JP3386230B2 - Method for producing coated fabric - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a coated fabric, and more particularly to a waterproof, moisture-permeable, soft-textured, and several-times-washed fabric. The present invention relates to a method for producing a coated fabric having excellent washing durability with excellent water resistance retention rate. [0002] Various waterproof and moisture-permeable coated fabrics have been known so far, and a typical example thereof is a fabric coated with a microporous film made of a polyurethane resin. As a production method, there is a so-called wet coagulation method in which a water-miscible solvent solution of a polyurethane resin is applied to a fiber base material and then immersed in a water bath to form a microporous film made of the polyurethane resin. Kosho 60-4
No. 7955). According to this method, JIS L-1092
JIS Z-020 coating fabric having a water pressure resistance of 1500~3000mm H ₂ O in water pressure resistance measurement equivalent to
The moisture permeability by moisture permeability measurement according to 8 is 7800 to 500
0 g / m ² · 24 hrs, and water resistant pressure of 6500-7
The coating fabric of 500 mm H ₂ O, moisture permeability is obtained of about 5000~3800g / m ² · 24hrs. Further, a coated fabric using a fluorine-modified polyurethane resin or a fluorine-modified polyamino acid resin (JP-A-3-27184) or a coating fabric using a fluorine-modified polyurethane resin and a fluorine resin solution (JP-A-3-8874) Publication), these coated fabrics have a water pressure resistance of 3000 mm H _2.
In O about, moisture permeability 9000~10000g / m ² · ²
It is about 4 hours. Furthermore, a coated fabric obtained by wet coagulation using a polyamino acid resin / urethane resin solution is known to have a water pressure resistance of about 3000 mm H ₂ O and a moisture permeability of about 10,000 g / m ² · 24 hrs. ing. In addition, there has been proposed a method for producing a coated fabric using a mixed solution comprising a fluorine-modified polyurethane resin and a cellulose derivative (Japanese Patent Laid-Open No. 6-2).
No. 278), this method has a water pressure resistance of 700.
Approximately 0mm H ₂ O , moisture permeability 8000g / m ² · 24h
The performance is about rs. [0006] However, conventional coating fabrics made of a resin solution using the above-mentioned polyurethane resin as one component have the following problems in practical use. I have. (1) For example, 3000 mm H before washing.
For coated fabrics having a water pressure resistance of ₂ O , JI
When the water pressure after repeating the washing 10 times according to the automatic washing operation of SL-1096 6.23.1 (Method A) was measured, the water pressure decreased to 600 to 1000 mm H ₂ O ,
Its water resistance retention (%) drops to about 20-30%. [Water resistance retention (%) was calculated by (water resistance after washing / water resistance before washing) × 100]. (2) When a resin solution is applied to a fiber base material to obtain a coated fabric, if a base fabric having a low fiber density is used, the resin solution passes through the base fabric, and a so-called back leakage phenomenon occurs. In addition, when a base cloth having a feeling of unevenness is used, the amount of coating is greatly different between the convex portion and the concave portion, and therefore, the physical properties vary. [0009] (3) To avoid the above (2) problems in obtaining a coating fabric with a base fabric with a lower base fabric and unevenness feeling of the fiber density, acrylic rubber before application of the resin solution system paint or high viscosity, but a high solids polyurethane coating should be thin undercoat base fabric, it processes increases, also the texture of the resulting coating fabric undesirably, and the like. In order to solve the above-mentioned problems in the conventional coated fabric, the present invention uses a material and means completely different from the conventional one to have good water pressure resistance, moisture permeability, and high water resistance retention rate. It is an object of the present invention to provide a coated fabric having excellent washing durability. [0011] Means for Solving the Problems] That is, the present invention is intended to improve the so-called water-resistant retention of the polyurethane coating fabric obtained by wet coagulation method of the resin solution, such as in particular washing resistance, single Monomer has two active hydrogens in the molecule.
