JP6225979B2 - Aqueous polyurethane resin dispersion composition and method for producing the same - Google Patents

Description

  The present invention relates to an aqueous polyurethane resin dispersion composition in which a plurality of types of polyurethane resins are dispersed in an aqueous medium, a method for producing the same, and a coating agent composition, a coating composition and a synthesis containing the aqueous polyurethane resin dispersion composition. The present invention relates to a leather composition.

  Polycarbonate polyol is a useful compound that becomes a raw material for producing a polyurethane resin used for a rigid foam, a flexible foam, a paint, an adhesive, a synthetic leather, an ink binder and the like by reaction with an isocyanate compound. It is known that a coating film obtained using an aqueous polyurethane resin dispersion made of polycarbonate polyol as a raw material is excellent in light resistance, heat resistance, hydrolysis resistance, and oil resistance (see Patent Documents 1 and 2).

JP-A-10-120757 JP-A-6-248046

  However, the coating film obtained using the aqueous polyurethane resin dispersion has a hardness of the coating film, for example, depending on the type of base material to be coated, such as an outer plate of an aircraft or an automobile, an outer wall surface of a house, and a flooring material. In some cases, this was not sufficient. Also, depending on the type of substrate to be coated, the coating film obtained using the aqueous polyurethane resin dispersion has cracks and the like, and the hardness of the coating film decreases when dried at a low temperature (20 ° C.). There was a case. In addition, for example, when an aqueous polyurethane resin dispersion is applied to a metal substrate, the obtained coating film cannot achieve both the effect of preventing metal corrosion and the flexibility to avoid the occurrence of cracks in bending. It was.

  The present invention provides a base material that deforms when exposed to high temperatures such as thermoplastic resin, rubber, and elastomer, a base material that deforms or discolors when exposed to high temperatures such as wood, a flexible base material, and a metal base material. Even when applied, an aqueous polyurethane resin dispersion composition is obtained that is resistant to cracking, exhibits high hardness, has excellent solvent resistance, and provides a coating film that can prevent metal corrosion in a salt spray test. Is an issue.

  The present inventors have studied to overcome the above-mentioned problems of the prior art. As a result, the polyurethane resin obtained by using an aliphatic polycarbonate polyol and the polyurethane resin obtained by using a polycarbonate polyol having an alicyclic structure are obtained. It was found that an aqueous polyurethane resin dispersion composition satisfying the above required performance can be obtained by dispersing in a water-based medium.

Specifically, the present invention is as follows.
[1] An aqueous polyurethane resin dispersion composition in which at least a polyurethane resin (A) and a polyurethane resin (B) are dispersed in an aqueous medium,
The polyurethane resin (A) is obtained by reacting at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ). Polyurethane resin,
The polyurethane resin (B) includes at least a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), a polyisocyanate compound (d _B ), and a chain extender (e _B Is a polyurethane resin obtained by reacting
An aqueous polyurethane resin dispersion composition.
[2] Polyurethane resin (A) is a polyol other than aliphatic polycarbonate polyol (a _A ), acidic group-containing polyol compound (b _A ), aliphatic polycarbonate polyol (a _A ), and acidic group-containing polyol compound (b _A ) The aqueous polyurethane resin dispersion composition according to [1], which is a polyurethane resin obtained by reacting (c _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ).
[3] The polyurethane resin (A) reacts the aliphatic polycarbonate polyol (a _A ) and the acidic group-containing polyol compound (b _A ) with the polyisocyanate compound (d _A ) to convert the polyurethane prepolymer (A _p ). Next, the aqueous polyurethane resin dispersion composition according to [1], which is a polyurethane resin obtained by reacting a polyurethane prepolymer (A _p ) with a chain extender (e _A ).
[4] Polyurethane resin (A) is an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), and a polyol other than the aliphatic polycarbonate polyol (a _A ) and acidic group-containing polyol compound (b _A ) (C _A ) and a polyisocyanate compound (d _A ) are reacted to obtain a polyurethane prepolymer (A _p ), and then the polyurethane prepolymer (A _p ) and a chain extender (e _A ) are reacted. The aqueous polyurethane resin dispersion composition according to [2], which is a polyurethane resin to be obtained.
[5] A linear or branched polyurethane resin (B) having a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5,000. The aqueous polyurethane according to any one of [1] to [4], which is a polyurethane resin obtained by reacting a chain polyol (c _B ), a polyisocyanate compound (d _B ), and a chain extender (e _B ). Resin dispersion composition.
[6] Polyurethane resin (B) reacts with polycarbonate polyol (a _B ) and acidic group-containing polyol compound (b _B ) having an alicyclic structure in the main chain, and a polyisocyanate compound (d _B ) to form polyurethane. obtaining prepolymer (B _p), then a polyurethane resin obtained by reacting a polyurethane prepolymer (B _p) and chain extender (e _B), according to any one of [1] to [4] An aqueous polyurethane resin dispersion composition.
[7] Linear or branched polyurethane resin (B) having a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5,000. A chain polyol (c _B ) and a polyisocyanate compound (d _B ) are reacted to obtain a polyurethane prepolymer (B _p ), and then the polyurethane prepolymer (B _p ) and a chain extender (e _B ) The aqueous polyurethane resin dispersion composition according to any one of [1] to [5], which is a polyurethane resin obtained by reacting.
[8] The linear or branched polyol (c _B ) having a number average molecular weight of 500 to 5,000 is a polyether polyol having no alicyclic structure in the main chain. The aqueous polyurethane resin dispersion composition according to any one of the above.
[9] The aqueous polyurethane resin according to any one of [1] to [8], wherein the mixing ratio of the polyurethane resin (A) and the polyurethane resin (B) is 3/97 to 75/25 in terms of solid content ratio. Dispersion composition.
[10] The aqueous polyurethane resin dispersion composition according to [9], wherein the mixing ratio of the polyurethane resin (A) and the polyurethane resin (B) is 5/95 to 80/20 in terms of solid content.
[11] The aqueous polyurethane resin dispersion composition according to [10], wherein the mixing ratio of the polyurethane resin (A) and the polyurethane resin (B) is 30/70 to 55/45 in terms of solid content.
[12] A coating agent composition comprising the aqueous polyurethane resin dispersion composition according to any one of [1] to [11].
[13] A coating composition containing the aqueous polyurethane resin dispersion composition according to any one of [1] to [11].
[14] The coating composition according to [13], which is for metal coating.
[15] A composition for synthetic leather containing the aqueous polyurethane resin dispersion composition according to any one of [1] to [11].
[16] A method for producing the aqueous polyurethane resin dispersion composition according to any one of [1] to [11], wherein the polyurethane resin (A) is dispersed in an aqueous medium; The manufacturing method including the process of mixing with the aqueous | water-based polyurethane resin dispersion in which a polyurethane resin (B) is disperse | distributing in the aqueous medium.

  According to the present invention, a base material that deforms when exposed to a high temperature such as a thermoplastic resin, rubber, or elastomer, a base material that deforms or discolors when exposed to a high temperature such as a wood, or a plastic base material is coated. However, it is possible to obtain an aqueous polyurethane resin dispersion composition that is less prone to cracking and provides a coating film that can exhibit high altitude even when dried at a low temperature such as 20 ° C. In addition, according to the present invention, even when applied to a metal substrate, it is water-based to produce a coating film that is less susceptible to cracking in bending, has excellent solvent resistance, and can prevent metal corrosion in a salt spray test. A polyurethane resin dispersion composition can be provided. The aqueous polyurethane resin dispersion composition of the present invention is useful as a raw material for a coating composition, a coating agent, a primer, etc., and in particular, a coating composition, a coating agent composition, a synthetic leather composition applied to a metal substrate. Highly useful as a product.

It is a schematic diagram showing the state of the test piece in a salt spray test. It is a photograph which shows the state of the test piece 120 hours after in a salt spray test.

  The present invention relates to an aqueous polyurethane resin dispersion composition in which at least a polyurethane resin (A) and a polyurethane resin (B) are dispersed in an aqueous medium.

The present invention is an aqueous polyurethane resin dispersion composition in which at least a polyurethane resin (A) and a polyurethane resin (B) are dispersed in an aqueous medium,
The polyurethane resin (A) is obtained by reacting at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ). Polyurethane resin,
The polyurethane resin (B) includes at least a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), a polyisocyanate compound (d _B ), and a chain extender (e _B Is a polyurethane resin obtained by reacting
The present invention relates to an aqueous polyurethane resin dispersion composition.

Furthermore, the present invention is an aqueous polyurethane resin dispersion composition in which at least a polyurethane resin (A) and a polyurethane resin (B) are dispersed in an aqueous medium,
The polyurethane resin (A) is obtained by reacting at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ). Polyurethane resin,
The polyurethane resin (B) is at least a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), a linear or branched chain having a number average molecular weight of 500 to 5,000. Jo polyol (c _B), the polyisocyanate compound (d _B), and a polyurethane resin obtained by reacting a chain extender (e _B), an aqueous polyurethane resin dispersion composition.

[Polyurethane resin (A)]
The polyurethane resin (A) in the present invention reacts at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ). Polyurethane resin obtained in this way. The polyurethane resin (A) of the present invention may be obtained by reacting a polyol (c _A ) other than the aliphatic polycarbonate polyol (a _A ) and the acidic group-containing polyol compound (b _A ) in addition to the above components.

(Aliphatic polycarbonate polyol (a _A ))
The aliphatic polycarbonate polyol (a _A ) in the present invention refers to a polycarbonate polyol in which the portion constituting the main chain other than the carbonate structure and the hydroxyl group is a linear or branched hydrocarbon group. Accordingly, the aliphatic polycarbonate polyol (a _A ) does not have both an alicyclic structure and an aromatic structure in the main chain. In the present specification, “aliphatic” refers to a linear or branched hydrocarbon.

