JP5768043B2 - Polyurethane resin aqueous dispersion, nonporous film, moisture-permeable waterproof fabric, and method for producing the same - Google Patents

Description

The present invention relates to an aqueous polyurethane resin dispersion used for a nonporous film of a moisture-permeable waterproof fabric, a nonporous film, a moisture-permeable waterproof fabric, and a method for producing the same.
This application claims priority based on Japanese Patent Application No. 2010-98875 filed in Japan on April 22, 2010, the contents of which are incorporated herein by reference.

A moisture-permeable waterproof fabric having a nonporous urethane resin film is widely used because it has excellent waterproof properties.
A moisture-permeable waterproof fabric is generally formed by applying a polyurethane resin solution on a release paper and heating to form a nonporous film, and laminating the nonporous film and a fiber fabric using an adhesive. It is manufactured by the method (laminate method).

Conventionally, as a polyurethane resin solution, a solution obtained by dissolving a polyurethane resin in an organic solvent such as dimethylformamide, toluene, or methyl ethyl ketone has been used. However, since a large amount of volatile organic compound (VOC) is discharged due to heating when forming a nonporous film and the load on the environment is large, an aqueous polyurethane resin dispersion in which a polyurethane resin is dispersed in water is used. It has been desired to develop a moisture-permeable waterproof fabric.
However, when an aqueous polyurethane resin dispersion is used, the load on the environment is smaller than when a polyurethane resin solution dissolved in an organic solvent is used, but it is inferior in terms of moisture permeability and washing resistance. There was a problem.
In the present invention, “inferior washing resistance” means that after washing a moisture-permeable waterproof fabric, the non-porous film has lower moisture permeability or water pressure resistance than before washing, and swelling or whitening is observed in the nonporous film. Or the case where the nonporous film has peeled from the fiber fabric is said.

As a countermeasure against such a problem, conventionally, for example, a neutralized product of an isocyanate group-terminated prepolymer obtained by reacting a polyisocyanate compound, a polyol compound having an oxyethylene group, and a diol compound having a carboxy group is water. An aqueous polyurethane resin dispersion obtained by performing chain extension reaction in water using at least one compound selected from water-soluble polyamines, hydrazine and derivatives thereof after dispersion is disclosed (see Patent Document 1).
In the invention described in Patent Document 1, the water pressure resistance and washing resistance of a moisture-permeable waterproof fabric are improved by using a polyurethane resin aqueous dispersion in combination with a specific crosslinking agent that undergoes a crosslinking reaction with a carboxy group. (Example 4 etc.).

JP 2004-300188 A

However, in the aqueous polyurethane resin dispersion disclosed in Patent Document 1, in order to impart sufficient water dispersibility to the polyurethane resin, a large amount of carboxy groups exceeding 1% by mass with respect to the polyurethane resin. Has been introduced. The moisture-permeable waterproof fabric manufactured using a polyurethane resin having a large amount of carboxy groups introduced in this way is difficult to obtain high water pressure resistance, and therefore satisfies all of moisture permeability, water pressure resistance and washing resistance. Have difficulty.
In the invention described in Patent Document 1, a specific cross-linking agent must be used to achieve high water pressure resistance and washing resistance.

  The present invention has been made in view of the above circumstances, and even when a crosslinking agent is not used, a moisture-permeable waterproof fabric excellent in moisture permeability, water pressure resistance, and washing resistance, a method for producing the same, and It is an object of the present invention to provide a polyurethane resin aqueous dispersion suitable for use in a nonporous film of a moisture-permeable waterproof fabric and a nonporous film formed by heating the polyurethane resin aqueous dispersion.

As a result of intensive studies, the present inventors have adopted the following configuration in order to solve the above problems.
That is, the first aspect of the present invention includes polytetramethylene ether glycol (A), polyol (B) having an oxyethylene group, alkylene diol (C) having a branched alkylene group, and organic polyisocyanate. Polyurethane used for a nonporous film of a moisture-permeable waterproof fabric in which a polyurethane resin obtained by reacting (D) with an isocyanate group-terminated urethane prepolymer and a chain extender (F) is dispersed in water An aqueous resin dispersion having a particle diameter of not more than 500 nm at 90% cumulative accumulation, the polyurethane resin having an oxyethylene group content of 20 to 30% by mass relative to the polyurethane resin, and a carboxy group It is the 1st polyurethane resin aqueous dispersion which does not contain.

  The second aspect of the present invention includes a polytetramethylene ether glycol (A), a polyol (B) having an oxyethylene group, an alkylene diol (C) having a branched alkylene group, an organic polyisocyanate (D), Non-porous moisture-permeable waterproof fabric in which a polyurethane resin obtained by a chain extension reaction of an isocyanate group-terminated urethane prepolymer produced by a reaction with a polyol (E) having a carboxy group is dispersed in water Polyurethane resin aqueous dispersion for use in a porous film, the particle diameter at 90% cumulative passage is 500 nm or less, and the polyurethane resin has an oxyethylene group content of 20 to 30% by mass relative to the polyurethane resin. And carboxy group content is 1.0 mass% or less with respect to this polyurethane resin. 2 of a polyurethane resin aqueous dispersion.

Moreover, the 3rd aspect of this invention is a nonporous film formed by heating the polyurethane resin aqueous dispersion of said 1st or 2nd aspect.
The fourth aspect of the present invention is a moisture-permeable waterproof fabric having the nonporous film of the present invention and a fiber fabric.

  The fifth aspect of the present invention is a method for producing a moisture-permeable waterproof fabric according to the third aspect of the present invention, wherein the polyurethane resin aqueous dispersion is applied to at least one surface of a release sheet and heated. Forming a nonporous film, applying an adhesive to at least one surface of the nonporous film and the fiber fabric, and bonding the nonporous film and the fiber fabric to the adhesive. A method for producing a moisture-permeable waterproof fabric having a step of adhering via an adhesive.

