JP2003175558A - Laminated sheet and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated sheet which has both moisture permeability and water stop properties or stretchability, while holding the cloth touch that a nonwoven fabric has inherently, and which is suitable as a hygienic material. <P>SOLUTION: A resin film constituted of at least two layers is joined onto the nonwoven fabric to form a laminate. A part of the resin film layer on the side in contact with the nonwoven fabric layer penetrates into a gap in fibers of the nonwoven fabric and integrates therewith. At least one of the resin film layers is formed of a resin containing an inorganic filler and an ethylene α-olefin copolymer is used preferably as the resin. It is desirable that the resin has physical properties of the density 0.870-0.935, MFR 1-90 (g/10 min) and the melt tension 0.5-10 (g). Moreover the laminate is desirably oriented in 1.1-5 times at least in one direction thereof. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated sheet in which a non-woven fabric and a resin film are bonded to each other to maintain a cross-like feel, and a method for producing the same. More specifically, the present invention relates to a laminated sheet having breathability and water stopping properties while maintaining a cross-like feel, or a laminated sheet having good stretchability, and a method for producing the same.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION A two-layer sheet in which a thermoplastic resin film is laminated on a non-woven fabric is manufactured, paying attention to the physical properties of the sheet, packaging materials, sanitary materials such as disposable diapers and sanitary products,
It is used as a material in a wide range of industrial fields such as civil engineering and construction materials such as waterproof sheets.

The purpose of using the two-layer sheet is to utilize both the characteristics of the nonwoven fabric and the characteristics of the resin film. The extrusion lamination method, which is generally excellent in production stability and economy, is widely used for manufacturing a two-layer sheet because it is suitable as a large-lot production method. However, when a thermoplastic resin is extruded and laminated onto the surface of a non-woven fabric with many voids, the molten resin easily penetrates deeply into the fiber gaps, and the cross-like feel of the non-woven fabric is lost, and the elasticity of the resin film decreases. Since it is easy and pinholes are easily generated in the resin film layer, the characteristics of each layer are not always exhibited as they are, and further improvement of physical properties is required by improving the manufacturing method.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention, therefore, to provide a laminated sheet having moisture permeability and water stopping properties while maintaining the cloth-like touch inherent in a nonwoven fabric, and a method for producing the same. Another object of the present invention is to provide a laminated sheet which retains the cloth-like touch inherent to the nonwoven fabric and also has the elasticity inherent to the resin film, and a method for producing the same.

[0005]

Means for Solving the Problems That is, the present invention is a laminate in which a resin film comprising at least two layers is bonded onto a non-woven fabric, and the resin film layer on the side in contact with the non-woven fabric has a part of the fibers of the non-woven fabric. It relates to a laminated sheet that penetrates the interstices.

In a preferred embodiment of the laminated sheet, the laminated body is stretched in at least one direction, has a water pressure resistance of 1000 (mmH ₂ O) or more, and has a water vapor transmission rate of 1000 to 6000 (g / g). The sheet may be m ² · 24 hr).

As another preferred embodiment of the laminated sheet, the laminated body has an elongation at break of 200 in the transverse direction.
〜1000%, and tensile strength in the transverse direction of 5-30 (N /
cm).

The above-mentioned non-woven fabric layer has a basis weight of 10 to 60 (g / m ² ) and is a spunbonded non-woven fabric or a laminated non-woven fabric of the spunbonded non-woven fabric and a melt-blown non-woven fabric. It is desirable that each

Further, the resin film layer is
Overall basis weight is 10-60 (g / m ^Two), Of which
The basis weight of the resin film layer on the side in contact with the non-woven fabric layer is
5-50 (g / m^Two) Is desirable. Also the tree
As the resin forming the oil film layer, at least the resin
One layer may contain an inorganic filler, and in that case,
The content is preferably in the range of 20 to 70 (% by weight). This
Una resin film layer is made of polyolefin
Is desirable, especially for ethylene / α-olefin
Polyolefin containing polymers are preferred. Contact the non-woven fabric layer
The resin film layer on the side to be formed has a density of 0.870 to 0.93.
5 (g / cm^Three), Melt flow rate 1 to 90 (g /
10 minutes), and melt tension 0.5 to 10 (g)
Preferably, it is formed from a polyolefin.

Such a laminate is preferably stretched 1.1 to 5 times in at least one direction.

