JPH07229070A - Production of coated fabric having moisture transmission and waterproofness - Google Patents

Abstract

PURPOSE:To provide a method for producing moisture permeable and waterproof coated fabric having excellent moisture transmission and waterproofing performances and a soft touch feeling. CONSTITUTION:This method for producing coated fabric having moisture transmission and waterproofness comprises a first process for coating fiber cloth with a solution of a synthetic polymer consisting essentially of a polyurethane resin by a wet coating method or a dry coating method to form a film and a second process for coating the formed film of the resin with a solution of a synthetic polymer consisting essentially of a polyurethane resin containing >=1wt.% of inorganic fine powder having <=1mum average particle diameter and >=200milli/100g adsorption amount of N,N-dimethylformamide by a wet coating method to form a film.

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 moisture-permeable and water-proof coated cloth having excellent softness and waterproofness and moisture permeability.

[0002]

2. Description of the Related Art Conventionally, a lamination method and a coating method are well known as methods for producing a moisture-permeable and waterproof cloth. The laminating method is a method that is obtained by bonding a moisture-permeable and waterproof resin film and a fiber cloth door with an adhesive. By reducing the amount of adhesive and the adhesive area at this joint, a soft feeling is obtained. Has obtained a moisture-permeable and waterproof fabric. However, the moisture permeable and waterproof fabric by the laminating method is easy to obtain excellent waterproof performance, but even if the amount of adhesive and the adhesive area are controlled as small as possible, the adhesive has almost no moisture permeable property, so it is sufficient. The actual situation is that the moisture permeability is not obtained.

On the other hand, the coating method includes a wet coating method and a dry coating method, and as the resin film formed by the coating method, a perforated film and a non-perforated resin film are known. 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 Is likely to be insufficient. For example, although the coating cloth obtained by the wet coating method of polyurethane resin is originally excellent in waterproof performance,
Since the moisture permeability is insufficient, it is usual to use anionic surfactants, nonionic surfactants, hydrophilic polymers, etc. together to improve the moisture permeability. However, although the moisture permeability of the coating fabric obtained by such a method is relatively good, it is not sufficient, and the waterproof performance is considerably deteriorated, and as a result, both are able to satisfy the sufficient performance. Absent.

Therefore, the inventors of the present invention previously disclosed in Japanese Patent Laid-Open No. 5-2
No. 22677, an inorganic fine powder having a porous resin layer made of a synthetic polymer mainly composed of polyurethane resin on a fiber cloth, the resin layer being substantially non-porous and having an average particle size of 0.1 μm or less. We have proposed a moisture-permeable waterproof coated fabric with high water pressure resistance and high moisture-permeation performance, which contains 1% or more of water. According to this method, it is possible to obtain a moisture-permeable and waterproof coating fabric having both excellent moisture permeability and waterproof performance. However, since the coating layer contains inorganic fine powder, the texture of the coating fabric is inevitable. Had a defect that it became hard.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a moisture-permeable waterproof coating fabric having both excellent waterproof performance and moisture-permeable performance and having a soft texture. It is intended to be manufactured.

[0006]

SUMMARY OF THE INVENTION The present invention achieves the above object and has the following configuration. That is, according to the present invention, the first step of applying a synthetic resin solution containing a polyurethane resin as a main component containing a water-soluble substance onto a fiber cloth to form a wet film or a dry film, and the average particle size on the resin film is A wet coating is applied by applying a polyurethane polymer-based synthetic polymer solution containing 1% by weight or more of an inorganic fine powder having an adsorption amount of N, N-dimethylformamide of 1 μm or less and 200 ml / 100 g or more. The gist of the present invention is a method for producing a moisture-permeable waterproof coated fabric, which is characterized by comprising steps.

The present invention will be described in detail below.

The fiber cloth used in the present invention includes polyamide synthetic fibers represented by nylon 6 and nylon 66, polyester synthetic fibers represented by polyethylene terephthalate, polyacrylonitrile synthetic fibers,
Examples thereof include woven fabrics, knitted fabrics, non-woven fabrics and the like made of polyvinyl alcohol synthetic fibers, semi-synthetic fibers such as triacetate, or mixed fibers such as nylon 6 / cotton and polyethylene terephthalate / cotton.

