-based tackifiers, terpene-based tackifiers, rosin-based tackifiers, phenol-based tackifiers, epoxy-based tackifiers, polyamide-based tackifiers, elastomer-based tackifiers, and ketone-based tackifiers. The number of the tackifiers may be 1 or 2 or more.

Examples of the hydrocarbon-based tackifier include aliphatic hydrocarbon resins, aromatic hydrocarbon resins (e.g., xylene resins), aliphatic cyclic hydrocarbon resins, aliphatic/aromatic petroleum resins (e.g., styrene/olefin copolymers), aliphatic/alicyclic petroleum resins, hydrogenated hydrocarbon resins, coumarone resins, and coumarone/indene resins.

Examples of the terpene-based tackifier include terpene-based resins such as α -pinene polymer and β -pinene polymer; modified terpene resins (e.g., terpene-phenol resins, styrene-modified terpene resins, hydrogenated terpene resins, etc.) obtained by modifying terpene resins (e.g., phenol modification, aromatic modification, hydrogenation modification, etc.); and the like.

Examples of rosin-based tackifiers include unmodified rosins (raw rosins) such as gum rosin and wood rosin; modified rosins obtained by modifying unmodified rosins by hydrogenation, disproportionation, polymerization, or the like (for example, hydrogenated rosins, disproportionated rosins, polymerized rosins, other chemically modified rosins, or the like); other various rosin derivatives; and the like.

Examples of the phenolic thickener include resol-type and novolak-type alkylphenols.

In addition, the tackifier may be a tackifier sold in the form of a blend with an olefin resin, a thermoplastic elastomer.

The hot melt adhesive may be applied to the nonwoven and/or elastomeric layer by any suitable method.

The stretchable laminate may be further subjected to stretching and activating treatment after lamination. Specifically, the stretchable laminate may be subjected to a stretching treatment in the width direction thereof, for example, a treatment of mechanically breaking the fiber structure in a partial region of the nonwoven fabric layer. By performing the above treatment, the stretchable laminate can be stretched with a smaller force. The activation treatment can be performed by the same method as the stretching treatment and the activation treatment described in the above item B. It is preferable to perform an activation treatment after lamination. By laminating the nonwoven fabric layer and the elastomer layer and then performing activation treatment, a stretchable laminate having more excellent elongation can be obtained.

In 1 embodiment, ultrasonic bonding and adhesive bonding may be used in combination. When used in combination, the nonwoven fabric layer and the elastomer layer may be bonded to each other entirely by ultrasonic bonding and by an adhesive, or may be partially bonded to each other by ultrasonic bonding and by an adhesive. Alternatively, the nonwoven fabric layer and the elastomer layer may be joined to each other entirely or partially by another joining method.

In one embodiment, a method for producing the stretchable laminate includes: activating the long fiber hydroentangled nonwoven fabric; and joining the activated nonwoven fabric and the elastomer layer by at least 1 joining method selected from the group consisting of ultrasonic welding and attachment by means of an adhesive layer. Preferably, the activation of the long fiber hydroentangled nonwoven fabric and the joining of the activated nonwoven fabric to the elastomeric layer are performed continuously in-line. By continuously performing these steps on-line, a stretchable laminate having a nonwoven fabric layer and an elastomer layer can be produced at a lower cost. Preferably, the method further comprises activating the bonded nonwoven fabric and elastomer layer.

In 1 embodiment, the method for producing the stretchable laminate further comprises shrinking the long fiber hydroentangled nonwoven fabric in the 1 st direction. As a method for shrinking the filament hydroentangled nonwoven fabric in the 1 st direction, any suitable method may be used. Examples thereof include: a method of stretching and shrinking the long fiber hydroentangled nonwoven fabric in a direction substantially orthogonal to the 1 st direction, a method of heating and shrinking the long fiber hydroentangled nonwoven fabric provided with heat shrinkability by any suitable method, and the like.

