JPH05309793A - Production of moisture permeable waterproof cloth - Google Patents

Abstract

PURPOSE:To enhance moisture permeable waterproofness by applying a resin solution prepared by adding specific inorg. salts to a specific sythetic polymer to a release film and immersing the coated film in a specific mixed aqueous solution to coagulate the resin layer on the film to form a resin film and subsequently laminating the film to cloth in a spot-bonded state. CONSTITUTION:In the production of moisture permeable waterproof cloth, at first, a resin solution propared by adding inorg. salts with a particle size of 20mum or less to a synthetic polymer based on a polyurethane resin in an amount of 1% or more is applied to a release film and the coated release film is immersed in a mixed aqueous solution having dimethylformamide and inorg. salts respectively dissolved therein in an amount of 1% or more to coagulate the resin layer to form a film. This film is laminated to cloth through an urethane adhesive in a spot-bonded state. By this method, laminated type moisture permeable waterproof cloth excellent in moisture permeability and waterproofness as various clothings such as a raincoat or an overcoat and having the flexible touch is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminate type moisture-permeable and waterproof cloth having a flexible texture, which is used for various kinds of clothes such as rain clothes and outer garments and has excellent moisture-permeable and waterproof properties. Is.

[0002]

2. Description of the Related Art Conventionally, it has been known that a coated cloth obtained by a wet or dry coating method has a resin layer with a hole and a resin layer without a hole. Generally, when the resin layer is perforated, excellent moisture permeability is easily obtained, but waterproof performance tends to be insufficient. Conversely, when the resin layer is non-perforated, excellent waterproof performance is easily obtained, but moisture permeability is Performance tends to be insufficient. For example, although the coated fabric obtained by the wet coating process of polyurethane resin is originally excellent in waterproof performance, it has insufficient moisture permeability, so in order to improve moisture permeability, an anionic surfactant, nonionic It is usual to use a system surfactant, hydrophilic polymer, etc. together. However, the moisture permeability of the coated fabric obtained by this method is not sufficient, and the waterproof performance is considerably lowered, and as a result, both cannot satisfy sufficient performance.

In recent years, for the purpose of compensating for the defects of both, a highly moisture-permeable resin layer having pores is first formed on a fiber cloth, and a non-porous urethane resin layer is formed on the moisture-permeable film as a top coat layer, A method for obtaining excellent moisture permeability and waterproof performance has been attempted. In this method, a porous moisture permeable resin layer is used even when the wet method is used.
Since 00~6000g / m ² / 24hrs approximately breathable only obtained not, even when if thin coat of resin layer of non-porous to do next, moisture permeability is extremely decreased, resulting in excellent moisture At present, it is difficult to achieve both wet performance and waterproof performance. Further, in this case, coating is performed twice, which is disadvantageous in terms of processing cost.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and has high water pressure resistance and moisture permeability,
Moreover, it is an object of the present invention to produce a moisture-permeable waterproof fabric having a soft texture that does not cause discomfort when worn.

[0005]

The present invention achieves the above object and has the following constitution.

That is, the present invention provides that "a synthetic polymer mainly composed of a polyurethane resin is provided with an inorganic salt having a particle diameter of 20 μm or less.
% Of the resin solution is applied on the release film, and then the film is formed by immersing and coagulating in a mixed aqueous solution in which dimethylformamide and inorganic salts are dissolved in 1% or more, respectively, to form a film. The point is "a method for producing a moisture-permeable waterproof fabric having a soft texture, which is characterized by performing point-adhesive lamination on a fabric via an adhesive."
Hereinafter, the method of the present invention will be described in detail.

The polyurethane resin used in the present invention is a reaction product containing a polyol having hydroxyl groups at both ends, an organic diisocyanate and a chain extender. As the above-mentioned polyol component, polyether polyol,
Examples thereof include polyester polyols, mixtures or copolymers thereof, examples of polyether polyols include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like, and examples of polyester polyols include ethylene glycol, propylene glycol. , A polycondensation product of a diol such as hexamethylene glycol and a dibasic acid such as adipic acid, sebacic acid, maleic acid, and terephthalic acid, and a ring-opening polymer such as caprolactone and lactone acid.

As the organic diisocyanate component, aromatic diisocyanate, aliphatic diisocyanate and alicyclic diisocyanate may be used alone or in a mixture thereof. For example, tolylene-2,4-diisocyanate,
4,4'-diphenylmethane diisocyanate, 1,6-hexane diisocyanate, 1,4-cyclohexane diisocyanate and the like can be mentioned.

As the chain extender, ethylene glycol,
Examples thereof include compounds having active hydrogen such as diols such as propylene glycol and hexamethylene glycol, and diamines such as ethylenediamine, metaphenylenediamine and naphthylenediamine.

In the present invention, the resin solution of the above-mentioned polyurethane synthetic polymer is 20 μm or less, preferably 10 to 0.1 μm.
The powder of sodium chloride, calcium chloride, magnesium chloride, potassium chloride, etc. having a particle size of m is added alone or in a mixture of two or more kinds, at least 1% or more, preferably 5 to 20%, and the viscosity of the resin solution is 10,000-
Add dimethylformamide to 40,000 (cps) and stir well.

