JP2001009947A - Composite sheet having stretchability and manufacture of the composite sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite sheet having large stretchability in one direction while effectively using a rubber elastic material and air permeability, moisture permeability. SOLUTION: The composite sheet 10 comprises a nonwoven fabric 11 in which fibers 11a are arranged substantially in a longitudinal direction and a netted film 12 connected onto the fabric 11. The film 12 is made of a thermoplastic elastomer. In this case, the film 12 is held at a flow starting temperature or higher of the elastomer in the state of elongating in a direction perpendicular to an arranging direction of the fibers 11a. Thus, openings 12a are enlarged in a lateral direction and its restoring force is lost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite sheet in which a nonwoven fabric and a thermoplastic elastomer web are joined and has elasticity in one direction, and a method for producing the same.
In particular, the present invention relates to a breathable and moisture-permeable stretch composite sheet used for clothing such as stretchable bandages, supporters, cuffs of clothes, stretchable elastic portions such as diapers, medical and sanitary materials, and the like.

[0002]

2. Description of the Related Art With regard to this type of stretchable composite sheet,
Conventionally, various sheets have been proposed (Japanese Unexamined Patent Publication No.
No. 77464, JP-A-9-132856, JP-A-9-279453, Japanese Patent Application No. 10-34242.
No.).

[0003] However, these composite sheets have poor elasticity characteristics as compared with the ratio of the amount of rubber elastic bodies used, because the rubber elastic bodies are not efficiently arranged in the direction of extension. In order to manufacture these products at low cost,
Although a wide rubber elastic web is required, rubber materials are generally difficult to mold, and manufacturing a wide web is inexpensive considering not only equipment costs but also workability and yield. It is difficult.

[0004] Stretchable composite sheets include those requiring sanitary materials such as diapers and the like, which need to be stretchable in the vertical direction and those which need to be stretchable in the horizontal direction, depending on the parts used. .

[0005] These stretchable composite sheets are used for the human body and animals as clothing, medical supplies, sanitary materials, diapers, and the like. It is necessary that the human body has no stuffiness. In these applications, it is required to have a soft touch like cloth. Therefore, if the rubber elastic body film is directly bonded to a nonwoven fabric or the like, the above-mentioned stuffiness cannot be eliminated or the cloth-like tactile sensation cannot be secured. There is also an example in which a net-like material is used and the surface layer is a film layer (Japanese Patent Application Laid-Open No. 59-59901). However, in the case of a net, a rubber elastic material in an unintended direction is wasted. It is difficult to produce a fine and flexible web at low cost.

SUMMARY OF THE INVENTION It is an object of the present invention to use a rubber elastic material effectively while having a large elasticity in one direction,
An object of the present invention is to provide a composite sheet having moisture permeability.

Another object of the present invention is to provide a method for manufacturing a composite sheet which can easily manufacture the above-mentioned composite sheet.

[0008]

According to the present invention, there is provided a composite sheet according to the present invention, wherein inelastic fibers are arranged in one direction, and the elongation in a direction perpendicular to the arrangement direction of the fibers is 100% or more. A non-woven fabric, a web having a vent formed of a thermoplastic elastomer bonded to the non-woven fabric and having vent holes, wherein the thermoplastic elastomer flows in a state of being stretched in a direction perpendicular to the direction in which the inelastic fibers are arranged. And a web whose restoring force has been eliminated by being maintained at a temperature equal to or higher than the starting temperature.

In the present invention, a nonwoven fabric in which inelastic fibers are arranged in one direction is used, but the arrangement of the fibers is not limited to the case where the fibers are completely arranged in one direction, and most of the fibers are arranged in one direction. , The case where they are arranged in almost one direction is also included. In addition, although the degree of arrangement has various expression methods, it is often indicated by a ratio of vertical strength to horizontal strength, that is, a value obtained by dividing vertical strength by horizontal strength, and this value is at least 3 or more, preferably 10 or more. is there.

[0010] In the composite sheet of the present invention, a web made of a thermoplastic elastomer and having air holes is joined to a nonwoven fabric in which inelastic fibers are arranged in one direction.
Although hardly deformed in the direction in which the fibers are arranged, the fiber has great elasticity in a direction perpendicular to the direction. In addition, since the web made of the elastomer has air holes, the air permeability is not impaired even if the elastomer web is used.

The pores of the elastomer web may be fine. This is because the ventilation holes are expanded by the extension. In particular, the elastomeric web used in the composite sheet of the present invention is bonded to the nonwoven fabric in a state where it is stretched in a direction perpendicular to the direction in which the fibers constituting the nonwoven fabric are arranged, and the stretching tension is lost. Therefore, the air holes in the elastomer web expand in the direction perpendicular to the arrangement direction of the fibers (the direction in which the composite sheet expands and contracts), thereby improving the efficiency of use of the elastomer in the direction in which the composite sheet expands and contracts. Further, in a state where the elastomer web is bonded to the nonwoven fabric, the stretching tension has already disappeared, so that the stretching of the elastomer web does not affect the elasticity of the composite sheet.

The stretching direction of the thermoplastic elastomer web is determined according to the desired stretching direction of the composite sheet. That is, the composite sheet having elasticity in the longitudinal direction is stretched in the vertical direction, and the composite sheet having elasticity in the horizontal direction is stretched in the horizontal direction. Also, the thermoplastic elastomer web may be biaxially stretched, in which case,
If the extension ratio in one direction is made higher than the extension ratio in the other direction and the extension ratio in one direction is relatively high, this is included in the extension in one direction in the present invention.

In the composite sheet of the present invention, the nonwoven fabric is
The fibers may be drawn in the direction of arrangement. Thereby, the elongation of the nonwoven fabric in the fiber arrangement direction is suppressed. Further, the web may be a film provided with openings as vents or a nonwoven fabric made of thermoplastic elastomer fibers.
In this case, in order to further improve the use efficiency of the elastomer in the stretching direction of the composite sheet, when the web is a film, the opening is preferably long in a direction perpendicular to the direction in which the inelastic fibers are arranged. In the case of a nonwoven fabric, it is preferable that the arrangement direction of the fibers is a direction perpendicular to the arrangement direction of the inelastic fibers.

The method for producing a composite sheet according to the present invention comprises the steps of: forming a nonwoven fabric in which inelastic fibers are arranged in one direction; forming a web made of a thermoplastic elastomer having ventilation holes; Stretching the web in one direction, heating the stretched web to a temperature equal to or higher than the flow start temperature of the thermoplastic elastomer to eliminate the restoring force of the web, the nonwoven fabric, and the restoring force Joining the lost web so that the direction of arrangement of the inelastic fibers and the direction of extension of the web are perpendicular to each other.

According to the method for producing a composite sheet of the present invention,
The composite sheet of the present invention is easily and efficiently manufactured. The nonwoven fabric and the thermoplastic elastomer web may be manufactured separately, and the manufacturing and joining may be performed in separate steps, or the manufacturing and joining may be performed in a series of steps.

In the present invention, the term "longitudinal direction" used in describing the expansion / contraction direction of the composite sheet means the feed direction of the nonwoven fabric, the web and the composite sheet in a series of manufacturing processes, and the "horizontal direction". The “direction” means a direction perpendicular to the longitudinal direction, that is, the width direction of the nonwoven fabric or web.

The fiber in the present invention means a fiber in a broad sense including both short fibers and continuous filaments.

The non-woven fabric comprising the inelastic fiber of the present invention must be a non-woven fabric in which the fibers are arranged in one direction, and the non-woven fabric has a non-woven fabric whose elongation in a direction perpendicular to the arrangement direction is 100% or more. Need to be. It is difficult to obtain an elongation of 100% or more in a nonwoven fabric in which fibers are not arranged, and there is no point in combining with a thermoplastic elastomer.

