JP2023151237A - Aqueous urethane resin dispersion and coating material composition, and coating film of the same - Google Patents

Abstract

To provide an aqueous urethane resin dispersion composition which enables formation of a coating film in low temperature drying at 20-100°C, and enables formation of a coating film having adhesion, hardness and flexibility.SOLUTION: An aqueous polyurethane resin dispersion composition contains a polyurethane resin and an aqueous medium, wherein the polyurethane resin has a structural unit derived from polyester polyol (A) containing polyol (Aa) and a dicarboxylic acid (Ab) as components, a structural unit derived from polyether polyol (G) and a structural unit derived from polyisocyanate (B), an aromatic ring is contained in the polyurethane resin, the content of the aromatic ring is 4-18 mass% in the polyurethane resin, the content of an ether bond is 0.5-10 mass%, and the aqueous polyurethane resin dispersion can contribute to SDGs (Sustainable Development Goals).SELECTED DRAWING: None

Description

The present invention relates to an aqueous urethane resin dispersion.

Water-based polyurethane resin dispersion compositions can provide coating films with adhesive properties, abrasion resistance, and rubber-like properties, and can reduce volatile organic matter compared to conventional solvent-based polyurethanes, so they can be used as environmentally friendly materials. This is a material that is increasingly replacing polyurethane-based polyurethanes.
Aqueous polyurethane resin dispersion compositions are used, for example, as anti-fracture materials for use as intermediate coatings in the exterior of automobiles. When the aqueous polyurethane resin dispersion composition is used as a film, paint or coating material, or fracture-resistant material, it is applied to a substrate using a coating device such as a bar coater, roll coater, or air spray. . A coating film is formed on the substrate by heating and drying the applied aqueous polyurethane resin dispersion composition.

It is known that a coating film obtained by applying an aqueous urethane resin dispersion made from polycarbonate polyol as a raw material has excellent light resistance, heat resistance, hydrolysis resistance, and oil resistance (see Patent Document 1).

On the other hand, coating films obtained from aqueous urethane resin dispersions using polyester polyols are known to have excellent adhesion to various substrates (Patent Documents 2 to 4). Patent Document 2 describes a compound in which a mixture of two types of polyol components, for example, a polyester polyol and a polyether polyol, is used as the polyol component, and further has at least one group capable of reacting with at least one acid group and an isocyanate group; It has been described that hydroxy-functional polyester-polyurethane dispersions using acid anhydrides give coatings with adjustable hardness, elasticity and resistance.

Patent Document 3 discloses a water-based coating composition for pre-coating steel sheets containing a water-dispersible polyurethane resin using a polyester polyol having an aromatic ring structure in which the content of the aromatic ring structure is in a specific range. , it is described that it forms a coating film with good vegetation resistance, hardness, and substrate hiding properties.
Patent Document 4 describes a urethane resin composition using an aromatic polyester polyol having an aromatic ring concentration in a specific range.

Japanese Patent Application Publication No. 10-120757 Special Publication No. 2010-526921 Japanese Patent Application Publication No. 2011-140561 International Publication 2019/004349

It has been shown that the polyurethane resin compositions using the polyester polyols of Patent Documents 2 to 4 have high adhesion to various resins, but they cannot be used at low temperatures (for example, 80°C) for a short period of time (for example, 10 minutes). In the dried coating film, sufficient adhesion was not obtained.
Furthermore, in applications for materials with anti-fracture properties, conventional aqueous polyurethane resin dispersion compositions require a drying process at 140° C. or higher because they contain a melamine crosslinking agent.

From the perspective of reducing global warming gas emissions, if a coating film can be created by lowering the drying temperature from the conventional 140°C or higher to 20-100°C, it is expected to reduce energy costs and reduce the burden on the environment. Furthermore, in applications for fracture-resistant materials, it is necessary that the created coating film have sufficient adhesion and sufficient hardness.

Therefore, an object of the present invention is to provide an aqueous urethane resin dispersion that can form a coating film by drying at a low temperature of 20 to 100°C. Another object of the present invention is to provide an aqueous urethane resin dispersion that can be used in a composition that forms a coating film having sufficient adhesion, hardness, and flexibility.

The present inventors have discovered that by using a special polyester polyol, it is possible to obtain an aqueous urethane resin dispersion that provides a highly hard coating film by drying at low temperatures and in a short time. It has also been found that, in a preferred embodiment, it is possible to provide an aqueous urethane resin dispersion that can be dried at a low temperature for a short period of time, has a high elastic modulus, has excellent adhesion to a substrate, and provides a coating film with high breaking energy. By enabling low-temperature, short-time processing, it is possible to contribute to achieving Goal 7 of the SDGs (Sustainable Development Goals).

Specifically, the present invention is as follows.
[1] An aqueous polyurethane resin dispersion composition containing a polyurethane resin and an aqueous medium,
The polyurethane resin has a structural unit derived from a polyester polyol (A) whose constituent components are a polyol (Aa) and a dicarboxylic acid (Ab), a structural unit derived from a polyether polyol (G), and a structure derived from a polyisocyanate (B). unit, and has an aromatic ring in the polyurethane resin,
An aqueous polyurethane resin dispersion composition, wherein the content of aromatic rings in the polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass to 10% by mass.
[2] An aqueous polyurethane resin dispersion composition containing two or more types of polyurethane resins and an aqueous medium,
At least one type of polyurethane resin has a structural unit derived from a polyester polyol (A) containing a polyol (Aa) and a dicarboxylic acid (Ab) and a structural unit derived from a polyisocyanate (B), and the polyurethane resin It has an aromatic ring inside,
At least one type of polyurethane resin has a structural unit derived from a polyether polyol (G) and a structural unit derived from a polyisocyanate (B),
An aqueous polyurethane resin dispersion composition in which the content of aromatic rings is 4% by mass to 18% by mass and the content of ether bonds is 0.5% by mass to 10% by mass in the total polyurethane resin.
[3] The aqueous polyurethane resin dispersion according to [1] or [2], wherein the polyurethane resin further has a structural unit derived from the acidic group-containing polyol (C) and a structural unit derived from the chain extender (E). Composition.
[4] The aqueous polyurethane resin dispersion composition according to [1] or [2], wherein the dicarboxylic acid (Ab) contains an aromatic dicarboxylic acid.
[5] The aqueous polyurethane resin dispersion composition according to [1] or [2], which has structural units derived from a polyol (F) other than the polyester polyol (A), the acidic group-containing polyol, and the polyether polyol (G). thing.
[6] The aqueous polyurethane resin dispersion composition according to [4], wherein the two carboxyl groups in the aromatic dicarboxylic acid are in a para-position relationship on a benzene ring.
[7] The aqueous polyurethane resin dispersion composition according to [5], wherein the polyol (F) is a polycarbonate polyol.
[8] The aqueous polyurethane resin dispersion composition according to [4], wherein the polyether polyol (G) and the polyol (F) have 2 hydroxyl groups.
[9] The aqueous polyurethane resin dispersion composition according to [3], wherein the chain extender (E) is a polyamine.
[10] The aqueous polyurethane resin dispersion composition according to [1], wherein the mass ratio of the polyester polyol (A) and the polyether polyol (G) is 50:50 to 90:10.
[11] The aqueous polyurethane resin dispersion composition according to [1] or [2], which contains 50 to 100% by mass of an alicyclic polyisocyanate based on the total amount of the polyisocyanate (B).
[12] The aqueous polyurethane resin dispersion composition according to [1] or [2], wherein the polyurethane resin has a weight average molecular weight of 100,000 or more.
[13] The aqueous polyurethane resin dispersion composition according to [1] or [2], wherein the dicarboxylic acid (Ab) has a hydroxyl value of 55 to 140 mgKOH/g.
[14] A coating material composition comprising the aqueous polyurethane resin dispersion composition according to [1] or [2].
[15] A coating film obtained by applying and drying the coating material composition according to [14].
[16] When the coating film obtained by drying the coating material composition at 80° C. for 45 minutes was subjected to a checkerboard peel test on the electrodeposited surface, no peeling was observed. 15].
[17] A method for producing a coating film, comprising the step of drying the coating material composition according to [14] at 20°C to 100°C.
[18] The coating material composition according to [14] for use in a metal exterior primer or base coat.
[19] The coating material composition according to [14] for use in fracture-resistant materials.
[20] The coating material composition according to [15] for use in the coating film according to [15], a floor coat, a plastic or rubber coat.
[21] A steel plate treatment agent containing the coating material composition according to [14].
[22] Constituent units derived from polyester polyol (A) containing polyol (Aa) and dicarboxylic acid (Ab), constituent units derived from polyether polyol (G), and constituent units derived from polyisocyanate (B). and has an aromatic ring in the polyurethane resin, the content of the aromatic ring in the polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass to 10% by mass. %, polyurethane resin.
[23] A coating film containing the polyurethane resin described in [22].
[24] A polyurethane resin composition containing two or more types of polyurethane resins,
At least one type of polyurethane resin has a structural unit derived from a polyester polyol (A) containing a polyol (Aa) and a dicarboxylic acid (Ab) and a structural unit derived from a polyisocyanate (B), and the polyurethane resin It has an aromatic ring inside,
At least one type of polyurethane resin has a structural unit derived from a polyether polyol (G) and a structural unit derived from a polyisocyanate (B),
A polyurethane resin composition in which the content of aromatic rings is 4% by mass to 18% by mass and the content of ether bonds is 0.5% by mass to 10% by mass in the total polyurethane resin.
[25] A coating film containing the polyurethane resin composition according to [24].