When forming the moisture-permeable film, the surface is smooth and
In addition, woven fabrics that have undergone processing to reduce the solubility parameter with fluororesins, silicone resins, polypropylene, etc.,
A polyurethane resin solution containing the above-mentioned salts is applied onto a release film such as a film or paper and solidified by a wet coagulation method to form a moisture permeable film. When applying, use a knife coater,
The coating is performed by using a known coating method such as a comma coater or a reverse coater, and the moisture permeable membrane to be obtained is appropriately adjusted to have a thickness of 5 to 50 μm.

The resin solution is preferably filtered and defoamed with a 50 to 200 mesh filter cloth in order to produce a uniform film without pinholes or foreign matter on the resin film.

In the present invention, during wet coagulation, dimethylformamide and sodium chloride, calcium chloride, magnesium chloride, potassium chloride alone or in a mixture of 1% or more, preferably 5 to 20% are dissolved in the coagulation bath.
Coagulate in a mixed aqueous solution at -20 ° C. According to this structure, the inorganic salts added to the resin solution at the same time as the resin coagulates are dissolved and disappear in the coagulation liquid, so that the sites where the inorganic salts were present in the resin become vacant and fine A porous structure is formed.

Upon solidification, the resin solution is applied onto the release film, immersed in a solidification solution for 5 to 10 minutes to solidify, and then washed with warm water at 50 ° C. for 15 minutes. Then, it is dried by a usual method. The moisture permeable membrane used in the present invention can be obtained by the above method.

In the present invention, the moisture permeable film on the release film thus obtained is laminated with a fiber cloth with an adhesive. Examples of the adhesive used in the present invention include polyurethane-based adhesives, polyamide-based adhesives, polyester-based adhesives, and the like, and the forms include solvent type, emulsion type, hot melt type and the like. These may be appropriately selected and used according to the type of cloth, etc., but a polyurethane solvent-based adhesive can obtain even better results in terms of adhesion after lamination.

As the fiber cloth used here, polyamide synthetic fibers represented by nylon 6 and nylon 66, polyester synthetic fibers represented by polyethylene terephthalate, polyvinyl alcohol synthetic fibers, polyacrylonitrile synthetic fibers, triacetate. Woven fabrics, knitted fabrics, non-woven fabrics, and the like, which are composed of semi-synthetic fibers such as Nylon 6 / cotton, mixed fibers such as nylon 6 / cotton, polyethylene terephthalate / cotton, and mixed fibers.

At the time of lamination, a dry film of 5 to 60 g / m ² is formed on the fiber cloth by using the above-mentioned adhesive solution using a coating machine such as a gravure coater or a spray coater.
The coating amount is appropriately set so that
Dry at 0 ℃ for 0.5-10 minutes, and then overlay a moisture permeable membrane on it, 50-150 ℃, 0.5-10kg / cm
Perform thermocompression bonding under the conditions of ² . If the conditions for thermocompression bonding are 150 ° C. or higher and 10 kg / cm ² or higher, the porosity of the film may collapse, which is not preferable.

At the time of applying the adhesive, the adhesive solution is applied in the form of dots, and the adhesive area is 40 to 60% of the cloth area.
Applying with a gravure coater, for example, under the condition that one spot area is 0.1 to 10 mm ² and the spot interval is 0.5 to 5 mm.
Further, it is possible to obtain a good moisture-permeable waterproof cloth having a high moisture permeability and a soft texture.

After laminating, the release film is peeled off to obtain the moisture-permeable waterproof fabric of the present invention. Further, if necessary, a water repellent treatment may be performed by a known method using a fluorine-based water repellent.

[0020]

[Operation] Apply a resin solution containing 1% or more of an inorganic salt having a particle size of 20 μm or less to a polyurethane resin on the release film,
When this is immersed in a mixed aqueous solution in which dimethylformamide and inorganic salts are dissolved at 1% or more and solidified to form a film, the inorganic salts in the resin solution dissolve and disappear in the coagulation liquid at the same time when the resin solidifies. Therefore, vacancies are formed in the part where the inorganic salts were present in the resin. Moreover, when dimethylformamide and 1% or more of each of the dimethylformamide and the inorganic salts are dissolved in the coagulating solution in the coagulation solution when the inorganic salts are dissolved, the dissolution rate of the dissolved inorganic salts from the resin solution is controlled slowly. Therefore, the pores formed in the film become a large number of very fine pores, and exhibit high moisture permeability and high water pressure resistance. A moisture-permeable waterproof cloth having a soft texture is obtained by spot-bonding such a film to the cloth via a urethane adhesive.

The fabric laminated with the moisture permeable membrane of the present invention is
It is a moisture-permeable waterproof fabric that has high water pressure resistance without the need for top-coating as in the past and has excellent texture.