The elongation of 100% or more of the present invention is a direction perpendicular to the direction in which the fibers are arranged.
In this direction, a composite sheet having dimensional stability is obtained.

The nonwoven fabric comprising the inelastic fiber of the present invention may be a nonwoven fabric obtained by stretching a spunbonded nonwoven fabric or a melt-blown nonwoven fabric, or the longitudinally stretched nonwoven fabric of the present inventors.
Laterally stretched nonwoven fabric (Japanese Patent Publication No. 3-36948,
No. 0-204767) or a non-woven fabric made of long fiber filaments such as a non-woven fabric in which tow is opened and arranged in one direction. These long fiber filaments do not fall off even after several hundred times of repeated expansion and contraction, and are suitable for so-called lint-free applications. In addition, the stretched nonwoven fabric has strength and dimensional stability in the stretching direction, and the stretched nonwoven fabric is a glossy nonwoven fabric, so that the properties of this stretching can be used in clothing and the like.

When the fibers used as the non-woven fabric comprising the inelastic fibers used in the present invention are short fibers,
Card rising web, wet and dry short fiber non-woven fabric,
A short fiber nonwoven fabric made of a needle punched nonwoven fabric or the like can also be used. Especially in the web by the card machine used in the spinning process, the short fibers are already arranged vertically,
Particularly suitable for the present invention.

[0022]

Next, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
It is a top view of a composite sheet which is an embodiment of. The composite sheet 10 shown in FIG. 1 is obtained by joining a reticulated film 12 made of a thermoplastic elastomer to one surface of a stretched nonwoven fabric 11 in which inelastic fibers 11a are arranged in a substantially vertical direction. The reticulated film 12 is provided with a large number of laterally long openings 12a as ventilation holes.

The nonwoven fabric 1 used for the composite sheet 10
In No. 1, since the fibers 11a are arranged and stretched in the vertical direction, the deformation in the vertical direction is small, but can be largely deformed in the horizontal direction, which is a direction substantially perpendicular to the arrangement direction of the fibers 11a. That is, the nonwoven fabric 11 in which the fibers 11a are arranged in one direction and stretched,
In the direction perpendicular to the direction in which the fibers 11a are arranged, the fibers 11a uniformly exhibit large elongation without any breakage.
It has the property that it hardly deforms (elongation of several%) in the arrangement direction of a. The breaking elongation of the nonwoven fabric 11 in the direction perpendicular to the direction in which the fibers 11a are arranged is 100% or more, preferably 200% or more, and most preferably 300% or more. It is difficult for a nonwoven fabric in which the fibers 11a are not arranged to have a breaking elongation of 100% or more, and there is no point in combining with a thermoplastic elastomer. As a result of the experiment, it was confirmed that when the elongation at break was 100% or more, the composite with the elastomer exhibited a repeated elasticity of 200% or more.

The nonwoven fabric 11 is not particularly limited as long as the fibers 11a are arranged in one direction. In addition, even if it is a nonwoven fabric in which the fibers 11a are arranged and stretched in both the vertical and horizontal directions, if the vertical and horizontal balance is broken by increasing the stretching ratio in one direction, the fibers are stretched in one direction in the present invention. It can be used as a non-woven fabric.

By joining the reticulated film 12 made of a thermoplastic elastomer to such a nonwoven fabric 11, it is stretchable in the horizontal direction, but hardly stretches in the vertical direction and has excellent dimensional stability. A composite sheet 10 is obtained.

Further, since the reticulated film 12 is provided with a large number of openings 12a, even if an elastomer is used to give the composite sheet 10 a stretching function,
It has air permeability and moisture permeability. Moreover, these openings 12a
Is long in the transverse direction, the efficiency of use of the elastomer in the stretch direction, that is, the transverse direction, is high, and efficient stretch characteristics can be obtained with a small amount of elastomer.

As the thermoplastic elastomer, elastomers such as polyolefin, synthetic rubber, polyester, polyamide and polyurethane are used. Among them, synthetic rubbers and polyurethanes obtained by copolymerizing styrene and olefinic monomers are suitable for the thermoplastic elastomer used in the present invention in that they expand and contract at a high magnification and have low stress during expansion and contraction. Particularly, synthetic rubber of SEBS is most suitable.

As the fiber 11a, any of a long fiber filament and a short fiber (short fiber) can be used as long as it can have a structure having air permeability and moisture permeability when formed into a nonwoven fabric. The nonwoven fabric composed of long fiber filaments does not fall off even after repeated expansion and contraction of several hundred times, and is suitable for so-called lint-free use. Examples of the nonwoven fabric composed of long fiber filaments include a spunbonded nonwoven fabric, a nonwoven fabric obtained by stretching a meltblown nonwoven fabric, and a nonwoven fabric obtained by opening a tow. On the other hand, a nonwoven fabric made of short fibers has a good feel like cotton and is suitable for use in direct contact with the skin. As a nonwoven fabric composed of short fibers, there is a web or the like obtained from a card.

Polymers compatible with the fiber 11a include polyethylene, polypropylene, polyester,
Thermoplastic resins such as polyamide, polyvinyl chloride resin, polyurethane, and fluorine resin, and modified resins thereof can be used. In addition, resins to which wet or dry spinning means can be applied, such as a polyvinyl alcohol-based resin and a polyacrylonitrile-based resin, can also be used, and polyester and polypropylene are particularly preferable.
Fibers made of a polymer having rubber elasticity such as polyurethane are excluded.

Next, an example of a method for manufacturing the above-described composite sheet 10 will be described with reference to the process chart of FIG.

The manufacturing process of the composite sheet 10 is roughly divided into a process for manufacturing the nonwoven fabric 11, a process for manufacturing the elastomer web, and a process for joining these.

In the step of manufacturing the nonwoven fabric 11, first, a web in which the fibers 11a are arranged in a substantially vertical direction is obtained by using an appropriate spinning device (step 101). Then
This web is stretched in the arrangement direction of the fibers 11a, thereby obtaining a longitudinally stretched nonwoven fabric (Step 102).

On the other hand, in the step of producing the elastomer web, first, a transverse slit is formed in the film made of the elastomer (step 103). Next, the film in which the slit is formed is stretched or stretched in the horizontal direction (step 104). As a result, the film shrinks in the vertical direction, and the portion where the slit is formed expands in the horizontal direction, forming an opening 12a. Since the slit is formed in the horizontal direction, the opening 12a is longer in the horizontal direction. Further, by forming the slits in a staggered manner, an opening pattern as shown in FIG. 1 can be obtained.

Next, the film stretched in the horizontal direction is heated as it is at a temperature equal to or higher than the flow start temperature of the material constituting the film (step 105). By maintaining this state, the restoring force of the film disappears, and even if the tension applied to the film is removed, the film maintains the shape shown in FIG. 1, whereby the reticulated film 12 is formed. That is, the heating in this step is performed while the tension is applied to the film until the tension disappears. In order to shorten the heating time, the heating temperature is preferably from the above-mentioned flow start temperature to 10 to 20 ° C, more preferably from the above-mentioned flow start temperature to 30 to 50 ° C.

The flow start temperature is the glass transition temperature when the hard segment of the elastomer is a non-crystalline polymer, and the flow of the elastomer starts at the temperature or higher. If the hard segment is a crystalline polymer, its flow onset temperature is the melting temperature of the crystal, above which temperature the elastomer begins to flow. The glass transition temperature and melting temperature of the thermoplastic polymer are determined according to JIS K7121 according to DS.
It is measured by a C apparatus. In addition, the glass transition temperature or the melting temperature is generally lower in the case of a thermoplastic elastomer than in the case of measuring the hard segment polymer alone.

