Aqueous dispersion for moisture-permeable waterproof material and method for producing same

Abstract

An aqueous dispersion for a moisture-permeable waterproof material, which contains composite resin particles (C) containing a polyurethane resin (U) and a vinyl resin (V), and wherein: the polyurethane resin (U) is a reaction product of an active hydrogen component (a), a polyisocyanate component (b), and a chain extender (d); the active hydrogen component (a) contains a polyol (a3) having two or more hydroxyl groups and having an alkoxy polyoxyethylene chain.

Description

Technical Field

[0001] The present invention relates to an aqueous dispersion of a moisture-permeable waterproof material and a method for producing the same. Background Art

[0002] The method for producing a moisture-permeable waterproof fabric is generally to apply a urethane resin for the surface layer onto a release paper and dry it, then apply an adhesive thereon, dry it, and then laminate and heat-compress a fiber fabric.

[0003] In the conventional method for manufacturing moisture-permeable waterproof fabrics, a polyurethane resin having a hydrophilic segment dissolved in an organic solvent such as dimethylformamide, toluene, or methyl ethyl ketone is used as the surface layer. Since the moisture-permeable waterproof fabric is manufactured by a dry process, a large amount of solvent may be released in drainage and exhaust during manufacturing.

[0004] Under such circumstances, in order to prevent the working environment, water pollution, and air pollution, studies have been conducted on using a skin layer of an aqueous polyurethane resin containing no organic solvent.

[0005] As such an aqueous polyurethane resin, an aqueous dispersion of a polyurethane resin for a moisture-permeable waterproof material using polyethylene glycol and a diol having a carboxyl group as raw materials is known (for example, see Patent Document 1).

[0006] However, when the amount of polyethylene glycol used is increased in order to further improve the moisture permeability, the stability of the aqueous dispersion decreases, and there is a problem that the resin precipitates due to poor emulsification, changes over time, and the like.

[0007] As a method for improving such problems, aqueous polyurethane resins made of diols having ethylene oxide in their side chains are known (see, for example, Patent Document 2). However, when the aqueous polyurethane resins are processed into a film-like surface layer, the moisture permeability and water resistance are insufficient.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent No. 4283577

[0011] Patent Document 2: Japanese Patent No. 5479296 Summary of the invention

[0012] Problems to be solved by the invention

[0013] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an aqueous dispersion for a moisture-permeable waterproof material which has excellent stability over time and excellent moisture permeability and water resistance when processed into a film.

[0014] Means for solving problems

[0015] The present inventors have conducted intensive studies to solve the above problems and have achieved the present invention as a result. That is, the present invention is as follows.

[0016] [1] An aqueous dispersion for a moisture-permeable waterproof material, comprising composite resin particles (C) comprising a polyurethane resin (U) and a vinyl resin (V), wherein the polyurethane resin (U) is a reaction product of an active hydrogen component (a), a polyisocyanate component (b) and a chain extender (d), and the active hydrogen component (a) comprises a polyol (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain.

[0017] [2] The aqueous dispersion of a moisture-permeable waterproof material according to [1], wherein the weight ratio of the oxyethylene groups contained in the composite resin particles (C) is 10 to 30% by weight based on the weight of the composite resin particles (C).

[0018] [3] The aqueous dispersion of a moisture-permeable waterproof material as described in [1] or [2], wherein the ratio (W1:W2) of the weight W1 of the polyurethane resin (U) to the weight W2 of the vinyl resin (V) is 90:10 to 50:50.

[0019] [4] The aqueous dispersion of a moisture-permeable waterproof material according to any one of [1] to [3], wherein the active hydrogen component (a) further comprises a condensed polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms.

[0020] [5] A method for producing an aqueous dispersion of a moisture-permeable waterproof material, which is a method for producing an aqueous dispersion of a moisture-permeable waterproof material containing composite resin particles (C) comprising a polyurethane resin (U) and a vinyl resin (V), wherein the polyurethane resin (U) is a resin having a side chain containing a polyoxyethylene group, and the production method comprises the following steps 1 to 5.

[0021] Step 1: a step of reacting an active hydrogen component (a) and a polyisocyanate component (b) to obtain a urethane prepolymer, wherein the active hydrogen component (a) comprises a polyol having two or more hydroxyl groups and an alkoxypolyoxyethylene chain;

[0022] Step 2: a step of adding a monomer (M) having a vinyl group to the above-mentioned urethane prepolymer;

[0023] Step 3: a step of dispersing the product obtained in step 2 in an aqueous medium to obtain a dispersion of a urethane prepolymer;

[0024] Step 4: a step of extending the urethane prepolymer in the dispersion using a chain extender (d);

[0025] Step 5: A step of polymerizing the above-mentioned monomer (M) having a vinyl group, which is performed after step 4.

[0026] [6] The method for producing an aqueous dispersion of a moisture-permeable waterproof material according to [5], wherein the active hydrogen component (a) further comprises a condensed polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms.

[0027] Effects of the Invention

[0028] According to the present invention, it is possible to provide an aqueous dispersion of a moisture-permeable waterproof material which is excellent in stability over time and excellent in moisture permeability and water resistance when processed into a film. DETAILED DESCRIPTION

[0029] [1. Water-based dispersion of moisture-permeable and waterproof materials]

[0030] The aqueous dispersion for moisture-permeable waterproof material of the present invention contains composite resin particles (C) containing a polyurethane resin (U) and a vinyl resin (V). In this specification, the "aqueous dispersion for moisture-permeable waterproof material" may be simply referred to as "aqueous dispersion".

[0031] The polyurethane resin (U) is a reaction product of an active hydrogen component (a), a polyisocyanate component (b) and a chain extender (d), wherein the active hydrogen component (a) contains a polyol (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain. The polyurethane resin (U) is a resin having a side chain containing a polyoxyethylene group. In the present invention, a side chain refers to a portion branched from a main chain (a chain portion containing a urethane bond).

[0032] The active hydrogen component (a) of the material constituting the polyurethane resin (U) is a component that can react with an isocyanate compound, and contains a polyol (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain as an essential component. The active hydrogen component (a) may contain, in addition to the above-mentioned polyol (a3), a high molecular weight polyol (a1) having a number average molecular weight (hereinafter referred to as Mn) of 300 or more and / or a low molecular weight polyol (a2) having an Mn or a chemical formula weight of less than 300, which is different from the polyol (a3).

[0033] Examples of the polymer polyol (a1) having an Mn of 300 or more include polyester polyol, polyether polyol, polyether ester polyol, and castor oil-based polyol. The polymer polyol (a1) may be used alone or in combination of two or more.

[0034] Examples of the polyester polyol having an Mn of 300 or more include condensed polyester polyol having an Mn of 300 or more, polylactone polyol having an Mn of 300 or more, and polycarbonate polyol having an Mn of 300 or more.

[0035] Examples of the condensed polyester polyol having an Mn of 300 or more include polyester polyols obtained by condensing a low molecular weight polyol having an Mn or a chemical formula weight of less than 300 with a polycarboxylic acid having 2 to 20 carbon atoms or an ester-forming derivative thereof [anhydrides, lower (1 to 4 carbon atoms) alkyl esters, acid halides, etc.].

[0036] As low molecular weight polyols having an Mn or a chemical formula weight of less than 300 constituting the above-mentioned condensation-type polyester polyol, there can be cited: polyols having 2 to 20 carbon atoms; alkylene oxide (hereinafter referred to as AO) adducts having 2 to 12 carbon atoms of polyols having 2 to 20 carbon atoms and having an Mn or a chemical formula weight of less than 300; AO adducts having 2 to 12 carbon atoms of bisphenols (bisphenol A, bisphenol S, bisphenol F, etc.) and having an Mn or a chemical formula weight of less than 300; bis(2-hydroxyethyl) terephthalate and its AO adducts having 2 to 12 carbon atoms and having an Mn or a chemical formula weight of less than 300; and the like.

[0037] Examples of the polyol having 2 to 20 carbon atoms include: linear or branched aliphatic diols having 2 to 12 carbon atoms [linear alcohols such as ethylene glycol, 1,3-propanediol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-dodecanediol, diethylene glycol, triethylene glycol, and tetraethylene glycol; linear alcohols such as 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 2-methyl-1,4-butanediol, neopentyl glycol, 2,2-diethyl-1,3-propanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,6-hexanediol, 3-methyl-1,6-hexanediol, 2-methyl-1,7-heptanediol, 3-methyl-1,7-heptanediol, 4-methyl-1,7-heptanediol, 2-methyl-1,8-octanediol, 3-methyl-1,8-octanediol and 4-methyloctanediol alicyclic diols having 6 to 20 carbon atoms [1,4-cyclohexanediol, 1,3-cyclohexanedimethanol or 1,4-cyclohexanedimethanol, 1,4-cycloheptanediol, 2,5-bis(hydroxymethyl)-1,4-dioxane, 2,7-norbornanediol, tetrahydrofuran dimethanol, 1,4-bis(hydroxyethoxy)cyclohexane, 1,4-bis(hydroxymethyl)cyclohexane and 2,2-bis(4-hydroxycyclohexyl)propane, etc.]; aromatic Aliphatic diols [isophthalic alcohol or paraphthalic alcohol, bis(hydroxyethyl)benzene and bis(hydroxyethoxy)benzene, etc.]; triols with 3 to 20 carbon atoms [aliphatic triols (glycerol and trimethylolpropane, etc.)]; 4 to 8-hydric alcohols with 5 to 20 carbon atoms [aliphatic polyols (pentaerythritol, sorbitol, mannitol, sorbitan, diglycerol and dipentaerythritol, etc.); sugars (sucrose, glucose, mannose, fructose, methyl glucoside and its derivatives)]; etc.

