JP5545954B2 - Water-based polyurethane resin, paint film, artificial or synthetic leather - Google Patents

Description

The present invention relates to an aqueous polyurethane resin, a coating film obtained from the aqueous polyurethane resin, and an artificial or synthetic leather in which the aqueous polyurethane resin is used.

In recent years, water-based resins are spreading from the viewpoints of environmental conservation, resource saving, safety, etc., among which water-based polyurethane resins are used from the viewpoint of durability, chemical resistance, and wear resistance, Widely used in fields such as binders and coating agents.
However, when an aqueous polyurethane resin is subjected to a coating process at a high speed, it may not withstand the shearing force generated in the process and may generate aggregates. Therefore, an aqueous polyurethane resin excellent in dispersion stability that can stably disperse even under high shearing force and suppress the generation of aggregates is desired.

In general, a coating film obtained from a water-based polyurethane resin has a lower water resistance due to water and a heat resistance and durability than a coating film obtained from a solvent-type polyurethane resin. Further improvements are desired.
With respect to the above needs, for example, (A) (i) a polyisocyanate, (ii) a high molecular weight active hydrogen-containing material; and (iii) a prepolymer comprising a hydrophilic alkylene oxide polyol or polyamine; (B) water; and (C ) In some cases, an aqueous polyurethane dispersion comprising a chain extender and / or surfactant reaction product, wherein the amount of reaction product in the dispersion is 40-60% by weight Liquids have been proposed (see, for example, Patent Document 1 below), and preferred polyisocyanates include 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane or mixtures thereof. Are listed.
JP 2006-509863A

However, even the aqueous polyurethane resin described in Patent Document 1 is still insufficient in dispersion stability and heat resistance, and further improvement of these is desired. Moreover, the coating film obtained from this water-based polyurethane resin has a problem that tack (stickiness) occurs.
An object of the present invention is to provide an aqueous polyurethane resin which is excellent in dispersion stability, solvent resistance and heat resistance and can realize an excellent texture, and a coating film obtained from the aqueous polyurethane resin, Is to provide artificial or synthetic leather in which the aqueous polyurethane resin is used.

  In order to achieve the above object, the aqueous polyurethane resin of the present invention contains 1,4-bis (isocyanatomethyl) cyclohexane isocyanate groups in a proportion of 50 mol% or more with respect to the total number of moles of isocyanate groups. It is characterized by being obtained by a reaction between an isocyanate group-terminated prepolymer obtained by reacting at least a polyisocyanate, a high molecular weight polyol, and an active hydrogen compound containing a hydrophilic group with a chain extender.

In the aqueous polyurethane resin of the present invention, it is preferable that the chain extender contains an active hydrogen compound containing an alkoxysilyl group.
The aqueous polyurethane resin of the present invention preferably contains 0.05 to 1.5% by mass of Si atoms.
In the aqueous polyurethane resin of the present invention, it is preferable that the chain extender is a compound represented by the following general formula (1).
General formula (1):

(In the formula, R1 and R2 are the same or different and each represent an alkyl group having 1 to 4 carbon atoms. R3 and R4 are the same or different and each represent an alkylene group having 1 to 4 carbon atoms. Represents an integer of ~ 3.)
In the aqueous polyurethane resin of the present invention, it is preferable that 1,4-bis (isocyanatomethyl) cyclohexane contains at least 50% by mass of trans-1,4-bis (isocyanatomethyl) cyclohexane.

Moreover, the coating film of this invention is obtained from the said water-based polyurethane resin, It is characterized by the above-mentioned.
Furthermore, the artificial or synthetic leather of the present invention is characterized in that the above-mentioned aqueous polyurethane resin is used.

According to the aqueous polyurethane resin of the present invention, it is possible to improve dispersion stability, solvent resistance and heat resistance, and it is possible to achieve an excellent texture. Therefore, it is possible to provide the coating film, artificial or synthetic leather of the present invention that makes use of these characteristics.

Embodiment of the Invention

The aqueous polyurethane resin of the present invention is obtained by a reaction between an isocyanate group-terminated prepolymer and a chain extender.
The isocyanate group-terminated prepolymer can be obtained by reacting at least a polyisocyanate, a high molecular weight polyol, and an active hydrogen compound containing a hydrophilic group.
In the present invention, the polyisocyanate has an isocyanate group of 1,4-bis (isocyanatomethyl) cyclohexane in an amount of 50 mol% or more, preferably 70 mol% or more, more preferably, based on the total number of moles of isocyanate groups. 80 mol% or more, particularly preferably 90 mol%. Most preferably, it contains 100 mol%.

  1,4-bis (isocyanatomethyl) cyclohexane includes cis-1,4-bis (isocyanatomethyl) cyclohexane (hereinafter referred to as cis 1,4 isomer) and trans-1,4-bis ( There are stereoisomers of isocyanatomethyl) cyclohexane (hereinafter referred to as trans 1,4), and in the present invention, 1,4-bis (isocyanatomethyl) cyclohexane is preferably trans 1,4, , 50% by mass or more, more preferably 70% by mass, particularly preferably 80% by mass or more. Most preferably, the content is 90% by mass.

1,4-bis (isocyanatomethyl) cyclohexane is, for example, a two-stage method (direct method) or a salt formation method described in JP-A-7-309827, or Japanese Patent Application Laid-Open No. 2004-244349. It can be produced by a method that does not use phosgene described in Japanese Unexamined Patent Publication No. 2003-212835.
Examples of the polyisocyanate that can be used in combination with 1,4-bis (isocyanatomethyl) cyclohexane in the above polyisocyanate include 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3 -Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 1,3-bis ( Isocyanatomethyl) cyclohexane, 1,3-bis (isocyanatoethyl) cyclohexane, 1,4-bis (isocyanatoethyl) cyclohexane, 2,5- or 2,6-bis (isocyanate) Tomechiru) include alicyclic diisocyanates such as norbornane and mixtures thereof. Also, for example, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2, Aliphatic diisocyanates such as 4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methylcaproate. Further, isocyanurates, allophanates, burettes, oxadiazine triones and uretdione modified products of these polyisocyanates can be used in combination as long as the film forming property of the aqueous polyurethane resin is not impaired.

  Furthermore, monoisocyanate can be used in combination as long as the dispersion stability, solvent resistance, heat resistance and texture of the aqueous polyurethane resin are not impaired. Examples of the monoisocyanate include methyl isocyanate, ethyl isocyanate, n-hexyl isocyanate, cyclohexyl isocyanate, 2-ethylhexyl isocyanate, phenyl isocyanate, and benzyl isocyanate.

  The polyisocyanate that can be used in combination with 1,4-bis (isocyanatomethyl) cyclohexane is preferably 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (also known as isophorone diisocyanate (IPDI)), 4,4 '-Methylenebis (cyclohexyl isocyanate), 1,4-cyclohexane diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, 2,5- or 2,6-bis (isocyanatomethyl) norbornane and mixtures thereof, hexamethylene diisocyanate As well as the above-mentioned modified products of these polyisocyanates.

  In addition, 1,3-bis (isocyanatomethyl) cyclohexane includes cis-1,3-bis (isocyanatomethyl) cyclohexane (hereinafter referred to as cis 1,3 form), and trans-1,3- There is a stereoisomer of bis (isocyanatomethyl) cyclohexane (hereinafter referred to as trans 1,3), and 1,3-bis (isocyanatomethyl) cyclohexane and 1,4-bis (isocyanatomethyl) cyclohexane When used in combination, 1,3-bis (isocyanatomethyl) cyclohexane is trans 1,3, preferably 50% by mass or more, more preferably 70% by mass, particularly preferably 90% by mass or more. contains.