In the present invention, the above fiber cloth may be treated with a water repellent agent. This is one means for preventing the penetration of the resin solution into the fabric. In this case, the water repellent may be a known one such as a paraffin water repellent, a polysiloxane water repellent, or a fluorine water repellent, and the treatment thereof is also a commonly used padding method, spray method, or the like. The known method may be used. When particularly good water repellency is required, a fluorine-based water repellent is used. For example, Asahi Guard 730 (Asahi Glass Co., Ltd., fluorine-based water repellent emulsion) is padded with a 5% aqueous dispersion ( Aperture ratio 3
5%), and then heat treatment at 160 ° C. for 1 minute.

In the present invention, as a first step, a synthetic polymer solution containing a water-soluble substance as a main component of a polyurethane resin is applied onto the above-mentioned fiber cloth to form a film by a wet coating method or a dry coating method.

The polyurethane resin used here is a copolymer obtained by reacting a polyisocyanate and a polyol, and aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, or a mixture thereof is used as an isocyanate component. , For example,
Tolylene 2,4-diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,6-hexanediisocyanate, 1,4-cyclohexanediisocyanate, etc. are used, and as the polyol component, polyether polyol or polyester polyol is used, and polyether is used. Polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc. are used as the polyol, and ethylene glycol, polyester glycol are used as the polyester polyol.
A reaction product of a diol such as propylene glycol and a dibasic acid such as adipic acid or sebacic acid, or a ring-opening polymer such as caprolactone is used.

The synthetic polymer mainly composed of polyurethane resin as used in the present invention means the above-mentioned polyurethane resin in an amount of 50 to 100%.
Synthetic polymer including, other synthetic polymers such as acrylonitrile, acrylamide, vinyl acetate,
Polymers composed of vinyl chloride, styrene, etc., polybutadiene, polyamino acids, etc. may be contained in an amount of less than 50%, and the form thereof may be a copolymer or a blend. As for these synthetic polymers, compounds modified with fluorine, silicon or the like can also be used in the present invention.

Examples of the solvent for the synthetic polymer mainly composed of polyurethane resin include methyl ethyl ketone, ethyl acetate, toluene, N, N-dimethylformamide, dioxane, isopropyl alcohol and water.
In the case of the dry coating method in which a resin film is formed by drying after coating, it is advantageous to use highly volatile methyl ethyl ketone, ethyl acetate, toluene, isopropyl alcohol, etc. as the main solvent, while it is possible to solidify in water. In the case of a wet coating method for forming a resin film, a polar organic solvent such as N, N-dimethylformamide may be used as the main solvent.

In the present invention, the water-soluble substance used in combination with the polyurethane resin-based synthetic polymer solution includes starch, dextrin, polysaccharides such as sodium alginate, cellulose butyrate, cellulose acetate butyrate, and other cellulose esters, methyl cellulose, ethyl cellulose, Cellulose ethers such as carboxymethyl cellulose and hydroxyethyl cellulose, amino sugars such as chitin and chitosan, gelatin,
Natural water-soluble polymer compounds such as albumin, globulin, and other water-soluble proteins, or their derivatives;
Examples thereof include synthetic water-soluble polymer compounds such as polyvinyl alcohol and polyacrylamide.

The amount of the water-soluble substance used is 1 to 30% by weight, preferably 3 to 20% by weight, based on the solution of the synthetic polymer mainly composed of polyurethane resin, and the amount used is 1% by weight.
If it is less than 30% by weight, the effect of moisture permeability and feeling is poor, and if it exceeds 30% by weight, the peeling resistance to the fiber cloth is insufficient and the resin solution properties are not suitable for coating.

In the present invention, when a solution of a synthetic polymer mainly composed of a polyurethane resin containing a water-soluble substance is coated to form a film by a wet coating method, after coating, 0.5 to 3 ° C. to 30 ° C. water is applied. Wet solidification by immersing for 10 minutes, followed by washing in warm water at 40-80 ° C for 5-15 minutes, at the same time elute and remove water-soluble substances in coating resin solution and dry. By doing so, a resin film is formed. Further, when a film is formed by a dry coating method, a resin film is formed in a state of containing a water-soluble substance by drying after coating, and this water-soluble substance is formed by the wet coating in the second step described later. It is eluted and removed by the washing process at the time of.