ADVANTAGE OF THE INVENTION According to this invention, even if it is a case where a crosslinking agent is not used, the moisture-permeable waterproof fabric excellent in all of moisture permeability, water pressure resistance, and washing resistance and its manufacturing method can be provided.
Moreover, according to this invention, the polyurethane resin aqueous dispersion suitable for using for the nonporous film of a moisture-permeable waterproof fabric, and the nonporous film formed by heating this can be provided.

≪Polyurethane resin aqueous dispersion (1) ≫
The polyurethane resin aqueous dispersion (hereinafter referred to as “polyurethane resin aqueous dispersion (1)”) used for the nonporous film of the moisture-permeable waterproof fabric, which is the first aspect of the present invention, is polytetramethylene ether glycol (A). ), A polyol (B) having an oxyethylene group, an alkylene diol (C) having a branched alkylene group, and an organic polyisocyanate (D) are produced by reacting an isocyanate group-terminated urethane prepolymer with a chain extender ( A polyurethane resin obtained by chain extension reaction with F) is dispersed in water.

<Polytetramethylene ether glycol (A)>
As polytetramethylene ether glycol (A) (hereinafter referred to as “component (A)”), for example, those having a number average molecular weight of 500 to 6000 are preferred, and those having 1000 to 3000 are more preferred.
When the number average molecular weight is less than 500, the nonporous film tends to be hard or moisture permeability is lowered when the nonporous film is formed. On the other hand, when the number average molecular weight exceeds 6000, the water pressure resistance of the nonporous film tends to be lowered.
In the present invention, the “number average molecular weight” is a number average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

<Polyol (B) having an oxyethylene group>
Examples of the polyol (B) having an oxyethylene group (hereinafter referred to as “component (B)”) include polyethylene glycol, polyoxyethylene polyoxypropylene glycol, and the like.
The content of the oxyethylene group contained in the component (B) is preferably 50% by mass or more and more preferably 70 to 100% by mass with respect to the component (B) because it can impart more excellent moisture permeability.
Moreover, as (B) component, the thing of a number average molecular weight 400-5000 is preferable, and the thing of 500-3000 is more preferable, for example.
When the number average molecular weight is less than 400, the moisture permeability of the nonporous film tends to decrease when the nonporous film is formed. On the other hand, when the number average molecular weight exceeds 5,000, the particle diameter of the polyurethane resin aqueous dispersion tends to increase, and the water pressure resistance of the nonporous film tends to decrease.

<Alkylenediol (C) having a branched alkylene group>
By using an alkylene diol (C) having a branched alkylene group (hereinafter referred to as “component (C)”), it is possible to obtain a polyurethane resin aqueous dispersion having a small particle size while increasing the dispersibility of the polyurethane resin in water. Can do. Moreover, the water pressure resistance of the moisture-permeable waterproof fabric is good.
Examples of the component (C) include 2,2-dimethylpropanediol, 3-methyl-1,5-pentanediol, 1,2-propylene glycol, 2-methyl-1,3-propanediol, 2,3- Examples include butanediol, 3-methyl-1,3-butanediol, and 2-methyl-1,8-octanediol. Especially, since the said effect obtained by using (C) component is high, 3-methyl- 1,5-pentanediol is preferable.

<Organic polyisocyanate (D)>
Examples of the organic polyisocyanate (D) (hereinafter referred to as “component (D)”) include aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate; xylylene diisocyanate, tetramethylxylylene diisocyanate, and the like. Aromatic aliphatic polyisocyanates; aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate and the like.
Moreover, as (D) component, modified bodies, such as the dimer of the said organic polyisocyanate, a trimer, or buret-ized isocyanate, are mentioned.
Of these, for example, aliphatic polyisocyanates and araliphatic polyisocyanates are preferable, and aliphatic polyisocyanates are more preferable because yellowing due to long-term use of a nonporous film in a moisture-permeable waterproof fabric can be suppressed.

<Chain extender (F)>
Examples of the chain extender (F) (hereinafter referred to as “component (F)”) include polyamine compounds such as ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, diethylenetriamine, dipropylenetriamine, and triethylenetetramine; adipic acid And hydrazide compounds such as dihydrazide, hydrazine and the like.

(Method for producing aqueous polyurethane resin dispersion (1))
The polyurethane resin aqueous dispersion (1) is, for example, an isocyanate group-terminated urethane prepolymer solution (hereinafter referred to as “prepolymer solution (1)” by reacting the components (A) to (D) in an organic solvent. ), The prepolymer solution (1) is dispersed in water to prepare a prepolymer dispersion (1), and then the component (F) is added to cause chain extension reaction.

  As the organic solvent, those which can lower the viscosity of the reaction solution and are inert to the isocyanate group are preferable. For example, dimethylformamide, dimethyl sulfoxide, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, tetrahydrofuran, dioxane, ethyl acetate And butyl acetate.

  The amount of each component used is preferably 20 to 60 parts by mass, more preferably 25 to 50 parts by mass, and (B) component 10 to 100 parts by mass of the polyurethane resin. It is preferably ~ 40 parts by mass, more preferably 20-30 parts by mass, and the component (C) is preferably 0.5-15 parts by mass, more preferably 1-13 parts by mass. Preferably, the component (D) is preferably 20 to 40 parts by mass, more preferably 25 to 35 parts by mass, and the component (F) is preferably 0.5 to 10 parts by mass, The amount is more preferably 8 parts by mass, and the organic solvent is preferably 40 to 150 parts by mass, and more preferably 60 to 100 parts by mass.

The reaction conditions for reacting the components (A) to (D) in an organic solvent may be reaction conditions for synthesizing a general polyurethane resin. For example, the reaction temperature is 20 to 100 ° C. The reaction time is preferably 60 to 80 ° C., the reaction time is preferably 30 minutes or more and 12 hours or less, and more preferably 1 to 5 hours.
The free isocyanate group (f-NCO) content in the resulting isocyanate group-terminated urethane prepolymer is preferably 1 to 4% by mass with respect to the isocyanate group-terminated urethane prepolymer, and 1.5 to 3.5% by mass. % Is more preferable.
In this invention, free isocyanate group (f-NCO) content shows the value measured by the method based on JISK7301.

