JPH1044277A - Moisture permeable water resistant fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form fabric with dimensional stability and moisture permeable water resistivity at low cost by laminating and gluing fabric partially to a micro-porous film made of a high polymeric molecular weight polyethylene with a specific molecular weight and having a number of fine pores with a specific porous diameter. SOLUTION: Fabric is laminated and glued through partial adhesion to a micro-porous film made of high molecular weight polyethylene with a molecular weight of 5×105-7×106 and having a number of fine pores with a porous diameter of 0.1-2.0μm. Such a mocro-porous film is formed that e.g. a solution of polyethylene dissolved in a solvent of decalin or the like is extruded from a slit-die for forming a gel film to be stretched after an evaporation of the solvent. The weight thereof is preferable to be of the order of 7-15g/m<2> , the porosity is 60-90%, and the permeability is 0.2-3.0cc/cm<2> /sec. The fabric is suitably made of polyester, and the weight is preferable to be of the order of 25-150g/m<2> , and the permeability is to be 0.5-3.0cc/cm<2> .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture-permeable waterproof fabric obtained by laminating a microporous film and a fabric.

[0002]

2. Description of the Related Art A breathable waterproof fabric obtained by laminating a microporous film made of polytetrafluoroethylene and a fabric is used under various trade names, such as clothing, under the trade name GORE-TEX.

[0003] However, polytetrafluoroethylene has the problem that the microporous film obtained is very expensive because of its difficulty in molding and processing. Furthermore, when a film having a high porosity is to be produced, There is a disadvantage that the strength of the film is reduced.

On the other hand, a high-strength, high-modulus film made of high-molecular-weight polyethylene is also known (Japanese Patent Application Laid-Open No. 61-84225), because the cost is lower than that of a polytetrafluoroethylene film. In recent years, its applications have been expanding.

[0005] A microporous film made of polyethylene having a high molecular weight has also been proposed (Japanese Unexamined Patent Publication No. Hei.
JP-A-232242) and its use as a breathable sandwich layer of clothing is also known (Japanese Unexamined Patent Publication (Kokai) No. Heisei 5 (1993)).
-98064).

However, simply using such a high-molecular-weight polyethylene microporous film as a breathable sandwich layer of clothing is inferior in dimensional stability and does not provide sufficient moisture permeability and waterproofness.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and to provide an inexpensive fabric having excellent dimensional stability and moisture permeability and waterproofness.

[0008]

Means for Solving the Problems As a result of repeated studies to solve the above problems, the present inventors have found that a fabric can be laminated and bonded to a microporous film made of high molecular weight polyethylene by partial adhesion. And completed the present invention.

That is, according to the present invention, (1) the molecular weight is 5
X 105 to 7 x 106 ultra high molecular weight polyethylene, pore size 0.1 to 2.0 micron microporous film having a large number of micropores, laminated fabric by partial adhesion,
(2) a moisture-permeable and waterproof fabric characterized in that it is laminated.
The moisture-permeable waterproof fabric according to the above (1), wherein the fabric is a polyester woven fabric, and (3) the transparent fabric according to the above (1) or (2), wherein the partial adhesion is in the form of dots, lines or meshes. The moisture-permeable waterproof cloth according to the above (1), (2) or (3), wherein the wet-waterproof cloth and (4) the microporous film and the cloth are dry-laminated by partial adhesion using a hot melt adhesive. Provided.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, polyethylene used for a microporous film has a molecular weight of 5 × 1.
It is necessary to be an ultra-high molecular weight polyethylene of 0.05 to 7 × 10 6. If the molecular weight is too high, molding into a film becomes difficult, and if it is too low, the film strength decreases,
A high porosity microporous film having excellent moisture permeability and waterproofness cannot be obtained.

The polyethylene may be a copolymer of a small amount, preferably 5 mol% or less, of propylene, butene, pentene, hexane, 4-methylpentene-1, octene and the like. 25% by weight
The following polypropylene, polybutylene, ethylene-propylene copolymer and the like may be contained. In addition, the polyethylene may contain commonly used additives such as a stabilizer, a colorant, a flame retardant, and an antistatic agent.

Further, the ultra high molecular weight polyethylene microporous film used in the present invention has a pore size of 0.1 to 0.1.
It is necessary to have many 2.0 μm micropores. If the pore size is too small, sufficient moisture permeability cannot be obtained, and if it is too large, the waterproofness becomes poor.

In order to manufacture a microporous film having many such micropores, for example, a solution (concentration: 2 to 30% by weight) of polyethylene dissolved in a solvent such as decalin is extruded from a slit die to form a gel. A method of forming a film, evaporating the solvent in the gel film, and then stretching the film is used.

A microporous film made of such ultrahigh molecular weight polyethylene and a method for producing the same are described in, for example, JP-A-2-232242 and JP-A-5-222.
-98065, JP-A-5-239246, etc., and are well known.