In the wet or dry coating process of the first step in the present invention, coating is performed mainly on the concave portions of the base fabric so that the dry resin film weight is 10 g / m ² or less, preferably 5 g / m ² or less. . For coating, a knife coater, comma coater, reverse coater or the like may be used as appropriate, but the knife coater is most suitable in view of the resin coating amount.

In the present invention, after the film formation by the wet coating or the dry coating in the above-mentioned first step, the average particle diameter is 1 μm or less and the adsorption amount of N, N-dimethylformamide is 200 ml / on the resin film. The second step of film formation is carried out by applying a synthetic polymer solution mainly composed of polyurethane resin containing 100 g or more of inorganic fine powder in an amount of 1% by weight or more and performing wet film formation.

As the synthetic polymer solution mainly composed of polyurethane resin, one having the same composition as that used in the above-mentioned first step can be used, and the main solvent is a polar organic solvent such as N, N-dimethylformamide. It is advisable to use a solvent.
In the present invention, the synthetic polymer solution mainly composed of polyurethane resin has an average particle size of 1 μm or less and an adsorption amount of N, N-dimethylformamide of 200 ml / 100.
An inorganic fine powder of g or more is used by being contained in an amount of 1% by weight or more based on the synthetic polymer.

As the inorganic fine powder, any inorganic substance having the above performance can be used. A known method may be used for pulverizing the inorganic material. In particular, fine powders of metal oxides obtained by a vapor phase oxidation method of a metal halide, a combustion hydrolysis method, an electric arc method or the like are preferable. Among them, as the inorganic fine powders produced by the above method, silicon dioxide fine powders are preferable. Is cheap and is produced in large quantities, so it is good to use it.

The fine powders obtained by these methods generally have a particle size of 0.05 μm or less and, at the same time, show a very large amount of N, N-dimethylformamide adsorbed, and are dispersed in a synthetic polymer resin solution. It is suitable as an inorganic fine powder to be added. Further, if the surface of the fine powder is modified to be hydrophobic, it is more preferable from the viewpoint of improving the water leakage resistance of the coating film.

The above-mentioned amount of N, N-dimethylformamide adsorbed means that 5 g of inorganic fine powder is placed on a glass plate and N, N
-Every time one drop of dimethylformamide is dropped, the work of kneading with a spatula made of stainless steel is repeated,
It means the amount of adsorption of the next drop of N-dimethylformamide immediately before it suddenly becomes soft. The measuring method is J
The measurement is carried out according to the oil absorption measurement method of ISK-5101, but N, N-dimethylformamide is used instead of oil for the linseed oil, and the adsorption amount of N, N-dimethylformamide per 100 g of inorganic fine powder ( Unit: milliliter).

The inorganic fine powder used in the present invention must have an average particle size of 1 μm or less and an N, N-dimethylformamide adsorption amount of 200 ml / 100 g or more. The diameter is 0.1 μm or less, and the adsorption amount of N, N-dimethylformamide is 3
The amount of 100 ml / 100 g or more is more preferable in terms of the effect of the present invention. When the average particle size exceeds 1 μm, the pore size of the fine pores of the obtained coating film becomes too large, which lowers the waterproof performance, which is not preferable, and the adsorption amount of N, N-dimethylformamide is 2
When it is less than 100 ml / 100 g, the number of fine pores in the coating film is small and the moisture permeability is not so improved, which is not preferable.

The amount of the inorganic fine powder used in the present invention is required to be substantially uniformly 1% by weight or more based on the resin layer composed of the synthetic polymer mainly composed of the polyurethane resin, and more preferably. It is better to contain 3% by weight or more. If it is less than 1% by weight, the number of fine pores of the obtained coating film is too small, and the moisture permeability is not improved so much.

The inorganic fine powder does not necessarily have to be highly pure, and may contain other inorganic substances such as pigments and fillers as impurities.