A composition containing the aqueous urethane resin dispersion of the present invention can form a coating film when dried at a low temperature of 20 to 100°C. Further, the composition containing the aqueous urethane resin dispersion of the present invention forms a coating film having sufficient adhesion, hardness, and flexibility.

[First aspect of the present invention]
The present invention is an aqueous polyurethane resin dispersion composition comprising a polyurethane resin and an aqueous medium,
The polyurethane resin has a structural unit derived from a polyester polyol (A) whose constituent components are a polyol (Aa) and a dicarboxylic acid (Ab), a structural unit derived from a polyether polyol (G), and a structure derived from a polyisocyanate (B). unit, and has an aromatic ring in the polyurethane resin,
An aqueous polyurethane resin dispersion composition, wherein the content of aromatic rings in the polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass to 10% by mass.

The polyurethane resin further contains a structural unit derived from the acidic group-containing polyol (C), a structural unit derived from the chain extender (E), and a polyol (F) other than the component (A), component (G), and component (C). It is preferable to have a structural unit derived from
Further, in the aqueous polyurethane resin dispersion, it is preferable that the polyurethane resin is neutralized with a neutralizing agent (D).

That is, in the polyurethane resin, the polyol (X) as a component that reacts with the polyisocyanate (B) to form the polyurethane resin includes a polyester polyol (A), a polyether polyol (G), and optionally an acidic group-containing polyol ( C) and optionally a polyol (F). On the other hand, the polyol (Aa) that reacts with the dicarboxylic acid (Ab) to form the polyester polyol (A) includes an optionally branched polyol (Aa1) and an optionally linear polyol (Aa2). Further, dicarboxylic acids (Ab) optionally include aromatic dicarboxylic acids (Ab1) and optionally aliphatic dicarboxylic acids (Ab2).

In this specification, "substantially 100% by mass" refers to other substances that may change the properties of the aqueous polyurethane resin dispersion composition or the functions and properties of the coating film obtained from the aqueous polyurethane resin dispersion composition. This means that the ingredients are not included, but does not exclude that they may be included to the extent that their functions and characteristics are not impaired.

<Polyester polyol (A)>
Polyester polyol (A) is a polyol formed by reacting polyol (Aa) and dicarboxylic acid (Ab).
Polyester polyol (A) is obtained by a method similar to a known polyester production method in which polyol (Aa) and dicarboxylic acid (Ab) are subjected to dehydration condensation.

The polyester polyol (A) is preferably 40% by mass or more, and preferably 50% by mass or more of the total polyol (X) constituting the polyurethane resin, from the viewpoint of obtaining a highly hard coating film by drying at a low temperature and in a short time. It is more preferably 60% by mass or more, even more preferably 80% by mass or more. Within this range, a coating film with a high elastic modulus can be obtained by drying at a low temperature for a short time. In addition, from the viewpoint of obtaining a highly adhesive coating film by drying at low temperature and in a short time, the polyester polyol (A) is preferably 90% by mass or less, and 80% by mass or less of the total polyol (X) constituting the polyurethane resin. More preferred.

It is preferable that the number of hydroxyl groups in the polyester polyol (A) is 2. That is, polyester diol is preferred. This is because the aqueous polyurethane resin dispersion composition can form a coating film with excellent hardness and adhesion without crosslinking, so crosslinking is not necessarily necessary.

The acid value of the polyester polyol (A) is preferably 0.01 to 5.0 mgKOH/g. Within this range, a polyurethane resin with particularly good physical properties can be obtained using this as a raw material. The acid value is more preferably 0.01 to 1.0 mgKOH/g, even more preferably 0.01 to 0.5 mgKOH/g. By setting it as this range, the hardness of the coating film obtained by drying an aqueous urethane resin dispersion and the adhesiveness to an electrodeposition coating surface can be improved.
In this specification, the acid value is a value measured according to the indicator titration method of JIS K 1557.

The hydroxyl value of the polyester polyol (A) is preferably 22.5 to 280 mgKOH/g, more preferably 35 to 225 mgKOH/g, even more preferably 55 to 140 mgKOH/g, and even more preferably 55 to 125 mgKOH/g. /g is particularly preferred. Within this range, the hardness of the coating film obtained by drying the aqueous urethane resin dispersion and the adhesion to the electrodeposited surface can be improved.
In this specification, the hydroxyl value is a value measured according to method B of JIS K 1557.

The number average molecular weight Mn of the polyester polyol (A) is preferably 400 to 5,000. Within this range, fluidity (for example, viscosity of 500 to 10,000 cP) can be easily obtained under heating (for example, 75° C.), resulting in excellent handling properties. The number average molecular weight Mn is more preferably 500 to 3,000, still more preferably 800 to 2,000, particularly preferably 900 to 2,000. In this specification, the number average molecular weight Mn is the number average molecular weight calculated based on the hydroxyl value measured in accordance with JIS K 1577. Specifically, the hydroxyl value is measured and calculated using the terminal group quantitative method using (56.1 x 1000 x valence)/hydroxyl value (in this formula, the unit of hydroxyl value is [mgKOH/g] ). In the above formula, the valence is the number of hydroxyl groups in one molecule.

The weight average molecular weight Mw of the polyester polyol (A) is preferably 500 to 30,000, more preferably 1,000 to 13,000. In this specification, the weight average molecular weight Mw is a value measured by GPC.

The degree of dispersion Mw/Mn of the polyester polyol (A) is preferably 1.0 to 3.0, more preferably 1.6 to 2.5.

<Polyol (Aa)>
The polyol (Aa) used in the present invention reacts with a dicarboxylic acid (Ab) described below to form a polyester polyol (A).

The polyol (Aa) may contain only a branched polyol (Aa1), or may contain a branched polyol (Aa1) and a linear polyol (Aa2).

The branched polyol (Aa1) is a polyol having a tertiary carbon atom or a quaternary carbon atom in one molecule, such as 1,2-propylene glycol, 1-methyl-1,3-butylene. Glycol, 2-methyl-1,3-butylene glycol, neopentyl glycol, 1-methyl-1,4-pentanediol, 2-methyl-1,4-pentanediol, 3-methyl-1,4-pentanediol, 1-Methyl-1,5-pentanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2-dimethylbutylene glycol, 1,3-dimethylbutylene glycol, 2 , 3-dimethylbutylene glycol, 1,4-dimethylbutylene glycol, etc. Among these, from the viewpoint of improving the elastic modulus and adhesion of the resulting coating film, diols having a quaternary carbon atom are preferred. is preferable, and neopentyl glycol is more preferable. Further, the polyol having a branched chain preferably has 4 to 8 carbon atoms, and the branched chain represents a hydrocarbon group, preferably an alkyl group having 1 to 4 carbon atoms, and the branched chain has 1 to 2 carbon atoms. More preferably, it is an alkyl group.
These branched polyols (Aa1) can be used alone or in combination of two or more.

The content of the branched polyol (Aa1) is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass, and especially Preferably it is substantially 100% by mass.

As the linear polyol (Aa2), ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol , dipropylene glycol, tripropylene glycol, and the like can be used, with 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol being preferred. The content of the linear polyol (Aa2) is preferably 20% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, particularly preferably substantially It is 0% by mass.
These linear polyols (Aa2) can be used alone or in combination of two or more.

<Dicarboxylic acid (Ab)>
The polyol (Aa) used in the present invention reacts with a dicarboxylic acid (Ab) to form a polyester polyol (A).

The dicarboxylic acid (Ab) preferably contains an aromatic dicarboxylic acid (Ab1), and the content thereof is preferably 80% by mass or more, more preferably 90% by mass based on the total amount of the dicarboxylic acid (Ab). % or more, more preferably 95% by mass, particularly preferably substantially 100% by mass.

Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, biphenyldicarboxylic acid, and tetrahydrophthalic acid. , or their reactive derivatives such as acid anhydrides, alkyl esters, and acid halides, and phthalic acid, isophthalic acid, and terephthalic acid are preferable. It may have an alkyl group having 1 to 4 carbon atoms and/or an alkoxy group having 1 to 4 carbon atoms. These aromatic dicarboxylic acids can be used alone or in combination of two or more. Among these, the aromatic dicarboxylic acid is preferably such that the two carboxyl groups in the aromatic dicarboxylic acid are in a para-position relationship on the benzene ring from the viewpoint of increasing the elastic modulus and hardness of the resulting coating film, and terephthalate is preferable. Acids are more preferred.

The dicarboxylic acid (Ab) may contain an aliphatic dicarboxylic acid (Ab2) in addition to the aromatic dicarboxylic acid (Ab1). Aliphatic dicarboxylic acids include, but are not limited to, malonic acid, succinic acid, tartaric acid, oxalic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, alkylsuccinic acid, linoleic acid, and maleic acid. , fumaric acid, mesaconic acid, citraconic acid, itaconic acid, etc., or reactive derivatives thereof such as acid anhydrides, alkyl esters, and acid halides. These aliphatic dicarboxylic acids can be used alone or in combination of two or more. The content of aliphatic dicarboxylic acid is 20% by mass or less in the total amount of dicarboxylic acid (Ab), preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably substantially 0% by mass or less. Mass%.

<Polyether polyol (G)>
The polyether polyol (G) is preferably contained in an amount of less than 70% by mass, more preferably contained in an amount of less than 60% by mass, based on the total polyol (X) constituting the polyurethane resin. , more preferably in an amount of 10 to 50% by weight, and particularly preferably in an amount of 10 to 40% by weight. This range is preferable because a highly hard coating film can be obtained by drying at a low temperature and in a short time. Further, the concentration of ether bonds in the polyurethane resin can be adjusted as appropriate so that it becomes the above concentration.

