JPH0578984A - Moisture-permeable and waterproof coated cloth - Google Patents

Abstract

PURPOSE:To obtain the title cloth having excellent moisture permeability and waterproof property by subjecting a dispersion consisting mainly of polyurethane resin in which silicon dioxide having a specific form is dispersed at a specific amount or above to wet coating. CONSTITUTION:An uniform dispersion consisting of a polar organic solvent solution of a synthetic polymer consisting mainly of a polyurethane resin in which >=1% pore-free silicon dioxide powder having <=0.1mum average particle diameter is dispersed is applied onto the woven fabric consisting of a synthetic fiber, etc., and dipped in water and coagulated to provide the moisture-permeable waterproof coated cloth having excellent moisture-permeable and waterproof performances. The cloth is suitable for a material for raincoat or overwear, etc., because the cloth is excellent also in wear resistance and release resistance of a coating resin layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating cloth which is used for various kinds of clothes such as rain clothes and outer clothes and which has excellent moisture permeability and waterproof performance.

[0002]

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

In recent years, for the purpose of compensating for the drawbacks of both, a highly moisture-permeable resin layer having a hole is first formed on a fiber cloth, and then a non-porous resin layer is formed on the resin layer, which is excellent. Attempts have been made to obtain moisture-permeable performance and waterproof performance, but in this method, a highly moisture-permeable resin layer having holes has a maximum thickness of 5000 to 6000 even by the wet method.
Only moisture permeability of about g / m ² / 24hrs is obtained, so even if the next non-porous resin layer is applied thinly, the moisture permeability is extremely reduced, resulting in excellent moisture permeability. Currently, it is difficult to achieve both waterproof performance. Further, in this case, coating is performed twice, which is also disadvantageous in terms of processing cost.

On the other hand, in Japanese Patent Laid-Open No. 58-4873 and Japanese Patent Publication No. 62-53632, the average particle diameter of which the main component is silicon dioxide is 2 to 50 μm and the total pore volume is 0.2.
A processing method has been proposed in which a polyurethane resin film containing ˜5 milliliter / g of porous particles is formed, and then a water repellent having a perfluoroalkyl group is added to obtain a moisture permeable waterproof fabric. However, the moisture permeability in any of the methods is at most 3000g / m ² / 24hrs approximately,
Sufficient moisture permeability is not obtained.

Further, Japanese Patent Application Laid-Open No. 2-251672 discloses that it has fine pores smaller than 150Å and has a surface area of 20.
A method of processing a polyester coating fabric with a resin layer in which inorganic porous particles of 0 m ² / g or more, such as silicon dioxide and titanium oxide, are layered and dispersed in a high concentration has been proposed. It only prevents migration of the dye, and does not have sufficient moisture permeability.

[0006]

The present invention has been made in view of the above circumstances, and an object thereof is to obtain a coating cloth having both excellent moisture permeability and waterproof performance.

[0007]

The present invention achieves the above object and has the following constitution. That is, the present invention has a porous resin layer made of a synthetic polymer mainly composed of a 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. the fine powder contains 1% or more, it is an gist moisture-permeable waterproof coating fabric characterized by having a 7000g / m ² / 24hrs or more moisture permeability and 0.6 kg / cm ² or more water pressure resistance .. Hereinafter, the present invention will be described in detail.

The coating fabric of the present invention is characterized in that a fine powder of silicon dioxide is uniformly dispersed and applied in a polar organic solvent solution of a synthetic polymer mainly composed of polyurethane resin,
Next, it is manufactured by a so-called wet coating method in which it is immersed in water to form a resin film, and it is fine and fine without deteriorating the waterproof performance originally possessed by the synthetic polymer mainly composed of polyurethane resin on the fiber cloth as the base cloth. This is where a highly moisture-permeable resin layer with a large number of holes is obtained.

The substantially non-porous silicon dioxide fine powder used in the present invention is generally a silicon dioxide obtained by a dry method such as a gas-phase oxidation method of silicon halide, a combustion hydrolysis method of silicon halide, or an electric arc method. The fine powder obtained by the above method is a hydrophilic substance because it has a large number of silanol groups on the particle surface like other general silicon dioxide fine powders. In the present invention, silicon dioxide fine powder having a large number of silanol groups on the particle surface has sufficient effect, but this hydrophilic silicon dioxide fine powder is uniformly dispersed in a polyurethane polymer-based synthetic polymer solution. The viscosity of the resin solution is likely to become thixotropy, and water is also easily adsorbed, so caution is required in coating operation. Also, since the resin film obtained is hydrophilized, some water leakage may occur. Cause a disadvantage.

In order to make up for these drawbacks, silicon dioxide fine powder is used in the above fine powder, which is made by reacting silanol groups with a substance such as trimethylchlorosilane, dimethyldichlorosilane, ethyl alcohol, isopropyl alcohol and the like to make the fine particle surface hydrophobic. It is effective to use this hydrophobic fine powder, because it does not become so thixotropic and absorbs a small amount of water, so that the substance itself is excellent in stability and advantageous in operation.

Further, the fine powder used in the present invention may be mainly silicon dioxide fine powder, and also contains aluminum oxide, magnesium oxide and the like as impurities or a mixture, general fillers, pigments and the like. There is no problem with it.

The silicon dioxide fine powder used in the present invention is
It means one containing 60% or more as a silicon dioxide component. The fine powder used has an average particle size of 0.1 μm.
It is necessary to be below, and if it is 0.05 μm or less, it is more preferable in terms of effects. If it is larger than 0.1 μm, the pore size of the fine pores of the moisture permeable membrane of the obtained coating fabric becomes too large and the waterproof performance is deteriorated, which is not preferable.

Further, it is necessary that the silicon dioxide fine powder is uniformly contained in the resin layer composed of a synthetic polymer mainly composed of polyurethane resin in an amount of 1% or more, and more preferably 3% or more. When it is less than 1%, the number of fine pores of the moisture permeable membrane of the obtained coating fabric is small and high moisture permeability cannot be obtained.

The fiber cloth used in the present invention includes polyamide synthetic fibers typified by nylon 6 and nylon 66, polyester synthetic fibers typified by polyethylene terephthalate, polyacrylonitrile synthetic fibers,
Woven and knitted fabrics made of polyvinyl alcohol-based synthetic fibers, semi-synthetic fibers such as triacetate, or mixed fibers such as nylon 6 / cotton, polyethylene terephthalate / cotton, etc.
Nonwoven fabrics and the like can be mentioned.

In the present invention, the above-mentioned fiber cloth treated with a water repellent may be used. 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, a fluorine water repellent, or the like, and the treatment thereof is also a commonly used padding method or spray method. It may be performed by a known method such as. When particularly good water repellency is required, a fluorine-based water repellent is used, for example, Asahi Guard 730 (manufactured by Asahi Glass Co., Ltd., a fluorine-based water repellent emulsion) in a 5% aqueous dispersion. Padding (drawing ratio 3
5%), followed by heat treatment at 160 ° C. for 1 minute.

In the coating cloth of the present invention, a synthetic polymer solution mainly containing a polyurethane resin containing silicon dioxide fine powder is applied onto the above-mentioned fiber cloth by a wet coating method. The synthetic polymer mainly composed of polyurethane resin as used herein means one containing 50 to 100% of a polyurethane component, and other synthetic polymers include, for example, polyacrylic acid, polyvinyl chloride, polystyrene, polybutadiene, polyamino acid, etc. Or a copolymer thereof or the like in an amount of less than 50%, and of course, a compound modified with fluorine or silicon can be used in the present invention.

Polyurethane resin is a copolymer obtained by reacting polyisocyanate and polyol,
As the isocyanate component, aromatic diisocyanate,
Using aliphatic diisocyanates and alicyclic diisocyanates alone or in a mixture thereof, for example, trilene
2,4-diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,6-hexane diisocyanate, 1,
4-cyclohexane diisocyanate, etc.,
Polyether polyol and polyester polyol are used as the polyol component, polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like are used as the polyether polyol, and diols such as ethylene glycol and propylene glycol and adipic acid and sebacine are used as the polyester polyol. 2 such as acid
A reaction product with a basic acid or a ring-opening polymer such as caprolactone is used.

The above-mentioned polyurethane polymer-based synthetic polymer solution containing fine particles of silicon dioxide may be appropriately coated using a conventional coating method, for example, a knife coater, a comma coater, a reverse coater or the like. In order to obtain a water pressure resistance of 0.6 kg / cm ² or more, the smoothness and air permeability (JI
Depending on the SL-1096 method), the coating amount is generally adjusted to 5 g / m ² or more, preferably 10 g / m ² or more, and coating is preferably performed.

In the present invention, for the purpose of improving the peel resistance between the resin layer and the fiber cloth, a compound having a high affinity for the resin or the fiber cloth may be used in combination, and an isocyanate compound may be used in combination. .. As the isocyanate compound, 2,4-tolylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate or a compound containing 3 mol of these diisocyanates and active hydrogen (eg, trimethylolpropane, glycerin, etc.) 1 Triisocyanates obtained by addition reaction with moles can be used. The above-mentioned isocyanates may be in a form in which an isocyanate group is released, or in a form in which a block is dissociated by a subsequent heat treatment after being stabilized by adding phenol, methylethylketoxime or the like. However, it can be used, and it may be appropriately used depending on workability and purpose.

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

After the resin liquid consisting of the above-mentioned polyurethane-based synthetic polymer is applied to the fiber cloth, in the present invention,
The resin component is wet-solidified by immersing it in water at 30 ° C. for 0.5 to 10 minutes. Thereafter, after washing in warm water of 40 to 60 ° C. for 5 to 15 minutes, it is dried by a usual method.

In the present invention, for the purpose of further improving the waterproof property, the coating cloth may be subjected to a water repellent treatment after the wet coating. For the water repellent treatment, a publicly known well-known water repellent treatment method as described above may be adopted. Further, when it is desired to further improve the waterproof performance, a dry film thickness of 0.5 is provided on the wet coating layer of the present invention.
A non-porous polyurethane resin layer or the like having a thickness of about 2 μm may be formed. 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.

[0023]

[Working] The moisture-permeable and waterproof coating fabric of the present invention has a resin layer of a synthetic polymer mainly composed of polyurethane resin, and contains substantially non-porous silicon dioxide fine powder having an average particle size of 0.1 μm or less. The result is excellent moisture permeability and waterproof performance. It is not clear why it is possible to obtain both excellent moisture permeability and waterproof performance by including fine particles of silicon dioxide having an average particle size of 0.1 μm or less, but the present inventors presume as follows. ing.

That is, it is substantially non-porous and has an average particle size of 0.1.
When wet-coagulation is performed by coating a cloth with a synthetic polymer solution composed mainly of a polyurethane resin in which fine particles of silicon dioxide having a size of not more than μm are uniformly dispersed, the polyurethane resin forms its unique porous structure and, at the same time, is dissolved in the solution. Since the silicon fine powder is uniformly micro-dispersed, a slight deviation in the solidification rate occurs at the interface between the silicon dioxide fine powder and the resin to be solidified, and as a result, the moisture permeability is improved without lowering the waterproof performance. It is presumed that it becomes possible to provide a large number of fine pores of 1 μm or less which greatly improve the quality.

In the present invention, the moisture permeation performance is improved due to the formed fine perforations, so that water leakage characteristic of a highly moisture-permeable waterproof fabric is likely to occur when pressure is applied during wearing. However, it is very effective. Furthermore, since the silicon dioxide fine powder of the present invention is evenly present from the surface layer to the lower layer of the resin layer, the surface of the resin layer eliminates the slimy feeling peculiar to the polyurethane resin and makes dry touch, and at the same time, Abrasion resistance and adhesive strength are improved.

[0026]

EXAMPLES The present invention will be described in more detail with reference to the following examples. The performance of the coated fabric in the examples was measured by the following method. (1) Water pressure resistance JIS L-1092 (high water pressure method) (2) Water vapor permeability JIS L-1099 (A-1 method) (3) Water leakage According to the Bundesmann method (L-1092 reference test method),
After 120 minutes, the amount of leaked water was measured and the state of the resin film surface due to water penetration was observed. (4) Abrasion strength JIS L-1084 (method A-1) (5) Peel strength A hot melt tape was adhered to the coating surface in the longitudinal direction, and measured according to JIS L-1089 method.

Example 1 Nylon high multifilament 7 for both warp and weft
Weaving a plain woven fabric with a warp density of 120 yarns / inch and a weft yarn density of 90 yarns / inch using a 0 denier 68 filament,
After performing scouring and dyeing (manufactured by Mitsubishi Kasei Co., Ltd., acid dye DiacidFast Red 3BL 2% owf) in the usual manner, Asahi Guard 710, a fluorine-based water repellent agent emulsion
(Asahi Glass Co., Ltd.) After padding with a 5% aqueous solution (squeeze ratio 35%) and drying, heat treatment was performed at 160 ° C. for 1 minute. Next, using a calendering machine having a mirror-finished roll, calendering was carried out under conditions of a temperature of 170 ° C., a pressure of 30 kg / cm ² and a speed of 20 m / min to obtain a base fabric for coating.

Here, a polyurethane resin solution having a composition shown in the following Formulation 1 and a solid content of 25% was applied to the calender surface of the above base cloth by using a knife over roll coater in an amount of 8
Immediately after application at 0 g / m ²
The resin component was solidified by dipping for a second, followed by washing in warm water at 50 ° C. for 10 minutes and drying to form a resin layer containing 11% of silicon dioxide fine powder. [Formulation 1] 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 parts Aerosil R-974 3 parts (manufactured by Nippon Aerosil Co., Ltd., hydrophobic silicon dioxide fine powder with an average particle size of 0.012 μm)

Next, using a gravure coater, the coated surface is gravure coated with a 5% aqueous solution of Asahi Guard 710 to make the coating surface water repellent, dried and then heat-treated at 160 ° C. for 1 minute to obtain the coating fabric of the present invention. Got

For comparison with the present invention, a comparative coating fabric (referred to as Comparative Example 1) was obtained in exactly the same manner as in this Example except that Aerosil R-974 was omitted from Formulation 1 in this Example. It was For comparison with the present invention,
Instead of Aerosil R-974 in Formulation 1 of this Example, crushed product of Kieselgel 60G (manufactured by MERCK, particle size 1
A coating cloth for comparison (Comparative Example 2) was prepared in the same manner as in this Example except that a resin layer containing 17% was formed by using 5 parts of SiO ₂ .nH ₂ O fine powder of 10 μm.
I got).