The aliphatic polycarbonate polyol (a _A ) may be a linear aliphatic polycarbonate polyol or a branched aliphatic polycarbonate polyol. Further, in the main chain of the aliphatic polycarbonate polyol (a _A ), a linear hydrocarbon group (for example, a linear alkylene group) and a branched hydrocarbon group (for example, a branched alkylene group) are present. May coexist.

  The number of hydroxyl groups in the aliphatic polycarbonate polyol is not particularly limited, but an aliphatic polycarbonate diol having two hydroxyl groups is preferable from the viewpoint of improving the solvent resistance of the coating film.

The number average molecular weight of the aliphatic polycarbonate polyol (a _A ) is not particularly limited, and is preferably 400 to 6,000. If it is this range, sufficient crack suppression effect and hardness can be easily provided to the coating film obtained using an aqueous polyurethane resin dispersion composition. The number average molecular weight is more preferably 600 to 4,000, and particularly preferably 900 to 3,500.

In this specification, the number average molecular weight is the number average molecular weight calculated based on the hydroxyl value (mgKOH / g) measured according to JIS K 1577. For example, when N hydroxyl groups are present in the molecule, it can be calculated from the hydroxyl value by the following formula.
Number average molecular weight = (56,100 × N) / (hydroxyl value of polycarbonate polyol)

The method for synthesizing the aliphatic polycarbonate polyol (a _A ) is not particularly limited. For example, the transesterification reaction between at least one aliphatic polyol and a carbonate ester, or the reaction between at least one aliphatic polyol and phosgene. Can be obtained. When a plurality of types of aliphatic polyols are used, a method of synthesizing a plurality of types of aliphatic polyols by reacting them with a carbonate ester or phosgene, a polycarbonate obtained by reacting a specific type of aliphatic polyol with a carbonate ester or phosgene. Examples thereof include a method in which a polyol is obtained and synthesized by reacting it with another aliphatic polyol and a carbonate ester or phosgene. The aliphatic polycarbonate polyol (a _A ) obtained by the transesterification reaction is preferable because the chlorine content is low and side reactions such as coloring hardly occur.

  In order to synthesize a polycarbonate polyol from an aliphatic polyol and a carbonate ester, for example, an aliphatic polyol having an excess number of moles relative to the number of moles of carbonate ester is charged in a reactor, and the temperature is 160 to 200 ° C. and the pressure is about 50 mmHg And a method of reacting at 200 to 220 ° C. for several hours at a pressure of several mmHg or less. In the reaction, it is preferable to carry out the reaction while extracting by-produced alcohol out of the system. At that time, if the carbonate ester escapes from the system by azeotroping with the by-produced alcohol, it is necessary to charge an excessive amount of the carbonate ester. In the above reaction, a catalyst such as titanium tetrabutoxide may be used.

  The aliphatic polyol is not particularly limited, and for example, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8 Linear aliphatic diols such as octanediol and 1,9-nonanediol; 2-methyl-1,3-propanediol, neopentyl glycol, 2-methyl-1,4-butanediol, 2-methyl-1 , 5-pentanediol, 3-methyl-1,5-pentanediol, 1,4-pentanediol, 1,5-hexanediol, 2-methyl-1,6-hexanediol, 3-methyl-1,6- Multivalents such as branched chain aliphatic diols such as hexanediol and 1,6-heptanediol, trimethylolpropane, pentaerythritol, sorbitol Alcohol, and the like. These aliphatic polyols may be used individually by 1 type, and may use multiple types together.

  The carbonate is not particularly limited, and examples thereof include aliphatic carbonates such as dimethyl carbonate, diethyl carbonate, and methyl ethyl carbonate, aromatic carbonates such as diphenyl carbonate, and cyclic carbonates such as ethylene carbonate. Of these, aliphatic carbonates are preferable and dimethyl carbonate is particularly preferable because of easy synthesis.

As the aliphatic polycarbonate polyol (a _A ), one type may be used alone, or a plurality of types may be used in combination.

(Acid group-containing polyol compound (b _A ))
The acidic group-containing polyol compound (b _A ) in the present invention refers to a compound having two or more hydroxyl groups and one or more acidic groups in the molecule. Examples of the acidic group include a carboxy group, a sulfonyl group, a phosphoric acid group, and a phenolic hydroxyl group, and a carboxy group is preferable. An acidic group-containing diol compound having two hydroxyl groups is preferred.

Among them, the acidic group-containing polyol compound (b _A ) is preferably a compound having two hydroxyl groups and one or more carboxy groups in the molecule, more preferably two or more hydroxyl groups and one carboxy group in the molecule. It is a compound which has this. A compound having at least two hydroxyl groups and a carboxy group in the molecule and an acidic group-containing polyol compound having at least two hydroxyl groups and at least one sulfonyl group, phosphoric acid group or phenolic hydroxyl group in the molecule are used in combination. You can also.

The acidic group-containing polyol compound (b _A ) is not particularly limited. For example, dimethylol alkanoic acid such as 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid; N, N-bishydroxyethylglycine N, N-bis (2-hydroxyethyl) alanine, 3,4-dihydroxybutanesulfonic acid, 3,6-dihydroxy-2-toluenesulfonic acid, N, N-bis (2-hydroxyethyl) -2-amino Examples include ethanesulfonic acid. Among these, dimethylol alkanoic acid is preferable from the viewpoint of easy availability, and 2,2-dimethylolpropionic acid is more preferable.

The acidic group-containing polyol compound (b _A ) may be used alone or in combination of two or more.

(Polyol (c _A ))
In the preparation of the polyurethane resin (A), using the aliphatic polycarbonate polyol _{(a A)} (hereinafter also referred to as "polyol _{(c A)")} and an acid group-containing polyol compound _{(b A)} other than the polyol _(c A) Also good.

The polyol (c _A ) is not particularly limited, and examples thereof include a low molecular weight polyol or a high molecular weight polyol, and preferably a low molecular weight polyol. In the present specification, the low molecular weight polyol means a polyol having a number average molecular weight of less than 500, and the high molecular weight polyol means a polyol having a number average molecular weight of 500 or more.

  The low molecular weight polyol is not particularly limited, and examples thereof include an aliphatic polyol having 2 to 9 carbon atoms or a polyol having an alicyclic structure having 3 to 12 carbon atoms. Specifically, ethylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3 -Propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, 2-methyl-1,8 -C2-C9 aliphatic diols such as octanediol, diethylene glycol, triethylene glycol, tetraethylene glycol; 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1 , 4-Bis (hydroxyethyl) cyclohexane, 2,7-norbornanediol, tetrahydride Furan dimethanol, 2,5-bis diols of the diol having an alicyclic structure having 4 to 12 carbon atoms such as (hydroxymethyl) -1,4-dioxane. In addition, polyols such as trimethylolpropane, pentaerythritol, sorbitol and the like may be used.

  The high molecular weight polyol is not particularly limited, but the number average molecular weight is 500 to 5,000, and the main chain of the high molecular weight polyol is preferably linear or branched.

Specifically, polycarbonate polyol (excluding aliphatic polycarbonate polyol (a _A )), polyester polyol, polyether polyol, and acrylic polyol can be preferably used. Examples of the polycarbonate polyol include aromatic polycarbonate polyols such as bisphenol A / polycarbonate.

  Polyester polyol is not particularly limited, for example, polyethylene adipate diol, polybutylene adipate diol, polyethylene butylene adipate diol, polyhexamethylene isophthalate adipate diol, polyethylene succinate diol, polybutylene succinate diol, polyethylene sebacate diol, Examples include polybutylene sebacate diol, poly-ε-caprolactone diol, poly (3-methyl-1,5-pentylene adipate) diol, polycondensate of 1,6-hexanediol and dimer acid, and the like.

  The polyether polyol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol (PTMG), ethylene oxide and propylene oxide, and a random copolymer or block copolymer of ethylene oxide and butylene oxide. . Furthermore, a polyether polyester polyol having an ether bond and an ester bond can also be used.

As the polyol (c _A ), one type may be used alone, or a plurality of types may be used in combination.

In the present invention, the total number of hydroxyl equivalents of the aliphatic polycarbonate polyol (a _A ), acidic group-containing polyol compound (b _A ) and optionally present polyol (c _A ) is determined by the ease of production and the hardness of the coating film. From the viewpoint, it is preferably 300 to 1,000, more preferably 400 to 800, and particularly preferably 500 to 700.

In this specification, the number of hydroxyl equivalents can be calculated by the following formula.
Number of hydroxyl equivalents of each polyol = molecular weight of each polyol / number of OH groups in each polyol Total number of hydroxyl equivalents = M / total number of moles of polyol M = total number of hydroxyl equivalents of each polyol × total number of moles of each polyol Polyurethane For resin (A), M is [[number of hydroxyl equivalents of aliphatic polycarbonate polyol (a _A ) × number of moles of polycarbonate polyol (a _A )] + [number of hydroxyl equivalents of acidic group-containing polyol compound (b _A ) × acidic group-containing polyol compound is _{(b a)} mol number of] + [(mol number of hydroxyl equivalent number × polyol _{(c a)} (polyol _{(c a))].}

(Polyisocyanate compound (d _A ))
The polyisocyanate compound (d _A ) in the present invention is not particularly limited as long as it has two or more isocyanato groups in the molecule. For example, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2 , 4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, 4,4′-diphenylenemethane diisocyanate (MDI), 2,4-diphenylmethane diisocyanate, 4,4′-diisocyanatobiphenyl, 3, 3′-dimethyl-4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4,4′-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, 4,4 ′, 4 ″ -tri Phenylmethane triisocyanate, m-isocyanatophenylsulfonyl isocyanate, p- Aromatic polyisocyanate compounds such as soocyanatophenylsulfonyl isocyanate; 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-diisocyanatohexa Aliphatic polyisocyanate compounds such as noate; isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate (hydrogenated MDI), Lohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2-isocyanatoethyl) -4-dichlorohexene-1,2-dicarboxylate, 2,5-norbornane diisocyanate, 2,6-norbornane diisocyanate, etc. Examples include alicyclic polycyanate compounds. Of these, 4,4′-diphenylenemethane diisocyanate (MDI), isophorone diisocyanate (IPDI), and 4,4′-dicyclohexylmethane diisocyanate (hydrogenated MDI) are preferable from the viewpoint of controlling reactivity and imparting elastic modulus.