Bifunctional monomers and three active hydrogens in the molecule
Is a polyfunctional monomer having the above, and active water in the molecule.
Active polyfunctional monomer having 3 or more elements in the above molecule
0.1 to 3.0 mol of a bifunctional monomer having two hydrogens
%, A water-miscible organic solvent solution of a polyurethane resin comprising these monomers and an organic diisocyanate is applied to at least one surface of the fiber base material, and then immersed in water to extract the water-miscible organic solvent, and then dried. A method for producing a coated fabric. DETAILED DESCRIPTION OF THE INVENTION The present invention, in the production of polyurethane resin solution for coating the fiber substrate to obtain a coating fabric, as the monomer to be reacted with the organic diisocyanate, an active hydrogen in the molecule By using a bifunctional monomer having two and a polyfunctional monomer having three or more active hydrogens in the molecule together, a branched structure of the polyurethane resin is formed and a non-Newtonian resin solution is formed. Because it is obtained, the coated fabric coated with this resin solution can have good water pressure resistance and moisture permeability, and can have high water resistance retention and excellent washing durability. In obtaining a coated fabric, a conventional Newtonian viscous polyurethane resin solution can be used in a coating head of a coating machine between a time immediately after the application of the resin solution to the fiber base material and a time when the resin solution is immersed in water. Due to the pressure applied to the cloth, the capillary action of the fibers that make up the base cloth, and the gravity that is applied perpendicularly to the base cloth surface from the coating surface,
The so-called back leakage phenomenon occurs when the polyurethane resin solution passes through the base cloth. However, in the case of a polyurethane resin solution having a high crosslink density and a non-Newtonian viscosity using a specific elemental component as in the present invention, it does not pass through the base fabric due to its viscosity, and therefore, does not pass through. There is no risk of leakage. [0015] The above-mentioned JISL-1096 6.2 of the coated fabric obtained by applying and drying the resin solution is also used.
In the measurement of the water pressure resistance after washing 10 times in accordance with 3.1 (Method A), the water resistance retention rate of the cloth with the conventional polyurethane resin solution is only about 20 to 30%. In the coated fabric by the manufacturing method of
A high water resistance retention of 70 to 80% can be obtained. This is because, as described above, the polyurethane resin solution of the present invention exhibits non-Newtonian viscosity by using a polyfunctional monomer having three or more active hydrogens in the molecule as an elementary component. This is due to the fact that the crosslink density is increased due to branching of the polymer itself, and the degree of entanglement between molecules and the base fabric fibers in a microscopic sense is superior to conventional polyurethane resin solutions. In general, the viscosity of a polymer solution is given by the equation S = μ
D ⁿ (S: shear stress, μ: non-Newtonian viscosity coefficient, D:
Shear rate, n: non-Newtonian viscosity index, which is given by 1>n> 0), but this measurement is complicated because of effects such as Weissenberg effect, thixotropic, viscoelasticity, etc. And difficult. In the present invention, in order to quantify the non-Newtonian viscosity, a thixotropic index (Thixotropic index) is used.
ic Index) (hereinafter referred to as TI value). This measurement is carried out by measuring the viscosity while changing the number of rotations using a rotational viscometer and calculating the ratio between the two. In the present invention, a BH type viscometer (manufactured by Tokyo Keiki Co., Ltd.) is used. At a constant liquid temperature (30 ° C.) The viscosity of each of the rotations 2 and 20 was measured with a rotor 7 and the ratio between the two was taken as the TI value. As a result of this measurement, the TI value of the polyurethane resin solution having a non-Newtonian viscosity of the present invention was 1.1.
