JPH1161648A - Moisture-permeable and waterproof fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a moisture-permeable and waterproof fabric excellent in wearing properties without becoming stuffy in clothes even by operations or the like in a severe environment by forming a urethane resin film containing a microporous membrane on the surface of a fiber fabric and providing prescribed moisture permeability, a prescribed amount of dew condensation and prescribed water-resistant pressure to the urethane film. SOLUTION: This moisture-permeable and waterproof fabric is obtained by forming a urethane resin film, having, e.g. >=170 % moisture content, containing a fine particulate aluminum oxide having <=20 nm particle diameter and comprising a one-part type ester-based polyurethane resin and a low- polymerization degree polyurethane resin containing a microporous membrane on at least one side of a fiber fabric. The fabric has >=15,000 g/m<2> .24 hr moisture permeability according to a potassium acetate method, >=5 g/m<2> .hr amount of dew condensation and >=8,000 mmH2 O water-resistant pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a moisture-permeable waterproof fabric, and more particularly to a moisture-permeable waterproof fabric having excellent moisture permeability and anti-condensation properties.

[0002]

2. Description of the Related Art Conventionally, in order to obtain a moisture-permeable waterproof fabric,
It is well known that a urethane resin solution is coated on a fiber fabric using a knife over roll coater or other coating machine and solidified in water to form a microporous film mainly composed of urethane resin. . Various techniques have been developed for improving the function of the moisture-permeable waterproof fabric. The purpose of the technique is to improve the moisture permeability by the JIS L 1099 calcium chloride method (A-1 method) and simultaneously increase the water pressure resistance. Was that. This is to obtain a more comfortable and reliable moisture-permeable waterproof fabric.

However, the Journal of the Fiber Society of Japan, Vol. 41,
No. 11, p. 415 to 425 (1985) point out the following problems in measuring moisture permeability by the calcium chloride method. There is an air layer between the sample to be measured and the source of the vapor and on the side where the vapor is released and diffused, which serves as a barrier to the movement of the vapor.

Since the distance between calcium chloride and the sample to be measured changes with time due to moisture absorption, the amount of vapor transmission decreases with the passage of time. Since the capacity of the hygroscopic agent is small, the measured value is almost the same in the case of a highly moisture-permeable material, and the material cannot be differentiated. Also, when evaluating moisture permeability in relation to comfort,
Conventionally, the calcium chloride method such as the JIS L 1099 A-1 method has been adopted as an evaluation method, but the Hohenstein Institute of Germany has established a comfort evaluation method using a simulated skin model (skin model). Since then, the pseudo skin model has been evaluated as a practical evaluation method of comfort, and has been established as ISO11092. Then, according to the Journal of the Society of Fiber Science, the moisture permeability by moisture permeation resistance R _et and JIS L 1099 B-1 method potassium acetate method by skin model The German Hohenstein Institute has established a negative correlation relationship It is shown.

[0005] Therefore, as a practical evaluation method of comfort, I
Since SO11092 is recognized, the JIS L-1099 B-1 method, which has a similar correlation, is also considered to be effective as a means for evaluating actual wearing comfort. On the other hand, calcium chloride method A-1
There is no correlation between the moisture permeability in the potassium acetate method and the potassium acetate method B-1 method. Here, the characteristic of the measurement in the potassium acetate method is as follows. The sample to be measured is in direct contact with liquid water, and in the potassium acetate method, the process from the diffusion or dissolution of the water to the sample to be evaporated to the evaporation is performed. You are measuring speed.

Therefore, in order to obtain a high measurement result in such a measuring method, it is necessary to have a chemical structure and a microporous structure of a resin which can easily transfer liquid moisture. In addition, when the ambient temperature is lowered during actual wearing, water drops are generated and adhere to the inside of the clothes. In such a state, even if it shows remarkable moisture permeability (calcium chloride method) at a certain temperature, if there is a temperature difference between the outside air and the inside of the clothes, water droplets will be generated, and the dew condensation phenomenon will occur. However, there is a problem that stickiness and body temperature are lost.

As a simulation test of this dew condensation phenomenon, for example, a hermetically closed cover is placed on a beaker containing hot water of 50 ° C. with the urethane surface of the sample to be measured facing down, and a 10 ° C., 65% R.C.
H. When evaluating the dew condensation by measuring the amount of water adhering to the film surface by leaving it in the atmosphere (reducing the temperature of the air), in order to control the dew condensation, the adhering water droplets are quickly absorbed. Thus, the ability to discharge the garment out of the garment is required, and in this case, the magnitude of the moisture permeability by the potassium acetate method greatly gives true comfort in the garment. High moisture permeability by the calcium chloride method alone is not effective in suppressing condensation.

[0008] As described above, if the purpose is to improve the water pressure resistance simultaneously with the improvement of the moisture permeability by the conventional calcium chloride method, the improvement of the moisture permeability by the potassium acetate method, which is related to the true comfort, is required. Unlike the case of aiming at the above, the obtained moisture-permeable waterproof fabric was hardly said to be comfortable when actually worn. In addition, many urethane resins that can obtain a commercially available microporous film are ester-based polyurethane resins that are hydrophobic, and this urethane resin has a hydrophilic or hydrophobic fine particle additive, for example, fine silica, The addition of cellulose powder is known, and the addition of fine particles is effective in improving moisture permeability (the potassium acetate method and the calcium chloride method).

For example, JP-A-6-272168 discloses that
A polyurethane-based synthetic polymer solution containing 1% or more of an inorganic powder having an average particle diameter of 1 μm or less and an N, N-dimethylformamide adsorption amount of 200 ml / 100 g or more is coated on a fabric by a wet coating method. A moisture-permeable waterproof fabric having a moisture permeability (calcium chloride method) of 7,000 g / m ² · 24 hours or more and a water pressure resistance of 0.6 kgf / m ² or more is shown. When the moisture permeability of the moisture-permeable waterproof fabric obtained by this method is measured by the potassium acetate method, the moisture permeability is improved as compared with the case where no inorganic powder is added, but it is 10,000 g / m ² · 24 hr or less. It cannot obtain a moisture permeability of 15,000 g / m ² · 24 hr or more.

Furthermore, the addition of fine particles is effective in improving moisture permeability, but generally involves a decrease in water pressure resistance, a decrease in washing durability, and a decrease in peel strength. It was difficult to satisfy. As a method of improving moisture permeability by the potassium acetate method, there is a method of making a urethane resin hydrophilic. As a method, a hydrophilic group such as a polyethylene glycol group or a fluoronic group which is a copolymer of ethylene glycol and propylene glycol is used as the urethane resin. Is considered to be effective as a means for hydrophilization, but when coagulated with water, the coagulation rate is slowed down, forming a microporous structure. Not suitable for. In general, when such a polyether-type urethane resin is coagulated in water, it is hardly used because a coherent, nonporous structure is easily formed without forming a porous structure. .

Further, in order to obtain higher moisture permeability and water pressure resistance, Japanese Patent Publication No. 33592/1993 provides a nonporous film on a microporous resin film obtained by a wet method.
Water pressure 25,000mmH ₂ O or more, moisture permeability 3,000g
Although a moisture-permeable waterproof fabric obtained from a urethane resin having a flow rate of / m ² · 24 hrs or more is shown, the moisture-permeable waterproof fabric cannot provide comfortable moisture permeability even though high waterproofness can be obtained. That is, a Japanese Patent Publication No. 33592/1992 is formed on a wet microporous membrane.
In addition to the resin and hydrophobic urethane resin disclosed in the above, even when a hydrophilic urethane resin is coated with a normal urethane resin, the moisture permeability (potassium acetate method) is rather reduced, and the water resistance is lowered. Is improved, but comfort is reduced.

[0012]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a highly reliable transparent material that does not cause stuffiness or water leakage even when working in an environment with severe wind and rain or performing heavy exercise. An object of the present invention is to provide a moisture-permeable waterproof fabric having moisture and waterproof properties.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a moisture-permeable waterproof fabric in which a urethane resin film including a microporous film is formed on at least one surface of a fiber fabric, wherein a potassium acetate method is used. 15,000g /
m or ² · 24 hr or more, the condensation amount is equal to or less than 5 g / m ² · hr, provides the moisture-permeable waterproof fabric, characterized in that water pressure is 8,000mmH ₂ O or more.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION As a material of a fiber fabric useful in the present invention, synthetic fibers such as polyester, nylon, acrylic and rayon; natural fibers such as cotton, hemp and wool; and mixed or mixed fabrics thereof. And is not particularly limited. In addition, their form may be any form such as a woven fabric, a knitted fabric, and a nonwoven fabric.

The moisture-permeable waterproof fabric of the present invention has a microporous membrane. Conventionally, an N, N-dimethylformamide solution of a urethane resin is applied on a woven fabric to form a microporous urethane resin. It is known to form a moisture-permeable waterproof fabric by applying a membrane, and improvement means have been proposed for improving the moisture permeability (calcium chloride method) and the water pressure resistance.

However, as described above, no proposal has been made for a means for improving the moisture permeability by the potassium acetate method for evaluating actual wearing comfort. Regarding the permeability of the substance of the microporous membrane, it is natural that the microporous structure is involved. In the field of microfiltration membranes, microporous hollow fibers are used. It is described that the ratio, pore size, distribution, thickness, and the like are related (Journal of the Textile Society of Japan, Vol. 49, No. 6, p-20).
0 (1993)).

Regarding the moisture permeability, naturally, it is assumed that the structure of the urethane resin microporous membrane has a high porosity, and that a structure in which the pores communicate with each other provides high moisture permeability, and various proposals have been made. ing. In one method for obtaining a microporous membrane useful in the present invention, a urethane resin dissolved in N, N-dimethylformamide is placed in water, whereby the water is replaced with N, N-dimethylformamide to replace the urethane resin. Coagulates in water, and the water is eventually dried to form pores, resulting in a microporous membrane. The amount of water contained in the microporous membrane (water content) Paid attention to the fact that it should be proportional to the porosity, and found that there is a correlation between the water content and the moisture permeability by the potassium acetate method. That is, they found that the higher the moisture content of the microporous membrane, the higher the moisture permeability by the calcium acetate method.

When the water content of the microporous membrane is 170% or more, the moisture permeability by the potassium acetate method is 15,000 g / m 2.
Will be ² · 24hr or more, a comfortable waterproof fabric can be obtained.
There is no clear correlation between the water content and the moisture permeability by the calcium chloride method. This microporous film has 1
With micropores of less than μm
It has m holes, and a fine hole of about 1 μm is further formed in the wall thereof, and has a structure communicating with each other.

As a preferable means for obtaining a microporous membrane having a water content of 170% or more, a microporous membrane has a particle diameter of 20 nm.
It is preferable that the microporous film contains the following particulate aluminum oxide, and is made of a one-pack type ester-based polyurethane resin and a low polymerization degree ester-based polyurethane resin. The finely divided aluminum oxide having a particle diameter of 20 nm or less used in the present invention preferably has a specific surface area of about 100 m ² / g, and the addition amount thereof is 0.5 to 30 parts by weight based on the urethane resin solid content.
Preferably, the amount is 3 to 15 parts by weight. This makes it possible to increase the moisture permeability, improve the initial water pressure resistance, and maintain the water pressure resistance after washing.

For forming a microporous membrane having a water content of 170% or more, a one-pack type polyurethane resin is used, which is a known one-pack type ester-based polyurethane resin or a one-pack type ester-based polyurethane resin and is modified with an amino acid. And fluorine-containing ones, and are not particularly limited. In addition to these one-component ester-based polyurethane resins, in order to improve water pressure resistance and peel strength,
It is preferable to blend a low polymerization degree ester-based polyurethane resin. Here, the low polymerization degree ester-based polyurethane resin is a known ester-based polyurethane resin having a molecular weight of 50,000 or less.

These urethane resins have a solid content of 25 to 40.
% Of a polar organic solvent solution, and the compounding ratio thereof (one-pack type ester-based polyurethane resin: low polymerization degree ester-based polyurethane resin) is preferably in the range of 100: 5 to 50:50 (weight ratio). . Outside this range, the moisture permeability is high, but the water pressure is low and the peel strength is low, or the product is high in the water pressure and peel strength but low in moisture permeability, resulting in low practicality.

