JP2000202960A - Laminate cloth and its manufacturing method - Google Patents

Abstract

(57) [Summary] A base fabric and a laminate layer have high peel strength,
It provides a laminate cloth that has excellent flexibility and abrasion resistance, has moderate slip properties, and has no pinholes. SOLUTION: JIS K6 is provided on both sides of a base fabric 2 woven and knitted using a polypropylene multifilament as a weft.
Intermediate layer 3 composed mainly of a soft propylene polymer having a flexural modulus of 800 MPa or less as measured by 758
And a surface layer 4 made of a propylene-ethylene random copolymer. Further, after laminating and cooling the intermediate layer 3, when laminating the surface layer 4 consisting essentially of a propylene-ethylene random copolymer on the surface thereof, the intermediate layer 3 is cooled at a cooling roll surface temperature of 50 ° C. or more. This is a method for producing a laminated cloth to be laminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a laminate cloth suitably used for sheets and covers.

[0002]

2. Description of the Related Art Hitherto, as a cross sheet used for sheets, covers, and the like, many laminated sheets having a resin layer provided on one or both sides of a fiber cloth are known. Sheets for these applications include high strength that can withstand the tensile force at the time of sheet stretching and flapping at the time of use, the flexibility to handle easily as covers, and the fitting to the target object, and the edge processing and sheet There is a demand for good adhesion due to thermal welding during secondary processing such as joining. As a sheet for such an application, a cross sheet obtained by laminating a film made of polyvinyl chloride or the like on a cloth made of nylon or polyester fibers is often used. These cloth sheets are made of multi-filaments such as nylon and polyester fibers to maintain high strength and flexibility, and form a laminated sheet by laminating highly flexible polyvinyl chloride. Polyvinyl chloride has not been satisfactory because of problems such as bleeding of plasticizer, generation of toxic gas during incineration, and heavy workability due to large specific gravity.

In order to solve such a problem, in recent years,
A flame-resistant laminate cloth in which a polypropylene layer is laminated on a woven or knitted fabric made of a polypropylene multifilament, which has excellent filament formability and does not generate toxic gas, has been tried. However, a laminate obtained by laminating a polypropylene layer on a base cloth made of polypropylene multifilaments as the weft of a woven or knitted fabric is inferior in flexibility due to the high flexural modulus of polypropylene and is not easily handled as sheets and covers. When a polypropylene polymer having a low flexural modulus is used, there is a problem that the abrasion resistance and lubricity of the sheet surface are reduced, which is not preferable.

Another problem is that high peel strength cannot be obtained due to poor adhesion between the polypropylene multifilament base fabric and the polypropylene polymer layer. Therefore, in order to improve the adhesion between the base fabric and the polypropylene-based polymer layer and obtain a high peel strength, let the polypropylene-based polymer layer be gradually cooled during laminating so that the polypropylene-based polymer layer bites into the base fabric. In this case, there is also a problem that cooling of the polypropylene-based polymer layer in the opening portion of the base fabric is delayed and pinholes are generated.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a base fabric and a laminate layer having high peel strength, excellent flexibility and abrasion resistance, and having an appropriate slip property. It is an object of the present invention to provide a laminated cloth having no pinholes and a method for manufacturing the same.

[0006]

Means for Solving the Problems In order to solve the above problems technically, the present invention provides a JIS K67 on both sides of a woven or knitted fabric using a polypropylene multifilament as a weft.
The first gist is a laminate cloth formed by laminating an intermediate layer mainly composed of a soft propylene-based polymer having a flexural modulus of 800 MPa or less as measured according to 58 and a surface layer made of a propylene-ethylene random copolymer. .

A method for obtaining a laminate cloth according to the present invention, wherein a bending elastic modulus measured by JIS K6758 by extrusion lamination on both sides of a woven or knitted fabric using a polypropylene multifilament as a weft, is 800M.
The second aspect is a method for producing a laminate cloth in which an intermediate layer mainly composed of a soft propylene polymer having a pressure of not more than Pa is laminated and cooled, and then a surface layer of a propylene-ethylene random copolymer is laminated on the surface thereof. And

Further, the present invention provides a method for obtaining a laminate cloth according to the present invention, wherein a soft propylene-based weight having a flexural modulus of 800 MPa or less as measured by JIS K6758 is provided on both surfaces of a woven or knitted fabric using a polypropylene multifilament as a weft. This is an extrusion lamination method in which an intermediate layer mainly composed of coalescing is laminated and cooled, and then a surface layer made of a propylene-ethylene random copolymer is laminated on the surface thereof. A third aspect of the present invention is a method of manufacturing a laminate cloth, which is set at a temperature of not less than ° C.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The polypropylene used for the polypropylene multifilament of the present invention is preferably a polypropylene having high crystallinity and a high stretching effect. Specifically, propylene homopolymer, propylene-ethylene block Copolymer, propylene-ethylene random copolymer, and the like. Of these,
A polypropylene homopolymer having excellent moldability and high strength is preferable, and particularly, the isotactic pentad fraction is 0.1.
Highly crystalline polypropylene of 95 or more is preferred.
These polypropylenes may be used alone or in combination of two or more.