[0038] Examples of AO having 2 to 12 carbon atoms include ethylene oxide, 1,2-propylene oxide or 1,3-propylene oxide, 1,2-butylene oxide, 1,3-butylene oxide or 2,3-butylene oxide, tetrahydrofuran, 3-methyltetrahydrofuran, styrene oxide, α-olefin oxide, and epichlorohydrin.

[0039] Examples of polycarboxylic acids having 2 to 20 carbon atoms or their ester-forming derivatives include aliphatic dicarboxylic acids (succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, decylsuccinic acid, fumaric acid, and maleic acid), alicyclic dicarboxylic acids (dimer acid, etc.), aromatic dicarboxylic acids (terephthalic acid, isophthalic acid, phthalic acid, tert-butylisophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4'-biphenyldicarboxylic acid, etc.), trivalent or higher polycarboxylic acids (trimellitic acid and pyromellitic acid, etc.), their anhydrides (succinic anhydride, maleic anhydride, phthalic anhydride, and trimellitic anhydride, etc.), their acid halides (adipoyl chloride, etc.), their low molecular weight alkyl esters (dimethyl succinate and dimethyl phthalate, etc.), and combinations thereof. Among these, aliphatic dicarboxylic acids having 2 to 10 carbon atoms and their ester-forming derivatives are preferred, and adipic acid is more preferred. The polyvalent carboxylic acid may be used alone or in combination of two or more.

[0040] As the condensation type polyester polyol having an Mn of 300 or more, from the viewpoint of excellent moisture permeability during film processing, a condensation product of an aliphatic polycarboxylic acid and Mn or a low molecular weight polyol having a chemical formula weight of less than 300 is preferred, a condensation type polyester polyol of an aliphatic polycarboxylic acid having 2 to 10 carbon atoms and Mn or a polyol having 2 to 20 carbon atoms having a chemical formula weight of less than 300 is more preferred, an ester of an aliphatic dicarboxylic acid having 2 to 10 carbon atoms and Mn or an aliphatic diol having 2 to 20 carbon atoms having a chemical formula weight of less than 300 is further preferred, and a condensation type polyester polyol of adipic acid and 3-methyl-1,5-pentanediol is particularly preferred.

[0041] Examples of polylactone polyols having an Mn of 300 or more include polylactone polyols obtained by ring-opening polymerization of lactone monomers having 3 to 12 carbon atoms (β-propiolactone, γ-butyrolactone, γ-valerolactone, ε-caprolactone, η-octalactone, 11-undecalactone, 12-dodecalactone, etc.) using the above-mentioned polyols having 2 to 20 carbon atoms as initiators. The lactone monomers may be used alone or in combination of two or more.

[0042] Examples of polycarbonate polyols having an Mn of 300 or more include polycarbonate polyols produced by condensing one or more polyols having 2 to 20 carbon atoms (preferably aliphatic diols having 3 to 9 carbon atoms, more preferably aliphatic diols having 4 to 6 carbon atoms) with a low molecular carbonate compound (e.g., dialkyl carbonates having 1 to 6 carbon atoms in an alkyl group, alkylene carbonates having 2 to 6 carbon atoms, and diaryl carbonates having 6 to 9 carbon atoms in an aryl group). Examples of the polycarbonate polyols include commercially available polycarbonate polyols such as ETERNACOLL UH series (polyhexamethylene carbonate diol, manufactured by Ube Industries, Ltd.), DURANOL G4672 (polycarbonate diol having Mn = 2000 using 1,4-butanediol / 1,6-hexanediol = 70 / 30 (molar ratio), manufactured by Asahi Kasei Chemicals Corporation).

[0043] Examples of polyether polyols having an Mn of 300 or more include compounds obtained by adding AO having 2 to 12 carbon atoms to the above-mentioned low molecular weight polyols having an Mn or a chemical formula weight of less than 300. AO may be used alone or in combination of two or more. In the latter case, block addition (tip type, balance type, active secondary type, etc.), random addition, or a combination of these may be used. Examples of AO having 2 to 12 carbon atoms include the above-mentioned AO.

[0044] The addition of AO to a low molecular weight polyol having a Mn or a chemical formula weight of less than 300 is carried out, for example, in the absence of a catalyst or in the presence of a catalyst (basic catalyst, amine catalyst, acidic catalyst, etc.) (particularly in the second half of the AO addition), at normal pressure or under pressure, in one stage or multiple stages.

[0045] Specific examples of the polyether polyol having an Mn of 300 or more include poly(oxyethylene) polyol, poly(oxypropylene) polyol, poly(oxytetramethylene) polyol, poly(oxy-3-methyltetramethylene) polyol, tetrahydrofuran / ethylene oxide copolymer polyol and tetrahydrofuran / 3-methyltetrahydrofuran copolymer polyol.

[0046] Examples of the polyether ester polyol having an Mn of 300 or more include polyether ester polyols obtained by polycondensing one or more of the above polyether polyols with one or more of the polycarboxylic acids having 2 to 20 carbon atoms or their ester-forming derivatives exemplified as the raw materials of the condensed polyester polyol having an Mn of 300 or more.

[0047] Examples of castor oil-based polyols include castor oil, partially dehydrated castor oil, polyester polyols formed from castor oil fatty acids and the above-mentioned polyols or polyoxyalkylene polyols having 2 to 20 carbon atoms (monoglyceride or diglyceride of castor oil fatty acids; monoesters, diesters or triesters formed from castor oil fatty acids and trimethylolpropane; and monoesters or diesters formed from castor oil fatty acids and polypropylene glycol (polyoxypropylene glycol), and the like), those obtained by adding AO having 2 to 12 carbon atoms to castor oil, and mixtures of two or more thereof. Examples of AO having 2 to 12 carbon atoms include the above-mentioned AO.

[0048] As the high molecular weight polyol (a1), from the viewpoint of excellent moisture permeability when processed into a film, polyester polyol is preferred, condensation-type polyester polyol and polycarbonate polyol are more preferred, condensation-type polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms is more preferred, and condensation-type polyester polyol of adipic acid and 3-methyl-1,5-pentanediol is particularly preferred.

[0049] The Mn of the high molecular weight polyol (a1) is preferably 350 or more, more preferably 1,000 to 5,000, and particularly preferably 1,500 to 3,000, from the viewpoint of excellent moisture permeability during film processing.

[0050] The Mn of the polyol in the present invention can be measured by gel permeation chromatography under the following conditions, for example.

[0051] Device: "Waters Alliance 2695" [manufactured by Waters Corporation]

[0052] Column: "Guardcolumn Super HL" (1 column), "column formed by connecting 1 each of TSKgel SuperH2000, TSKgelSuperH3000, and TSKgel SuperH4000 (all manufactured by Tosoh Corporation)"

[0053] Sample solution: 0.25 wt% tetrahydrofuran solution

[0054] Solution injection volume: 10μL

[0055] Flow rate: 0.6ml / min

[0056] Measurement temperature: 40℃

[0057] Detection device: Refractive index detector

[0058] Reference material: Standard polyethylene glycol

[0059] As the low molecular weight polyol (a2) having an Mn or a chemical formula weight of less than 300, there can be mentioned the same low molecular weight polyol as exemplified in the description of the "low molecular weight polyol having an Mn or a chemical formula weight of less than 300" as a constituent component of the condensed polyester polyol having an Mn of 300 or more; or dialkanolamines such as diethanolamine and diisopropanolamine. As the low molecular weight polyol (a2), preferably, a linear or branched aliphatic diol having 2 to 12 carbon atoms, a triol having 3 to 20 carbon atoms, and a tetrahydric to octahydric alcohol having 5 to 20 carbon atoms are preferred, and 1,4-butanediol, 1,3-propylene glycol, and trimethylolpropane are more preferred.

[0060] Examples of the polyol (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain include polyols formed by bonding an alkoxypolyoxyethylene chain to an aliphatic polyol having 3 to 20 carbon atoms (e.g., trimethylolpropane and glycerol). Preferred polyols (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain are trimethylolpropane having methoxypolyoxyethylene.

[0061] Examples of commercially available polyols (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain include TEGOMER D3403 [polyoxyethylene glycol having a number average molecular weight (Mn) = 1,200, manufactured by Evonik Industries AG], and Ymer N90, Ymer N120, and Ymer N180 [trimethylolpropane modified with polyethylene glycol having Mn = 1,200, 1,000, and 600, manufactured by Perstorp].

[0062] The active hydrogen component (a) may contain, in addition to the above-mentioned polyols (a1) to (a3), a compound (a4) containing an ionic group and an active hydrogen atom different from these. Examples of the compound (a4) include a compound (a41) containing an anionic group and an active hydrogen atom, and a compound (a42) containing a cationic group and an active hydrogen atom. The compound (a4) may be used alone or in combination of two or more.