In the present invention, the high molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight of 400 or more, and examples thereof include polyether polyol, polyester polyol, and polycarbonate polyol.
The number average molecular weight of high molecular weight polyol is 400-5000, for example, Preferably, it is 1400-3000, More preferably, it is 1500-2500, The hydroxyl value is 10-125 mgKOH / g, for example.

Examples of the polyether polyol include polypropylene glycol and polytetramethylene ether glycol. Polypropylene glycol is preferably a polyoxyalkylene polyol having a small amount of by-product of monool using a phosphazenium compound described in Japanese Patent No. 3905638 as a catalyst.
Polypropylene glycol is, for example, an addition polymer of propylene oxide mainly using a low molecular weight polyol or low molecular weight polyamine as an initiator, and ethylene oxide is used in combination as needed (that is, random propylene oxide and ethylene oxide) And / or a block copolymer).

  The low molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight of less than 60 to 400, and includes ethylene glycol, propanediol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2- Butylene glycol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, alkane (7-22) diol, diethylene glycol, triethylene glycol, dipropylene glycol, 1,3- or 1, 4-cyclohexanedimethanol and mixtures thereof, 1,4-cyclohexanediol, alkane-1,2-diol (C17-20), hydrogenated bisphenol A, 1,4-dihydroxy-2-butene, 2,6-dimethyl -1-Octene-3,8-diol, bisph Dihydric alcohols such as Nord A, for example, trihydric alcohols such as glycerin and trimethylolpropane, such as tetramethylolmethane, pentaerythritol, dipentaerythritol, D-sorbitol, xylitol, D-mannitol, D-mannitol, etc. Examples thereof include polyhydric alcohols having 4 or more hydroxyl groups.

Examples of the low molecular weight polyamine include aliphatic diamines such as ethylenediamine, and aromatic diamines such as tolylenediamine.
Examples of the polytetramethylene ether glycol include a ring-opening polymer obtained by cationic polymerization of tetrahydrofuran, and amorphous polytetramethylene ether glycol obtained by copolymerizing the above-described dihydric alcohol with a polymerization unit of tetrahydrofuran.

Examples of the polyester polyol include polycondensates obtained by reacting the above-described polyhydric alcohol and polybasic acid under known conditions.
Examples of the polybasic acid include oxalic acid, malonic acid, succinic acid, methyl succinic acid, glutaric acid, adipic acid, 1,1-dimethyl-1,3-dicarboxypropane, and 3-methyl-3-ethylglutaric acid. , Azelaic acid, sebacic acid, other aliphatic dicarboxylic acids (carbon number 11-13), suberic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, octadecanedioic acid, nonadecanedioic acid Acid, eicosane diacid, methylhexane diacid, citraconic acid, hydrogenated dimer acid, maleic acid, fumaric acid, itaconic acid, orthophthalic acid, isophthalic acid, terephthalic acid, toluene dicarboxylic acid, dimer acid, het acid, pimelic acid, Carboxylic acids such as acid anhydrides, acid halides, Maleic acid, such as 12-hydroxy stearic acid.

Further, as the polyester polyol, for example, polycaprolactone polyol, polyvalerolactone polyol obtained by ring-opening polymerization of lactones such as ε-caprolactone and γ-valerolactone using the above dihydric alcohol as an initiator, Furthermore, the lactone type | system | group polyol which copolymerized said dihydric alcohol to them etc. are mentioned.
Examples of the polycarbonate polyol include a ring-opening polymer of ethylene carbonate using the above dihydric alcohol as an initiator, and examples thereof include 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1 Non-crystalline polycarbonate polyol obtained by copolymerizing a dihydric alcohol such as 1,6-hexanediol and a ring-opening polymer.

These high molecular weight polyols can be used alone or in combination of two or more. Of these, polycarbonate polyols are preferable, polycarbonate diols are more preferable, and amorphous (room temperature liquid) polycarbonate diols are particularly preferable.
In the present invention, the active hydrogen compound containing a hydrophilic group is a compound having both a hydrophilic group and an active hydrogen group, and examples of the hydrophilic group include an anionic group, a cationic group, and a nonionic group. . The active hydrogen group is a group that reacts with an isocyanate group, and examples thereof include a hydroxyl group, an amino group, a carboxyl group, and an epoxy group. More specifically, as the active hydrogen compound containing a hydrophilic group, a carboxylic acid group-containing active hydrogen compound, a sulfonic acid group-containing active hydrogen compound, a hydroxyl group-containing active hydrogen compound, a hydrophilic group-containing polybasic acid, a polyoxyethylene group-containing An active hydrogen compound is mentioned.

  Examples of the carboxylic acid group-containing active hydrogen compound include 2,2-dimethylolacetic acid, 2,2-dimethylollactic acid, 2,2-dimethylolpropionic acid (hereinafter abbreviated as DMPA), and 2,2-dimethylol. Dihydroxycarboxylic acids such as butanoic acid (hereinafter abbreviated as DMBA), 2,2-dimethylolbutyric acid, 2,2-dimethylolvaleric acid, for example, diaminocarboxylic acids such as lysine and arginine, or metal salts thereof And ammonium salts. Preferably, 2,2-dimethylolpropionic acid (DMPA) and 2,2-dimethylolbutanoic acid (DMBA) are mentioned.

  Examples of the sulfonic acid group-containing active hydrogen compound include dihydroxybutanesulfonic acid and dihydroxypropanesulfonic acid obtained from a synthesis reaction of an epoxy group-containing compound and acidic sulfite. Further, for example, N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonic acid, N, N-bis (2-hydroxyethyl) -2-aminobutanesulfonic acid, 1,3-phenylenediamine-4 , 6-disulfonic acid, diaminobutanesulfonic acid, diaminopropanesulfonic acid, 3,6-diamino-2-toluenesulfonic acid, 2,4-diamino-5-toluenesulfonic acid, N- (2-aminoethyl) -2 -Aminoethanesulfonic acid, 2-aminoethanesulfonic acid, N- (2-aminoethyl) -2-aminobutanesulfonic acid, or metal salts or ammonium salts of these sulfonic acids.

Examples of the hydroxyl group-containing active hydrogen compound include N- (2-aminoethyl) ethanolamine.
Examples of the hydrophilic group-containing polybasic acid include polybasic acids containing sulfonic acid, more specifically, 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, and 5- (p-sulfophenoxy) isophthalic acid. Acid, 5- (sulfopropoxy) isophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, sulfopropylmalonic acid, sulfosuccinic acid, 2-sulfobenzoic acid, 2,3-sulfobenzoic acid, 5-sulfosalicylic acid, In addition, alkyl esters of these carboxylic acids, and metal salts and ammonium salts of these sulfonic acids are also included. Preferably, the sodium salt of 5-sulfoisophthalic acid and the sodium salt of dimethyl 5-sulfoisophthalic acid are used.

The polyoxyethylene group-containing active hydrogen compound is a compound having a polyoxyethylene group in the main chain or side chain and having two or more active hydrogen groups.
Examples of the polyoxyethylene group-containing compound include polyethylene glycol (for example, number average molecular weight 200 to 6000, preferably 300 to 3000) and polyoxyethylene side chain-containing polyol.

The polyoxyethylene side chain-containing polyol is a compound having a polyoxyethylene group in the side chain and having two or more active hydrogen groups, and can be synthesized as follows.
That is, first, the above-mentioned diisocyanate and one-end-capped polyoxyethylene glycol (for example, alkoxyethylene glycol whose one-end is blocked with an alkyl group having 1 to 4 carbon atoms, having a number average molecular weight of 200 to 6000, preferably 300 to 3000) is subjected to a urethanation reaction in an excess ratio of the isocyanate group of the diisocyanate with respect to the hydroxyl group of the one-end-capped polyoxyethylene glycol, and if necessary, the unreacted diisocyanate is removed, thereby containing a polyoxyethylene chain. Monoisocyanate is obtained.