Such a microporous film is usually
It is in the form of fibrillated non-woven fabric with a basis weight of 7 to 15
g / m2, porosity is about 60 to 90%, air permeability (J
(Measured according to IS 1076-79A method)
It is preferably about 3.0 cc / cm2 / sec. Further, it is preferable to improve the interlayer strength of the fibrillated non-woven fabric by thermal calendering from the viewpoint of improving durability.

On the other hand, as a cloth to be bonded to a microporous film made of ultra-high molecular weight polyethylene, a woven fabric, a knitted fabric, a non-woven fabric and the like can be used, and a woven fabric is particularly preferable. Can be appropriately selected, but polyester is preferable. In the case of cloth, the basis weight is 25 to 150 g / m.
2. The air permeability (measured in accordance with JIS 1076-79A method) is preferably about 0.5 to 3.0 cc / cm2 / sec.

In order to laminate and bond a microporous film made of ultra-high molecular weight polyethylene and a fabric, it is necessary to use partial bonding so that the porous portion of the microporous film is not closed as much as possible by bonding. is there. In this case, the ratio of the bonding portion to the total lamination area is preferably 30 to 60%. Especially,
It is preferable that they are adhered in a dot shape, a line shape or a mesh shape. As described above, in order to bond in a dot shape, a line shape, and a mesh shape, a method of applying and bonding an adhesive with a gravure roll engraved in a predetermined shape, a hot melt adhesive in a thread shape,
For example, a method of injecting into a powder form and performing thermocompression bonding can be used.

[0018]

The present invention will be described in more detail with reference to the following examples. The porosity, air permeability, water permeability, and water pressure resistance were measured as follows.

(1) Porosity Density of starting material (ρ0) and film density after molding (ρ)
Is calculated based on the following equation.

[0020]

(Equation 1)

(2) Air permeability Measured according to JIS 1076-79A method.

(3) Water permeability Measured according to JISZ208.

(4) Water pressure resistance JIS L1092-1977.5.1.2. The measurement was performed according to the method B (high water pressure method).

Example 1 An epoxy hot melt adhesive was sprayed on one side of a polyethylene terephthalate taffeta woven fabric having a basis weight of 110 g / m 2 and an air permeability of 1.3 cc / cm 2 / sec. Porosity 85%, basis weight 10
A polyethylene microporous film (molecular weight: 2 × 106, pore size: 1.0 μm) having a g / m 2 of 0.5 cc / cm 2 / sec and a gas permeability of 0.5 g / m 2 was laminated and calendered at 180 ° C. for adhesion. The ratio of the bonded portion to the total lamination area is 4
It was 0%.

The water permeability of the obtained laminated fabric is 18,000.
g / m2 / 24 hours, water resistance is 25,000 mm-H2
O was excellent in dimensional stability and moisture permeability and waterproofness.

Comparative Example In Example 1, a porosity of 50% was used instead of the polyethylene microporous film.
When a porous polytetrafluoroethylene film having an air permeability of 2.0 cc / cm2 / sec and a thickness of 40 μm was used, the water permeability of the obtained laminated fabric was 9,000 g / m2 /
For 24 hours, the water pressure resistance was 15,000 mm-H2O, and the moisture permeability and waterproofness were inferior to those of Example 1.

Incidentally, an attempt was made to obtain a porous polytetrafluoroethylene film having the same porosity as that of the polyethylene microporous film used in Example 1, but the strength was lowered and could not be obtained.

[Example 2] A urethane-based adhesive was linearly engraved on one surface of a nylon tricot knitted fabric having a basis weight of 80 g / m2 and an air permeability of 2.0 cc / cm2 / sec with a gravure roll carved linearly. And porosity of 80%,
Polyethylene microporous film having a basis weight of 12 g / m 2 and an air permeability of 1.0 cc / cm 2 / sec (molecular weight: 8 × 10
5, a hole diameter of 1.5 μm) and calendered at 160 ° C. for bonding. The ratio of the bonded portion to the total laminated area was 50%.

The water permeability of the obtained laminated fabric is 15,000.
g / m2 / 24 hours, waterproof pressure is 21,000mm-H2
O was excellent in dimensional stability and moisture permeability and waterproofness.

[0030]

According to the present invention, it is possible to provide a fabric which is inexpensive and has excellent dimensional stability and moisture permeability and waterproofness.

Claims (4)

[Claims] 1. An ultrahigh molecular weight polyethylene having a molecular weight of 5 × 105 to 7 × 10 6 and a pore size of 0.1 to 2.0 μm.
A moisture-permeable waterproof fabric characterized by laminating and bonding a fabric to a microporous film having a large number of micropores by partial bonding. 2. The fabric according to claim 1, wherein the fabric is a polyester fabric.
The moisture-permeable waterproof fabric described in the above. 3. The moisture-permeable and waterproof fabric according to claim 1, wherein the partial adhesion is in the form of dots, lines or meshes. 4. The moisture-permeable and waterproof fabric according to claim 1, wherein the microporous film and the fabric are dry-laminated by partial adhesion using a hot melt adhesive.