JPS61138778A - Breathable waterproofing cloth and its production - Google Patents

Abstract

PURPOSE:A breathable water-proofing cloth that is made by bonding a porous membrance of a specific polyaminoacid polyurethane resin which has microcells connecting one another through micropores to one surface of a water-repelling fiber cloth. CONSTITUTION:A synthetic fiber cloth which has been treated with a water- repelling gent is coated, on one surface, with a resin solution containing a polyaminoacid urethane resin with an absorptivity ratio of 0.4-2.0 at wave numbers of 3290cm<-1> and 2950cm<-1> in infrared absorption spectrum, an isocyanate, a microprore-forming agent such as an anionic surfactant, and a polar organic solvent such as dimethylformamide and coagulated by the wet process to form a porous membrane which has microcells connecting one another through fine pores and a number of fine pores connecting to microcells on the surface of the membrane. Thus, a water-proofing cloth with high breathability is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing a fabric that simultaneously has three functions of waterproofness and moisture permeability, and has excellent cold resistance properties.

(Conventional technology) Generally, moisture permeability and waterproofness are mutually contradictory functions, but
Waterproof fabrics with excellent moisture permeability are obtained by forming numerous continuous fine pores that allow water vapor to escape in the coating resin film during dry or wet coating.

Polyurethane elastomer is generally preferably used as the coating resin during these dry or wet coating processes in terms of film strength, rubber elasticity, and flexibility. However, in the case of breathable waterproof fabric made from polyurethane elastomer, it is made based on a balance between waterproof performance and moisture permeability, so its waterproof performance is JIS L-.
1,500m5+ (under water column) with 1096 water pressure measurement
For the above fabrics, the humidity is 4,000 to 5,000.
g/rd・24hrs (measured by JIS Z-0208).Currently, only about 24hrs (measured by JIS Z-0208) can be obtained.Furthermore, when used in extremely cold areas with temperatures below -20℃, the fabric becomes extremely hardened and the film deteriorates. It had the drawbacks of high bending fatigue and decreased waterproofness. The present inventors have discovered that among the drawbacks of conventional moisture-permeable waterproof fabrics made of polyurethane elastomers,
Patent application filed in 1983 for a manufacturing method for a moisture-permeable waterproof fabric that greatly improves the level of moisture permeability and allows for smooth control of humidity inside clothing due to sweating when working in the rain or exercising.
- Proposed in No. 10853. That is, this method uses a polyamino acid urethane resin and a special micropore-forming agent to control the microcells and pore diameter of a porous membrane to produce a highly moisture-permeable waterproof fabric by a wet coating method. However, when the moisture-permeable waterproof fabric obtained by this method is used in extremely cold regions, as with conventional moisture-permeable waterproof fabrics made from polyurethane elastomers, the curing at low temperatures is significant and the waterproofness decreases due to single-wave fatigue. It had major drawbacks.

(Problem to be solved by the invention) The present invention was made in view of the above-mentioned current situation.

The object of the present invention is to obtain a moisture-permeable waterproof fabric that has a good balance between waterproofness and moisture permeability, and has good cold resistance in extremely cold regions.

