JP7322271B1 - Polyurethane resin, moisture-permeable film, and moisture-permeable waterproof fabric - Google Patents

Abstract

[PROBLEMS] To provide a polyurethane resin which is excellent in moisture permeability and which can be used to produce a moisture-permeable film excellent in washing resistance, alcohol resistance, suitability for repeated coating, heat resistance, light resistance, and flexibility. do. The polyurethane resin is a reaction product of (i) a polyol component, (ii) a chain extender, and (iii) a polyisocyanate component. (i) the polyol component contains (i-1) polyethylene glycol and (i-2) a polyether polyol, and (ii) the chain extender contains (ii-1) a linear chain having 2 to 4 carbon atoms (iii) the polyisocyanate component contains (iii-1) an aromatic diisocyanate and (iii-2) an aliphatic diisocyanate, and satisfies the following requirements (1) and the like. Requirement (1): (ii) the chain extender further contains (ii-3) a triol. [Selection figure] None

Description

TECHNICAL FIELD The present invention relates to a polyurethane resin, a moisture-permeable film, and a moisture-permeable waterproof fabric.

Conventionally, as a moisture-permeable material for constructing a fabric exhibiting moisture permeability and waterproofness (hereinafter also referred to as "moisture-permeable waterproof fabric"), a microporous film made of fluororesin or polyurethane resin, or a hydrophilic resin A nonporous film or the like is used. In the case of a microporous film, it may become clogged with sweat, dirt, etc., and the moisture permeability tends to decrease. On the other hand, in the case of a nonporous film made of a hydrophilic resin, clogging does not reduce the moisture permeability. As the hydrophilic resin constituting the nonporous film, for example, a polyurethane resin containing a hydrophilic segment is used.

A moisture-permeable waterproof fabric has, for example, a three-layer structure in which a moisture-permeable skin layer, an adhesive layer, and a base fabric (fabric) are laminated. A non-porous, moisture-permeable film made of a hydrophilic polyurethane resin is used as a material for forming the skin layer. As a related prior art, for example, a hydrophilic polyurethane resin for a moisture-permeable waterproof fabric, which is obtained by reacting a hydrophilic polyol such as polyethylene glycol, a chain extender such as ethylene glycol, and an organic isocyanate, has been proposed. (Patent Documents 1 and 2).

A moisture-permeable film that constitutes a moisture-permeable waterproof fabric is required to have not only moisture permeability but also washing resistance, alcohol resistance, light resistance, and flexibility. When manufacturing a moisture-permeable waterproof fabric having a three-layer structure as described above, the adhesive layer is usually formed using a solvent-based or moisture-curing adhesive. For this reason, the moisture-permeable film is also required to have a property that it is difficult to shrink even when an adhesive is applied (so-called recoating suitability), and to have an appropriate heat resistance that is difficult to soften even when heated during adhesion.

Japanese Patent Application Laid-Open No. 2003-201675 JP-A-10-17764

However, the moisture-permeable films formed using the conventional hydrophilic polyurethane resins proposed in Patent Documents 1 and 2 exhibit moisture permeability to a certain extent, but they have resistance to washing, resistance to alcohol, suitability for overcoating, The heat resistance, light resistance, and flexibility were not necessarily sufficient, and there was room for further improvement.

The present invention has been made in view of the problems of the prior art. To provide a polyurethane resin capable of producing a moisture-permeable film having excellent properties, light resistance and flexibility.

In addition, the object of the present invention is to obtain using this polyurethane resin, which has excellent moisture permeability, washing resistance, alcohol resistance, suitability for overcoating, heat resistance, light resistance, and flexibility. To provide a moisture-permeable film excellent in moisture permeability and a moisture-permeable waterproof fabric provided with the moisture-permeable film.

That is, according to the present invention, the following polyurethane resin is provided.
[1] A polyurethane resin that is a reaction product of (i) a polyol component, (ii) a chain extender, and (iii) a polyisocyanate component, wherein the (i) polyol component is (i-1) polyethylene glycol , and (i-2) a polyether polyol other than the (i-1) polyethylene glycol, and the (ii) chain extender comprises (ii-1) a linear alkanediol having 2 to 4 carbon atoms. or (ii-2) other than (ii-1) linear alkanediol having 2 to 4 carbon atoms and (ii-1) linear alkanediol having 2 to 4 carbon atoms. A linear, branched, or cyclic alkanediol, and the (iii) polyisocyanate component includes (iii-1) an aromatic diisocyanate and (iii-2) an aliphatic diisocyanate, and the following requirements A polyurethane resin that satisfies at least one of (1) and (2).
Requirement (1): The (ii) chain extender further contains (ii-3) a triol.
Requirement (2): The (iii) polyisocyanate component further contains (iii-3) a polyfunctional isocyanate having a functionality of 3 or more.
[2] The polyurethane resin according to the above [1], wherein the amount of the (i-2) polyether polyol in the (i) polyol component is 30 to 70% by mass.
[3] The polyurethane resin according to [1] or [2] above, wherein the (ii-3) triol is trimethylolpropane.
[4] The amount of the (ii-3) triol with respect to 100 parts by mass of the (i) polyol component is 0.06 to 0.5 parts by mass. Polyurethane resin.
[5] Any one of the above [1] to [4], wherein the amount of the (iii-3) polyfunctional isocyanate relative to the (iii-1) aromatic diisocyanate is 0.1 to 0.65 mol%. of polyurethane resin.
[6] Any one of the above [1] to [5], wherein at least one of the (i) polyol component, the (ii) chain extender, and the (iii) polyisocyanate component is a plant-derived compound Polyurethane resin as described.
[7] The polyurethane resin according to any one of [1] to [6], which is used as a constituent material of a moisture-permeable film.