[0022]

EXAMPLES The present invention will be described in more detail with reference to examples. The measurement and evaluation of the performance of the cloth in the examples were carried out by the following methods. (1) Water pressure resistance According to JIS-L-1092 (high water pressure method). (2) Water vapor transmission rate According to JIS-L-1099 (A-1 method). (3) Feeling The following four-level evaluation was performed relatively by handling. ◎: Very soft ○: Soft △: Slightly hard ×: Hard

Example 1 First, a release paper laminated with a silicone resin film was prepared, and a resin solution shown in the following prescription 1 was applied to the release paper using a knife over roll coater to form a moisture-permeable film having a moisture permeability of 3 after drying.
After appropriately adjusting the coating amount to 0 μm,
Dimethylformamide and calcium chloride 10 each
% Solidified by dissolving in a 15% dissolved aqueous solution at 15 ° C for 5 minutes, followed by washing in warm water at 50 ° C for 15 minutes, followed by drying at a temperature of 50 ° C, and transparentizing on release paper. A wet film was formed. [Formulation 1] 1740-29B 100 parts (Urethane synthetic resin, product of Seiko Kasei Co., Ltd.) Calcium chloride 20 parts (average particle size 1 μm) Resamine X 2 parts (isocyanate cross-linking agent, product of Dainichiseika Kogyo Co., Ltd.) Dimethyl Formamide 30 parts

On the other hand, nylon fiber 70d for both warp and weft
Prepare a plain woven fabric (taffeta) with a warp density of 120 / inch and a weft density of 80 / inch using / 136f, and after scouring, drying and presetting it in the usual way, in a circular dyeing machine, Mitsui Nylon Blue BL (product of Mitsui Toatsu Co., Ltd., acid dye) was dyed in a navy blue color with 3.0% owf. Next, after impregnating a 5% aqueous solution of Asahi Guard 710 (product of Asahi Glass Co., Ltd.) of a fluorine-based water repellent emulsion and squeezing with a pickup 100%, 15
Heat treatment was performed at 0 ° C. for 2 minutes, and then calendering was performed at 170 ° C. under the conditions of 300 kg / cm using a calendering machine having a mirror surface roll to obtain an ultrafine fiber fabric used in the present invention.

On the calendered surface of this fiber cloth, a polyurethane adhesive solution shown in the following Formulation 2 was applied using a gravure coater with a dot area of about 1 mm ² , a dot interval of about 2 mm, and an application amount of 12 g / m ² . , Then, after performing pre-drying at 110 ° C. for 30 seconds, the above-mentioned moisture permeable membranes are overlapped, and 8
Thermocompression bonding was performed under the conditions of 0 ° C. and 2 kg / cm ² and laminated. [Prescription 2] Heimren Y-119 (E) 100 parts (urethane adhesive, product of Dainichiseika Kogyo Co., Ltd.) Resamine NE 8 parts (crosslinking agent, product of Dainichiseika Kogyo Co., Ltd.) Resamine HI-215 2 parts ( Crosslinking accelerator, product of Dainichiseika Kogyo Co., Ltd.) Toluene 15 parts Methyl ethyl ketone 15 parts

48 hours after laminating the moisture permeable film, the release paper is peeled off, and the surface of the moisture permeable film is subjected to gravure coating with a 5% aqueous solution of Asahi Guard 710 by a gravure coater, and after drying, Heat treatment was performed at 150 ° C. for 1 minute to obtain a coated fabric of the present invention.

For comparison with the present invention, a moisture-permeable waterproof cloth for comparison (comparative example) was prepared in the same manner as in this example except that calcium chloride was removed from the treatment liquid of formulation 1 in this example. 1) was obtained. For comparison with the present invention, the same method as in this example was used for comparison except that the surface was adhered by applying a coating amount of 20 g / m ² using a knife over roll coater for adhesion. A moisture-permeable waterproof fabric (referred to as Comparative Example 2) was obtained.

The performance of the moisture-permeable waterproof fabrics of the present invention and Comparative Examples 1 and 2 was measured and evaluated, and the results are also shown in Table 1.

[Table 1]

As is clear from Table 1, the moisture-permeable waterproof fabric according to the method of the present invention has excellent moisture permeability without losing high water pressure resistance and has a very soft texture. It was

[0030]

According to the method of the present invention, it is possible to produce a laminate-type moisture-permeable waterproof cloth having an excellent moisture permeability and a very soft texture without losing high water pressure resistance. it can. Because of these properties, it is a material suitable for sports clothing in harsh environments, fishing, outdoor rainwear, and outerwear.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location D06M 15/564 // C08J 9/26 101 7148-4F D06M 23/16 C08L 75:04 8620-4J

Claims (1)

[Claims] 1. A synthetic polymer mainly composed of polyurethane resin,
A resin solution containing 1% or more of an inorganic salt having a particle size of 20 μm or less is coated on a release film, and then immersed in a mixed aqueous solution in which 1% or more of each of dimethylformamide and an inorganic salt is dissolved and solidified to form a film. And a film is laminated on a cloth by means of a urethane adhesive to form a point adhesive laminate on the cloth, and a method for producing a moisture-permeable waterproof cloth having a soft texture.