[0063] Examples of the compound (a41) containing an anionic group and an active hydrogen atom include: a compound containing a carboxyl group as an anionic group and having at least an amino group as a group containing an active hydrogen atom [for example, amino acids (glycine, alanine, valine, lysine, aspartic acid, glutamic acid, cysteine, serine, and threonine, etc.)]; a compound containing a carboxyl group as an anionic group and having a hydroxyl group as a group containing an active hydrogen atom and having 2 to 10 carbon atoms [dihydroxyalkyl alkanoic acids (for example, 2,2-dihydroxymethylpropionic acid, 2,2-dihydroxymethylbutanoic acid, 2,2-dihydroxymethylbutanoic acid, methylheptanoic acid and 2,2-dihydroxymethyloctanoic acid), tartaric acid, etc.]; compounds containing a sulfonic acid group (sulfo group) as an anionic group, a hydroxyl group as a group containing an active hydrogen atom, and having 2 to 16 carbon atoms [3-(2,3-dihydroxypropoxy)-1-propanesulfonic acid and sulfoisophthalic acid di(ethylene glycol) ester, etc.]; compounds containing an aminosulfonic acid group as an anionic group, a hydroxyl group as a group containing an active hydrogen atom, and having 2 to 10 carbon atoms [N,N-bis(2-hydroxyethyl)aminosulfonic acid, etc.]; and salts obtained by neutralizing these compounds with a neutralizing agent.

[0064] As the neutralizing agent used for neutralizing the compound (a41) containing anionic groups and active hydrogen atoms, for example, ammonia, amine compounds having 1 to 20 carbon atoms, or alkali metal hydroxides (sodium hydroxide, potassium hydroxide, lithium hydroxide, etc.) can be cited. As the amine compounds having 1 to 20 carbon atoms, primary amines such as monomethylamine, monoethylamine, monobutylamine, and monoethanolamine; secondary amines such as dimethylamine, diethylamine, dibutylamine, diethanolamine, diisopropanolamine, and methylpropanolamine can be cited; and tertiary amines such as trimethylamine, triethylamine, dimethylethylamine, dimethylmonoethanolamine, and triethanolamine can be cited; and the like.

[0065] As the neutralizing agent used for neutralizing the compound (a41) containing an anionic group and an active hydrogen atom, a compound having a high vapor pressure at 25° C. is preferably used, from the viewpoint of excellent temporal stability of the aqueous dispersion and excellent moisture permeability when processed into a film.

[0066] From the above aspects, the neutralizing agent used for neutralizing the compound (a41) containing anionic groups and active hydrogen atoms is preferably an alkali metal hydroxide and an amine compound having 1 to 20 carbon atoms, more preferably sodium hydroxide, monomethylamine, monoethylamine, dimethylamine, diethylamine, trimethylamine, triethylamine and dimethylethylamine, and further preferably sodium hydroxide.

[0067] Among the compounds (a41) containing an anionic group and an active hydrogen atom, compounds containing a carboxyl group as an anionic group and a hydroxyl group as a group containing an active hydrogen atom and having 2 to 10 carbon atoms are preferred, from the viewpoint of excellent temporal stability of the aqueous dispersion and excellent moisture permeability when processed into a film. 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid and salts thereof are more preferred, and 2,2-dimethylolpropionic acid and salts thereof are further preferred.

[0068] Examples of the compound (a42) containing a cationic group and an active hydrogen atom include salts obtained by neutralizing a compound having a tertiary amino group as a cationic group and a hydroxyl group as a group containing an active hydrogen atom, such as a diol having 1 to 20 carbon atoms and containing a tertiary amino group [N-alkyldialkanolamines (e.g., N-methyldiethanolamine, N-propyldiethanolamine, N-butyldiethanolamine, and N-methyldipropanolamine), etc.], N,N-dialkylmonoalkanolamines (e.g., N,N-dimethylethanolamine), and trialkanolamines (e.g., triethanolamine).

[0069] Examples of the neutralizing agent used for neutralizing the compound (a42) containing a cationic group and an active hydrogen atom include monocarboxylic acids having 1 to 10 carbon atoms (e.g., formic acid, acetic acid, propionic acid, etc.), carbonic acid, dimethyl carbonate, dimethyl sulfate, methyl chloride, and benzyl chloride.

[0070] The active hydrogen component (a) may contain, in addition to the above-mentioned polyols (a1) to (a3) ​​and compound (a4), a reaction terminator (a5) different from them. Examples of the reaction terminator (a5) include monoalcohols having 1 to 20 carbon atoms (methanol, ethanol, butanol, octanol, decanol, dodecanol, myristyl alcohol, cetyl alcohol, and stearyl alcohol), and monoamines having 1 to 20 carbon atoms (monoalkylamines or dialkylamines such as monomethylamine, monoethylamine, monobutylamine, dibutylamine, and monooctylamine, and monoalkanolamines such as monoethanolamine and 2-amino-2-methylpropanol).

[0071] As the active hydrogen component (a), in addition to the polyol (a3), it is preferred that the active hydrogen component (a) further comprises a condensation-type polyester polyol of a polyhydric fatty acid having 2 to 10 carbon atoms and a polyhydric alcohol having 2 to 20 carbon atoms. It is particularly preferred that the active hydrogen component (a) further comprises a condensation-type polyester polyol of a polyhydric fatty acid having 2 to 10 carbon atoms and a polyhydric alcohol having 2 to 20 carbon atoms and comprises the low molecular weight polyol (a2).

[0072] The polyisocyanate component (b) as a material constituting the polyurethane resin (U) includes organic polyisocyanates having two or more isocyanate groups, for example, aromatic polyisocyanates having 8 to 26 carbon atoms (b1), aliphatic polyisocyanates having 4 to 22 carbon atoms (b2), alicyclic polyisocyanates having 8 to 18 carbon atoms (b3), aromatic aliphatic polyisocyanates having 10 to 18 carbon atoms (b4), and modified products of these organic polyisocyanates (b5).

[0073] Examples of the aromatic polyisocyanate (b1) having 8 to 26 carbon atoms include 1,3-phenylene diisocyanate or 1,4-phenylene diisocyanate, 2,4-toluene diisocyanate or 2,6-toluene diisocyanate (hereinafter referred to as toluene diisocyanate for short TDI), crude TDI, 4,4'-diphenylmethane diisocyanate or 2,4'-diphenylmethane diisocyanate (hereinafter referred to as diphenylmethane diisocyanate for short), The invention also includes the following: crude MDI, polyaryl polyisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5-naphthalene diisocyanate, 4,4',4"-triphenylmethane triisocyanate, and m-isocyanatobenzenesulfonyl isocyanate or p-isocyanatobenzenesulfonyl isocyanate.

[0074] Examples of the aliphatic polyisocyanate (b2) having 4 to 22 carbon atoms include ethylene diisocyanate, tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, hexamethylene diisocyanate (hereinafter referred to as HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethylhexanoate, bis(2-isocyanatoethyl)fumarate, bis(2-isocyanatoethyl)carbonate and 2-isocyanatoethyl-2,6-diisocyanatohexanoate.

[0075] Examples of the alicyclic polyisocyanate (b3) having 8 to 18 carbon atoms include isophorone diisocyanate (hereinafter referred to as IPDI), 4,4'-dicyclohexylmethane diisocyanate (hereinafter referred to as hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis(2-isocyanatoethyl)-4-cyclohexene-1,2-dicarboxylate, and 2,5-norbornane diisocyanate or 2,6-norbornane diisocyanate.

[0076] Examples of the aromatic aliphatic polyisocyanate (b4) having 10 to 18 carbon atoms include m-xylene diisocyanate, p-xylene diisocyanate, and α,α,α′,α′-tetramethylxylene diisocyanate.

[0077] As modified products (b5), there can be mentioned modified products of the above-mentioned organic polyisocyanates containing a carbamate group, a carbodiimide group, an allophanate group, a urea group, a biuret group, a uretdione group, a uretonimine group, an isocyanurate group or an oxazolidinone group [for example, modified MDI (carbamate-modified MDI, carbodiimide-modified MDI and trialkylphosphate-modified MDI, etc.), carbamate-modified TDI, a biuret form of HDI, an isocyanurate form of HDI and an isocyanurate form of IPDI].

[0078] Among these, from the viewpoint of water resistance during film processing, preferred are alicyclic polyisocyanates (b3) having 8 to 18 carbon atoms and their modified products, and more preferred are IPDI, hydrogenated MDI, and isocyanurates of IPDI. The polyisocyanate component (b) may be used alone or in combination of two or more.

[0079] The chain extender (d) is a compound that can react with an isocyanate compound. It is also a compound that can react with the reaction product (urethane prepolymer) of the active hydrogen component (a) and the polyisocyanate component (b). Examples of the chain extender (d) include water, (poly)amine compounds (d1) having anionic ion groups, (poly)amine compounds (d2) that do not have anionic ion groups and have a Mn or chemical formula weight of less than 500, etc. In addition, as the chain extender (d), the above-mentioned polyols (a1), polyols (a2), compounds (a4) and reaction terminators (a5) can also be used.

[0080] As the (poly)amine compound (d1), for example, polyamine having a carboxyl group [such as "Disponil (registered trademark) PUD" manufactured by BASF] and neutralized salts thereof can be used.

[0081] Examples of the (poly)amine compound (d2) include aliphatic polyamines having 2 to 36 carbon atoms [alkylenediamines such as ethylenediamine and hexamethylenediamine; polyalkylene polyamines having 2 to 6 carbon atoms in the alkylene group and 3 to 7 nitrogen atoms such as diethylenetriamine, dipropylenetriamine, dihexyltriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine and hexyleneheptamine (poly(di- to hexa)alkylene (carbon number 2 to 6) poly(tri- to heptamine)amines)], and alicyclic polyamines having 6 to 20 carbon atoms (1,3-diaminocyclohexane or 1,4-diaminocyclohexane, 4,4'-dicyclohexylmethanediamine or 2,4'-dicyclohexylmethanediamine, and isophorone diamine, etc.), aromatic polyamines having 6 to 20 carbon atoms (1,3-phenylenediamine or 1,4-phenylenediamine, 2,4-toluenediamine or 2,6-toluenediamine, 4,4'-methylenedianiline or 2,4'-methylenedianiline, etc.), aromatic aliphatic polyamines having 8 to 20 carbon atoms [1,3-phenylenediamine or 1,4-phenylenediamine, bis(aminoethyl)benzene, bis(aminopropyl)benzene and bis(aminobutyl)benzene, etc.], heterocyclic polyamines having 3 to 20 carbon atoms [2,4-diamino-1,3,5-triazine, piperazine and N-(2-aminoethyl)piperazine, etc.], hydrazine or its derivatives (for example, dibasic acid dihydrazides such as adipic acid dihydrazide), etc.

