JPH0735637B2 - Breathable waterproof fabric - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a novel breathable waterproof fabric, and more particularly to a novel lightweight breathable waterproof fabric having a continuous resin thin film and having a good texture, and a method for producing the same. .

<Prior Art> Conventionally, as a moisture-permeable waterproof cloth having a continuous resin thin film and having a good texture, those in which a microporous thin film is laminated on the cloth and those which are repeatedly coated with a gravure coater are known. . However, since the former requires an adhesive layer, it has a drawback that the moisture permeability of the microporous thin film cannot be sufficiently exhibited. In the latter case, coating is required to be repeated several times to form a continuous resin thin film, which is problematic in productivity.

<Problems to be Solved by the Invention> An object of the present invention is to provide a moisture-permeable waterproof fabric that does not have the above-mentioned drawbacks, and particularly, to have a continuous resin thin film having excellent moisture permeability and also excellent productivity. It is to provide a lightweight, breathable waterproof fabric having a good texture.

<Means for Solving the Problems> The moisture-permeable waterproof cloth of the present invention is obtained by impregnating the cloth with a solution prepared by dissolving one monomer having polycondensation or polyaddition reactivity in the solvent A, and then by adding the solvent A to the solution. Is a non-compatible solvent B having a specific gravity smaller than the specific gravity of the solvent A, and the other monomer having polycondensation or polyaddition reactivity is dissolved in the solution B to bring the cloth into contact with the solution to form an interface on the cloth. The fabric is characterized by having a continuous resin thin film having a film thickness of 10 μm or less and having a serpentine fold-like surface structure having a height of 10 μm or less at intervals of 25 μm or less, which is formed by polymerization.

Examples of the combination of the monomers having polycondensation reactivity in the present invention include a system for producing a polyamide and a system for producing a polyester. Aliphatic or aromatic dibasic acid dihalides are used as the acid component monomer of the system for producing polyamide and polyester. For example, dihalides of aliphatic dibasic acids such as adipic acid and sebacic acid, terephthalic acid, isophthalic acid, dihalides of aromatic dibasic acids such as 4,4′-diphenylmethanecarboxylic acid, cyclohexanedicarboxylic acid, dicyclohexyl. Examples include dihalides of alicyclic dibasic acids such as methanedicarboxylic acid, polyamides having at least one carboxylic acid halide residue, polyester prepolymers, and the like.
Aliphatic or aromatic diamines and diols are used as the corresponding monomers to be polycondensed with these acid component monomers. For example, as diamines, aliphatic diamines such as ethylenediamine, trimethylenediamine, and hexamethylenediamine, aromatic diamines such as o-, m-, p-phenylenediamine, and alicyclic compounds such as cyclohexanediamine and cyclohexylmethylenediamine. Formula diamines, polyamides having at least one or more amine residues, prepolymers of polyurethane, and the like, and examples of diols include aliphatic diols such as ethylene glycol, tetraethylene glycol, and polyethylene glycol, hydroquinone, and resorcin. , Bisphenol A, aromatic diols such as diphenylmethanediol, alicyclic diols such as cyclohexanediol and dicyclohexylmethanediol, polyester having at least one or more hydroxyl residues Examples include a prepolymer of letane. Further, by trapping the acid generated by the condensation reaction with alkali such as NaOH, the polymerization reactivity is improved.

Examples of the combination of the monomers having polyaddition reactivity in the present invention include a system for producing polyurethane. The above diamines and diols can be used as they are as one of the component monomers in the system for producing polyurethane. An aliphatic or aromatic diisocyanate is preferably used as the other component monomer. For example, hexamethylene diisocyanate, aliphatic diisocyanates such as trimethylolpropane diisocyanate, toluene diisocyanate, aromatic diisocyanates such as diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, alicyclic diisocyanates such as isofluorone diisocyanate, isocyanate residue Examples include polyurethane prepolymers having at least one or more.