(Means and effects for solving the problem) As a result of intensive research, the present inventors have discovered that there is a correlation between cold resistance characteristics and the ratio of absorbance at a specific wavelength of an infrared absorption spectrum, and based on this knowledge, As a result of further studies, we have arrived at the present invention. That is, 1 the present invention is based on the wave numbers 3290 cm-' and 2950 cm-' in the infrared absorption spectrum.
A film made of a polyamino acid urethane resin having an absorbance ratio of 0.4 to 2.0, the film has microcells interconnected by pores in the thickness direction of the film, and "A moisture-permeable waterproof fabric with excellent cold resistance, characterized by having a porous membrane having numerous micropores communicating with the microcells on its surface bonded to one side of a T8 aqueous fiber fabric" and "Infrared absorption spectrum wave number 329 at
The ratio of absorbance at 0cm-' and 2950c+w-' is 0.4
A resin solution consisting of a polyamino acid urethane resin in the range of ~2.0, an isocyanate compound, a micropore-forming agent, and a polar organic solvent is applied to one side of a fiber fabric, then immersed in water, washed with hot water, and dried. tR the coated fabric
``Production method of moisture-permeable waterproof fabric with excellent cold resistance characterized by water treatment'' and ``The ratio of absorbance at wave numbers 3290 cm-' and 2950 cm-' in the infrared absorption spectrum is in the range of 0.4 to 2.0. It is characterized by applying a resin solution consisting of a certain polyamino acid urethane resin, an isocyanate compound, a micropore forming agent, and a polar organic solvent to one side of a water-repellent fiber fabric, then immersing it in water, washing it with hot water, and drying it. ``Method for producing moisture-permeable waterproof fabric with excellent cold resistance''
The main points are as follows. The present invention will be explained in detail below. The infrared absorption spectrum referred to in the present invention is obtained by using an infrared spectrophotometer to separate the wavelengths from the near-infrared region to the far-infrared region using a prism, etc., and then applying the separated light to a substance. A large number of relatively narrow absorption bands due to molecules appear, and it is useful for the identification of compounds, especially for the qualitative and quantitative analysis of functional groups, and is mainly used for the qualitative and quantitative analysis of organic substances. Polyamino acid urethane resin (hereinafter referred to as PAU resin) is a copolymer of amino acids and urethane, and the present inventors have investigated the composition of the copolymer to improve the physical properties of the film, especially its temperature characteristics.

It has been found that hand, 1 strength, elongation characteristics and moisture permeability are greatly affected. First, the copolymerization composition ratio of amino acid and urethane is 1.As is clear from Figure 1, which shows the infrared absorption spectrum of a typical PAD resin, 3290 cm-' (A), which is attributed to the stretching vibration of the Ni group, and the film. 2950c attributed to CH asymmetric stretching vibration used in thickness correction band
This is possible by determining the absorbance ratio of m-' (B). Therefore, various PAD resins having a composition ratio (weight fraction) of amino acids and urethane of 10 to 90:90 to 10 were synthesized and their infrared absorption spectra were taken.

The ratio of absorbance at 3290 cm and 2950 cm was determined.

Next, when we evaluated the texture of the moisture-permeable waterproof fabric coated with these PAII resins in the temperature range of -30℃ to +20℃, we found a correlation between the above absorbance ratio and cold resistance properties. . That is, if the absorbance ratio is less than 0.4, the cold resistance properties will be poor and hand hardening will become noticeable. On the other hand, when the ratio of 1 to 1 absorbance exceeds 2°O, the amino acid ratio increases, and the film has excellent cold resistance and moisture permeability, but the film has low elongation and poor elastic recovery, resulting in a hard texture and The adhesion also deteriorates. Therefore, it is necessary to use a PAU resin having an absorbance ratio in the range of 0.4 to 2.0 in terms of cold resistance and film properties. Next, the same tendency as the cold resistance property was observed for heat resistance, and the above absorbance ratio was 0.
For PAU resins in the range of 4 to 2.0.

Unlike polyurethane elastomers, the thermal adhesion temperature may rise or the porous membrane may be deformed during the normal heat treatment process.
It does not cause a decrease in moisture permeability. Further, in the case of conventional polyurethane elastomers, transfer printing has been impossible due to problems of heat curing and decreased moisture permeability, but transfer printing is also possible with the moisture permeable waterproof fabric of the present invention.

The reason why PAD resin exhibits good thermal behavior even at low and high temperatures is thought to be due to the α-helical structure of poly-α-amino acids. In other words, α−
This is presumed to be because α-amino acids form intramolecular hydrogen bonds in the helical structure, making the rod-shaped molecule thermally stable.