As the polyisocyanate compound (d _A ), a diisocyanate compound having two isocyanato groups in the molecule is preferable. However, an isocyanate group such as triphenylmethane triisocyanate is used as long as the polyurethane resin (A) does not gel. Polyisocyanates having 3 or more can also be used.

Polyisocyanate compound (d _A) may be used alone or in combination of plural kinds.

(Polyurethane prepolymer (A _p ))
The polyurethane resin (A) in the present invention is obtained by reacting at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ). The resulting polyurethane resin reacts with aliphatic polycarbonate polyol (a _A ), acidic group-containing polyol compound (b _A ), polyol (c _A ), polyisocyanate compound (d _A ), and chain extender (e _A ). It may be a polyurethane resin obtained. In the preparation of the polyurethane resin (A), at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), and a polyisocyanate compound (d _A ) are reacted to form a polyurethane prepolymer ( A _p ) can be obtained and then reacted with a chain extender (e _A ) to give a polyurethane resin (A). Here, the polyurethane prepolymer (A _p ) reacts the aliphatic polycarbonate polyol (a _A ), the acidic group-containing polyol compound (b _A ), the polyol (c _A ), and the polyisocyanate compound (d _A ). May be obtained.

In the preparation of the polyurethane prepolymer (A _p ), the total amount of the polyol component consisting of the aliphatic polycarbonate polyol (a _A ), the acidic group-containing polyol compound (b _A ), and the polyol (c _A ) optionally present is 100 parts by weight. In this case, the proportion of the aliphatic polycarbonate polyol (a _A ) is preferably 80 to 99 parts by weight from the viewpoint of the hardness of the coating film, and the proportion of the acidic group-containing polyol compound (b _A ) is determined according to dispersibility and coating. From the viewpoint of the water resistance of the membrane, it is preferably 1 to 20 parts by weight. The proportion of the aliphatic polycarbonate polyol (a _A ) is more preferably 85 to 98 parts by weight, particularly preferably 90 to 97 parts by weight, and the proportion of the acidic group-containing polyol compound (b _A ) is more preferably 2 to 98 parts by weight. 15 parts by weight, particularly preferably 3 to 10 parts by weight. The proportion of the polyol (c _A ) is preferably 0 to 30 parts by weight from the viewpoint of the hardness and dispersibility of the coating film. The aliphatic polycarbonate polyol (a _A ) and the acidic group-containing polyol compound (b _A ) Is preferably 0 to 19 parts by weight, more preferably 0 to 10 parts by weight, and particularly preferably 0 to 5 parts by weight.

The polyisocyanate compound (d _A ) is based on the number of moles of all hydroxyl groups in the polyol component consisting of the aliphatic polycarbonate polyol (a _A ), the acidic group-containing polyol compound (b _A ), and the polyol (c _A ) optionally present. The amount by which the molar ratio of the isocyanate groups of the polyisocyanate compound (d _A ) is 1.01 to 2.5 is preferable. If the ratio is in this range, it is easy to avoid an increase in the number of polyurethane prepolymers having no isocyanate groups at the molecular ends and an increase in the number of molecules that do not react with the chain extender, while the unreacted polyisocyanate. _A large amount of the compound (d _A ) does not remain in the reaction system. The ratio is more preferably 1.2 to 2.2, and still more preferably 1.2 to 2.0.

In the preparation of the polyurethane prepolymer (A _p ), a polyol component composed of an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ) and an optionally existing polyol (c _A ), and a polyisocyanate compound (d The reaction with _A ) may be carried out by reacting the aliphatic polycarbonate polyol (a _A ), the acidic group-containing polyol compound (b _A ), and the optionally existing polyol (c _A ) with the polyisocyanate compound (d _A ) in any order. Alternatively, two or more polyol components may be mixed and reacted with the polyisocyanate compound (d _A ), and then the remaining polyol component may be reacted. The reaction may be performed in an inert gas atmosphere or an air atmosphere.

In the reaction of the aliphatic polycarbonate polyol (a _A ), the acidic group-containing polyol compound (b _A ) and optionally the polyol (c _A ) with the polyisocyanate compound (d _A ), a catalyst may be used. it can. The catalyst is not particularly limited, and examples thereof include salts of metals and organic and inorganic acids such as tin catalysts (trimethyltin laurate, dibutyltin dilaurate, etc.) and lead catalysts (lead octylate, etc.), organometallic derivatives, Examples thereof include amine catalysts (triethylamine, N-ethylmorpholine, triethylenediamine, etc.), diazabicycloundecene catalysts, and the like. Among them, dibutyltin dilaurate is preferable from the viewpoint of reactivity.

The reaction temperature during the reaction of the aliphatic polycarbonate polyol (a _A ), the acidic group-containing polyol compound (b _A ) and optionally present polyol (c _A ) with the polyisocyanate compound (d _A ) is not particularly limited. For example, it can be 40-150 degreeC. If it is this range, coagulation | solidification of a raw material can be avoided easily, the viscosity of the polyurethane prepolymer obtained is also appropriate, and a side reaction can also be suppressed. The reaction may be performed in the absence of a solvent or by adding an organic solvent. Examples of the organic solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dioxane, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, N-ethylpyrrolidone, and ethyl acetate. Moreover, an organic solvent may be used individually by 1 type, or may use multiple types together. Among them, acetone, methyl ethyl ketone, and ethyl acetate are preferable because, in the preparation of the polyurethane resin (A), the polyurethane prepolymer (A _p ) is dispersed in water and a chain extension reaction is performed, and then can be easily removed by heating under reduced pressure. N-methylpyrrolidone and N-ethylpyrrolidone are preferable because they function as a film-forming aid when a coating film is formed from the aqueous polyurethane resin dispersion composition.

In the present invention, the average content of acidic groups in the polyurethane prepolymer (A _p ) is preferably 1.0 to 13.0% by weight. If it is this range, the dispersibility to an aqueous medium will be enough, favorable long-term storage stability can be obtained easily, and the water resistance of a coating film is also favorable. In the present specification, the “average content of acidic groups of the polyurethane prepolymer” means an organic solvent used in the preparation of the polyurethane prepolymer and a neutralizing agent for dispersing the polyurethane prepolymer in an aqueous medium. It is the average content of acidic groups in so-called solid content.

(Chain extender (e _A ))
The chain extender (e _A ) in the present invention is not particularly limited as long as it is a compound having two or more groups having reactivity with an isocyanato group in the molecule. For example, ethylenediamine, 1,4-tetramethylenediamine, 2-methyl-1,5-pentanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, 1,4-hexamethylenediamine, 3-aminomethyl-3,5,5-trimethylcyclohexylamine, 1 , 3-bis (aminomethyl) cyclohexane, xylylenediamine, piperazine, 2,5-dimethylpiperazine, amine compounds such as diethylenetriamine, triethylenetetramine, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6- Diol compounds such as hexanediol, polyethylene glycol Polyalkylene glycols represented by the water, and the like. Of these, primary diamine compounds are preferred. These may be used individually by 1 type and may use multiple types together.

The amount of the chain extender (e _A ) added is from the point of chain extension in the polyurethane prepolymer (A _p ) because it suppresses the decrease in the molecular weight of the resulting polyurethane resin (A) and obtains sufficient coating strength. It is preferable that it is below the equivalent of the isocyanato group. More preferably, it is 0.7-0.99 equivalent of an isocyanato group.

The chain extender (e _A ) may be added after the polyurethane prepolymer (A _p ) is dispersed in water or during the dispersion. Chain extension can also be carried out with water. In this case, water as a dispersion medium also serves as a chain extender.

Further, it is possible to optionally use the chain terminator with the chain extender (e _A), to adjust the molecular weight of the polyurethane resin (A). The terminal terminator is not particularly limited, and examples thereof include monoamines such as n-butylamine, di-n-butylamine and diethanolamine; monohydric alcohols such as ethanol, isopropanol and butanol. These may be used individually by 1 type and may use multiple types together.

(Polyurethane resin (A))
The polyurethane resin (A) can be obtained by reacting a polyurethane prepolymer (A _p ) with a chain extender (e _A ). The number average molecular weight of the polyurethane resin (A) can be 5,000 to 200,000. A polyurethane resin (A) can also be used individually by 1 type, and may use multiple types together.

(Aqueous medium)
In the present invention, the polyurethane resin (A) can be obtained as a dispersion in an aqueous medium. Examples of the aqueous medium include water and a mixed medium of water and a hydrophilic organic solvent. Examples of water include clean water, ion-exchanged water, distilled water, and ultrapure water. In consideration of availability and the effect of salt, particles are preferably ion-exchanged water. Is mentioned. Examples of hydrophilic organic solvents include lower monohydric alcohols such as methanol, ethanol, and propanol; polyhydric alcohols such as ethylene glycol and glycerin; N-methylmorpholine, dimethyl sulfoxide, dimethylformamide, N-methylpyrrolidone, N-ethylpyrrolidone, and the like. Aprotic hydrophilic organic solvents and the like. The amount of the hydrophilic organic solvent in the aqueous medium is preferably 0 to 20% by weight.

In the present invention, the dispersion of the polyurethane resin (A) is
A step (α1) of obtaining a polyurethane prepolymer (A _p );
A step (β1) of neutralizing the polyurethane prepolymer (A _p );
A step of dispersing the polyurethane prepolymer (A _p ) in an aqueous medium (γ1); and reacting the isocyanate group of the polyurethane prepolymer (A _p ) with the chain extender (e _A ) to produce an aqueous polyurethane resin (A) Obtaining step (δ1)
Can be manufactured.

The step (α1) for obtaining the polyurethane prepolymer (A _p ) is as described above.