Next, polyoxyethylene chain-containing monoisocyanate and dialkanolamine (for example, diethanolamine) are approximately equal in amount of the isocyanate group of polyoxyethylene group-containing monoisocyanate with respect to the secondary amino group of dialkanolamine. The urea reaction is carried out at a rate of
As a diisocyanate for obtaining a polyoxyethylene side chain-containing polyol, an aliphatic diisocyanate such as hexamethylene diisocyanate (HDI), 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane (H ₆ XDI) is preferable. Or a mixture thereof, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (also known as isophorone diisocyanate (IPDI)), 4,4′-methylenebis (cyclohexyl isocyanate) (H ₁₂ MDI), 2,5 -Or alicyclic diisocyanates such as 2,6-bis (isocyanatomethyl) norbonane (NBDI) or mixtures thereof. More preferably, HDI is mentioned.

In addition, when a polyoxyethylene group containing compound is mix | blended, the content with respect to the water-based polyurethane resin (solid content) of a polyoxyethylene group is 0.9-30 mass%, for example, Preferably, 2-20 It is 2 mass%, More preferably, it is 2-10 mass%.
These active hydrogen compounds containing a hydrophilic group can be used alone or in combination of two or more. Of these, carboxylic acid group-containing active hydrogen compounds and polyoxyethylene group-containing active hydrogen compounds are preferable.

In order to obtain an isocyanate group-terminated prepolymer, for example, a polyisocyanate, a high molecular weight polyol, and an active hydrogen compound containing a hydrophilic group are reacted by a known polymerization method such as bulk polymerization or solution polymerization.
If an active hydrogen compound containing a hydrophilic group is contained in a high molecular weight polyol, the high molecular weight polyol and polyisocyanate can be reacted to obtain an isocyanate group-terminated prepolymer.

For example, in the synthesis of the polyester polyol described above, an active hydrogen compound containing a hydrophilic group can be added to the high molecular weight polyol by blending the active hydrogen compound containing the hydrophilic group described above as a polyhydric alcohol. .
For example, in the synthesis | combination of the above-mentioned polyester polyol, the active hydrogen compound containing a hydrophilic group can also be contained in a high molecular weight polyol by mix | blending a hydrophilic group containing polybasic acid as a polybasic acid.

In addition, for example, in the synthesis of polyester polyol, polyether polyol, polycarbonate polyol, epoxy polyol obtained by ring-opening polymerization, by blending an active hydrogen compound containing the above hydrophilic group as an initiator or a copolymerization component, An active hydrogen compound containing a hydrophilic group can be contained in the high molecular weight polyol.
Furthermore, the high molecular weight polyol contains a hydrophilic group by reacting an active hydrogen compound containing a hydrophilic group with a high molecular weight polyol such as polyether polyol (preferably polytetramethylene ether glycol). An active hydrogen compound can be contained.

And each said component is active hydrogen group (a hydroxyl group, an amino group, etc.) of the active hydrogen compound containing a high molecular weight polyol and a hydrophilic group (When the low molecular weight polyol mentioned later is mix | blended, the hydroxyl group of the low molecular weight polyol is changed. The equivalent ratio of the isocyanate group of the polyisocyanate (isocyanate group / active hydrogen group) is, for example, 1.1 to 2.5,
Preferably, it is formulated so as to have a ratio of 1.2 to 2.3, more preferably 1.2 to 2.
Mixed). If the equivalent ratio of isocyanate groups is within this range, the dispersion stability of the aqueous polyurethane resin can be improved. Therefore, using this aqueous polyurethane resin,
A coating film, artificial leather, or synthetic leather excellent in texture can be obtained.

In bulk polymerization, for example, while stirring a polyisocyanate under a nitrogen stream, an active hydrogen compound containing a high molecular weight polyol and a hydrophilic group is added thereto to a reaction temperature of 50 to 130 ° C., more preferably 50 to 80. The reaction is carried out at 3 ° C for about 3 to 15 hours.
In solution polymerization, a polyisocyanate, a high molecular weight polyol, and an active hydrogen compound containing a hydrophilic group are added to an organic solvent, and the reaction temperature is 50 to 120 ° C., more preferably 50 to 80 ° C., for about 3 to 15 hours. React.

  Examples of the organic solvent are low-boiling solvents that are inert to isocyanate groups, rich in hydrophilicity, and easy to remove. For example, ketones such as acetone and methyl ethyl ketone, ethers such as tetrahydrofuran, methyl Cellosolve acetates such as cellosolve acetate and ethyl cellosolve acetate, for example, carbitol acetates such as methyl carbitol acetate and ethyl carbitol acetate, for example, nitriles such as acetonitrile, esters such as ethyl acetate and butyl acetate, etc. It is done.

Further, in the above polymerization reaction, the above-described low molecular weight polyol can be appropriately blended according to the purpose and application.
Furthermore, in the above polymerization reaction, for example, a known urethanization catalyst such as an amine-based, tin-based, lead-based, or bismuth-based catalyst may be added, and from the resulting isocyanate group-terminated prepolymer. Free (unreacted) polyisocyanate may be removed by a known removal means such as distillation or extraction.

In the obtained isocyanate group-terminated prepolymer, when an anionic group or a cationic group is contained as a hydrophilic group, preferably, a neutralizing agent is added to the anionic group or cationic group. A salt is formed.
For example, when an anionic group is contained, the neutralizing agent may be a conventional base such as an organic base [for example, tertiary amines (triC1-4 alkylamines such as trimethylamine and triethylamine, dimethyl Ethanolamine, methyldiethanolamine, triethanolamine, alkanolamines such as triisopropanolamine, heterocyclic amines such as morpholine)], inorganic bases [ammonia, alkali metal hydroxides (lithium hydroxide, sodium hydroxide, hydroxide) Potassium, etc.), alkaline earth metal hydroxides (magnesium hydroxide, calcium hydroxide, etc.), alkali metal carbonates (sodium carbonate, potassium carbonate, etc.)]. These bases can be used alone or in combination of two or more.

The neutralizing agent is added at a ratio of 0.4 to 1.2 equivalents, preferably 0.6 to 1 equivalent, per equivalent of anionic group.
The isocyanate group-terminated prepolymer thus obtained is a polyurethane prepolymer having two or more free isocyanate groups at its molecular ends, and the isocyanate group content (isocyanate group content) is, for example, It is 0.3-10 mass%, Preferably, it is 0.5-6 mass%, More preferably, it is 1.0-5.0 mass%. Moreover, the average functional group number of an isocyanate group is 1.5-3.0, for example, Preferably, it is 1.9-2.5. In addition, the number average molecular weight (number average molecular weight by GPC measurement using standard polystyrene as a calibration curve) is, for example, 1000 to 30000, preferably 1500 to 20000. The hydrophilic group concentration of the isocyanate group-terminated prepolymer is, for example, 0.1 to 1.0 mmol / g, preferably 0.2 to 0.7 mmol / g, and more preferably 0.2 to 0.6 mmol / g. g.

In order to obtain the aqueous polyurethane resin of the present invention, the isocyanate group-terminated prepolymer obtained above is then reacted with a chain extender.
In the present invention, examples of the chain extender include low molecular weight polyols, polyamines, amino alcohols and the like.
Examples of the low molecular weight polyol include the low molecular weight polyol described above.

  Polyamines include, for example, aromatic polyamines such as 4,4′-diphenylmethanediamine, araliphatic polyamines such as 1,3- or 1,4-xylylenediamine or mixtures thereof, such as 3-aminomethyl- 3,5,5-trimethylcyclohexylamine (common name: isophoronediamine), 4,4'-dicyclohexylmethanediamine, 2,5 (2,6) -bis (aminomethyl) bicyclo [2.2.1] heptane, Alicyclic polyamines such as 1,3- or 1,4-bis (aminomethyl) cyclohexane or mixtures thereof, 1,3- or 1,4-cyclohexanediamine or mixtures thereof, such as ethylenediamine, 1,3- Propanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, Rajin (including hydrates.), Diethylenetriamine, triethylenetetramine, and aliphatic polyamines such as tetraethylene pentamine and the like.