It is preferable that the number of hydroxyl groups in the polyether polyol (G) is 2. That is, diol is preferred. This is because the aqueous polyurethane resin dispersion composition can form a coating film with excellent hardness and adhesion without crosslinking, so crosslinking is not necessarily necessary.

The number average molecular weight of the polyether polyol (G) is preferably from 500 to 10,000, more preferably from 650 to 5,000, even more preferably from 900 to 3,000.

The hydroxyl value of the polyether polyol (G) is preferably from 11 to 225, more preferably from 22 to 173, even more preferably from 37 to 125.

Examples of the polyether polyol (G) include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, random copolymers and block copolymers of ethylene oxide and propylene oxide, and ethylene oxide and butylene oxide.
The polyether polyol (G) may be used alone or in combination.

The mass ratio of polyester polyol (A) to polyether polyol (G) is preferably 50:50 to 90:10, more preferably 55:45 to 80:20, and 60:40 to 70. :30 is more preferable. It is preferable that the mass ratio is within the above range because the coating film can exhibit adhesiveness to the base material while having a high elastic modulus.

<Polyol (F) other than component (A), component (G) and component (C)>
The polyurethane resin contains a polyester polyol (A), a polyether polyol (G), and an acidic group described below in a polyol (X) as a component that can be reacted with a polyisocyanate (B) described below to form a polyurethane resin. In addition to the contained polyol (C), a polyol (F) may be contained.
Such polyol (F) is preferably contained in an amount of less than 50% by mass, and may not be contained in an amount of less than 40% by mass in all polyols (X) constituting the polyurethane resin. More preferably, it is contained in an amount of 5 to 30% by weight, even more preferably in an amount of 5 to 20% by weight. As long as the effects of the present invention are not impaired, both the type and amount of polyol (F) can be adjusted as appropriate by those skilled in the art. Other polyols (F) may not be included in the polyol.

As the polyol (F), known ones can be used. For example, high molecular weight polyols such as polycarbonate polyols; ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, Short products such as neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 3-methyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, etc. Chain aliphatic diols; cycloaliphatic diols such as 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and hydrogenated bisphenol A; diols such as bisphenol A, hydroquinone, bishydroxyethoxybenzene, and their alkylene oxide adducts; etc. Polyol (F) can be used alone or in combination of two or more. Among these, from the viewpoint of substrate adhesion and breaking energy, high molecular weight polyols are preferred, and polycarbonate polyols are more preferred.
As the above polyol (F), a commercially available one may be used, or one prepared individually may be used.

It is preferable that the number of hydroxyl groups in the polyol (F) is 2. That is, diol is preferred. This is because the aqueous polyurethane resin dispersion composition can form a coating film with excellent hardness and adhesion without crosslinking, so crosslinking is not necessarily necessary. From the viewpoint of adhesion, it is preferable not to have crosslinking.

The number average molecular weight of the high molecular weight polyol is preferably from 500 to 10,000, more preferably from 650 to 5,000, even more preferably from 900 to 3,000.

The hydroxyl value of the high molecular weight polyol is preferably from 10 to 225, more preferably from 22 to 175, even more preferably from 37 to 125.

The polycarbonate polyol used as the polyol (F) is obtained by reacting one or more polyol components with a carbonate ester or phosgene. A polycarbonate polyol obtained by reacting one or more polyol monomers with a carbonate ester is preferred because it is easy to manufacture from the viewpoint of safety and handling of reagents, and there is no by-product of terminally chlorinated products.

As the polyol component of the polycarbonate polyol, known ones can be used. For example, linear aliphatic diols such as 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol, 2-methyl-1,5- Aliphatic polyols such as branched aliphatic diols such as pentanediol; diols having an alicyclic structure in the main chain such as 1,4-cyclohexanedimethanol; 1,4-benzenedimethanol, 1,3-benzene Examples include dimethanol, polyester polyol, polyether polyol. The polyol component of the polycarbonate polyol may be used alone or in combination.

The polycarbonate polyol may contain ether bonds or ester bonds in its molecule in a number less than the average number of carbonate bonds in one molecule, as long as the properties of the polycarbonate polyol are not impaired.

<Polyisocyanate (B)>
As the polyisocyanate (B), known ones can be used. For example, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 2,4- Diphenylmethane diisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5 - Aromatic polyisocyanates such as naphthylene diisocyanate, 4,4',4''-triphenylmethane triisocyanate, m-isocyanatophenylsulfonyl isocyanate, p-isocyanatophenylsulfonyl isocyanate; ethylene diisocyanate, tetramethylene diisocyanate, penta Methylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl capro Aliphatic polyisocyanates such as ester, bis(2-isocyanatoethyl) fumarate, bis(2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate; isophorone diisocyanate (IPDI) , 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis(2-isocyanatoethyl)-4-diclohexene-1,2-dicarboxylate, Examples include alicyclic polyisocyanates such as 2,5-norbornane diisocyanate and 2,6-norbornane diisocyanate. Part or all of the structure of the polyisocyanate (B) may be derivatized such as isocyanurate, carbodiimide, or biuret. Polyisocyanate (B) may be used alone or in combination.

Among the above polyisocyanates (B), alicyclic polyisocyanates are preferred from the viewpoint of adhesion to the substrate, and from the viewpoints of hardness and breaking energy, isophorone diisocyanate (IPDI) and/or 4,4'-dicyclohexylmethane diisocyanate. (Hydrogenated MDI) is more preferred, and 4,4'-dicyclohexylmethane diisocyanate is even more preferred. In the polyisocyanate (B), the alicyclic polyisocyanate is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and even more preferably 90 to 100% by mass.

Polyisocyanate (B) may be used alone or in combination.
It is preferable that the polyisocyanate (B) does not contain blocked isocyanate. This is because when an aqueous polyurethane resin dispersion composition is used as a coating film, it is cured at a low temperature, so blocked isocyanates that activate the isocyanate by removing blocks at high temperatures are not suitable.

The amount of polyisocyanate (B) used is based on the isocyanate group of polyisocyanate (Ab), all polyols (polyester polyol (A), polyether polyol (G), any polyol (F), and any acidic group-containing The ratio (isocyanate group/hydroxyl group (molar ratio)) of the total amount of polyol (C) to the hydroxyl group is preferably 1.5 to 2.5, particularly 1.6 to 2.1. preferable.

<Acidic group-containing polyol (C)>
The acidic group-containing polyol (C) contains two or more hydroxyl groups and one or more acidic groups in one molecule. The acidic group-containing polyol (C) may be used alone or in combination.

As the acidic group-containing polyol (C), known ones can be used. For example, dimethylolalkanoic acids such as 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid; N,N-bishydroxyethylglycine, N,N-bishydroxyethylalanine, 3,4-dihydroxybutane Examples include sulfonic acid, 3,6-dihydroxy-2-toluenesulfonic acid, and the like. Among them, from the viewpoint of easy availability, dimethylol alkanoic acid having 4 to 12 carbon atoms and containing two methylol groups is preferred, and among dimethylol alkanoic acids, 2,2-dimethylol propionic acid is more preferred.

From the viewpoint of resin dispersibility, the acidic group-containing polyol (C) is preferably contained in an amount of 4 to 20% by mass, and 8 to 18% by mass, based on the total polyol (X) constituting the polyurethane resin. It is more preferably contained in an amount of 10 to 16% by weight, and particularly preferably 12 to 15% by weight.

In the aqueous polyurethane resin dispersion composition, the total number of hydroxyl equivalents of the polyester polyol (A), polyether polyol (G), acidic group-containing polyol (C), and polyol (F) is 50 to 4000. is preferred. When the number of hydroxyl equivalents is within this range, it is easy to produce an aqueous polyurethane resin dispersion composition containing the obtained polyurethane resin. From the viewpoint of the breaking energy of the coating film obtained from the resulting aqueous polyurethane resin dispersion composition, the number of hydroxyl equivalents is preferably 100 to 2,500, more preferably 120 to 1,500, particularly preferably 150 to 1,000.

The number of hydroxyl group equivalents can be calculated using the following formulas (1) and (2).
Number of hydroxyl equivalents of each polyol component = Molecular weight of each polyol component / Number of hydroxyl groups of each polyol component... (1)
Total number of hydroxyl equivalents of polyol components = M/total number of moles of polyol components...(2)
In formula (2), M is [number of hydroxyl equivalents of polyester polyol (A) x number of moles of polyester polyol (A)] + [number of hydroxyl equivalents of polyether polyol (G) x number of moles of polyether polyol (G)] [number of moles] + [number of hydroxyl equivalents of acidic group-containing polyol (C) x number of moles of acidic group-containing polyol (C)] + [number of hydroxyl equivalents of polyol (F) x number of moles of polyol (F)]] .

<Neutralizing agent (D)>
One type of neutralizing agent (D) may be used alone, or a plurality of types may be used in combination.

As the neutralizing agent (D), known ones can be used. For example, non-volatile bases such as sodium hydroxide and potassium hydroxide; tertiary amines such as trimethylamine, triethylamine, dimethylethanolamine, methyldiethanolamine, and triethanolamine; secondary amines such as dimethylamine, diethylamine, and dibutylamine; ethylenediamine, Primary amines such as methylamine, ethylamine, butylamine; ammonia, etc. can be used.

The neutralizing agent (D) volatilizes and disappears from the polyurethane film at the temperature (usually 50 to 180°C) when drying the aqueous medium in the coating material composition, resulting in even higher hardness. Therefore, the boiling point is preferably 200°C or less, more preferably in the range of -50 to 180°C. When drying a coating film in a short period of several seconds to one hour at a low temperature of 100°C or lower, the boiling point is preferably 130°C or lower, more preferably 110°C or lower.