In the second step of coating, a knife coater, comma coater, reverse coater or the like is appropriately used, coating is performed by adjusting the coating amount so that the dry resin film is 10 to 50 g / m ^2. 0-30
Wet solidification of the resin component is carried out by immersing in 0.5 ° C. water for 0.5 to 10 minutes. Thereafter, after washing in warm water of 40 to 80 ° C. for 5 to 15 minutes, it is dried by a usual method to form a resin film.

In the present invention, in the coating in the first step, the peeling resistance between the resin layer and the fiber cloth is improved, and in the coating in the second step, the peeling resistance between the resin layer and the resin layer is improved. For the purpose of improving the resin composition, a compound having a high affinity with the resin or the fiber cloth may be used together with the resin solution, and an isocyanate compound may be used together as the compound. As the isocyanate compound, 2,4-tolylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate or 3 mol of these diisocyanates and 1 mol of a compound containing active hydrogen (eg, trimethylolpropane, glycerin, etc.) The triisocyanates obtained by the addition reaction of can be used. The above isocyanates may be in a form in which the isocyanate group is free, or in a form in which the block is dissociated by the subsequent heat treatment after being stabilized by adding phenol, methylethylketoxime, or the like. However, it can be used, and it may be properly used depending on workability and purpose.

The amount of the isocyanate compound used is preferably 0.1 to 10% by weight based on the synthetic polymer mainly composed of the polyurethane resin.
If the amount used is less than 0.1%, the adhesive force of the resin layer to the fabric is low, and if it exceeds 10%, the texture tends to harden, which is not preferable.

In the present invention, for the purpose of further improving waterproofness, the coated fabric may be subjected to a water repellent treatment after the wet coating in the second step. For the water repellent treatment, the well-known water repellent treatment method that is generally carried out as described above may be adopted. In order to further improve the waterproof performance, a non-porous polyurethane resin layer having a dry film thickness of about 0.5 to 2 μm may be formed on the wet coating layer of the present invention. Since the wet coating layer has high water pressure resistance, the waterproof performance is synergistically improved even with a thin film, and the moisture permeability is not significantly reduced.

[0030]

[Operation] When wet or dry coating of a resin solution containing a water-soluble substance is performed in the first step as in the method of the present invention, the water-soluble substance is subjected to a cleaning treatment in the first step during wet coating, and , During dry coating, it is completely eluted and removed by the cleaning process in the second step, so it is possible to form a resin film with a large number of fine pores and high moisture permeability, and also a water-soluble substance. Is uniformly dispersed in the resin liquid, so that when the water-soluble substance is eluted and removed, the contact between the coating resin and the base cloth and the contact between the resin that has penetrated into the base cloth and the inside of the base cloth are As a result, the degree of freedom is increased and a coated fabric with a soft texture is obtained.

Then, in the second step, the average particle size is 1 μm.
When the wet coagulation is performed by coating a cloth with a synthetic polymer solution mainly composed of a polyurethane resin, in which an inorganic fine powder having an adsorption amount of N, N-dimethylformamide of 200 ml / 100 g or more is uniformly dispersed. , The coagulating liquid water and the resin solvent N, N-dimethylformamide are mixed, and the solvent is promptly released from the resin liquid to coagulate the resin. At that time, the average particle diameter is 1 μm or less, And the amount of N, N-dimethylformamide adsorbed is 2
When 100 ml / 100 g or more of the inorganic fine powder is uniformly dispersed in the resin solution, the surface of the inorganic fine powder has a higher concentration of N, N-dimethylformamide in the resin solution than the other parts, In other words, the concentration of the synthetic resin mainly composed of the polyurethane resin is low, so that in the wet coagulation process, the coagulating liquid, water, first replaces N, N-dimethylformamide on the surface of the inorganic fine powder, Solidification starts quickly around the inorganic fine powder, and then the entire resin solidifies, resulting in a faster solidification rate. In addition to the honeycomb structure peculiar to polyurethane resin,
It becomes a very porous form having innumerable fine pores of 1 μm or less. Due to the fineness of the formed fine pores, excellent waterproof performance is exhibited, and due to the innumerable fine pores, high moisture permeability is exhibited.