Moreover, according to this invention, the moisture-permeable film shown below is provided.
[8] A moisture-permeable film formed of the polyurethane resin described in [7] above.

Furthermore, according to the present invention, the following moisture-permeable waterproof fabric is provided.
[9] A moisture-permeable waterproof fabric comprising a base fabric and a skin layer provided on the surface of the base fabric, wherein the skin layer is the moisture-permeable film according to [8] above.
[10] The moisture-permeable waterproof fabric according to [9], further comprising an adhesive layer provided between the base fabric and the skin layer.
[11] The moisture-permeable waterproof fabric according to [9] or [10], further comprising a porous layer provided between the base fabric and the skin layer.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to produce a moisture-permeable film having excellent moisture permeability, washing resistance, alcohol resistance, suitability for repeated coating, heat resistance, light resistance, and flexibility. Resin can be provided.

In addition, according to the present invention, the polyurethane resin obtained using this polyurethane resin has excellent moisture permeability, as well as excellent washing resistance, alcohol resistance, suitability for overcoating, heat resistance, light resistance, and flexibility. A moisture-permeable film and a moisture-permeable waterproof fabric provided with this moisture-permeable film can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one Embodiment of the moisture-permeable waterproof fabric of this invention. Fig. 3 is a cross-sectional view schematically showing another embodiment of the moisture-permeable waterproof fabric of the present invention. FIG. 3 is a schematic diagram illustrating the form of a sample used in the evaluation of Examples. It is a schematic diagram explaining the form of the gear oven used by the evaluation of an Example.

<Polyurethane resin>
Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. One embodiment of the polyurethane resin of the present invention is a reaction product of (i) a polyol component, (ii) a chain extender, and (iii) a polyisocyanate component, and is suitable as a material for producing a moisture-permeable film, etc. Polyurethane resin. Details of the polyurethane resin of the present invention are described below.

((i) polyol component)
The (i) polyol component includes (i-1) polyethylene glycol and (i-2) polyether polyol other than (i-1) polyethylene glycol. It is preferable that the (i) polyol component is substantially composed only of (i-1) polyethylene glycol and (i-2) polyether polyol.

[(i-1) polyethylene glycol]
(i-1) Polyethylene glycol is a hydrophilic polyol that can contribute to the moisture permeability of the formed film. (i-1) The number average molecular weight (Mn) of polyethylene glycol is preferably 600 to 10,000, more preferably 1,000 to 7,000.

[(i-2) polyether polyol]
(i-2) Polyether polyol is a component that improves the mechanical properties of the formed film. (i-2) The number average molecular weight (Mn) of the polyether polyol is preferably 650 to 3,000, more preferably 1,000 to 2,500.

Examples of (i-2) polyether polyols include polypropylene glycol, polyethylene glycol-polytetramethylene glycol (block or random), polytrimethylene ether glycol, polytetramethylene ether glycol, and polyhexamethylene ether glycol. can. Among them, polytrimethylene ether glycol and polytetramethylene ether glycol are preferable from the viewpoint of flexibility and the like.

(i-2) Polyether polyol can be obtained, for example, by polymerizing or copolymerizing either an alkylene oxide (propylene oxide, butylene oxide, etc.) or a heterocyclic ether (tetrahydrofuran, 2-methyltetrahydrofuran, etc.). . The (i-2) polyether polyol can also be obtained by a dehydration condensation reaction of a diol such as 1,3-propanediol.

(i-2) polyether polyol is preferably a plant-derived compound from the viewpoint of making the resin or film environmentally friendly. Examples of (i-2) polyether polyols, which are plant-derived compounds, include polyether polyols made from plant-derived diols, tetrahydrofuran, and the like.