According to the present invention, the molten resin is extruded on the surface of the non-woven fabric from a T-die at a die temperature of 200 to 280 ° C. into a film form, and then a nip pressure of 5 to a gap between a pair of nip rolls and cooling rolls is used. 20 (kg / c
m ² ) in the first step of forming a two-layer laminate in which the non-woven fabric layer and the resin film layer are integrated, and further coating the same or different resin film layer on the resin film layer. And a second step of forming a laminated body by using the laminated sheet.

Further, according to the present invention, the same kind or different kinds of molten resin is extruded between the nonwoven fabric and the resin film from a T die at a die temperature of 200 to 280 ° C. into a film shape, and then a pair of nip rolls and a cooling roll. And a nip pressure of 5 to 20 (kg / cm ² ) to form a laminate in which the above three layers are integrated to form a laminated sheet.

Here, it is desirable that the supplied non-woven fabric is provided with a tension of 0.1 to 5 (kg / m) in the longitudinal direction. Further, at least one of the resin film layers may contain an inorganic filler, and the content in that case is preferably in the range of 20 to 70% by weight. Further, this production method may be added with a step of stretching the obtained laminate in at least one direction, in which case the stretching step may be performed by supplying the laminate to a gear stretching device. desirable.

Next, the preferred embodiments of the present invention will be described in two parts.

The first embodiment is a laminate in which a resin film composed of at least two layers is bonded onto a non-woven fabric,
The resin film layer is both formed of a resin containing an inorganic filler, and the resin film layer on the side in contact with the non-woven fabric is partly infiltrated into the fiber gap of the non-woven fabric.

The laminate is stretched in at least one direction and has a water pressure resistance of 1000 (mmH ₂ O).
Above, and the water vapor transmission rate is 1000 to 6000 (g / m
It is preferably ² · 24 hr).

[0017] Here, preferred thickness constitution of the laminated sheet, the nonwoven layer is 10~60 (g ^{/ m} 2), the resin film layer is 10~60 (g ^{/ m} 2), the side resin film contacting to the inner nonwoven fabric The layer is 5 to 50 (g / m ² ).

The preferred nonwoven fabric is a spunbond nonwoven fabric or a laminated nonwoven fabric of the spunbond nonwoven fabric and the meltblown nonwoven fabric. Both the nonwoven fabric and the resin film are preferably formed of polyolefin, and the density of the resin film layer on the side in contact with the nonwoven fabric is 0.870-0.
935 (g / cm ³ ), melt flow rate 1 to 90
(G / 10 minutes), and melt tension of 0.5 to 1
A resin having a physical property of 0 (g) is suitable. As an example, a polyolefin containing an ethylene / α-olefin copolymer can be mentioned. In addition, it is desirable that the resin forming the resin film layer contains 20 to 70 (% by weight) of the inorganic filler.

Also in this embodiment, the surface of the nonwoven fabric
Molten resin containing inorganic filler on top of T die from below die temperature
Extruded into a film at 200-280 ℃ and then nipped
In the gap between a pair of rolls consisting of a roll and a cooling roll,
Up pressure 5-20 (kg / cm ^Two) Under the conditions of
The first step of forming a solidified laminate, and further
Resin film containing inorganic filler on the resin film layer
A second step of coating the layers to form a laminate
A method of making a layered sheet is included. Here, the first step
Then, in the supplied non-woven fabric, 0.1-5 in the longitudinal direction.
It is preferable that a tension of (kg / m) is applied.

Here, after the second step, a third step of stretching the laminate in at least one direction may be added, and the stretching step is preferably performed using a gear stretching device. .

A second embodiment is a laminate in which a resin film composed of at least two layers is bonded onto a non-woven fabric,
The resin film layer on the side in contact with the non-woven fabric partially penetrates into the fiber gaps of the non-woven fabric, the elongation at break in the transverse direction of the laminate is 200 to 1000%, and the tensile strength in the transverse direction is 5 to 5.
It relates to a laminated sheet which is 30 (N / cm).

Here, the preferred thickness constitution of the laminated sheet is such that the nonwoven fabric layer is 10 to 60 (g / m ² ), the resin film layer is 30 to 60 (g / m ² ), of which the resin film on the side in contact with the nonwoven fabric. The layer is 5 to 40 (g / m ² ).

The preferred nonwoven fabric is a spunbond nonwoven fabric or a laminated nonwoven fabric of the spunbond nonwoven fabric and the meltblown nonwoven fabric. It is desirable that both the non-woven fabric and the resin film are formed of polyolefin, and the density of the resin film layer on the side in contact with the non-woven fabric is 0.870 to
0.935 (g / cm ³ ), melt flow rate of 1
90 (g / 10 minutes), and melt tension of 0.1
A resin having physical properties of 10 to 10 (g) is suitable. As an example, a polyolefin containing an ethylene / α-olefin copolymer can be mentioned. Further, of the resin film layers, at least one layer after the second layer is preferably formed of a resin containing 20 to 70% by weight of an inorganic filler.