The PAD resin used in the present invention is a copolymer consisting of amino acids and polyurethane, and the amino acids include DL-alanine, L-aspartic acid, L-cystine, L-glutamic acid, glycine, L-lysine, L-methionine, L
-leucine and its derivatives, and when synthesizing polyamino acids, amino acid N-carboxylic anhydride (hereinafter N-carboxylic anhydride is referred to as NCA) obtained from amino acid and phosgene is generally used. In the polyurethane, aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates are used singly or in mixtures thereof as isocyanate components.

For example, tolylene 2,4-diisocyanate 4,4゛-
Examples include diphenylmethane diisocyanate, 1,6-hexane diisocyanate, and 4-cyclohexane diisocyanate. Also.

The polyol component is polyether polyol.

Polyester polyols are used. Polyether polyols include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc., and polyester polyols include reaction products of diols such as ethylene glycol and propylene glycol with dibasic acids such as adipic acid and sepatic acid; Examples include ring-opening polymers such as caprolactone. The amines used in the copolymerization of amino acids and polyurethane include ethylenediamine, diethylamine, triethylamine, ethanolamine, and the like.

As described above, PAU resins are obtained by adding amines to the reaction system of various amino acids NCA and urethane prepolymers having isocyanate groups at the terminals. The PAU
As the amino acid component constituting the resin, optically active γ-alkyl glutamate-NCA is preferably used from the viewpoint of film performance, and among the optically active γ-alkyl glutamates, T-methyl is preferred from the viewpoint of price and film properties. -L-glutamate-NCA or T-methyl-D-glutamate is often advantageously selected as the amino acid component of the PA[I resin. In order to obtain the porous membrane of the present invention, it is advantageous to use a uniform resin composition made of a water-soluble solvent system from the viewpoint of both coating properties and wet film forming properties. As such a resin composition, among PAD resins, optically active T-
A reaction product of alkyl-glutamate-NCA and a urethane prepolymer is preferably used, but this is because the above-mentioned reactant is a solvent mainly containing a polar organic abrasion, such as a mixed solvent system of dimethylformamide and dioxane, and the amino acid and the urethane prepolymer. Weight ratio of 90:10 to 10
: This is because the above weight ratio can be freely selected while taking into consideration the required film properties in order to obtain a uniform resin solution over a wide range of 9Q.

In this way, by wet coating processing of PAD resin,
The reasons why high water pressure resistance and high moisture permeability can be obtained are not obvious. 2 When observing the cross section of the film of the obtained moisture permeable waterproof fabric, it is compared to polyurethane film.

In the case of a PAU resin film, the microcells are small, numerous in number, and uniformly distributed, which is thought to be a factor in providing high moisture permeability and high water pressure resistance. Furthermore, the high affinity of PAD resin itself for water vapor may be one of the driving forces for providing high moisture permeability.

Considering the molecular structure of the PAD resin used in the present invention, PAU resin is composed of a block copolymer of amino acids and urethane, and as mentioned above, the amino acid component forms an α-helical structure. , while the urethane component forms a random coil structure. This is because (1) the attribution of the amide band in the infrared absorption spectrum (amide V 615 cm-
'; key band of poly-γ-alkyl-monoglutamate α-helical conformation). In general, in the case of amino acid resins, the driving force behind their high moisture permeability is their high diffusion coefficient.
The reason for this is thought to be due to the α-helical structure of the amino acid resin, which has a large side chain. Taken together, it is highly conceivable that PAD resin has two structures, an α-helix structure and a random coil structure, and has a more relaxed backing structure at the interface between the two structures. It is thought that the loose backing state of the molecular structure and the hydrogen bonds between amide bonds give the polymer its own high water vapor permeability, unlike that of polyurethane elastomers.

In the present invention, a moisture-permeable waterproof fabric with good cold resistance properties is obtained by applying the above-mentioned PAυ resin to a fabric. Combined use of compounds. In the present invention, an isocyanate compound is also used. 2,4- as an isocyanate compound
Tolylene diisocyanate, diphenylmethane diisocyanate.