It was found to be in the range of 0 to 2.00, preferably 1.15 to 1.50. This is because when the TI value is larger than 2.00, the liquid stability, the liquid viscosity and the solubility in the solvent are inferior, making it difficult to obtain a uniform resin solution. The non-Newtonian viscosity required in the invention is not obtained, and it is difficult to obtain a coated fabric having the above-described performance. In the present invention, as a main constituent component for obtaining a polyurethane resin solution having a non-Newtonian viscosity and a TI value of 1.10 to 2.00, a monomer to be reacted with an organic diisocyanate is firstly a molecule. As a bifunctional monomer having two active hydrogens therein, a polyalkylene ether glycol having an average molecular weight of 400 to 4000, a polyester polyol having a hydroxyl group at a terminal,
Poly-ε-caprolactone polyol or polycarbonate diol alone or a mixture thereof, and a polyfunctional monomer having three or more active hydrogens in the molecule are used. In the reaction process, two or more By extending the chain with a compound having active hydrogen of
The non-Newtonian polyurethane resin solution of the present invention can be obtained. Examples of the polyalkylene ether glycol include polytetramethylene ether glycol, polypropylene glycol, polyethylene glycol, glycerin propylene oxide adduct, polyether polyol having ethylene oxide added to the terminal, and polyether polyol grafted with vinyl monomer. Examples of polyester polyols include alkylene glycols such as ethylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, and succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, fumaric acid, and phthalic acid. Those obtained by reacting with a carboxylic acid such as an acid or trimellitic acid so that the terminal becomes a hydroxyl group are preferred. Examples of the polyfunctional monomer having three or more active hydrogens in the molecule include polyhydric alcohols such as glycerin, petriol, trimethylolpropane, pentaerythritol, and triethanolamine; iminobispropylamine; Monomers having at least three active hydrogens capable of reacting with an organic diisocyanate in the molecule by the coexistence of polyamines such as ethylenetetramine, alcohols such as diethanolamine and aminoethylethanolamine, and polyalkylene ethers can be used. glycols, a portion of the polyester polyol in the composition is branched, capable of reacting active hydrogen with an organic diisocyanate three or more partial
Those having in the child can also be used. Further, these can be used alone or in combination. As the organic diisocyanate, 2,4-
And 2,6-toluylene diisocyanate, 4,4'-
Aromatic diisocyanates such as diphenylmethane diisocyanate, 1,5-naphthalenediisocyanate, xylylene diisocyanate, isophorone diisocyanate, 1,6-hexamethylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 3-
There are aliphatic diisocyanates such as isocyanatemethyl-3,5,5'-trimethylcyclohexyldiisocyanate and 2,6-diisocyanatomethylcaproate, which are used alone or in combination. The polyurethane resin exhibiting non-Newtonian viscosity in the present invention is desirably blended and reacted so as not to have an isocyanate group at the terminal by using the above-mentioned elementary component, and having an average molecular weight in the range of 30,000 to 120,000. in fact, the amount of the polyfunctional monomer having three or more active hydrogen atoms in the molecule is 0.1 to 3.0 mol% of bifunctional monomer to two chromatic active hydrogen in the molecule Is preferred. [0025] This two have the active hydrogen in the molecule 2
If the amount of the polyfunctional monomer having three or more active hydrogen in the molecule with respect to functional monomer is more than 3.0 mol%, the liquid stability of the resulting resin solution, the liquid viscosity, the solvent A problem occurs in solubility, and it is difficult to obtain a uniform resin solution,
If the amount is less than 0.1 mol%, it is difficult to obtain a non-Newtonian resin solution having a TI value of 1.10 to 2.00, which is a feature of the present invention. In the reaction of the above difunctional monomer or polyfunctional monomer with an organic diisocyanate, hydrazine, ethylenediamine, tetramethylenediamine, water, piperazine, isophoronediamine, ethyleneglycol, butylene may be used, if necessary. Glycol, hexylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol and the like can be used alone or in combination as a chain extender. As the water-miscible organic solvent used in the reaction between the above-mentioned monomer and the organic diisocyanate, dimethylformamide (DMF) is typically used. In addition, dimethylacetamide, N-methylpyrrolidone , Tetrahydrofuran, dioxane and the like can be used alone or in the form of a mixed solvent. In the production of the polyurethane resin of the present invention, a cellulose derivative may be added, if necessary, in order to further improve the water pressure resistance and the moisture permeability. Examples of such a cellulose derivative include cellulose acetate and cellulose acetate. Cellulose esters such as cellulose acetate butyrate and cellulose acetate propionate, and cellulose ethers can be used alone or in combination. In addition, as an additive, a polyfunctional polyisocyanate (for example, trade name Coronate EH, Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.) can be used in order to improve the adhesion to the coating substrate.