Further, in this embodiment, the molten resin is applied on the surface of the non-woven fabric from the T die at a temperature below the die of 200 to 280.
With a nip pressure of 5 to 20 in the gap between a pair of rolls consisting of a cooling roll and a nip roll.
The first step of forming a laminated body by passing it under the condition of (kg / cm ² ), and the ^second step of coating a new resin film layer on the resin film layer to form a laminate. The laminate has a transverse elongation at break of 200 to 1000% and a transverse tensile strength of 5
It also includes a method for manufacturing a laminated sheet having a thickness of 30 (N / cm).

Here, in the first step, it is desirable that a tension of 0.1 to 5 (kg / m) is applied to the supplied nonwoven fabric in the longitudinal direction thereof. The second step is preferably carried out by an extrusion lamination method using the same resin as the resin laminated in the first step, and at least one of the resin film layers contains 20 to 70 wt% of an inorganic filler. %, It is desirable to be formed from a resin.

[0026]

DETAILED DESCRIPTION OF THE INVENTION Next, the laminated sheet of the present invention and the method for producing the same will be specifically described in order.

Laminated Sheet The laminated sheet according to the present invention comprises a nonwoven fabric and a resin film consisting of at least two layers, and a part of the resin film layer on the side in contact with the nonwoven fabric penetrates into the fiber gap of the nonwoven fabric. By doing so, a laminated body structure in which both layers are integrated is formed.

The thickness composition of each layer is defined as the weight per unit area,
In other words, the fabric weight of the non-woven fabric layer is preferred.
10-60 (g / m)^Two), More preferably 15-
40 (g / m^Two), The weight of the entire resin film layer is
10-60 (g / m) ^Two), More preferably 15
~ 55 (g / m^Two). Both layers have such a thickness configuration
Is sufficient mechanical strength as a normally used sheet.
It has a high degree of elasticity and is thin and flexible overall.
It has a smooth feel, and has good water resistance and breathability.
Good fit to other objects.

On the other hand, the resin film layer is formed of at least two layers, and the basis weight of the layer on the side in contact with the non-woven fabric is preferably 5 to 50 (g / m ² ), more preferably 5 to 35 (g). / M ² ), more preferably 10 to 25
(G / m ² ). When the total thickness of the resin film layer and the thickness ratio of each layer are within the above range, the flexibility and stretchability of the laminated sheet, and the texture, bulkiness, touch, softness and the like of the nonwoven fabric itself are expressed. The improved cross-like feel.

In the laminated sheet according to the present invention, it is important that the required thickness of the resin film layer is divided into two or more layers, and preferably the thickness of the first resin film layer on the side in contact with the non-woven fabric. Is preferably as thin as possible, and is adjusted to have a thickness substantially equal to or less than that of the resin film layers after the second layer. When the required thickness of the resin film layer is formed by only one layer, the obtained laminated sheet is hard, and a sheet having flexibility and a cross feeling is hardly obtained.

Nonwoven fabrics that can be used may be non-woven fabrics formed of short fibers, long fibers or continuous fibers, and the materials thereof include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and nylon 6, Polyamide such as 66 can be used, but is not particularly limited. In addition, it may be formed from a fiber in which polyethylene, polypropylene or the like is combined in a core-sheath or side-by-side shape. The bonding between the fibers may be heat bonding or an adhesive may be used.

Such a nonwoven fabric can be used regardless of whether it is produced by a dry method, a wet method, a spun bond method, or a melt blown method. In particular, the nonwoven fabric produced from polypropylene by the spunbond method, and the laminated nonwoven fabric of the nonwoven fabric produced by the spunbond method and the nonwoven fabric produced by the melt blown method have high tensile strength and high moisture permeability. Moreover, since it is also hydrophobic, it is suitable for the production of laminated sheets for packaging materials and sanitary materials.

The resin film layer is formed of a thermoplastic resin such as polyolefin. The polyolefin may be a homopolymer of an olefin, a copolymer of an olefin and a comonomer copolymerizable therewith, or a blend thereof, and is not particularly limited. . Examples of usable resins include polyethylene, polypropylene, ethylene / vinyl acetate copolymer, and ethylene / methacrylic acid copolymer. Among them, resins having good adhesiveness to the non-woven fabric are preferable.