[0082] As the chain extender (d), aliphatic polyamines, alicyclic polyamines and polyamine compounds having anionic ion groups are preferred, and use of two or more selected from ethylenediamine, isophoronediamine and polyamines having a carboxyl group is more preferred.

[0083] In the aqueous dispersion of the present invention, the polyurethane resin (U) is a resin having a side chain containing a polyoxyethylene group.

[0084] The side chain containing a polyoxyethylene group can be introduced by reacting an active hydrogen component (a) containing a polyol (a3) ​​having two or more hydroxyl groups and having an alkoxypolyoxyethylene chain with a polyisocyanate component (b).

[0085] In the present invention, the monomer (M) having a vinyl group constituting the vinyl resin (V) includes monofunctional vinyl monomers (M1) and difunctional or higher-functional vinyl monomers (M2). The monomer (M) having a vinyl group may be used alone or in combination of two or more.

[0086] Examples of the monofunctional vinyl monomer (M1) include esters of unsaturated alcohols or hydroxystyrenes with monocarboxylic acids having 1 to 12 carbon atoms [e.g., vinyl acetate, vinyl butyrate, vinyl propionate, vinyl butyrate, isopropenyl acetate, methyl 4-vinylbenzoate, methoxyvinyl acetate, vinyl benzoate, and acetoxystyrene], (meth)aliphatic acrylates [e.g., methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, and eicosyl (meth)acrylate], (meth)acrylates having an alicyclic structure [cyclohexyl (meth)acrylate, isobutyl (meth)acrylate, and butyl (meth)acrylate] [(meth)acrylate and methyl norbornene (meth)acrylate, etc.], (meth)acrylate having an aromatic ring [(meth)acrylate benzyl and phenyl (meth)acrylate, etc.], (meth)acrylate having a hydroxyl group [(meth)acrylate-2-hydroxyethyl, etc.], (meth)acrylic acid, esters of unsaturated carboxylic acids other than (meth)acrylic acid and alcohols [(meth)acrylic acid di(cyclo)alkyl esters (two alkyl groups are straight or branched groups with 2 to 8 carbon atoms) and maleic acid di(cyclo)alkyl esters (two alkyl groups are straight or branched groups with 2 to 8 carbon atoms)], and polyoxyalkylene (carbon number 2 to 4) monohydric alcohol unsaturated carboxylic acid esters with a polymerization degree of 5 to 50 [for example, ester group-containing vinyl monomers such as methanol ethylene oxide 10 mol addition product (meth)acrylate and lauryl alcohol ethylene oxide 30 mol addition product (meth)acrylate, etc.]. The (meth)acrylate in this specification refers to acrylate and / or methacrylate.

[0087] As the monofunctional vinyl monomer (M1), from the viewpoint of moisture permeability during film processing, preferably an aliphatic (meth)acrylate, more preferably methyl (meth)acrylate.

[0088] As the monofunctional vinyl monomer (M1), one kind may be used, or two or more kinds may be used in combination. In addition, as monofunctional vinyl monomers other than those described above, for example, monofunctional vinyl monomers described in WO2020 / 105569 can be used.

[0089] Examples of the vinyl monomer (M2) having two or more functional groups include divinylbenzene, tricyclodecane dimethanol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, glycerol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 9,9-bis[4-(2- (Meth) acryloyloxyethoxy) phenyl] fluorene, ethoxylated isocyanuric acid tri(meth)acrylate, ε-caprolactone modified tri(2-(meth)acryloyloxyethyl) isocyanurate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, di(trimethylolpropane) tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate The present invention relates to a vinyl monomer (M2) having two or more functional groups, wherein the monomers (M2) are selected from the group consisting of: polyethylene glycol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol poly(meth)acrylate, tripentaerythritol poly(meth)acrylate, polypentaerythritol poly(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, allyl (meth)acrylate, triallyl isocyanurate, diallyl isocyanurate, diallyl maleate, etc. Among these, polyethylene glycol di(meth)acrylate is preferred. As the vinyl monomer (M2) having two or more functional groups, one may be used or two or more may be used in combination.

[0090] From the viewpoint of water resistance during film processing, the monomer (M) having a vinyl group is preferably a monomer containing an aliphatic (meth)acrylate, and more preferably a monomer containing methyl (meth)acrylate.

[0091] From the perspective of the temporal stability of the aqueous dispersion and the water resistance during film processing, the ratio (W1:W2) of the weight W1 of the polyurethane resin (U) to the weight W2 of the vinyl resin (V) in the aqueous dispersion is preferably 90:10 to 50:50, more preferably 80:20 to 60:40.

[0092] From the viewpoint of the temporal stability of the aqueous dispersion and the moisture permeability and water resistance during film processing, the weight proportion of the oxyethylene group contained in the composite resin particles (C) in the aqueous dispersion is preferably 10 to 30% by weight, more preferably 12 to 20% by weight, based on the weight of the composite resin particles (C).

[0093] From the perspective of the handleability and temporal stability of the aqueous dispersion, the volume average particle size (Dv) of the composite resin particles in the aqueous dispersion is preferably 0.01 to 1 μm, more preferably 0.02 to 0.7 μm, and particularly preferably 0.03 to 0.4 μm. The volume average particle size (Dv) can be measured using, for example, a light scattering particle size distribution measuring device [ELS-8000 {manufactured by Otsuka Electronics Co., Ltd.}].

[0094] The aqueous dispersion may contain an aqueous medium as a component other than the composite resin particles. Examples of the aqueous medium include water and a mixture of water and an organic solvent.

[0095] Examples of the organic solvent include ketone solvents (e.g., acetone and methyl ethyl ketone), ester solvents (e.g., ethyl acetate), ether solvents (e.g., tetrahydrofuran), amide solvents (e.g., N,N-dimethylformamide and N-methylpyrrolidone), alcohol solvents (e.g., isopropanol), and aromatic hydrocarbon solvents (e.g., toluene). The organic solvent may be used alone or in combination of two or more. As the aqueous medium, water is preferred.

[0096] From the perspective of dispersion stability, the aqueous dispersion may contain a surfactant (E). As the surfactant (E), a reactive surfactant (E1) and a non-reactive surfactant (E2) having a free radical reactive group may be cited, and one type may be used alone, or two or more types may be used in combination (including the combination of a reactive surfactant (E1) and a non-reactive surfactant (E2)). Among these, from the perspective of water resistance during film processing, a reactive surfactant (E1) is preferred.

[0097] The reactive surfactant (E1) is not particularly limited as long as it is a surfactant having radical reactivity, and specific examples thereof include Adeka Reasoap [registered trademark, manufactured by Adeka Co., Ltd.] SE-10N, SR-10, SR-20, SR-30, ER-20, ER-30, Aquaron [registered trademark, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.] HS-10, KH-05, KH-10, KH-1025, Eleminol [registered trademark, manufactured by Sanyo Chemical Industries, Ltd.] JS-20, Latemul [registered trademark, manufactured by Kao Corporation] PD-104, PD-420, PD-430, and IONNET [registered trademark, manufactured by Sanyo Chemical Industries, Ltd.] MO-200.

[0098] Examples of the non-reactive surfactant (E2) include nonionic surfactants (E21), anionic surfactants (E22), cationic surfactants (E23), amphoteric surfactants (E24), and other emulsifying and dispersing agents (E25).

[0099] Examples of the nonionic surfactant (E21) include AO addition type nonionic surfactants and polyol type nonionic surfactants. Examples of the AO addition type include ethylene oxide (hereinafter referred to as EO) adducts of aliphatic alcohols having 10 to 20 carbon atoms, EO adducts of phenol, EO adducts of nonylphenol, EO adducts of alkylamines having 8 to 22 carbon atoms, and EO adducts of poly(oxypropylene) glycol. Examples of the polyol type include fatty acid (8 to 24 carbon atoms) esters of poly(3 to 8 valence or more) alcohols (2 to 30 carbon atoms) (e.g., monostearate, monooleate, sorbitan monolaurate, sorbitan monooleate, etc.) and alkyl (4 to 24 carbon atoms) poly (polymerization degree 1 to 10) glycosides.

[0100] Examples of the anionic surfactant (E22) include: ether carboxylic acids having a hydrocarbon group having 8 to 24 carbon atoms or salts thereof [sodium lauryl ether acetate and (poly)oxyethylene (addition mole number 1 to 100) sodium lauryl ether acetate, etc.]; sulfates or ether sulfates having a hydrocarbon group having 8 to 24 carbon atoms and salts thereof [sodium lauryl sulfate, (poly)oxyethylene (addition mole number 1 to 100) sodium lauryl sulfate, (poly)oxyethylene (addition mole number 1 to 100) triethanolamine lauryl sulfate, and (poly)oxyethylene (addition mole number 1 to 100) sodium coconut oil fatty acid monoethanolamide sulfate, etc.]; sulfonates having a hydrocarbon group having 8 to 24 carbon atoms [sodium dodecylbenzenesulfonate, etc.]; Sulfosuccinates having 1 or 2 hydrocarbon groups with 8 to 24 carbon atoms; phosphates or ether phosphates having hydrocarbon groups with 8 to 24 carbon atoms and their salts [sodium lauryl phosphate and sodium (poly)oxyethylene (addition mole number 1 to 100) lauryl ether phosphate, etc.]; fatty acid salts having hydrocarbon groups with 8 to 24 carbon atoms [sodium laurate and triethanolamine laurate, etc.]; acylated amino acid salts having hydrocarbon groups with 8 to 24 carbon atoms [sodium coconut oil fatty acid methyl taurine, sodium coconut oil fatty acid sarcosinate, coconut oil fatty acid sarcosine triethanolamine, N-coconut oil fatty acid acyl-L-glutamate triethanolamine, sodium N-coconut oil fatty acid acyl-L-glutamate and sodium lauroyl methyl-β-alanine, etc.].