As a neutralizing agent that can be used in the step (β1) of neutralizing the acidic group of the polyurethane prepolymer (A _p ), trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyl Organic amines such as diethanolamine, dimethylethanolamine, diethylethanolamine, N-methylmorpholine and pyridine; inorganic alkalis such as sodium hydroxide and potassium hydroxide, ammonia and the like. Among these, organic amines are preferable, more preferably tertiary amines, and still more preferably triethylamine.

In the step (γ1) of dispersing the polyurethane prepolymer (A _p ) in the aqueous medium, the method of dispersing the polyurethane prepolymer in the aqueous medium is not particularly limited, and is stirred by, for example, a homomixer or a homogenizer. in an aqueous medium, the aqueous medium process or during a homomixer or polyurethane prepolymer which is agitated by a homogenizer or the like (a _p), the solution is added to the polyurethane prepolymer (a _p) or polyurethane prepolymer (a _p) There is a method of adding.

In the step (δ1) of obtaining the aqueous polyurethane resin (A) by reacting the isocyanate group of the polyurethane prepolymer (A _p ) with the chain extender (e _A ), the reaction may be performed slowly under cooling, Alternatively, in some cases, the reaction may be promoted under heating conditions. The reaction temperature is preferably 0 to 80 ° C, more preferably 0 to 60 ° C.

And step (.beta.1) to neutralize the acid groups of the polyurethane prepolymer (A _p), the step of dispersing the polyurethane prepolymer (A _p) in the aqueous medium (.gamma.1) may be carried out simultaneously, also, the polyurethane prepolymer The step of dispersing (A _p ) in the aqueous medium (γ1) and the step of reacting with the chain extender (e _A ) to obtain the aqueous polyurethane resin (A) (δ1) may be performed simultaneously. The proportion of the polyurethane resin (A) in the dispersion is preferably 5 to 60% by weight, more preferably 20 to 50% by weight.

[Polyurethane resin (B)]
The polyurethane resin (B) of the present invention includes at least a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a linear chain having a number average molecular weight of 500 to 5,000. Alternatively, it is a polyurethane resin obtained by reacting a branched polyol (c _B ), a polyisocyanate compound (d _B ), and a chain extender (e _B ).

(Polycarbonate polyol (a _B ) having an alicyclic structure in the main chain)
The polycarbonate polyol (a _B ) having an alicyclic structure in the main chain in the present invention is not particularly limited as long as it has an alicyclic structure in the portion constituting the main chain other than the carbonate structure and the hydroxyl group. The alicyclic structure may be a single ring, a bicyclo ring or a condensed ring, and the ring may be interrupted by one or more heteroatoms such as oxygen, nitrogen, sulfur and the like. . The alicyclic structure preferably forms a ring with 4 to 7 carbon atoms. Further, in the main chain of (a _B ), a hydrocarbon group having a straight chain structure and / or a hydrocarbon group having a branched chain structure may coexist in addition to the alicyclic structure. By containing a polyurethane resin having an alicyclic structure in the main chain, the coating film obtained from the aqueous polyurethane resin dispersion composition of the present invention exhibits excellent hardness.

The number average molecular weight of the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain is not particularly limited, and the number average molecular weight is preferably 400 to 5,000. Within this range, the reactivity between the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain and the polyisocyanate compound (d _B ) is good, and the polycarbonate polyol having an alicyclic structure in the main chain ( It is easy to handle a _B ), and cracking can be suppressed when a coating film is formed. The number average molecular weight is preferably 400 to 4,000, and more preferably 400 to 3,000.

The polycarbonate polyol (a _B ) having an alicyclic structure in the main chain is not particularly limited. For example, a polycarbonate polyol obtained by reacting a polyol having an alicyclic structure in the main chain with a carbonate ester, And polycarbonate polyols obtained by reacting polyols having an alicyclic structure with other polyols and carbonates. Among these, from the viewpoint of dispersibility of the obtained aqueous polyurethane resin dispersion, a polycarbonate polyol obtained by reacting a polyol compound having an alicyclic structure in the main chain with another polyol and a carbonate is preferable.

  The polyol having an alicyclic structure in the main chain is not particularly limited. For example, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclopentanediol, In the main chain such as 1,4-cycloheptanediol, 2,5-bis (hydroxymethyl) -1,4-dioxane, 2,7-norbornanediol, tetrahydrofuran dimethanol, 1,4-bis (hydroxyethoxy) cyclohexane Examples include diols having an alicyclic structure, and among these, 1,4-cyclohexanedimethanol is preferable because of its availability.

Furthermore, as a raw material for the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, in addition to the polyol having an alicyclic structure in the main chain, a polyol other than the polyol having an alicyclic structure in the main chain is used in combination. You can also Examples of such polyols include 1,6-hexanediol, 1,5-pentanediol, 2-ethyl-1,6-hexanediol, 1,4-butanediol, 1,9-nonanediol, 3- Examples thereof include linear or branched aliphatic diols such as methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, diethylene glycol, triethylene glycol, and tetraethylene glycol.

In the present invention, the proportion of the alicyclic structure in the polycarbonate polyol (a _B) having an alicyclic structure in the main chain, in terms of points and handling properties of hardness, preferably 20 to 65% 30 It is more preferably 55%, and further preferably 40 to 55%.

  In the present invention, the ratio of the alicyclic structure refers to the portion constituting the alicyclic structure with respect to the molecular weight of the polycarbonate polyol (for example, in the case of 1,4-cyclohexanedimethanol, two hydrogen atoms were removed from cyclohexane. In the case of tetrahydrofuran dimethanol, it refers to the ratio of the total molecular weight of the portion obtained by removing two hydrogen atoms from tetrahydrofuran.

In synthesizing the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, a carbonate or phosgene can be used in the same manner as the aliphatic polycarbonate polyol (a _A ). Examples of the carbonate include aliphatic carbonates such as dimethyl carbonate and diethyl carbonate, aromatic carbonates such as diphenyl carbonate, and cyclic carbonates such as ethylene carbonate. Of these, dimethyl carbonate is preferred from the viewpoint of handling and easy removal of by-products. Further, in order to synthesize the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, the same temperature, pressure, time and other operation methods as those used for the synthesis of the aliphatic polycarbonate polyol (a _A ) are employed. be able to.

As a method for producing a polycarbonate polyol having an alicyclic structure in the main chain (a _B) it is not particularly limited, for example, to an ester interchange reaction between a polyol and a carbonate ester having an alicyclic structure in (1) the main chain (2) A method of producing by transesterifying a polyol other than a polyol having an alicyclic structure in the main chain with a polyol having a alicyclic structure in the main chain and a carbonate, (3 ) Manufactured by transesterifying a polycarbonate polyol obtained by transesterification of a polyol other than a polyol having an alicyclic structure in the main chain with a carbonate, and a polyol having an alicyclic structure in the main chain (4) Transesterification of polyols and carbonates having an alicyclic structure in the main chain (5) A polyol and carbonic acid having an alicyclic structure in the main chain, and a method of producing a polycarbonate polyol obtained by reacting with a polyol other than a polyol having an alicyclic structure in the main chain. Transesterification of polycarbonate polyol obtained by ester exchange reaction with ester and polycarbonate polyol obtained by ester exchange reaction of polyol and carbonate other than polyol having alicyclic structure in the main chain The method of manufacturing by making it be mentioned.

The polycarbonate polyol (a _B ) having an alicyclic structure in the main chain may be used alone or in combination of two or more.

(Acid group-containing polyol compound (b _B ))
The acidic group-containing polyol compound (b _B ) in the present invention refers to a compound having two or more hydroxyl groups and one or more acidic groups in the molecule, like the acidic group-containing polyol compound (b _A ). Examples of the acidic group include a carboxy group, a sulfonyl group, a phosphoric acid group, and a phenolic hydroxyl group, and a carboxy group is preferable. An acidic group-containing diol compound having two hydroxyl groups is preferred. Specific examples and preferred examples of the acidic group-containing polyol compound (b _A ) are applied to the acidic group-containing polyol compound (b _B ).

((Polyol (c _B ))
The polyol (c _B ) that can be used in the present invention is a linear or branched polyol having a number average molecular weight of 500 to 5,000. The number average molecular weight is preferably from 650 to 3,000, more preferably from 1,000 to 2,500, from the viewpoint of corrosion resistance of the metal in a salt spray test when a coating film of a metal substrate is used. As the polyol (c _B ), for example, polyester polyol, polyether polyol, polyether ester polyol, and acrylic polyol can be suitably used. Of these, polyether polyols are preferred because of their high hydrolysis resistance.

  Polyester polyol is not particularly limited, for example, polyethylene adipate diol, polybutylene adipate diol, polyethylene butylene adipate diol, polyhexamethylene isophthalate adipate diol, polyethylene succinate diol, polybutylene succinate diol, polyethylene sebacate diol, Examples thereof include polybutylene sebacate diol, poly-ε-caprolactone diol, poly (3-methyl-1,5-pentylene adipate) diol, polycondensate of 1,6-hexanediol and dimer acid.

The polyether polyol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol (PTMG), ethylene oxide and propylene oxide, and a random copolymer or block copolymer of ethylene oxide and butylene oxide. . Furthermore, a polyether polyester polyol having an ether bond and an ester bond can also be used. The polyol (c _B ) is preferably a polyether diol. More preferred is polytetramethylene glycol (PTMG).

Polyol (c _B) may be used alone or in combination of plural kinds.

In producing the polyurethane resin (B) of the present invention, as a polyol, a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5, A polyol (f _B ) other than a linear or branched polyol (c _B ) having 000 may be contained. Specific examples and preferred examples similar to those of the polyol (c _A ) are applied as (f _B ). The polyol (f _B ) is preferably a low molecular weight polyol having a number average molecular weight of 50 or more and less than 500.