When using the neutralizing agent (D), the amount used is 0.8 to 1.2 based on the number of moles of acidic groups in the acidic group-containing polyol (C) contained in the aqueous polyurethane resin dispersion composition. Preferably, the range is twice that. When the amount of the neutralizing agent (D) used is 0.8 times or more the number of moles of the acidic group contained in the aqueous polyurethane resin dispersion composition, the stability of the resulting dispersion is high; If it is 1.2 times or less, a coating film with high hardness, substrate adhesion, and breaking energy can be obtained in a short period of several seconds to 10 minutes under low-temperature drying at 100° C. or lower.

<Chain extender (E)>
The chain extender (E) is a compound that is reactive with the isocyanate groups of the polyurethane prepolymer. One type of chain extender (E) may be used alone, or a plurality of types may be used in combination.
In this specification, polyols that also function as chain extenders are not included in chain extenders (E) but are included in polyols (X).

As the chain extender (E), known ones can be used. For example, ethylenediamine, 1,4-tetramethylenediamine, 2-methyl-1,5-pentanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, 1,4-hexamethylenediamine, 3-aminomethyl -Amines such as 3,5,5-trimethylcyclohexylamine, 1,3-bis(aminomethyl)cyclohexane, xylylenediamine, piperazine, 2,5-dimethylpiperazine, and aminoethylethanolamine; is preferred.

Among the chain extenders (E), diamines having a number average molecular weight (Mn) of 300 or less are preferred. A Mn of 300 or less is necessary to increase the cohesive force of the polyurethane resin, and the use of diamine not only increases the Mn of the polyurethane resin and improves its durability, but also reduces the breaking energy. It is also preferable from the viewpoint of

It is preferable that the amount of the chain extender (E) added is equal to or less than the equivalent of the isocyanato group that serves as a chain extension starting point in the resulting urethane polymer. If the chain extender (E) is added in an amount exceeding the equivalent of the isocyanate group, the molecular weight of the chain-extended urethane polymer may decrease, resulting in a decrease in cohesive force, which may result in a decrease in rupture energy. .

Moreover, as the chain extender (E), in addition to the above-mentioned examples, a compound having three or more functional groups reactive with an isocyanato group may be used in combination. By using such a compound in combination, it becomes easier to control the content of N(C=O)NH groups. As a result, it becomes easier to control the drying rate when forming a coating film. Examples of such compounds include polyamines having a total of three or more amino groups and/or imino groups in one molecule, and compounds such as diethylenetriamine can be used.

<<Polyurethane resin>>
<Aromatic ring>
The polyurethane resin has an aromatic ring, and the content of the aromatic ring in the polyurethane resin is 4% by mass to 18% by mass, preferably 5 to 16% by mass, and 7 to 14% by mass. It is more preferable.
By setting it as this range, the elastic modulus of the coating film of polyurethane resin can be made high.
The ratio of aromatic rings in a polyurethane resin indicates the content of aromatic rings relative to the total amount of constituent components of the polyurethane resin. For example, a polyurethane resin has constituent components derived from a polyester polyol (A), a polyisocyanate (B), an acidic group-containing polyol (C), a chain extender (E), a polyol (F), and a polyether polyol (G), respectively. In this case, the content of aromatic rings in the raw materials is shown relative to the total mass of these raw materials used for production. As the molecular weight of the aromatic ring, the molecular weight of a benzene ring or a naphthalene ring excluding organic groups is used. For example, the proportion of aromatic rings in a polyurethane resin made of a raw material containing a benzene ring structure without an organic group can be determined from the following formula (1).
Formula (1): Content of aromatic ring structure (mass%) = 100 x (atomic weight of carbon x 6 + atomic weight of hydrogen x 4) x {(number of moles [mol] of polyester polyol (A)) x (polyester polyol (Number of aromatic rings contained in (A)) + (Number of moles [mol] of polyisocyanate (B)) × (Number of aromatic rings contained in polyisocyanate (B)) + (Acidic group-containing polyol (C ) x (number of aromatic rings contained in acidic group-containing polyol (C)) + (number of moles [mol] of chain extender (E)) x (number of moles [mol] of chain extender (E)) Number of aromatic rings included) + (Number of moles of polyol (F) [mol]) x (Number of aromatic rings included in polyol (F)) + (Number of moles of polyether polyol (G) [mol] ) x (number of aromatic rings contained in polyether polyol (G))}/(mass of polyurethane resin [g])
At least one selected from the group consisting of structural units derived from polyester polyol (A), structural units derived from polyether polyol (G), and structural units derived from polyisocyanate (B) has an aromatic ring. Furthermore, the structural unit derived from any acidic group-containing polyol (C), the structural unit derived from any chain extender (E), and the structural unit derived from any polyol (F) have an aromatic ring. Good too.

<ether bond>
The polyurethane resin has an ether bond, and the content of the ether bond in the polyurethane resin is 0.5% to 10% by mass, preferably 0.8% to 8% by mass, and 1.5% to 6% by mass. It is more preferably 2% by mass, and even more preferably 2 to 5% by mass.
By setting it as this range, the adhesiveness of the coating film of polyurethane resin can be improved.
The ratio of ether groups in a polyurethane resin indicates the content of ether groups based on the total amount of constituent components of the polyurethane resin. For example, a polyurethane resin has constituent components derived from a polyester polyol (A), a polyisocyanate (B), an acidic group-containing polyol (C), a chain extender (E), a polyol (F), and a polyether polyol (G), respectively. In this case, the content of ether groups in the raw materials is shown relative to the total mass of these raw materials used for production.
The proportion of ether bonds in the polyurethane resin can be determined from the following formula (2).
Formula (2): Content of ether bond (mass%) = 100 x (atomic weight of oxygen x 1) x {(number of moles [mol] of polyester polyol (A)) x (ether contained in polyester polyol (A)) Number of bonds) + (Number of moles of polyisocyanate (B) [mol]) × (Number of ether bonds contained in polyisocyanate (B)) + (Number of moles of acidic group-containing polyol (C) [mol]) × (Number of ether bonds contained in acidic group-containing polyol (C)) + (Number of moles [mol] of chain extender (E)) x (Number of ether bonds contained in chain extender (E)) + (Polyol (Number of moles [mol] of (F)) × (Number of ether bonds contained in polyol (F)) + (Number of moles [mol] of polyether polyol (G)) × (Number of moles contained in polyether polyol (G) number of ether bonds)}/(mass [g] of polyurethane resin).
The structural unit derived from polyether polyol (G) has an ether bond. In addition, structural units derived from polyester polyol (A), structural units derived from polyisocyanate (B), structural units derived from any acidic group-containing polyol (C), structural units derived from any chain extender (E), and optional The structural unit derived from the polyol (F) may have an ether bond.

The polyurethane resin in the aqueous polyurethane resin dispersion composition of the present invention preferably has the following characteristics.
The number average molecular weight (Mn) of the polyurethane resin is preferably 50,000 or more, more preferably 100,000 or more from the viewpoint of breaking energy of a low-temperature dried coating film. By setting the number average molecular weight to 50,000 or more, the coating film obtained by drying the composition at a temperature of 100° C. or lower exhibits better breaking energy. The upper limit is not particularly limited as long as it can be synthesized and has a viscosity that allows it to be handled as an aqueous dispersion. The upper limit of the number average molecular weight is usually 2,000,000 or less, preferably 1,000,000 or less.

The weight average molecular weight (Mw) of the polyurethane resin is preferably 100,000 or more, more preferably 400,000 or more. It is preferable that the weight average molecular weight is within the above range from the viewpoint of the breaking energy of the coating film.

The acid value of the polyurethane resin is not particularly limited, but is preferably 18 to 40 mgKOH/g, more preferably 20 to 35 mgKOH/g, based on solid content. When the acid value of the polyurethane resin is greater than 40 mgKOH/g based on solid content, the dispersibility in an aqueous medium tends to deteriorate. When the acid value is less than 18 mgKOH/g based on solid content, the adhesion to the substrate tends to decrease. The acid value can be measured according to the indicator titration method of JIS K 1557. In the measurement, the neutralizing agent used to neutralize the acidic groups is removed. For example, when organic amines are used as a neutralizing agent, a coating film obtained by applying an aqueous polyurethane resin dispersion composition onto a glass plate and drying it at a temperature of 60°C and under a reduced pressure of 20 mmHg for 24 hours is obtained. can be dissolved in N-methylpyrrolidone (NMP) and the acid value can be measured according to the indicator titration method of JIS K 1557.

<Aqueous polyurethane resin dispersion composition>
The aqueous polyurethane resin dispersion composition includes the polyurethane resin and an aqueous medium, and the polyurethane resin is dispersed in the aqueous medium.
Examples of the aqueous medium include water such as clean water, ion-exchanged water, distilled water, and ultrapure water, and a mixed medium of water and a hydrophilic organic solvent.
Examples of hydrophilic organic solvents include ketones such as acetone and ethyl methyl ketone; pyrrolidones such as N-methylpyrrolidone and N-ethylpyrrolidone; ethers such as diethyl ether and dipropylene glycol dimethyl ether; methanol, ethanol, n -Alcohols such as propanol, isopropanol, ethylene glycol, diethylene glycol; Amides such as β-alkoxypropionamide represented by "KJCMPA(R)-100" manufactured by KJ Chemical; 2-(dimethylamino)-2-methyl Examples include hydroxyl group-containing tertiary amines such as -1-propanol (DMAP).

The amount of the hydrophilic organic solvent in the aqueous medium is preferably 0 to 20% by weight, more preferably 0 to 15% by weight, and even more preferably 0 to 10% by weight.

The pH of the aqueous polyurethane resin dispersion composition is preferably 5.0 to 10.0, more preferably 6.0 to 9.5, and even more preferably 6.5 to 9.0. preferable.