Isophorone diisocyanate, hexamethylene isocyanate, or triisocyanates obtained by an addition reaction between 3 moles of these diisocyanates and 1 mole of a compound containing active hydrogen (eg, trimethylolpropane, glycerin, etc.) are used. The above-mentioned isocyanates may be in the form of free isocyanate groups, or may be stabilized by adding phenol, methyl ethyl ketoxime, etc., and the blocks may be dissociated by subsequent heat treatment. However, it can be used as appropriate depending on the workability and purpose. The amount of isocyanate compound used is PA
0.1-10% based on D resin.

It is desirable to use it preferably in a proportion of 0.5 to 5%. If the amount used is less than 0.1%, the adhesive strength of the resin to the fabric will be poor, and if it exceeds 10%, the texture will be hardened, which is not preferable.

Next, in the PAU resin film, a micropore-forming agent is used in combination to reduce the size of the microcells and to uniformly increase the number of pores on the surface.

The micropore-forming agents used here include anionic surfactants, nonionic surfactants, and! ! Examples include water-based polymers and polyurethane elastomers. The amount used is 0.5 to 10 in the case of anionic surfactants and nonionic surfactants based on the solid content of the PAU resin used together.
%, preferably in the range of 0.3 to 20% for hydrophilic polymers, and 1.5 to 30% for polyurethane elastomers. If the amount of these micropore-forming agents used is less than the above range, the pores of the PAU resin film will become too small.

It becomes difficult to obtain connected microcells, resulting in poor moisture permeability. Moreover, when the amount exceeds the above range, the pores become too large and high water pressure resistance cannot be obtained.

The anionic surfactants used as the above-mentioned micropore-forming agent include conventionally known alkyl sulfate ester salts, alkylbenzene sulfonates, α-olefin sulfonates, alkyl sulfonates, fatty acid amide sulfonates, and dialkyl sulfosuccinic acids. Salt, etc. or any mixture thereof.

In addition, nonionic surfactants include polyoxyethylene alkyl ether, polyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene fatty acid amide ether, polyhydric alcohol fatty acid ester, polyoxyethylene polyhydric alcohol fatty acid ester, fatty acid It refers to a 5I sugar ester, an alkylo-doamide, etc., or any mixture thereof.

Hydrophilic polymers include holivinylpyrrolidone, polyacrylic acid, polyacrylic ester, carboxyvinyl polymer organic amine, and polyethyleneimine, and are substances that can be dissolved or emulsified in polar organic solvents and are soluble in water. It is a polymer that can be used.

A polyurethane elastomer is a polymer obtained by reacting a polyisocyanate and a polyol, and known aliphatic and aromatic polyisocyanates can be used as the polyisocyanate.

Examples include hexamethylene diisocyanate, toluene diisocyanate, xylene diisocyanate, and reaction products of excess thereof with polyhydric alcohols. As the polyol, known polyethers, polyesters, and other polyols used in the production of ordinary polyurethane resins can be used. Examples of polyesters include ethylene glycol, diethylene glycol or 1,4-
Polyhydric alcohols such as butanediol and adipic acid.

Examples include reactants of polybasic carboxylic acids such as oxalic acid or sebacic acid. Examples of polyether include polyhydric alcohols such as ethylene glycol and propylene glycol to which one or more alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide are added.

In the present invention, the above-mentioned PAD resin, isocyanate compound, micropore forming agent, and polar organic solvent are used in combination, and the polar organic solvents used here include dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and hexamethylene phosphorus. There are amides, etc. These substances are highly soluble in water, and when a polar organic solvent solution of a water-insoluble resin is immersed in water, only the polar organic solvent dissolves in the water, and the resin coagulates in the water. A resin coagulation method using such a method is generally called a wet coagulation method.