(Polyisocyanate compound (d _B ))
The polyisocyanate compound (d _B ) that can be used in the present invention is not particularly limited as long as it has two or more isocyanato groups in the molecule. Specific examples and preferred examples of the polyisocyanate compound (d _A ) include Applied.

(Polyurethane prepolymer (B _p ))
The polyurethane resin (B) in the present invention comprises at least a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), a polyisocyanate compound (d _B ), and a chain extender ( e _B ) is a polyurethane resin obtained by reacting, and has a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5,000. It may be a polyurethane resin obtained by reacting a linear or branched polyol (c _B ), a polyisocyanate compound (d _B ) and a chain extender (e _B ). In the preparation of the polyurethane resin (B), at least a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a polyisocyanate compound (d _B ) are reacted. To obtain a polyurethane prepolymer (B _p ), which is then reacted with a chain extender (e _B ) to obtain a polyurethane resin (B). Here, the polyurethane prepolymer (B _p ) has a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5,000. It may be obtained by reacting a linear or branched polyol (c _B ) with a polyisocyanate compound (d _B ).

In the preparation of the polyurethane prepolymer (B _p ), a polyol component comprising a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), and an optionally existing polyol (c _B ) When the total amount of is 100 parts by weight, the proportion of the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain is preferably 60 to 95 parts by weight, more preferably from the viewpoint of the hardness of the coating film. 65-95 parts by weight, more preferably 65-90 parts by weight, particularly preferably 70-90 parts by weight, most preferably 75-85 parts by weight, and the proportion of acidic group-containing polyol compound (b _B ) Is preferably 10 to 40 parts by weight, more preferably 10 to 30 parts by weight, still more preferably 1 from the viewpoint of dispersibility and water resistance of the coating film. A 25 parts by weight, the proportion of the polyol _{(c B),} from the viewpoint of hardness and dispersibility of the coating, preferably from 0 to 30 parts by weight, the polycarbonate polyol in the total polyol component _{(a B)} and _{(b B} ) Is preferably 1 to 30 parts by weight, more preferably 1 to 25 parts by weight, and particularly preferably 1 to 15 parts by weight. The proportion of the polycarbonate polyol (a _B ) having an alicyclic structure in the main chain is more preferably 65 to 85 parts by weight, particularly preferably 75 to 85 parts by weight, and the proportion of the acidic group-containing polyol compound (b _B ). Is more preferably 10 to 30 parts by weight, particularly preferably 10 to 25 parts by weight, and the proportion of the polyol (c _B ) is more preferably 1 to 25 parts by weight, particularly preferably 3 to 15 parts by weight. .

The polyisocyanate compound (d _B ) is a polycarbonate polyol (a _B ) having an alicyclic structure in the main chain, an acidic group-containing polyol compound (b _B ), a linear chain having a number average molecular weight of 500 to 5000, which may be present, or The amount by which the ratio of the number of moles of isocyanate groups of the polyisocyanate compound (d _B ) to the number of moles of all hydroxyl groups of the polyol component consisting of the branched polyol (c _B ) is 1.01 to 2.5. Is preferred. Ratio, In this range, the number of the polyurethane prepolymer having no isocyanate group at the molecular terminal, to easily become many molecules that do not react with the chain extender can be avoided, the unreacted polyisocyanate compound (d _B ) Does not remain in the reaction system in large quantities. The ratio is more preferably 1.2 to 2.2, and still more preferably 1.2 to 2.0.

In the preparation of the polyurethane prepolymer (B _p ), the same order and reaction conditions as those for preparing the polyurethane prepolymer (A _p ) can be applied. Moreover, a catalyst can also be used like the case where a polyurethane prepolymer ( _Ap ) is manufactured.

In the present invention, the average content of acidic groups in the polyurethane prepolymer (B _p ) is preferably 2.0 to 13.0% by weight. If it is this range, the dispersibility to an aqueous medium is enough, favorable long-term storage stability can be obtained, and the water resistance of a coating film is also favorable.

(Chain extender (e _B ))
The chain extender (e _B ) in the present invention is not particularly limited as long as it is a compound having two or more groups having reactivity with an isocyanato group in one molecule. Specific examples of the chain extender (e _A ) and Preferred examples apply.

The amount of the chain extender (e _B ) added is from the point of chain extension in the polyurethane prepolymer (B _p ) because it suppresses the decrease in the molecular weight of the resulting polyurethane resin (B) and obtains sufficient coating strength. It is preferable that it is below the equivalent of the isocyanato group. More preferably, it is 0.7-0.99 equivalent of an isocyanato group.

The chain extender (e _B ) may be added after the polyurethane prepolymer (B _p ) is dispersed in water or during the dispersion. If necessary, it is also possible to use chain terminator together with the chain extender (e _B).

(Polyurethane resin (B))
The polyurethane resin (B) can be obtained by reacting a polyurethane prepolymer (B _p ) with a chain extender (e _B ). The number average molecular weight of the polyurethane resin (B) is usually about 5,000 to 200,000. A polyurethane resin (B) may be used individually by 1 type, respectively, and may use multiple types together, respectively. In the present invention, the polyurethane resin (B) can be obtained as a dispersion in an aqueous medium. Specific examples and preferred examples of the polyurethane resin (A) are applied to the type and amount of the aqueous medium.

In the present invention, the dispersion of the polyurethane resin (B) is
A step (α2) of obtaining a polyurethane prepolymer (B _p );
Neutralizing the polyurethane prepolymer (B _p ) (β2);
A step of dispersing the polyurethane prepolymer (B _p ) in an aqueous medium (γ2); and reacting the isocyanate group of the polyurethane prepolymer (B _p ) with the chain extender (e _B ) to form an aqueous polyurethane resin (B) It can be produced by the step (δ2) of obtaining a dispersion. Steps (α2), (β2), (γ2), and (δ2) apply the same reaction conditions, reagents, operation methods, and sequence as (α1), (β1), (γ1), and (δ1), respectively. be able to. The proportion of the polyurethane resin (B) in the dispersion is preferably 5 to 60% by weight, more preferably 20 to 50% by weight.

(Aqueous polyurethane resin dispersion composition)
In the aqueous polyurethane resin dispersion composition in the present invention, the polyurethane resin (A) and the polyurethane resin (B) are dispersed in an aqueous medium.

  The aqueous polyurethane resin dispersion composition in the present invention includes an aqueous polyurethane resin dispersion in which the polyurethane resin (A) is dispersed in an aqueous medium, and an aqueous polyurethane resin dispersion in which the polyurethane resin (B) is dispersed in an aqueous medium. It is preferable to manufacture each by mixing each of them. The mixing method is not particularly limited. For example, it is preferable to add the other aqueous polyurethane resin dispersion little by little while stirring one aqueous polyurethane resin dispersion.

  In the aqueous polyurethane resin dispersion composition, the mixing ratio of the polyurethane resin (A) and the polyurethane resin (B) is not particularly limited, and (A) / (B) is 3/97 to 75/25 in solid content ratio. It is preferable that the ratio is 5/95 to 80/20. For example, it can be in the range of 30/70 to 55/45. Within this range, even when the aqueous polyurethane resin dispersion composition is applied and dried at a low temperature such as 20 ° C., it is possible to obtain a coating film that does not easily crack.

  In addition to polyurethane resin (A) and polyurethane resin (B), other polyurethane resins, viscosity modifiers, stabilizers, antioxidants, antiseptics, fungicides, pH adjustments are included in the aqueous polyurethane resin dispersion composition. Additives such as agents and wettability improvers can be added.

[Coating composition and coating agent composition]
In the present invention, the coating composition and the coating composition containing the aqueous polyurethane resin dispersion composition include not only the paint and coating agent on the outermost surface of the coating but also a primer that forms an intermediate layer.

  In addition to the aqueous polyurethane resin dispersion of the present invention, other resins can be added to the coating composition and the coating agent composition. Examples of other resins include polyester resins, acrylic resins, polyether resins, polycarbonate resins, polyurethane resins, epoxy resins, alkyd resins, and polyolefin resins. These may be used individually by 1 type and may use multiple types together.

  The other resin preferably has one or more hydrophilic groups, and examples of the hydrophilic group include a hydroxyl group, a carboxy group, and a sulfonic acid group.

  The other resin is preferably at least one selected from the group consisting of a polyester resin, an acrylic resin, and a polyolefin resin.

  When the polyester resin and the acrylic resin have a hydroxyl group, a so-called urethane-modified polyester resin in which a part or all of the hydroxyl groups in the resin and a polyisocyanate compound are subjected to urethane reaction to extend these resins to increase the molecular weight. Alternatively, a urethane-modified acrylic resin may be used in combination.

  The polyester resin can be usually produced by an esterification reaction or an ester exchange reaction between an acid component and an alcohol component. As an acid component, the compound normally used in manufacture of a polyester resin can be used, For example, an aliphatic polybasic acid, an alicyclic polybasic acid, an aromatic polybasic acid etc. are mentioned.

  The hydroxyl value of the polyester resin is preferably 10 to 300 mgKOH / g, more preferably 50 to 250 mgKOH / g, and still more preferably 80 to 180 mgKOH / g. The acid value of the polyester resin is preferably 1 to 200 mgKOH / g, more preferably 15 to 100 mgKOH / g, and further preferably 25 to 60 mgKOH / g. The weight average molecular weight of the polyester resin is preferably 500 to 500,000, more preferably 1,000 to 300,000, and still more preferably 1,500 to 200,000. In this specification, the weight average molecular weight is a value measured by gel permeation chromatography (polystyrene conversion).

  As the acrylic resin, a hydroxyl group-containing acrylic resin is preferable. Hydroxyl group-containing acrylic resin is a hydroxyl group-containing polymerizable unsaturated monomer and other polymerizable unsaturated monomer copolymerizable with this monomer, for example, solution polymerization method in organic solvent, emulsion polymerization method in water, etc. It can be produced by copolymerization by a known method.