[0101] Examples of the cationic surfactant (E23) include quaternary ammonium salt types [stearyltrimethylammonium chloride, behenyltrimethylammonium chloride, distearyldimethylammonium chloride, and ethylsulfate lanolin fatty acid aminopropylethyldimethylammonium, etc.] and amine salt types [stearic acid diethylaminoethylamide lactylate, dilaurylamine hydrochloride, and oleylamine lactylate, etc.].

[0102] Examples of the amphoteric surfactant (E24) include betaine-type amphoteric surfactants [coconut oil fatty acid amide propyl dimethylaminoacetic acid betaine, lauryl dimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethyl imidazolinium betaine, lauryl hydroxysulfobetaine and lauroyl amide ethyl hydroxyethyl carboxymethyl betaine hydroxypropyl sodium phosphate, etc.] and amino acid-type amphoteric surfactants [sodium β-laurylaminopropionate, etc.].

[0103] As other emulsifying dispersants (E25), for example, polyvinyl alcohol, starch and its derivatives, cellulose derivatives such as carboxymethyl cellulose, methyl cellulose and hydroxyethyl cellulose, and (co)polymers containing a carboxyl group such as sodium polyacrylate, and emulsifying dispersants having a carbamate group or an ester group described in the specification of U.S. Patent No. 5,906,704 [for example, an emulsifying dispersant formed by linking polycaprolactone polyol and polyether diol with polyisocyanate], etc. can be mentioned.

[0104] When the surfactant (E) is used, the amount thereof is preferably 0.5 to 10 wt %, more preferably 1 to 3 wt % based on the weight of the vinyl group-containing monomer (M), from the viewpoint of water resistance during film processing and temporal stability of the aqueous dispersion.

[0105] The aqueous dispersion may contain a crosslinking agent, a viscosity modifier, a defoamer, a preservative, a weather stabilizer, and an antifreeze agent as optional components. As optional components, for example, the crosslinking agent, viscosity modifier, defoamer, preservative, weather stabilizer, and antifreeze agent described in International Publication No. 2020 / 105569 can be used.

[0106] From the aspect of the ease of handling of the aqueous dispersion, the solid content concentration (content of components other than volatile components) of the aqueous dispersion is preferably 20 to 65% by weight, and more preferably 25 to 55% by weight. The solid content concentration can be obtained as follows: about 1 g of the aqueous dispersion is thinly spread on a petri dish, accurately weighed, heated at 130° C. for 45 minutes using a circulating constant temperature dryer, accurately weighed after heating, and calculated The ratio (percentage) of the residual weight after heating to the weight before heating, the solid content concentration can be obtained.

[0107] The viscosity of the aqueous dispersion at 25° C. is preferably 10 to 100,000 mPa·s, more preferably 10 to 5,000 mPa·s. The viscosity can be measured using a BL type viscometer.

[0108] The pH of the aqueous dispersion at 25° C. is preferably 2 to 12, more preferably 4 to 10. The pH can be measured using a pH meter M-12 (manufactured by Horiba, Ltd.).

[0109] In the aqueous dispersion of the present invention, the urethane bond content of the polyurethane resin (U) is preferably 0.8 to 1.8 mmol / g, more preferably 0.9 to 1.4 mmol / g, based on the weight of the composite resin particles (C), from the viewpoint of mechanical strength and the like.

[0110] The urethane bond content can be determined by the N atom content quantified by a nitrogen analyzer and the 1 The ratio of the carbamate group to the urea group and the content of the allophanate group and biuret group were calculated by H-NMR quantification.

[0111] In the aqueous dispersion of the present invention, the urea bond content of the polyurethane resin (U) is preferably 0.2 to 0.7 mmol / g, more preferably 0.3 to 0.69 mmol / g based on the weight of the composite resin particles (C), from the viewpoint of mechanical strength.

[0112] The urea bond content can be determined by the N atom content quantified by a nitrogen analyzer and the 1 The ratio of the carbamate group to the urea group and the content of the allophanate group and biuret group were calculated by H-NMR quantification.

[0113] As for the nitrogen analyzer, for example, a nitrogen analyzer [ANTEK7000 (manufactured by Antec Corporation)] can be used.

[0114] about 1 H-NMR measurement was performed by the method described in "Structural Study of Polyurethane Resins by NMR: Takeda Research Institute Bulletin 34 (2), 224-323 (1975)". 1 In the H-NMR measurement, when an aliphatic is used, the weight ratio of urea groups to carbamate groups is calculated from the ratio of the integrated amount of hydrogen derived from urea groups near the chemical shift of 6 ppm to the integrated amount of hydrogen derived from carbamate groups near the chemical shift of 7 ppm, and the carbamate group and urea group contents are calculated from this weight ratio and the above-mentioned N atom content and allophanate group and biuret group content. When an aromatic isocyanate is used, the weight ratio of urea groups to carbamate groups is calculated from the ratio of the integrated amount of hydrogen derived from urea groups near the chemical shift of 8 ppm to the integrated amount of hydrogen derived from carbamate groups near the chemical shift of 9 ppm, and the urea group content is calculated from this weight ratio and the above-mentioned N atom content.

[0115] The aqueous dispersion of the present invention exhibits excellent water resistance when processed into a film. The detailed mechanism of the present invention for obtaining this effect is not clear, but it is presumed as follows.

[0116] In the aqueous dispersion containing polyurethane resin and vinyl resin prepared separately, the compatibility of the two resins is not good. In contrast, the composite resin particles contained in the aqueous dispersion of the present invention contain polyurethane resin and vinyl resin. That is, in the composite resin particles contained in the aqueous dispersion of the present invention, since there are two kinds of resins in one particle, the two kinds of resins are evenly dispersed in the aqueous dispersion, and the functions of the two kinds of resins are brought into play in a balanced manner. As a result, according to the present invention, compared with the aqueous dispersion containing polyurethane resin and vinyl resin prepared separately, the water resistance during film processing is excellent.

[0117] In addition, the aqueous dispersion of the present invention has excellent stability over time and excellent moisture permeability when processed into a film. The detailed mechanism of the present invention to obtain such effects is not clear, but it is presumed as follows.

[0118] In an aqueous dispersion of composite resin particles of a polyurethane resin having polyoxyethylene groups in the main chain (chain portion containing urethane bonds) of the polymer but not in the side chains and a vinyl resin, particles may aggregate with each other over time to generate sediment.

[0119] On the other hand, the composite resin particles in the aqueous dispersion of the present invention contain a polyurethane resin containing a polyoxyethylene group in the side chain. The aggregation of the composite resin particles is suppressed by the action of the polyoxyethylene group contained in the side chain, thereby providing an aqueous dispersion with excellent temporal stability.

[0120] [2. Method for producing aqueous dispersion of moisture-permeable waterproof material]

[0121] The method for producing an aqueous dispersion of a moisture-permeable waterproof material of the present invention is a method for producing an aqueous dispersion of a moisture-permeable waterproof material containing composite resin particles (C) comprising a polyurethane resin (U) and a vinyl resin (V), wherein the polyurethane resin (U) is a resin having a side chain containing a polyoxyethylene group, and the method comprises the following steps 1 to 5.

[0122] Step 1: a step of reacting an active hydrogen component (a) and a polyisocyanate component (b) to obtain a urethane prepolymer, wherein the active hydrogen component (a) comprises a polyol having two or more hydroxyl groups and an alkoxypolyoxyethylene chain;

[0123] Step 2: a step of adding a monomer (M) having a vinyl group to the above-mentioned urethane prepolymer;

[0124] Step 3: a step of dispersing the product obtained in step 2 in an aqueous medium to obtain a dispersion of a urethane prepolymer;

[0125] Step 4: a step of extending the urethane prepolymer in the dispersion using a chain extender (d);

[0126] Step 5: A step of polymerizing the above-mentioned monomer (M) having a vinyl group, which is performed after step 4.

[0127] According to the production method of the present invention, the aqueous dispersion of the moisture-permeable waterproof material of the present invention can be produced.

[0128] Step 1 is a step of reacting an active hydrogen component (a) containing a polyol having two or more hydroxyl groups and an alkoxypolyoxyethylene chain with a polyisocyanate component (b) to obtain a urethane prepolymer. The urethane prepolymer is a polymer containing a polyoxyethylene group in a side chain.

[0129] The active hydrogen component (a) used in step 1 contains a polyol (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain as an essential component. The active hydrogen component (a) and the polyol (a3) ​​are the same as those in the description of "1. Aqueous dispersion for moisture-permeable waterproof material" above, and the preferred ones are also the same.

[0130] The active hydrogen component (a) may contain, in addition to the above-mentioned polyol (a3), a component selected from a high molecular weight polyol (a1) having an Mn of 300 or more, a low molecular weight polyol (a2) having an Mn or a chemical formula weight of less than 300, a compound (a4) having an ionic group and an active hydrogen atom, and a reaction terminator (a5).