The performances of the coating fabrics of the present invention and Comparative Examples 1 and 2 were measured and evaluated, and the results are shown in Table 1.

[Table 1]

As is clear from the results shown in Table 1, the coating fabric of the present invention has excellent water pressure resistance and moisture permeability, and by applying hydrophobic silicon dioxide fine powder, the highly moisture permeable waterproof fabric is obtained. It can be seen that it is very effective against water leakage, which is a drawback of, and has good wear resistance and peeling resistance.

Here, the film formed for reference will be described with a cross-sectional photograph. 1 and 2 are photographs showing a cross section of a microporous film formed on the surface of a moisture-permeable and waterproof coating cloth of the present invention, magnified 1000 times and 10000 times by a scanning electron microscope, respectively. 3 is a scanning electron micrograph of a cross section of a polyurethane film containing no silicon dioxide fine powder formed on the surface of the coating fabric of Comparative Example 1 at a magnification of 1000 times. The moisture-permeable waterproof coating fabric of the present invention has a large number of fine pores of 1 μm or less, as is clear from comparing the photographs of FIGS. 1 and 2 with the photograph of FIG. On the other hand, in the photograph of FIG. 3 of the comparative example, since the fine pores do not exist at all, the moisture permeability is extremely low.

Example 2 The same amount of Aerosil # 200 (manufactured by Nippon Aerosil Co., Ltd., hydrophilic silicon dioxide fine powder having an average particle size of 0.012 μm) was used in place of Aerosil R-974 in Formulation 1 of Example 1 above. Except for the above, the moisture-permeable and waterproof coating fabric of the present invention was obtained by the same method as in Example 1.

For comparison with the present invention, a comparative coating fabric (Comparative Example 3) was prepared in exactly the same manner as this Example except that Aerosil # 200 was omitted from the coating resin liquid formulation in this Example. Obtained. Further, for comparison with the present invention, in the coating resin liquid formulation of this example, a crushed product of Kieselgel 60G was used instead of Aerosil # 200 (manufactured by MERCK, SiO _{2 having} a particle size of 1 to 10 μm).
A coating fabric for comparison (referred to as Comparative Example 4) was obtained by the same method as in this Example except that 5 parts of (nH ₂ O fine powder) was used to form a resin layer containing 17%.

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

[Table 2]

As is clear from Table 2, the coating fabric of the present invention has excellent water pressure resistance and moisture permeability, and also has good water leakage, abrasion resistance and peeling resistance.

[0038]

According to the method of the present invention, it is possible to obtain a coated cloth having excellent moisture permeability and waterproof performance. Further, the coating fabric of the present invention is excellent in abrasion resistance and peeling resistance of the coating resin layer. According to the present invention, since high performance can be obtained in terms of both moisture permeability and waterproofness only by wet coating, it can be manufactured at low cost, which is very advantageous in industry. The coating fabric of the present invention is a material suitable for apparel such as rain clothes and outer garments because of its excellent performance.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional photograph of a film obtained by enlarging a cross section of a microporous film in the moisture-permeable waterproof coating fabric of the present invention obtained in Example 1 by 1000 times with a scanning electron microscope.

FIG. 2 is an enlarged cross-sectional photograph of the film obtained by enlarging the cross section of the microporous film in the moisture-permeable and waterproof coating fabric of the present invention obtained in Example 1 by 10000 times with a scanning electron microscope.

FIG. 3 is an enlarged cross-sectional photograph of a film obtained by magnifying a cross-section of the film in the comparative coating fabric obtained in Comparative Example 1 by 1000 times with a scanning electron microscope.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B32B 27/20 Z 6122-4F 27/40 7016-4F D06M 11/79 D06N 3/14 102 7141- 4F

Claims (1)

[Claims] 1. A silicon dioxide fine particle having a porous resin layer made of a synthetic resin mainly composed of a polyurethane resin on a fiber cloth, wherein the resin layer is substantially non-porous and has an average particle diameter of 0.1 μm or less. powder containing more than 1%, 7000g / m ² / 24hrs or more moisture permeability and 0.6 kg / cm ² or more moisture-permeable waterproof coating fabric characterized by having a water pressure resistance.