When two or more kinds of mixed monomers are used, a polymer film having a copolymerization ratio corresponding to the mixing ratio can be obtained. Further, since the monomers can be freely selected, it is possible to obtain a resin film which cannot be formed into a film by ordinary heating film formation. Particularly, in the system of a dihalide of an aromatic dibasic acid such as terephthalic acid dihalide or isophthalic acid dihalide and an aromatic diamine such as phenylenediamine, an aromatic polyamide coating having good heat resistance can be obtained.

The cloth referred to in the present invention means synthetic fibers such as polyamide, polyester and polyacrylic and modified fibers thereof, natural fibers such as wool, silk, cotton and hemp, semi-synthetic fibers such as acetate and rayon, or the like. A sheet-like material made of mixed fibers, for example, a woven or knitted fabric, a non-woven fabric, or the like.

The fabric preferably has an air permeability of 20 cc / cm ² · sec or less. In the case of a fabric having an air permeability of more than 20 cc / cm ² · sec, the resin film that is generally formed is not completely covered, and sufficient water resistance cannot be obtained.

The method of polymerizing the monomers on the cloth is performed by an interfacial polymerization method in which the cloth is impregnated with one of the monomer solutions and then the cloth is brought into contact with a solution in which the other monomer is dissolved in a solvent that is incompatible with the solvent. .

It is important that the solvent of the solution containing the monomers that is not compatible with each other has a smaller specific gravity of the solvent of the solution contacting the cloth impregnated with one of the monomer solutions than the specific gravity of the solvent of the solution impregnating the cloth. Is. Specifically, a combination of water or a lower alcohol such as methanol or ethanol and an organic solvent that does not dissolve in it is preferable, and the cloth is impregnated with a monomer solution using a solvent having a higher specific gravity to obtain a solution having a lower specific gravity. Contact the monomer solution with the solvent. In particular, a combination of water and hydrocarbons or halogenated hydrocarbons is preferable because the solubilities of the monomers in both solvents greatly differ. Which solvent solution is impregnated into the fabric first is determined by the degree of hydrophilicity of the fabric. That is, when the cloth has a high hydrophilicity, a solvent solution of water or lower alcohols is preferable, and conversely, when the cloth has a high lipophilicity, an organic solvent solution is preferable.

The monomer concentration is preferably about 0.1M to 2M. If it is less than 0.1M, the coating with the generated resin will be insufficient and the water resistance will be low, and if it is more than 2M, the amount of the generated resin attached will be too large and the weight will not be reduced and the texture will be hard. It is particularly preferably 0.3 to 1M. Further, it is preferable that the concentrations of both solutions are equal.

The thickness of the continuous resin thin film needs to be 10 μm or less. When the film thickness is larger than 10 μ, sufficient moisture permeability cannot be obtained, and the texture becomes hard and weight reduction cannot be achieved. In particular, the film thickness is preferably 3 μm or less in order to satisfy high levels of moisture permeability, texture and weight reduction.

The film structure of continuous resin thin film has a height of 25μ or less on the surface.
It is important in terms of moisture permeability to have a meandering pleated structure of 10 μm or less. In the present invention, the film thickness means the sum of the film thickness of the thin film portion having a uniform film thickness and the height of the pleated structure, and this sum also needs to be 10 μm or less. As a matter of course, the height of the pleated structure needs to be 10 μ or less. In addition, it is necessary that the interval of the pleated structure is 25 μ or less. If this interval is larger than 25 μ, there is almost no effect on the improvement of the film strength, and no effect of improving the durability is observed.
In this structure, since the durability can be improved by the pleated structure, the thin film portion can be further thinned, and since the surface area is increased, the moisture permeability can be improved. Furthermore, since the pleated structure is meandering, the reinforcing effect of the membrane is exerted more effectively.

<Function> The cloth having the continuous resin thin film of the present invention has both high moisture permeability and waterproof cloth property, has no adhesive layer and is excellent in durability, and is a one-step manufacturing method. Since the polymerization and coating are performed at low cost.

<Example> The present invention will be described in more detail with reference to the following examples.