In the present invention, the moisture permeability is improved by the innumerable minute holes, so that the water leakage characteristic of a highly moisture-permeable waterproof fabric is likely to cause a problem when pressure is applied during wearing. Is also very effective against. Further, since the inorganic fine powder of the present invention is uniformly present in the entire resin layer on the wear side, the resin layer surface eliminates the slimy feeling peculiar to the polyurethane resin to give a dry touch, and the resin layer on the wear side. Overall wear resistance is improved.

[0033]

EXAMPLES The present invention will be described in more detail with reference to the following examples. The performance of the coated fabrics in the examples was measured by the following method. (1) Water pressure resistance: JIS L-1092 (high water pressure method) (2) Water vapor transmission rate: JIS L-1099 (A-1 method) (3) Water leakage: Bundesmann method (JIS L-109)
The amount of water leakage after 360 minutes was measured according to (Reference Test Method 2). (4) Abrasion strength: JIS L-1084 (A-1 method) (5) Feeling: Measured by handling, and the following three grades were relatively evaluated. ○ Soft △ Slightly hard × Hard

Example 1 Nylon high multifilament 7 for both warp and weft
Warp density 120 using 0 denier / 68 filament
Weaving a plain weave with a book / inch and weft density of 90 / inch, and scouring and dyeing by the usual method (manufactured by Mitsubishi Kasei Co., Ltd.,
After performing acid dye Diacid Light Green 2GS 1% owf), Asahi Guard 7 of fluorine type water repellent emulsion
10 (manufactured by Asahi Glass Co., Ltd.) was padded with a 5% aqueous dispersion (35% squeezing ratio), dried, and then heat-treated at 160 ° C. for 1 minute. Next, using a calendering machine with a mirror surface roll, temperature 170 ° C, pressure 35 kg / cm ² , speed 30
Calendering was performed under the condition of m / min to obtain a base fabric for coating.

Here, as the first step, the following prescription 1
22% solid content and viscosity 18000 cp /
The polyurethane resin solution at 25 ° C was applied to the calendar surface of the above base cloth at a coating amount of 25 g / m ² (dry resin film weight: 5.5 g / m ² ) using a knife coater, and immediately after that, it was placed in water at 15 ° C to 60 ° C. Immerse for 2 seconds to solidify the resin component, then 6
While washing for 10 minutes in warm water at 0 ° C, coagulation is completed, carboxymethyl cellulose (fine gum HEL-3) is completely eluted and removed, and then dried to form a resin film by the first step. It was

Formulation 1 Laxkin 1740-29B 100 parts (Seiko Chemical Co., Ltd., ester type polyurethane resin) Resamine X-100 1 part (Dainichi Seika Chemicals Co., Ltd., isocyanate compound) N, N-dimethylformamide 30 Part Fine gum HEL-3 5 parts (Daiichi Kogyo Seiyaku Co., Ltd., carboxymethyl cellulose)

Next, in the second step, the composition having the composition shown in the following Formulation 2 has a solid content concentration of 25% and a viscosity of 15,000.
A polyurethane resin solution of cp / 25 ° C was applied at a coating amount of 80 g / m ² (dry resin film weight 20 g / m ² ) using a knife over roll coater, and then immediately immersed in water at 15 ° C for 60 seconds. To solidify the resin component, then 50 ℃
After being washed in warm water for 10 minutes, it was dried to obtain the moisture-permeable and waterproof coating cloth of the present invention.

Formulation 2 Resamine CU-4550 100 parts (Dainichi Seika Kogyo Co., Ltd., ester type polyurethane resin) Resamine X-100 1 part (Dainichi Seika Kogyo Co., Ltd., isocyanate compound) N, N-dimethylformamide 25 Part Aerosil R-974 3 parts (manufactured by Nippon Aerosil Co., Ltd., average particle size 0.012 μm,
N, N-dimethylformamide adsorption amount 350 ml / 100 g of hydrophobic silicon dioxide fine powder)

For comparison with the present invention, a moisture-permeable waterproof coating fabric for comparison (comparative example) was prepared in the same manner as in this example except that Finegum HEL-3 was omitted from Formulation 1 in this example. 1) was obtained.