In the (i) polyol component (total of (i-1) polyethylene glycol and (i-2) polyether polyol), the amount of (i-2) polyether polyol (hydrophobic polyol) is 30 to 70% by mass. preferably 35 to 60% by mass. By setting the amount of (i-2) polyether polyol in the polyol component (i) within the above range, it is possible to obtain a polyurethane resin capable of producing a moisture-permeable film having an excellent balance between moisture permeability and flexibility. can.

((ii) chain extender)
(ii) the chain extender contains (ii-1) two or more straight-chain alkanediols having 2 to 4 carbon atoms, or (ii-1) a straight-chain alkanediol having 2 to 4 carbon atoms, and (ii-2) linear, branched or cyclic alkanediols other than (ii-1) linear alkanediols having 2 to 4 carbon atoms. That is, by using a combination of two or more types of alkanediols having different alkylene carbon numbers, etc. as (ii) a chain extender, compared to the case where only one type of alkanediol is used as a chain extender, solvent-based It is possible to obtain a polyurethane resin that can produce a moisture-permeable film with improved so-called recoating suitability, which is resistant to shrinkage even when the adhesive is applied. The reason why such an effect is obtained is not necessarily clear, but by using a combination of two or more types of alkanediols having different alkylene carbon numbers, etc., moderate "play" occurs in the molecular chain of the polyurethane resin, It is presumed that this is because the crystallinity was slightly lowered.

(ii) The amount of the chain extender is preferably 0.2 to 40% by mass, preferably 0.5 to 20% by mass, based on the total of (i) the polyol component and (ii) the chain extender. is more preferable, and 12 to 16% by mass is particularly preferable. Note that (ii) the chain extender preferably does not substantially contain an amine compound. When an amine compound is used as a chain extender, the obtained moisture-permeable film tends to have lower heat resistance.

[(ii-1) linear alkanediol having 2 to 4 carbon atoms]
(ii-1) Linear alkanediols having 2 to 4 carbon atoms include ethylene glycol, 1,3-propanediol, and 1,4-butanediol. From the viewpoint of environmentally friendly resins and films, the (ii-1) linear alkanediol having 2 to 4 carbon atoms may be a plant-derived compound. Examples of plant-derived compounds (ii-1) linear alkanediols having 2 to 4 carbon atoms include plant-derived ethylene glycol, 1,3-propanediol, and 1,4-butanediol. can be mentioned. A plant-derived linear alkanediol and a petroleum-derived linear alkanediol can also be combined.

[(ii-2) linear, branched, or cyclic alkanediol]
As the straight-chain alkanediol, a straight-chain alkanediol having 5 or more carbon atoms can be used. Linear alkanediols having 5 or more carbon atoms include 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1, 10-decanediol, 1,12-dodecanediol and the like can be mentioned.

As the branched alkanediol, a branched alkanediol having 3 or more carbon atoms can be used. Branched alkanediols having 3 or more carbon atoms include 1,3-butanediol, 3-methyl-1,5-pentanediol (MPD), neopentyl glycol (NPD), 2-methylpropanediol, 2,2- dimethylpropanediol, 2-propyl-1,4-butanediol, 2-isopropyl-1,4-butanediol, 2-cyclopropyl-1,4-butanediol, 2,2,4,4-tetramethyl-1 ,3-cyclobutanediol 2-butyl-1,4-butanediol, 2-isobutyl-1,4-butanediol, 2-methyl-1,3-pentanediol, 2,2,4-trimethyl-1,3- Pentanediol 2-propyl-1,5-pentanediol, 2-isopropyl-1,5-pentanediol, 2-cyclopropyl-1,5-pentanediol, 2-butyl-1,5-pentanediol, 2-propyl -1,6-hexanediol, 2-isopropyl-1,6-hexanediol, 2-cyclopropyl-1,6-hexanediol, 2-butyl-1,6-hexanediol, 2-propyl-1,7- Heptanediol, 2-isopropyl-1,7-heptanediol, 2-cyclopropyl-1,7-heptanediol, 2-butyl-1,7-heptanediol, 2-methyl-1,8-octanediol, 2- Propyl-1,8-octanediol, 2-isopropyl-1,8-octanediol, 2-cyclopropyl-1,8-octanediol, 2-butyl-1,8-octanediol, 2-propyl-1,9 -nonanediol, 2-isopropyl-1,9-nonanediol, 2-cyclopropyl-1,9-nonanediol, 2-butyl-1,9-nonanediol, 2-cyclobutyl-1,9-nonanediol, 2 -propyl-1,10-decanediol, 2-isopropyl-1,10-decanediol, 2-cyclopropyl-1,10-decanediol, 2-butyl-1,10-decanediol, 2-propyl-1, 11-undecanediol, 2-isopropyl-1,11-undecanediol, 2-cyclopropyl-1,11-undecanediol, 2-butyl-1,11-undecanediol, 2-dodecyl-1,11-undecanediol, 2-propyl-1,12-dodecanediol, 2-isopropyl-1,12-dodecanediol, 2-cyclopropyl-1,12-dodecanediol, 2-butyl-1,12-dodecanediol and the like. can.