When a resin is coagulated by a wet coagulation method, a trace amount of the polar organic solvent present in the resin is eluted into water, so a resin having countless micropores can be obtained.

A resin solution consisting of a PAD resin, an isocyanate compound, a pore-forming agent, and a polar organic solvent may be applied to a fiber fabric by a conventional coating method. Generally, the coating thickness of the resin is 10 to 300 μm due to machine performance.

The fiber fabrics mentioned here include nylon 6 and nylon 6.
6, polyester synthetic fibers such as polyethylene terephthalate, polyacrylonitrile synthetic fibers, polyvinyl alcohol synthetic fibers, semi-synthetic fibers such as triacetate, nylon 6/cotton, polyethylene terephthalate/ Examples include woven and knitted fabrics, non-woven fabrics, etc. made of blended fibers such as cotton.

In the present invention, these fiber fabrics are processed using TA solution treatment. The water repellency of the fabric is JIS L-1
It is desirable that the water content is 18 and 90 or more using the 096 spray method. The water repellent used may be a known one such as a paraffin 1B water repellent, a polysiloxane water repellent, or a fluorine water repellent.
The treatment may be carried out by a generally known method. If particularly good water repellency is required, use fluorine thread I8 water agent.

For example, padding Asahi Guard 730 (a seven-silicon water repellent emulsion) manufactured by Asahi Glass Co., Ltd. with a 5% aqueous solution (
This may be carried out by a method of performing heat treatment at 160° C. for 1 minute after a reduction rate of 35%).

After applying the above-mentioned resin solution to the fiber fabric, the fabric is immersed in water, but the water temperature at this time is preferably in the range of 0 to 30°C. diffusion becomes faster and the micropores in the resin film become larger.

As a result, the water pressure resistance may become poor. Also.

The dipping time must be at least 10 seconds; if it is less than 10 seconds, the resin will not coagulate sufficiently and a satisfactory PAU resin film will not be obtained.

After coagulating the PAU resin in water, the fabric is washed with hot water to remove any remaining solvent. The hot water washing conditions vary depending on the amount of PAD resin and micropore forming agent used, but the temperature is 30 to 80°C.
It is sufficient to carry out the process at a temperature of 3 minutes or more. After washing with hot water, dry.

In the above method, a water-repellent treated fabric was used as the fiber fabric, but this fiber fabric must be treated with water-repellent treatment in advance (it is not necessary, and the fabric obtained after lamination may be treated with water-repellent treatment). .

Regarding the water repellent agent and water repellent treatment method used here, the padding method is used as appropriate in accordance with the method used when the fiber fabric is previously treated with water repellency as described above.

Water repellent treatment may be performed by a spray method, a coating method, or the like. Also, to increase the durability of tθ water.

Water repellent treatment can also be performed using a resin such as melamine resin.

In the method of the present invention, the ↑Ω water treatment may be performed both before and after coating, and in this case, a product with even better water pressure resistance can be obtained. Also,
In order to improve the smoothness and flexibility of the fabric, the fabric may be further coated with a polysiloxane resin. As a polysiloxane to be applied.

Dimethylpolysiloxane, phenyl group-containing polysiloxane, modified silicone oil such as amino-modified or olefin-modified silicone oil, methylhydrogen polysiloxane or a mixture of dimethylpolysiloxane and methylhydrogen polysiloxane, etc. can be used, and they may be selected as appropriate depending on the application. 1 In the present invention, the molecular weight of dimethylpolysiloxane is 5.000 to 3.
0,000 is preferably used. This polysiloxane treatment.

First of all, it can impart smoothness to the fabric and reduce wear and tear on the film due to friction between the fabrics.

This smoothing effect also has the advantage of making it easy to put on and take off without using a lining. Second, the silicone resin adheres between the fabric structures and reduces the friction between the threads that make up the fabric, resulting in a softer texture. This polysiloxane treatment may be applied in the form of an aqueous dispersion, emulsion, or the like.