  The hydroxyl group-containing polymerizable unsaturated monomer is not particularly limited as long as it is a compound having at least one hydroxyl group and one polymerizable unsaturated bond in one molecule. 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl Monoesterified products of (meth) acrylic acid such as (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and dihydric alcohols having 2 to 8 carbon atoms; these monoesterified products Ε-caprolactone modified product of: N-hydroxymethyl (meth) acrylamide; allyl alcohol; (meth) acrylate having a polyoxyethylene chain whose molecular terminal is a hydroxyl group.

  The hydroxyl group-containing acrylic resin preferably has a cationic functional group. The hydroxyl group-containing acrylic resin having a cationic functional group uses, for example, a polymerizable unsaturated monomer having a cationic functional group such as a tertiary amino group or a quaternary ammonium base as one kind of the polymerizable unsaturated monomer. Can be manufactured.

  The hydroxyl value of the hydroxyl group-containing acrylic resin is preferably 1 to 200 mgKOH / g, more preferably 2 to 100 mgKOH / g, and even more preferably 3 to 60 mgKOH / g, from the viewpoints of storage stability and water resistance of the resulting coating film. .

  When the hydroxyl group-containing acrylic resin has an acid group such as a carboxyl group, the acid value of the hydroxyl group-containing acrylic resin is preferably 1 to 200 mgKOH / g, and preferably 2 to 150 mgKOH from the viewpoint of water resistance of the resulting coating film. / G is more preferable, and 5 to 100 mgKOH / g is more preferable.

  The weight average molecular weight of the hydroxyl group-containing acrylic resin is preferably 1,000 to 200,000, more preferably 2,000 to 100,000, and still more preferably 3,000 to 50,000.

  Examples of the polyether resin include polymers or copolymers having an ether bond, and polyoxyethylene polyether, polyoxypropylene polyether, polyoxybutylene polyether, aromatic such as bisphenol A or bisphenol F. Examples thereof include polyethers derived from polyhydroxy compounds.

  Examples of the polycarbonate resin include polymers derived from bisphenol compounds, such as bisphenol A / polycarbonate.

  Examples of the polyurethane resin include resins having a urethane bond obtained by reaction of various polyol components such as acrylic polyol, polyester polyol, polyether polyol, and polycarbonate polyol with a polyisocyanate compound.

  Examples of the epoxy resin include a resin obtained by a reaction between a bisphenol compound and epichlorohydrin. Examples of the bisphenol compound include bisphenol A and bisphenol F.

  Alkyd resins include polybasic acids such as phthalic acid, terephthalic acid, and succinic acid, polyhydric alcohols, fats and oils and fatty acids (soybean oil, linseed oil, coconut oil, stearic acid, etc.) and natural resins (rosin, succinic acid). Etc.) and the like.

  As the polyolefin resin, a polyolefin resin obtained by polymerizing or copolymerizing an olefin monomer with another monomer in accordance with a normal polymerization method is dispersed in water using an emulsifier, or the olefin monomer is appropriately replaced with another monomer. And a resin obtained by emulsion polymerization. In some cases, a so-called chlorinated polyolefin-modified resin in which the polyolefin resin is chlorinated may be used.

  Examples of the olefin monomer include ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-decene, Examples include α-olefins such as 1-dodecene and styrenes; conjugated dienes such as butadiene, ethylidene norbornene, dicyclopentadiene, and 1,5-hexadiene, and nonconjugated dienes. These monomers may be used alone. Two or more kinds may be used in combination.

  Examples of other monomers copolymerizable with olefinic monomers include vinyl acetate, vinyl alcohol, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, and the like. May be used alone or in combination of two or more.

  The coating composition and the coating composition of the present invention contain a curing agent to provide a coating film or a multilayer coating film obtained by using the coating composition or the coating composition, water resistance of the coating film, etc. Can be improved.

  Examples of the curing agent include amino resins, polyisocyanate compounds, blocked polyisocyanate compounds, melamine resins, carbodiimides, and the like. A hardening | curing agent may be used independently and may use 2 or more types together.

  Examples of the amino resin include a partial or completely methylolated amino resin obtained by a reaction between an amino component and an aldehyde component. Examples of the amino component include melamine, urea, benzoguanamine, acetoguanamine, steroguanamine, spiroguanamine, dicyandiamide and the like. Examples of the aldehyde component include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and the like.

  Examples of the polyisocyanate compound include compounds having two or more isocyanato groups in one molecule, such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate. Examples of the blocked polyisocyanate compound include those obtained by adding a blocking agent to the polyisocyanate group of the aforementioned polyisocyanate compound. Examples of the blocking agent include phenols such as phenol and cresol, methanol, and ethanol. Aliphatic alcohols such as dimethyl malonate, active methylenes such as acetylacetone, mercaptans such as butyl mercaptan and dodecyl mercaptan, acid amides such as acetanilide and acetate amide, lactams such as ε-caprolactam and δ-valerolactam Blocking of acid imides such as succinimide and maleic imide, oximes such as acetoaldoxime, acetone oxime and methylethylketoxime, and amines such as diphenylaniline, aniline and ethyleneimine Agents.

  Examples of the melamine resin include methylol melamines such as dimethylol melamine and trimethylol melamine; alkyl etherified products or condensates of these methylol melamines; condensates of alkyl etherified products of methylol melamine, and the like.

  Coloring pigments, extender pigments and glitter pigments can be added to the coating composition and coating agent of the present invention.

  Examples of the coloring pigment include titanium oxide, zinc white, carbon black, molybdenum red, Prussian blue, cobalt blue, azo pigment, phthalocyanine pigment, quinacridone pigment, isoindoline pigment, selenium pigment, and perylene pigment. These may be used alone or in combination of two or more. In particular, it is preferable to use titanium oxide and / or carbon black as the color pigment.

  Examples of extender pigments include clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white. These may be used alone or in combination of two or more. In particular, barium sulfate and / or talc are preferably used as extender pigments, and barium sulfate is more preferably used.

  Examples of the bright pigment include aluminum, copper, zinc, brass, nickel, aluminum oxide, mica, aluminum oxide coated with titanium oxide and iron oxide, mica coated with titanium oxide and iron oxide, and the like.

  The coating composition and the coating composition of the present invention are usually a thickener, a curing catalyst, an ultraviolet absorber, a light stabilizer, an antifoaming agent, a plasticizer, a surface conditioner, an anti-settling agent, etc., if necessary. These coating additives can be contained alone or in combination of two or more.

  There is no restriction | limiting in particular in the manufacturing method of the coating composition of this invention, and a coating agent composition, A well-known manufacturing method can be used. In general, a coating composition and a coating composition are produced by mixing an aqueous polyurethane resin dispersion and the above-mentioned various additives, adding an aqueous medium, and adjusting the viscosity according to the coating method. .

  The coating composition and the coating agent composition of the present invention can be applied to a substrate and then cured to form a coating film to obtain a coated substrate. The coated substrate of the coating composition or the coated substrate of the coating agent is not particularly limited, and examples thereof include metals, plastics, and inorganic materials. The coating method of the coating composition or the coating method of the coating agent composition is not particularly limited, and examples thereof include bell coating, spray coating, roll coating, shower coating, and dip coating. For curing the coating composition and the coating agent after application, a general curing method such as room temperature drying, hot air drying, or heat drying can be employed.

  The aqueous polyurethane resin dispersion composition of the present invention, and the coating composition and coating agent composition containing this composition are weak substrates such as thermoplastic resins, rubbers, elastomers, and wood, which are easily deformed or discolored at high temperatures. A particularly excellent effect is exerted on a flexible base material (for example, a metal or plastic thin plate or film) that is deformed by stress. In particular, when applied to a metal substrate, a coating film having an effect of preventing metal corrosion and a flexibility capable of avoiding the occurrence of cracks in bending is provided.

[Composition for synthetic leather]
The present invention also relates to a composition for synthetic leather containing an aqueous polyurethane resin dispersion composition.

  As the synthetic leather composition of the present invention, in addition to the aqueous polyurethane resin dispersion of the present invention, a light stabilizer, a heat stabilizer, an ultraviolet absorber, an antioxidant, an antiseptic, an antifungal agent, an antistatic agent, Commonly used additives such as flame retardants, antiblocking agents, fillers, thickeners, water, dyes, pigments, pigment dispersants and the like can be added.

  When the composition for synthetic leather of the present invention is applied to synthetic leather, the fiber base material and the composition for synthetic leather are used by a known method such as a dry lamination method, a wet lamination method, an impregnation method, or a coating method. It can be applied by laminating the obtained urethane film or impregnating the fiber base material with the composition for synthetic leather. When using a dry lamination method or a wet lamination method, a synthetic leather composition is applied onto a release paper with a knife coater, etc., dried, and then optionally laminated to a fiber substrate using an adhesive or the like. And heat treatment to obtain a synthetic leather. When using the impregnation method, a synthetic leather composition diluted to a solid content concentration of 10 to 30% by weight is impregnated into a raised woven fabric, squeezed with a mangle, etc., and then heat treated to obtain a synthetic leather. be able to. Furthermore, in the coating method, a synthetic leather composition can be obtained by laminating a synthetic leather composition on a fiber substrate using a knife coater or a roll coater and then heat-treating the composition.

  Examples of the fiber base material include woven fabric, non-woven fabric, and knitted fabric. The fiber base material may have one surface or both surfaces raised.

  The synthetic leather to which the composition for synthetic leather of the present invention is applied may be subjected to embossing such as an embossing roll or wrinkle processing, and a top coat layer may be further formed on the surface of the synthetic leather. Synthetic leather to which the composition for synthetic leather of the present invention is applied is excellent in resistance to oleic acid, so products that are easily touched by hand such as sofas, chairs, vehicle interior materials, vehicle seat skin materials, and products that easily adhere to sweat. Excellent for use.