Moreover, as amino alcohol, N- (2-aminoethyl) ethanolamine etc. are mentioned, for example.
Examples of the chain extender include active hydrogen compounds containing an alkoxysilyl group. An active hydrogen compound containing an alkoxysilyl group is a compound having both an alkoxysilyl group and an active hydrogen group.

  In the alkoxysilyl group, examples of the alkoxy group bonded to the Si atom include an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, an isopropoxy group, and an isobutoxy group. Preferably, a methoxy group and an ethoxy group are mentioned. The number of bonds of the alkoxy group to the Si atom is usually 1 to 3, preferably 1 to 2.

The active hydrogen group is an active hydrogen group that reacts with an isocyanate group, and examples thereof include an amino group and a hydroxyl group, and an amino group is preferable.
As such an active hydrogen compound containing an alkoxysilyl group, for example, it is represented by the following general formula (1).
General formula (1):

(In the formula, R1 and R2 are the same or different and each represent an alkyl group having 1 to 4 carbon atoms. R3 and R4 are the same or different and each represent an alkylene group having 1 to 4 carbon atoms. Represents an integer of ~ 3.)
In the general formula (1), examples of R1 and R2 include alkyl groups having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, and a butyl group. Moreover, as R3 and R4, C1-C4 alkylene groups, such as a methylene group, ethylene group, a propylene group, a butylene group, are mentioned, for example.

  More specifically, examples of the active hydrogen compound containing an alkoxysilyl group include N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethyl. Methoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropyldimethoxysilane, γ- (2-aminoethyl) aminopropyldiethoxysilane, γ-aminopropyltrimethoxy Examples thereof include silane, γ-aminopropyltriethoxysilane, γ-aminopropyldimethoxysilane, γ-aminopropyldiethoxysilane, N, N′-bis [γ- (trimethoxysilyl) propyl] ethylenediamine, and the like. Preferably, N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane is used.

The concentration of the active hydrogen group contained in the chain extender is preferably 250 to 800 mgKOH / g, and more preferably 350 to 600 mgKOH / g. If the concentration of the active hydrogen group is within this range, an aqueous polyurethane resin having excellent durability can be obtained.
These chain extenders can be used alone or in combination of two or more. Of these, the combined use of a polyamine and an active hydrogen compound containing an alkoxysilyl group is preferable.

And in order to obtain the aqueous polyurethane resin of this invention, the isocyanate group terminal prepolymer obtained by the above and a chain extender are made to react and disperse | distribute in water. As a result, an aqueous polyurethane resin in which the isocyanate group-terminated prepolymer is chain-extended with a chain extender can be obtained as an aqueous dispersion (dispersion).
In order to react the isocyanate group-terminated prepolymer and the chain extender in water, for example, first, the isocyanate group-terminated prepolymer is added to water to disperse the isocyanate group-terminated prepolymer. Next, a chain extender is added thereto to chain extend the isocyanate group-terminated prepolymer.

In order to disperse the isocyanate group-terminated prepolymer, the isocyanate group-terminated prepolymer is gradually added to water with stirring. Water is preferably added so as to have a ratio of 60 to 1000 parts by mass with respect to 100 parts by mass of the isocyanate group-terminated prepolymer.
Then, the chain extender is added to the isocyanate group-terminated prepolymer dispersed in water, and under stirring, the equivalent ratio of the active hydrogen groups (hydroxyl groups, amino groups, etc.) of the chain extender to the isocyanate groups of the isocyanate group-terminated prepolymer (active hydrogen groups) / Isocyanate group) is, for example, 0.5 to 1.1, preferably 0.7 to 1.

  Further, when a diamine (including a diamine containing an alkoxysilyl group) is used as a chain extender, the amino group is highly reactive with the isocyanate group of the isocyanate group-terminated prepolymer, and is also generated by the reaction. Since the urea bond has very high intermolecular cohesion, it is necessary to reduce the local reaction between the chain extender and the isocyanate monomer. Therefore, the chain extender is preferably formulated as an aqueous solution or a solution. The concentration of the diamine in the aqueous solution or solution is preferably at least 20% by mass, more preferably at least 50% by mass. Further, the chain extender is preferably added at a temperature of 40 ° C. or lower, and after the addition is completed, the reaction is completed, for example, at room temperature with further stirring.

In addition, when the isocyanate group terminal prepolymer is obtained by solution polymerization, after completion | finish of reaction of an isocyanate group terminal prepolymer, an organic solvent is removed by heating at appropriate temperature, for example under pressure reduction.
The aqueous dispersion of the aqueous polyurethane resin thus obtained is prepared such that the solid content is, for example, 10 to 70% by mass, preferably 20 to 50% by mass.

  The aqueous polyurethane resin has a number average molecular weight (number average molecular weight by GPC measurement using standard polystyrene as a calibration curve) of, for example, 3,000 to 100,000, preferably 5,000 to 80,000. is there. Moreover, as for aqueous polyurethane resin (solid content), the preparation ratio of the urethane group with respect to the urea group is 0.05-1.2, for example, More preferably, it is 0.1-0.8.

  When an active hydrogen compound containing an alkoxysilyl group is used as the chain extender, the aqueous polyurethane resin has a Si atom content of, for example, 0.05 to 1.5% by mass, preferably Is 0.05 to 1.2 mass%, more preferably 0.07 to 0.8 mass%. From the polyisocyanate containing the isocyanate group of 1,4-bis (isocyanatomethyl) cyclohexane in a proportion of 50 mol% or more with respect to the total number of moles of the isocyanate group, if the Si atom content is in the above range. There are advantages such as improvement in mechanical stability of the resulting aqueous polyurethane resin, and obtaining a coating film having increased solvent resistance and softening temperature.

  As a method for measuring the content of Si atoms, for example, a method of measuring the solid high-resolution NMR of a film after removing water contained in the aqueous polyurethane resin and producing a film in which the aqueous polyurethane resin is used, The organic component is completely decomposed by a wet ashing method (described later in [Example] below), and then measured by an atomic absorption method, an ICP emission method, a fluorescent X-ray method, or the like. Of these, an ICP emission analysis method is preferable.

In addition, the aqueous polyurethane resin has, for example, a mechanical stability of 200 μg / g or less, preferably 180 μg / g or less, more preferably 160 μg / g or less, according to a Maron test (described later in [Example] below). .
And if the water-based polyurethane resin of this invention is formed into a film, the coating film which is excellent in dispersion stability, solvent resistance, heat resistance, and also a texture can be obtained. Therefore, the aqueous polyurethane resin of the present invention can be suitably used for artificial leather or synthetic leather that takes advantage of the above characteristics.

For film formation, for example, an aqueous polyurethane resin is applied to a substrate by a known coating method such as a gravure coating method, a reverse coating method, a roll coating method, a bar coating method, a spray coating method, an air knife coating method, or a dipping method. And then dried by heating.
When the aqueous polyurethane resin of the present invention is used for production of artificial leather or synthetic leather, it can be used, for example, as a raw material for a wet method or a dry method.

The water-based polyurethane resin of the present invention is not limited to artificial leather or synthetic leather as described above, and can be used for various applications such as automobiles, electronic devices, clothing, medical care, building materials, paints, and adhesives. .