The proportion of polyurethane resin in the aqueous dispersion is preferably 5 to 60% by weight, more preferably 20 to 50% by weight.

<Method for producing aqueous polyurethane resin dispersion composition>
An aqueous polyurethane resin dispersion composition can be produced by a known method described in International Publication No. 2016/039396 and the like. For example, the following manufacturing method may be mentioned.
The first manufacturing method is a method of obtaining an aqueous polyurethane resin dispersion composition by mixing all raw materials, reacting them, and dispersing them in an aqueous medium.
The second production method involves reacting all polyol components with polyisocyanate to produce a prepolymer, neutralizing the acidic groups of the prepolymer, dispersing it in an aqueous medium, and reacting with a chain extender. This is a method for obtaining an aqueous polyurethane resin dispersion composition.
As a method for manufacturing the aqueous polyurethane resin dispersion composition, the second manufacturing method described above is preferred because the molecular weight can be easily controlled.

In particular, in the present invention, the aqueous polyurethane resin dispersion composition can be produced by a method including the following (I) to (IV) and optionally (V).
(I) Polyester polyol (A), polyether polyol (G), polyisocyanate (B), any acidic group-containing polyol (C), and any polyol (F) in the presence or absence of an organic solvent. A step of reacting with to obtain a polyurethane prepolymer,
(II) neutralizing the acidic groups of the polyurethane prepolymer with a neutralizing agent (D);
(III) dispersing the polyurethane prepolymer in an aqueous medium;
(IV) a step of increasing the molecular weight of the polyurethane prepolymer with a chain extender (E), and optionally,
(V) Step of removing organic solvent.

[Second aspect of the present invention]
A second aspect of the present invention is an aqueous polyurethane resin dispersion composition comprising two or more types of polyurethane resins and an aqueous medium,
At least one type of polyurethane resin (I) has a structural unit derived from a polyester polyol (A) whose constituent components are a polyol (Aa) and a dicarboxylic acid (Ab) and a structural unit derived from a polyisocyanate (B), and has an aromatic ring in the polyurethane resin,
At least one type of polyurethane resin (II) has a structural unit derived from a polyether polyol (G) and a structural unit derived from a polyisocyanate (B),
An aqueous polyurethane resin dispersion composition in which the content of aromatic rings is 4% by mass to 18% by mass and the content of ether bonds is 0.5% by mass to 10% by mass in the total polyurethane resin. .

Both polyurethane resins (I) and (II) further contain structural units derived from acidic group-containing polyol (C), structural units derived from chain extender (E), component (A), component (G), and ( It is preferable to have a structural unit derived from polyol (F) other than component C).

The polyol (Aa) and dicarboxylic acid (Ab) which are constituent components of the polyester polyol (A) in the polyurethane resin (I) include those similar to those in the first aspect of the present invention.
As the polyester polyol (A) in the polyurethane resin (I), the same ones as in the first aspect of the present invention can be mentioned.
The content of the polyester polyol (A) in the polyurethane resin (I) is such that the content of aromatic rings in the total polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass. It is adjusted appropriately so that it becomes 10% by mass.

As the polyisocyanate (B) in the polyurethane resin (I), the same ones as in the first aspect of the present invention can be mentioned.
The amount of polyisocyanate (B) used in polyurethane resin (I) is such that the ratio of isocyanate groups of polyisocyanate (Ab) to hydroxyl groups of all polyols (Y) (isocyanate group/hydroxyl group (molar ratio)) is 1.7. ˜2.5 is preferable, and 1.75˜2.3 is particularly preferable. Note that the total polyol (Y) refers to all polyols constituting the polyurethane resin (I).

Examples of the acidic group-containing polyol (C), neutralizing agent (D), chain extender (E), and polyol (F) in the polyurethane resin (I) include the same ones as in the first aspect of the present invention.
The acidic group-containing polyol (C) in the polyurethane resin (I) is preferably 4 to 20% by mass, more preferably 8 to 18% by mass, and more preferably 10 to 16% by mass, based on the total polyol (Y) constituting the polyurethane resin (I). % by weight is more preferable, and 12 to 15% by weight is particularly preferable. Within this range, a stable aqueous dispersion can be obtained.

The polyol (F) in the polyurethane resin (I) has an aromatic ring content of 4% to 18% by mass and an ether bond content of 0.5% to 10% by mass in the total polyurethane resin. Adjustments will be made as appropriate to ensure that. Further, the content of the two or more types of polyurethane resins relative to the total amount is also adjusted to be within the same range as in the first embodiment.

Polyurethane resin (I) has an aromatic ring. In the polyurethane resin (I), at least one selected from the group consisting of structural units derived from the polyester polyol (A) and structural units derived from the polyisocyanate (B) has an aromatic ring. Furthermore, the structural unit derived from any acidic group-containing polyol (C), the structural unit derived from any chain extender (E), and the structural unit derived from any polyol (F) have an aromatic ring. Good too. It is preferable that the polyurethane resin (I) does not have an ether bond.

Examples of the polyether polyol (G) in the polyurethane resin (II) include those similar to those in the first embodiment of the present invention.
The content of the polyether polyol (G) in the polyurethane resin (I) is such that the content of aromatic rings in the total polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass. It is adjusted as appropriate so that the amount is 10% by mass.

As the polyisocyanate (B) in the polyurethane resin (II), the same ones as in the first aspect of the present invention can be mentioned.
The amount of polyisocyanate (B) used in polyurethane resin (II) is such that the ratio of isocyanate groups of polyisocyanate (Ab) to hydroxyl groups of all polyols (Z) (isocyanate group/hydroxyl group (molar ratio)) is 1.7. ˜2.5 is preferable, and 1.75˜2.3 is particularly preferable.

As the acidic group-containing polyol (C), neutralizing agent (D), chain extender (E) and polyol (F) in the polyurethane resin (II), the same ones as in the first aspect of the present invention can be mentioned.
The acidic group-containing polyol (C) in the polyurethane resin (II) is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, and more preferably 2 to 8% by mass, based on the total polyol (Z) constituting the polyurethane resin (II). Mass % is more preferred. Within this range, a coating film with high drying properties can be obtained.

The polyol (F) in the polyurethane resin (II) has an aromatic ring content of 4% to 18% by mass and an ether bond content of 0.5% to 10% by mass. Adjust accordingly.

Polyurethane resin (II) has an ether bond. The structural unit derived from polyether polyol (G) has an ether bond. The structural units derived from the polyisocyanate (B), the structural units derived from any acidic group-containing polyol (C), the structural units derived from any chain extender (E), and the structural units derived from any polyol (F), It may have an ether bond. It is preferable that the polyurethane resin (II) does not have an aromatic ring.

An aqueous polyurethane resin dispersion composition containing two or more polyurethane resins including polyurethane resin (I) and polyurethane resin (II) and an aqueous medium has an aromatic ring content of 4% by mass or more in the total polyurethane resin. The amount is 18% by weight, preferably 5 to 16% by weight, and more preferably 7 to 14% by weight. By setting it as this range, the elastic modulus of the coating film of polyurethane resin can be made high.

An aqueous polyurethane resin dispersion composition containing two or more types of polyurethane resins including polyurethane resin (I) and polyurethane resin (II) and an aqueous medium has an ether bond content of 0.5% by mass in the total polyurethane resin. ~10% by weight, preferably from 0.8 to 8% by weight, more preferably from 1.5 to 6% by weight, even more preferably from 2 to 5% by weight. By setting it as this range, the adhesiveness of the coating film of polyurethane resin can be improved.
The aqueous medium, polyurethane resin content, and pH of the aqueous polyurethane resin dispersion composition are the same as in the first embodiment of the present invention.

As a method for producing an aqueous polyurethane resin dispersion composition, an aqueous polyurethane resin dispersion can be produced by a known method described in International Publication No. 2016/039396 and the like. For example, the following manufacturing method may be mentioned.
The first production method is to obtain an aqueous polyurethane resin dispersion by mixing all raw materials with each of polyurethane resin (I) and polyurethane resin (II), reacting them, and dispersing them in an aqueous medium.
The second production method is to produce a prepolymer by reacting all polyol components and polyisocyanate in each of polyurethane resin (I) and polyurethane resin (II), and after neutralizing the acidic groups of the prepolymer, This is a method of obtaining an aqueous polyurethane resin dispersion by dispersing it in an aqueous medium and reacting it with a chain extender.
As a method for manufacturing the aqueous polyurethane resin dispersion, the second manufacturing method described above is preferred because it is easy to control the molecular weight.
Specifically, by mixing an aqueous polyurethane resin dispersion containing polyurethane resin (I) as a polyurethane resin and an aqueous polyurethane resin dispersion containing polyurethane resin (II) as a polyurethane resin, the aqueous polyurethane resin of the present invention can be produced. Dispersion compositions can also be obtained. The mixing ratio in this case is adjusted so that the content of aromatic rings and ether groups contained in all polyurethane resins falls within the above range. Even when three or more types of aqueous polyurethane resin dispersions are mixed, the aromatic rings and ether groups are adjusted to fall within the above ranges.

<Manufacture of coating material composition>
The aqueous polyurethane resin dispersion composition is used in a coating material composition.
In this specification, the coating material composition refers to a material that is applied to an electrodeposited surface, a steel plate, wood, or a plastic substrate using a spray, a brush, an applicator, a bar coater, or the like to form a coating film.

The coating material composition contains the aqueous polyurethane resin dispersion composition as an essential component, but may contain other resins and/or other additives as necessary. Hereinafter, the term "coating material composition" used herein includes not only compositions containing other resins, additives, etc., but also compositions consisting only of the aqueous polyurethane resin dispersion composition. .