Specifically, the filament hydroentangled nonwoven fabric may be contracted in the 1 st direction according to the following procedure. The long fiber hydroentangled nonwoven was uniaxially stretched between 2 stretching rolls. Here, the peripheral speed of the stretching roll on the downstream side in the transport direction is set to be faster than the peripheral speed of the stretching roll on the upstream side, and the long fiber hydroentangled nonwoven fabric is stretched while applying tension thereto. Preferably, the stretching roll has a nip roll. The long fiber hydroentangled nonwoven fabric can be fixed to the stretching roll by conveying the long fiber hydroentangled nonwoven fabric in a state of being nipped by the stretching roll and the nip roll. In 1 embodiment, at least one of the stretching rollers is a heated roller. The long fiber hydroentangled nonwoven fabric can be contracted in the 1 st direction by a dry stretching method in which the long fiber hydroentangled nonwoven fabric is stretched in the atmosphere while being heated by using a heated roller. In 1 embodiment, the long fiber hydroentangled nonwoven fabric can be contracted in the 1 st direction by a wet stretching method in which the long fiber hydroentangled nonwoven fabric is stretched while being immersed in an arbitrary appropriate solution.

In one embodiment, the method for producing a stretchable laminate further comprises activating the elastomer layer. Activation of the elastomeric layer may be performed by any suitable method. For example, the elastomer layer can be activated by using the method exemplified as the method for activating the nonwoven fabric.

E. Use of the stretchable laminate of the present invention

The stretchable laminate of the present invention can be used for any suitable article that can effectively utilize the effects of the present invention. Namely, the article of the present invention includes the stretchable laminate. Such articles are typically sanitary goods, for example. Examples of such sanitary products include diapers (particularly, disposable diaper ears), crotch guards (supporters), and masks.

Examples

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples at all. The evaluation methods in examples and the like are as follows. Unless otherwise specified, parts means parts by weight and% means% by weight.

[ example 1]

The elastomer layer (hereinafter, also referred to as an elastic film) was extrusion-molded using 2 types of 3-layer (a layer/B layer/a layer) extrusion T-die molding machines. Specifically, an olefin-based resin 1 (product name: Vistamaxx 3980, manufactured by Exxon Mobil Corporation): 50 parts by weight of an olefin-based resin 2 (product name: 52518, HDPE, manufactured by National Petrochemical Company): 50 parts by weight of an A layer was put into an extruder, 46.5 parts by weight of a styrene-based resin 1 (product name: Quintac3390, manufactured by Zeon Corporation), 46.5 parts by weight of a styrene-based resin 2 (product name: Quintac3620, manufactured by Zeon Corporation) and 7 parts by weight of a White pigment (titanium oxide, product name: White PE MB 111413, manufactured by Ampacet) were put into a B layer of the extruder, and an elastic film 1 having a thickness of 50 μm (layer A/layer B/layer A: 2 μm/46 μm/2 μm) was extrusion-molded. The extrusion temperature was carried out under the following conditions. Layer A: 200 ℃, layer B: 230 ℃ and mold temperature: 230 ℃ to 230 ℃.

Using 2 uneven rolls having a tip radius R of 1mm and a pitch width of 7mm and having protrusions at the top and bottom, and an apparatus 2 which performs activation by stacking from top to bottom, a nonwoven fabric (PP long fiber hydraulic entangling type, basis weight of 19gsm) was activated stepwise from top to bottom at depths of 4.7mm and 7mm, respectively, to obtain an activated nonwoven fabric 1.

The activated nonwoven fabric 1 was directly laminated on both sides of the obtained elastic film 1, and ultrasonic bonding was performed to completely bond them. Ultrasonic bonding was carried out by ultrasonic welding and lamination using an ultrasonic welding apparatus (product of Herrmann, equipment name: MICROBOND (ULTRABOND 48: 20)) at a frequency of 20kHz (output intensity: 1800W) and a line speed of 100m/min in a state of 3 layers of nonwoven fabric/elastic film/nonwoven fabric being laminated. The embossed pattern roll used in welding was a roll having a dot pattern of 8% weld area and 0.7mm diameter. In this manner, a stretchable laminate 1 was obtained.

[ example 2]

A stretchable laminate 2 was obtained in the same manner as in example 1, except that an elastic film 2 having a thickness of 45 μm (layer a/layer B/layer a) ═ 1.8 μm/41.4 μm/1.8 μm was produced.

[ example 3]

A stretchable laminate 3 was obtained in the same manner as in example 1, except that an elastic film 3 having a thickness of 35 μm (layer a/layer B/layer a) ═ 1.4 μm/32.2 μm/1.4 μm was produced.