Next, although this invention is demonstrated based on a manufacture example, a synthesis example, an Example, and a comparative example, this invention is not limited by the following Example. In the following description, “part” and “%” are based on mass unless otherwise specified. Moreover, the measuring method used for a synthesis example etc. is shown below.
(Hydrophilic group concentration of isocyanate group-terminated prepolymer / unit: mmol / g)
The hydrophilic group concentration of the isocyanate group-terminated prepolymer was determined by a neutralization titration method using a potentiometric titrator (manufactured by Hiranuma Sangyo Co., Ltd., model: COM-980).

More specifically, about 1.5 g of the prepolymer solution before adding TEA was weighed and dissolved in 40 ml of a toluene / ethanol mixed solvent (toluene / ethanol volume ratio 2/1) prepared in advance. Subsequently, potentiometric titration using 0.1 mol / L ethanolic potassium hydroxide (titer for titration with titer) was performed, and the hydrophilic group concentration was measured.
In the hydrophilic group concentration, the hydrophilic group corresponds to the carboxyl group in the isocyanate group-terminated prepolymer.

Since the measured sample was an acetonitrile solution of the prepolymer, the prepolymer mass was corrected based on the amount of the charged solvent, and the hydrophilic group concentration of the prepolymer was calculated from the measured value.
(Oxyethylene group concentration of isocyanate group-terminated prepolymer / unit: mass%)
A fixed amount of tetrachloroethane dissolved in deuterated chloroform as an internal standard substance was added to 0.5 g of the isocyanate-terminated prepolymer, and deuterated chloroform was further added to make the total volume 5 mL. The oxyethylene group concentration was determined by ¹ H-NMR measurement (manufactured by JEOL, JNM-AL400) of this solution.
(Isocyanate group content / unit: mass% contained in the isocyanate group-terminated prepolymer solution)
The isocyanate group content of the isocyanate group-terminated prepolymer solution was measured by an n-dibutylamine method according to JIS K-1556 using a potentiometric titrator.

Production Example 1 (Method for producing 1,4-bis (isocyanatomethyl) cyclohexane)
Using a 1,4-bis (aminomethyl) cyclohexane (produced by Mitsubishi Gas Chemical Co., Inc.) having a trans / cis ratio of 93/7 by ¹³ C-NMR measurement as a raw material, a cold two-stage phosgenation method was carried out under normal pressure.
That is, a stirring bar, a thermometer, a phosgene introduction tube, a dropping funnel and a cooling tube were attached to the flask, and 400 parts by mass of orthodichlorobenzene was charged into the flask. While cooling the flask with cold water, the temperature in the flask was set to 10 ° C. or less, and 280 parts by mass of phosgene was introduced from the phosgene introduction tube. A dropping funnel was charged with a mixed liquid of 100 parts by mass of 1,4-bis (aminomethyl) cyclohexane and 500 parts by mass of orthodichlorobenzene, and the mixed liquid was added into the flask over 30 minutes. During this time, the temperature in the flask was maintained at 30 ° C. or lower. After completion of the addition, the inside of the flask became a white slurry liquid. Again, the reaction temperature was raised to 150 ° C. while introducing phosgene, and the reaction was continued at 150 ° C. for 5 hours. The reaction liquid in the flask became a light brown clear liquid.

After completion of the reaction, nitrogen gas was aerated at 100 to 150 ° C. at 10 L / hour for degassing.
The solvent orthodichlorobenzene was distilled off under reduced pressure, and a fraction having a boiling point of 138 to 140 ° C./0.7 KPa was further collected by distillation under reduced pressure.
As a result, 123 parts by mass (yield 90%) of 1,4-bis (isocyanatomethyl) cyclohexane was obtained as a colorless transparent liquid.

The purity of the obtained 1,4-bis (isocyanatomethyl) cyclohexane as measured by gas chromatography was 99.9%, the hue as measured by APHA was 5, and the trans / cis ratio as determined by ¹³ C-NMR was 93/7. It was.
Production Example 2 (Synthesis of polyoxyethylene side chain-containing diol)
In a four-necked flask equipped with a stirrer, a thermometer, a reflux tube, and a nitrogen introduction tube, 1000 parts by mass of methoxypolyethylene glycol having a number average molecular weight of 1000 (manufactured by Toho Chemical Co., Ltd.) and 1,6-hexamethylene diisocyanate ( 1682 parts by mass (trade name: Takenate-700, manufactured by Mitsui Chemicals Polyurethane Co., Ltd.) was charged and reacted at 90 ° C. for 9 hours in a nitrogen atmosphere. The obtained reaction liquid was subjected to thin-film distillation to remove unreacted 1,6-hexamethylene diisocyanate to obtain a polyoxyethylene group-containing monoisocyanate. Next, 82.5 parts by mass of diethanolamine was charged into a four-necked flask equipped with a stirrer, a thermometer, a reflux tube, and a nitrogen introduction tube, and the polyoxyethylene group-containing monoisocyanate 917. 5 parts by mass were gradually added dropwise so that the reaction temperature did not exceed 70 ° C. After completion of dropping, the mixture was stirred at 70 ° C. in a nitrogen atmosphere for about 1 hour to confirm that the isocyanate group had disappeared, and a polyoxyethylene side chain-containing diol was obtained.

The concentration of oxyethylene groups in the polyoxyethylene side chain-containing diol was 76% by mass as measured by ¹ H-NMR.
Synthesis Example 1 (Synthesis of hydrophilic group-containing prepolymer solution (A))
1,4-bis (isocyanatomethyl) cyclohexane (hereinafter abbreviated as 1,4-BIC) of Production Example 1 was added to a four-necked flask equipped with a stirrer, a thermometer, a reflux tube, and a nitrogen introduction tube. 380 parts by mass, heated to 110 ° C. in advance and dried under reduced pressure, and 3000 parts by mass of amorphous polycarbonate diol having a number average molecular weight of 2000 (trade name: T-5562, manufactured by Asahi Kasei Chemicals Corporation), acetonitrile (hereinafter referred to as AN) 1000 parts by weight, and 220 parts by weight of dimethylolpropionic acid (hereinafter abbreviated as DMPA) heated in the same manner as the amorphous polycarbonate diol and dried under reduced pressure were charged under a nitrogen atmosphere. The reaction was performed at 75 ° C. for 8 hours. As a result, an isocyanate group-terminated prepolymer (hereinafter abbreviated as prepolymer) solution having an isocyanate group content of 1.40% by mass was obtained.

Next, the reaction solution was cooled to 20 ° C., and 158 parts by mass of triethylamine (hereinafter abbreviated as TEA) was added. That is, TEA was added so that it might become an equivalent of 0.95 with respect to the hydrophilic group (carboxyl group) in an isocyanate group terminal prepolymer.
Thereafter, by stirring and mixing at the same temperature for 30 minutes, a hydrophilic group-containing isocyanate group-terminated prepolymer (hereinafter abbreviated as a hydrophilic group-containing prepolymer) solution (A) in which the carboxylic acid has been neutralized by TEA is obtained. Obtained. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (A) are shown in Table 1.

In Table 1, “equivalent ratio of isocyanate groups” represents the equivalent ratio of isocyanate groups of polyisocyanate to hydroxyl groups of active hydrogen compounds containing a high molecular weight polyol and a hydrophilic group.
Synthesis Example 2 (Synthesis of hydrophilic group-containing prepolymer solution (B))
The isocyanate group content was 2.65 masses in the same manner as in Synthesis Example 1 except that 950 mass parts of 1,4-BIC, 1045 mass parts of AN, 230 mass parts of DMPA, and 165 mass parts of TEA were used. % Hydrophilic group-containing prepolymer solution (B) was obtained. Table 1 shows the details of synthesis conditions and properties of the obtained hydrophilic group-containing prepolymer solution (B).

Synthesis Example 3 (Synthesis of hydrophilic group-containing prepolymer solution (C))
The isocyanate group content was 4.23 masses in the same manner as in Synthesis Example 1 except that 1,4-BIC was used in 1200 mass parts, AN in 1111 mass parts, DMPA in 244 mass parts, and TEA in 175 mass parts. % Hydrophilic group-containing prepolymer solution (C) was obtained. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (C) are shown in Table 1.