Examples of the other resins include acrylic resins, olefin resins, polyester resins, vinyl chloride resins, and nylon resins in the form of emulsions. Among these, acrylic emulsions, polyolefin emulsions, and polyester emulsions are preferred, and a coating material composition obtained by mixing at least one selected from these as an optional component is a preferred form.

Examples of the other additives include coating aids, curing agents, crosslinking agents, surface conditioners, emulsifiers, thickeners, urethanization catalysts, fillers, blowing agents, pigments, dyes, oil repellents, and hollow foaming agents. A flame retardant, an antifoaming agent, a leveling agent, an antiblocking agent, etc. can be used. These additives may be used alone or in combination of two or more.

Examples of surface conditioning agents include surface conditioning agents, leveling agents, and wetting agents that have the ability to eliminate defects in coating films caused by changes in viscosity, changes in surface tension, and generation of bubbles that occur due to the increase in molecular weight. , antifoaming agents, etc. can be used without any particular restrictions. For example, acrylic, vinyl, silicone, fluorine, cellulose, natural wax, water-soluble organic solvents, etc. In addition to various surface conditioning agents, leveling agents, wetting agents, antifoaming agents, and the like, surfactants are also preferred, and wetting agents are particularly preferred.

Examples of the film forming aid include glycol ether.

The method for producing the coating material composition is not particularly limited, but any known production method can be used. For example, it is manufactured by stirring and mixing the above-mentioned aqueous polyurethane resin dispersion composition with the above-mentioned other resins and various additives as optional components.

In the coating material composition, the mixing ratio of the aqueous polyurethane resin dispersion composition and other resins is preferably 100/0 to 10/90 (solid content mass ratio) from the viewpoint of substrate adhesion and breaking energy. The ratio is more preferably 100/0 to 15/85, even more preferably 90/10 to 20/80, and particularly preferably 80/20 to 30/70.

<Curing method>
The coating material composition can be cured by heating to a temperature of 20°C or higher, preferably 100°C or lower, more preferably 80°C or lower.
Specifically, the coating material composition is sprayed or brushed onto various plastic substrates such as electrodeposited surfaces, steel plates, wood, polycarbonate resins, acrylic resins, polyethylene terephthalate (PET) resins, and acrylonitrile butadiene styrene (ABS) resins. , an applicator, a bar coater, etc., and placed in an oven, heating tank, etc. at 100°C or lower, preferably 80°C, for usually 1 to 120 minutes, preferably 1 to 60 minutes, more preferably 1 to 45 minutes, and further Curing can be carried out preferably by holding for 1 to 20 minutes. The dry thickness of the coating film is preferably adjusted to 0.5 to 200 μm, more preferably 1 to 100 μm, even more preferably 5 to 50 μm, and even more preferably 10 to 40 μm. Particularly preferred. When used as a primer, base coat, etc. in a multilayer coating film, after coating on the various substrates mentioned above, for example, at room temperature to 80°C for 1 to 30 minutes, preferably 1 to 10 minutes, more preferably, After holding for 2 to 6 minutes, apply one more base coat as an optional component, dry at the same drying temperature and time, and then apply a top coat (also called a clear coat depending on the application). It can be heated and cured at 100° C. or lower, preferably 80° C. or lower for 10 to 120 minutes, preferably 20 to 90 minutes, more preferably 30 to 60 minutes.
One embodiment of the present invention is a coating film obtained by drying the coating material composition at 20°C to 100°C after application.

<Physical properties of coating film>
The coating material composition can be dried to obtain a coating film after being applied.
The breaking energy of the coating film obtained from the coating material composition measured by the method described in the Examples is preferably 100 MPa or more, more preferably 110 MPa or more, and even more preferably 120 MPa or more. The above value can be achieved, for example, in an embodiment in which polyol (F) is used and polyester polyol (A) and polyol (F) are set in specific ranges.

The adhesion of the coating film obtained from the coating material composition to the electrodeposited surface measured by the method described in the Examples is preferably 80/100 or more, more preferably 100/100. Here, in the present invention, evaluation of adhesion of a coating film is expressed as "n/100". n means the number of squares remaining when at least one square was peeled off under the following test conditions. The conditions for the adhesion test are explained in detail in the Examples section. The above value can be achieved, for example, in an embodiment in which polyol (F) is used and polyester polyol (A) and polyol (F) are set in specific ranges.

The measured König hardness of the coating film obtained from the coating material composition, which is 13 to 15 μm obtained by drying at 80 ° C. for 10 minutes by the method described in the examples, is preferably more than 120, More preferably, it is 123 or more.

The elastic modulus of the coating film obtained from the coating material composition of the present invention, measured by the method described in the Examples, is preferably 1400 MPa or more, more preferably 1500 MPa or more, and still more preferably 2000 MPa or more. preferable.

<Application>
The coating material composition can be suitably used as a primer material, base coat material, and anti-fracture material.
In this specification, the term "destruction-resistant material" refers to a material that is used as a protectant for a base material, and which itself has characteristics that make it difficult to be destroyed by physical impact such as a collision, a stone splash, or a fall. A coating material composition containing the aqueous polyurethane resin dispersion composition of the present invention can be suitably used as a fracture-resistant material.

Primer materials, base coat materials, and anti-fracture materials are used for floor coatings, coatings on various plastic substrates or rubbers such as polycarbonate resins, acrylic resins, polyethylene terephthalate (PET) resins, acrylonitrile butadiene styrene (ABS) resins, and steel plate treatments. It is useful in a wide range of applications, such as primers or base coats for the exterior of metals such as agents, automobiles, trucks, trains and other vehicles, and is particularly useful for primers or base coats for the exterior of metals.

[Third aspect of the present invention]
A third aspect of the present invention is a structural unit derived from a polyester polyol (A) containing a polyol (Aa) and a dicarboxylic acid (Ab), a structural unit derived from a polyether polyol (G), and a polyisocyanate (B). ) has a constituent unit derived from
At least one member selected from the group consisting of the structural unit derived from the polyester polyol (A), the structural unit derived from the polyether polyol (G), and the structural unit derived from the polyisocyanate (B) has an aromatic ring. ,
A polyurethane resin in which the aromatic rings in the polyurethane resin are 4% by mass to 18% by mass, and the ether groups in the polyurethane resin are 0.5% by mass to 10% by mass.
This polyurethane resin, its constituent units, and manufacturing method are the same as those of the polyurethane resin in the aqueous polyurethane resin dispersion composition of the first aspect of the present invention.
This polyurethane resin forms a coating film. The physical properties and uses of this coating film are the same as those of the coating material composition described above.

[Fourth aspect of the present invention]
A polyurethane resin composition containing two or more types of polyurethane resins,
At least one type of polyurethane resin has a structural unit derived from a polyester polyol (A) containing a polyol (Aa) and a dicarboxylic acid (Ab) and a structural unit derived from a polyisocyanate (B), and the polyurethane resin It has an aromatic ring inside,
At least one type of polyurethane resin has a structural unit derived from a polyether polyol (G) and a structural unit derived from a polyisocyanate (B),
A polyurethane resin composition in which the content of aromatic rings is 4% by mass to 18% by mass and the content of ether bonds is 0.5% by mass to 10% by mass in the total polyurethane resin.
The structural units and manufacturing method of the polyurethane resin in this polyurethane resin composition are the same as those for the polyurethane resin in the aqueous polyurethane resin dispersion composition of the second aspect of the present invention.
This polyurethane resin forms a coating film. The physical properties and uses of this coating film are the same as those of the coating material composition described above.

EXAMPLES The present invention will be explained in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited thereto.
The physical properties were measured as follows.

(1) The weight average molecular weight of the polyurethane resin in the aqueous polyurethane resin dispersion composition was measured by gel permeation chromatography (GPC), and the converted value obtained from a standard polystyrene calibration curve prepared in advance was recorded. did.
(2) Acid value was measured in accordance with JIS K 1557 indicator titration method.

(3) The Koenig hardness of the coating film was evaluated as follows. Each aqueous polyurethane resin dispersion composition contains 2% by mass of dipropylene glycol n-butyl ether (DOWANOL (registered trademark) DPnB manufactured by Ando Parachemy) as a film-forming agent, and a silicone surfactant (BYK manufactured by BYK A coating material composition prepared by adding and mixing 0.5% by mass of -345) was uniformly applied onto a cationic electrodeposition coating plate for automobiles manufactured by Nippon Test Panel using a bar coater #20. . Then, it was dried at 80°C for 10 minutes. The thickness of the resulting coating film was 13 to 15 μm. In the laminate of the electrocoated plate and the polyurethane resin coating obtained above, the Koenig hardness of the polyurethane resin coating was measured by a method based on ISO 1522.

(4) The adhesion of the coating film to the electrodeposited layer surface was evaluated as follows. In the aqueous polyurethane resin dispersion composition, Dowanol (registered trademark) DPnB was added as a film-forming agent to 2% by mass of the total, and a silicone surfactant (manufactured by BYK Chemie, BYK-345) was added to 0.5% by mass of the total. The coating material composition added and mixed was applied onto an automobile steel sheet cationic electrodeposited plate (manufactured by Nippon Test Panel Co., Ltd.) using a bar coater #18, and heated and dried at 80°C for 45 minutes. A checkerboard peel test was conducted using the membrane. Cuts were made in the coating film at 1 mm intervals vertically and horizontally in an area of 10 mm x 10 mm, adhesive tape was applied, and the number of squares remaining on the surface of the electrodeposited layer was visually counted and evaluated when it was peeled off. For example, when 15 out of 100 pieces remained in the peel test, it was written as 15/100.