The final film width (length in the horizontal direction)
Is obtained by stretching the film in the initial stage in the horizontal direction, so that the width of the film in the initial stage is determined in consideration of the final film width and the stretching ratio of the film.

Here, the stretching of the film in the lateral direction and the heating are performed separately, but they may be performed simultaneously. However, since the film is made of an elastomer that is a rubber elastic material and is stretched uniformly by stretching under heating at room temperature or low temperature,
Preferably, the stretching step and the heating step are separate steps.

Then, the nonwoven fabric 11 obtained as described above and the reticulated film 12 are joined so that their respective positions in the width direction are matched (step 106). Since the reticulated film 12 is made of a thermoplastic elastomer, the reticulated film 12 can be obtained only by heating the reticulated film 12.
Easily adheres to the nonwoven fabric 11. Therefore, the nonwoven fabric 11 and the reticulated film 12 can be easily and inexpensively joined without using an adhesive or the like.

In this joining step, the film before stretching is supplied, and the stretched film is superimposed on the nonwoven fabric 11 and heated, so that the restoring force of the film is lost and the joining of the film and the nonwoven fabric 11 is performed. May be performed simultaneously.

Hereinafter, each of the above-described steps will be described in detail.

(1a) Nonwoven Fabric Manufacturing Process The nonwoven fabric used in the present invention can be manufactured by a melt-blowing method or a spunbonding method, which is a usual nonwoven fabric spinning method. Hereinafter, the production method by the melt blow (MB) method and the production method by the spun bond (SB) method will be described together with the production apparatus.

First, an example of a method for producing a nonwoven fabric by a melt blow method will be described with reference to FIGS.

The apparatus shown in FIG. 3 is an apparatus for spinning and drawing a fiber.
And a conveyor 207, a drawing cylinder 211, take-off nip rolls 214a and 214b.
And the like.

The melt blow (MB) die 201 has a number of nozzles 203 at the tip and a gear pump (not shown).
A number of fibers 51 are formed by extruding the molten resin 50 fed from the nozzle 203 from the nozzle 203. FIG. 1 shows a cross section of the melt blow die 201 for clarifying the structure. Air reservoirs 205a and 205b are provided on both sides of the nozzle 203. The high-pressure heating air heated to a temperature equal to or higher than the melting point of the resin is sent into these air reservoirs 205a and 205b.
a and 205b are ejected from the slits 206a and 206b at the tips. As a result, the fiber 51 extruded from the nozzle 203 is maintained in a draftable molten state, and the fiber 51 is drafted by frictional force due to the ejection of hot air, so that the diameter of the fiber 51 is reduced. The above mechanism is the same as in the ordinary MB method. The temperature of the high-pressure heating air is 80 ° C. or higher, preferably 120 ° C. or higher, more preferably 200 ° C. or higher than the spinning temperature of the fiber 51.
Increase by at least ℃.

In the method of forming the fiber 51 using the melt blow die 101, the temperature of the fiber 51 immediately after being extruded from the nozzle 203 is made sufficiently higher than the melting point of the fiber 51 by increasing the temperature of the heating air. Therefore, the molecular orientation of the fiber 51 can be reduced.

By providing a difference between the flow rates of the two airs in the air reservoirs 205a and 205b, and making the flow from one air reservoir 205a smaller than that from the other air reservoir 205b, the outflow direction of the fiber 51 from the nozzle 203 is changed. Is inclined by an angle α with respect to the extrusion direction of Giving the angle α to the outflow direction of the fiber 51 can be realized by inclining the melt blow die 201 itself, or both can be used in combination.

Below the melt blow die 201, a conveyor 207 for conveying the fiber 51 extruded from the nozzle 203 is arranged. Here, spray nozzles 208a and 208b are provided between the melt blow die 201 and the conveyor 207. The spray nozzles 208a and 208b spray atomized water from the front side and the back side of the fiber 51 toward the conveyor 207 side, whereby the fiber 51 is cooled and solidified. Although a plurality of spray nozzles 208a and 208b are actually installed, only one each is shown in FIG. 3 to avoid complexity. With the force of spraying this mist of water,
The fibers 51 are integrated as a web 52 on a conveyor 207 at an angle β greater than α.

The conveyor 207 is installed with an inclination of an angle γ from the horizontal plane, with the take-up direction lower than the landing point of the fiber 51. The spray nozzle 208
The cooling medium ejected from a and 208b does not necessarily need to contain moisture, and may be cold air. As described above, the fibers 5 of the web 52 on the conveyor 207 are arranged in the vertical direction due to the effects of the inclination of the conveyor 207 and the force of the air or mist.

In the spinning unit, the fibers 51 can be well arranged on the conveyor 207 by spinning while being inclined with respect to the conveyor surface. As means for skew the spinning in this way, the nozzle 203
Is effective with respect to the conveyor 207, the fiber 51 is skewed with the aid of a fluid, and the conveyor 207 is inclined with respect to the pushing direction of the fiber 51. Further, when it is difficult to sufficiently arrange them by only one of the skew feeding methods, a plurality of means may be combined.

When the fiber 51 is skewed with the aid of the fluid, it is desirable that the fluid be heated when the fluid is used near the nozzle. When no fluid is used near the nozzle, it is necessary to actively heat the fiber 51 near the nozzle. This is to minimize the molecular orientation when the diameter of the fiber 51 is reduced by drafting. In the spinning stage, the molecular orientation of the fibers 51 is made as small as possible, but it is desirable that the individual fibers 51 are arranged as vertically as possible.

The fluid used to skew the fiber 51 is most preferably a cold fluid in the vicinity of the conveyor, particularly a fluid containing mist of water. This is because by quenching the spun fiber 51, the influence of heat is prevented and crystallization does not proceed. If the influence of heat such as spinning and a heating fluid remains, the fibers 51 on the conveyor 207 are subjected to heat treatment, so that the crystallization of the fibers 51 progresses, and the drawability decreases. The drawability is significantly affected by heat, particularly when the fiber 51 is made of polyester, and is also seen with polypropylene. In the present embodiment, water is sprayed. However, the quenching effect by cooling the melted fiber 51 with water improves stretching suitability such as achievement of a high stretching ratio and high strength. Further, the spray nozzles 208a, 208
b, the spun web 52
Can be attached to the conveyor 207, which is also effective in improving spinning stability and alignment of the fibers 51.

The spray nozzles 208a, 208b
To the liquid sprayed from above, a so-called spinning and drawing oil agent, that is, an oil agent capable of imparting properties such as stretchability and static electricity removal may be added. Thereby, the fiber 51
Stretchability, fluff is reduced, and strength and elongation after stretching are also improved.

Since the cooled web 52 does not have self-adhesiveness, the web 52 may be scattered on the conveyor 207 by air flow or the like as it is.
7 is sucked by a negative pressure suction nozzle 210 provided linearly in the width direction of the conveyor on the back side of the conveyor 7 to prevent scattering.

As a type of the conveyor 207, there is a drum screen type which is frequently used for a melt blown nonwoven fabric in addition to the flat belt type conveyor shown in the figure. The inclination in the drum screen type means that the ejection direction of the fiber 51 from the nozzle 203 is inclined from the vertical to the winder direction. Conveyor 207
The various materials used in the production of non-woven fabrics such as metal wires and plastic wires can be used as the material of the non-woven fabrics. The various methods used can be used. A particularly effective net weave is a satin weave in which meshes are arranged vertically. This enhances the longitudinal arrangement effect of the fibers 51,
The strength of is improved.