Examples of cyclic alkanediols include 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and 2,2′-bis(4-hydroxycyclohexyl)propane. .

((iii) polyisocyanate component)
(iii) The polyisocyanate component is a compound having two or more isocyanate groups (NCO groups) in one molecule, and includes (iii-1) aromatic diisocyanate and (iii-2) aliphatic diisocyanate.

[(iii-1) aromatic diisocyanate]
(iii-1) Aromatic diisocyanates include 4,4′-diphenylmethane diisocyanate (MDI), 2,2′-MDI, 2,4′-MDI, 2,4-tolylene diisocyanate (TDI), 2,6 -TDI, m-xylylene diisocyanate (XDI), 1,4-phenylene diisocyanate, 4-methoxy-1,3-phenylene diisocyanate, 4-isopropyl-1,3-phenylene diisocyanate, 4-butoxy-1,3-phenylene Diisocyanate, 2,4-diisocyanate diphenyl ether, 1,5-naphthalene diisocyanate, benzidine diisocyanate and the like can be mentioned. Among these, MDI is preferred.

[(iii-2) aliphatic diisocyanate]
(iii-2) Aliphatic diisocyanates include 1,4-tetramethylene diisocyanate, 1,5-pentane diisocyanate (PDI), 1,6-hexamethylene diisocyanate (HDI), and 1,10-decamethylene diisocyanate. Aliphatic diisocyanates; 4,4′-methylenebis(cyclohexyl isocyanate), isophorone diisocyanate (IPDI), 1,3-bis(isocyanatomethyl)cyclohexane (hydrogenated XDI), dicyclohexylmethane-4,4′-diisocyanate (hydrogenated MDI), and alicyclic diisocyanates such as 1-methylcyclohexane-2,4-diisocyanate (hydrogenated TDI); Among these, HDI and plant-derived PDI are preferred.

The mass ratio of (iii-1) aromatic diisocyanate and (iii-2) aliphatic diisocyanate is preferably (iii-1):(iii-2) = 30:70 to 85:15, and 60 :40 to 80:20 is more preferable. (iii-1) If the amount of the aromatic diisocyanate is too large, the formed moisture-permeable film tends to be hard. On the other hand, if the amount of (iii-2) aliphatic diisocyanate is too large, the formed moisture-permeable film tends to be soft. Further, the amount of (iii-2) aliphatic diisocyanate is preferably 10 to 85 mol%, more preferably 20 to 60 mol%, more preferably 30 to 40 mol, based on the total amount of (iii) polyisocyanate component. % is particularly preferred.

At least one of (i) the polyol component, (ii) the chain extender, and (iii) the polyisocyanate component is preferably a plant-derived compound from the viewpoint of making the resin or film environmentally friendly.

(Requirements (1) and (2))
The polyurethane resin of this embodiment satisfies at least one of the following requirements (1) and (2).
Requirement (1): (ii) the chain extender further contains (ii-3) a triol.
Requirement (2): (iii) the polyisocyanate component further contains (iii-3) a polyfunctional isocyanate having a functionality of 3 or more.

Simply increasing the amount of hard segments in the raw material polyurethane resin in order to improve properties such as alcohol resistance and heat resistance of the moisture-permeable film tends to impair the flexibility (texture, etc.) of the moisture-permeable film. On the other hand, at least one of the above requirements (1) and (2) is satisfied, that is, (ii-3) triol and (iii-3) polyfunctional isocyanate. The polyurethane resin of the embodiment is a branched polymer (thermoplastic resin) having an internal crosslinked structure. With such an internal crosslinked structure, the polyurethane resin of the present embodiment can produce a moisture-permeable film with improved properties such as washing resistance, alcohol resistance, and heat resistance while maintaining flexibility. can be done. On the other hand, when a trifunctional or higher compound such as (ii-3) triol or (iii-3) polyfunctional isocyanate is reacted after synthesizing the polyurethane resin, it tends to become a thermosetting resin having a so-called network structure. Softness (texture) may be inferior.

[(ii-3) triol]
(ii-3) Triol is a trifunctional polyol having three hydroxyl groups (OH groups) in one molecule. (ii-3) The molecular weight (chemical formula weight) of triol is preferably 500 or less, more preferably 300 or less. (ii-3) Triols include glycerin, trimethylolethane, trimethylolpropane, butanetriol, pentanetriol, hexanetriol, heptanetriol, and octanetriol. Among these, glycerin and trimethylolpropane are preferred, and trimethylolpropane is more preferred.