The resin film layer on the side which is in direct contact with the non-woven fabric layer is preferably formed from a polyolefin resin having a density, a melt flow rate (MFR) and a melt tension (MT) within the following ranges. That is,
The density is preferably 0.870 to 0.935 (g / cm
³ ), more preferably 0.870-0.920 (g / c
m ³ ), more preferably 0.870 to 0.910 (g
/ Cm ³ ). According to ASTM D-1238,
MFR measured at 190 ° C. under a load of 2.16 kg is preferably 1 to 90 (g / 10 minutes), more preferably 3 to.
35 (g / 10 minutes), MT is preferably 0.
It is 1 to 10, more preferably 0.5 to 10 (g), and further preferably 0.5 to 8 (g). A polyolefin resin having a physical property within the range of these physical properties has an appropriate melt viscosity and therefore has good extrusion lamination moldability and imparts flexibility to the obtained laminated sheet.

Here, MT is an MT measuring machine manufactured by Toyo Seiki Seisaku-sho, using a nozzle diameter of 2.09 mmφ and a nozzle length of 8 m.
m, resin temperature 190 ° C., extrusion speed 15 (m / min), winding speed 10 to 20 (m / min).

As an example of a preferable polyolefin, ethylene and α having 3 to 20 carbon atoms and 0.1 to 10 mol% content are used.
-A resin which is a copolymer with an olefin and satisfies the above-mentioned physical property values can be mentioned. Examples of α-olefins include propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene. Further, this copolymer may be blended with high-pressure low-density polyethylene or a rubber-like polymer. When such a polyolefin is used, a laminated sheet having high elongation at break and high tensile strength can be easily obtained.

In the present invention, the resin film layer needs to be composed of at least two layers, and the resins forming each layer may be the same as or different from each other, but firmly adhere to each other. It is desirable to adopt a combination that The resin film layer in direct contact with the non-woven fabric is polyethylene, particularly ethylene and α-, from the viewpoint of adhesiveness with the non-woven fabric and imparting flexibility required for the laminated sheet.
It is preferable to form it from a copolymer with an olefin, but in that case, it is desirable to form the second or more resin film layers from the same polyethylene, because the adhesiveness to each other is good.

The resin forming the resin film layer may or may not contain an inorganic filler. In the case of obtaining a resin sheet having good air permeability and water resistance, it is desirable that all resin film layers contain an inorganic filler, and high air permeability is obtained in combination with the stretching effect described later. However, in order to obtain a resin sheet having good stretchability, the inorganic filler may not be contained, but at least one layer thereof preferably contains the inorganic filler. Especially when at least one layer after the second layer contains an inorganic filler,
The effect of increasing the elongation at break and the tensile strength of the laminated sheet can be obtained.

As the inorganic filler that can be used here, it is possible to use inorganic substances that are usually used as a plastic compounding agent, such as silica, calcium carbonate, magnesium hydroxide and the like. The content is preferably 20 in the resin.
To 70 (wt%), more preferably 50 to 65 (wt%). When the inorganic filler is contained within the above range, the laminated sheet becomes soft to the touch, and the "scratching sound" generated when the laminated sheet is touched is not generated, so that the touch feeling is improved.

In the laminated sheet of the present invention, when aiming for high air permeability, in addition to the layer constitution described so far, the entire laminate is further stretched in at least one direction, preferably in the transverse direction. Is desirable. The degree of stretching is preferably 1.1 to 5 times, more preferably 1.1 to
It is 3 times, and this stretching treatment not only increases the air permeability of the laminated sheet but also imparts flexibility. Note that the entire laminate may be stretched in two directions, the longitudinal direction and the lateral direction, and in this case, it is not always necessary to uniformly stretch in both directions, for example, strongly stretched in the lateral direction, It may be weakly stretched in the machine direction. Here, the traveling direction during the production of the laminated sheet is referred to as the vertical direction, and the direction perpendicular thereto is referred to as the horizontal direction.

In the resin film layer containing the inorganic filler,
This stretching treatment causes an interfacial peeling phenomenon between the resin phase and the inorganic filler phase, and as a result, many minute voids are generated. It is considered that the resin film layer exhibits moisture permeability when the voids communicate with each other.

As one mode of this laminated sheet, the water pressure resistance is preferably 1000 (mmH ₂ O) or more, and the water vapor permeability is preferably 1000 to 6000 (g / m ² · 24 h).
r), more preferably 2500 to 6000 (g / m ² ·
A sheet that is 24 hr) can be mentioned. Such a laminated sheet has a water-blocking property while maintaining air permeability.