The suction of the web 52 by the negative pressure suction nozzle 210 not only stabilizes the web 52 that has become skewed and becomes unstable, but also removes the heat remaining in the web 52. There is also an effect. In this case, it is important that the negative pressure suction is performed linearly in the width direction of the conveyor 207 and with a narrow width. In other words, the negative pressure suction of the web 52 in the melt blow method mainly aims at increasing the arrangement of the fibers 51, and further prevents the fibers 51 from scattering on the conveyor 207,
The purpose is to remove the heat of the fiber 51 on the sheet 07 and to enhance the drawability. Furthermore, negative pressure suction is applied to the web 5
2 also removes the moisture attached thereto, and thus has the effect of reducing the influence of moisture in the subsequent stretching step. In the case of polyester, negative pressure suction is preferable because moisture greatly affects the stretchability, and the stretch ratio and the web strength after stretching are reduced.

The web 52 on the conveyor 207 is sandwiched between the stretching cylinder 211 heated to the stretching temperature and the pressing rubber roll 212 on the back side of the conveyor loading surface, transferred onto the stretching cylinder 211, and further nipped by the pressing rubber roll 213. , And adhere to the stretching cylinder 211. The web 52 adhered to the stretching cylinder 211 is
1 and subsequent take-off nip rolls 214a, 214b (2
14b is stretched in proximity by a speed difference with a rubber roll),
The vertically stretched nonwoven fabric 53 is obtained.

Proximity stretching refers to a method of stretching a web based on the difference in surface speed between two adjacent rolls, in which stretching is performed while maintaining a short distance between stretching (distance from the start point to the end point of stretching). It is desirable that the distance between stretching is 100 mm or less. In particular, when the fibers are not arranged linearly in the longitudinal direction but are bent to some extent, it is important to keep the distance between draws as short as possible in close drawing in order to draw each fiber effectively. It is. The amount of heat required for proximity stretching is usually supplied by heating the roll to be stretched, and at the stretching point, heating with hot air or infrared rays is used supplementarily. Also,
Hot water, steam, etc. can also be used.

As described above, the stretching cylinder 211, the pressing rubber roll 213, and the take-off nip roll 214a,
Reference numeral 214b constitutes a stretching unit. Here, this stretching unit will be described in more detail with reference to FIG.

The stretching cylinder 211 is heated to an appropriate stretching temperature. For example, if the material of the web 52 is polypropylene, the temperature is 110 ° C, and if the material of the web 52 is polyester, the temperature is 85 ° C.
The web 52 adheres to the stretching cylinder 211 by the pressing rubber roll 213, and if the degree of the adhesion is appropriate, the stretching point becomes straight in the width direction at the point b where the web 52 separates from the stretching cylinder 211, and ideal close stretching is performed. .
When the adhesion is weak, the stretching point shifts to the point a on the stretching cylinder 211 side, and becomes unstable. Also, if the adhesion is too strong, the stretching point fluctuates between the point b and the point c, which is also unstable. This adhesiveness can be changed by heating the pressing rubber roll 213 with an infrared heater or the like, or by changing the adhesiveness of the surface of the stretching cylinder 211, whereby the stretching point can be fixed near the point b. Note that these conditions change depending on the line speed, basis weight, and the like.
Therefore, in order to fix the stretching point to the point b, it is effective to blow hot air having a linear cross section on the point b by the hot air generator 215 as shown in FIG. )
It is also effective to heat the b-line with the infrared line heater 216 that condenses the light from the infrared heater linearly as described above.

The longitudinally stretched nonwoven fabric 5 obtained as described above
3 is further stretched in the longitudinal direction by a stretching device as shown in FIG. 5, for example. Hereinafter, the stretching process of the nonwoven fabric will be described with reference to FIG. Note that the stretching device shown in FIG. 5 may be supplied with the longitudinally stretched nonwoven fabric 53 obtained by the device shown in FIG. 3 or the web 51 before stretching. Is simply represented as a web 54.

The web 54 includes nip rolls 301a,
Introduced by 01b into a stretching device, preheated by a preheating roll 302, and guided as a web 55 to a stretching roll 303. A nip rubber roll 304 is arranged to face the stretching roll 303, and the web 56 is stretched in the longitudinal direction between the stretching roll 303 and the stretching roll 305. The distance between the stretching is the stretching roller 303 of the first stage and the nip roll 304.
, And the travel distance PQ of the web determined by the nip point Q between the second-stage stretching roll 305 and the nip roll 306, between which the web 56 is stretched.

When multi-stage stretching by this apparatus is necessary, stretching is further performed between the stretching rolls 305 and 307. The inter-stretch distance in this case is the travel distance QR of the web 57 determined by the point Q and the nip point R of the stretch roll 307 and the nip roll 308. If heat treatment is required after the longitudinal stretching, the web 58 can be heat-treated with the heat treatment roll 309. The web 58 is taken up by the nip rolls 310a and 310b, and is obtained as a stretched web 59.

As described above, for the longitudinal stretching of the nonwoven fabric, an apparatus having a distance as short as possible is suitable. As shown in FIG. 5, by providing nip rolls 304, 306, and 308 for each of the stretching rolls 303, 305, and 307, the stretching point is fixed and the stretching is stabilized. Will be possible. Nip roll 30
When there is no 4 or the like, the stretching point moves to the preheating roll side from the point P, and not only the distance between stretching becomes long, but also the stretching point moves to cause stretching breakage. From the above principle, a web suitable for longitudinal stretching is preferably a web in which the fibers are arranged as vertically as possible. That is, since the fibers are long in the longitudinal direction, even if the distance between the stretchings is constant, the ratio of the fibers that are gripped at both ends increases, and the strength of the web after stretching is improved. In the device shown in FIG.
Heat for stretching is basically given by a heated roll, but hot air or infrared rays as shown in FIG. 4 can be used together. Further, the web can be covered with a cover between the traveling distances PQ and QR, and the inside thereof can be heated with steam. Even if the width of the web obtained by the apparatus shown in FIG. 3 is narrow, by stretching them in parallel and using the stretching apparatus shown in FIG. 5, a wide stretched web can be obtained.

Generally, in stretching a web, it is important to fix the stretching point. If the stretching point is not constant, the whole is not uniformly stretched, so that the stretching ratio cannot be increased, and portions having different stretching ratios are mixed in the stretched web, and sufficient web strength cannot be obtained. The width of the final product of the longitudinally stretched nonwoven fabric may be 1 m to 2 m or more. In the case of producing such a wide stretched nonwoven fabric, when the yarn is spun with a die having a narrow width and preliminarily stretched in the spun web production apparatus, proximity stretching is easy. By arranging the pre-stretched webs in parallel and further performing main stretching, a wide nonwoven fabric can be obtained. At that time, since the stretching ratio of the main stretching is low, the shrinkage of the width of the web is small. On the contrary, the overlap when arranging the pre-stretched webs in parallel is small, so that the overlap portion is not conspicuous. In addition, since the pre-stretched web has already been stretched in the longitudinal direction, in the main stretching, the distance between adjacent stretches may be relatively long.

In the multistage stretching, as the stretching means for the second and subsequent steps, not only proximity stretching but also various means used for ordinary web stretching can be applied. That is, various stretching methods such as roll stretching, hot water stretching, steam stretching, hot plate stretching and the like can be mentioned. Proximity drawing is not always necessary because the individual fibers have already been long in the length direction in the first drawing.

In the method for producing a longitudinally stretched nonwoven fabric, the draw ratio varies depending on the type of the polymer of the fiber constituting the web, the spinning means and the arrangement means of the web, and the like. However, regardless of which type or means is used, a stretching ratio that can achieve a high degree of orientation and high strength of the web is selected. The above stretching ratio is defined by the following formula using marks provided at predetermined intervals in the stretching direction of the web before stretching. Stretching ratio = [length between marks after stretching] / [length between marks before stretching] This stretching ratio does not necessarily mean the stretching ratio of the fiber here, as in the case of stretching of ordinary long fiber filament yarn. do not do.