[ example 4]

A stretchable laminate 4 was obtained in the same manner as in example 1, except that an elastic film 4 having a thickness of 30 μm (layer a/layer B/layer a) ═ 1.2 μm/27.6 μm/1.2 μm was produced.

[ example 5]

Olefin resin 1 (product of Exxon Mobil Corporation, trade name: Vistamaxx 3980) was used for layer A: 50 parts by weight of an olefin-based resin 3 (product name: PP756C, rPP, available from SCGPLASTICS company): a stretchable laminate 5 was obtained in the same manner as in example 1, except that 50 parts by weight of the elastic film 5 was prepared.

[ example 6]

A stretchable laminate 6 was obtained in the same manner as in example 5, except that the elastic film 6 was prepared to have a thickness of 35 μm (layer a/layer B/layer a: 1.4 μm/32.2 μm/1.4 μm).

[ example 7]

Styrene resin 1 (product name: Quintac3390, manufactured by Zeon Corporation) was used in layer A: an elastic film 7 was produced in the same manner as in example 1 except that 95 parts by weight of styrene-based resin 1 (product name: Quintac3390, manufactured by Zeon Corporation) and 5 parts by weight of White pigment (product name: White PE MB 111413, manufactured by Ampacet) were used for layer B, and 100 parts by weight of this elastic film was used for layer B.

[ example 8]

Olefin resin 1 (product of Exxon Mobil Corporation, trade name: Vistamaxx 3980) was used for layer A: 50 parts by weight of an olefin-based resin 2 (trade name: 52518, HDPE, manufactured by national petrochemical company): an elastic film 8 having a thickness of 45 μm (layer a/layer B/layer a: 1.8 μm/41.4 μm/1.8 μm) was produced in the same manner as in example 1 except that 46.5 parts by weight of an olefin-based resin 4 (product name: Vistamaxx 6202, manufactured by Exxon Mobil Corporation), 46.5 parts by weight of an olefin-based resin 5 (product name: TAFMER PN-3560, manufactured by mitsui chemical) and 7 parts by weight of a White pigment (titanium oxide, product name: White PE MB 111413, manufactured by Ampacet), and the like were used in the layer B, and an elastic laminate 8 was obtained.

[ example 9]

SIS resin (manufactured by Kraton Polymers, Inc., trade name: Kraton D1165 PT): 213 parts by weight of a tackifier (manufactured by KOLON, trade name: SUKOREZ SU-100S): 619 parts by weight, liquid paraffin (trade name: White Oil Pharma Oyster 259, manufactured by Petroyag): 84 parts by weight of an antioxidant (product name: Irganox1010, manufactured by BASF): 10 parts by weight were mixed to obtain a hot melt adhesive.

The activated nonwoven fabric 1 obtained in example 1 and the non-activated nonwoven fabric (PP long fiber hydroentangled type, basis weight 19gsm) were striped on one side (width of adhesive layer: 1mm, interval: 1mm, coating weight: 8 g/m)²) A hot melt adhesive was applied to the elastic film 2 obtained in example 2, and the adhesive was bonded to both surfaces of the elastic film on a roll to obtain a laminate.

The obtained laminate was introduced into the activation apparatus used in example 1, to obtain a stretchable laminate 9.

[ example 10]

The stretchable laminate 2 obtained in example 2 was introduced into the activation apparatus used in example 1, and activated in stages at depths of 4mm and 6.7mm from the top to the bottom, to obtain a stretchable laminate 10.

[ example 11]

The nonwoven fabric (PP long fiber hydraulic entangled type, basis weight of 19gsm) was introduced into the activation apparatus used in example 1, and activated in stages at depths of 4mm and 6mm from top to bottom, to obtain an activated nonwoven fabric 2. A stretchable laminate 11 was obtained in the same manner as in example 2, except that the activated nonwoven fabric 2 thus obtained was used.

[ example 12]

A stretchable laminate 12 was obtained in the same manner as in example 3, except that the embossing pattern roll used for ultrasonic welding was a roll having a dot pattern with a welding area of 6% and a diameter of 0.7 mm.

[ example 13]

A stretchable laminate 13 was obtained in the same manner as in example 3, except that the embossing pattern roll used for ultrasonic welding was a roll having a dot pattern with a welding area of 10% and a diameter of 0.9 mm.