When the polyurethane resin of the present embodiment satisfies requirement (1), the amount of (ii-3) triol is preferably 0.06 to 0.5 parts by mass with respect to 100 parts by mass of (i) polyol component. , more preferably 0.1 to 0.45 parts by mass. By adjusting the amount of (ii-3) triol to 100 parts by mass of the polyol component (i) within the above range, a polyurethane that can produce a moisture-permeable film with further improved washing resistance, alcohol resistance, and heat resistance. It can be made of resin.

[(iii-3) polyfunctional isocyanate]
(iii-3) The polyfunctional isocyanate is a trifunctional or higher polyfunctional isocyanate having 3 or more isocyanate groups (NCO groups) in one molecule. (iii-3) Polyfunctional isocyanates include diphenylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, and isophorone diisocyanate; trimethylolpropane adducts, biurets, and nurates thereof; polymeric MDI a terminal isocyanate prepolymer; and the like. Polyisocyanates in the form of these blocks can also be used. Among these, adducts, biurets, and nurates of aliphatic diisocyanates such as hexamethylene diisocyanate and pentamethylene diisocyanate are preferred.

When the polyurethane resin of the present embodiment satisfies requirement (2), the amount of (iii-3) polyfunctional isocyanate relative to (iii-1) aromatic diisocyanate is 0.1 to 0.65 mol%. It is preferably 0.2 to 0.5 mol %, and more preferably 0.2 to 0.5 mol %. By setting the amount of (iii-3) polyfunctional isocyanate to (iii-1) aromatic diisocyanate within the above range, a moisture-permeable film with further improved washing resistance, alcohol resistance, and heat resistance is manufactured. Polyurethane resin can be used.

(Method for producing polyurethane resin)
Polyurethane resins are produced by, for example, (i) a polyol component, (ii) a chain extender, and (iii) a polyisocyanate component by a one-shot method or a multistage method, preferably at 60 to 150°C, more preferably 60 to 110°C. can be produced by reacting with A catalyst may be used in combination during the reaction, if necessary. Examples of catalysts include metal salts and organometallic derivatives such as dibutyltin laurate, dioctyltin laurate, stannous octoate, lead octylate, and tetra-n-butyl titanate; organic amines such as triethylamine; and diazabicycloundecene-based catalysts. ; etc. can be mentioned.

The (i) polyol component, (ii) chain extender, and (iii) polyisocyanate component can be reacted in the presence of a solvent such as an organic solvent. By reacting in the presence of a solvent, it is possible to obtain a solution in which the polyurethane resin is dissolved in the solvent or a dispersion in which it is dispersed. Examples of solvents include organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dioxane, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, N-ethylpyrrolidone, β-alkoxypropionamide, dipropylene glycol dimethyl ether, and ethyl acetate. can be mentioned.

Polyurethane resin solutions or dispersions may optionally contain thermoplastic resins, tackifier resins, catalysts, pigments, antioxidants, UV absorbers, surfactants, flame retardants, fillers, blowing agents, and the like. Appropriate amounts of various additives may be added.

<Moisture-permeable film>
One embodiment of the moisture-permeable film of the present invention is a moisture-permeable and waterproof film formed of the polyurethane resin described above. That is, since the moisture-permeable film of the present embodiment is a film formed of the polyurethane resin described above, it has excellent moisture-permeability, as well as washing resistance, alcohol resistance, suitability for overcoating, heat resistance, and light resistance. , and flexibility. Therefore, the moisture-permeable film of the present embodiment is suitable as a material for constructing a moisture-permeable waterproof fabric.

A moisture-permeable film can be produced, for example, by applying a solution or dispersion of a polyurethane resin to a base material such as release paper, followed by drying to remove the solvent. Examples of the method (coating method) for applying a polyurethane resin solution or the like to a substrate include conventionally known coating methods such as a comma coating method, a knife coating method, a roll coating method, a gravure coating method, and a spray coating method. be able to.

The thickness of the moisture-permeable film may be appropriately set within a range in which moisture-permeability and waterproofness are exhibited, and may be, for example, within the range of 10 to 15 μm. The thickness of the moisture-permeable film can be appropriately set by changing the thickness of a coating film formed by coating a substrate with a polyurethane resin solution or the like.

The 100% modulus of the moisture-permeable film at 25° C. is usually 3.0-5.0 MPa, preferably 3.5-4.5 MPa. The 20% modulus of the moisture-permeable film at 25°C is usually 1.5-4.0 MPa, preferably 1.8-3.7 MPa. The moisture-permeable film of the present embodiment, in which the values of 100% modulus and 20% modulus are respectively within the above ranges, maintains properties such as washing resistance and flexibility (texture) in a better balance. .