Next, an example of a method for producing a nonwoven fabric by a spunbond method will be described with reference to FIG. FIG. 6 is a schematic configuration diagram of an example of a spinning device using a spunbond method in a narrow sense. In FIG. 6, the same components as those in FIG. 3 are described with the same reference numerals as in FIG.

In the SB spinning, a large number of fibers 222 spun from a spunbond die 221 having a large number of spinning holes are sucked by an air 224 by an ejector 223 and conveyed by the air accelerated by a nozzle of the ejector 223. 207 are integrated. As shown in the figure, a heat insulating wall 226 is provided below the spun bond die 221, a heater 227 is provided therein, and the flow of the spun fiber 222 is accompanied by heating air 228 heated to a temperature equal to or higher than the melting point, and the heat is immediately below the nozzle. Fiber 22
2 is not allowed to cool.

The fiber 222 is connected to the ejector 223
Immediately before entering, the ejector 223 is cooled by air containing mist-like moisture from the spray nozzle 208.
It is led to. Without the spray nozzle 208, the fibers 222 would fuse together within the ejector 223.
Note that, instead of the spray nozzle 208, it is also possible to cause the air 224 to contain mist-like water in the ejector 223.

The direction of the fiber 222 accelerated by the ejector 223 is changed by a barrier plate 229 which is inclined and installed on the loading surface of the conveyor 207, and is further sucked by the negative pressure suction nozzle 210, and the fiber shown in FIG. Similarly, it is accumulated on the inclined conveyor 207. Thereby, the arrangement of the fibers 222 is improved. In FIG. 6, the ejector 223 is installed vertically, but the outflow direction of the ejector 223 may be inclined.

The heat retaining wall 226 just below the nozzle of the spun bond die 221 shown in FIG. 6 is an introduction path of the heated air 228 heated by the heater 227, and functions as a heat retaining cylinder. However, as another method to keep the temperature just below the nozzle high,
It is also possible to directly heat directly below the nozzle with an infrared lamp or the like. In any case, by maintaining the temperature immediately below the nozzle at a high temperature, the molecular orientation of the fiber 222 is small even if the diameter of the fiber 222 is reduced by the draft. By raising the temperature of the heating air 228 shown in FIG. 6 higher than the spinning temperature (die temperature) of the fiber 22 by 80 ° C. or more, more desirably by 120 ° C. or more, the molecular orientation of the fiber 222 decreases, and the subsequent stretchability Is improved.

Although the meltblowing method and the spunbonding method have been described as typical production methods of the nonwoven fabric, the production method of the longitudinally stretched nonwoven fabric used in the present embodiment is not limited to these.

(1b) Step of producing reticulated film As described above, the reticulated film is formed by slitting the raw film starting from the raw film made of a thermoplastic elastomer, stretching the raw film in the lateral direction, and heating it. It is manufactured by extinguishing the restoring force. As the raw film, a general film, for example, a film formed by a T-die method, a film formed by cutting a tubular film, and the like are used.

First, the formation of a slit in the original film can be performed by, for example, an apparatus shown in FIG. In FIG. 7, the film 9 is guided onto the rotating roller 402 at a room temperature or after being preheated, passing between the nip rollers 401 and 401 ′. A cutter 403 in which triangular blades 403a each having a cutting edge on the oblique side are arranged in a line radially is fixed to the peripheral surface of the rotating roller 402, for example, as shown in FIG. The adjacent cutters 403 are arranged such that the positions of the triangular blades 403a are shifted from each other by a half pitch of the arrangement pitch of the triangular blades 403a.

The surface speed of the rotating roller 402 is faster than the speed at which the film 9 is supplied by the nip rollers 401 and 401 ', and the cutter 403 cuts the film 9 under tension. As a result, as shown in FIG. 10A, horizontal slits 9a are formed in the film 9 in a staggered pattern. The film 9 having the slit 9a formed after passing through the rotating roller 402 is taken up by the nip rollers 404 and 404 'and sent to the next step. The nip roller 4
The take-up speed of the film 9 by 04, 404 'is faster than the peripheral speed of the cutting edge of the cutter 403. This makes it easier for the cutting edge of the cutter 403 to come off the film 9.

As described above, the slit 9 is formed in the film 9.
Once a has been formed, the film 9 is then stretched laterally.

FIG. 9 is a schematic perspective view of an example of an apparatus suitable for widening a film in the horizontal direction.

As shown in FIG. 9, the film 9 having the slit formed thereon is guided to two pulleys 411 and 411 ′ via a turn roll 410. Two pulleys 411,
411 ′ is arranged so as to have a trajectory extending from upstream to downstream with respect to the transport direction of the film 9,
The film 9 is guided to its narrowest point.
Endless belts (or ropes) 412, 412 'are stretched along the tracks of the pulleys 411, 411'.
The film 9 guided to the pulleys 411 and 411 ′ is sent while being sandwiched between both ends in the width direction by the pulleys 411 and 411 ′ and the endless belts 412 and 412 ′.
Due to the trajectory made by 1 ', it is stretched laterally. Then, the film 9 stretched in the horizontal direction is
The belt 412 at the widest point of the track of 1, 411 ',
412 'and is taken off via a turn roll 414.

The flared wide portion is covered by the chamber 415 and is heated by hot air, a warm bath, infrared rays, or the like. Here, the film 9 is heated to a temperature equal to or higher than the flow start temperature of the material, and the restoring force has disappeared before the film 9 is separated from the belts 412, 412 '. As a result, turn roll 41
After the film 9 is taken out through the film 4, the film 9 keeps the widened width, and as shown in FIG.
Is formed on the reticulated film 12.

Although an example in which a slit is formed in a raw film of a film by using a cutter has been described above, the method of forming a slit in the film is not limited to this. For example, Japanese Patent Application Laid-Open No. Hei 5-228669. The slit may be formed by irradiating a film with a laser beam, infrared light, or ultraviolet light as disclosed in Japanese Patent Application Laid-Open No. H10-209,036.

(1c) Joining Step The joining between the longitudinally stretched nonwoven fabric and the reticulated film can be performed by a calendar roll method, an emboss roll method, or the like.

FIG. 11 shows an example of an apparatus for joining a longitudinally stretched nonwoven fabric and a reticulated film. In the apparatus shown in FIG. 11, a longitudinally stretched nonwoven fabric 1 in which fibers are arranged in a longitudinal direction and stretched is used.
1 and a reticulated film 1 provided with a laterally long opening
2 is a pinch roll 50 in a state of being overlapped with each other.
After passing through 1, 502 ', it is supplied to the heating cylinder 503 and is thermocompression-bonded between the heating cylinder 503 and the thermocompression roll 504 to form the composite sheet 10.

The most efficient and inexpensive method is to use heat to join the longitudinally stretched nonwoven fabric 11 and the reticulated film 12. However, depending on the kind of the elastomer, it is also possible to interpose a generally used adhesive third layer such as EVA between the longitudinally stretched nonwoven fabric and the reticulated film to join them together. In this case,
By providing a glue bath on one of the pinch rolls 501 and 501 ′ and supplying an adhesive by the glue bath, the nonwoven fabric 11 and the reticulated film 12 can be joined.

For bonding the nonwoven fabric 11 and the reticulated film 12, in addition to the above-mentioned methods, ultrasonic bonding, high-frequency bonding, or a physical bonding method such as needle punch or water jet can be used. .