Synthesis Example 4 (Synthesis of hydrophilic group-containing prepolymer solution (D))
The isocyanate group content was 5.96 masses in the same manner as in Synthesis Example 1 except that 1500 parts by mass of 1,4-BIC, 1190 mass parts of AN, 260 mass parts of DMPA, and 186 mass parts of TEA were used. % Hydrophilic group-containing prepolymer solution (D) was obtained. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (D) are shown in Table 1.

Synthesis Example 5 (Synthesis of hydrophilic group-containing prepolymer solution (E))
1,3-bis (isocyanatomethyl) cyclohexane (trade name: Takenate T-600, manufactured by Mitsui Chemicals Polyurethane) (hereinafter abbreviated as 1,3-BIC) 950 parts by mass, AN 1045 parts by mass, DMPA In the same manner as in Synthesis Example 1, except that 230 parts by mass of TEA and 165 parts by mass of TEA were used, a hydrophilic group-containing prepolymer solution (E) having an isocyanate group content of 2.62% by mass was obtained. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (E) are shown in Table 1.

Synthesis Example 6 (Synthesis of hydrophilic group-containing prepolymer solution (F))
1, 4 428 parts by mass of -BIC and 1, 3 523 parts by mass of -BIC, 1045 parts by mass of AN, 230 parts by weight of DMPA, except for using 165 parts by weight of TEA is the same operation as in Synthesis Example 1 Thus, a hydrophilic group-containing prepolymer solution (F) having an isocyanate group content of 2.69% by mass was obtained. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (F) are shown in Table 1.

Synthesis Example 7 (Synthesis of hydrophilic group-containing prepolymer solution (G))
The same operation as in Synthesis Example 1 except that 1160 parts by mass of isophorone diisocyanate (IPDI, trade name: VESTANAT IPDI, manufactured by Degussa), 1105 parts by mass of AN, 260 parts by mass of DMPA, and 186 parts by mass of TEA were used. The hydrophilic group containing prepolymer solution (G) whose isocyanate group content is 2.68 mass% was obtained. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (G) are shown in Table 1.

Synthesis Example 8 (Synthesis of hydrophilic group-containing prepolymer solution (H))
1,370 parts by mass of 4,4′-methylenebis (cyclohexyl isocyanate) (trade name: VESTANAT H ₁₂ MDI, manufactured by Degussa) (hereinafter abbreviated as H ₁₂ MDI), 1158 parts by mass of AN, and 260 parts by mass of DMPA A hydrophilic group-containing prepolymer solution (H) having an isocyanate group content of 2.54% by mass was obtained in the same manner as in Synthesis Example 1, except that 186 parts by mass of TEA was used. The details and properties of the synthesis conditions of the obtained hydrophilic group-containing prepolymer solution (H) are shown in Table 1.

Synthesis Example 9 (Synthesis of hydrophilic group-containing prepolymer solution (I))
In a four-necked flask equipped with a stirrer, thermometer, reflux tube, and nitrogen introduction tube, 129 parts by mass of 4,4′-methylenebis (cyclohexyl isocyanate) (H ₁₂ MDI), amorphous polycarbonate diol (trade name) : T-5652) was charged in 3000 parts by mass, AN in 1054 parts by mass, DMPA in 232 parts by mass, reacted in a nitrogen atmosphere at 75 ° C. for 3 hours, and then 1,4-BIC was added in 856 parts by mass. The mixture was further reacted at the same temperature for 6 hours. As a result, a prepolymer solution having an isocyanate group content of 2.65% by mass was obtained.

  Subsequently, this reaction liquid was cooled to 20 ° C., and 166 parts by mass of TEA was added. That is, TEA was added so that it might become an equivalent of 0.95 with respect to the hydrophilic group (carboxyl group) in an isocyanate group prepolymer. Then, the hydrophilic group containing prepolymer solution (I) by which carboxylic acid was neutralized by TEA was obtained by stirring and mixing for 30 minutes at the same temperature. Table 1 shows the synthesis conditions and properties of the obtained hydrophilic group-containing prepolymer solution (I).

Synthesis Example 10 (Synthesis of prepolymer solution (J))
In a four-necked flask equipped with a stirrer, thermometer, reflux tube, and nitrogen introduction tube, 447 parts by mass of 1,4-BIC was heated to 110 ° C. in advance and dried under reduced pressure, and was amorphous with a number average molecular weight of 2000 Polycarbonate diol (trade name: T-5562, manufactured by Asahi Kasei Chemicals Co., Ltd.) 3000 parts by mass, AN 1452 parts by mass, acetone 1515 parts by mass, and heated in the same manner as amorphous polycarbonate diol and dried under reduced pressure 389 parts by mass of oxyethylene side chain-containing diol was charged and reacted at 75 ° C. for 7 hours in a nitrogen atmosphere. As a result, a prepolymer solution (J) having an isocyanate group content of 0.57% by mass was obtained. The details and properties of the synthesis conditions of the obtained prepolymer solution (J) are shown in Table 1.

Synthesis Example 11 (Synthesis of prepolymer solution (K))
In the same manner as in Synthesis Example 10, except that 496 parts by mass of 1,4-BIC, 1473 parts by mass of AN, 1841 parts by mass of acetone, and 394 parts by mass of a polyoxyethylene side chain-containing diol were used. A prepolymer solution (K) having a content of 0.81% by mass was obtained. The details and properties of the synthesis conditions of the obtained prepolymer solution (K) are shown in Table 1.

Synthesis Example 12 (Synthesis of prepolymer solution (L))
An isocyanate group was prepared in the same manner as in Synthesis Example 10, except that 799 parts by mass of 1,4-BIC, 1600 parts by mass of AN, 2001 parts by mass of acetone, and 428 parts by mass of a diol containing a polyoxyethylene side chain were used. A prepolymer solution (L) having a content of 2.35% by mass was obtained. The details and properties of the synthesis conditions of the resulting prepolymer solution (L) are shown in Table 1.

Synthesis Example 13 (Synthesis of prepolymer solution (M))
The isocyanate group content was the same as in Synthesis Example 10 except that 676 parts by mass of H ₁₂ MDI, 1548 parts by mass of AN, 1936 parts by mass of acetone, and 414 parts by mass of diol containing a polyoxyethylene side chain were used. A 0.8 mass% prepolymer solution (M) was obtained. The details and properties of the synthesis conditions of the resulting prepolymer solution (M) are shown in Table 1.

Reference Example 1 (Synthesis of aqueous polyurethane resin (A))
1000 parts by mass of ion-exchanged water adjusted to 10 ° C. in advance is placed in a 3 L-volume stainless steel container, and a homodisper (trade name: TK homodisper, manufactured by Primix Co., Ltd.) is used. 500 parts by mass of the hydrophilic group-containing prepolymer solution (A) adjusted to ° C. was gradually added and dispersed.

Next, 3.85 parts by mass of hydrazine and 19.2 parts by mass of a chain extender solution prepared in a 20% by mass aqueous solution were gradually added while paying attention to heat generation. The equivalent ratio of amino groups in the chain extender to isocyanate groups in the prepolymer (hereinafter abbreviated as equivalent ratio of chain extender) was 0.95.
In addition, hydrazine uses hydrazine monohydrate (manufactured by Wako Pure Chemical Industries, Ltd.), and the mass part of hydrazine corresponds to hydrazine monohydrate (chains in the following examples and comparative examples). The same applies to the description regarding the equivalent ratio of the extender and the amount of hydrazine used.)
And after adding a chain extender liquid, it stirred at 10-25 degreeC for 2 hours, and was made to carry out chain extension reaction. Further, AN was distilled off under reduced pressure to obtain an aqueous dispersion of an aqueous polyurethane resin (A) having a solid content of 35% by mass. Table 2 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (A).