<Moisture-permeable waterproof fabric>
FIG. 1 is a cross-sectional view schematically showing one embodiment of the moisture-permeable waterproof fabric of the present invention. As shown in FIG. 1 , the moisture-permeable waterproof fabric 100 of this embodiment includes a base fabric 2 and a skin layer 4 provided on the surface of the base fabric 2 . The skin layer 4 is the aforementioned moisture-permeable film made of a specific polyurethane resin. The moisture-permeable waterproof fabric 100 of the present embodiment uses a moisture-permeable and waterproof film that is excellent in washing resistance, alcohol resistance, recoating suitability, heat resistance, light resistance, and flexibility as the skin layer 4. It is. Therefore, the moisture-permeable waterproof fabric 100 of the present embodiment is excellent in moisture permeability and waterproofness, and is also excellent in washing resistance, alcohol resistance, heat resistance, light resistance, and flexibility.

FIG. 2 is a cross-sectional view schematically showing another embodiment of the moisture-permeable waterproof fabric of the present invention. The moisture-permeable waterproof fabric 200 of the embodiment shown in FIG. 2 further includes a porous layer 6 and an adhesive layer 8 provided between the base fabric 2 and the skin layer 4 . That is, the skin layer 4 may be fixed onto the base fabric 2 via the adhesive layer 8 or may be fixed onto the base fabric 2 via the porous layer 6 and the adhesive layer 8 .

The adhesive layer 8 can be formed of, for example, a two-component curable urethane-based adhesive or the like that is used when manufacturing conventional fabrics such as moisture-permeable and waterproof fabrics. Moreover, the porous layer 6 is the same layer as the porous layer constituting the conventional moisture-permeable waterproof fabric, and can be formed of, for example, urethane resin, acetylcellulose, epoxy resin, or the like.

As the base fabric 2, for example, a woven fabric made of twill weave, plain weave, etc., a raised cloth obtained by mechanically raising the cotton fabric of the woven fabric, a rayon cloth, a nylon cloth, a polyester cloth, a Kevlar cloth, a nonwoven fabric (polyester, nylon, various latexes), various films, sheets, and the like.

The moisture-permeable waterproof fabric can be produced, for example, by adhering the moisture-permeable film produced by the method described above onto a base fabric using an adhesive. In addition, in order to manufacture a moisture-permeable waterproof fabric 100 in which a moisture-permeable film as the skin layer 4 is directly provided on the base fabric 2 as shown in FIG. can be produced by coating to a desired thickness and then drying.

EXAMPLES The present invention will be specifically described below based on Examples, but the present invention is not limited to these Examples. "Parts" and "%" in Examples and Comparative Examples are based on mass unless otherwise specified.

<Production of polyurethane resin>
(Example 1)
In a glass reaction vessel equipped with a stirrer and a thermometer, 17.9 parts of polyethylene glycol 2000 (number average molecular weight: 2,000) and polytetramethylene were added as (i) a polyol component and (ii) a chain extender. 41.7 parts of glycol 2000 (number average molecular weight: 2,000), 3.6 parts of ethylene glycol, 5.2 parts of 1,4-butanediol, and 0.2 parts of trimethylolpropane were added. After that, 163.9 parts of dimethylformamide (DMF) and 70.2 parts of methyl ethyl ketone (MEK) were added and stirred at 50°C for 30 minutes. Next, 10.0 parts of hexamethylene diisocyanate and 21.9 parts of diphenylmethane diisocyanate were added as the (iii) polyisocyanate component and reacted at 80° C. for 3 hours to obtain a solution containing a polyurethane resin. The resulting solution had a solid content of 30.0% and a viscosity of 1,000 dPa·s at 25°C.

(Examples 2 to 28, Comparative Examples 1 to 9)
A solution containing a polyurethane resin was obtained in the same manner as in Example 1 described above, except that the formulations (unit: parts) shown in the upper rows of Tables 1-1 to 1-4 were used. The solid content of each of the obtained solutions was 30.0%. Details of the materials used are shown in Tables 2-4.

<Manufacture of moisture-permeable waterproof fabric>
(Standard fabric)
(1) Production of moisture-permeable film 100 parts of a solvent-based urethane resin (trade name “Heimulen Y-286FM”, manufactured by Dainichiseika Kogyo Co., Ltd.), 10 parts of DMF, and 5 parts of MEK are mixed to prepare a formulation for the skin layer. Obtained. Using a clearance coater, the obtained blended liquid for the skin layer was uniformly coated on release paper in a coating amount of 50 μm·wet. After drying at 80° C. for 2 minutes, it was further dried at 120° C. for 3 minutes to obtain a moisture-permeable film (skin layer) having a thickness of 10 to 15 μm.