As described above, in the present embodiment, the elastomer web and the nonwoven fabric made of inelastic fibers are joined in a state where the restoring force of the thermoplastic elastomer web is extinguished by stretching and heating. Thus, by expanding the elastomer web, the opening of the elastomer web is enlarged, and a composite sheet having sufficient air permeability and moisture permeability can be obtained. The stretch ratio of the elastomer web is usually 2 times, desirably 3 times or more.

Further, by stretching the elastomer web, the elastic web becomes thinner, the strands constituting the net become thinner, and the flexibility increases, so that the stretchable composite sheet is particularly preferable for applications such as clothing. Becomes Stretching means that the thickness of the raw web of the elastomer web may be increased by the stretching ratio. Since it is difficult to produce a thin web with a uniform thickness using a thermoplastic elastomer, a raw web of an elastomer web can be easily produced by reducing the thickness of the web by stretching.

Further, in the present embodiment, the elastomer web is stretched in the lateral direction, but by this, it is possible to produce a product having a narrow material width to a wide width. Therefore, the stretching of the elastomer web in the transverse direction is low in equipment cost,
It is suitable for producing wide webs using thermoplastic elastomers having poor moldability.

(Second Embodiment) FIG. 12 is a plan view of a composite sheet according to a second embodiment of the present invention. FIG.
Is joined to a reticulated film 22 made of a thermoplastic elastomer having a large number of longitudinally long openings 22a provided on one surface of a stretched nonwoven fabric 21 in which fibers 21a are arranged in a substantially horizontal direction. It was done.

The composite sheet 20 of this embodiment is made of the nonwoven fabric 2
1 and the reticulated film 22 in a relationship between the length and width of the composite sheet described in the first embodiment. The relationship is reversed. That is, the composite sheet 20 of the present embodiment
Is stretchable in the vertical direction, but hardly stretches in the horizontal direction and has excellent dimensional stability. In addition, it is the same as the first embodiment in that it has air permeability (moisture permeability), high utilization efficiency of the elastomer, and the like. The same material and elastomer as those of the first embodiment can be used for the nonwoven fabric 11.

Next, an example of a method for manufacturing the composite sheet 20 of the present embodiment will be described with reference to the process chart of FIG.

In the present embodiment, similarly to the first embodiment, the steps of manufacturing the composite sheet 20 are roughly divided into a step of manufacturing the nonwoven fabric 22, a step of manufacturing the elastomer web, and a step of joining these. Consists of

In the step of manufacturing the nonwoven fabric 22, first, a web in which fibers are arranged in a substantially horizontal direction is obtained by using an appropriate spinning device (step 111). Next, the web is stretched in the fiber arrangement direction (step 11).
2), a non-woven fabric 22 stretched in the lateral direction is obtained.

On the other hand, in the step of producing an elastomeric web, first, a longitudinally long slit is formed in a film made of the elastomer (step 113). Next, the film in which the slit is formed is stretched in the longitudinal direction, and heated at a temperature equal to or higher than the flow start temperature of the material of the film (step 114). As a result, the restoring force of the film disappears. Next, the film on which the slit is formed is widened (step 115). At this time, the film is heated at a temperature equal to or higher than the flow start temperature of the material. As a result, the restoring force of the film disappears, and the reticulated film 22 provided with the vertically long openings 22a as shown in FIG.
Is obtained.

Then, the nonwoven fabric 21 obtained as described above and the reticulated film 22 are joined so that their respective positions in the width direction are matched (step 116), and the composite sheet 20 is obtained.

Hereinafter, each of the above-described steps will be described in detail. (2a) Non-woven fabric manufacturing process As a non-woven fabric manufacturing method, for example, Japanese Patent Publication No. 3-36948
JP, JP-A-7-6126, and Japanese Patent No. 26122
No. 03, republished patent WO9617121, Japanese Patent Application Laid-Open No. 10-204764, and the like. Also, as a prior application, Japanese Patent Application No. Hei 10-34242.
There is also a method described in the issue.

In this embodiment, a nonwoven fabric in which fibers are arranged and stretched in a substantially horizontal direction is used, and therefore, an apparatus different from that of the first embodiment is used for manufacturing the nonwoven fabric.

FIG. 14 is a view showing an apparatus suitable for spinning fibers having a large number of components arranged in the horizontal direction. FIG. 14A is a view of the ejection head viewed from below, and FIG. (B) is a side sectional view of the ejection head, and (C) is a sectional view of the ejection head as viewed from the front.

In FIG. 14, an injection port 231 discharges a melt of the resin constituting the nonwoven fabric. Air holes (233-1, 233-33) are formed around the injection port 231.
2, 233-3,..., Usually 3 to 8). These air holes are provided slightly obliquely so that the air intersects the fiber 232 discharged from the injection port 231 within several centimeters to several tens of centimeters from the injection port 231. Thereby, the fiber 232 is rotated in a spiral shape.

Below the ejection head, a screen mesh 235 is arranged. Air holes 233-1, 23
3-2, ..., two other air holes 23
4, 234 ′ are provided so as to be parallel to the moving direction of the screen mesh 235 and to have the air jetting directions facing each other. The air jetted from each of the air holes 234 and 234 ′ collides with each other and spreads in a direction perpendicular to the moving direction of the screen mesh 235, and the fibers 232 rotated by the force of the air move the screen mesh 235. Accumulate on the screen mesh 235 while being scattered at right angles to the direction. Thereby, the fibers 23 are formed on the screen mesh 235 in a form in which the components arranged in the width direction of the nonwoven fabric to be formed are increased.
2 are accumulated, and a non-woven fabric mainly composed of a horizontal arrangement is obtained.

Since the dispersion width of the fiber by one injection port 231 is usually in the range of 100 to 300 mm, this injection port 231 is selected according to the width of the target nonwoven fabric.
May be provided in plurality. When it is desired to increase the density of the fibers 232 without lowering the transport speed of the nonwoven fabric, the jet heads may be provided in multiple stages in the transport direction of the nonwoven fabric.

In order to minimize the variation in the density of the fiber 232 in the longitudinal direction and to reduce the molecular orientation of the fiber 232 as much as possible, the temperature of the air injected from each air hole should be several tens of degrees higher than the melting point of the fiber 232. It is preferable to make the height higher. Further, depending on the type of the polymer constituting the fiber 232, only the air jetted from one of the two types of air holes may be heated.

[0103] The nonwoven fabric obtained as described above is stretched in the transverse direction to be a horizontally stretched nonwoven fabric. The stretching of the nonwoven fabric in the lateral direction can be performed using the apparatus shown in FIG. 9 as it is. That is, when a nonwoven fabric is supplied to the apparatus shown in FIG. 9 instead of a film, a laterally stretched nonwoven fabric can be obtained. (2b) Manufacturing Process of Reticulated Film The reticulated film 22 used in the present embodiment starts from a film made of a thermoplastic elastomer, forms slits in the film, and stretches in the longitudinal direction, as described above. Manufactured by widening.

First, a longitudinal slit is formed in the film. Similar to the first embodiment, the slit can be formed by passing the film over a rotating roller provided with a cutter on the peripheral surface. In this embodiment, since a vertically long slit is formed, the cutter is attached in a direction orthogonal to the first embodiment.

Next, the film is stretched in the vertical direction.
For stretching the film in the longitudinal direction, a device similar to that used for longitudinal stretching of the nonwoven fabric in the first embodiment or a general longitudinal stretching device can be used. in this case,
When the film is stretched in the longitudinal direction, the width of the film is reduced in accordance with the stretching magnification, and a slit is opened to that extent, so that the film becomes net-like. At this time, the film is heated to a temperature equal to or higher than the flow start temperature, and the restoring force is extinguished.