(5) The tensile properties of the coating film were evaluated as follows. In the aqueous polyurethane resin dispersion composition, 4.7% by mass of Dowanol (registered trademark) DPnB was added as a film-forming agent, and 0.5% of the total amount of silicone surfactant (BYK-345, manufactured by BYK Chemie) was added to the aqueous polyurethane resin dispersion composition. The coating material composition added and mixed in a mass % was applied onto a PET film so that the dry film thickness was 70 μm. Next, after being left at room temperature for 15 hours, it was dried at 60°C for 2 hours and then at 120°C for 2 hours to form a coating film. The elastic modulus of the polyurethane resin film was measured according to JIS K 7311. The breaking energy of the coating film was determined by integrating the stress from zero elongation to the elongation at break on the elongation-stress curve. Note that the measurement conditions were a measurement temperature of 23° C., humidity of 50%, and a tensile speed of 100 mm/min.

(6) The ratio of aromatic rings and ether bonds in the polyurethane resin was determined from the following formula based on the amount charged.
Content of aromatic ring structure (mass%) = 100 x (atomic weight of carbon x 6 + atomic weight of hydrogen x 4) x {(number of moles [mol] of polyester polyol (A)) x (contained in polyester polyol (A) (number of aromatic rings contained in polyisocyanate (B)) + (number of moles [mol] of polyisocyanate (B)) × (number of aromatic rings contained in polyisocyanate (B)) + (number of moles of acidic group-containing polyol (C) [mol] mol]) × (Number of aromatic rings contained in acidic group-containing polyol (C)) + (Number of moles [mol] of chain extender (E)) × (Aromatic ring contained in chain extender (E) ) + (number of moles of polyol (F) [mol]) × (number of aromatic rings contained in polyol (F)) + (number of moles of polyether polyol (G) [mol]) × (polyether Polyol (G) number of aromatic rings contained)}/(mass of polyurethane resin [g])
Content of ether bonds (mass%) = 100 x (atomic weight of oxygen x 1) x {(number of moles [mol] of polyester polyol (A)) x (number of ether bonds contained in polyester polyol (A)) + (Number of moles [mol] of polyisocyanate (B)) x (number of ether bonds contained in polyisocyanate (B)) + (number of moles [mol] of acidic group-containing polyol (C)) x (polyol containing acidic group) (Number of ether bonds contained in (C)) + (Number of moles [mol] of chain extender (E)) x (Number of ether bonds contained in chain extender (E)) + (Mole of polyol (F) number [mol]) x (number of ether bonds contained in polyol (F)) + (number of moles [mol] of polyether polyol (G)) x (number of ether bonds contained in polyether polyol (G)) }/(mass of polyurethane resin [g])
(7) The number average molecular weight and hydroxyl value of raw materials are catalog values.

[Manufacture example 1]
<Production of aqueous polyurethane resin dispersion composition (1)>
Polyester polyol HS (registered trademark) 2F-136P (manufactured by Toyokuni Oil Co., Ltd.; LOT.GL7832; number average molecular weight 1079; hydroxyl value 104.0 mgKOH/g; acid value 0.81; obtained by dehydration condensation of neopentyl glycol and terephthalic acid. polyester polyol, 152 g), polytetramethylene ether glycol (PTMG, manufactured by Mitsubishi Chemical; number average molecular weight 1955; hydroxyl value 57.4 mgKOH/g, 38.0 g), and 2,2-dimethylolpropionic acid (28 .0g) and 4,4'-dicyclohexylmethane diisocyanate (181.6g) in dipropylene glycol dimethyl ether (DMM, 102.2g) in the presence of dibutyltin dilaurylate (0.0606g) under a nitrogen atmosphere, Heated at 80-85°C for 4 hours. The reaction mixture was cooled to 80° C., triethylamine (21.1 g) was added and mixed, and 362.7 g of the mixture was added to water (569.6 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (60.6g) and 35% by mass 2-(2-aminoethylamino)ethanol (8.0g) were added to form an aqueous polyurethane resin. Dispersion composition (1) (polyurethane resin weight average molecular weight 460,000, acid value 27.0) was obtained.

[Manufacture example 2]
<Production of aqueous polyurethane resin dispersion composition (2)>
Polyester polyol HS (registered trademark) 2F-136P (manufactured by Toyokuni Oil Co., Ltd.; LOT.GL7832; number average molecular weight 1079; hydroxyl value 104.0 mgKOH/g; acid value 0.81; obtained by dehydration condensation of neopentyl glycol and terephthalic acid. polyester polyol, 117.0 g), polytetramethylene ether glycol (PTMG, manufactured by Mitsubishi Chemical; number average molecular weight 1955; hydroxyl value 57.4 mgKOH/g, 78.2 g), and 2,2-dimethylolpropionic acid. (27.8 g) and 4,4'-dicyclohexylmethane diisocyanate (175.3 g) in dipropylene glycol dimethyl ether (DMM, 101.1 g) in the presence of dibutyltin dilaurylate (0.0817 g) under a nitrogen atmosphere. The mixture was heated at 80 to 85°C for 5 hours. The reaction mixture was cooled to 80° C., triethylamine (20.6 g) was added and mixed, and 364.5 g of the mixture was added to water (572.5 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (56.0g) and 35% by mass 2-(2-aminoethylamino)ethanol (8.0g) were added to form an aqueous polyurethane resin. Dispersion composition (2) (polyurethane resin weight average molecular weight 790,000, acid value 27.0) was obtained.

[Manufacture example 3]
<Production of aqueous polyurethane resin dispersion composition (3)>
Polyester polyol HS (registered trademark) 2F-136P (manufactured by Toyokuni Oil Co., Ltd.; LOT.GL0734; number average molecular weight 1090; hydroxyl value 103.0 mgKOH/g; acid value 0.74; obtained by dehydration condensation of neopentyl glycol and terephthalic acid. polyester polyol, 96.1 g), polytetramethylene ether glycol (PTMG, manufactured by Mitsubishi Chemical; number average molecular weight 1955; hydroxyl value 57.4 mgKOH/g, 64.1 g), and 2,2-dimethylolpropionic acid. (36.9 g) and 4,4'-dicyclohexylmethane diisocyanate (195.2 g) in dipropylene glycol dimethyl ether (DMM, 100.0 g) in the presence of dibutyltin dilaurylate (0.1536 g) under a nitrogen atmosphere. The mixture was heated at 80 to 85°C for 5 hours. The reaction mixture was cooled to 80° C., triethylamine (27.3 g) was added and mixed, and 365.5 g of the mixture was added to water (562.5 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (57.2g) and 35% by mass 2-(2-aminoethylamino)ethanol (15.9g) were added to form an aqueous polyurethane resin. Dispersion composition (3) (polyurethane resin weight average molecular weight 870,000, acid value 36.0) was obtained.

[Manufacture example 4]
<Production of aqueous polyurethane resin dispersion composition (4)>
Polytetramethylene ether glycol (PTMG, manufactured by Mitsubishi Chemical; number average molecular weight 1968; hydroxyl value 57.0 mgKOH/g, 50.5 kg), 2,2-dimethylolpropionic acid (1.9 kg), and isophorone diisocyanate (12 .6 kg) in dipropylene glycol dimethyl ether (DMM, 18.5 kg) under a nitrogen atmosphere at 80-90° C. for 7.5 hours. The reaction mixture was cooled to 80° C., triethylamine (1.5 kg) was added and mixed, and 79.7 kg of the mixture was added to water (126.1 kg) under strong stirring. Next, piperazine (1.2 kg) was added to prepare the aqueous polyurethane resin dispersion composition (4) (weight average molecular weight of polyurethane resin: 880,000, acid value: 12.2).

[Manufacture example 5]
<Production of aqueous polyurethane resin dispersion composition (5)>
Polyester polyol HS (registered trademark) 2F-136P (manufactured by Toyokuni Oil Co., Ltd.; LOT.GL7832; number average molecular weight 1079; hydroxyl value 104.0 mgKOH/g; acid value 0.81; obtained by dehydration condensation of neopentyl glycol and terephthalic acid. dipropylene glycol dimethyl ether (DMM, 142g), 2,2-dimethylolpropionic acid (27.5g), and 4,4'-dicyclohexylmethane diisocyanate (184.7g). The mixture was heated at 80 to 85° C. for 4.5 hours in the presence of dibutyltin dilaurylate (0.1512 g) in a nitrogen atmosphere. The reaction mixture was cooled to 80° C., triethylamine (20.4 g) was added and mixed, and 392.4 g of the mixture was added to water (541.5 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (59.7g) and 35% by mass 2-(2-aminoethylamino)ethanol (8.0g) were added to form an aqueous polyurethane resin. Dispersion composition (5) (weight average molecular weight of polyurethane resin 690,000, acid value 27.2)

[Manufacture example 6]
<Production of aqueous polyurethane resin dispersion composition (6)>
A polyester polyol obtained by dehydration condensation of hexanediol and isophthalic acid (number average molecular weight 1000; hydroxyl value 112.2 mgKOH/g; acid value 0.04, 180.1 g) and 2,2-dimethylolpropionic acid ( 28.7 g) and 4,4'-dicyclohexylmethane diisocyanate (192.4 g) in dipropylene glycol dimethyl ether (DMM, 145.0 g) in the presence of dibutyltin dilaurylate (0.1348 g) under a nitrogen atmosphere. , and heated at 80-85° C. for 4.5 hours. The reaction mixture was cooled to 80° C., triethylamine (21.4 g) was added and mixed, and 392.5 g of the mixture was added to water (539.9 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (62.7g) and 35% by mass 2-(2-aminoethylamino)ethanol (8.0g) were added to form an aqueous polyurethane resin. Dispersion composition (6) (weight average molecular weight of polyurethane resin 660,000, acid value 27.5)