The method for producing the polypropylene multifilament is not particularly limited, and a known method for producing a multifilament is appropriately employed.
The fineness of the multifilament is preferably from 100 to 3000 denier (hereinafter, referred to as d), and more preferably from 300 to 1500 d.

Next, a woven or knitted fabric is formed by weaving and knitting using the polypropylene multifilaments as warp yarns. The weaving and knitting structure is not particularly limited, and examples of the woven fabric include various woven fabrics such as plain weave, woven weave, leno weave, and the like. Include tricot, Miranese, and Russell versions.

The intermediate layer laminated on both sides of the woven or knitted fabric is J
Flexural modulus measured by ISK6758 is 800MP
The main component is a soft propylene-based polymer having a of not more than a, preferably not more than 500 MPa, and its content is preferably at least 60% by weight. Examples of the soft propylene polymer include a) a crystalline propylene polymer having an isotactic index of greater than 80;
Parts by weight, b) 5 to 20 parts by weight of an ethylene-containing copolymer component which is insoluble in xylene at room temperature and c) a copolymer component of ethylene and an α-olefin and optionally a small proportion of a diene (the component is 40% by weight of ethylene). %, And soluble in xylene at room temperature).
50% to 90% by weight of the sum of the components (b) and (c)
% And the weight ratio of (b) / (c) is less than 0.4.

As the crystalline propylene-based polymer as the component (a), a propylene homopolymer or propylene and an α-olefin other than ethylene or propylene (particularly having 4 to 4 carbon atoms)
10 is preferable) and a propylene content of 85% by weight or more in monomer conversion. As the α-olefin constituting the copolymer of the component c), those having 4 to 10 carbon atoms as described above are preferable.

These propylene-based polymer compositions can be prepared by the multi-stage polymerization of ethylene, propylene and, if necessary, diene by the methods described in JP-A-6-25367 and JP-A-6-25439. It can be obtained by copolymerization.

The soft propylene-based polymer is obtained by random copolymerization of propylene and an α-olefin having 2 to 8 carbon atoms, especially
A copolymer of 35 mol% and 65 to 80 mol% of ethylene, or 0.1 to 20 mol% of diene
An ethylene-propylene copolymer rubber which is an ethylene-propylene-diene copolymer containing is preferably used. Ethylene-propylene copolymer rubber has a density of 0.8
It is a low crystalline or non-crystalline polymer at 5 to 0.90 g / cm ³ .

The soft propylene polymer has an MFR of 1
３０30 g / 10 min., Preferably 5-20 g / 10 min.
It is better to select from the range of min. MFR is 1g /
If it is less than 10 min., The fluidity becomes poor, and 30 g / 10
If it exceeds min., the tensile strength and the like will decrease, which is not desirable.

The soft propylene polymer is JISK
The flexural modulus measured according to 6758 is preferably 800 MPa or less, particularly preferably 500 MPa or less. When the flexural modulus is 800 MPa or more, the flexibility of the obtained laminate cloth is insufficient, and a sufficient improvement effect cannot be obtained.

The soft propylene-based polymer includes high-density polyethylene, linear low-density polyethylene, low-density polyethylene, ultra-low-density polyethylene, ethylene-vinyl acetate copolymer and ethylene-alkyl acrylate copolymer. One or more polypropylene resins such as polypropylene, propylene-ethylene block copolymer, propylene-ethylene random copolymer, and syndiotactic polypropylene may be used alone or in combination of two or more. The amount is preferably 40
%, More preferably less than 30% by weight. If the amount exceeds 40% by weight, the flexibility is undesirably reduced.

The propylene-ethylene random copolymer used for the surface layer of the laminate cloth of the present invention is a random copolymer of propylene and ethylene produced by a known method, and has an ethylene content of 1 to 10% by weight. , Preferably 4 to 7% by weight. It is also possible to mix other polyolefin-based resins other than the propylene-ethylene copolymer without departing from the spirit of the present invention. MF of the propylene-ethylene copolymer
R is preferably selected in the range of 1 to 30 g / 10 min., More preferably 5 to 20 g / 10 min.

By providing a surface layer composed of the propylene-ethylene random copolymer, heat sealability
A laminate cloth having excellent wear resistance and slip properties can be obtained.