Next, the film on which the slit has been formed is widened. In this step, the same apparatus as used for widening the film in the first embodiment, that is, the apparatus shown in FIG. 11 is used. The film can be widened. At this time, the film is heated at a temperature equal to or higher than the flow start temperature of the material, and the restoring force disappears, whereby a reticulated film 22 having a vertically long opening 22a as shown in FIG. 12 is obtained. The magnification at this time is smaller than the magnification at the time of stretching in the vertical direction. That is, the film is relatively stretched in the longitudinal direction.

Here, an example has been described in which a vertically long slit is formed in the film, the film is stretched in the vertical direction, and then the film is widened. However, as shown in FIG. 15, the film is first stretched in the vertical direction (step 113 '). ) To form a vertical slit (step 114 ′), and then widen the slit-formed film in the horizontal direction (step 11 ′).
5 ').

(2c) Joining Step The joining between the nonwoven fabric in which the fibers are arranged in the horizontal direction and stretched and the reticulated film having the vertically long openings can be carried out in the same manner as in the first embodiment.

(Other Embodiments) The method and apparatus suitable for producing the composite sheet of the present invention have been described above with reference to some typical examples. They can be appropriately combined according to the use and configuration of the composite sheet.

Further, the structure of the composite sheet is not limited to those shown in the two representative embodiments described above, and various structures can be adopted. Hereinafter, other embodiments of the present invention to which the above-described method and apparatus are applied will be described.

<Example of Opening Pattern of Elastomer Web> In the first and second embodiments, an example was shown in which a film having a net-like opening pattern was used as the elastomer web, but the opening pattern is limited to a net-like shape. Not something. However, from the viewpoint of the use efficiency of the elastomer, it is preferable that the amount of the elastomer used in the direction orthogonal to the direction in which the composite sheet expands and contracts is smaller than the direction in which the composite sheet expands and contracts.
The following are some examples of preferred opening patterns. The example shown below is an example of a composite sheet that expands and contracts in the horizontal direction, that is, a film that is bonded to a stretched nonwoven fabric in which fibers are arranged in the vertical direction. Therefore, in the case of a composite sheet that expands and contracts in the vertical direction, the following pattern is a pattern obtained by rotating the pattern by 90 degrees.

The example shown in FIG. 16 is an example of a ladder-like film 31 having a ladder-like opening pattern. FIG.
As shown in (a), the opening 31a is formed in the ladder-like film 3.
1 has a length that is substantially the same as the width of the opening 3.
1 a are arranged in the longitudinal direction of the ladder-like film 31. In order to manufacture such a ladder-like film 31, as shown in FIG. 16 (b), a slit 30a covering almost the entire area in the width direction of the film 30 serving as the raw film is formed.
May be formed at intervals in the vertical direction.

The example shown in FIG. 17 is an example of a branching film 41 having an opening pattern in which a trunk portion 41b and a branch portion 41c having different thicknesses cross each other. As shown in FIG. 17A, the branching film 41 has a trunk portion 41b substantially parallel to the lateral direction, and a branch portion 41c which is thinner than the trunk portion 41b and obliquely intersects with the trunk portion 41b. The opening 41a has a trunk portion 41b and a branch portion 41c.
And are surrounded by In order to manufacture such a branched film 41, as shown in FIG. 17B, a stepwise slit 40a may be formed in the film 40 as a raw film in a lateral direction.

<Example of Using Nonwoven Fabric as Elastomer Web> The elastomer web is not limited to a film having openings, and a nonwoven fabric formed of a thermoplastic elastomer can also be used.

FIGS. 18 and 19 show an example of a production process of a composite sheet using a thermoplastic elastomer nonwoven fabric.

In the example shown in FIG. 18, the fiber spinning step (step 12
1) and the longitudinal stretching step (step 122) are the same as in the first embodiment. On the other hand, in the step of producing an elastomer nonwoven fabric, first, a nonwoven fabric in which elastomer fibers are arranged in a lateral direction is formed (step 123), and then it is stretched in a lateral direction (step 124). (Step 125). Then, the non-elastic nonwoven fabric and the elastomer nonwoven fabric are joined (step 126) to produce a composite sheet.

The composite sheet thus obtained is shown in FIG.
0 is shown. The composite sheet 50 shown in FIG. 20 has an inelastic nonwoven fabric 51 in which inelastic fibers are arranged in a substantially vertical direction.
And an elastomeric nonwoven fabric 52 in which elastomer fibers are arranged in a substantially horizontal direction.

The example shown in FIG. 19 is an example in which the fiber arrangement of the inelastic non-woven fabric and the elastomer non-woven fabric is reversed from that shown in FIG. In the example shown in FIG. 19, the fiber spinning step (step 131) and the transverse stretching step (step 132) of the step of manufacturing an inelastic nonwoven fabric are the second steps.
This is the same as the embodiment. On the other hand, in the step of manufacturing an elastomer nonwoven fabric, first, a nonwoven fabric in which elastomer fibers are arranged in a vertical direction is formed (step 13).
3) and then stretch it vertically (step 1)
34), heating to a temperature equal to or higher than the flow start temperature of the elastomer (step 135). Then, the non-elastic nonwoven fabric and the elastomer nonwoven fabric are joined (step 136) to produce a composite sheet.

Elastomeric nonwoven fabrics are prepared by a conventional melt blow method or a spunbond method (Japanese Patent Laid-Open No. 61-55).
249, etc.) or the prior invention by the present inventors (JP-A-2-242960, JP-A-10-204).
No. 767) can be used, but the present invention is not limited thereto. The stretching of the elastomeric nonwoven fabric and the joining between the inelastic nonwoven fabric and the elastomeric nonwoven fabric can be performed using the means described in the first embodiment or the second embodiment.

When the elastomer web is made of a nonwoven fabric, the openings for air permeability and the like are formed by the gaps between the fibers of the elastomer, so that the openings are fine. However, even if the opening is fine, the opening is enlarged in the subsequent stretching step, so that the air permeability and the moisture permeability are not impaired. In addition, the arrangement direction of the elastomer fibers in the case where the elastomer web is formed of a non-woven fabric is, from the viewpoint of the efficiency of use of the elastomer in the expansion and contraction direction of the composite sheet, considering the shape of the opening after being expanded in the stretching step. It is preferable that the direction be perpendicular to the direction in which the inelastic fibers of the nonwoven fabric are arranged. In other words, in the stretching step of the elastomeric nonwoven fabric, it is preferable to stretch the elastomeric web in the arrangement direction of the elastomeric fibers. Thereby, the opening of the nonwoven fabric made of the elastomer fiber can be easily made a long opening in one direction. Further, even in the case of an elastomeric nonwoven fabric, a slit may be formed in the elastomeric nonwoven fabric to further add an opening as in the case of a film.

As described above, even when the elastomer web is formed of a nonwoven fabric, the expansion (including the heat treatment for eliminating the extension stress) and the bonding with the nonwoven fabric made of the inelastic fiber are performed by using the fibers. According to the arrangement direction, the above-described various devices can be appropriately selected and used, and the above-described method can be used.

When the arrangement direction of the nonwoven fabric made of inelastic fiber and the arrangement direction of the elastomer fiber are equal, as shown in FIG. If the nonwoven fabric 81 made of an elastomer is supplied from a right angle direction, it is possible to obtain a composite sheet in which the arrangement direction of the inelastic fibers and the arrangement direction of the elastomer fibers are orthogonal. The width of the composite sheet obtained by this method is the width of the nonwoven. Therefore, when the nonwoven fabric 81 made of the elastomer fiber is supplied, the nonwoven fabric 81 is cut in accordance with the width of the nonwoven fabric 71 made of the inelastic fiber, and is continuously cut so as to minimize overlap with the previously supplied nonwoven fabric 81a. Layer on the non-woven fabric.

The elastomeric web may be in the form of a net or a knitted or woven fabric made of a thermoplastic elastomeric yarn, in addition to the above-mentioned film or nonwoven fabric having openings.