The prepolymer dispersion (1) can be prepared by gradually adding water to the prepolymer solution (1) while stirring the prepolymer solution (1) with an emulsifier such as a homogenizer.
The temperature condition for preparing the prepolymer dispersion (1) is preferably 10 to 50 ° C, and more preferably 20 to 40 ° C.
The amount of water used is preferably 200 to 600 parts by mass and more preferably 300 to 500 parts by mass with respect to 100 parts by mass of the prepolymer component.

The reaction temperature during the chain extension reaction is preferably 10 to 35 ° C, more preferably 20 to 30 ° C.
The reaction time for the chain extension reaction is preferably 0.5 to 3 hours, and more preferably 1 to 2 hours.

  After the chain extension reaction, the organic solvent is distilled off under reduced pressure to obtain an aqueous polyurethane resin dispersion (1) containing substantially no organic solvent.

The polyurethane resin contained in the aqueous polyurethane resin dispersion (1) has an oxyethylene group content of 20 to 30% by mass and preferably 22 to 28% by mass with respect to the polyurethane resin.
When the oxyethylene group content is less than 20% by mass, the moisture permeability of the moisture-permeable waterproof fabric tends to decrease. On the other hand, when the oxyethylene group content exceeds 30% by mass, The water pressure resistance tends to decrease. In addition, due to washing, for example, a non-porous film in a moisture-permeable waterproof fabric is likely to have poor appearance or peeling from the fiber fabric.
In the present invention, the “oxyethylene group content” is calculated from the charged amount of the raw material, specifically, a value calculated from the content of the oxyethylene group in the component (B) with respect to the total amount of the charged raw material. Shown (same below).

  The polyurethane resin contained in the aqueous polyurethane resin dispersion (1) does not contain a carboxy group. By not containing a carboxy group, it becomes easy to obtain a moisture-permeable waterproof fabric with high water pressure resistance.

  The concentration (solid content) of the polyurethane resin contained in the aqueous polyurethane resin dispersion (1) is preferably 10 to 40% by mass, and more preferably 20 to 35% by mass.

The aqueous polyurethane resin dispersion (1) of the present invention has a particle size at a passing accumulation of 90% of 500 nm or less, preferably 300 nm or less, more preferably 100 nm or less. When the particle diameter exceeds 500 nm, for example, when a nonporous film is formed, it becomes difficult to obtain a uniform nonporous film, which tends to cause poor appearance and reduced water pressure resistance.
On the other hand, the lower limit of the particle size is preferably 10 nm or more because the viscosity of the polyurethane resin aqueous dispersion increases as the particle size decreases.
In the present invention, “particle diameter at 90% cumulative passage” indicates a value measured at a temperature of 20 ° C. using a microtrack (trade name: UPA150, manufactured by Nikkiso Co., Ltd.).
In order to control the particle diameter of the polyurethane resin aqueous dispersion (1) at 90% cumulative accumulation to 500 nm or less, for example, a method of increasing or decreasing the amount of the (B) component, (C) component or (F) component used is used. That's fine.

≪Polyurethane resin aqueous dispersion (2) ≫
The polyurethane resin aqueous dispersion (hereinafter referred to as “polyurethane resin aqueous dispersion (2)”) used for the nonporous film of the moisture-permeable waterproof fabric, which is the second aspect of the present invention, is polytetramethylene ether glycol (A). ), A polyol (B) having an oxyethylene group, an alkylene diol (C) having a branched alkylene group, an organic polyisocyanate (D), and a polyol (E) having a carboxy group, are formed. A polyurethane resin obtained by chain extension reaction of the base terminal urethane prepolymer with the chain extender (F) is dispersed in water.

  For polytetramethylene ether glycol (A), polyol (B) having an oxyethylene group, alkylene diol (C) having a branched alkylene group, organic polyisocyanate (D) and chain extender (F), the above (A) It is the same as each of the components (D) to (F).

<Polyol (E) having a carboxy group>
The polyol (E) having a carboxy group (hereinafter referred to as “component (E)”) is a compound having one or more carboxy groups and two or more hydroxyl groups in the molecule.
By using the component (E), the dispersibility of the polyurethane resin in water can be further improved, and the particle diameter of the polyurethane resin can be further reduced.
Examples of the component (E) include dialkanol carboxylic acids such as 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, and 2,2-dimethylolvaleric acid.

(Production method of aqueous polyurethane resin dispersion (2))
The polyurethane resin aqueous dispersion (2) is referred to as an isocyanate group-terminated urethane prepolymer solution (hereinafter referred to as “prepolymer solution (2)”) by, for example, reacting the components (A) to (E) in an organic solvent. The prepolymer solution (2) is preferably neutralized with a tertiary amine compound, and the prepolymer solution after neutralization is dispersed in water to prepare a prepolymer dispersion (2). Then, it can be produced by adding the component (F) and causing a chain extension reaction.

By neutralizing the prepolymer solution (2) using the tertiary amine compound, the dispersibility of the polyurethane resin in water can be further improved, and the particle diameter of the polyurethane resin can be further reduced.
Examples of the tertiary amine compound include trialkylamines such as trimethylamine and triethylamine; and alkanolamines such as dimethylaminoethanol, triethanolamine and tripropanolamine. Among these, a trialkylamine is preferable because the water pressure resistance of the moisture-permeable waterproof fabric is more excellent.
The neutralization performed using the tertiary amine compound may be before the reaction of the components (A) to (E), may be in the middle of the reaction, or may be performed after the preparation of the prepolymer solution (2). May be.