It is also effective to add a nonionic surfactant as a speed regulator for removing the solvent in wet coagulation. The polyurethane resin solution having non-Newtonian viscosity obtained in the present invention can be applied to a fiber substrate by a usual coating method.
00 μm is preferred. The water temperature when immersing the fiber base material on which the polyurethane resin film having the above thickness is formed in water is 0 to 30 ° C.
When the temperature is 30 ° C. or higher, the pores of the resin film become large, and the water resistance decreases. The immersion time needs to be 30 seconds or more. If the time is less than 30 seconds, the coagulation of the resin becomes insufficient, which is not preferable. In addition, in order to completely remove the remaining organic solvent, hot water washing may be performed in warm water at 30 to 80 ° C. for 3 to 10 minutes. In addition, by adding a water repellent to the coated fabric obtained by drying after washing with hot water, it is possible to improve the water pressure resistance. As the water repellent, there are various types such as paraffin-based, silicon-based, and fluorine-based, and may be appropriately selected depending on the application, and the application may be performed by a conventional method such as a batting method, a coating method, or a spray method. . According to the above-mentioned method of the present invention, it is possible to obtain a coated fabric excellent in waterproofness and moisture permeability and excellent in washing durability, so-called water resistance retention. Furthermore, a resin solution dispersed or dissolved in an organic solvent solution of a urethane-based resin or a water-based solvent such as a W / O emulsion type polyurethane or an aqueous polyurethane resin is coated on the coated fabric obtained in the present invention by gravure. By overcoating with a printer or a knife coater, it is possible to obtain a coated fabric that has been further subjected to high water pressure resistance. The thus-obtained coated fabric of the present invention can be used for a very wide range of uses such as sportswear such as golf wear and ski wear, winter clothing, rain clothing, and work clothing. Next, the present invention will be described in detail with reference to examples. The present invention is not limited to these embodiments. All parts in the examples are parts by weight. Example 1 300 parts of ethylene butylene adipate having an average molecular weight of 3000 having hydroxyl groups at both terminals, 24.49 parts of ethylene glycol and 0.75 part of triethanolamine were uniformly mixed under a nitrogen stream, and 4 parts of the mixture were added. , 4'-diphenylmethane diisocyanate (hereinafter referred to as MDI)
125 parts and 1800 parts of DMF were added and reacted by heating at 65 ° C. for 6 hours to obtain a polyurethane resin solution having a concentration of 20%. This polyurethane resin solution is subjected to BH at 30 ° C.
Type viscometer, No. When the viscosity was measured with a 7-rotor, 58,000 cps was obtained at a rotation number of 20 and 75,000 cps at a rotation number of 2, and it was confirmed from this value that the resin solution had a TI value of 1.29 and had non-Newtonian viscosity. 100 parts of this polyurethane resin solution was mixed with a polyfunctional polyisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd.).
1 part of Coronate EH) and 30 parts of DMF were added to prepare a coating solution. On the other hand, a wool fabric (taffeta) of 6 nylon fibers as a base material was subjected to batting treatment with a 1% aqueous solution of a fluorine-based water repellent emulsion, followed by heat treatment at 160 ° C. for 1 minute. Next, the coating liquid obtained above was applied to a water-repellent substrate by a floating knife coater for 20 minutes.