Example 2 (Synthesis of aqueous polyurethane resin (B))
Using the hydrophilic group-containing prepolymer solution (B), as a chain extender, 5.82 parts by mass of hydrazine and N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (trade name: KBM602 Shin-Etsu Chemical Co., Ltd.) The same conditions as in Reference Example 1 except that 59.1 parts by mass of the chain extender solution prepared in the form of a 20% by mass aqueous solution and 6.00 parts by mass of Si atom content (13.6% by mass) were used. By operation, an aqueous dispersion of the aqueous polyurethane resin (B) was obtained. Table 2 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (B).

Reference Example 3 (Synthesis of aqueous polyurethane resin (C))
Reference Example 1 was used except that the hydrophilic group-containing prepolymer solution (B) was used and, as the chain extender, 7.27 parts by mass of hydrazine and 36.4 parts by mass of a chain extender solution prepared in a 20% by mass aqueous solution were used. Under the same conditions and operation, an aqueous dispersion of the aqueous polyurethane resin (C) was obtained. Table 2 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (C).

Example 4 (Synthesis of aqueous polyurethane resin (D))
A chain prepared by using 30.0 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) as a chain extender in a 20% by mass aqueous solution using the hydrophilic group-containing prepolymer solution (B). An aqueous dispersion of an aqueous polyurethane resin (D) was obtained under the same conditions and operation as in Reference Example 1 except that 149.9 parts by mass of the extender solution was used. Table 2 shows the details of synthesis conditions and properties of the obtained water-based polyurethane resin (D).

Reference Example 5 (Synthesis of aqueous polyurethane resin (E))
Reference Example 1 except that the hydrophilic group-containing prepolymer solution (C) was used, and 11.6 parts by mass of hydrazine as a chain extender was used in 58.0 parts by mass of a chain extender solution prepared in a 20% by mass aqueous solution. An aqueous dispersion of an aqueous polyurethane resin (E) was obtained under the same conditions and operations. Table 2 shows the details and properties of the synthesis conditions of the obtained water-based polyurethane resin (E).

Example 6 (Synthesis of aqueous polyurethane resin (F))
Using the hydrophilic group-containing prepolymer solution (D), as a chain extender, 4.91 parts by mass of hydrazine and 47.2 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) An aqueous dispersion of an aqueous polyurethane resin (F) was obtained under the same conditions and operation as in Reference Example 1 except that 260.5 parts by mass of the chain extender solution prepared in a 20% by mass aqueous solution was used. Table 2 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (F).

Reference Example 7 (Synthesis of aqueous polyurethane resin (G))
Reference Example 1 except that the hydrophilic group-containing prepolymer solution (D) was used and 11.8 parts by mass of a chain extender solution prepared in a 20% by mass aqueous solution was used as the chain extender. Under the same conditions and operation, an aqueous dispersion of the aqueous polyurethane resin (G) was obtained. Table 2 shows the details of synthesis conditions and properties of the obtained aqueous polyurethane resin (G).

Reference Example 8 (Synthesis of aqueous polyurethane resin (H))
Reference Example 1 except that the hydrophilic group-containing prepolymer solution (I) was used and, as the chain extender, 7.27 parts by mass of hydrazine and 36.4 parts by mass of a chain extender solution prepared in a 20% by mass aqueous solution were used. Under the same conditions and operation, an aqueous dispersion of an aqueous polyurethane resin (H) was obtained. The details and properties of the synthesis conditions of the resulting aqueous polyurethane resin (H) are shown in Table 2.

Example 9 (Synthesis of aqueous polyurethane resin (I))
500 g of the prepolymer solution (J) synthesized in Synthesis Example 10 was charged into a four-necked flask equipped with a stirrer, a thermometer, a reflux tube, and a nitrogen introduction tube, and heated to 30 ° C. Subsequently, 850 g of ion-exchanged water previously adjusted to 20 ° C. was gradually added to make it aqueous, and 0.85 parts by mass of hexamethylenediamine (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as HDA), N-β Chain extension was performed by adding 29.6 parts by mass of a chain extender solution prepared in 5.06 parts by mass of (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) to a 20% by mass aqueous solution.

And after adding a chain extender liquid, it stirred at 10-25 degreeC for 2 hours, and was made to carry out chain extension reaction. Furthermore, AN and acetone were distilled off under reduced pressure to obtain an aqueous dispersion of an aqueous polyurethane resin (I) having a solid content of 35% by mass. The details and properties of the synthesis conditions of the resulting aqueous polyurethane resin (I) are shown in Table 3.
Example 10 (Synthesis of aqueous polyurethane resin (J))
Using the prepolymer solution (K), as a chain extender, 2.4 parts by mass of HDA and 5.09 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) are 20% by mass. An aqueous dispersion of an aqueous polyurethane resin (J) was obtained under the same conditions and operation as in Example 9, except that 37.4 parts by mass of the chain extender solution prepared in the aqueous solution was used. The details and properties of the synthesis conditions of the obtained water-based polyurethane resin (J) are shown in Table 3.

Example 11 (Synthesis of aqueous polyurethane resin (K))
Using the prepolymer solution (L), as a chain extender, 12.3 parts by mass of HDA and 5.28 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) are 20% by mass. An aqueous dispersion of an aqueous polyurethane resin (K) was obtained under the same conditions and operation as in Example 9, except that 87.9 parts by mass of the chain extender solution prepared in the aqueous solution was used. Table 3 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (K).

Comparative Example 1 (Synthesis of aqueous polyurethane resin (L))
Using the hydrophilic group-containing prepolymer solution (E), 5.75 parts by mass of hydrazine and 5.93 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane) (KBM602) as a chain extender An aqueous dispersion of an aqueous polyurethane resin (L) was obtained under the same conditions and operation as in Reference Example 1 except that 58.4 parts by mass of the chain extender solution prepared in a 20% by mass aqueous solution was used. Table 2 shows the details of synthesis conditions and properties of the obtained water-based polyurethane resin (L).

Comparative Example 2 (Synthesis of aqueous polyurethane resin (M))
Reference Example 1 was used except that the hydrophilic group-containing prepolymer solution (F) was used and, as the chain extender, 7.38 parts by mass of hydrazine was used in 36.9 parts by mass of a chain extender solution prepared in a 20% by mass aqueous solution. An aqueous dispersion of an aqueous polyurethane resin (M) was obtained under the same conditions and operations. Table 2 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (M).

Comparative Example 3 (Synthesis of aqueous polyurethane resin (N))
A chain prepared by using 30.2 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) as a chain extender in a 20% by mass aqueous solution using a hydrophilic group-containing prepolymer solution (G) An aqueous dispersion of an aqueous polyurethane resin (N) was obtained under the same conditions and operation as in Reference Example 1 except that 151.1 parts by mass of the extender solution was used. Table 2 shows details and properties of the synthesis conditions of the obtained water-based polyurethane resin (N).

Comparative Example 4 (Synthesis of aqueous polyurethane resin (O))
Chain extension which prepared 28.7 mass parts of N-beta (aminoethyl) -gamma-aminopropylmethyldimethoxysilane (KBM602) as a chain extender in 20 mass% aqueous solution using hydrophilic group content prepolymer (H). An aqueous dispersion of an aqueous polyurethane resin (O) was obtained under the same conditions as in Reference Example 1 except that 143.5 parts by mass of the agent solution was used. Table 2 shows the details of synthesis conditions and properties of the obtained aqueous polyurethane resin (O).