Next, a method for forming a microporous film will be described. Before applying the urethane resin solution, a water-repellent treatment or a calendering treatment is performed on the fiber fabric, if necessary, in order to prevent the urethane resin solution from excessively permeating the fiber fabric. Next, the urethane resin solution is applied to at least one surface of the fiber cloth. N, N-dimethylformamide, dimethylacetamide, and the like are used as polar organic solvents generally used in the urethane resin solution. An isocyanate-based crosslinking agent, a white pigment, other known additives, and the like may be further added to the urethane resin solution.

As a coating method, a urethane resin solution is applied to the fiber cloth by a known means such as a knife over roll coater, and then dipped in water to solidify the resin.
A microporous membrane is formed. The coagulation bath at this time is preferably water or an aqueous solution of a polar organic solvent, and may be performed at a water temperature of 5 to 60 ° C. Next, wash with hot water for 20 to 8 to remove the solvent.
The drying is performed at 0 ° C., and the drying is performed at 100 to 130 ° C. using an air oven or a hot cylinder.

The thickness of the microporous membrane is preferably about 10 to 40 μm, and if it is less than 10 μm, the water pressure resistance is low, and
At 0 μm or more, the texture becomes hard. Further, in the moisture-permeable waterproof fabric of the present invention, in the urethane resin film, a nonporous film having a water swelling degree of 50% or more is formed on the microporous film from a two-component polyurethane resin. And water-permeable waterproof fabrics. Such a moisture-permeable waterproof cloth can be used for the purpose of obtaining higher water pressure resistance and higher surface strength than those having only a microporous urethane resin film. When used under severe conditions such as mountainous use, such high waterproof performance and comfort are required.

In a non-porous film, the movement of water vapor passes through the film through the process of absorption of moisture → diffusion → evaporation from the film. The potassium method) shows a high value, but as a guide, the weight ratio (water swelling degree) that absorbs water after immersing the film in water for a predetermined time is adopted here, and this is used to determine the moisture permeability by the potassium acetate method. Are found to be correlated.

When a nonporous membrane having a water swelling degree of less than 50% is provided, the moisture permeability is lower than when only a microporous membrane is used. However, when a nonporous membrane having a water swelling degree of 50% or more is provided, the urethane resin film having the microporous membrane and the nonporous membrane has more potassium acetate than the microporous membrane alone. Instead, the moisture permeability by the method is improved.

The urethane resin used here is a two-pack type polyurethane resin modified with a polyethylene glycol group or the like to make it hydrophilic. The solvent of the urethane resin contains N, N-dimethylformamide in a range of 10% by weight or less (N, N-dimethylformamide may not be contained at all). Many one-part hydrophilic urethane resins contain N, N-dimethylformamide in a solvent of the resin solution in an amount of 10% by weight or more,
Dissolves the already formed microporous urethane resin film, causing a decrease in moisture permeability and hardening of the texture,
Not preferred. Of course, even with a hydrophilic two-pack type polyurethane resin, the same problem occurs if a urethane resin solution containing N, N-dimethylformamide in an amount of 10% by weight or more in the total solvent is used.

As a method for forming a nonporous membrane, a two-pack type polyurethane resin solution is applied on a microporous membrane using a knife coater or a gravure coater, and dried. Examples of the solvent for the two-pack type polyurethane resin solution include N, N-dimethylformamide, methyl ethyl ketone, toluene, ethyl acetate, and isopropyl alcohol. Using these solvents, N, N-
The proportion of dimethylformamide in the solvent is 10% by weight or less.

An isocyanate crosslinking agent, inorganic or organic fine powder such as calcium carbonate, colloidal silica, cellulose, protein, PMMA resin and the like may be added to the two-pack type polyurethane resin solution. At this time, the thickness of the resin film is preferably about 0.1 to 10 μm.
The higher the coating amount, the higher the water pressure resistance.

As a coating method, a knife coater or a gravure coater can be used. The applied two-pack type polyurethane resin solution is placed in an air oven etc. for 1
Drying at about 00 to 160 ° C. yields a nonporous membrane.
Next, a known water-repellent treatment is performed using a fluorine-based water-repellent, a silicon-based water-repellent, etc., wrinkles are removed at 100 to 150 ° C., and a finishing set is performed for standard adjustment, whereby a moisture-permeable waterproof fabric is obtained. Can be If necessary, a paper treatment or the like may be performed after the water-repellent treatment.