The amount of the components (A) to (D), the component (F) and the organic solvent used in the production of the aqueous polyurethane resin dispersion (2) is the same as in the production method of the aqueous polyurethane resin dispersion (1). is there.
(E) It is preferable that it is 0.01-3 mass parts with respect to 100 mass parts of polyurethane resins, and, as for the usage-amount of a component, it is more preferable that it is 0.1-1 mass part.
The amount of the tertiary amine compound used is preferably 0.01 to 5 parts by mass and more preferably 0.1 to 3 parts by mass with respect to 100 parts by mass of the polyurethane resin.

  Kind of organic solvent, reaction conditions (temperature, time) when reacting the components (A) to (E) in the organic solvent, free isocyanate group (f-NCO) content in the isocyanate group-terminated urethane prepolymer, The preparation method of the prepolymer dispersion (2) and the reaction conditions (temperature, time) for the chain extension reaction are the same as those in the production method of the polyurethane resin aqueous dispersion (1).

  After the chain extension reaction, the organic solvent is distilled off under reduced pressure to obtain an aqueous polyurethane resin dispersion (2) substantially free of organic solvent.

The polyurethane resin contained in the aqueous polyurethane resin dispersion (2) has an oxyethylene group content of 20 to 30% by mass and preferably 22 to 28% by mass with respect to the polyurethane resin.
When the oxyethylene group content is less than 20% by mass, the moisture permeability of the moisture-permeable waterproof fabric tends to decrease. On the other hand, when the oxyethylene group content exceeds 30% by mass, The water pressure resistance tends to decrease. In addition, due to washing, for example, a non-porous film in a moisture-permeable waterproof fabric is likely to have poor appearance or peeling from the fiber fabric.

The polyurethane resin contained in the aqueous polyurethane resin dispersion (2) has a carboxy group content of 1.0% by mass or less, preferably 0.5% by mass or less, based on the polyurethane resin. More preferably, it is 29 mass% or less. When the carboxy group content is 1.0% by mass or less, even when a crosslinker is not used when forming a nonporous film using the polyurethane resin aqueous dispersion (2), the water resistance is high. Pressure can be obtained. In addition, the appearance of the nonporous film is hardly caused by washing.
On the other hand, the lower limit of the carboxy group content is preferably 0.01% by mass or more because the dispersibility of the polyurethane resin in water is further improved and the particle diameter of the polyurethane resin can be further reduced.
In the present invention, the “carboxy group content” is calculated from the charged amount of the raw material, and specifically represents a value calculated from the content of the carboxy group in the component (E) with respect to the total amount of the charged raw material ( same as below).

  Regarding the concentration (solid content) of the polyurethane resin contained in the aqueous polyurethane resin dispersion (2), the particle diameter at 90% of cumulative passage of the aqueous polyurethane resin dispersion (2), and the control method thereof, the aqueous polyurethane resin dispersion ( The same applies to the concentration (solid content) of the polyurethane resin contained in 1), the particle diameter at 90% cumulative passage of the aqueous polyurethane resin dispersion (1), and its control method.

In addition, the manufacturing method of polyurethane resin aqueous dispersion (1) or polyurethane resin aqueous dispersion (2) is not limited to the manufacturing method mentioned above, For example, said (A)-(D) component or (A)- The component (E) may be reacted without a solvent, or a urethanization promoting catalyst such as dioctyltin dilaurate may be used.
In addition, in the production of the aqueous polyurethane resin dispersion (1) or the aqueous polyurethane resin dispersion (2), other polyols and monools other than the components (A) to (C) can be used.
Examples of other polyols include polyether polyols, polyester polyols, and polycarbonate polyols having no oxyethylene group; 1,4-butanediol, 1,6-hexanediol, propylene glycol, glycerin, trimethylolpropane. , Pentaerythritol, sorbitol and the like.
Examples of monools include methanol, ethanol, ethylene glycol monomethyl ether, and the like.
In addition, in the production of the aqueous polyurethane resin dispersion (1) or the aqueous polyurethane resin dispersion (2), a surfactant, antioxidant, light resistance improver, leveling agent, Additives such as film assistants, thickeners and antiblocking agents can also be used.

≪Nonporous film≫
The nonporous film of the present invention is formed by heating the aqueous polyurethane resin dispersion (1) or the aqueous polyurethane resin dispersion (2).
The nonporous film can be produced by the same operation as the step of forming the nonporous film in << Method for producing moisture-permeable waterproof fabric >> described later.
When the nonporous film is used for a moisture-permeable waterproof fabric, excellent moisture permeability is obtained. Therefore, the moisture permeability in terms of 24-hour conversion according to the JIS L 1099 B-1 method (potassium acetate method) is 50000 g / (m ² · 24 hours) or more, more preferably 60000-200000 g / (m ² · 24 hours).
In addition, since the nonporous film can impart excellent water pressure resistance when used in a moisture-permeable waterproof fabric, the water pressure resistance according to JIS L 1092 (water resistance test (hydrostatic pressure method) B method (high water pressure method)). The degree is preferably 100 kPa or more, and more preferably 150 kPa or more. The upper limit value of the water pressure resistance is preferably as high as possible, but the upper limit value is several hundred kPa or less due to the influence of the taffeta overlaid on the nonporous film when the water pressure resistance is measured.