Here, the water pressure resistance is JIS L1092.
According to the A method, the water vapor transmission rate (WVTR) is ASTM E-
It is the value measured according to 96. Usually, in a laminate comprising a nonwoven fabric and one resin film layer, the water pressure resistance is lowered due to the occurrence of pinholes. However, in the present invention, the constitution of the resin film layer is at least two layers as described above, It is possible to improve both the water-stopping property and the air permeability of the laminated sheet, which are contradictory properties.

Such a laminated sheet is water-permeable and breathable, and as is clear from the above-mentioned thickness constitution, it is a relatively thin sheet and has a cross-like feel and flexibility. It is suitable for use as packaging material and sanitary material because it has both. In particular, it is suitable for a member usually called a back sheet part of a disposable diaper by utilizing its high water pressure resistance and moisture permeability.

As another embodiment of this laminated sheet, the elongation at break in the transverse direction measured by a tensile test is preferably 2 or more.
00-1000%, more preferably 300-900%,
Further, the tensile strength in the lateral direction is preferably 5 to 30 (N / c
m), and more preferably 8 to 25 (N / cm).

In the tensile test, Model 201 manufactured by INTESCO was used, a test piece having a width of 25 mm was fixed at a chuck distance of 100 mm, and a tensile speed of 100 (mm /
Min). In addition, the traveling direction in the manufacturing process of the laminated sheet is referred to as the vertical direction, and the direction perpendicular thereto is referred to as the horizontal direction.

When the elongation at break and the tensile strength are within the above-mentioned ranges, the laminated sheet has a cross-like feel represented by the texture, bulkiness, touch, softness, stretchability, etc. retained by the nonwoven fabric itself. Also appears in a state close to that, and the stretchability of the resin film itself appears in the laminated sheet. In the present invention, the resin film layer is formed of at least two layers, but when the resin film layer having the same thickness as that of one layer is formed, the elongation at break of the laminated sheet becomes smaller than the above range. , I can't get a cross feeling.

As is apparent from the above-mentioned thickness structure, such a laminated sheet is also a relatively thin sheet and has a cross-like feel and flexibility, so that it is used as a packaging material or a sanitary material. Suitable for use in. Utilizing its high elongation at break and tensile strength, it is particularly suitable for an adhesive band member of a disposable diaper.

Method for Producing Laminated Sheet The first method for producing a laminated sheet according to the present invention is to extrude a molten resin onto a non-woven fabric layer and then pass the resin through a gap between a pair of cooling rolls and nip rolls to form a laminate. It comprises a first step of forming and a second step of coating a new resin layer on the resin layer.

The laminator used for producing the laminate is basically composed of at least an extruder equipped with a T die and a pair of rolls composed of a cooling roll and a nip roll. First, it is desirable that the non-woven fabric supplied to the laminator is adjusted to a state in which substantially no longitudinal tension is applied, preferably 0.1 to 5 (kg / m). When the non-woven fabric is supplied in such a state that almost no tension is applied thereto, wrinkles do not occur in the non-woven fabric layer in the laminate sheet, and the obtained laminate sheet shows a good appearance.

The temperature of the molten resin extruded from the T die is
It is desirable to measure the temperature immediately after leaving the die, that is, the temperature under the die, and maintain it at 200 to 280 ° C, preferably 200 to 250 ° C. This temperature is adjusted to a temperature slightly lower than the resin temperature when the polyolefin is normally extruded and laminated. When the temperature of the molten resin under the die is within the above range, the resulting laminated sheet retains the original feel of the nonwoven fabric.

The non-woven fabric and the molten resin layer extruded on the surface of the non-woven fabric are then sent to a gap between a pair of rolls consisting of a cooling roll and a nip roll, and the nip pressure applied there integrates both layers and cools them. A laminated body is formed. The nip pressure at this time is based on the degree that the molten resin permeates the nonwoven fabric layer shallowly, and specifically, it is 5 to 20.
(Kg / cm ² ), preferably 7 to 18 (kg / c
m ² ). Even within this low nip pressure range, the non-woven fabric layer and the resin film layer are joined and integrated, and pinholes do not occur in the resin film layer. It keeps the feel.