As described above, the moisture-permeable waterproof fabric in which the urethane resin film is composed of the two layers of the microporous film and the water-swellable nonporous film layer has improved waterproof performance without lowering the moisture permeability. Moisture permeability of 15,000 g / m ² · by potassium acetate method
It has a performance of 24 hours or more and has a water resistance of 20,000.
0 mmH ₂ O or more.

[0032]

As described above, the moisture-permeable waterproof fabric according to the present invention has excellent water vapor transmission performance (moisture permeability by the potassium acetate method), so that water vapor generated from the body can be quickly released to the outside of the clothes and the inside of the clothes. Also discharges water droplets generated due to the difference between the outside temperature and the outside temperature, prevents water leakage because it has higher waterproof performance, and works in harsh environments,
Even when exercising, the inside of the clothes does not become stuffy or sticky, enabling work and exercise in a comfortable working environment.

[0033]

The present invention will be further described below with reference to examples. In the examples, "parts" indicates parts by weight. The evaluation of the coating described in the present specification was based on the following method. A) Measurement of moisture content of microporous membrane Tyvek (Dupont PP nonwoven fabric, thickness 0.16 mm)
A urethane resin solution for obtaining a microporous film having a thickness of 0.
It was coated with 12 mm, coagulated with water, and washed with 50 ° C. water for 5 minutes. The microporous membrane formed on the nonwoven fabric was cut off, peeled off from the nonwoven fabric, and weighed while still containing water (W ₁ ). Further, the weight of the microporous membrane after drying was measured (W ₀ ). The water content was calculated by the following equation.

[0034]

(Equation 1)

B) Degree of water swelling of the non-porous membrane A urethane resin solution is applied on a release paper to a thickness of 0.08 mm, dried at 120 ° C. for 3 minutes, and after 18 hours, 5 cm
It was cut into a size of × 5 cm, the nonporous membrane was peeled off from release paper, and the weight was measured (w ₂ ). Next, the nonporous membrane was immersed in tap water for 5 minutes, taken out, weighed (w ₃ ), and the water swelling degree was calculated by the following equation.

[0036]

(Equation 2)

1) Moisture permeability JIS L 1099 A-1 method (calcium chloride method)
And B-1 (potassium acetate method). However, the display was converted into 24 hours. 2) Water pressure resistance Measured according to JIS L 1092 B method. The washing method for measuring the water pressure retention rate after washing is described in J.
Using IS L 0217 103 method, before washing and 10
The water resistance after the first washing was compared. 3) Peel strength Measured according to JIS K 6328. 4) Condensation 500 ml of hot water at 40 ° C contains 500 ml of condensation.
The beaker is covered with a sample so that the resin film surface (in the case where both surfaces are made of a fiber material, the inside when used in clothes, etc.) is inside the beaker, and is fixed with a rubber band. 10 of this beaker
It is left for 1 hour in a thermo-hygrostat at 60 ° C. and 60% RH. One hour later, the amount of water droplets adhering to the resin film surface was measured to determine the amount of dew condensation, and the unit was converted to g / m ² · hr. Example 1 The following urethane resin solution was prepared. Mixed resin solution for microporous membrane One-part ester polyurethane resin (solid content 30%) 70 parts Low polymerization degree ester polyurethane resin (solid content 40%) 30 parts (molecular weight 40,000) N, N-dimethylformamide 40 parts Particulate aluminum oxide 3 parts (Average particle size: 13 nm, specific surface area: 100 g / m ² ) L-6519 (white pigment, manufactured by Dainippon Ink) 3 parts Coronate HL 1 part (Nippon Polyurethane isocyanate) This resin solution The water content of the resulting microporous membrane was 180%.

Using this urethane resin solution, a moisture-permeable waterproof fabric was processed in the following procedure. A polyester woven fabric (75 denier, 72 filaments) with a density of 180 yarns / inch and 94 yarns / inch in width is scoured and dyed by a conventional method and dyed by Asahigard AG710 (fluorine-based water repellent). The fabric was impregnated with a 5% aqueous solution of Asahi Glass Co., Ltd., squeezed with a mangle, dried, and then heat-treated at 150 ° C. for 30 seconds.