≪Moisture permeable waterproof fabric≫
The moisture-permeable waterproof fabric of the present invention has the nonporous film of the present invention and a fiber fabric.
As a material for the fiber fabric, for example, polyester, nylon, polyurethane, acrylic, rayon, cotton and the like can be used. Examples of the material include woven fabric, knitted fabric, non-woven fabric, and raised fabric. In addition, the woven fabric, the knitted fabric or the like may be obtained from a single material, or may be a mixture of two or more materials, blended fiber, mixed fabric, woven fabric, or knitted fabric.
Note that the fiber fabric may be subjected to dyeing, printing, antibacterial and deodorizing processing, antibacterial processing, ultraviolet shielding processing, water repellent treatment, and the like.
Since the moisture-permeable waterproof fabric of the present invention has excellent moisture permeability, the moisture permeability in terms of 24 hours according to the JIS L 1099 B-1 method (potassium acetate method) is 10,000 g / (m ² · 24 hours) or more. It is preferably 10,000 to 200,000 g / (m ² · 24 hours).
Since the moisture-permeable waterproof fabric has excellent water pressure resistance, the water pressure resistance according to JIS L 1092 (water resistance test (hydrostatic pressure method) B method (high water pressure method)) is preferably 150 kPa or more, and 160 kPa. More preferably. The upper limit value of the water pressure resistance is preferably as high as possible, and is substantially about 1000 kPa or less although it varies depending on the fiber fabric constituting the moisture-permeable waterproof fabric.
Since the moisture-permeable waterproof fabric has excellent washing resistance, the moisture-permeable waterproof fabric after washing 10 times according to the number 103 of JIS L 0217 Attached Table 1 has a moisture permeability of 10,000 g / (m ^2. 24 hours) or more, preferably 15000 g / (m ² · 24 hours) or more, more preferably 15000 to 200000 g / (m ² · 24 hours), and the water pressure resistance The degree is preferably 100 kPa or more, and more preferably 140 kPa or more. The upper limit of the water pressure resistance is preferably as high as possible, and is substantially about 1000 kPa or less, although it varies depending on the fiber fabric constituting the moisture-permeable waterproof fabric.
The moisture-permeable waterproof fabric of the present invention is excellent in moisture permeability, water pressure resistance and washing resistance. Moreover, in the moisture-permeable waterproof fabric of this invention, external appearance defects, such as expansion | swelling and cloudiness, and peeling from the fiber fabric of a nonporous film do not generate | occur | produce easily.

In the polyurethane resin aqueous dispersion (1) or the polyurethane resin aqueous dispersion (2) described above, specific (A) to (D) components and (F) components, or (A) to (F) components are used. In particular, by using the component (C) (alkylene diol having a branched alkylene group), it is possible to obtain a polyurethane resin aqueous dispersion having excellent dispersion of water in a polyurethane resin and a small particle diameter. .
Further, the polyurethane resin aqueous dispersion (1) or the polyurethane resin aqueous dispersion (2) contains a polyurethane resin containing no carboxy group or having a carboxy group content of 1.0% by mass or less.
By using such an aqueous polyurethane resin dispersion (1) or aqueous polyurethane resin dispersion (2), a nonporous film having high moisture permeability and high water pressure resistance can be prepared even when a crosslinking agent is not used in combination. And the moisture-permeable waterproof fabric which has the said nonporous film becomes excellent in all of moisture permeability, water pressure resistance, and washing resistance.

≪Method for producing moisture-permeable waterproof fabric≫
Specifically, the moisture-permeable waterproof fabric of the present invention can be produced as follows.
That is, the moisture-permeable waterproof fabric includes a step of forming the nonporous film by applying the polyurethane resin aqueous dispersion on at least one surface of a release sheet and heating, and the nonporous film and the fiber. It can be produced by a method comprising a step of applying an adhesive to at least one surface of the fabric, and a step of bonding the nonporous film and the fiber fabric through the adhesive.

A conventionally well-known thing can be used for a release sheet, for example, the release paper surface-treated with polypropylene, the polyester film which has mold release property, etc. can be used.
The polyurethane resin aqueous dispersion (1) or (2) can be applied to the release sheet surface by a conventionally known method such as knife coating, comma coating, or bar coating.
The heating after applying the polyurethane resin aqueous dispersion (1) or (2) is, for example, preheating at 60 to 100 ° C. for 0.5 to 3 minutes, and then at 100 to 150 ° C. for 1 to 3 minutes. This can be done by heating. By such heat treatment, a nonporous film formed by drying and forming the polyurethane resin aqueous dispersion (1) or (2) is formed on at least one surface of the release sheet.

The film thickness of the nonporous film is preferably 3 to 50 μm, and more preferably 5 to 30 μm. When the film thickness of the nonporous film is 50 μm or less, moisture permeability is improved, and when it is 3 μm or more, the water pressure resistance is improved.
The film thickness of the nonporous film is determined by adjusting the size of the slit of a knife coater or the like used when applying the polyurethane resin aqueous dispersion on the release sheet, or by repeatedly applying and heating the polyurethane resin aqueous dispersion. It can control by the method to do.

  In particular, when the polyurethane resin contains a carboxy group (that is, when the polyurethane resin aqueous dispersion (2) is used), a carbodiimide crosslinking agent, an epoxy crosslinking agent, an oxazoline crosslinking agent, etc. The crosslinking agent may be used together with the polyurethane resin aqueous dispersion (2). However, in the present invention, even if the crosslinking agent is not used, the moisture permeability excellent in moisture permeability, water pressure resistance and washing resistance. A waterproof fabric can be manufactured.

  As the adhesive, conventionally known adhesives can be used, and those having an aqueous polyurethane resin dispersion are preferred since they have a particularly high affinity with a nonporous film and less VOC discharge.

As a method for bonding the nonporous film and the fiber fabric, a conventionally known method can be used. For example, a wet laminating method or a dry laminating method in which the nonporous film and the fiber fabric are bonded using an adhesive, The direct coating method etc. which apply | coat the said polyurethane resin aqueous dispersion (1) or (2) used for formation of a porous film directly on a fiber fabric etc. are mentioned.
Of these, the dry laminating method is preferred because it is more excellent in moisture permeability or water pressure resistance.

As a method for producing a moisture-permeable waterproof fabric by the dry laminating method, for example, an adhesive is applied to the nonporous film surface formed on the release sheet by a knife coater, comma coater, bar coater or gravure roll coater. Then, an adhesive layer (preferably the thickness of the layer is 5 to 50 μm) is formed by heating at 60 to 160 ° C. Subsequently, a fiber fabric is arrange | positioned on the adhesive bond layer, and a moisture-permeable waterproof fabric can be manufactured by bonding together with the nip roll of temperature 80-150 degreeC and pressure 0.1-1 MPa.
In addition, after bonding a nonporous film and a fiber fabric, you may perform a water repellent process using a water repellent.