(2) Adhesion between skin layer and base fabric Solvent-based urethane resin (trade name “Y-173”, manufactured by Dainichiseika Kogyo Co., Ltd.) 100 parts, solvent-based polyisocyanate cross-linking agent A (trade name “Rezamin NE-cross-linking agent” , Dainichiseika Kogyo Co., Ltd.) 10 parts, solvent-based polyisocyanate cross-linking agent B (trade name “Rezamin UD-crosslinking agent”, Dainichiseika Kogyo Co., Ltd.) 1 part, DMF 20 parts, and MEK 40 parts are mixed and bonded. A formulation for the layer was obtained. The obtained compounded solution for the adhesive layer was applied onto the skin layer (moisture-permeable film) and dried to form the adhesive layer. A base fabric (nylon taffeta) was laminated on the formed adhesive layer, and heated and press-bonded at a laminating temperature of 40°C. After that, it was aged at 50° C. for 48 hours to obtain a moisture-permeable and waterproof standard fabric.

(Fabric for evaluation)
A cloth for evaluation was obtained in the same manner as in the case of the above-described standard cloth, except that the solution containing the produced polyurethane resin was used in place of the blended liquid for the skin layer.

<Evaluation>
Among the evaluation criteria for each evaluation shown below, "⊚", "○", and "Δ" were regarded as pass, and "x" was regarded as unacceptable. Table 5 shows the evaluation results.

(texture)
The manufactured standard fabric and the fabric for evaluation were compared in terms of feel when touched with hands, and the feel (softness) was evaluated according to the evaluation criteria shown below.
A: The fabric for evaluation was softer than the standard fabric.
◯: The fabric for evaluation was as soft as the standard fabric.
x: The fabric for evaluation was harder than the standard fabric.

(Aptitude for overcoating)
When the skin layer and the base fabric were adhered, the state of the skin layer immediately after application of the adhesive layer formulation solution and after drying was visually observed, and the recoatability was evaluated according to the evaluation criteria shown below. In Comparative Example 4, since the skin layer (film) was dissolved immediately after the application of the formulation liquid for the adhesive layer, it was not possible to evaluate the suitability for repeated coating.
◯: No swelling was observed.
Δ: Slight swelling was observed.
x: There was swelling over the entire surface, or the epidermis layer was dissolved.

(Film properties)
Each of the prepared polyurethane resin solutions was applied to a release paper and then dried at 80° C. for 2 minutes and 120° C. for 3 minutes. After drying, it was peeled off from the release paper to obtain a translucent film having a thickness of 50 μm, a width of 1.5 cm and a length of 6 cm. Using an autograph (trade name "AGS-J", manufactured by Shimadzu Corporation), the obtained translucent film was pulled at a speed of 200 mm / min under conditions of a temperature of 25 ° C. and a humidity of 30% RH or less. Modulus (MPa) and 100% modulus (MPa) were measured respectively.

(Thermal softening point)
A translucent film (thickness: 50 µm, width: 1.5 cm, length: 6 cm) prepared according to the above-mentioned "film physical properties" was used as a test piece. As shown in FIG. 3, clips 12 were attached to the top and bottom of the film 10, and the clips 12 were further fixed with cellophane tape. A sample 16 was prepared by attaching a weight 14 such that a load of 450 g/cm ² is applied when suspended from one clip 12 . The central portion (2 cm) of the film 10 is not covered with cellophane tape. Next, as shown in FIG. 4, the clip 12 of the sample 16 without the weight 14 attached was attached to the rotating disk 22 of the gear oven 20 . After that, while rotating the turntable 22 at 5 rpm, the inside of the gear oven 20 was heated from room temperature at a rate of 3° C./min, and the temperature (thermal softening point (° C.)) when the film 10 was cut was measured.

(Alcohol resistance)
Each of the prepared polyurethane resin solutions was applied to a release paper and then dried at 80° C. for 2 minutes and 120° C. for 3 minutes. After drying, the film was peeled off from the release paper to obtain a film having a thickness of 50 µm, a width of 5 cm, and a length of 5 cm. The resulting film was immersed in ethanol for 10 minutes and then removed. The linear swelling rate of the removed film (= {(film width after immersion) / (film width before immersion)} x 100 (%)) was calculated, and the solvent resistance was evaluated according to the evaluation criteria shown below. bottom.
Good: The linear swelling rate of one side of the film was less than 200%.
Δ: The linear swelling rate of one side of the film was 200% or more.
x: The film was dissolved.