In the present invention, a laminate cloth is formed by laminating the intermediate layer and the surface layer on both surfaces of a woven or knitted fabric using the polypropylene multifilament as the weft.

As a method of laminating the intermediate layer and the surface layer on both surfaces of the woven or knitted fabric, a known extrusion laminating method is used.
A multilayer extrusion lamination method in which the intermediate layer and the surface layer are simultaneously laminated may be used, but it is preferable to use a two-stage lamination method in which the intermediate layer is laminated and cooled, and then the surface layer is laminated.

In the above extrusion laminating method, the extrusion temperature of the soft propylene polymer used for the intermediate layer or the resin composition comprising the soft propylene polymer and another polyolefin resin is preferably less than 250 ° C., and preferably less than 230 ° C. More preferred. If the extrusion temperature exceeds 250 ° C., the roll release from the cooling roll deteriorates, which is not preferable.

In the extrusion laminating method, the surface temperature of the cooling roll for laminating the intermediate layer is preferably set to 50 ° C. or higher. When the surface temperature is lower than 50 ° C., the cooling rate increases, and there is no time for the molten resin to enter the gap between the base fabrics and generate an anchoring effect, and a sufficient peel strength between the base fabric and the laminate layer is obtained. Not so desirable. As a method of setting the surface of the cooling roll to 50 ° C. or higher, the temperature may be adjusted by the temperature of water passing through the cooling roll, or may be adjusted by providing a coating layer of silicon rubber or the like on the cooling roll.

The thickness of the intermediate layer provided by the extrusion lamination method is preferably 60 to 100 μm on one side. If the thickness of the intermediate layer is less than 60 μm, sufficient peel strength between the base fabric and the laminate layer cannot be obtained, and if it exceeds 100 μm, flexibility is lost, which is not preferable. The thickness of the surface layer provided by the extrusion lamination method is preferably 10 to 30 μm on one side. If the thickness of the surface layer is less than 10 μm, the wear resistance and lubricity cannot be obtained on the surface layer, and the effect of closing the pinholes generated in the intermediate layer cannot be sufficiently achieved.
Even if it exceeds μm, wear resistance and lubricity are not further improved, and it is not economical.

The weight of the flameproof laminate cloth of the present invention is preferably 100 to 500 g / m ² , and 150 to 3 g / m ^2.
50 g / m ² is more preferred.

The polyolefin resin used in the present invention includes an antioxidant, an ultraviolet absorber, a light stabilizer, a dispersant, a lubricant, an antistatic agent, a pigment, and an inorganic filler without departing from the spirit of the present invention. Ordinarily used additives such as a crosslinking agent, a foaming agent and a nucleating agent may be blended.

[0028]

EXAMPLES Example 1: Polypropylene (MFR = 20 g)
/ 10 min., Density = 0.90 g / cm ³ , Tm = 15
Bis (2,2,6,6-) as a light stabilizer
A multifilament having a total fineness of 680 d / 120 f was formed using a composition containing 1% by weight of tetramethyl-4-piperidyl) sebacate. The polypropylene multifilament thus obtained was used as warp yarn to obtain a plain weave base fabric 2 having a driving density of 20 × 24 filaments / inch. The basis weight of the base fabric 2 was about 140 g / m ² .

A soft propylene polymer for the intermediate layer was prepared as follows. That is, it was produced by a two-stage polymerization method of propylene and ethylene. The first stage product of the resulting polymer composition has an ethylene content of 3.0% by weight and a xylene solubles (S _A ) of 9.4% by weight, and the second stage product has a binary copolymer ( b + c) (70% by weight of the total), 63.4% by weight of xylene-soluble component (S _F ), component b)
9.45% by weight, component c) 60.55% by weight. The above soft propylene polymer has an MFR of 25 g / 10 mi.
n., density = 0.89 g / cm ³ , and the flexural modulus measured by JIS K6758 was 130 MPa.

Also, 98% by weight of a propylene-ethylene random copolymer (MFR = 18.0 g / 10 min., Ethylene content = 6.0% by weight, flexural modulus measured by JIS K6758: 850 MPa), 2% by weight of white pigment % To prepare a resin composition for the surface layer.

Next, an intermediate layer 3 having a thickness of 80 μm is laminated on both surfaces of the base fabric 2 previously formed by extrusion lamination using the above-mentioned soft propylene polymer for the intermediate layer, cooled, and cooled. The resin composition was laminated on the surface layer 4 to a thickness of 15 μm by extrusion lamination, and the basis weight was 310 g / m 2.
^{Thus, two} laminate cloths 1 were formed. The surface temperature of the cooling roll for laminating the intermediate layer 3 was 60 ° C.