Next, although an Example and a comparative example are shown and this invention is demonstrated further more concretely, this invention is not limited only to these Examples.
In the following description, unless otherwise specified, “parts” and “%” are solid contents excluding water, and mean mass parts and mass%, respectively.

  In this example, the free isocyanate group (f-NCO) content in the isocyanate group-terminated urethane prepolymer, the oxyethylene group content and carboxy group content in the polyurethane resin, and the particle diameter at 90% cumulative passage of the polyurethane resin aqueous dispersion The moisture permeability and water pressure resistance of the nonporous film and the moisture-permeable waterproof fabric were measured by the following methods.

[F-NCO]
The free isocyanate group (f-NCO) content in the isocyanate group-terminated urethane prepolymer was measured by a method based on JIS K 7301.

[Oxyethylene group content, carboxy group content]
The oxyethylene group content and the carboxy group content in the polyurethane resin were calculated from the content of the oxyethylene group in the component (B) and the content of the carboxy group in the component (E) with respect to the total amount of the raw materials charged. .

[Particle size at 90% cumulative passage]
The particle diameter at 90% cumulative passage of the aqueous polyurethane resin dispersion was measured at 20 ° C. using Microtrac (trade name: UPA150, manufactured by Nikkiso Co., Ltd.).

[Moisture permeability]
The moisture permeability measured according to JIS L 1099 B-1 method (potassium acetate method) was displayed in terms of 24 hours (g / (m ² · 24 hours)).

[Water pressure resistance]
The water resistance was measured according to JIS L 1092 (water resistance test (hydrostatic pressure method) B method (high water pressure method)). In order to suppress the elongation of the test piece during water resistance measurement, a nylon taffeta (warp yarn: 70 decitex / 68 filament, warp yarn: 70 decitex / 68 filament, density: 120 warp / 2.54 cm, Measurement was performed in a state in which 90 horizontal / 2.54 cm) piled up.

<Evaluation of moisture permeability and water pressure resistance>
The moisture permeability and the water pressure resistance were evaluated by measuring the moisture permeability and the water pressure resistance of the non-porous film and the moisture permeable waterproof fabric prepared by using the polyurethane resin aqueous dispersion obtained in the production examples described later.

<Evaluation of washing resistance>
The moisture-permeable waterproof fabric was subjected to a washing test according to No. 103 in JIS L 0217 Attached Table 1 10 times, and the moisture permeability and the water pressure resistance before and after 10 washing tests and 10 Washing resistance was evaluated by measuring the appearance of the porous film and the presence or absence (visual observation) of peeling of the nonporous film from the fiber fabric.
The appearance of the nonporous film was evaluated based on the following criteria.
○: Neither expansion nor whitening was observed on the nonporous film surface.
X: One or both of expansion and whitening were observed on the surface of the nonporous film.

<Production example of aqueous polyurethane resin dispersion>
(Examples 1-9, Comparative Examples 1-8)
The aqueous polyurethane resin dispersion of each example was produced by the following production examples using the following raw materials.

(A) Polytetramethylene ether glycol (A-1) Polytetramethylene ether glycol (number average molecular weight: 1000).
(A-2) Polytetramethylene ether glycol (number average molecular weight: 2000).
(B) Polyol having an oxyethylene group (B-1) Polyethylene glycol (content of oxyethylene group 100% by mass, number average molecular weight: 1000).
(B-2) Polyethylene glycol (oxyethylene group content: 100% by mass, number average molecular weight: 2000).
(B-3) Polyethylene glycol (oxyethylene group content: 100% by mass, number average molecular weight: 5000).
(C) Alkylenediol having a branched alkylene group (C-1) 2,2-dimethylpropanediol.
(C-2) 3-methyl-1,5-pentanediol.
(D) Organic polyisocyanate (D-1) Dicyclohexylmethane diisocyanate.
(D-2) Isophorone diisocyanate.
(E) Polyol having a carboxy group (E-1) Dimethylolpropionic acid.
(E-2) Dimethylol butanoic acid.
(F) Chain extender (F-1) Isophorone diamine.
(F-2) Dipropylene triamine.

Methyl ethyl ketone was used as the organic solvent.
As a comparative component of the component (C), 1,6-hexanediol was used.
As another component, triethylamine which is a tertiary amine compound was used.

Example 1
Example of production of aqueous polyurethane resin dispersion 1:
In a four-necked flask equipped with a stirrer, reflux condenser, thermometer and nitrogen blowing tube, 39.39 parts by mass of polytetramethylene ether glycol (number average molecular weight: 1000) and polyethylene glycol (number average molecular weight: 1000) By adding 20.23 parts by mass, 4.72 parts by mass of 2,2-dimethylpropanediol, 31.97 parts by mass of dicyclohexylmethane diisocyanate, and 90 parts by mass of methyl ethyl ketone, and reacting at 75 ° C. for 3 hours, A methyl ethyl ketone solution of an isocyanate group-terminated urethane prepolymer having a free isocyanate group content of 1.90% by mass was obtained.
The methyl ethyl ketone solution was cooled to 40 ° C., and 400 parts by mass of water was gradually added and emulsified and dispersed while stirring with a homogenizer.
Then, what melt | dissolved 3.69 mass parts isophoronediamine in 30 mass parts water was added to this emulsified dispersion (prepolymer dispersion liquid), and it stirred for 1 hour.
Next, by depressurizingly distilling off methyl ethyl ketone at 50 ° C. under reduced pressure, a polyurethane resin having an oxyethylene group content of 21% by mass dispersed in water, a polyurethane having a particle size of 290 nm at a solid content of 30% by mass and a passing cumulative of 90%. An aqueous resin dispersion 1 was obtained.