Next, the mixed resin solution was coated using a knife over roll coater. This is 2
The mixture was introduced into water at 0 ° C., solidified for 2 minutes, washed with water at 50 ° C. for 5 minutes, and dried in an air oven at 130 ° C. to obtain a microporous film having a resin film thickness of 40 μm. Next, a water repellent treatment was performed using Asahigard AG690 (a fluorine-based water repellent, manufactured by Asahi Glass Co., Ltd.), and a finishing set was performed at 140 ° C.
Paper treatment was performed to obtain a moisture-permeable waterproof fabric. Table 1 shows various physical properties of the obtained moisture-permeable waterproof fabric. Comparative Example 1 A moisture-permeable waterproof fabric was obtained in the same manner as in Example 1 except that the following urethane resin solution was used.

Chris Bon 8006 (urethane resin manufactured by Dainippon Ink) 100 parts N, N-dimethylformamide 40 parts L-6519 (white pigment, manufactured by Dainippon Ink) 3 parts Thylsia 740 (manufactured by Fuji Silysia, silica) 9 parts (average) Particle size: 3.5 μm, specific surface area: 700 g / m ² ) 1 part of coronate HL (Nippon Polyurethane Isocyanate) The water content of the microporous membrane obtained from this resin solution was 130%.

Table 1 shows various physical properties of the obtained moisture-permeable waterproof cloth.
It writes in. Comparative Example 2 A moisture-permeable waterproof fabric was obtained in the same manner as in Example 1 except that the following urethane resin solution was used. One-part ester polyurethane resin (solid content 30%) 70 parts Low polymerization degree ester polyurethane resin (solid content 40%) 30 parts (molecular weight 40,000) N, N-dimethylformamide 40 parts Fine-particle hydrophobic silica 3 Part (average particle size: 16 nm, specific surface area: 110 g / m ² ) L-6519 (white pigment, manufactured by Dainippon Ink) 3 parts Coronate HL 1 part (Nippon Polyurethane Isocyanate) Microporous obtained from this resin solution The water content of the membrane was 160%.

Table 1 shows various physical properties of the obtained moisture-permeable waterproof fabric.
It writes in. Comparative Example 3 A moisture-permeable waterproof fabric was obtained in the same manner as in Example 1 except that the following urethane resin solution was used. One-part ester urethane resin (solid content 30%) 70 parts Low polymerization degree ester polyurethane resin (solid content 40%) 30 parts (molecular weight 40,000) N, N-dimethylformamide 40 parts Sycyria 740 (manufactured by Fuji Silysia) , Silica) 9 parts (average particle size: 3.5 μm, specific surface area: 700 g / m ² ) L-6519 (white pigment, manufactured by Dainippon Ink) 3 parts Coronate HL 1 part (Nippon Polyurethane isocyanate) From this resin solution The water content of the obtained microporous membrane was 150%.

Table 1 shows various physical properties of the obtained moisture-permeable waterproof fabric.
It writes in.

[0044]

[Table 1]

Example 2 A urethane resin for obtaining a microporous membrane was blended according to the following formulation. Mixed resin solution for microporous membrane One-part ester urethane resin (solid content 30%) 70 parts Low polymerization degree ester urethane resin (solid content 40%) 30 parts (molecular weight 40,000) N, N-dimethylformamide 40 parts Particulate aluminum oxide 3 parts (Average particle size: 13 nm, specific surface area: 100 g / m ² ) L-6519 (white pigment, manufactured by Dainippon Ink) 3 parts Coronate HL 1 part (Nippon Polyurethane Isocyanate) This resin solution The water content of the resulting film was 180%.

Using this urethane resin solution, a moisture-permeable waterproof fabric was processed in the following procedure. Nylon taffeta woven fabric (warp 70 denier / 68 filament, weft 70 denier / 68 filament) with a density of 123 warp /
Inch, 87 horizontal / 87 inch plain woven fabrics are scoured and dyed by a conventional method, and the fabric is impregnated with a 5% aqueous solution of Asahigard AG710 (fluorine-based water repellent, manufactured by Asahi Glass Co., Ltd.). After squeezing and drying, it was heat-treated at 150 ° C. for 30 seconds.