[Manufacture example 7]
<Production of aqueous polyurethane resin dispersion composition (7)>
ETERNACOLL (registered trademark) UM90 (3/1) (manufactured by Ube Industries; number average molecular weight 903; hydroxyl value 124.3 mgKOH/g; 1,4-cyclohexanedimethanol, 1,6-hexanediol (3:1 molar ratio) ) and carbonate ester, 152.1 g) and polytetramethylene ether glycol (PTMG, manufactured by Mitsubishi Chemical; number average molecular weight 1955; hydroxyl value 57.4 mgKOH/g, 37.9 g) , 2,2-dimethylolpropionic acid (29.7 g), and 4,4'-dicyclohexylmethane diisocyanate (202.8 g) were dissolved in dibutyltin dilaurylate ( 0.1837g) under a nitrogen atmosphere at 80-85°C for 5 hours. The reaction mixture was cooled to 80° C., triethylamine (22.2 g) was added and mixed, and 365.3 g of the mixture was added to water (569.6 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (62.2g) and 35% by mass 2-(2-aminoethylamino)ethanol (8.0g) were added to form an aqueous polyurethane resin. Dispersion composition (7) (weight average molecular weight of polyurethane resin 710,000, acid value 27.0)

[Manufacture example 8]
<Production of aqueous polyurethane resin dispersion composition (8)>
ETERNACOLL (registered trademark) UM90 (3/1) (manufactured by Ube Industries; number average molecular weight 903; hydroxyl value 124.3 mgKOH/g; 1,4-cyclohexanedimethanol, 1,6-hexanediol (3:1 molar ratio) ) and carbonate ester (113.7 g) and polytetramethylene ether glycol (PTMG, manufactured by Mitsubishi Chemical; number average molecular weight 1955; hydroxyl value 57.4 mgKOH/g, 76.0 g) , 2,2-dimethylolpropionic acid (28.4 g), and 4,4'-dicyclohexylmethane diisocyanate (185.2 g) were dissolved in dibutyltin dilaurylate ( 0.1323g) under a nitrogen atmosphere at 80-85°C for 4.5 hours. The reaction mixture was cooled to 80° C., triethylamine (21.2 g) was added and mixed, and 365.7 g of the mixture was added to water (570.7 g) under strong stirring. Next, 35% by mass 2-methyl-1,5-pentanediamine aqueous solution (59.7g) and 35% by mass 2-(2-aminoethylamino)ethanol (8.0g) were added to form an aqueous polyurethane resin. Dispersion composition (8) (weight average molecular weight of polyurethane resin 740,000, acid value 27.2)

[Manufacture example 9]
<Production of aqueous polyurethane resin dispersion composition blend product (9)>
0.29 g of the aqueous polyurethane resin dispersion composition (4) and 4.71 g of the aqueous polyurethane resin dispersion composition (5) were stirred and mixed to obtain an aqueous polyurethane resin dispersion composition (9).

[Manufacture example 10]
<Production of aqueous polyurethane resin dispersion composition blend product (10)>
0.29 g of the aqueous polyurethane resin dispersion composition (4) and 4.71 g of the aqueous polyurethane resin dispersion composition (6) were stirred and mixed to obtain an aqueous polyurethane resin dispersion composition (10).

[Examples 1 to 5, Comparative Examples 1 to 4]
Using the aqueous polyurethane resin dispersion composition and its composition described above, a coating film was prepared by the method described above, and the Koenig hardness, adhesion to the electrodeposited layer surface, and tensile properties were measured. The results are shown in Table 1.

As shown in Examples 1 to 5 in Table 1, the coating film obtained by applying and heat-treating the aqueous urethane resin dispersion of the present invention has a high Koenig's resistance when dried at a low temperature and short time of 10 minutes at 80°C. Expresses hardness. By keeping the aromatic ring concentration and ether group concentration within a certain range, it is possible to maintain high König hardness while drying at a low temperature and short time of 10 minutes at 80°C, while improving adhesion and elastic modulus to the electrodeposited surface. (See Examples 1 to 5).
On the other hand, when the polyurethane resin does not contain any ether groups, the adhesion is low (see Comparative Examples 1 and 2).
Furthermore, if the polyurethane resin does not contain any aromatic rings, the elastic modulus and hardness will be low (see Comparative Examples 3 and 4).

The composition containing the aqueous urethane resin dispersion of the present invention can be dried at a low temperature of 100°C or less in a short time, and the adhesion and flexibility of the coating film obtained from the composition containing the aqueous urethane resin dispersion are improved. Due to its high hardness, it is expected to contribute to reducing global warming gas emissions by drying floor coatings, coatings on plastic substrates or rubber, steel plate treatment agents, and vehicle primer layers by drying them at low temperatures.

Claims (25)

An aqueous polyurethane resin dispersion composition comprising a polyurethane resin and an aqueous medium,
The polyurethane resin has a structural unit derived from a polyester polyol (A) whose constituent components are a polyol (Aa) and a dicarboxylic acid (Ab), a structural unit derived from a polyether polyol (G), and a structure derived from a polyisocyanate (B). unit, and has an aromatic ring in the polyurethane resin,
An aqueous polyurethane resin dispersion composition, wherein the content of aromatic rings in the polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass to 10% by mass. An aqueous polyurethane resin dispersion composition containing two or more types of polyurethane resins and an aqueous medium, wherein at least one type of polyurethane resin is a polyester polyol (Aa) containing a polyol (Aa) and a dicarboxylic acid (Ab) as constituent components. ) has a structural unit derived from polyisocyanate (B), and has an aromatic ring in the polyurethane resin, and at least one polyurethane resin contains structural units derived from polyether polyol (G) and a structural unit derived from polyisocyanate (B), and has an aromatic ring in the polyurethane resin. It has a structural unit derived from isocyanate (B), the content of aromatic rings is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass to 10% by mass in the entire polyurethane resin. An aqueous polyurethane resin dispersion composition. The aqueous polyurethane resin dispersion composition according to claim 1 or 2, wherein the polyurethane resin further has a structural unit derived from the acidic group-containing polyol (C) and a structural unit derived from the chain extender (E). The aqueous polyurethane resin dispersion composition according to claim 1 or 2, wherein the dicarboxylic acid (Ab) contains an aromatic dicarboxylic acid. The aqueous polyurethane resin dispersion composition according to claim 1 or 2, which has structural units derived from a polyol (F) other than the polyester polyol (A), the acidic group-containing polyol, and the polyether polyol (G). The aqueous polyurethane resin dispersion composition according to claim 4, wherein the two carboxyl groups in the aromatic dicarboxylic acid are in a para-position relationship on a benzene ring. The aqueous polyurethane resin dispersion composition according to claim 5, wherein the polyol (F) is a polycarbonate polyol. The aqueous polyurethane resin dispersion composition according to claim 4, wherein the polyether polyol (G) and the polyol (F) have two hydroxyl groups. The aqueous polyurethane resin dispersion composition according to claim 3, wherein the chain extender (E) is a polyamine. The aqueous polyurethane resin dispersion composition according to claim 1, wherein the mass ratio of the polyester polyol (A) and the polyether polyol (G) is 50:50 to 90:10. The aqueous polyurethane resin dispersion composition according to claim 1 or 2, which contains 50 to 100% by mass of an alicyclic polyisocyanate in the total amount of the polyisocyanate (B). The aqueous polyurethane resin dispersion composition according to claim 1 or 2, wherein the polyurethane resin has a weight average molecular weight of 100,000 or more. The aqueous polyurethane resin dispersion composition according to claim 1 or 2, wherein the dicarboxylic acid (Ab) has a hydroxyl value of 55 to 140 mgKOH/g. A coating material composition comprising the aqueous polyurethane resin dispersion composition according to claim 1 or 2. A coating film obtained by drying the coating material composition according to claim 14 after application. Claim 15, wherein no peeling is observed when the coating film obtained by drying the coating material composition at 80° C. for 45 minutes is subjected to a checkerboard peeling test of the coating film on the electrodeposited surface. The coating film described. A method for producing a coating film, comprising the step of drying the coating material composition according to claim 14 at 20°C to 100°C. 15. A coating material composition according to claim 14 for a metal exterior primer or base coat. Coating material composition according to claim 14 for materials with anti-fracture properties. Coating material composition according to claim 15 for coatings according to claim 15, floor coats, plastic or rubber coats. A steel plate treatment agent containing the coating material composition according to claim 14. It has a structural unit derived from a polyester polyol (A) containing a polyol (Aa) and a dicarboxylic acid (Ab), a structural unit derived from a polyether polyol (G), and a structural unit derived from a polyisocyanate (B), and has an aromatic ring in the polyurethane resin, the content of the aromatic ring in the polyurethane resin is 4% by mass to 18% by mass, and the content of ether bonds is 0.5% by mass to 10% by mass. , polyurethane resin. A coating film containing the polyurethane resin according to claim 22. A polyurethane resin composition containing two or more types of polyurethane resins, in which at least one type of polyurethane resin contains structural units derived from a polyester polyol (A) containing a polyol (Aa) and a dicarboxylic acid (Ab) as constituent components; It has a structural unit derived from polyisocyanate (B), and has an aromatic ring in the polyurethane resin, and at least one polyurethane resin has a structural unit derived from polyether polyol (G) and a polyisocyanate (B)-derived structural unit. It has a constituent unit,
A polyurethane resin composition in which the content of aromatic rings is 4% by mass to 18% by mass and the content of ether bonds is 0.5% by mass to 10% by mass in the total polyurethane resin. A coating film containing the polyurethane resin composition according to claim 24.