(Examples 2 and 3)
Polyurethane resin aqueous dispersions 2 and 3 were obtained in the same manner as in Example 1 except that the raw materials listed in Table 1 were used.

Example 4
Example of production of aqueous polyurethane resin dispersion 4:
In a four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen blowing tube, 38.91 parts by mass of polytetramethylene ether glycol (number average molecular weight: 1000) and polyethylene glycol (average molecular weight 1000) 20. 39 parts by mass, 4.51 parts by mass of 2,2-dimethylpropanediol, 0.29 parts by mass of dimethylolpropionic acid, 31.81 parts by mass of dicyclohexylmethane diisocyanate, and 90 parts by mass of methyl ethyl ketone were added. By reacting at 3 ° C. for 3 hours, a methyl ethyl ketone solution of an isocyanate group-terminated urethane prepolymer having a free isocyanate group content of 2.00% by mass was obtained.
This methyl ethyl ketone solution was cooled to 40 ° C., 0.22 parts by mass of triethylamine was added for neutralization, and then 400 parts by mass of water was gradually added and emulsified with stirring with a homogenizer.
Then, what melt | dissolved 3.87 mass parts isophoronediamine in 30 mass parts water was added to this emulsified dispersion (prepolymer dispersion liquid), and it stirred for 1 hour.
Subsequently, methyl ethyl ketone was distilled off under reduced pressure at 50 ° C. under reduced pressure, whereby a polyurethane resin having an oxyethylene group content of 21% by mass and a carboxy group content of 0.10% by mass was dispersed in water. A polyurethane resin aqueous dispersion 4 having a particle diameter of 100 nm at an accumulation of 90% was obtained.

(Examples 5 to 9)
Polyurethane resin aqueous dispersions 5 to 9 were obtained in the same manner as in Example 4 except that the raw materials shown in Table 1 were used.

(Comparative Examples 1-3)
Polyurethane resin aqueous dispersions 10 to 12 were obtained in the same manner as in Example 1 except that the raw materials listed in Table 2 were used.

(Comparative Examples 4 to 8)
Polyurethane resin aqueous dispersions 13 to 17 were obtained in the same manner as in Example 4 except that the raw materials listed in Table 2 were used.

<Preparation of nonporous film>
On the release paper, the obtained polyurethane resin aqueous dispersions 1 to 17 were applied with a comma coater so that the film thickness after heating was 20 μm, heated at 80 ° C. for 1 minute, and subsequently at 130 ° C. Nonporous films were produced by heating for a minute.
As the release paper, EV130TPD (manufactured by Lintec Corporation) was used.

About the polyurethane resin aqueous dispersion of each example, the content of f-NCO in the isocyanate group-terminated urethane prepolymer prepared during the production, the oxyethylene group content and the carboxy group in the polyurethane resin contained in the aqueous dispersion Tables 1 and 2 also list the content, the solid content of the aqueous dispersion, and the particle diameter at 90% cumulative accumulation of the aqueous dispersion.
Moreover, the result of said <evaluation of moisture permeability and water pressure resistance> performed about the nonporous film of each case was written together in Table 1,2.

  As is apparent from Tables 1 and 2, the nonporous film formed by heating the aqueous polyurethane resin dispersions of Examples 1 to 9 according to the present invention has excellent moisture permeability and water pressure resistance. I understand that.

On the other hand, as in Comparative Examples 1 and 4, the polyurethane resin aqueous dispersion not using the component (C) in the present invention has a particle diameter at a passing accumulation of 90% larger than 500 nm. When it uses, it turns out that the water pressure resistance of the nonporous film obtained worsens.
Further, as in Comparative Examples 2 and 5, when using an aqueous dispersion containing a polyurethane resin having an oxyethylene group content of less than 20% by mass, the moisture permeability of the obtained nonporous film is deteriorated, As in Comparative Examples 3 and 6, when an aqueous dispersion containing a polyurethane resin having an oxyethylene group content exceeding 30% by mass is used, it is understood that the water pressure resistance of the nonporous film is deteriorated.
Further, as in Comparative Example 7, a linear alkylene diol different from the component (C) in the present invention was used, and an aqueous dispersion containing a polyurethane resin having a carboxy group content exceeding 1.0% by mass was used. In this case, it can be seen that the water resistance of the obtained nonporous film is deteriorated.
As in Comparative Example 8, when an aqueous dispersion containing a polyurethane resin having a carboxy group content exceeding 1.0% by mass is used, both the moisture permeability and water pressure resistance of the nonporous film may be deteriorated. I understand.

<Production example of moisture-permeable waterproof fabric>
(Examples 11-20, Comparative Examples 11-18)
The moisture-permeable waterproof fabric of each example was manufactured by the following manufacturing methods using the following materials.

Fiber fabric 1:
Nylon taffeta (warp yarn: 83 decites / 72 filament, weft yarn: 83 decites / 72 filament, density: warp 114 / 2.54 cm, width 92 / 2.54 cm) dyed black with an acid dye.
Fiber fabric 2:
Polyester woven fabric (warp yarn: 83 decites / 72 filaments, weft yarn: 83 decites / 72 filaments, density: 180 watts / inch, 94 pcs / inch weave).

Release paper:
EV130TPD (manufactured by Lintec Corporation) was used.

adhesive:
100 mass parts of polyurethane resin aqueous dispersion-containing adhesive (trade name: F-2099D-B2, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 10 mass of carbodiimide-based crosslinking agent (trade name: Carbodilite V02-L2, manufactured by Nisshinbo Chemical Co., Ltd.) And 3 parts by mass of a thickener (trade name: M-2005A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) were used.