[0131] The polyol (a1), the polyol (a2), the compound (a4) and the reaction terminator (a5) are the same as the polyol (a1), the polyol (a2), the compound (a4) and the reaction terminator (a5) in the description of “1. Aqueous dispersion for moisture-permeable waterproof material”.

[0132] From the perspective of being able to provide a film having excellent adhesion to the substrate, the active hydrogen component (a) of step 1 is preferably a component comprising the above-mentioned polyol (a3) ​​and a condensation-type polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms. Particularly preferred is a component comprising the above-mentioned polyol (a3) ​​and a condensation-type polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms, and a low-molecular-weight polyol (a2).

[0133] The polyisocyanate component (b) used in the step 1 is the same as the polyisocyanate component (b) in the description of "1. Aqueous dispersion of moisture-permeable waterproof material", and preferred ones are also the same.

[0134] In step 1, the active hydrogen component (a) and the polyisocyanate component (b) are preferably reacted so that the equivalent ratio of the isocyanate group contained in the active hydrogen component (a) to the group containing an active hydrogen atom (referring to a hydroxyl group and an amino group, excluding a carboxyl group, a sulfonic acid group and an aminosulfonic acid group) (isocyanate group / group containing an active hydrogen atom) is 1.01 to 3, and more preferably 1.1 to 2.

[0135] The reaction temperature in step 1 is preferably 20 to 150° C., more preferably 60 to 110° C., and the reaction time is preferably 2 to 30 hours.

[0136] In step 1, a catalyst may be used to promote the reaction. Examples of the catalyst include catalysts described in International Publication No. 2020 / 105569.

[0137] In addition, in step 1, a radical scavenger may be used to suppress an abnormal increase in the viscosity of the reaction system. Examples of the radical scavenger include the radical scavengers described in International Publication No. 2020 / 105569.

[0138] Step 2 is a step of adding a monomer (M) having a vinyl group to the urethane prepolymer obtained in step 1.

[0139] Examples of the monomer (M) having a vinyl group used in step 2 include the same monomers as those mentioned in the description of “1. Aqueous dispersion of moisture-permeable waterproof material”.

[0140] As the monomer (M) having a vinyl group, from the viewpoint of water resistance during film processing, a monomer containing an aliphatic (meth)acrylate is preferred, and a monomer containing methyl (meth)acrylate is more preferred. In addition, when the above-mentioned preferred monomer is used in step 2, in the substance obtained by performing step 2, the monomer functions as an emulsifying solvent, and promotes the dispersion of the urethane prepolymer in step 3.

[0141] The ratio (Wup:Wm) of the weight Wup of the urethane prepolymer to the weight Wm of the monomer (M) having a vinyl group at the start of step 2 is preferably 90:10 to 50:50, more preferably 80:20 to 60:40.

[0142] In step 2, the temperature of the urethane prepolymer when the vinyl group-containing monomer (M) is added is preferably 30 to 60° C. After step 1 and before step 2, a step of cooling the urethane prepolymer obtained in step 1 may be performed. The cooling method is not particularly limited, and examples thereof include a method of air cooling to a desired temperature.

[0143] Step 3 is a step of dispersing the product obtained in step 2 in an aqueous medium to obtain a dispersion of a urethane prepolymer. The "product obtained in step 2" is a mixture containing a urethane prepolymer and a monomer (M) having a vinyl group.

[0144] The aqueous medium used in step 3 is the same as the aqueous medium in the description of “1. Aqueous dispersion of moisture-permeable waterproof material”, and the preferred ones are also the same.

[0145] When the obtained product in step 2 is dispersed in an aqueous medium, a surfactant can be used from the aspect of dispersion stability. As surfactants, reactive surfactants and non-reactive surfactants having free radical reactive groups can be mentioned, and one can be used alone or in combination with two or more. As surfactants, for example, reactive surfactants and non-reactive surfactants having free radical reactive groups described in International Publication No. 2020 / 105569 can be mentioned.

[0146] When the product obtained in step 2 is dispersed in an aqueous medium, the compound (a4) having an ionic group and an active hydrogen atom can be used from the viewpoint of dispersion stability.

[0147] When using a compound (a4) having an ionic group and an active hydrogen atom, the neutralizing agent used for neutralizing the compound (a41) containing anionic groups and active hydrogen atoms and the compound (a42) containing cationic groups and active hydrogen atoms can be added at any of the following times: before the urethane prepolymerization reaction (before the start of step 1), during the urethane prepolymerization reaction (during step 1), after the urethane prepolymerization reaction, before the water dispersion step (after step 1 and before step 3), during the water dispersion step (during step 3), or after the water dispersion step (after step 3). From the perspective of the stability of the aqueous dispersion, it is preferably added before the water dispersion step (before step 3) or during the water dispersion step (during step 3).

[0148] The step 3 is preferably carried out at a temperature of 0 to 100° C. and for a time of 1 to 180 minutes.

[0149] Step 4 is a step of extending the urethane prepolymer in the dispersion of the urethane prepolymer obtained in step 3 using a chain extender (d). By carrying out step 4, a dispersion of a polyurethane resin containing a monomer (M) having a vinyl group can be obtained.

[0150] The chain extender (d) used in step 4 is the same as the chain extender in the description of "1. Aqueous dispersion for moisture-permeable waterproof material", and the preferred ones are also the same. The chain extender (d) may be used alone or in combination of two or more. It should be noted that the chain extender (d) may also be used as the active hydrogen component (a) in step 1.

[0151] The step 4 is preferably carried out at a temperature of 0 to 100° C. and for a time of 1 to 240 minutes.

[0152] Step 5 is a step of polymerizing the monomer (M) having a vinyl group, which is performed after step 4. By performing step 5, the monomer (M) having a vinyl group in the polyurethane resin obtained by performing step 4 is polymerized to obtain an aqueous dispersion containing composite resin particles containing a polyurethane resin and a vinyl resin.

[0153] As the polymerization initiator used in the polymerization in step 5, there can be used: persulfate initiators such as sodium persulfate, potassium persulfate and ammonium persulfate; azo initiators such as azobisisobutyronitrile; organic peroxides such as benzoyl peroxide, cumene hydroperoxide, tert-butyl peroxybenzoate and tert-butyl hydroperoxide; hydrogen peroxide; and other common free radical polymerization initiators. These can be used alone or in combination of two or more. As the polymerization initiator, hydrogen peroxide is preferred.

[0154] The amount of the polymerization initiator used is preferably 0.05 to 5% by weight based on the weight of the monomer (M) having a vinyl group used in the polymerization.

[0155] The polymerization initiator may be added in a required amount all at once at the start of the polymerization, or may be added in divided portions at arbitrary time intervals.

[0156] In the polymerization in step 5, a reducing agent may be used together with the above-mentioned polymerization initiator as needed. Examples of such reducing agents include reducing organic compounds such as ascorbic acid, metal salts of ascorbic acid, tartaric acid, citric acid, glucose, and metal salts of formaldehyde sulfoxylate, and reducing inorganic compounds such as sodium thiosulfate, sodium sulfite, sodium bisulfite, and sodium pyrosulfite. As the reducing agent, a metal salt of ascorbic acid is preferred, and a sodium salt of ascorbic acid is more preferred.

[0157] In the polymerization, a chain transfer agent may be used as required. Examples of such chain transfer agents include n-dodecyl mercaptan, tert-dodecyl mercaptan, n-butyl mercaptan, 2-ethylhexyl mercaptoacetate, 2-mercaptoethanol, β-mercaptopropionic acid, and α-methylstyrene dimer.

[0158] As required, sodium acetate, sodium citrate, sodium bicarbonate or the like may be used as a buffer, and polyvinyl alcohol, a water-soluble cellulose derivative, an alkali metal salt of polymethacrylic acid or the like may be used as a protective colloid.

[0159] The polymerization reaction in step 5 is preferably carried out at a temperature in the range of 20°C to 150°C, more preferably 40°C to 100°C. The reaction time is preferably 1 minute to 50 hours. The polymerization reaction is preferably carried out in the presence of an inert gas. Examples of the inert gas include nitrogen and the like.

[0160] In the method for producing an aqueous dispersion of the present invention, an organic solvent may be used in any production step.

[0161] The organic solvent is not particularly limited, and examples thereof include ketone solvents having 3 to 10 carbon atoms (such as acetone, methyl ethyl ketone, and methyl isobutyl ketone), ester solvents having 2 to 10 carbon atoms (such as ethyl acetate, butyl acetate, and γ-butyrolactone), ether solvents having 4 to 10 carbon atoms (such as dioxane, tetrahydrofuran, ethyl cellosolve, and diethylene glycol dimethyl ether), amide solvents having 3 to 10 carbon atoms (such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-methylcaprolactam), sulfoxide solvents having 2 to 10 carbon atoms (such as dimethyl sulfoxide), alcohol solvents having 1 to 8 carbon atoms (such as methanol, ethanol, isopropanol, and octanol), and hydrocarbon solvents having 4 to 10 carbon atoms (such as cyclohexane, toluene, and xylene). When an organic solvent is used, the solvent may be removed in a subsequent step.

[0162] In the production method of the present invention, the aqueous dispersion after step 5 may contain a crosslinking agent, a viscosity modifier, a defoaming agent, a preservative, a weather stabilizer, an antifreeze agent, etc. Specific examples of these are the same as those described in "1. Aqueous dispersion for moisture-permeable waterproof material".

[0163] According to the production method of the present invention, a polyoxyethylene group is introduced into the side chain of the prepolymer of the polyurethane resin by performing step 1, and an aqueous dispersion containing composite resin particles containing a polyurethane resin having a polyoxyethylene group in the side chain and a vinyl resin can be obtained by further performing steps 2 to 5. As a result, according to the production method of the present invention, a film having excellent substrate adhesion, transparency and glossiness can be provided, and an aqueous dispersion having excellent mixing stability can be obtained.

[0164] [3. Use of the aqueous dispersion of the present invention]

[0165] The aqueous dispersion of the present invention and the aqueous dispersion obtained by the production method of the present invention can be applied onto a releasable substrate (such as release paper, release cloth, etc.) and then dried to form a film having moisture-permeable waterproof properties.

[0166] An example of a method for manufacturing the above-mentioned moisture-permeable and waterproof film is described. A coating liquid formed by the aqueous dispersion of the present invention is prepared, and it is applied to release paper using a knife coater, a tube coater, a rod coater, or the like. Thereafter, it is dried at about 100 to 160°C using a dryer such as an air oven for about 30 seconds to 5 minutes, thereby forming a film composed of composite resin particles. Regarding the thickness of the film, when used as a moisture-permeable and waterproof fabric, it is preferably about 10 to 50 μm. The thickness of the film can be appropriately set according to its purpose. The film thickness can be adjusted by adjusting the slit gap of the coater when applying the coating liquid, or by repeatedly applying and drying.

[0167] The film produced using the aqueous dispersion of the present invention has excellent moisture permeability and water resistance, and can therefore be suitably used in outdoor clothing for fishing or mountain climbing, ski-related clothing, windbreakers, sportswear, golf wear, raincoats, casual jackets, outdoor work clothes, gloves, shoes, mountaineering equipment such as tents, and back sheets for sanitary materials such as diapers and sanitary products that require moisture permeability.

[0168] Example

[0169] The present invention is specifically described below by way of examples, but the present invention is not limited to these examples. It should be noted that, hereinafter, parts represent parts by weight.

[0170] [Example 1]

[0171] Into a reaction apparatus equipped with a stirrer and a heater, 99.6 parts of Kuraray Polyol P-2010 [manufactured by Kuraray Co., Ltd.] as an active hydrogen component (a), 9.1 parts of 1,4-butanediol, 59.7 parts of Ymer N120 [manufactured by Perstorp], and 70.2 parts of isophorone diisocyanate as a polyisocyanate component (b) were charged, and stirred at 80° C. for 5 hours to carry out a urethanization reaction.

[0172] The reaction liquid obtained by the urethanization reaction was cooled to 60° C., 102.3 parts of methyl methacrylate was added as a monomer (M) having a vinyl group, and the mixture was cooled to 50° C. to obtain a urethane prepolymer liquid containing a monomer (M) having a vinyl group.

[0173] The temperature of the obtained urethane prepolymer liquid was adjusted to 50° C., and 532.0 parts of ion-exchanged water was added over 30 minutes while stirring at 200 rpm to obtain an aqueous dispersion of a urethane prepolymer.

[0174] To the obtained aqueous dispersion were added 76.0 parts of a 10.0 wt % aqueous solution of isophoronediamine and 47.1 parts of a 5.0 wt % aqueous solution of Disponil (registered trademark) PUD as a chain extender (d), and the mixture was stirred at 50° C. for 3 hours to carry out a chain extension reaction.

[0175] Next, the dispersion after the chain extension reaction was cooled to 40°C, and 2.1 parts of a 5.0 wt% aqueous solution of hydrogen peroxide as a polymerization initiator and 6.1 parts of a 5.0 wt% aqueous solution of sodium ascorbate as a reducing agent were added under a nitrogen flow, and polymerization was carried out by stirring at 40°C for 3 hours to obtain an aqueous dispersion (Q-1) of composite resin particles having a solid content concentration of 35.0 wt%.

[0176] [Example 2]

[0177] Into a reaction apparatus equipped with a stirrer and a heater were charged 99.0 parts of Kuraray Polyol P-2010 [manufactured by Kuraray Co., Ltd.] as an active hydrogen component (a), 7.9 parts of 1,4-butanediol, 1.8 parts of dimethylol propionic acid, 59.7 parts of Ymer N120 [manufactured by Perstorp], and 70.2 parts of isophorone diisocyanate as a polyisocyanate component (b), and the mixture was stirred at 80° C. for 5 hours to carry out a urethanization reaction.

[0178] The reaction liquid obtained by the urethanization reaction was cooled to 60° C., 102.3 parts of methyl methacrylate was added as a monomer (M) having a vinyl group, and the mixture was cooled to 50° C. to obtain a urethane prepolymer liquid containing a monomer (M) having a vinyl group.

[0179] The temperature of the obtained urethane prepolymer liquid was adjusted to 50° C., and 547.8 parts of ion-exchanged water was added over 30 minutes while stirring at 200 rpm to obtain an aqueous dispersion of a urethane prepolymer.

[0180] To the obtained aqueous dispersion were added 17.9 parts of a 5.0 wt % aqueous solution of ethylenediamine and 76.0 parts of a 10.0 wt % aqueous solution of isophoronediamine as a chain extender (d), and 9.6 parts of a 5.0 wt % aqueous solution of sodium hydroxide as a neutralizer, and the mixture was stirred at 50° C. for 3 hours to carry out a chain extension reaction.

[0181] Next, the dispersion after the chain extension reaction was cooled to 40°C, and 2.1 parts of a 5.0 wt% aqueous solution of hydrogen peroxide as a polymerization initiator and 6.1 parts of a 5.0 wt% aqueous solution of sodium ascorbate as a reducing agent were added under a nitrogen flow, and polymerization was carried out by stirring at 40°C for 3 hours to obtain an aqueous dispersion (Q-2) of composite resin particles having a solid content concentration of 35.0 wt%.

[0182] [Example 3]

[0183] An aqueous dispersion of composite resin particles (Q-3) was obtained by performing the same operation as in Example 2 except that the neutralizing agent (aqueous solution of sodium hydroxide) was not used and the amount of ion-exchanged water used was changed to 554.5 parts.

[0184] [Examples 4 to 17]

[0185] Aqueous dispersions (Q-4) to (Q-17) of composite resin particles of Examples 4 to 17 were obtained by the same method as in Example 1 using the respective raw materials described in Table 1-1 and Table 1-2.

[0186] [Comparative Example 1]

[0187] Into a reaction apparatus equipped with a stirrer and a heater, 37.0 parts of Kuraray Polyol P-2010 [manufactured by Kuraray Co., Ltd.], 116.6 parts of PEG-2000 [manufactured by Sanyo Chemical Industries, Ltd.], 6.3 parts of 1,4-butanediol, 8.6 parts of dimethylol propionic acid, 70.2 parts of isophorone diisocyanate as a polyisocyanate component (b), and 102.3 parts of methyl methacrylate as a monomer (M) having a vinyl group were added, and stirred at 80° C. for 5 hours to carry out a urethanization reaction. The obtained reaction solution was then cooled to 50° C., and 6.4 parts of triethylamine was added to obtain a urethane prepolymer solution.

[0188] The temperature of the obtained urethane prepolymer liquid was adjusted to 50° C., and 539.1 parts of ion-exchanged water was added over 30 minutes while stirring at 200 rpm to obtain an aqueous dispersion of a urethane prepolymer.

[0189] To the obtained aqueous dispersion, 76.0 parts of a 10.0 wt % aqueous solution of isophorone diamine and 47.1 parts of a 5.0 wt % aqueous solution of Disponil (registered trademark) PUD were added as a chain extender (d), and the mixture was stirred at 50° C. for 3 hours to carry out a chain extension reaction. After the chain extension reaction, a large amount of resin precipitation was observed in the aqueous dispersion, and the polyurethane resin was not uniformly dispersed in water, so the subsequent polymerization of the vinyl monomer did not proceed. Therefore, an aqueous dispersion was not obtained in this example, and no evaluation test was carried out.

[0190] [Comparative Example 2]

[0191] Into a reaction apparatus equipped with a stirrer and a heater, 107.0 parts of Kuraray Polyol P-2010 [manufactured by Kuraray Co., Ltd.] as an active hydrogen component (a), 46.6 parts of PEG-2000 [manufactured by Sanyo Chemical Industries, Ltd.], 6.3 parts of 1,4-butanediol, 8.6 parts of dimethylol propionic acid, 70.2 parts of isophorone diisocyanate as a polyisocyanate component (b), and 102.3 parts of methyl methacrylate as a monomer (M) having a vinyl group were added, and stirred at 80° C. for 5 hours to carry out a urethanization reaction. The obtained reaction solution was then cooled to 50° C., and 6.4 parts of triethylamine was added to obtain a urethane prepolymer solution.

[0192] The temperature of the obtained urethane prepolymer liquid was adjusted to 50° C., and 539.1 parts of ion-exchanged water was added over 30 minutes while stirring at 200 rpm to obtain an aqueous dispersion of a urethane prepolymer.

[0193] To the obtained aqueous dispersion were added 76.0 parts of a 10.0 wt % aqueous solution of isophoronediamine and 47.1 parts of a 5.0 wt % aqueous solution of Disponil (registered trademark) PUD as a chain extender (d), and the mixture was stirred at 50° C. for 3 hours to carry out a chain extension reaction.

[0194] Next, the aqueous dispersion after the chain extension reaction was cooled to 40° C., and 2.1 parts of a 5.0 wt % aqueous solution of hydrogen peroxide as a polymerization initiator and 6.1 parts of a 5.0 wt % aqueous solution of sodium ascorbate as a reducing agent were added under a nitrogen stream, and the mixture was stirred at 40° C. for 3 hours for polymerization to obtain an aqueous dispersion (Q'-2) of composite resin particles having a solid content concentration of 35.0 wt %. The polyurethane resin contained in the composite resin particles is a resin having no side chains containing polyoxyethylene groups.

[0195]

[0196]

[0197] Among the raw materials used in Examples 1 to 17 and Comparative Examples 1 to 3, the compositions of the raw materials represented by trade names are as follows.

[0198] ·Kuraray Polyol P-2010: condensation type polyester polyol of 3-methyl-1,5-pentanediol and adipic acid, Mn=2000 [manufactured by Kuraray Co., Ltd.]

[0199] · ETERNACOLL UH-200: polyhexamethylene carbonate diol with Mn=2000 [manufactured by Ube Industries, Ltd.]

[0200] PTMG-1000: poly(oxytetramethylene) glycol with Mn=1000 [manufactured by Mitsubishi Chemical Corporation]

[0201] PEG-2000: polyethylene glycol with Mn=2000 [manufactured by Sanyo Chemical Industries, Ltd.]

[0202] ·Ymer N120: aliphatic polyol-modified polyethylene glycol with Mn=1,000 [manufactured by Perstorp]

[0203] ·Ymer N90: aliphatic polyol-modified polyethylene glycol with Mn=1,200 [manufactured by Perstorp]

[0204] Disponil (registered trademark) PUD: modified amine having a carboxyl group (amine value: 410 mg / KOH: 40 wt% aqueous solution) [manufactured by BASF]

[0205] NeoCryl (registered trademark) A-1105: an acrylic water-based resin having a solid content of 50% by weight [manufactured by Covestro] (used only in Comparative Example 3)

[0206] "PEG#400 dimethacrylate" in Table 1-1 and Table 1-2 is dimethacrylate of polyethylene glycol having Mn=400.

[0207] [Comparative Example 3]

[0208] Into a reaction apparatus equipped with a stirrer and a heater, 99.6 parts of Kuraray Polyol P-2010 [manufactured by Kuraray Co., Ltd.] as an active hydrogen component (a), 9.1 parts of 1,4-butanediol, 59.7 parts of Ymer N120 [manufactured by Perstorp], and 70.2 parts of isophorone diisocyanate as a polyisocyanate component (b) were charged, and stirred at 80° C. for 5 hours to carry out a urethanization reaction.

[0209] After the obtained reaction liquid was cooled to 60° C., 436.2 parts of ion exchange water adjusted to 60° C. was added over 30 minutes while stirring at 200 rpm to obtain an aqueous dispersion of a urethane prepolymer.

[0210] To the obtained aqueous dispersion were added 76.0 parts of a 10.0 wt % aqueous solution of isophoronediamine and 47.1 parts of a 5.0 wt % aqueous solution of Disponil (registered trademark) PUD as a chain extender (d), and the mixture was stirred at 60° C. for 3 hours to carry out a chain extension reaction.

[0211] Next, the dispersion after the chain extension reaction was cooled to 25° C., and 204.6 parts of an acrylic water-based resin NeoCryl (registered trademark) A-1105 [manufactured by Covestro] were mixed to obtain an aqueous dispersion (Q'-3) having a solid content concentration of 35.0% by weight containing a polyurethane resin and an acrylic resin. The polyurethane resin contained in the aqueous dispersion (Q'-3) was not compounded with an acrylic water-based resin (an example of a vinyl resin). The polyurethane resin contained in the aqueous dispersion was a resin having a side chain containing a polyoxyethylene group.

[0212] The “total weight of resins” in Table 2 refers to the total weight of the polyurethane resin and the acrylic aqueous resin contained in the aqueous dispersion.

[0213] [Table 2]

[0214]

[0215] [Evaluation test]

[0216] The aqueous dispersions (Q-1) to (Q-17) of Examples 1 to 17 and the aqueous dispersions (Q'-2) to (Q'-3) of Comparative Examples 2 and 3 were used to perform the following procedures to evaluate the stability of the aqueous dispersions over time and the moisture permeability and water pressure resistance of the films produced using the aqueous dispersions. The evaluation results are shown in Tables 1-1, 1-2, and 2.

[0217] [Temporal stability of aqueous dispersion]

[0218] The aqueous dispersions of Examples 1 to 17 and Comparative Examples 2 to 3 were left to stand at 40° C. for 7 days, and the generation of sediment was visually evaluated. The case where no sediment was generated was marked as ○, and the case where sediment was generated was marked as ×.

[0219] [moisture permeability]

[0220] The aqueous dispersion of each example was applied on release paper so that the film thickness of the film after drying was 20 μm, and dried at 80° C. for 10 minutes and further at 120° C. for 1 minute to obtain a film (sheet material) formed by filming the aqueous dispersion. The moisture permeability (A-1 moisture permeability and B-1 moisture permeability) of the obtained film was measured.

[0221] (A-1 moisture permeability)

[0222] The moisture permeability (A-1 moisture permeability) of the film is measured based on the A-1 method (calcium chloride method) of JIS L-1099-2012. If the A-1 moisture permeability is 2000 g / m 2 ·24 hours or more is considered good.

[0223] (B-1 moisture permeability)

[0224] The moisture permeability (B-1 moisture permeability) of the film is measured based on the B-1 method (potassium acetate method) of JIS L-1099-2012. If the B-1 moisture permeability is 30000 g / m 2 ·24 hours or more is considered good.

[0225] [Water pressure resistance (water resistance)]

[0226] The aqueous dispersion of each example was coated on release paper in such a way that the film thickness of the dried film reached a thickness of 20 μm, dried at 80° C. for 10 minutes, and further dried at 120° C. for 1 minute to obtain a film for water resistance measurement. For the obtained film for water resistance measurement, the water pressure resistance was measured according to JIS L1092-1998 (high water pressure resistance method). In the case where the test piece is elongated due to the application of water pressure, Nylon Taffeta (density: equivalent to warp + weft = 210 roots / 2.54 cm) is stacked on the test piece and then installed in a testing machine for measurement. The water pressure resistance is good if it is 10000 mmH2O or more. The upper limit is 20000 mmH2O.

[0227] According to the results shown in Table 1-1, Table 1-2 and Table 2, the aqueous dispersions of the examples have excellent temporal stability, and the films formed using the aqueous dispersions of the examples have excellent moisture permeability and water resistance. On the other hand, it is known that the aqueous dispersion of Comparative Example 2 containing a polyurethane resin containing polyoxyethylene in the main chain and not having polyoxyethylene in the side chain has poor temporal stability, and in the case of the aqueous dispersion of Comparative Example 3 not containing composite resin particles of polyurethane resin and vinyl resin, the water resistance of the film formed using the aqueous dispersion is poor.

[0228] Industrial Applicability

[0229] The aqueous dispersion of the present invention and the aqueous dispersion obtained by the production method of the present invention are excellent in stability over time and excellent in moisture permeability and water resistance when processed into a film. Therefore, they are particularly useful in the application of aqueous dispersions for moisture-permeable waterproof materials used in outdoor clothing for fishing or mountaineering, ski-related clothing, windbreakers, sportswear, golf wear, raincoats, casual jackets, outdoor work clothes, gloves, shoes, and mountaineering equipment such as tents.

Claims

1. An aqueous dispersion of a moisture-permeable waterproof material, comprising composite resin particles (C) comprising a polyurethane resin (U) and a vinyl resin (V), wherein: The polyurethane resin (U) is a reaction product of an active hydrogen component (a), a polyisocyanate component (b) and a chain extender (d), wherein the active hydrogen component (a) contains a polyol (a3) ​​having two or more hydroxyl groups and an alkoxypolyoxyethylene chain.

2. The aqueous dispersion of a moisture-permeable waterproof material according to claim 1, wherein The weight ratio of the oxyethylene group contained in the composite resin particle (C) is 10% by weight to 30% by weight based on the weight of the composite resin particle (C).

3. The aqueous dispersion of a moisture-permeable waterproof material according to claim 1 or 2, wherein The ratio (W1:W2) of the weight W1 of the polyurethane resin (U) to the weight W2 of the vinyl resin (V) is 90:10 to 50:

50.

4. The aqueous dispersion of a moisture-permeable waterproof material according to claim 1 or 2, wherein The active hydrogen component (a) further includes a condensed polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms.

5. A method for producing an aqueous dispersion of a moisture-permeable waterproof material, which is a method for producing an aqueous dispersion of a moisture-permeable waterproof material containing composite resin particles (C) comprising a polyurethane resin (U) and a vinyl resin (V), wherein: The polyurethane resin (U) is a resin having a side chain containing a polyoxyethylene group, and the production method comprises the following steps 1 to 5: Step 1: a step of reacting an active hydrogen component (a) and a polyisocyanate component (b) to obtain a urethane prepolymer, wherein the active component (a) comprises a polyol having two or more hydroxyl groups and an alkoxypolyoxyethylene chain; Step 2: a step of adding a monomer (M) having a vinyl group to the urethane prepolymer; Step 3: a step of dispersing the product obtained in step 2 in an aqueous medium to obtain a dispersion of a urethane prepolymer; Step 4: a step of extending the urethane prepolymer in the dispersion using a chain extender (d); Step 5: A step of polymerizing the monomer (M) having a vinyl group, which is performed after step 4.

6. The method for producing an aqueous dispersion of a moisture-permeable waterproof material according to claim 5, wherein: The active hydrogen component (a) further includes a condensed polyester polyol of a polycarboxylic acid having 2 to 10 carbon atoms and a polyol having 2 to 20 carbon atoms.

Images