[Synthesis Example 1]
(Production of aqueous polyurethane resin dispersion containing polyurethane resin (A))
In a reaction apparatus equipped with a stirrer and a heater, ETERRNACOLL (registered trademark) UH200 (manufactured by Ube Industries; number average molecular weight 2000; hydroxyl value 57 mgKOH / g; 1,6-hexanediol and carbonate ester as (a _A ) polycarbonate diols obtained by reacting, 300 g) and, and _{(b a)} as 2,2-dimethylol propionic acid (16.3 g), and isophorone diisocyanate (85.6 g) as _{(d a),} N- The mixture was heated in ethyl pyrrolidone (135 g) in the presence of dibutyltin dilaurate (0.6 g) at 80 to 90 ° C. for 5 hours in a nitrogen atmosphere. The reaction mixture was cooled to 80 ° C., triethylamine (12.3 g) was added to and mixed with the mixture, and the mixture was added to water (816 g) under strong stirring. Then, to obtain a _{(e A)} 35 wt% of 2-methyl-1,5-pentanediamine aqueous solution (34.7 g) was added as a solid content 30 wt% of aqueous polyurethane resin dispersion (A).

[Synthesis Example 2]
(Production of aqueous polyurethane resin dispersion containing polyurethane resin (B-1))
In a reaction apparatus equipped with a stirrer and a heater, ETERRNACOLL UC100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1030; hydroxyl value 109 mgKOH / g; 1,4-cyclohexanedimethanol and carbonate ester are reacted as (a _B ) It is allowed to polycarbonate diol obtained, the ratio 49.5 percent of alicyclic structure, 85.0 g) and, and _{(c B)} PTMG (number average molecular weight 2030,14.9G) as 2,2 as _{(b B)} -Dimethylolpropionic acid (12.1 g) and hydrogenated MDI (91.1 g) as (d _B ) in N-ethylpyrrolidone (146 g) in the presence of dibutyltin dilaurate (0.2 g), nitrogen It heated at 80--90 degreeC for 6 hours under atmosphere. The NCO group content at the end of the urethanization reaction was 4.5% by weight. The reaction mixture was cooled to 80 ° C., and 239 g was extracted from the mixture in which triethylamine (8.9 g) was added and mixed, and added to water (310 g) under strong stirring. Subsequently, 35% by weight 2-methyl-1,5-pentanediamine aqueous solution (41.0 g) was added as (e _B ) to obtain an aqueous polyurethane resin dispersion (B-1) having a solid content of 30% by weight.

[Synthesis Example 3]
(Production of aqueous polyurethane resin dispersion containing polyurethane resin (B-2))
In a reaction apparatus equipped with a stirrer and a heater, ETERRNACOLL UM90 (3/1) (manufactured by Ube Industries, Ltd .; number average molecular weight 916; hydroxyl value 122 mgKOH / g; polyol component 1,4-cyclohexane di) as (a _B ) (B _B ): polycarbonate diol obtained by reacting a polyol mixture of a molar ratio of methanol: 1,6-hexanediol = 3: 1 and a carbonic acid ester, alicyclic structure ratio 42%, 350 g) 2,2-dimethylolpropionic acid (62.6 g) and isophorone diisocyanate (336 g) as (d _B ) in N-ethylpyrrolidone (315 g) in the presence of dibutyltin dilaurate (0.6 g) in a nitrogen atmosphere Under heating at 80-90 ° C. for 3.5 hours. The NCO group content at the end of the urethanization reaction was 7.5% by weight. The reaction mixture was cooled to 80 ° C., triethylamine (47.1 g) was added to and mixed with this, and the mixture was added to water (375 g) under strong stirring. Subsequently, 35 wt% 2-methyl-1,5-pentanediamine aqueous solution (32.3 g) was added as (e _B ) to obtain an aqueous polyurethane resin dispersion (B-2) having a solid content of 30 wt%.

[Synthesis Example 4]
(Production of aqueous polyurethane resin dispersion containing polyurethane resin (C))
In a reactor equipped with stirrer and heater, and _{(a C)} the number and polytetramethylene glycol 300g of average molecular weight 2000 as, _{(b C)} as 2,2-dimethylol propionic acid (16.3 g), ( As d _C ), isophorone diisocyanate (85.6 g) was heated in N-ethylpyrrolidone (135 g) in the presence of dibutyltin dilaurate (0.6 g) at 80 to 90 ° C. for 5 hours. The reaction mixture was cooled to 80 ° C., triethylamine (12.3 g) was added to and mixed with the mixture, and the mixture was added into water (816 g) with vigorous stirring. Then, to obtain a _{(e C)} 35 wt% of 2-methyl-1,5-pentanediamine aqueous solution (34.7 g) was added as a solid content 30 wt% of aqueous polyurethane resin dispersion (C).

[Synthesis Example 5]
(Production of aqueous polyurethane resin dispersion containing polyurethane resin (D))
In a reactor equipped with stirrer and heater, _{(a D)} and number polyester diol 300g of average molecular weight 2000 obtained from butanediol and neopentyl glycol and adipic acid as, as _{(b D)} 2,2-di Methylolpropionic acid (16.3 g) and isophorone diisocyanate (85.6 g) as (d _D ) in N-ethylpyrrolidone (135 g) in the presence of dibutyltin dilaurate (0.6 g) under a nitrogen atmosphere, Heated at 80-90 ° C. for 5 hours. The reaction mixture was cooled to 80 ° C., triethylamine (12.3 g) was added to and mixed with the mixture, and the mixture was added to water (816 g) under strong stirring. Then, to obtain a _{(e D)} 35% by weight of 2-methyl-1,5-pentanediamine aqueous solution (34.7 g) was added as a solid content 30 wt% of aqueous polyurethane resin dispersion (D).

[Examples 1-12, Comparative Examples 1-5]
Each aqueous polyurethane resin dispersion was added little by little with stirring at the ratio described in Table 1, and mixed to obtain an aqueous polyurethane resin dispersion composition (solid content 30% by weight).

The bending test was performed as follows.
[Sample preparation]
0.1% by weight of a wettability improver ("BYK-348" manufactured by Big Chemie Japan Co., Ltd., polyether-modified siloxane) was added to the aqueous polyurethane resin dispersion compositions obtained in each of Examples and Comparative Examples. , And a coating agent was obtained. The coating agent was uniformly applied to the surface of a soft polyvinyl chloride sheet having a thickness of 2 mm so that the film thickness after drying was about 10 μm. Subsequently, it dried at 80 degreeC for 1 hour, and the test piece was obtained. The obtained test piece was visually evaluated for the presence or absence of cracks on the coating film surface based on the JIS K-5600 bending resistance test method (cylindrical mandrel method) using a cylindrical bending tester. The mandrel diameter was 2 mm. The results are shown in Table 1.

The pen drum hardness was measured as follows.
[Pen drum hardness sample preparation]
The aqueous polyurethane resin dispersion composition obtained in each Example and Comparative Example was uniformly applied on a glass plate so that the film thickness after drying was about 20 μm. Subsequently, after drying overnight at room temperature, it was dried at 60 ° C. for 1 hour and at 120 ° C. for 1 hour to obtain a coating film dried at 120 ° C. The aqueous polyurethane resin dispersion composition obtained in each Example and Comparative Example was uniformly applied on a glass plate so that the film thickness after drying was about 20 μm. Subsequently, it was dried at 20 ° C. for 1 week to obtain a coating film dried at 20 ° C.
[Measurement of pen drum hardness]
In the laminate of the glass plate and the polyurethane resin coating film obtained above, the pen drum hardness of the resin coating film was measured using a pen drum type hardness meter (Pendrum Hardness Tester manufactured by BYK-Gardner GmbH) with an amplitude attenuation time of 3 The average value was calculated by measuring at several points. The larger the amplitude decay time, the greater the hardness. The results are shown in Table 1.

The presence or absence of cracks on the surface of the wood plywood coating film was visually evaluated as follows.
The aqueous polyurethane resin dispersion composition obtained in each Example and Comparative Example was uniformly applied on a wood plywood (floor material of birch plywood) so that the film thickness after drying was about 20 μm. Subsequently, it was dried at 20 ° C. for 1 week to form a coating film on the surface of the wood plywood. The presence or absence of cracks on the coating surface was visually evaluated.

[Solvent resistance]
Solvent resistance was evaluated as follows.
Absorbent cotton cut into a size of 1 cm ² soaked in methyl ethyl ketone (MEK) was pressed against the surface of the sample and rubbed 100 times, and the change of the coating film was observed visually.
○: Almost no change Δ: Part of the coating film peels off ×: The coating film peels off completely

From Table 2, the example which combined polyurethane resin (A) and polyurethane resin (B-2) (In the Example of Table 2, polyurethane resin (A) / polyurethane resin (B-2) is 5 / 95-75. / 25, Examples 1 to 9), it was found that the pendrum hardness of the coating film on the glass plate was relatively high, there was no crack after the bending test, and no crack was generated even on the wood plywood. In addition, when the polyurethane resin (A) / polyurethane resin (B-2) is 5/95 to 50/50, the pen drum hardness of the coating film on the glass plate is higher and there is no crack after the bending test. It was found that cracks did not occur even on wood plywood. Furthermore, when the polyurethane resin (A) / polyurethane resin (B-2) is 20/80 to 50/50, it exhibits high hardness even when dried at a low temperature (20 ° C.), and cracks after the bending test also occur. It was also found that no cracks occurred on the wood plywood. On the other hand, in Comparative Example 1 containing no polyurethane resin (A), cracks occurred after the bending test, and when dried at a low temperature (20 ° C.), the hardness of the coating film on the glass plate was low, and cracks were observed on the wood plywood. Occurred. Cracks in the coating film were observed in the pen drum low temperature bending test. Moreover, in the comparative example 2 which does not contain a polyurethane resin (B-2), the pen drum hardness of the coating film on a glass plate was low.
On the other hand, in Examples 10-12 which combined polyurethane resin (B-1) instead of polyurethane resin (B-2), the solubility was suppressed in the coating film to methyl ethyl ketone, and the solvent resistance was good ( Especially Example 7). It turns out that the solvent resistance of Examples 10-12 is improving compared with the comparative examples 4 and 5 which replaced with polyurethane resin (A) and combined polyurethane resin (C) and (D). It was.