(Example 11)
On the release paper, the aqueous polyurethane resin dispersion 1 obtained in Example 1 was applied with a comma coater so that the film thickness after heating was 20 μm, heated at 80 ° C. for 1 minute, and subsequently at 130 ° C. Was heated for 1 minute to obtain a nonporous film 1.
Subsequently, an adhesive was applied to the obtained nonporous film 1 with a comma coater so that the film thickness after heating was 15 μm, and the adhesive layer was formed by heating at 100 ° C. for 2 minutes.
Next, the fiber fabric 1 is disposed on the adhesive layer, and supplied to a pair of nip rolls (temperature 120 ° C., pressure 0.15 MPa) to bond the nonporous film 1 and the fiber fabric 1 together, and further 70 Cured for 24 hours at ℃.
Further, the release paper is peeled from the nonporous film 1 and the nonporous film 1 and the fiber fabric 1 are bonded to each other, and a fluorine-based water repellent aqueous solution (trade name: Asahi Guard AG710, Asahi Glass Co., Ltd.) The moisture-permeable waterproof fabric 1 was obtained by performing water-repellent treatment (padding, heating, heat treatment).

(Examples 12-20, Comparative Examples 11-18)
Moisture permeable waterproof fabrics 2 to 18 were obtained in the same manner as in Example 11 except that the materials shown in Table 3 (polyurethane resin aqueous dispersion, fiber fabric) were used.

  The results of the above <Evaluation of moisture permeability and water pressure resistance> and <Evaluation of washing resistance> performed on the moisture permeable waterproof fabric of each example are shown in Tables 3 and 4 together.

  As is apparent from Tables 3 and 4, the moisture-permeable waterproof fabrics of Examples 11 to 20 according to the present invention have excellent moisture permeability, water pressure resistance and washing resistance.

On the other hand, as in Comparative Examples 11 and 14, it was confirmed that the moisture-permeable waterproof fabric using the polyurethane resin aqueous dispersion having a particle diameter at 90% of accumulated passage larger than 500 nm has poor water pressure resistance.
Further, as in Comparative Examples 12 and 15, the moisture-permeable waterproof fabric using the aqueous dispersion containing the polyurethane resin having an oxyethylene group content of less than 20% by mass has poor moisture permeability. As described above, the moisture-permeable waterproof fabric using an aqueous dispersion containing a polyurethane resin having an oxyethylene group content of more than 30% by mass is poor in water pressure resistance and has a poor appearance of a nonporous film and a fiber fabric after a washing test. It was confirmed that peeling occurred.
Further, as in Comparative Example 17, a linear alkylene diol different from the component (C) in the present invention was used, and an aqueous dispersion containing a polyurethane resin having a carboxy group content exceeding 1.0% by mass was used. It was confirmed that the moisture-permeable waterproof fabric causes poor appearance of the nonporous film after the washing test.
As in Comparative Example 18, the moisture-permeable waterproof fabric using an aqueous dispersion containing a polyurethane resin having a carboxy group content exceeding 1.0% by mass has poor water pressure resistance and is a non-porous film fiber after a washing test. It was confirmed that peeling from the fabric occurred.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention. The present invention is not limited by the above description, but only by the scope of the appended claims.

  The moisture-permeable waterproof fabric of the present invention is excellent in all of moisture permeability, water pressure resistance, and washing resistance. Therefore, for example, clothing such as ski wear and golf wear, tents, sleeping bags, and other moisture permeability and waterproof properties are required. Can be used for things.

Claims (5)

Isocyanate group-terminated urethane produced by reaction of polytetramethylene ether glycol (A), polyol (B) having an oxyethylene group, alkylene diol (C) having a branched alkylene group, and organic polyisocyanate (D) A polyurethane resin aqueous dispersion used for a non-porous film of a moisture-permeable waterproof fabric in which a polyurethane resin obtained by chain extension reaction of a prepolymer with a chain extender (F) is dispersed in water,
The alkylene diol (C) having a branched alkylene group is 2,2-dimethylpropanediol, 3-methyl-1,5-pentanediol, 1,2-propylene glycol, 2-methyl-1,3-propanediol, At least one selected from the group consisting of 2,3-butanediol, 3-methyl-1,3-butanediol, 2-methyl-1,8-octanediol,
The particle diameter at 90% of accumulated passage is 500 nm or less,
An aqueous polyurethane resin dispersion in which the polyurethane resin has an oxyethylene group content of 20 to 30% by mass and does not contain a carboxy group with respect to the polyurethane resin. Polytetramethylene ether glycol (A), polyol (B) having an oxyethylene group, alkylene diol (C) having a branched alkylene group, organic polyisocyanate (D), polyol (E) having a carboxy group, Polyurethane resin aqueous dispersion for use in non-porous film of moisture permeable waterproof fabric in which polyurethane resin obtained by reacting chain reaction with chain extender (F) is produced by reacting isocyanate group-terminated urethane prepolymer with water Because
The alkylene diol (C) having a branched alkylene group is 2,2-dimethylpropanediol, 3-methyl-1,5-pentanediol, 1,2-propylene glycol, 2-methyl-1,3-propanediol, At least one selected from the group consisting of 2,3-butanediol, 3-methyl-1,3-butanediol, 2-methyl-1,8-octanediol,
The particle diameter at 90% of accumulated passage is 500 nm or less,
The polyurethane resin has an oxyethylene group content of 20 to 30% by mass with respect to the polyurethane resin and a carboxy group content of 1.0% by mass or less with respect to the polyurethane resin. Aqueous dispersion.
  A nonporous film formed by heating the aqueous polyurethane resin dispersion according to claim 1.   A moisture-permeable waterproof fabric comprising the nonporous film according to claim 3 and a fiber fabric. A method for producing the moisture-permeable waterproof fabric according to claim 4,
Forming a nonporous film by applying and heating the polyurethane resin aqueous dispersion on at least one side of a release sheet; and
Applying an adhesive to at least one surface of the nonporous film and the fiber fabric;
A method for producing a moisture-permeable waterproof fabric, comprising the step of bonding the nonporous film and the fiber fabric via the adhesive.