The obtained laminate cloth 1 is made according to JISL
The hardness value measured by 1096 (cantilever method) is 80.
mm, it was foldable and easy to handle. The peel strength between the base fabric 2 and the mid layer 3 was 3000 g / 15 mm. Further, the maximum tensile load is 128 kgf / 3 cm in the vertical direction and 122 kF in the horizontal direction.
gf / 3 cm, the maximum elongation was 18.0% in the vertical direction and 20.0% in the horizontal direction.

Example 2 Example 2 was repeated except that a soft propylene polymer for the intermediate layer was prepared as follows. That is, a propylene-ethylene random copolymer (MFR = 18.0 g / 10 min., Ethylene content =
6.0% by weight, Tm = 128.4 ° C) and 20 parts by weight of ethylene-propylene copolymer rubber (Mooney viscosity (ML
_{(1 + 4} , 100 ° C.) = 90, propylene content = 27% by weight) and 80 parts by weight (the flexural modulus measured by JIS K6758 is 340 MPa).

The obtained laminate cloth had a measured bending resistance of 88 mm, had foldable flexibility, and had good handleability. The peel strength between the base cloth 2 and the intermediate layer 3 was 2600 g / 15 mm. Further, the tensile maximum point load is 124 kgf / 3 cm in the vertical direction, 116 kgf / 3 cm in the horizontal direction, and the maximum elongation is 18.6 in the vertical direction.
% And 20.4% in the horizontal direction.

Comparative Example 1 As a resin for the intermediate layer, a propylene-ethylene random copolymer (MFR = 18.0 g) was used.
/ 10 min., Ethylene content = 6.0% by weight, JIS
The flexural modulus measured by K6758 is 850 MPa)
A laminate cloth was obtained in the same manner as in Example 1 except for using. The obtained laminated cloth sheet had a measured bending resistance of 140 mm and lacked flexibility.

Comparative Example 2 A laminate cloth 1 was obtained in the same manner as in Example 1 except that the surface temperature of the cooling roll for laminating the intermediate layer 3 was 20 ° C. The peel strength between the base cloth 2 and the intermediate layer 3 of the obtained laminate cloth 1 is 550 g / 1.
At 5 mm, peeling easily occurred, which was not preferable.

Comparative Example 3 A laminate cloth 1 was obtained in the same manner as in Example 1 except that the intermediate layer 3 and the surface layer 4 were subjected to a multilayer extrusion lamination method. The obtained laminate cloth 1 is
Many pinholes were generated, which was not preferable.

[0038]

As described above, the present invention provides an intermediate layer mainly composed of a specific soft propylene-based polymer, A laminate cloth obtained by laminating a surface layer made of an ethylene random copolymer,
It is lightweight, high-strength, excellent in flexibility and abrasion resistance, and has a moderate slip property. Also,
When laminating a laminate layer by extrusion lamination method,
Laminate cloth with no pinholes by performing lamination twice while allowing the intermediate layer to enter the gaps between the base fabrics while gradually cooling to create an anchoring effect and improve the peel strength between the base fabric and the laminate layer. Could be obtained. The laminate cloth of the present invention has better cold resistance and antifouling property than the conventionally used vinyl chloride resin coated type.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a laminate cloth according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laminate cloth 2 Base cloth 3 Middle layer 4 Surface layer

 ──────────────────────────────────────────────────の Continued on the front page F term (reference) 4F100 AK07A AK07B AK07C AK64D AK64E AL03D AL03E BA05 BA06 BA10D BA10E BA13 CA13 DG04A DG07A DG12A DG13A EH232 EJ502 GB90 JJ04 JK06 JK07BJKJKJJJJJJKJKJK13

Claims (3)

[Claims] 1. An intermediate layer mainly composed of a soft propylene-based polymer having a flexural modulus of 800 MPa or less as measured by JIS K6758, on both sides of a woven or knitted fabric using a polypropylene multifilament as a weft yarn. A laminate cloth formed by laminating a surface layer made of an ethylene random copolymer. 2. A flexural modulus of 800 measured on both sides of a woven or knitted fabric using a polypropylene multifilament as a weft by extrusion lamination according to JIS K6758.
A method for producing a laminate cloth comprising laminating an intermediate layer mainly composed of a soft propylene-based polymer having a pressure of not more than MPa, cooling, and then laminating a surface layer made of a propylene-ethylene random copolymer on the surface thereof. 3. An intermediate layer mainly composed of a soft propylene polymer having a flexural modulus of 800 MPa or less as measured by JIS K6758 is laminated on both sides of a woven or knitted fabric using a polypropylene multifilament as a weft. A laminating method comprising laminating a surface layer comprising a propylene-ethylene random copolymer on the surface thereof, wherein the surface temperature of a cooling roll for laminating the intermediate layer is set to 50 ° C. or higher. Cloth manufacturing method.