After that, the second step of coating the second resin film layer on the surface of the first resin film layer formed on the surface of the nonwoven fabric in the previous step is performed. The resin film layer to be newly coated may be a film made of the same material as the first resin film layer, or may be a film made of a different material, and the thermoplastic resin such as the above-mentioned polyolefin may be used. it can. The second step may be performed by the extrusion lamination method as in the previous step, or may be performed by a method of directly coating a preformed film, for example, a hot melt lamination method or a sand lamination method. When the extrusion lamination method using the same resin as the first resin film layer is adopted, it is possible to produce a laminated sheet having high productivity and good physical properties.

In the second method for producing a laminated sheet according to the present invention, the same kind or different kinds of molten resins are supplied in a film form between the non-woven fabric and the resin film to directly form a laminated body of three layers. Is the way to do it. In this method, the molten resin is extruded from a T-die into a film at a temperature below the die of 200 to 280 ° C., preferably 200 to 250 ° C., and then the three layers are placed in a gap between a pair of rolls composed of a nip roll and a cooling roll. Nip pressure 5-20 (kg / c
m ² ), preferably 7 to 18 (kg / cm ² ) can be used. Also in this method, it is desirable that the nonwoven fabric is supplied after being adjusted to a tension in which substantially no longitudinal tension is applied, preferably 0.1 to 5 (kg / m).

The laminate thus obtained is then sent, if necessary, to the step of stretching in at least one direction, and this stretching step produces a laminated sheet having high moisture permeability. This is an effective means for the purpose.

The stretching device may be a general device for stretching the laminate in the machine direction and / or the transverse direction, or may be a device called a gear stretching device. The draw ratio is preferably 1.1 to 5 times,
It is more preferably 1.1 to 3 times. Note that this stretching step may be performed continuously with each step of the method for producing a laminate, or may be performed independently after once producing a laminate.

The gear stretching device is composed of a pair of rolls on the surface of which a number of discs are arranged and fixed at equal intervals.
Each of the rolls rotates in the opposite direction, and the discs are inserted and rotated so as not to contact each other. When the laminated body is supplied between the pair of rolls, the laminated body is inserted between the discs rotating in opposite directions, and the laminated body is stretched in the transverse direction and / or the longitudinal direction to form a flexible laminated sheet. Change. When this gear stretching device is used, stretching of the laminated body is mainly performed in the lateral direction. However, in conditions such as the shape and depth of the gear related to the device, the supply speed of the laminated body, the rotation speed of the roll, etc. The stretching ratio in each direction applied to the laminate can be adjusted by changing the conditions involved.

In the present invention, the first resin film layer is formed on the non-woven fabric under the above-mentioned extrusion lamination conditions, and the second and subsequent resin film layers are coated on the first resin film layer. Since the thickness is divided into two or more times, it is considered that this method gives the laminated sheet a waterproofness and a cross-like feel. When the cross section of the laminated sheet is observed with a microscope, it is found that the resin forming the first resin film layer has only penetrated into the non-woven fabric layer to a shallow extent, which gives the laminated sheet a cross-like feel. It seems to be the cause. Furthermore, the resin film layers after the second layer also contribute to the prevention of pinholes, and it is considered that these effects synergize to enhance the water resistance of the laminated sheet.

However, one resin film layer having the same thickness is used.
It has been confirmed by microscopic observation that the molten resin penetrates deeply into the nonwoven fabric layer when it is formed on the nonwoven fabric surface by the single extrusion lamination method. The water resistance of the obtained laminated sheet is lowered, and a hard touch feeling is exhibited, and a cross-like touch cannot be obtained.

[0060]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 A nonwoven fabric was formed from polypropylene continuous fibers having a thickness of 2 denier, and the fibers were fixed by spot bonding.
(G / m ² ) and a width of 500 mm, a spunbonded nonwoven fabric was prepared.

As a resin for forming a resin film layer, an ethylene-4-methyl-1-pentene copolymer (density 0.915 g / cm ³ , MFR 20 g / 10 minutes, MT
1.8 g) A resin composition consisting of 40% by weight and 60% by weight of calcium carbonate was prepared.

The above resin composition was supplied to an extruder having a width of 800 mm and a screw diameter of 65 mm, and extruded so that the temperature under the die was 250 ° C., and continuously supplied onto the surface of the nonwoven fabric. Coated. At this time, the tension applied to the nonwoven fabric was 3 (kg / m).

Then, the two-layer body was cooled to a cooling roll (temperature 2).
(0 ° C.) and a nip roll having a width of 900 mm to supply a pair of roll gaps, and a laminate was manufactured at a processing speed of 50 (m / min). At this time, the nip pressure is 15 (kg /
cm ² ). The basis weight of the resin film layer is 15
(G / m ² ).

Then, the laminated body was supplied to the same laminator as above, and the same resin composition was extruded on the resin film layer so as to have a basis weight of 15 (g / m ² ) and laminated to form a second resin film. The layers were molded.

Then, the laminate was passed through a gear stretching device and stretched 1.6 times in the transverse direction and 1.1 times in the longitudinal direction. The gear stretching device used was a disc thickness of 0.7.
The size was 62 mm, the disk clearance was 0.537 mm, the gear roll diameter was 152 mm, the gear roll width was 350 mm, and the processing depth (engagement depth) was 3 mm.

The physical properties of the obtained laminated sheet are shown in Table 1. In Table 1, the number of pinholes was measured by the following method. That is, colored water was permeated from the film layer side under a pressure of 50 mmH ₂ O, and the number of coloring points on the nonwoven fabric side was counted.

(Comparative Example 1) In Example 1, except that the first resin film layer was extrusion-laminated to have a basis weight of 30 (g / m ² ), and the second resin film layer was not formed. Was performed in the same manner as in Example 1. The physical properties of the obtained laminated sheet are also shown in Table 1.

(Comparative Examples 2 to 3) A laminated sheet was formed in the same manner as in Example 1 except that the temperature under the die and the nip pressure were changed to those shown in Table 1. The physical properties of the obtained laminated sheet are also shown in Table 1.

[0070]

[Table 1] * Portion with pinhole ** Portion without pinhole

(Example 2) A nonwoven fabric was formed from polypropylene continuous fibers having a thickness of 2 denier, and the fibers were fixed by spot bonding.
(G / m ² ) and a width of 500 mm, a spunbonded nonwoven fabric was prepared. The elongation at break of this nonwoven fabric in the transverse direction is 40.
%, And the tensile strength in the lateral direction was 3 (N / cm).

As a resin for forming the resin film layer, an ethylene / 1-hexene copolymer (having a density of 0.900) is used.
g / cm ³ , MFR 9 g / 10 min, MT 2 g) were prepared. The 55 μm-thick film molded from this resin had a lateral elongation at break of 700%.

The above resin was supplied to an extruder having a T-die having a width of 800 mm and a screw diameter of 65 mm, extruded so that the temperature under the die was 250 ° C., and the surface of the nonwoven fabric continuously supplied was coated. . At this time, the tension applied to the nonwoven fabric was 3 (kg / m).

Then, the two-layer body was cooled to a cooling roll (temperature 2
(0 ° C.) and a nip roll having a width of 900 mm to supply a pair of roll gaps, and a laminate was manufactured at a processing speed of 50 (m / min). At this time, the nip pressure is 15 (kg /
cm ² ). The basis weight of the resin film layer is 25
(G / m ² ).

Then, the laminated body was supplied to the same laminator as described above, and the same resin was extruded on the resin film layer so as to have a basis weight of 30 (g / m ² ) and laminated to form a second resin film layer. Molded. Table 2 shows the physical properties of the obtained laminated sheet.

(Comparative Example 4) In Example 2, except that the first resin film layer was extrusion-laminated to have a basis weight of 55 (g / m ² ), and the second resin film layer was not formed. Was performed in the same manner as in Example 2. The physical properties of the obtained laminated sheet are also shown in Table 2.

(Comparative Example 5) A laminated sheet was formed in the same manner as in Example 2 except that the temperature under the die was changed to 285 ° C. The physical properties of the obtained laminated sheet are also shown in Table 2.

[0078]

[Table 2]

[0079]

EFFECTS OF THE INVENTION The laminated sheet according to the present invention comprises a non-woven fabric layer and a resin film layer, but retains the cloth-like touch inherent to the non-woven fabric. In addition, a sheet having a high degree of waterproofing property and breathability has been obtained, and is suitable for a waterproofing material application requiring a cross-like feel, particularly for packaging materials and sanitary materials. Further, a sheet that retains a high degree of elasticity inherent in a resin sheet has been obtained, and can be used as a packaging material or a sanitary material that requires high tensile strength and elongation. Further, according to the method for producing a laminated sheet of the present invention, a laminated sheet having such characteristics can be produced with high productivity.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhiko Masuda             580-32 Nagaura, Sodegaura-shi, Chiba Mitsui Chemicals, Inc.             Inside the company F term (reference) 4F100 AA00B AA00C AA00H AK01B                       AK01C AK03A AK03B AK03C                       AK03D AK63B AK63C BA03                       BA04 BA07 BA10A BA10C                       BA13 CA23B CA23C DG12A                       DG12D EC031 EC032 EH231                       EH232 EJ191 EJ37 EJ373                       GB15 GB66 GB72 JA06B                       JA13A JA13B JA13D JA20B                       JD02 JD04 JK02 JK08 JK20                       YY00 YY00A YY00B YY00D                 4F210 AA03 AA03E AB11 AD16                       AE10 AG01 AG03 QA04 QG01                       QG15 QG18                 4L047 AA14 AB02 AB03 BA09 CA06                       CA19 CB01 CB08 CB10