(light resistance)
Each solution of the produced polyurethane resin was applied on a release paper and dried at 80° C. for 2 minutes and 120° C. for 3 minutes. After drying, the film was peeled off from the release paper to obtain a film having a thickness of 50 µm, a width of 8 cm and a length of 15 cm. Using a xenon weatherometer, the obtained film was subjected to an accelerated light resistance test under the conditions of 70±3° C. and irradiation energy of 20 MJ. Using a tensile tester, the breaking strength of the film was measured before and after the accelerated light resistance test under the conditions of 25° C. and a tensile speed of 200 mm/min, and the light resistance was evaluated according to the evaluation criteria shown below.
○: The retention rate of breaking strength was 50% or more.
Δ: The retention rate of breaking strength was 25% or more and less than 50%.
x: The retention rate of breaking strength was less than 25%, or the film dissolved.

(moisture permeability)
The moisture permeability (g/m ² ·24 h) of the fabric for evaluation was measured by a method based on JIS L 1099:2012 "calcium acetate method (B-1 method)". In addition, when the moisture permeability was 40,000 g/m ² · 24 h or more, "○", 20,000 g / m ² · 24 h or more and less than 40,000 g / m ² · 24 h, "△", A case of less than 20,000 g/m ² ·24 h can be evaluated as "x". Incidentally, (ii) the film formed from the solution containing the polyurethane resin of Comparative Example 5, which was produced without using a chain extender, was extremely soft and was torn during the measurement, so the moisture permeability could not be measured. .

(wash resistance)
For the evaluation fabric, washing conforming to JIS L 1930: 2014 "C type standard washing machine (parasator type)" and drying conforming to "drying method C (flat drying)" were alternately repeated 20 times in total. . Then, by a method based on JIS L 1092: 2009 "B method (high water pressure method)", the water pressure resistance of the evaluation fabric before and after washing and drying is measured, and the washing resistance is evaluated according to the evaluation criteria shown below. bottom.
⊚: Retention rate of water pressure resistance was 80% or more.
◯: The retention rate of water pressure resistance was 70% or more and less than 80%.
x: Water pressure retention rate was less than 70%.

The polyurethane resin of the present invention is useful as a material for forming a moisture-permeable film that constitutes a moisture-permeable waterproof fabric or the like.

2: Base fabric 4: Skin layer 6: Porous layer 8: Adhesive layer 10: Film 12: Clip 14: Weight 16: Sample 20: Gear oven 22: Turntable 100, 200: Moisture-permeable waterproof fabric

Claims (11)

A polyurethane resin that is a reactant of (i) a polyol component, (ii) a chain extender, and (iii) a polyisocyanate component,
The (i) polyol component contains (i-1) polyethylene glycol and (i-2) a polyether polyol other than the (i-1) polyethylene glycol,
(ii) the chain extender contains (ii-1) two or more linear alkanediols having 2 to 4 carbon atoms, or
(ii-1) linear alkanediol having 2 to 4 carbon atoms, and (ii-2) linear, branched, other than (ii-1) linear alkanediol having 2 to 4 carbon atoms, or a cyclic alkanediol,
The (iii) polyisocyanate component contains (iii-1) an aromatic diisocyanate and (iii-2) an aliphatic diisocyanate,
(iii-1) the aromatic diisocyanate is 4,4′-diphenylmethane diisocyanate,
The mass ratio of the (iii-1) aromatic diisocyanate and the (iii-2) aliphatic diisocyanate is 30:70 to 85:15,
A polyurethane resin that satisfies at least one of the following requirements (1) and (2).
Requirement (1): The (ii) chain extender further contains (ii-3) a triol.
Requirement (2): The (iii) polyisocyanate component further contains (iii-3) a polyfunctional isocyanate having a functionality of 3 or more. 2. The polyurethane resin according to claim 1, wherein the amount of (i-2) polyether polyol in the (i) polyol component is 30 to 70% by mass. 2. The polyurethane resin according to claim 1, wherein (ii-3) triol is trimethylolpropane. 2. The polyurethane resin according to claim 1, wherein the amount of said (ii-3) triol is 0.06 to 0.5 parts by mass with respect to 100 parts by mass of said (i) polyol component. 2. The polyurethane resin according to claim 1, wherein the amount of (iii-3) polyfunctional isocyanate relative to (iii-1) aromatic diisocyanate is 0.1 to 0.65 mol %. 2. The polyurethane resin according to claim 1, wherein at least one of the (i) polyol component, the (ii) chain extender, and the (iii) polyisocyanate component is a plant-derived compound. The polyurethane resin according to any one of claims 1 to 6, which is used as a constituent material of a moisture-permeable film. A moisture-permeable film formed from the polyurethane resin according to claim 7 . A base fabric and a skin layer provided on the surface of the base fabric,
A moisture-permeable waterproof fabric, wherein the skin layer is the moisture-permeable film according to claim 8 . The moisture-permeable waterproof fabric according to claim 9, further comprising an adhesive layer provided between the base fabric and the skin layer. The moisture-permeable waterproof fabric according to claim 9, further comprising a porous layer provided between the base fabric and the skin layer.

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