Further, for comparison with the present invention, the first step was omitted in this example, and the resin liquid of the formulation 2 was applied on the calender surface of the base cloth in an amount of 100 g / m ² (dry resin film weight 25
g / m ² except for coating once with), coated fabric for comparison by exactly the same manner as the embodiment (Comparative Example 2
And ) Got.

The performances of the present invention and the coated fabric for comparison were measured and evaluated, and the results are shown together in Table 1.

[0042]

[Table 1]

As is clear from Table 1, the moisture-permeable and waterproof coating fabric produced by the method of the present invention has excellent water pressure resistance and moisture permeability, and has a soft texture even though it is a coated fabric. .

Example 2 A plain fabric having a warp density of 65 yarns / inch and a weft yarn density of 50 yarns / inch using nylon filament 210 denier / 36 filaments for both warp yarns and weft yarns was woven.
A base fabric for coating was obtained by the same method as in Example 1.

Here, as the first step, the following prescription 3
In the composition shown in, the solid content concentration is 20%, the viscosity is 10,000 cp /
The polyurethane resin solution at 25 ° C was applied to the calender surface of the above base fabric with a coating amount of 30 g / m ² (dry resin film weight 6.0 g / m ² ) using a knife coater, and then dried at 80 ° C for 3 minutes. I went.

Formulation 3 Heimren NPU-5 100 parts (Dainichi Seika Kogyo Co., Ltd., one-pack type urethane resin) Isopropyl alcohol 25 parts Toluene 11 parts Duck Algin NSPLL 3 parts (Kibun Food Chemifa Sodium Alginate)

Next, as the second step, in the formulation 2 of Example 1, alumina A was used in place of Aerosil R-974.
KP-G015 (Sumitomo Chemical Co., Ltd., average particle size 0.
03 μm, N, N-dimethylformamide adsorption amount 310
The moisture-permeable waterproof coating fabric of the present invention was produced by the same method as in the second step of Example 1 except that the same amount of milliliter / 100 g of hydrophobic dialuminum trioxide fine powder) was used.

For comparison with the present invention, the coated fabric for comparison (Comparative Example 3) was prepared in exactly the same manner as in this Example, except that the water-soluble substance Duck Algin NSPLL was omitted from Formulation 3 in this Example. I got).

For comparison with the present invention, the first step is omitted in this embodiment, and the second surface is formed on the calender surface of the base cloth.
Coating amount of resin liquid in the process is 100 g / m ² (dry resin film weight 2
A moisture permeable and waterproof coating fabric for comparison (referred to as Comparative Example 4) was obtained in the same manner as in this example except that the coating was applied once at 5 g / m ² ).

The performances of the present invention and the comparative coated fabrics were measured and evaluated, and the results are shown together in Table 2.

[0051]

[Table 2]

As is clear from Table 2, the moisture-permeable and waterproof coating fabric produced by the method of the present invention has excellent water pressure resistance and moisture permeability, and has a soft texture even though it is a coated fabric. .

[0053]

EFFECTS OF THE INVENTION According to the method of the present invention, it is possible to manufacture a moisture-permeable and water-proof coated cloth having excellent water pressure resistance and moisture permeability, and yet enjoy the flexible performance of the texture even though it is a coated cloth. be able to. Further, the coated fabric of the present invention has a performance comparable to the abrasion resistance of the coating resin layer. The coated fabric of the present invention is particularly suitable for rain clothing, because of its excellent performance.
A material suitable for clothing such as outerwear.

Claims (1)

[Claims] 1. A first step in which a synthetic polymer solution containing a polyurethane resin as a main component containing a water-soluble substance is applied onto a fiber cloth to form a wet film or a dry film, and the average particle diameter on the resin film is 1 μm. Second step of applying a synthetic polymer solution mainly composed of a polyurethane resin containing 1% by weight or more of an inorganic fine powder having an adsorption amount of N, N-dimethylformamide of 200 ml / 100 g or more and performing wet film formation A method for producing a moisture-permeable waterproof coating fabric, comprising: