JP2003165818A - Method for production of polyurethane resin aqueous dispersion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fine aqueous dispersion of a polyurethane resin without use or little use of organic solvent. <P>SOLUTION: The method produces the polyurethane aqueous dispersion (B) by mixing an aqueous dispersion obtained by dispersedly emulsifying a mixture (A) comprising an isocyanate terminated prepolymer (a) including an ionic group and/or a group forming an ion and a reactive diluent (b) having no isocyanate group in an aqueous medium and then carrying out a chain extension by mixing the dispersion with a chain extender, and the reactivity of the reactive group of the (b) with the isocyanate group is set as lower than that of the isocyanate group with a secondary amino group, and the (b) has 0.1-10 Pa.s of viscosity. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an aqueous dispersion of a polyurethane resin, more specifically, it does not contain an organic solvent,
Alternatively, the present invention relates to a polyurethane resin aqueous dispersion having a low organic solvent content.

[0002]

2. Description of the Related Art From the viewpoints of flammability of organic solvents and safety to humans, an aqueous polyurethane dispersion prepared in the absence of an organic solvent or in the presence of a trace amount of an organic solvent has been proposed. For example, in the absence of an organic solvent, an isocyanate group-terminated prepolymer is formed from excess diisocyanate, an organic polyol, and a difunctional isocyanate-reactive component that can be an ionic group, and this is diluted with an isocyanate monomer and further neutralized. After that, a method of contact-mixing and dispersing with water or an aqueous amine solution is proposed, and the publication describes that the use of an isocyanate monomer is preferable as a means for reducing the viscosity of a high-viscosity isocyanate prepolymer ( See, for example, Patent Document 1.). Further, it has been proposed that a liquid tackifying resin is preferably used as a viscosity reducing agent for the isocyanate group-terminated prepolymer (see, for example, Patent Document 2).

[0003]

[Patent Document 1] Japanese Unexamined Patent Publication No. 9-52929

[Patent Document 2] Japanese Patent Laid-Open No. 2000-191740

[0004]

However, since the isocyanate monomer is highly reactive, there is a problem that fine particles cannot be obtained because the particles become coarse in the process of chain extension after emulsification at a high concentration. Further, when the liquid tackifying resin is mixed and emulsified with the isocyanate group-terminated prepolymer, there is a problem that the hydrophilicity of the mixture is lowered and fine particles cannot be obtained.

[0005]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve the above problems, and as a result, by using a specific reactive diluent, without using an organic solvent or in an extremely small amount. The present invention has been completed by finding that it is possible to obtain a polyurethane aqueous dispersion having fine particles only by using it. That is, the present invention provides a mixture (A) comprising an isocyanate group-terminated prepolymer (a) containing an ionic group and / or an ion forming group and a reactive diluent (b) having no isocyanate group in an aqueous medium. A method for producing a polyurethane resin aqueous dispersion (B), which comprises mixing an aqueous dispersion obtained by emulsification and dispersion with an extender to extend the chain of (a) to produce a polyurethane resin aqueous dispersion (B), the reaction of (b) The reactivity between the reactive group and the isocyanate group is lower than the reactivity between the secondary amino group and the isocyanate group, and (b) is 0.1
A method for producing a polyurethane resin aqueous dispersion having a viscosity of 10 Pa · s; a polyurethane resin aqueous dispersion obtained by the production method; a curable polyurethane resin in which a crosslinking agent is further added to the aqueous dispersion. Aqueous dispersion (C); and applying these aqueous dispersions to a substrate,
A polyurethane resin molded body that is cured at room temperature or under heating.

The isocyanate group-terminated prepolymer (a) containing an ionic group and / or an ion-forming group which constitutes the mixture (A) in the present invention is an organic polyisocyanate (a1), a polymer polyol (a2) and It is composed of an active hydrogen compound (a3) containing an ionic group and / or an ion forming group.

(A1) includes diisocyanate and 3
Include functional or higher polyfunctional isocyanates;
For example, carbon number (excluding carbon in NCO group, the same applies below)
6-20 aromatic polyisocyanate, 2-18 carbon atoms
Aliphatic polyisocyanates, alicyclic polyisocyanates having 6 to 15 carbon atoms, araliphatic polyisocyanates having 8 to 15 carbon atoms and modified products of these polyisocyanates (urethane group, carbodiimide group, allophanate group, buret group) , Uretdione groups, uretoimine groups, isocyanurate groups, oxazolidone group-containing modified products, etc.) and mixtures of two or more thereof.

Specific examples of the above aromatic polyisocyanates include 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6.
-Tolylene diisocyanate (TDI), crude TDI,
2,4'- and / or 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3 '-Dimethyl-4,4'-
Diisocyanatodiphenylmethane, crude MDI [crude diaminodiphenylmethane [condensation product of formaldehyde with aromatic amine (aniline) or a mixture thereof;
A mixture of diaminodiphenylmethane and a small amount (for example, 5 to 20% by weight) of a trifunctional or higher-functional polyamine], a phosgene compound; polyarylpolyisocyanate], 1,5-
Mention may be made of naphthylene diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, m- and p-isocyanatophenylsulfonyl isocyanate.

Specific examples of the aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,
6,11-undecane triisocyanate, 2,2,4
-Trimethylhexamethylene diisocyanate, lysine diisocyanate (2,6-diisocyanatomethylcaproate), bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2
-Isocyanatoethyl-2,6-diisocyanatohexanoate.

Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPD).
I), dicyclohexylmethane-4,4'-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis (2-isocyanatoethyl) -4-cyclohexene-
1,2-dicarboxylate, 2,5- and / or 2,6-norbornane diisocyanate are mentioned.

Specific examples of the araliphatic polyisocyanate include m- and / or p-xylylene diisocyanate and α, α, α ', α'-tetramethylxylylene diisocyanate.

The modified polyisocyanate may be modified MDI (urethane modified MDI, carbodiimide modified MDI, trihydrocarbyl phosphate modified MDI), urethane modified TDI, burette modified HD.
I, modified products of polyisocyanates such as isocyanurate-modified HDI and isocyanurate-modified IPDI, and mixtures of two or more kinds thereof (for example, combined use of modified MDI and urethane-modified TDI (isocyanate group-containing prepolymer)).

(A2) includes polyether polyol (p1), polyester polyol (p2), polyolefin polyol (p3) and polymer polyol (p2).
4), epoxy polyol (p5) and the like.

(P1) has a structure in which an alkylene oxide (hereinafter abbreviated as AO) is ring-opened and added to a low molecular weight compound having two or more active hydrogen atoms by using a polymerization catalyst, and active hydrogen. AO is subjected to ring-opening polymerization using a polymerization catalyst in the absence of a low molecular weight compound having atoms.

As the addition catalyst used in the above ring-opening addition, anion addition polymerization catalyst (for example, alkali metal hydroxide such as sodium hydroxide, potassium hydroxide, cesium hydroxide), cation addition polymerization catalyst, A coordination anion addition polymerization catalyst and the like can be mentioned. Of these, economics,
From the viewpoint of productivity, production with an anion addition polymerization catalyst is preferable. The production by anionic polymerization can be performed by reacting the above-mentioned monomer while heating the compound containing active hydrogen and the above-mentioned polymerization catalyst. The reaction temperature is 40 to 150 ° C, preferably 90 to 130 ° C. Examples of the catalyst used in the above ring-opening polymerization include reaction products of an organozinc compound and a polyol or a polyhydric phenol described in JP-B-39-19561.

In the above, compounds having two or more active hydrogen atoms include polyhydric alcohol (p11), polyhydric phenol (p12), polycarboxylic acid (p13), hydroxycarboxylic acid (p14) and primary monoamine. (P1
5), polyamine (p16) and polythiol (p1)
7) is contained and the number average molecular weight per active hydrogen atom (by GPC measurement. The same applies hereinafter, abbreviated as Mn) is less than 300 (preferably 30 to 250).

Examples of (p11) are dihydric alcohols such as [linear aliphatic diols (ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4
-Butanediol, 1,5-pentanediol, 1,6
-Hexanediol, etc.), branched aliphatic diol (1,
2-propylene glycol, neopentyl glycol,
3-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 1,2-, 1,3-
Or 2,3-butanediol), and cycloaliphatic diols (described in U.S. Pat. No. 4,990,545; cyclohexanedimethanol, cyclohexylene glycol, hydrogenated bisphenol A, etc.)]; 3
-10 or more polyhydric alcohols such as alkane polyols (glycerin, trimethylolpropane, pentaerythritol, sorbitol, and their intermolecular or intramolecular dehydration products [dipentaerythritol, polyglycerin (polymerization degree 2 to 8)] , Sorbitan, etc.], saccharides and their derivatives (glycosides) (sucrose, methylglucoside, etc.); and mixtures of two or more thereof.

Examples of (p12) include monocyclic polyhydric phenols [hydroquinone, resorcin, catechol, phloroglysin, etc.], bisphenols [bisphenol A, bisphenol F, bisphenol S, and US Pat. No. 4,990,545. These halides described (for example, tetrabromobisphenol A) and the like] can be mentioned.

(P13) is an aliphatic polycarboxylic acid having 2 to 8 or more carboxyl groups,
Eg saturated and unsaturated aliphatic polycarboxylic acids [aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid,
Glutaric acid, ethylsuccinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid and mesaconic acid, and unsaturated monocarboxylic acids (eg acrylic acid , Methacrylic acid, crotonic acid and isocrotonic acid) or polymers of unsaturated dicarboxylic acids having a degree of polymerization of 2 to 8 (maleic acid dimer, itaconic acid dimer, acrylic acid pentamer, methacrylic acid Alicyclic polycarboxylic acid, for example, alicyclic dicarboxylic acid [1,2- and 1,3-cyclopentanedicarboxylic acid, 1,2-, 1,3-, 1,4- Cyclohexanedicarboxylic acid, etc.], polymerized fatty acids [dimer acid and trimer acid (unsaturated fatty acids such as linoleic acid and linoleic acid Body and trimers, etc.)]; aromatic polycarboxylic acids [phthalic acid, isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, trimellitic acid, pyromellitic acid] and the like.

(P14) is a compound having at least one hydroxyl group and at least one carboxyl group in one molecule,
Examples include aliphatic hydroxycarboxylic acids such as glycolic acid, lactic acid, glyceric acid, tartaric acid and ricinoleic acid, and aromatic hydroxycarboxylic acids such as salicylic acid.

As (p15), an aliphatic primary monoamine having 1 to 20 carbon atoms [monoalkylamine (methylamine, ethylamine, propylamine, n-butylamine, etc.) and monoalkenylamine (oleylamine, etc.)], oil Examples include cyclic primary monoamines (such as cyclohexylamine), and aromatic primary monoamines (such as benzylamine and aniline).

Examples of (p16) include aliphatic polyamines [alkylenediamine (having 2 to 18 carbon atoms), polyalkylene (having 2 to 6 carbon atoms) polyamine (containing 3 to 25 amino groups), and alkyls thereof. (C1-C1
8) Substituted derivative; specifically, ethylenediamine, propylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, dipropylenetriamine, N-methylaminoethylamine, etc.], aromatic polyamine (having 6 to 20 carbon atoms) [2, 4- and 2,
6-Tolylenediamine, 4,4'- and 2,4'-diphenylmethanediamine, polymethylenepolyphenylenepolyamine and triphenylmethanetriamine, etc.]
Is mentioned.

As (p17), a polyhydric alcohol (p
Examples thereof include those having a structure in which the hydroxyl group of 11) is a thiol group, and specific examples thereof include ethylenedithiol, propylenedithiol, 1,4-butanedithiol and dodecanedithiol.

Examples of AO include alkylene oxides having 2 to 18 carbon atoms, such as ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO),
1,2-, 1,3-, 1,4- and 2,3-butylene oxide, styrene oxide, α-olefin oxide having 5 to 10 or 11 to 18 carbon atoms, epichlorohydrin and a combination of two or more thereof ( Block and / or random addition).

Examples of (p1) include polyether diols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol and EO and / or PO adducts of bisphenol A, and EO and / or PO adducts of glycerin. Such branched polyether polyols may be mentioned. (P1)
Among them, preferred are low molecular weight polyols (particularly aliphatic diols) to which AO (particularly PO) is added,
It is preferable that 30% or more of the total weight of AO is PO.

Examples of (p2) include polycondensates of polycarboxylic acids and polyols (p21), polylactone polyols (p22) and polycarbonate polyols (p23).

The polycarboxylic acid constituting (p21) includes the above-mentioned (p13) and their ester-forming derivatives (anhydride, acid halide, lower alkyl ester). Of these, dicarboxylic acids are preferable, and aliphatic dicarboxylic acids are particularly preferable. The polyol constituting (p21) includes the above-mentioned (p11) and (p1), preferably (p11), and particularly a dihydric alcohol. Specific examples of (p21) include poly (ethylene adipate) diol, poly (butylene adipate) diol, and poly (hexamethylene adipate).
Diol, poly (neopentyl adipate) diol,
Examples thereof include poly (ethylene / butylene adipate) diol, poly (neopentyl / hexyl adipate) diol, poly (3-methylpentyl adipate) diol, and poly (butylene isophthalate) diol.

(P22) is obtained by ring-opening polymerization of a lactone having 3 to 12 carbon atoms (eg caprolactone) in the presence of a polyhydric alcohol, and specifically,
Examples thereof include polycaprolactone diol and poly-3-methylvalerolactone diol.

(P23) is obtained by ring-opening polymerization of an alkylene carbonate having 2 to 12 carbon atoms in the presence of a polyhydric alcohol, and specific examples thereof include polyhexamethylene carbonate diol.

Among (p2), the preferable one is (p2
1).

In (p3), an olefin (1,3-butadiene, an α-olefin having 8 to 18 carbon atoms, etc.) and, if necessary, a small amount (for example, 15 to 20% by weight) of another monomer (for example, styrene, (Acrylonitrile, etc.) (Co)
A (co) polymer having a hydroxyl group at the terminal obtained by polymerization is included. Specific examples thereof include polybutadiene glycol derived from polybutadiene and polyolefin glycol derived from α-olefin having 8 to 18 carbon atoms. Further, (p3) also includes hydrogenated polybutadiene glycol obtained by adding hydrogen to an unsaturated double bond of polybutadiene glycol.

For (p4), a nitrile group-containing vinyl monomer such as (meth) acrylonitrile, styrene, and / or a (meth) acrylic acid alkyl ester are polymerized in the presence of a polyether polyol and / or a polyester polyol. It includes those obtained.

Examples of (p5) include addition condensation products of bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.) and epichlorohydrin (number of bisphenol skeletons: 3 to 20).

The number of hydroxyl groups in (a2) is 2 or 3 per molecule, and the average of two or more (a2) is usually 2.
It is 0 to 2.5, and preferably 2.0 to 2.2.
Mn per hydroxyl group is usually 400 to 2,000, preferably 500 to 1,700. 400 ~
When it is 2,000, the polyurethane fine particles show good flexibility.

The ion-forming group-containing active hydrogen compound of (a3) includes an anion-forming group (carboxyl group,
Examples include compounds having one sulfonic acid group, sulfamic acid group) or cation-forming group (tertiary amino group) and active hydrogen (2 to 4 hydroxyl groups or one primary amino group). The equivalent weight per active hydrogen is preferably 100 to 500. Among the active hydrogen compounds having an anion-forming group, as the carboxyl group-containing active hydrogen compound (a31), dialkylol alkanoic acid [(for example, 2,2-dimethylolpropionic acid (hereinafter DMPA
Abbreviated), 2,2-dimethylolbutanoic acid, 2,2-dimethylolheptanoic acid, 2,2-dimethyloloctanoic acid, etc.], amino acids (2-aminoethanoic acid, etc.),
As the sulfonic acid group-containing active hydrogen compound (a32), a sulfonic acid group-containing diol [3- (2,3-dihydroxypropoxy) -1-propanesulfonic acid (hereinafter referred to as DHP
Abbreviated as S), etc.], aminosulfonic acid (2-aminoethanesulfonic acid, 3-aminopropanesulfonic acid, etc.)
Can be given. As the sulfamic acid group-containing active hydrogen compound (a33), an AO adduct of N, N-bis (2-hydroxyalkyl) sulfamic acid salt (addition mole number 1 to
8 mol). Examples of the tertiary amino group-containing active hydrogen compound (a34) include triethanolamine and 2-methyldiethanolamine. Also, (a
As the ionic group-containing active hydrogen compound of 3),
Anion-forming group-containing active hydrogen compound (a31, a
32) is an isocyanate non-reactive base such as a tertiary amine [trialkylamine having 1 to 8 carbon atoms in the alkyl group: eg triethylamine, diethylbutylamine etc.] or alkali metal [sodium, potassium etc.]
Or a salt obtained by neutralizing the tertiary amino group with an isocyanate non-reactive acid (aliphatic carboxylic acid having 2 to 8 carbon atoms such as acetic acid or propionic acid).

The viscosity of (a) is preferably 10 to 50 Pa · s, more preferably 15 to 40 Pa · s at the emulsion dispersion temperature, for example 90 ° C.

The production method of (a) is not particularly limited, but for example, a method of simultaneously reacting (a1) to (a3) in the absence of an organic solvent, a method of reacting (a1) and (a2) Examples thereof include a method of reacting with (a3) after the reaction, a method of reacting with (a1) and (a3) and then reacting with (a2), and the like, but any method can be used for production. The reaction temperature is usually 30 to 100 ° C, preferably 40 to 80
℃. In the reaction, the equivalent amount of the isocyanate group of (a1) is usually 2 to 1.2, preferably 1.9, with respect to the equivalent amount of the active hydrogen groups of (a2) and (a3).
~ 1.3. If it is less than 2, the amount of free isocyanate is small and it is easy to obtain fine particles. If it is 1.2 or more, the viscosity of the prepolymer is not too high and it is easy to emulsify.
The content of (a3) in (a) is usually 0.5 to 6% by weight, preferably 0.8 to 5% by weight. If it exceeds 0.8% by weight, sufficient hydrophilicity can be imparted to the prepolymer, which facilitates emulsification. The NCO% in (a) is usually 0.5 to 2%, preferably 0.6 to 1.5%.

The reactive diluent (b) which constitutes the mixture (A) in the present invention is a compound which does not contain an isocyanate group at the terminal and has a functional group capable of reacting with the below-mentioned cross-linking agent. It is a compound which sometimes reduces the viscosity of (a) and reacts with the below-mentioned cross-linking agent when the aqueous dispersion (B) is dried.

(B) is preferably liquid at 30 ° C., and the viscosity at the emulsion dispersion temperature, for example, 90 ° C. is preferably 0.1 to 10 Pa · s, more preferably 0.2.
~ 8 Pa · s. (All viscosities are measured with a B-type viscometer)

The reactive group contained in (b) is 90 ° C.
The reactivity of the reactive group in (b) with the isocyanate in (a) is lower than the reactivity of the secondary amino group with the isocyanate group, and the aqueous dispersion (B) was dried. There is no particular limitation as long as it is a group that reacts with the crosslinking agent at times. It is preferably a group having a reactivity ratio of 0.03 or less, more preferably less than 0.02, as compared with the reactivity of the secondary amino group. The above reactivity ratios compared to the reactivity of secondary amino groups are shown in JHSaunders, KCFrisch, 'Polyurethanes: C
hemistry and Tecnology: Part1: 205, Interscience Pub
The reactivity ratios described in lishers, 1961 can be used. Examples of the reactive group contained in (b) include carbohydrazide group (reactivity ratio 0.018), hydroxyl group [primary hydroxyl group (reactivity ratio 0.02, secondary hydroxyl group (reactivity ratio 0.008)).
6) Tertiary hydroxyl group (reactivity ratio 0.00006)], carboxyl group (reactivity ratio 0.003), radical polymerizable unsaturated group (reactivity ratio less than 0.0002), glycidyl group (reactivity ratio 0 (Less than 0.0002), a silyl group (reactivity ratio less than 0.0002), and the like.

As (b), a polyurethane-based reactive diluent (b1), a polyether-based reactive diluent (b2),
Polyester diluent (b3), Epoxy diluent (b
4), a polyolefin-based diluent (b5), a polyamide-based diluent (b6), a poly (meth) acrylate-based diluent (b7), and a combination of two or more of these.

As (b1), among the active hydrogen group-terminated polymers obtained from the organic polyisocyanate (a1) and the excess equivalent amount of (a2), active hydrogen having a reactivity with an isocyanate group lower than that of a secondary amino group is used. Those having a containing group at the end (b11), and excess equivalents of (a1) and (a
Obtained by reacting the isocyanate group-terminated prepolymer obtained from 2) with a compound (c1) containing an active hydrogen-containing group that reacts with an isocyanate group and a reactive group (group that reacts with a crosslinking agent) other than this group. The compound (b12) can be mentioned. Of these, (b12) is preferred.

Of (a2) used for (b11),
Preferable ones are those which are liquid at 30 ° C. For example, among the above-mentioned (p1), Mn per hydroxyl group containing 90% or more of PO is 400 to 2000. Among (p2), a linear aliphatic diol (having 2 to 6 carbon atoms) and / or a branched aliphatic diol (having 3 to 8 carbon atoms) and an aliphatic dibasic acid (having 4 to 4 carbon atoms)
Mn per hydroxyl group derived from 8) is 400-
2000 is exemplified. In (p3), M
Examples of n are 1000 to 3000. Among these, (p1) or (p2) is more preferable from the viewpoint of compatibility with (a).

Examples of (c1) used in (b12) include an active hydrogen group-containing compound (c11) having a hydrazino group in the molecule, an active hydrogen group containing compound (c12) having a carboxyl group in the molecule, A compound containing a hydroxyl group and an amino group (c13), an active hydrogen group-containing compound containing a hydrolyzable silyl group in the molecule (c14),
Examples thereof include an active hydrogen group-containing compound (c15) having an unsaturated double bond group in the molecule and an active hydrogen group-containing compound (c16) containing a glycidyl group in the molecule.

Examples of (c11) include hydrazine (including hydrazine hydrate) and condensates of hydrazine and an aliphatic dibasic acid (having 2 to 8 carbon atoms) (carbodihydrazide, adipic acid dihydrazide, etc.), and (b12). Hydrazine hydrate (hereinafter abbreviated as HDH) is preferable because it can be obtained in high purity.

(C12) has one carboxyl group and 1
C3-C8 compounds having one hydroxyl group (lactic acid, etc.), C4-C8 compounds having one carboxyl group and two hydroxyl groups (dimethylolpropionic acid, dimethylolbutanoic acid, etc.) To be

(C13) is a compound having 2 to 8 carbon atoms and having 1 amino group and 1 hydroxyl group (monoethanolamine: hereinafter abbreviated as MEA, etc.), 1 amino group and 2
Examples thereof include compounds having 4 to 10 carbon atoms and having hydroxyl groups (diethanolamine and the like).

(C14) is an aminosilane compound such as γ-amino-propyltrimethoxysilane (hereinafter referred to as A
(Abbreviated as PMS), γ-aminopropyltriethoxysilane and the like.

Examples of (c15) include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl acrylate (hereinafter abbreviated as HEA), 2-hydroxyethyl methacrylate and 3-hydroxypropyl (meth) acrylate.

(C16) is a (poly) alkylene glycol monoglycidyl ether such as (poly) ethylene glycol (polymerization degree 1 to 20) monoglycidyl ether [eg ethylene glycol monoglycidyl ether (hereinafter abbreviated as EGMG)], ( Examples thereof include poly) propylene glycol (degree of polymerization 1 to 20) monoglycidyl ether and the like.

The Mn of (b) is preferably 900 to 10,
000, especially 1000 to 5000.

The method for producing (b1) is not particularly limited. For example, in the absence of an organic solvent; (a1), (a2) and (c1) are reacted simultaneously; (a1) and (a1) A method of further reacting (c1) after the reaction of a2) and the like can be mentioned, but any method can be used for production. The reaction temperature is usually 30 to 100 ° C, preferably 40 to 80 ° C. In the case of reacting, the equivalent amount of the isocyanate group of (a1) in the case of (b11) is preferably 0.5 to, based on the equivalent amount of the total active hydrogen groups of (a2) to (a4) and (c1). 0.9, preferably 0.6 to 0.9, and if 0.9 or less, free isocyanate is small and fine particles are easily obtained, and 0.5
If it is above, the viscosity of the product is not too high and it is easy to emulsify. Further, in the case of (b12), the equivalent of the isocyanate group of (a1) is 2 to 1.2, preferably 1.9 to 1.3, relative to the equivalent of the active hydrogen group of (a2),
The NCO content of the prepolymer is 2.0-7.0%.
Moreover, the equivalent of (c1) to the equivalent of residual NCO in the reaction of (c1) is preferably 0.8 to 1.2.

As (b2), the organic peroxide (benzoyl peroxide,
Unsaturated dicarboxylic acids (for example, maleic anhydride, itaconic anhydride, etc.) and epoxy group-containing unsaturated compounds (for example, glycidyl acrylate, glycidyl methacrylate) using lauroyl peroxide, etc. or inorganic peroxides (hydrogen peroxide, etc.) as catalysts. , Allyl glycidyl ether, etc.) and the like.

Examples of (b3) include the above-mentioned (p2).

Examples of (b4) include the reaction products of the above-mentioned (p5) and the terminal epoxy group of (p5) with the above-mentioned (p4).

Examples of (b5) include organic peroxides (benzoyl peroxide,
Unsaturated dicarboxylic acids (for example, maleic anhydride, itaconic anhydride, etc.) and epoxy group-containing unsaturated compounds (for example, glycidyl acrylate, glycidyl methacrylate) using lauroyl peroxide, etc. or inorganic peroxides (hydrogen peroxide, etc.) as catalysts. , Allyl glycidyl ether, etc.) and the like.

Examples of (b6) are dimer acid derived from vegetable oil unsaturated fatty acid (C16-18), fatty acid (C16-18) and polyalkylene polyamine (C4-8, amino C3-5). ) And the like.

(B7) is poly (n = 2 to 100)
Oxyalkylene (alkylene group having 2 to 4 carbon atoms) glycol mono (meth) acrylic acid ester [eg, EO
10 moles, 15 moles of PO, such as monomethacrylate of a random polymer].

Of these, preferred are (b1) to (b3) from the viewpoint of compatibility with (a), and particularly preferred are (b1) from the viewpoint of easy introduction of a reactive group.

The weight ratio of (b) / (a) in the mixture (A) in the present invention is preferably 0.01 to 0.
8, more preferably 0.05 to 0.5. 0.0
When it is 1 or more, the effect of diluting the mixture is obtained and the dispersibility of the mixture in water is good, and when it is 0.8 or less, the hydrophilicity of the mixture is not significantly lowered and an aqueous dispersion of fine particles is obtained.
The viscosity of (A) is 20 Pa · s or less, preferably 15 Pa · s or less, and more preferably 10 Pa · s or less at the emulsion dispersion temperature, for example, 90 ° C. When it is 20 Pa · s or less, the dispersibility in water during emulsification is excellent. In addition,
More preferably, it is 20 Pa · s or less at 60 to 80 ° C. As a method of lowering the viscosity of (A),
The viscosities of (a) and (b) are set within the above-mentioned preferable range
Examples include a method of setting the mixing ratio of (b) / (a) to the above-mentioned preferable range.

The method of mixing (a) and (b) is not particularly limited, and usually (a) and (b) are mixed at 30 to 80 ° C. in a mixing device equipped with a stirring device.

Examples of the aqueous medium include water alone and a mixed solvent of water and a hydrophilic organic solvent, and preferably water alone. In the case of the mixed solvent, the ratio of the hydrophilic organic solvent to the weight of the mixed solvent is preferably 0 to 10%, more preferably 0 to 3%, and particularly preferably 0 to 0.3%. Examples of the hydrophilic organic solvent include those having a solubility in 100 g of water of 10 g or more. Examples thereof include ketones (acetone, methyl ethyl ketone, etc.), esters (ethyl acetate, ethyl cellosolve acetate, etc.), ethers (dioxane, tetrahydro). Furan, etc., amides (dimethylformamide, dimethylacetamide, etc.), N-methylpyrrolidone, etc., as well as alcohols [monohydric alcohols (methanol, ethanol, n- and iso-propanol, n-, iso-, sec- And tert-butanol), and combinations thereof.

The method for emulsifying and dispersing the mixture (A) in the present invention in an aqueous medium is, for example, shearing in water in a container equipped with a stirring device (for example, a device having a propeller or a horizontal blade on a stirring shaft). While feeding (A) and emulsifying and dispersing, a batch method, (A) is pumped into a continuous kneader (high-speed rotary kneader having a rotor and a stator), and an aqueous medium is introduced in the kneader flow path. And a continuous method in which the mixture is fed by a pump and mixed.

Regarding the emulsifying and dispersing conditions of (A) and the aqueous medium, the temperature of (A) is usually 40 to 100 ° C, preferably 50 to 90 ° C. If it is 40 ° C. or higher, the viscosity is low and dispersion is easy, and if it is lower than 100 ° C., (a) is stable. The temperature of the aqueous medium is usually 10 to 60 ° C, preferably 20 to 50 ° C. When the temperature is 10 ° C or higher, emulsification and dispersion are easy, and when the temperature is lower than 60 ° C, the water elongation reaction is suppressed, which is preferable. The temperature of the aqueous dispersion obtained in the emulsification / dispersion step (A) is preferably 30 to 90 ° C., more preferably 60 to 90 ° C., and the side reaction (such as water elongation reaction) in (A) is the emulsion dispersion step. If it does not occur, it is preferable that the temperature be as close to 90 ° C as possible because the viscosity will be low.

In the aqueous dispersion (B) of the present invention, (A) is brought into contact with an aqueous medium for emulsification and dispersion, and then a chain extender (a4) and, if necessary, a terminating agent (a5) are added,
It can be obtained by further chain extension of (a) in (A) and, if necessary, stopping the reaction.

(A4) contains an aliphatic polyamine [alkylene (C2-8) diamine (for example, ethylenediamine: hereinafter abbreviated as EDA, containing at least two primary and / or secondary amino groups in the molecule) Hexamethylenediamine, etc.), poly (n = 2-10) alkylene (carbon number 2-6) poly (n = 3-11) amine (diethylenetriamine, triethylenetetramine, etc.)], alicyclic polyamine [4,4 ′] -Diaminodicyclohexylmethane, 1,4-diaminocyclohexane, isophoronediamine (hereinafter abbreviated as IPDA), etc., aliphatic polyamines having an aromatic ring (xylylenediamine, etc.), aromatic polyamines (4,4'-diaminodiphenylmethane, tri- Dilenamine, etc.) Hydrazine and hydrazine derivatives (HDH, carbodihydride Radide, adipic acid dihydrazide, etc.) and the like. Among these, preferred is a mixture of or, or because of the ease of controlling the molecular weight.

Examples of (a5) include aliphatic compounds (having 2 to 2 carbon atoms).
6) Monoamines (ethylamine, n-butylamine, diisopropylamine, di-n-butylamine, etc.) and lower (C1-4) monoalcohols (methanol, butanol, etc.) can be mentioned.

The amounts of (a4) and (a5) added are
In the case of (a4) with respect to (a), 0.3 to 0.8 equivalents to the isocyanate group equivalent of (a), (a5)
In the case of, it is 0 to 0.2 equivalent.

The dispersion obtained as described above and (a
4) There are no particular restrictions on the mixing method of [and optionally (a5)], but for example, the dispersion is fed into a disperser, and (a
4) A method of pumping and mixing the aqueous liquid of [and (a5)] if necessary, and bringing the dispersion into contact with the aqueous liquid of [a4] [and (a5) if necessary) at the inlet of the dispersing machine and feeding into the dispersing machine. Method of mixing A method in which the aqueous liquid of (a4) [and optionally (a5)] is pumped into the disperser and the dispersion is mixed in the middle of the flow path of the disperser, and the like can be mentioned, but or is preferred. .

The solid content concentration of the aqueous dispersion (B) in the present invention (percentage of the residue after heating and drying 1.5 g of the sample at 130 ° C. for 90 minutes to the weight before heating and drying) is preferably 35 to 55. %, More preferably 40 to 50%, and the polyurethane resin component in the solid content of (B) is preferably 60 to 90%, more preferably 70 to 90%.
And (b) is preferably 10 to 40%, more preferably 10 to 30%. The Mn of (B) is preferably 3000 to 200000, more preferably 50.
The viscosity of (B) at 25 ° C is 25 ° C, preferably 50 to 1000 Pa · s, and more preferably 50 to 500 Pa · s.

The aqueous dispersion (B) of the present invention is applied to a substrate as it is, and when the aqueous dispersion (B) is further added to (B) with a crosslinking agent and / or a crosslinking catalyst, a crosslinking agent-curable polyurethane. It may be applied as an aqueous resin dispersion (C). As the cross-linking agent, a water-dispersible cross-linking agent which reacts with the reactive group (b) such as carbohydrazide group, hydroxyl group, carboxyl group, radically polymerizable unsaturated group, glycidyl group and silyl group can be used. Compounds, carbodiimide compounds, aziridine compounds,
Examples thereof include oxazoline compounds, melamine-formaldehyde compounds and isocyanate compounds. Examples of epoxy compounds include glycidyl ethers obtained from polyhydric alcohol and epichlorohydrin (glycerin polyglycidyl ether, sorbitol polyglycidyl ether, bisphenol A diglycidyl ether, etc.). Examples of the carbodiimide compound include aromatic carbodiimide compounds and urea-modified carbodiimide compounds. Examples of the aziridine compound include urea-modified, tertiary amino group-modified and amide-modified aziridine compounds derived from ethyleneimine and polyisocyanate, vinyl ester, lower alcohol monoglycidyl ether, acid chloride and the like. Examples of the oxazoline-based compound include compounds obtained by subjecting the above amide-modified aziridine compound to thermal cyclization modification. Examples of the melamine-formaldehyde compound include alkyl group type, methylol group type and imino group type amino resins derived from melamine, formaldehyde and lower alcohols. And as the isocyanate compound, a water-dispersible isocyanate obtained by partially modifying polyisocyanate with an ethylene oxide polyadduct of monoalcohol, introducing a hydrophilic group into a blocked isocyanate compound, or using an emulsifier A dispersion or the like can be used. Further, as the crosslinking catalyst when (b) contains an unsaturated double bond, a metal dryer (metal octylate, metal naphthenate) or the like can be used. The addition amount of these crosslinking agent and crosslinking catalyst is preferably 0.1 to 10% with respect to the weight of (b) in the aqueous dispersion.

Aqueous dispersions (B) and (C) according to the invention
For water-based paints and coatings (corrosion-resistant coatings for metals, scratch-resistant coatings for metals and resins, water-resistant coatings for paper and leather, solvent-resistant and moisture-proof coatings, and floor polish coatings). Topcoat, undercoat, intermediate coating: The coating amount of these paints or coating agents is usually 5 to 100 g / m ² , and the thickness is 1 to 200.
μ), various binders (binders for automobile paints, binders for external wall coatings, binders for coated paper, and binders for ceramics, etc.), adhesives (woodworking adhesives, adhesives for metal parts, adhesives for plastics, electronic substrates) Adhesives, fabric adhesives, etc.), and fiber processing agents (pigment printing binders, non-woven fabric binders, and woven fabrics)
It can be used in a wide range of fields such as knitting fabric processing agents). In addition, room temperature drying and heat drying (preferably 40
˜180 ° C., 1 minute to 60 minutes).

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. The raw material symbols used in the examples are as follows. "PES-2000"; polyester diol consisting of 1,4-butanediol and neopentyl glycol / adipic acid (Mn2000, Sanyo Chemical Industries, San Ester 45620), "PP-2000"; polypropylene glycol (Mn
2000, Sanyo PP-200 manufactured by Sanyo Chemical Industries
0),

Production Example 1: 134 parts (1 mol) of DMPA, 2000 parts (1 mol) of "PES2000", and 666 parts (3 mol) of IPDI were charged into a stainless steel reactor equipped with an isocyanate group-containing prepolymer having an ionic group and stirred at 60 ° C. Was reacted for 8 hours to prepare a prepolymer (a-1) having a viscosity of 40 Pa · s / 90 ° C. and an NCO content of 3.0%.

Production Example 2: Ionic Group-Containing Isocyanate-Terminated Prepolymer In the same reactor as in Production Example 1, 134 parts (1 mol) of DHPS, 2000 parts (1 mol) of "PP2000", TDI were added.
522 parts (3 mol) were charged and reacted at 60 ° C. for 3 hours to produce a prepolymer (a-2) having a viscosity of 20 Pa · s / 90 ° C. and an NCO content of 3.0%.

Production Examples 3-8: Reactive Diluent In the same reactor as in Production Example 1, "PP2000" 200 was added.
0 part (1 mol) and 444 parts (2 mol) of IPDI were charged and reacted at 110 ° C. for 8 hours to synthesize a prepolymer having a terminal isocyanate group. Further, the type and amount of (c1) [activity] shown in Table 1 were used. A hydrogen group and a compound containing another reactive group] were reacted at 100 ° C. for 1 hour to obtain reactive diluents (b-1) to (b-6). The viscosity and Mn at 90 ° C. are shown in Table 1.

[0077]

[Table 1]

Production Examples 9 to 14: Production of Mixture (A) As shown in Table 2, 100 parts of (a-1) or (a-2) to (b)
25 parts of each of -1) to (b-6) were mixed at 90 ° C. to prepare mixtures (A-1) to (A-6). Their viscosities were measured with a rotary viscometer (B-type viscometer manufactured by Tokyo Keiki Co., Ltd., rotation speed 30 rpm). The results are shown in Table 2.