The air permeability in the examples is measured by JIS L1096-1979A method using a Frazier type tester, and the water vapor permeability is JI.
It is measured by the SZ-0208 method using a moisture permeable cup. The water resistance is measured by JIS L1092-1977A method (low pressure method). The film thickness was obtained from an electron micrograph.

<Example 1> Nylon 6 taffeta (70 denier warp, 12 filament,
Weft 70 denier, 24 filament, weave density vertical 120 pieces / i
n, width 90 pieces / in, ventilation rate 14.32cc / cm ² · second, moisture permeability 9600g
/ m ² · 24hr, water pressure resistance 0mmH ₂ O), isophthalic acid dichloride 1M chloroform solution (specific gravity of chloroform: 1.489g /
cm ³ ), and then float on the surface of an aqueous solution of hexamethylenediamine 1 M and sodium hydroxide 2 M (specific gravity of water: 1.0 g / cm ³ ) for 2 minutes, then wash with water and dry, nylon with a thickness of 1μ A 6I coating film was formed. The performance of this fabric was as shown in Table 1.

<Comparative Example 1> The same treatment as in Example 1 was performed except that the concentration of isophthalic acid dichloride was changed to 2 M, to form a nylon 6I coating thin film having a thickness of 11 µm.

Example 2 A solvent for isophthalic acid dichloride was carbon tetrachloride (specific gravity: 1.5).
The same treatment as in Example 1 was carried out except that the coating film was changed to 95 g / cm ³ ) to form a thin film having a film thickness of 1 μ and a coating film having a pleated structure having a height of 9 μ and an interval of 15 μ.

<Example 3> The same treatment as in Example 1 was performed except that the concentration of isophthalic acid dichloride was changed to 0.5M, and a thin film having a film thickness of 2μ and a height of 5μ,
A coating film having a pleated structure with an interval of 5 μ was formed.

Comparative Example 2 The same treatment as in Example 1 was performed except that the concentrations of isophthalic acid dichloride, hexamethylenediamine, and sodium hydroxide were changed to 0.5M, 0.5M, and 1M, and a thin film with a thickness of 1 μm and a height of 5 were used.
A coating film having a pleated structure with a gap of 30 μ was formed.

<Effect of the invention> a. Light weight and soft texture.

b. Highly windproof and waterproof.

c. High moisture permeability.

d. Low cost because polymerization and coating are performed simultaneously.

e. A coating film that retains the appearance of the fabric.

f. There are various types of coating resins.

[Brief description of drawings]

All the drawings are electron micrographs showing the relationship between the shape of the fibers and the thin film of the moisture-permeable waterproof fabric of the present invention. Figures 1 and 2 show a film thickness of 1μ on nylon taffeta, respectively.
2 is an electron microscopic enlarged photograph of the surface and cross section of the thin film of Example 1 (Example 1), and FIG. 1 shows the surface portion of the thin film of 150 times, and FIG. 2 shows the nylon taffeta of 1000 times. It is a cross section of a thin film including a cross section. FIG. 3 and FIG. 4 are enlarged photographs of the surface and cross section of the one having a meandering pleated structure on the surface (Example 2), and FIG. 3 is a surface portion of a thin film of 150 times. Figure 4 shows the cross section of a thin film including the cross section of 1000 times nylon taffeta.

Claims (1)

[Claims] 1. After impregnating a cloth with a solution prepared by dissolving one monomer having polycondensation or polyaddition reactivity in a solvent A, the cloth has no compatibility with the solvent A and a specific gravity of the solvent A. Formed by bringing the cloth into contact with a solution obtained by dissolving the other monomer having polycondensation or polyaddition reactivity in the solvent B having a smaller specific gravity to cause interfacial polymerization on the cloth, at intervals of 25 μm or less. A moisture-permeable waterproof fabric, comprising a continuous resin thin film having a thickness of 10 μm or less and having a meandering pleated surface structure having a height of 10 μm or less on the fabric.