1.1.1. For the purpose of preventing treatment spots from occurring. - It may be applied as a solution of a chlorinated hydrocarbon such as trichloroethane, trichlorethylene, perchlorethylene, etc., or a solvent solution of toluene, hexane, mineral turpentine, etc. The method of applying polysiloxane resin is the commonly used padding method,
This may be done by a coating method, a spray method, or the like. The amount of polysiloxane attached is 0.1% solids based on the weight of the fiber.
The above is desirable.

(Example) Next, the present invention will be further explained with reference to Examples.

Performance measurements and evaluations in this example were performed in the following manner.

(11 Water pressure resistance JIS L-1096 (low water pressure method) (
2) Water repellency JIS L-1096 (spray method) (
31, i! rW degree JIS Z-0208 (4) Infrared absorption spectrum A PAU resin consisting of a predetermined composition ratio of amino acids and urethane was diluted with dimethylformamide to an appropriate concentration and cast onto a glass plate.

Dry at 50-80°C to form a film with a thickness of 3-5μ. 2950cm attributed to asymmetric CH stretching vibration
-' absorbance is proportional to film thickness, so this 2950
A cm-' absorption hand is used as a thickness correction band. Regarding absorption strength.

The BC of a specific absorption band is determined by the baseline method shown in Figure 2 of the drawing.
AC is read and the absorbance ratio is determined by the following formula: CD-1o, -C In the present invention, the absorbance ratio = D3□. /Dzqs. seek.

(5) Cold resistance characteristics - Change in texture due to temperature - Changes in texture due to temperature are examined in an atmosphere of 30°C and +20°C, and evaluated using a 10-rank scale from QOI of flexibility to rigidity (1).

■Evaluation of waterproofness by rubbing during cold resistance - After the sample was left at 30°C for 2 hours and rubbed 100 times by hand, the water pressure resistance was measured and compared with the water pressure resistance at 20°C.

Example 1 First, PAU resin (polyamino acid urethane resin) used in this example was manufactured by the following method.

Polytetramethylene glycol (OH value 56.9) 9
85g and 222g of isophorone diisocyanate to 110g
The reaction was carried out at .degree. C. for 5 hours to obtain a urethane prepolymer (NCO equivalent: 1233) having isone anate groups at the terminals.

51 g of this urethane prepolymer and 119 g of γ-methyl-L-glutamate-NCA were mixed with 669 g of a mixed solvent of dimethylformamide/dioxane (weight ratio = 7/3).
102g of 2% hydrated hydrazine solution was added to this while stirring, and the reaction was carried out at 30°C for 3 hours, resulting in a viscosity of 23.
,0OOcps (25°C), an emulsion-like PAU resin solution with good fluidity was obtained. (PAU resin (1)) This PA
U resin (A) is used in formulation 1 described below. Next, the obtained PAU resin solution was cast onto a glass plate, and
A transparent film with a thickness of 5 μm was obtained by drying at °C. The infrared absorption spectrum of this film was measured, and the ratio of absorbance at wave numbers of 3290 cm-' and 2950 cm-' was found to be 1.90.

Here, a plain fabric (taffeta) with a warp density of 120 threads/inch and a weft thread density of 90 threads/inch, using nylon 70 denier/24 filaments for the warp and nylon 70 denier/34 filaments for the weft, was refined and dyed with acid dye. Prepare a material, pad it with 5% aqueous solution (squeezing ratio 35%) of Asahi Guard 710 (product of Asahi Glass Co., Ltd.) of fluorine thread IB water-split emulsion, and then pad it with 160
After heat treatment at ℃ for 1 minute, the temperature was 170℃ and the pressure was 30kg using a calendar processing machine with mirror-finish rolls.
Calendering was performed under conditions of 20 m/cm/cm and a speed of 20 m/min. Next, a resin solution shown in Formulation 1 below was applied at a coating amount of 60 g/m using a knife-over roll coater, then immersed in a 20°C water bath for 30 seconds to solidify the resin, and then heated to 50°C. It was washed in warm water for 10 minutes and dried. The coated fabric of the present invention using the obtained PAU resin (A) was designated as Fabric A.