0 g / m ² (wet), and then put in a water bath at 20 ° C.
The resin was solidified by immersion for a minute. Then, it was immersed in warm water at 50 ° C. for 10 minutes to sufficiently extract DMF. Subsequently, after drying, batting treatment was performed with a 5% aqueous solution of a fluorine-based water repellent emulsion, and heat treatment was performed at 160 ° C. for 3 minutes to obtain a coated fabric of the present invention. Example 2 300 parts of butylene adipate having an average molecular weight of 3000 having hydroxyl groups at both terminals, ethylene glycol 2
3.93 parts, 7.5 parts of ethylene petriol adipate having an average molecular weight of 3000 having hydroxyl groups at both terminals and in the molecule, and 1.06 part of glycerin were uniformly mixed under a nitrogen stream, and 125 parts of MDI and 1070 parts of DMF were added thereto. Was added thereto and reacted by heating at 75 ° C. for 8 hours to obtain a polyurethane resin solution having a concentration of 30%. The viscosity of this polyurethane resin solution at 30 ° C. was measured in the same manner as in Example 1. As a result, 101500 cps was obtained at a rotation number of 20 and 148000 cps was obtained at a rotation number of 2, and the non-Newtonian viscosity having a TI value of 1.46 was obtained from these values. It was recognized that it had. Using this resin solution, a coated fabric was obtained in the same process as in Example 1. Example 3 600 parts of polycarbonate diol having an average molecular weight of 3000 having hydroxyl groups at both ends, 600 parts of polytetramethylene ether glycol, 6.0 parts of ethylene glycol, 131 parts of dicyclohexylmethane-4,4'-diisocyanate, 131 parts of isophorone Diisocyanate 11
1 part was uniformly mixed under a nitrogen stream, heated and stirred at 115 ° C. for 3.5 hours, and then 84.83 parts of isophoronediamine,
Add 0.08 part of aminoethylethanolamine, 0.03 part of triethyltetramine and 3577 parts of DMF, and add 30 parts.
The mixture was heated and reacted at 1 ° C. for 1 hour to obtain a 30% concentration polyurethane resin solution. The viscosity of this polyurethane resin solution at 30 ° C. was measured in the same manner as in Example 1.
50000 cps at 0, 675 at 2 revolutions
00 cps was obtained, and from this value it was confirmed that the product had a non-Newtonian viscosity with a TI value of 1.35. Using this resin solution, a coated fabric was obtained in the same process as in Example 1. Example 4 300 parts of ethylenebutylene adipate having an average molecular weight of 3000 having hydroxyl groups at both terminals, 24.49 parts of ethylene glycol and 0.67 part of trimethylolpropane were uniformly mixed under a nitrogen stream, and 125 parts of MDI were mixed.
1800 parts of DMF was added and reacted by heating at 75 ° C. for 6 hours.
A 20% strength polyurethane resin solution was obtained. The viscosity of the polyurethane resin solution at 30 ° C. was measured in the same manner as in Example 1.
8500 cps was obtained at ps and a rotation speed of 2. From this value, the TI value was 1.31, and it was confirmed that the product had non-Newtonian viscosity. Using this resin solution, a coated fabric was obtained in the same process as in Example 1. COMPARATIVE EXAMPLE 1 300 parts of ethylene butylene adipate having an average molecular weight of 3000 having hydroxyl groups at both ends and 24.8 parts of ethylene glycol were uniformly mixed under a nitrogen stream.