As described above, the present invention provides a composite sheet having elasticity in one direction and having air permeability and moisture permeability, and a method for producing the same. In particular, elastic bandages, supporters, clothing cuffs, elastic tape, stretch belts, brassiere straps, belly band, pregnant women, gloves and socks to prevent fraying, diapers and incontinence pads, etc. Clothing,
Suitable for medical products.

According to the present invention, it is possible to efficiently exhibit elasticity while having air permeability and moisture permeability, and to produce a composite sheet by a simple and efficient molding method. The composite sheet is excellent in mass productivity.

The non-elastic fiber non-woven fabric used in the present invention is a non-woven fabric in which the fibers are arranged in one direction and stretched, and is suitable for increasing the elongation at break in the direction perpendicular to the direction in which the fibers are arranged. Even if the basis weight of the nonwoven fabric is small, its elongation characteristics are not impaired. Therefore, the amount of the nonwoven fabric can be reduced, and a sheet with a low cost can be provided.

[0127]

As described above, according to the present invention, a nonwoven fabric in which inelastic fibers are arranged in one direction is bonded to a web made of a thermoplastic elastomer having air holes, thereby forming the fibers in the arrangement direction. However, it is possible to provide a composite sheet that has little or no deformation, but has a stretchable property that greatly expands and contracts in a direction perpendicular to it, and has air permeability. In addition, even if the basis weight of the nonwoven fabric and the amount of the thermoplastic elastomer used are small, the above-mentioned elastic properties are not impaired, so that an inexpensive composite sheet can be obtained.
Furthermore, according to the method for manufacturing a composite sheet of the present invention, the above-described composite sheet of the present invention can be easily and efficiently manufactured.

[Brief description of the drawings]

FIG. 1 is a plan view of a composite sheet according to a first embodiment of the present invention.

FIG. 2 is a process chart showing an example of a method for producing the composite sheet shown in FIG.

FIG. 3 is a schematic perspective view of an example of an apparatus for spinning and drawing a fiber by a melt blow method.

FIG. 4 is a diagram illustrating the proximity stretching unit shown in FIG. 3 in detail.

FIG. 5 is a schematic configuration diagram of an example of a stretching device that stretches a web in a longitudinal direction.

FIG. 6 is a schematic cross-sectional configuration diagram of an example of an apparatus for preventing fibers by a spun bond method.

FIG. 7 is a schematic configuration diagram of an example of an apparatus for forming a slit in a film.

FIG. 8 is a front view of the cutter shown in FIG. 7;

FIG. 9 is a schematic perspective view of an example of an apparatus for stretching a film (web) in a lateral direction.

FIG. 10 is a plan view of the reticulated film shown in FIG. 1 before stretching and after stretching in the lateral direction.

FIG. 11 is a schematic view of an example of an apparatus for joining a nonwoven fabric made of inelastic fiber and an elastomer web.

FIG. 12 is a plan view of a composite sheet according to a second embodiment of the present invention.

13 is a process chart showing an example of a method for manufacturing the composite sheet shown in FIG.

FIG. 14 is a view showing an apparatus for spinning fibers having a large number of components arranged in a horizontal direction, which is used for manufacturing the nonwoven fabric shown in FIG. 12.

15 is a process chart showing another example of the method for manufacturing the composite sheet shown in FIG.

FIG. 16 is a plan view of another example of the opening pattern of the film used for the composite sheet according to the present invention, before and after stretching.

FIG. 17 is a plan view of still another example of the opening pattern of the film used in the composite sheet of the present invention after stretching and before stretching.

FIG. 18 is a process chart showing an example of a method for producing a composite sheet when a thermoplastic elastomer nonwoven fabric is used.

FIG. 19 is a process chart showing another example of a method for producing a composite sheet when a thermoplastic elastomer nonwoven fabric is used.

FIG. 20 is a schematic perspective view of the composite sheet manufactured in the step shown in FIG.

FIG. 21 is a view for explaining a joining method in a case where nonwoven fabrics in which fibers are arranged in a longitudinal direction are joined with the fibers orthogonal to each other.

[Explanation of symbols]

9, 30, 40 Film 9a, 30a, 40a Slit 10, 20, 50 Composite sheet 11, 21 Nonwoven fabric 11a, 21a Fiber 12, 22 Reticulated film 12a, 22a, 31a, 41a Opening 31 Laddered film 41 Branching Film 41b Trunk 41c Branch 51 Non-elastic non-woven fabric 52 Elastomeric non-woven fabric 201 Melt blow die 203 Nozzle 207 Conveyor 210 Negative pressure suction nozzle 211 Stretching cylinder 212, 213 Pressing rubber roll 214a, 214b Take-off nip roll 231 Injection port 233-1 to 233-6, 234, 234 'Air hole 235 Screen mesh 302 Heating roll 303, 305, 307 Stretching roll 309 Heat treatment roll 401, 401', 404, 404 'Nip roll 402 Rotation roll Roller 403 Cutter 403a Triangular blade 410, 414 Turn roll 411, 411 'Extension pulley 412, 413 Endless belt 415 Chamber 501, 502' Pinch roll 503 Heating cylinder 504 Thermocompression roll

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kenichi Kobayashi 3-35-4 Hanakoganei, Kodaira-shi, Tokyo F-term (reference) 4F100 AL09B AT00B BA02 BA22 DC12 DC12B DC13B DG01 DG01B DG15 DG15A EJ37A EJ42 EJ90B GB66 GB72 GB87 JB16B JD02 JD04 JK08 4L047 BD02 CA02 CA10 CB01 CB08 CB10 CC03 CC04 CC05

Claims (9)

[Claims] 1. An inelastic fiber is arranged in one direction,
The elongation in the direction perpendicular to the arrangement direction of the fibers is 10
0% or more of a nonwoven fabric, and a thermoplastic elastomer bonded to the nonwoven fabric, the web having ventilation holes, wherein the web is stretched in a direction perpendicular to the direction in which the inelastic fibers are arranged. A composite sheet having a web that has lost restoring force by being maintained at a temperature equal to or higher than the flow start temperature of a plastic elastomer. 2. The composite sheet according to claim 1, wherein the nonwoven fabric is a nonwoven fabric in which fibers are stretched in a direction in which the fibers are arranged. 3. The composite sheet according to claim 1, wherein the web is a film provided with an opening for ventilation. 4. The composite sheet according to claim 3, wherein the opening has a shape elongated in a direction perpendicular to a direction in which the inelastic fibers are arranged. 5. The composite sheet according to claim 1, wherein the web is a nonwoven fabric made of fibers of a thermoplastic elastomer. 6. The composite sheet according to claim 5, wherein an arrangement direction of the fibers of the thermoplastic elastomer is a direction perpendicular to an arrangement direction of the inelastic fibers. 7. A step of forming a nonwoven fabric in which inelastic fibers are arranged in one direction, a step of forming a web made of a thermoplastic elastomer having ventilation holes, and a step of extending the web in one direction. Heating the stretched web to a temperature equal to or higher than the flow start temperature of the thermoplastic elastomer to eliminate the restoring force of the web; and the nonwoven fabric and the web having lost the restoring force,
A method for producing a composite sheet, comprising: a step of joining the inelastic fibers so that an arrangement direction of the inelastic fibers and a stretching direction of the web are perpendicular. 8. The composite sheet according to claim 8, wherein a film made of a thermoplastic elastomer is used as the web, and the step of forming the web includes a step of forming a slit serving as the ventilation hole in the film. Manufacturing method. 9. The step of forming the slit includes forming a slit that is long in a direction in which the web extends.
3. The method for producing a composite sheet according to item 1.