Formulation I PAU resin (A) 100 parts Dimethylformamide 10 parts Next 2 In order to further clarify the effect of the present invention, PAU resin (B) described below was used instead of PAU resin (A) in the coating solution of Formulation I.
) to (D) were used, and the isocyanate compound, micropore forming agent, and dimethylformamide had the same composition, and fabric B-D was obtained in the same manner as in Formulation 1. Fabric B is a moisture permeable waterproof fabric according to the present invention, and Fabric C and Fabric are comparative examples thereof.

(Production of PAU resin (B)) 111 g of the urethane prepolymer (NCO equivalent: 1233) used in Example 1 and 59 g of γ-methyl-monoglutamate-NCA were mixed with dimethylformamide/dioxane (weight ratio = 7/3). Dissolved in 666g of solvent.

Add 51 g of a 2% hydrated hydrazine solution to this while stirring and react at 30°C for 2 hours, resulting in a viscosity of 32.000c.
An emulsion-like PAU resin solution with good fluidity of ps (25° C.) was obtained. (PAD Resin (B)) The ratio of the absorbance at wave numbers 3290 cm-' and 2950 cm-' according to the infrared absorption spectrum of this PAD resin (B) was found to be 0.61.

(Production of PAD resin (C)) 153 g of the urethane prepolymer used in Example 1 (1 ton 1233 of NCO) and 17 g of γ-methyl-L-glutamate-NCA were mixed in a mixed solvent of dimethylformamide/dioxane (weight ratio = 7/3). Dissolved in 666g.

13 g of a 2% hydrous hydrazine solution was added to the mixture while stirring, and the reaction was carried out at 30° C. for 5 hours to obtain a translucent PAU resin solution with good fluidity. (PAD resin (C)) The ratio of the absorbance at wave numbers 3290 cm-' and 2950 cm-' according to the infrared absorption spectrum of this PAD resin (C) is 0.2, which indicates that it is a flexible resin composition. In general, it was urethane-like and had evening and light properties.

(Production of PAD resin (D)) 25.5 g of the urethane prepolymer (NGO equivalent weight: 1233) used in Example 1 and 144.5 g of γ-methyl-glutamate-NCA were mixed with dimethylformamide/dioxane (weight ratio = 7/3) mixed solvent 666g
120g of 2% hydrated hydrazine solution was added to this while stirring, and the reaction was carried out at 30°C for 3 hours to form a yellow-brown emulsion resin solution with good fluidity and a viscosity of 18,000 cps (at 25°C). Obtained. (PAD resin (D)) Based on the infrared absorption spectrum of this PAU resin (B)
The ratio of the absorbance at a wave number of 3290 cm'' and 2950 cm'' was determined to be 2.3, indicating that the composition was rigid and brittle (and exhibited low elongation).

The performance of four moisture-permeable waterproof fabrics (fabrics A-D) made of PAtl resins (A) to (D) was measured and evaluated, and the results are shown in Table 1.

Table 1 As is clear from Table 1, both Fabric A and Fabric B according to the present invention exhibit excellent moisture permeability and water pressure resistance, and furthermore, their texture does not change even under extreme environmental changes with a temperature difference of 50°C. It was found that there was no change in water pressure resistance after bending, and that it could be used satisfactorily even in extremely cold conditions. On the other hand, in the case of Comparative Fabric C, it was a fabric with a urethane feel and was resistant to changes in water pressure and temperature after bending, and was only comparable to conventional urethane coated products. Also.