After adding 125 parts of DI and 1800 parts of DMF, the mixture was heated and reacted at 75 ° C. for 8 hours to obtain a polyurethane resin solution having a concentration of 20%. The viscosity of this polyurethane resin solution at 30 ° C. was measured in the same manner as in Example 1. As a result, the viscosity was 60000 cps at a rotation speed of 20 and 60500 cp at a rotation speed of 2.
s was obtained, and from this value, the TI value was 1.01, and it was confirmed that the product had Newtonian viscosity. Using this resin solution, a coated fabric was obtained in the same process as in Example 1. Comparative Example 2 300 parts of ethylene butylene adipate having an average molecular weight of 3000 having hydroxyl groups at both terminals, 24.78 parts of ethylene glycol and 0.04 part of triethanolamine were uniformly mixed under a nitrogen stream, and 125 parts of MDI were mixed. D
After adding 1800 parts of MF, the mixture was heated and reacted at 65 ° C. for 8 hours.
A polyurethane resin solution having a concentration of 0% was obtained. The viscosity of this polyurethane resin solution at 30 ° C. was measured in the same manner as in Example 1.
At s and the number of rotations of 2, 59000 cps was obtained. From this value, the TI value was 1.07, and it was confirmed that the product had Newtonian viscosity. Using this resin solution, a coated fabric was obtained in the same process as in Example 1. Comparative Example 3 300 parts of ethylene butylene adipate having an average molecular weight of 3000 having hydroxyl groups at both terminals, 23.81 parts of ethylene glycol and 2.38 parts of triethanolamine were uniformly mixed under a nitrogen stream, and 125 parts of MDI were mixed. D
After adding 1800 parts of MF and heating at 60 ° C. for 3 hours, 2
A polyurethane resin solution having a concentration of 0% was obtained. The viscosity of this polyurethane resin solution at 30 ° C. was measured in the same manner as in Example 1.
45500 cps was obtained at s and the number of rotations of 2. From this value, the TI value was 1.62, and it was confirmed that the material had a large non-Newtonian viscosity. Using this resin solution, a coated fabric was obtained in the same process as in Example 1. The performances of the coated fabrics obtained in Examples 1 to 4 and Comparative Examples 1 to 3 such as water pressure resistance and moisture permeability were measured, and the results shown in Table 1 were obtained. The water pressure resistance is J
ISL- 1092 , moisture permeability is JIS Z-0208, washing test is JIS L-1096 6.23.1 (Method A)
The water pressure resistance retention ratio indicates the ratio between the water pressure resistance before washing and the water pressure after washing and drying are repeated 10 times. [Table 1] As is evident from Table 1, the coated fabric obtained by the method of the present invention has good moisture permeability as a moisture-permeable waterproof fabric, and also has a washing test 1
From the value of about 70%, the water resistance retention rate after 0 times was confirmed to have high performance. Further, the coatability of the resin solution to the fiber base material was good, and no back leakage at the time of coating was observed. On the other hand, in the resin solutions obtained in Comparative Examples 1 and 2, a back leakage phenomenon was observed at the time of application to the fiber base material, and only a very low value of the water resistance retention was obtained.
Further, the resin solution of Comparative Example 3 was too viscous and lacked uniform coating properties. As described above, according to the present invention, a polyfunctional monomer having three or more active hydrogens in a molecule is used as a base component for obtaining a polyurethane resin solution. By using a polyurethane resin solution having a non-Newtonian viscosity in the range of 1.10 to 2.00 in combination with a bifunctional monomer having two active hydrogens, the above-described good moisture permeability, A coated fabric having a water resistance retention rate can be obtained, and is suitable for applications such as ski anoraks, sportswear, and raincoats.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) D06M 13/00-15/72

Claims (1)

(57) [Claim 1] The monomer has two active hydrogens in the molecule
Bifunctional monomer and at least 3 active hydrogens in the molecule
Is a multifunctional monomer with three active hydrogens in the molecule.
Active hydrogen is contained in the above molecule in the above-mentioned polyfunctional monomer.
Using 0.1 to 3.0 mol% of the bifunctional monomer having
A water-miscible organic solvent solution of a polyurethane resin comprising these monomers and an organic diisocyanate is applied to at least one surface of the fiber base material, and then the water-miscible organic solvent is extracted by immersion in water, and then dried. A method for producing a coated fabric characterized by the following.