[ example 14]

A stretchable laminate 14 was obtained in the same manner as in example 9, except that the elastic film 14 obtained in example 1 was introduced into an activation apparatus and activated to a depth of 7 mm.

[ example 15]

A stretchable laminate 15 was obtained in the same manner as in example 9, except that the elastic film 15 obtained in example 2 was introduced into an activation apparatus and activated at a depth of 7mm, one side of the elastic film was a nonwoven fabric (PP long fiber hydroentangled type, basis weight of 19gsm), and the other side of the elastic film was an activated nonwoven fabric (a nonwoven fabric activated at a depth of 4mm or 5mm by introducing PP carded type, basis weight of 20gsm into the activation apparatus).

[ example 16]

A stretchable laminate 16 was obtained in the same manner as in example 15, except that a long fiber hydroentangled nonwoven fabric having a basis weight of 22gsm (PP long fiber hydroentangled type, basis weight of 22gsm) was used as the long fiber hydroentangled nonwoven fabric.

[ example 17]

A stretchable laminate 17 was obtained in the same manner as in example 2, except that a long fiber hydroentangled nonwoven fabric (PP long fiber hydroentangled type, basis weight: 22gsm) was introduced into an activation apparatus and activated at a depth of 4.7mm or 7 mm.

[ example 18]

A mechanical tension was applied to the nonwoven fabric (PP long fiber hydraulic entangled type, basis weight 19gsm) in the longitudinal direction, and the width in the direction perpendicular to the longitudinal direction was contracted by 50%, to obtain a nonwoven fabric contracted in the width direction. A stretchable laminate 18 was obtained in the same manner as in example 2, except that the obtained nonwoven fabric was used without activation.

[ example 19]

A mechanical tension was applied to the nonwoven fabric (PP long fiber hydraulic entangled type, basis weight 19gsm) in the longitudinal direction, and the width in the direction perpendicular to the longitudinal direction was contracted by 40%, to obtain a nonwoven fabric contracted in the width direction. A stretchable laminate 19 was obtained in the same manner as in example 2, except that the obtained nonwoven fabric was used.

[ example 20]

A mechanical tension was applied to a nonwoven fabric (PP long fiber hydraulic entangled type, basis weight: 22gsm) in the longitudinal direction, and the width in the direction perpendicular to the longitudinal direction was contracted by 50%, to obtain a nonwoven fabric contracted in the width direction. A stretchable laminate 20 was obtained in the same manner as in example 1, except that the obtained nonwoven fabric was used.

[ example 21]

A mechanical tension was applied to a nonwoven fabric (PP long fiber hydraulic entangled type, basis weight: 22gsm) in the longitudinal direction, and the width in the direction perpendicular to the longitudinal direction was contracted by 50%, to obtain a nonwoven fabric contracted in the width direction. A stretchable laminate 21 was obtained in the same manner as in example 3, except that the obtained nonwoven fabric was used.

[ example 22]

A stretchable laminate was obtained in the same manner as in example 1, except that the elastic film 15 obtained in example 15 was used and a nonwoven fabric (PP long fiber hydroentangled type, basis weight of 19gsm) and a nonwoven fabric (PP carded type, basis weight of 24gsm) were laminated on both sides of the elastic film 15. The resulting stretchable laminate was introduced into the activation apparatus used in example 1, and activated at a depth of 4mm or 5mm to obtain a stretchable laminate 22.

Comparative example 1

A stretchable laminate C1 was obtained in the same manner as in example 2, except that a nonwoven fabric obtained by activating a nonwoven fabric (PP spunbond, basis weight of 19gsm) in the same manner as in example 1 was used as the nonwoven fabric layer.

Comparative example 2

An elastic laminate C2 was obtained in the same manner as in example 2, except that a nonwoven fabric obtained by activating a nonwoven fabric (PP carded, basis weight: 24gsm) in the same manner as in example 1 was used as the nonwoven fabric layer.

Comparative example 3

A stretchable laminate C3 was obtained in the same manner as in example 10, except that a nonwoven fabric obtained by activating a nonwoven fabric (PP spunbond, basis weight of 19gsm) in the same manner as in example 1 was used as the nonwoven fabric layer, and the nonwoven fabric and the elastomer layer were joined together and subjected to an activation treatment in a laminated state in the same manner as in example 10.