A bending test, an evaluation of solvent resistance, and a salt spray test were performed using the samples prepared as follows.
[Sample preparation]
A No. 18 bar coater was prepared by applying the aqueous polyurethane resin dispersion composition obtained in each Example and Comparative Example to a steel plate (SPCC-SD) 0.8 mm thick, 70 mm wide and 150 mm long degreased using toluene. It applied using. Then, the steel plate was heat-dried for 4 minutes in a 180 degreeC hot air dryer, and the sample which has a polyurethane resin coating film on a steel plate was created.

[Solvent resistance]
Solvent resistance was evaluated as follows.
Absorbent cotton cut into a size of 1 cm ² soaked in methyl ethyl ketone (MEK) was pressed against the surface of the sample and rubbed 100 times, and then the change in the coating film was observed.
[Low temperature flexibility]
The sample was cooled for 10 minutes in a low temperature bath at -15 ° C. Thereafter, the sample was taken out and immediately bent using a vise at the center in the length direction. At the time of bending, a 4.8 mm gap was formed on the bent plate using a spacer having a thickness of 4.8 mm.
[Salt spray resistance]
In accordance with JIS K 5600-7-9, a salt spray test was conducted using a combined cycle corrosion tester. The test piece was cut into an X shape with a cutter knife. 5% saline solution was used for the test, and the test cycle was 15 cycles (120 hours) with salt spray for 2 hours at 35 ° C, drying for 4 hours at 60 ° C, and wet 50 ° C and 95% RH for 2 hours. It was. After the test, the state of corrosion (rust) in the part without cut (planar part) was visually observed from the top of the coating film, and the progress of corrosion from the cut part was measured. A schematic diagram showing the state of the surface of the test piece is shown in FIG. The progression length of corrosion was measured in mm as indicated by reference numeral 4 in the vertical direction in which rust progressed from the cut portion indicated by reference numeral 2. The state of the surface of a test piece is shown to Fig.2 (a)-(j). The test pieces of Examples 6 to 8 and 10 to 12 correspond to (a) to (c) and (f) to (h), respectively, and the test pieces of Comparative Examples 2 to 5 respectively have (d) to (d) e) corresponds to (i) to (j). Table 1 shows the state of corrosion of the flat portion and the progress of corrosion.
In addition, the corrosion state of the plane portion was evaluated according to the following criteria.
○: There is almost no rust.
Δ: There is a little rust.
X: There is much rust.

From Table 3, the Example which combined the polyurethane resin (A) and the polyurethane resin (B-1) (In an Example, polyurethane resin (A) / polyurethane resin (B-1) is 40 / 60-60 / 40, implementation. In Examples 10 to 12), all of the solvent resistance, the low temperature flexibility and the salt spray resistance were good results (see (f) to (h) in FIG. 2). Although Examples 6-8 which used the polyurethane resin (B-2) which is a polyurethane resin which does not contain (c _B ) instead of the polyurethane resin (B-1) showed relatively good salt spray resistance, Compared with Examples 10-12, the rust from a notch part has developed a little (refer (a)-(c) of FIG. 2).
On the other hand, Comparative Example 2 containing neither polyurethane resin (B-1) nor (B-2) but containing only polyurethane resin (A) has developed corrosion even in the plane portion, and is resistant to salt spray. Was bad (see FIG. 2D). In Comparative Example 3 containing no polyurethane resin (A), cracks in the coating film were observed in the low-temperature bending test, and almost the entire surface was corroded black (see FIG. 2 (e)). Further, in Comparative Example 4 using the polyurethane resin (C) instead of the polyurethane resin (A), rust was generated on the entire plane portion of the test piece in the salt spray test (see (i) in FIG. 2). In Comparative Example 5 using the polyurethane resin (D) instead of (A), cracking of the coating film was observed in the low-temperature bending test, and rust was generated on the entire flat portion of the test piece in the salt spray test ( (See (j) of FIG. 2).

  The aqueous polyurethane resin dispersion composition of the present invention is easily deformed and discolored at a high temperature, and when applied to a substrate made of a thermoplastic resin, rubber, elastomer, wood, etc. Even when the coating film is dried at a low temperature of 20 ° C., a coating film exhibiting high hardness can be obtained, which is effective in protecting these substrates. The aqueous polyurethane resin dispersion composition of the present invention can be applied not only to plastics, inorganic materials, etc., but also to synthetic leather. In addition, the aqueous polyurethane resin dispersion composition of the present invention is resistant to cracking during bending, especially when coated on the surface of a metal substrate, has excellent solvent resistance, and prevents metal corrosion in a salt spray test. it can. INDUSTRIAL APPLICABILITY The present invention is very useful industrially in the field of paints applied to materials such as metals and plastics, and in the field of materials in contact with salt water.

DESCRIPTION OF SYMBOLS 1 ... Steel plate 2 ... Notch 3 ... Plane part 4 ... Progression length of corrosion from notch part 5 ... Corrosion part

Claims (16)

An aqueous polyurethane resin dispersion composition in which at least a polyurethane resin (A) and a polyurethane resin (B) are dispersed in an aqueous medium,
The polyurethane resin (A) is obtained by reacting at least an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), a polyisocyanate compound (d _A ), and a chain extender (e _A ). Polyurethane resin,
Polyurethane resin (B) is at least obtained by reacting a polyol with a carbonate ester having an alicyclic structure in the main chain polycarbonate polyol (a _B), an acidic group-containing polyol compound (b _B), the polyisocyanate compound ( d _B ), and a polyurethane resin obtained by reacting a chain extender (e _B ),
An aqueous polyurethane resin dispersion composition. Polyurethane resin (A) is a polyol (c _A ) other than aliphatic polycarbonate polyol (a _A ), acidic group-containing polyol compound (b _A ), aliphatic polycarbonate polyol (a _A ), and acidic group-containing polyol compound (b _A ). ), A polyisocyanate compound (d _A ), and a chain extender (e _A ), the aqueous polyurethane resin dispersion composition according to claim 1. A polyurethane resin (A) reacts an aliphatic polycarbonate polyol (a _A ) and an acidic group-containing polyol compound (b _A ) with a polyisocyanate compound (d _A ) to obtain a polyurethane prepolymer (A _p ), Next, the aqueous polyurethane resin dispersion composition according to claim 1, which is a polyurethane resin obtained by reacting a polyurethane prepolymer (A _p ) with a chain extender (e _A ). The polyurethane resin (A) is an aliphatic polycarbonate polyol (a _A ), an acidic group-containing polyol compound (b _A ), and a polyol (c _A ) other than the aliphatic polycarbonate polyol (a _A ) and the acidic group-containing polyol compound (b _A ). ) And a polyisocyanate compound (d _A ) to obtain a polyurethane prepolymer (A _p ), and then a polyurethane obtained by reacting the polyurethane prepolymer (A _p ) with a chain extender (e _A ) The aqueous polyurethane resin dispersion composition according to claim 2, which is a resin. Polyurethane resin (B) is a polycarbonate polyol (a _B ) obtained by reacting a polyol having an alicyclic structure in the main chain with a carbonic ester , an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5 Polyurethane resin obtained by reacting a linear or branched polyol having 1,000,000 (excluding polycarbonate polyol) (c _B ), a polyisocyanate compound (d _B ), and a chain extender (e _B ) The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 4, wherein Polyurethane resin (B) is a polycarbonate polyol (a _B ) and an acidic group-containing polyol compound (b _B ) obtained by reacting a polyol having a cycloaliphatic structure in the main chain with a carbonate , and a polyisocyanate compound (d _B) and to give a reacted polyurethane prepolymer (B _p) and then, a polyurethane resin obtained by reacting a polyurethane prepolymer (B _p) and chain extender (e _B), claim 1 The water-based polyurethane resin dispersion composition as described in any one of -4. Polyurethane resin (B) is a polycarbonate polyol (a _B ) obtained by reacting a polyol having an alicyclic structure in the main chain with a carbonic ester , an acidic group-containing polyol compound (b _B ), and a number average molecular weight of 500 to 5 , 000 having a linear or branched polyol (excluding polycarbonate polyol) (c _B ) and a polyisocyanate compound (d _B ) to obtain a polyurethane prepolymer (B _p ), Next, the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 5, which is a polyurethane resin obtained by reacting a polyurethane prepolymer (B _p ) with a chain extender (e _B ). The linear or branched polyol (c _B ) having a number average molecular weight of 500 to 5,000 is a polyether polyol having no alicyclic structure in the main chain. The aqueous polyurethane resin dispersion composition according to Item.   The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 8, wherein the mixing ratio of the polyurethane resin (A) and the polyurethane resin (B) is 3/97 to 75/25 in terms of solid content ratio. object.   The water-based polyurethane resin dispersion composition of Claim 9 whose mixing ratio of a polyurethane resin (A) and a polyurethane resin (B) is 5 / 95-80 / 20 by solid content ratio.   The aqueous polyurethane resin dispersion composition according to claim 10, wherein the mixing ratio of the polyurethane resin (A) and the polyurethane resin (B) is 30/70 to 55/45 in terms of solid content.   The coating agent composition containing the water-based polyurethane resin dispersion composition as described in any one of Claims 1-11.   The coating composition containing the aqueous polyurethane resin dispersion composition as described in any one of Claims 1-11.   The coating composition according to claim 13, which is for metal coating.   The composition for synthetic leather containing the water-based polyurethane resin dispersion composition as described in any one of Claims 1-11.   It is a manufacturing method of the water-based polyurethane resin dispersion composition as described in any one of Claims 1-11, Comprising: The water-based polyurethane resin dispersion in which the polyurethane resin (A) is disperse | distributing in the aqueous medium, and polyurethane resin (B) The manufacturing method including the process of mixing with the aqueous | water-based polyurethane resin dispersion which is disperse | distributing in the aqueous medium.