[0079]

[Table 2]

Examples 1 to 6 Water was charged into a stainless steel beaker in the number shown in Table 3, and 50
(A-1) of the number of parts shown in Table 3 which was adjusted to 90 ° C and adjusted to 90 ° C while stirring at 12,000 rpm with a TK homomixer.
(A-6) was added over 3 minutes, and the mixture was dispersed for another 3 minutes. Then, a 10% by weight aqueous solution of a stretching agent in the number shown in Table 3 was further added and mixed and dispersed for 1 minute to produce an aqueous dispersion of the present invention. The particle size of the obtained aqueous dispersion was measured by a light scattering type particle size distribution analyzer (“LA700”: manufactured by Horiba Ltd.). The nonvolatile content was measured by drying at 130 ° C. for 45 minutes. Viscosity is a rotary viscometer (B-type viscometer manufactured by Tokyo Keiki, rotation speed
60 rotations) and the results are shown in Table 3.

[0081]

[Table 3]

Comparative Examples 1 and 2; Prepolymer (a-1)
103.6 parts, 30 parts of IPDI as a diluent having an isocyanate group, or a liquid rosin-based tackifying resin as a diluent that is not reactive (manufactured by Arakawa Chemical Co., Ltd., trade name "KE-828" 20 parts, is mixed, An aqueous dispersion was prepared in the same manner as in Example 1 except that the charging ratio shown in Table 4 was used.

[0083]

[Table 4]

Examples 7 and 8 and Comparative Examples 3 and 4 (Change in appearance of dry film after hot water immersion and measurement of shear modulus at 60 ° C.) Aqueous dispersions of Examples 1 and 2 and Comparative Examples 1 and 2 Water-dispersible isocyanate crosslinking agent (Aquanate AQ-100; manufactured by Nippon Polyurethane Industry Co., Ltd.) was added to 100 parts.
Parts are mixed and polypropylene tray (8 cm x 20 c
m) was poured to a thickness of 500 nm, dried at room temperature for 24 hours, and further heat-treated at 80 ° C. for 1 hour to form a film. The obtained film was immersed in warm water at 40 ° C. for 24 hours and the appearance change was observed. Further, the shear elastic modulus at 60 ° C. of the coating was measured at a frequency of 10 Hz using a Vibron spectrometer (manufactured by Iwamoto Seisakusho). The results are shown in Table 5.

[0085]

[Table 5]

[0086]

The polyurethane resin aqueous dispersion of the present invention has the following effects as compared with the conventional ones. Very low organic solvent content, high safety to human body, and environmentally friendly. Low viscosity makes it easy to handle. It is an aqueous dispersion of fine particles and has high storage stability. A dry or cured film having excellent water resistance and physical properties can be obtained.

Continued front page    F-term (reference) 4J034 BA08 CA11 CA14 CA15 CA16                       CB03 CB04 CB05 CB07 CC03                       CC12 CC26 CC45 CC52 CC61                       CC62 CC65 CC67 CE03 DA01                       DA03 DA05 DA08 DB03 DB07                       DF00 DG00 DK00 DL01 DP12                       DP18 JA42 QC05 RA07 RA08                       RA09

Claims (11)

[Claims] 1. An isocyanate group-terminated prepolymer (a) containing an ionic group and / or an ion-forming group.
And a reactive diluent (b) having no isocyanate group are emulsified and dispersed in an aqueous medium to obtain an aqueous dispersion, which is then mixed with an extender to chain-extend (a) to obtain a polyurethane resin aqueous solution. A method for producing a dispersion (B), wherein the reactivity of the reactive group of (b) with the isocyanate group is lower than the reactivity of the secondary amino group with the isocyanate group, and (B) is 0.1-10 Pa
A method for producing a polyurethane resin aqueous dispersion, which has a viscosity of s. 2. The production method according to claim 1, wherein the emulsifying dispersion is carried out at a temperature of 60 to 90 ° C. 3. (b) is a polyurethane-based reactive diluent (b1), a polyether-based reactive diluent (b2), a polyester-based reactive diluent (b3), an epoxy-based reactive diluent (b4), Polyolefin reactive diluent (b
5), one or more reactive diluents at 25 ° C. selected from the group consisting of a polyamide-based reactive diluent (b6) and a poly (meth) acrylate-based reactive diluent (b7). Or the production method described in 2. 4. (b) is a carbohydrazide group, a hydroxyl group,
The method according to any one of claims 1 to 3, which has at least one reactive group selected from the group consisting of a carboxyl group, a radically polymerizable unsaturated group, a glycidyl group and a silyl group. 5. The method for producing an aqueous dispersion according to claim 1, wherein (b) has a number average molecular weight of 500 to 10,000. 6. (b) is an organic polyisocyanate and 30
The method according to any one of claims 1 to 5, which is a polyurethane-based reactive diluent derived from a polymer polyol that is liquid at ° C. 7. The weight ratio of (b) / (a) is from 0.05 to.
It is 0.5, The manufacturing method in any one of Claims 1-6. 8. The aqueous medium is water or a mixed solvent of water and an organic solvent, and the amount of the organic solvent is 0.3% or less based on the weight of the mixed solvent. The manufacturing method described. 9. A polyurethane resin aqueous dispersion obtained by the method for producing an aqueous dispersion according to claim 1. 10. A curable polyurethane resin aqueous dispersion (C), wherein a crosslinking agent is further added to the aqueous dispersion according to claim 9. 11. A polyurethane resin molded product obtained by applying the aqueous dispersion according to claim 9 or 10 to a substrate and drying or curing at room temperature or under heating.