Comparative example 4

An elastic laminate C4 was obtained in the same manner as in example 10, except that a nonwoven fabric obtained by activating a nonwoven fabric (PP carded, basis weight 24gsm) in the same manner as in example 1 was used as the nonwoven fabric layer, and activation treatment was performed in a state in which the nonwoven fabric layer and the elastic layer were laminated.

Comparative example 5

An elastic laminate C5 was obtained in the same manner as in example 2, except that a nonwoven fabric (PP carded, basis weight: 19gsm) was used as the nonwoven fabric layer.

Comparative example 6

A stretchable laminate C6 was obtained in the same manner as in example 2, except that a nonwoven fabric (PET spunlace, basis weight 24gsm) was used as the nonwoven fabric layer.

Comparative example 7

A stretchable laminate C7 was obtained in the same manner as in example 2, except that a nonwoven fabric (PET spunlace, basis weight of 30gsm) was used as the nonwoven fabric layer.

(reference example 1)

A stretchable laminate C8 was obtained in the same manner as in example 2, except that a nonwoven fabric obtained by activating a nonwoven fabric (PP spunlace, basis weight of 30gsm) in the same manner as in example 1 was used as the nonwoven fabric layer.

(reference example 2)

A stretchable laminate C9 was obtained in the same manner as in example 2, except that a nonwoven fabric (PP spunlace, basis weight of 30gsm) was used as the nonwoven fabric layer.

[ evaluation ]

The nonwoven fabrics used in examples, comparative examples, and reference examples, and the stretchable laminates obtained in examples, comparative examples, and reference examples were evaluated as follows. The results are shown in tables 1 and 2.

< tensile test >

The tensile test was carried out by subjecting the nonwoven fabric, the activated nonwoven fabric, and the resulting stretchable laminate to the following test. The nonwoven fabric, activated nonwoven fabric, and the resulting stretchable laminate were cut into a width of 50mm and a length of 10cm so that the direction (CD) orthogonal to the film flow direction (MD) was a long side, and these were used as samples. Each sample was mounted on a tensile tester (product name: Z00051 kN, manufactured by ZwickRoell) so that the distance between chucks was 40mm, and was stretched at a stretching speed of 500mm/min until it broke. The breaking strength and the elongation at 5N (nonwoven fabric and activated nonwoven fabric) or 10N (stretchable laminate) were measured.

From the measurement results of the elongation at 10N and the breaking strength of the stretchable laminate obtained in the tensile test, whether both the elongation and the breaking strength can be satisfied was evaluated according to the following criteria. In addition, any range that does not satisfy the following is not defined as "possible".

40N or more and 100% or more: the best is

35N or more and 90% or more: good wine

30N or more and 70% or more: can be used for

< bad smell >

Using a stretchable laminate of 100cm²As a sample. The sample was sealed in a glass bottle having a capacity of 200ml, and stored in a heating oven at 50 ℃ for 1 day. Thereafter, the reaction mixture was taken out of the oven and returned to room temperature, and then odor was observed. The one who had no odor at all was recorded as "best", the one who had a slight sensation but no discomfort as "good", and the one who had a slight discomfort as "good".

< weight of nonwoven Fabric >

Cutting the non-woven fabric into 100cm by using an electronic balance²The weight of the sample was measured and converted to g/m²Units.

[ Table 1]

[ Table 2]

[ Table 3]

The stretchable laminates obtained in examples 1 to 22 were excellent in elongation and breaking strength. Further, the same performance as that of the stretchable laminates of reference examples 1 and 2 using the spunlace nonwoven fabric was exhibited without using the high-cost spunlace nonwoven fabric.

Industrial applicability

The stretchable laminate of the present invention can be used for any suitable article that can effectively utilize the effects of the present invention. The article of the present invention comprises the stretchable laminate of the present invention. Such articles are typically sanitary goods, for example. Examples of such sanitary products include diapers (particularly disposable diaper ears), crotch guards, and masks.

Description of the reference numerals

100 stretchable laminate

10 elastomeric layer

20 non-woven fabric layer

20a non-woven fabric layer

20b non-woven fabric layer

30 through hole