In the case of comparative fabrics, the texture of polyα-amino acids,
The physical properties are similar, and the initial performance of moisture permeability and water pressure resistance was good, but because the texture was stiff and the elongation was low, the film was damaged by bending, and the film surface after 100 times of manual rolling was When observed, the film was found to have peeled off from the base fabric surface.

Example 2 In order to further improve the water pressure resistance of the fabric, Example 1
The fabrics A and B obtained in 1 and the comparative fabrics C and D were subsequently subjected to the following ta water treatment process, respectively. PA [made of I resin (B)] and comparative moisture-permeable waterproof fabrics C'' (PAD resin (C) Niyorumo (7)) and D' (made of PAU resin (D)) were obtained.

[Water repellent treatment process]

Asahi Guard was padded with an aqueous solution consisting of 5% G-710 (fluorinated TA water emuldisin, product of Asahi Glass Co., Ltd.) and 10% isopropyl alcohol (squeezing ratio 35%), and after drying at 160°C for 1 minute. Perform heat treatment.

The performance of the obtained fabric was measured and evaluated, and the results are shown in Table 2.

As is clear from Table 2, both the moisture permeable waterproof fabrics A' and B'' according to the present invention have good moisture permeability and water pressure resistance, and the texture does not harden even at -30°C. No decrease in water pressure resistance was observed after bending.

On the other hand, in the case of comparative fabric C', the hand hardening at -30°C was large and the water pressure resistance after bending was large. Also, in the case of comparative fabric D.

Since the texture was stiff and the elongation was low, the film was damaged by bending, and when the film surface was observed after 100 hand-rubbings, it was found that the film had peeled off from the base fabric surface.

(Effects of the Invention) The present invention has a wave number of 3290c in an infrared absorbing svettle.
m-' and 2950 cm-' absorbance ratio is 0.4 to 2.
1 The fabric obtained according to the present invention has good cold resistance properties and has little texture hardening at low temperatures, so unlike conventional moisture-permeable waterproof fabrics, it can be used even in cold regions. A moisture-permeable waterproof fabric that can be used sufficiently can be obtained. The moisture-permeable waterproof fabric of the present invention is a material that is well suited not only for sports clothing but also for sahybar use in extremely cold regions.

[Brief explanation of drawings]

FIG. 1 shows an infrared absorption spectrum of PAU resin (polyamino acid urethane resin) used in the present invention, and FIG. 2 is a diagram showing the absorption intensity at a specific wave number (c+n-') determined by the baseline method. (A) - Wave number 3290cm-' NH telescopic vibration hand (B)- Wave number 2950cm-' Film thickness correction hunt CH asymmetrical telescopic vibration band XY -m-Baseline

Claims (4)

[Claims] (1) Wave number 3290 cm in infrared absorption spectrum
The ratio of absorbance between ^-^1 and 2950cm^-^1 is 0.4
A film made of a polyamino acid urethane resin in the range of ~2.0, which has microcells interconnected by pores in the thickness direction of the film, and micropores communicating with the microcells on the surface of the film. 1. A moisture-permeable waterproof fabric with excellent cold resistance, characterized in that it has a porous membrane having a myriad of properties bonded to one side of a water-repellent fiber fabric. (2) Wave number 3290 cm in infrared absorption spectrum
The ratio of absorbance between ^-^1 and 2950cm^-^1 is 0.4
A resin film in which a resin solution consisting of a polyamino acid urethane resin in the range of ~2.0, an isocyanate compound, a micropore forming agent, and a polar organic solvent is applied to one side of a fiber fabric, then immersed in water, washed with hot water, and dried. A method for producing a moisture-permeable waterproof fabric with excellent cold resistance, comprising a forming step and a water-repellent step of treating the fiber fabric to make it water-repellent. (3) The method for producing a moisture permeable waterproof fabric according to claim 2, wherein a water repellent step is performed after the resin film forming step. (4) The method for producing a moisture permeable waterproof fabric according to claim 2, wherein a resin film forming step is performed after the water repellent step.