Comparative Example 5 (Synthesis of aqueous polyurethane resin (P))
Using the prepolymer solution (M), 2.35 parts by mass of HDA and 5.10 parts by mass of N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane (KBM602) as a chain extender are 20% by mass. An aqueous dispersion of an aqueous polyurethane resin (P) was obtained under the same conditions and operation as in Example 9, except that 37.3 parts by mass of the chain extender solution prepared in the aqueous solution was used. Table 3 shows details and properties of the synthesis conditions of the obtained aqueous polyurethane resin (P).

Physical property evaluation Si atom concentration, mechanical stability, oleic acid resistance, elongation at break, softening temperature, wind of aqueous polyurethane resin (hereinafter abbreviated as each aqueous polyurethane resin) obtained in each example and each comparative example Conformity and tactile sensation were measured by the following methods. The results are shown in Table 2.
<Preparation of test sample>
Examples 2, 4 and 6, Reference Examples 1, 3, 5, 7 and 8 and Comparative Examples 1-4
Each aqueous polyurethane resin was applied onto an OHP film degreased with acetone using an applicator and dried at 110 ° C. for 1 hour to obtain a film having a thickness of about 60 μm. The film was then cured for 1 week in a laboratory at 23 ° C. and 55% relative humidity. This produced a test sample.

Examples 9-11, Comparative Example 5
Each aqueous polyurethane resin was placed in a plastic tray and coagulated by applying saturated steam at 90 ° C. or higher for about 1 minute. The film was allowed to stand overnight at 23 ° C. and a relative humidity of 55%, and then dried at 110 ° C. for 2 hours to obtain a film having a thickness of about 250 μm. The film was then cured for 1 week in a laboratory at 23 ° C. and 55% relative humidity. This produced a test sample.
<Si atom concentration (unit: mass%)>
By using a wet ashing method using nitric acid and sulfuric acid (for example, “Analytical Chemistry Handbook”, Japanese Society for Analytical Chemistry, publisher, Maruzen Co., Ltd., published on November 30, 1991, page 1292) The organic component of the polyurethane test sample was completely decomposed and then heated to obtain a dried product.

Next, powdered sodium carbonate was added to the dried product, and further heated to dissolve the dried product in a molten salt of sodium carbonate.
The sample was allowed to cool, solidified, and slowly added with dilute hydrochloric acid until it became weakly acidic, so that an analytical sample was prepared (for example, “Analytical Chemistry Handbook”, edited by the Japan Analytical Chemical Society, publisher) Maruzen Co., Ltd., issued on November 30, 1991, pages 265-266).

Using this analysis sample, the concentration of Si atoms in each aqueous polyurethane resin was measured with an ICP emission analyzer (ICP-AES, manufactured by Seiko Instruments Inc., model: VISTA-PRO).
In addition, the description of “nd” in Table 2 means that there is no measurement value because no Si atom is contained.
<Mechanical stability: Maron test (unit: μg / g)>
A test solution of an aqueous dispersion of each water-based polyurethane resin having a solid content of 5% by weight diluted with ion-exchanged water is passed through a # 300 mesh wire mesh beforehand, and then 100 g of the resin remaining on the wire mesh is used exclusively for mechanical stability test. Weighed into a cup.

Next, shear was applied for 20 minutes under the conditions of a load of 147 N (15 kgf) and a rotational speed of 1000 rpm using a Maron mechanical stability tester (manufactured by Rigaku Corporation) (Maron test).
Subsequently, the resin after the test was filtered through a # 300 mesh wire net, and the wire net was dried at 110 ° C. for 1 hour.

The mass of the wire mesh before and after the Maron test was measured, and the mass of the resin remaining on the wire mesh was measured. Based on the measured mass, it was converted into the amount of resin remaining on the wire mesh per solid content of each aqueous polyurethane resin.
<Oleic acid resistance (unit:%)>
A test sample of each aqueous polyurethane resin was cut into a size of 1 × 10 cm, and the mass of the test sample was measured. Subsequently, it was immersed in oleic acid at 23 ° C. for 7 days. After immersion, before the mass measurement of the test sample, the oleic acid adhering to the surface of the test sample was quickly wiped off. And the mass of the test sample after immersion was measured. From the mass of the test sample before and after immersion in oleic acid, the oleic acid resistance (%) was calculated by the following formula.
Oleic acid resistance (%) = (mass of test sample after immersion (g) −mass of test sample before immersion (g)) / mass of test sample before immersion × 100
<Softening temperature (unit: ° C)>
A test sample of each aqueous polyurethane resin was punched into a size of 5 mm in width and 50 mm in length with a dumbbell. Next, with respect to this test sample, using a dynamic viscoelasticity measuring apparatus (Model: DVA-200, manufactured by IT Measurement Control Co., Ltd.), tensile mode, length between marked lines 25 mm, heating rate 5 ° C./min, measurement The dynamic viscoelasticity of the test sample was measured under the condition of a frequency of 10 Hz. In the region where the storage elastic modulus of the rubber or leather-like flat region is inflected, the intersection of each tangent of the storage elastic modulus was obtained, and this temperature was defined as the softening temperature.
<Elongation at break (EL) (Unit:%)>
A test sample of each aqueous polyurethane resin was punched with a dumbbell into a size of 1 cm in width and 10 cm in length. Next, the test sample was subjected to a tensile test using a tensile / compression tester (Model 205N, manufactured by Intesco) under the conditions of 23 ° C., a tensile speed of 300 mm / min, and a distance between chucks of 50 mm. Thereby, the elongation at break (EL) of each aqueous polyurethane resin was measured.
<Feeling>
The tack (tackiness) and tactile sensation of each aqueous polyurethane resin test sample were evaluated by palpation according to the following evaluation criteria. Based on these results, the texture was further evaluated according to the following evaluation criteria.
(Feel)
○: Both tack and tactile sensation are ○.
(Triangle | delta): Tack is (circle) and tactile sense is (triangle | delta).
X: Either tack or tactile sensation is x.
(Tack evaluation criteria)
○: Tack is not recognized.
Δ: Slight tack is observed.
X: Tack is recognized.
(Evaluation criteria for tactile sensation)
○: A soft tactile sensation.
Δ: Slight streaks remain when bent.
X: Streaks remain clearly when bent.

  Although the above description has been provided as an exemplary embodiment of the present invention, this is merely an example and should not be construed as limiting. Modifications of the present invention apparent to those skilled in the art are intended to be included within the scope of the following claims.

The aqueous polyurethane resin of the present invention is suitably used for providing a coating film or artificial or synthetic leather.

Claims (6)

A polyisocyanate containing an isocyanate group of 1,4-bis (isocyanatomethyl) cyclohexane in a proportion of 50 mol% or more with respect to the total number of moles of isocyanate groups , a high molecular weight polyol having a number average molecular weight of 400 to 5,000 , And an isocyanate group-terminated prepolymer obtained by reacting at least an active hydrogen compound containing at least one hydrophilic group selected from the group consisting of an anionic group, a cationic group and a nonionic group ;
An aqueous polyurethane resin obtained by a reaction with a chain extender containing an active hydrogen compound containing an alkoxysilyl group .   The water-based polyurethane resin according to claim 1, which contains 0.05 to 1.5 mass% of Si atoms. The chain extender, characterized in that a compound represented by the following general formula (1), according to claim 1, wherein the aqueous polyurethane resin.
General formula (1):

(In the formula, R1 and R2 are the same or different and each represent an alkyl group having 1 to 4 carbon atoms. R3 and R4 are the same or different and each represent an alkylene group having 1 to 4 carbon atoms. Represents an integer of ~ 3.)   The aqueous polyurethane resin according to claim 1, wherein 1,4-bis (isocyanatomethyl) cyclohexane contains 50% by mass or more of trans-1,4-bis (isocyanatomethyl) cyclohexane.   A coating film obtained from the aqueous polyurethane resin according to claim 1. An artificial or synthetic leather, wherein the aqueous polyurethane resin according to claim 1 is used.