Claims (21)

[Claims] 1. A laminate in which a resin film comprising at least two layers is bonded onto a non-woven fabric, wherein a part of the resin film layer on the side in contact with the non-woven fabric penetrates into the fiber gap of the non-woven fabric. And laminated sheet. 2. The laminate is stretched in at least one direction and has a water pressure resistance of 1000 (mmH ₂ O).
Above, and the water vapor transmission rate is 1000 to 6000 (g / m
Laminated sheet according to claim 1, characterized in that a ² · 24hr). 3. The laminate has a transverse elongation at break of 200 to 1000% and a transverse tensile strength of 5 to 3.
It is 0 (N / cm), The laminated sheet of Claim 1 characterized by the above-mentioned. 4. The unit weight of the non-woven fabric layer is 10-6.
It is 0 (g / m < ² >), The laminated sheet in any one of Claims 1-3 characterized by the above-mentioned. 5. The laminated sheet according to claim 1, wherein the nonwoven fabric layer is a spunbonded nonwoven fabric or a laminated nonwoven fabric of a spunbonded nonwoven fabric and a meltblown nonwoven fabric. 6. The laminated sheet according to claim 1, wherein the nonwoven fabric layer is formed of polyolefin. 7. The laminated sheet according to claim 1, wherein the resin film layer has a total basis weight of 10 to 60 (g / m ² ). 8. The laminated sheet according to any one of claims 1 to 7, wherein the resin film layer on the side in contact with the non-woven fabric layer has a basis weight of 5 to 50 (g / m ² ). . 9. The laminated sheet according to claim 1, wherein at least one layer of the resin film layer is formed of a resin containing an inorganic filler. 10. The laminated sheet according to claim 9, wherein the resin film layer contains 20 to 70% by weight of an inorganic filler. 11. The resin film layer is formed of a polyolefin.
The laminated sheet according to any one of 1. 12. The polyolefin is ethylene / α
-Olefin copolymers are included.
1. The laminated sheet according to 1. 13. The resin film layer on the side in contact with the non-woven fabric layer has a density of 0.870 to 0.935 (g / cm ³ ),
The laminated sheet according to any one of claims 1 to 12, which is formed from a polyolefin having a melt flow rate of 1 to 90 (g / 10 minutes) and a melt tension of 0.5 to 10 (g). 14. The laminated sheet according to claim 1, wherein the laminated body is stretched in at least one direction by 1.1 to 5 times. 15. A molten resin is extruded on a surface of a nonwoven fabric from a T-die at a die temperature of 200 to 280 ° C. into a film, and then a nip pressure of 5 to 20 (kg) is applied to a gap between a pair of nip rolls and a cooling roll. / Cm ² ) to form a two-layer laminate in which the non-woven fabric layer and the resin film layer are integrated, and the same or different resin film layer is coated on the resin film layer. And a second step of forming a laminated body. 16. A molten resin of the same type or different types between the non-woven fabric and the resin film is passed from the T die to a die temperature of 200 to 28.
The film is extruded at 0 ° C. into a film, and then a nip pressure of 5 to 2 is applied to a gap between a pair of nip rolls and a cooling roll.
A method for producing a laminated sheet, which comprises passing the mixture under the condition of 0 (kg / cm ² ) to form a laminated body in which the three layers are integrated. 17. The laminated sheet according to claim 15, wherein the supplied non-woven fabric is applied with a tension of 0.1 to 5 (kg / m) in the longitudinal direction. Production method. 18. The method for producing a laminated sheet according to claim 15, wherein at least one layer of the resin film layer contains an inorganic filler. 19. The laminated sheet according to claim 15, wherein at least one of the resin film layers contains an inorganic filler in an amount of 20 to 70% by weight. Method. 20. The method for producing a laminated sheet according to any one of claims 15 to 19, further comprising the step of stretching the obtained laminate in at least one direction. 21. The method for producing a laminated sheet according to claim 20, wherein the stretching step is performed by supplying the laminate to a gear stretching device.