Next, the mixed resin solution was coated using a knife over roll coater. This is 2
The mixture was introduced into water at 0 ° C., solidified for 2 minutes, washed with water at 50 ° C. for 5 minutes, and dried in an air oven at 130 ° C. to obtain a microporous film having a resin film thickness of 40 μm. Further, a nonporous urethane film was provided on the obtained microporous urethane film by the following procedure.

First, the following urethane resin solution for a nonporous membrane was prepared. Two-part polyurethane resin (solid content 30%) 100 parts Toluene 50 parts Isopropyl alcohol 50 parts Coronate HL 1 part (Nippon Polyurethane Isocyanate) The water swelling degree of the coating obtained from this resin solution was 60%.

The urethane resin solution was applied at a rate of 50 g / m ² using a knife coater and dried at 120 ° C. to obtain a nonporous membrane. Next, Asahi Guard AG690
(A fluorine-based water repellent, manufactured by Asahi Glass Co., Ltd.), water-repellent treatment, finishing setting at 140 ° C., and paper treatment to obtain a moisture-permeable waterproof fabric. Table 2 shows various physical properties of the obtained moisture-permeable waterproof fabric. Comparative Example 4 A moisture-permeable waterproof fabric was obtained in the same manner as in Example 2, except that the following urethane resin solution for a nonporous membrane having a water swelling degree of the obtained film of 5% was used. 100 parts of urethane resin solution for nonporous membrane Y-210 (manufactured by Dainichi Seika, one-pack type urethane resin for moisture permeability) 80 parts of methyl ethyl ketone Various physical properties of the obtained moisture-permeable waterproof fabric are shown in Table 2.

[0050]

[Table 2]

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[Procedure amendment]

[Submission date] August 27, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 5

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0027

[Correction method] Change

[Correction contents]

The urethane resins used here is a two-pack type of modified with polyethylene glycol group, Ri polyurethane resins der you hydrophilic, it is of no yellowing
Is preferred . The solvent of this urethane resin is N, N-
It contains dimethylformamide in a range of 10% by weight or less (N, N-dimethylformamide may not be contained at all). Many of the one-part hydrophilic urethane resins contain N, N-dimethylformamide in the solvent of the resin solution in a range of 10% by weight or more, and dissolve the already formed microporous urethane resin film. This may cause a decrease in moisture permeability and a hardening of texture, which is not preferable. Of course, even if it is a hydrophilic two-component polyurethane resin,
The same problem occurs when a urethane resin solution containing N, N-dimethylformamide in an amount of 10% by weight or more in the total solvent is used.

Claims (5)

[Claims] 1. A moisture-permeable waterproof fabric in which a urethane resin film containing a microporous film is formed on at least one surface of a fiber fabric, wherein the moisture permeability by the potassium acetate method is 15,000 g.
/ M ² · 24 hr or more, a dew amount of 5 g / m ² · hr or less, and a water pressure resistance of 8,000 mmH ₂ O or more. 2. The moisture-permeable waterproof fabric according to claim 1, wherein the water content of the microporous membrane is 170% or more. 3. The transparent porous membrane according to claim 1, wherein the microporous membrane contains fine-particle aluminum oxide having a particle size of 20 nm or less, and is composed of a one-pack type ester-based polyurethane resin and a low polymerization degree ester-based polyurethane resin. Moist waterproof fabric. 4. A microporous membrane is provided with a nonporous membrane made of a two-component polyurethane resin and having a water swelling degree of 50% or more, and has a moisture permeability of 15,000 by a potassium acetate method.
0 g / m ² · 24 hours or more, and the amount of dew condensation is 5 g / m ² ·
and at hr or less, and water pressure resistance 20,000mmH ₂ O or more, moisture-permeable waterproof fabric of claim 1 wherein. 5. The two-pack type polyurethane resin is a non-yellowing type, and the solvent composition contains 10% by weight of a polar organic solvent.
The moisture-permeable waterproof fabric according to claim 4, which is: