JP7411363B2 - Paint film and coating base material - Google Patents

Description

The present invention relates to polyisocyanate compositions, coating compositions and coating substrates.

The two-component polyurethane coating composition is curable at room temperature, and the resulting coating film has excellent abrasion resistance, chemical resistance, and stain resistance. In recent years, in view of environmental conservation, it has been desired to convert the room-temperature crosslinking two-component urethane coating composition, which was conventionally used as a solvent-based paint, into a water-based one.
Polyisocyanates modified with anions to impart hydrophilic properties are characterized by easy dispersibility in water and are gaining increasing acceptance in many fields. Many methods for producing such water-dispersible polyisocyanates have been reported so far.

For example, Patent Document 1 discloses a reaction product of a polyisocyanate compound and a compound having at least one sulfonic acid group and an isocyanate group.
Patent Document 2 and Patent Document 3 disclose a polyisocyanate composition containing a modified polyisocyanate obtained by reacting an amine salt of a sulfonic acid having a hydroxyl group with a polyisocyanate.
Patent Documents 4 and 5 disclose modified polyisocyanates obtained by reacting aminosulfonic acids with specific structures with polyisocyanates.

Japanese Unexamined Patent Publication No. 8-176267 Japanese Patent Application Publication No. 2015-205957 Japanese Patent Application Publication No. 2016-017157 Patent No. 4806511 International Publication No. 2015/035673

Water-based two-component urethane coating compositions are used for painting furniture and building materials, residential woodwork, wooden floors of houses and school facilities, trains and construction machinery, agricultural vehicles, and the like. There is a need for polyisocyanate compositions that provide coatings with excellent appearance, hardness, water resistance, and stain resistance.

In the polyisocyanate composition described in Patent Document 1, it is difficult to achieve both excellent pot life and dispersibility when dispersed in water or a base agent containing water.
Patent Documents 2 and 3 disclose that the dispersibility in water is improved by using a polyisocyanate containing a sulfonic acid group. However, since the compatibility between the sulfonic acid group and the polyisocyanate is poor, there is a problem in that the synthetic product becomes cloudy. If a highly organic sulfonic acid or its amine salt is used to improve this turbidity, the appearance of the paint film will deteriorate, and a large amount of the sulfonic acid or its amine salt must be modified, resulting in insufficient water resistance and the paint film. There is also the problem that the hardness of the material decreases.
Patent Documents 4 and 5 disclose that the hardness of the coating film and the solvent resistance of the coating film can be improved by using a modified polyisocyanate obtained by reaction with an aminosulfonic acid having a specific structure. On the other hand, since the aminosulfonic acid having a specific structure has relatively high hydrophobicity, there is a problem that the appearance of the coating film becomes poor. Another problem is that although aminosulfonic acid has relatively high hydrophobicity, it has poor water resistance and stain resistance.

The present invention has been made in view of the above circumstances, and is a polyester resin that can obtain excellent pot life and dispersibility when dispersed in water or a main agent containing water, and has an excellent appearance when formed into a coating film. An isocyanate composition is provided. A coating composition and coating substrate using the polyisocyanate composition are provided.

That is, the present invention includes the following aspects.
The polyisocyanate composition according to the first aspect of the present invention includes a polyisocyanate containing a sulfonic acid anion group in the molecule and a tertiary ammonium cation of an amine compound represented by the following general formula (1). In the polyisocyanate composition, the molar ratio of the sulfonic acid anion group to the tertiary ammonium cation is 0.8 or more and 0.99 or less.

(In general formula (1), R ¹¹ , R ¹² and R ¹³ are each independently a hydrocarbon group having 1 to 10 carbon atoms and which may contain an ether bond. ^{R 11} , R ¹² and R ¹³ At least one selected from the group consisting of may include a ring structure, and two or more selected from the group consisting of R ¹¹ , R ¹² and R ¹³ may be bonded to each other to form a ring structure. The structure is an aromatic ring, a cycloalkyl group having 5 or 6 carbon atoms, a 5- or 6-membered ring in which R ¹¹ and R ¹² are bonded to each other, or a structure in which R ¹¹ , R ¹² , and R ¹³ are bonded to each other. It is a multi-membered ring.)

The molar ratio of the sulfonic acid anion group to the tertiary ammonium cation may be 0.9 or more and 0.99 or less.
The polyisocyanate may have an isocyanurate group.
The polyisocyanate containing a sulfonic acid anion group in the molecule is obtained by a reaction between an amine salt of a sulfonic acid having a hydroxyl group and a polyisocyanate, and the amine salt of a sulfonic acid having a hydroxyl group has a hydroxyl group. It may also be a salt of a sulfonic acid and an amine compound represented by the general formula (1).
The sulfonic acid having a hydroxyl group may be a compound represented by the following general formula (2).

(In general formula (2), R ²¹ is a hydrocarbon group having 1 to 10 carbon atoms that may contain at least one selected from the group consisting of a hydroxyl group, an ether bond, an ester bond, a carbonyl group, and an imino group. ^R21 may include a ring structure.The ring structure is an aromatic ring, a 5- or 6-membered ring containing two nitrogen atoms, or a 5- or 6-membered ring containing a nitrogen atom and an oxygen atom. It is a member ring.)

The polyisocyanate may be at least one selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, and araliphatic polyisocyanates.

The coating composition according to the second aspect of the present invention includes the polyisocyanate composition according to the first aspect.

The coated substrate according to the second aspect of the present invention is coated with the coating composition according to the second aspect.

According to the polyisocyanate composition of the above aspect, it is possible to provide a polyisocyanate composition that can obtain excellent pot life and dispersibility when dispersed in water or a main ingredient containing water. The coating composition of the above embodiment contains the polyisocyanate composition and has an excellent appearance when formed into a coating film. The coated substrate of the above embodiment includes a coating film formed by curing the coating composition, and the coating film has an excellent appearance.

Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "this embodiment") will be described in detail. Note that the present invention is not limited to the following embodiment. The present invention can be implemented with appropriate modifications within the scope of its gist.

≪Polyisocyanate composition≫
The polyisocyanate composition of the present embodiment includes a polyisocyanate containing a sulfonic acid anion group in the molecule and an amine compound represented by the following general formula (1) (hereinafter sometimes referred to as "amine compound (1)"). and a tertiary ammonium cation.

(In general formula (1), R ¹¹ , R ¹² and R ¹³ are each independently a hydrocarbon group having 1 to 10 carbon atoms and which may contain an ether bond. ^{R 11} , R ¹² and R ¹³ At least one selected from the group consisting of may include a ring structure, and two or more selected from the group consisting of R ¹¹ , R ¹² and R ¹³ may be bonded to each other to form a ring structure. The structure is an aromatic ring, a cycloalkyl group having 5 or 6 carbon atoms, a 5- or 6-membered ring in which R ¹¹ and R ¹² are bonded to each other, or a structure in which R ¹¹ , R ¹² , and R ¹³ are bonded to each other. It is a multi-membered ring.)

Further, in the polyisocyanate composition of the present embodiment, the molar ratio of the sulfonic acid anion group (sulfonic acid anion group/tertiary ammonium cation) to the tertiary ammonium cation is 0.8 or more and 0.99 or less. , preferably 0.85 or more and 0.99 or less, more preferably 0.9 or more and 0.99 or less, and even more preferably 0.95 or more and 0.99 or less.
When the molar ratio of sulfonic acid anion group/tertiary ammonium cation is within the above range, the pot life of the polyisocyanate composition tends to be better, and the appearance when formed into a coating film tends to be better. The molar ratio of sulfonic acid anion group/tertiary ammonium cation can be adjusted by changing the blending amount of tertiary ammonium cation in the polyisocyanate and amine compound (1) containing sulfonic acid anion group in the molecule. The molar ratio of anion group/tertiary ammonium cation can be adjusted within the above range. The molar ratio of sulfonic acid anion group/tertiary ammonium cation can be calculated using the method described in the Examples below.

By having the above structure, the polyisocyanate composition of the present embodiment can obtain excellent dispersibility when dispersed in water or a main agent containing water, as shown in Examples below. Moreover, by using the polyisocyanate composition of this embodiment, a coating film with excellent pot life and appearance can be obtained.
In addition, "pot life" as used herein refers to ensuring the performance of a composition before curing after the composition is prepared by mixing the main ingredient and curing agent in compositions such as paints and adhesives. means time. Also called pot life. As shown in the examples below, by measuring the time during which 80% or more of the isocyanate groups in the coating composition prepared by mixing the polyisocyanate composition (curing agent) of this embodiment and the main agent are retained, can be evaluated.
The constituent components of the polyisocyanate composition of this embodiment will be explained in detail.

<Isocyanate component>
The polyisocyanate composition of the present embodiment usually contains unreacted polyisocyanate, that is, polyisocyanate that does not contain a sulfonic acid anion group in the molecule, as an isocyanate component. In addition, various properties of the polyisocyanate composition of the present embodiment described below are based on polyisocyanate containing a sulfonic acid anion group in the molecule and unreacted polyisocyanate (having a sulfonic acid anion group in the molecule) unless otherwise specified. This is the property in a state containing polyisocyanate).

In the polyisocyanate composition of the present embodiment, the ratio of unreacted polyisocyanate to polyisocyanate containing a sulfonic acid anion group in the molecule is, for example, relative to 100 moles of isocyanate groups in the raw material polyisocyanate. It can be calculated from the proportion of isocyanate groups containing sulfonic acid anion groups in the molecule.

[Polyisocyanate containing sulfonic acid anion group in the molecule]
The polyisocyanate containing a sulfonic acid anion group in the molecule contained in the polyisocyanate composition of the present embodiment is a reaction product obtained by reacting a sulfonic acid having a hydroxyl group or an amine salt thereof with a polyisocyanate. A reaction product obtained by reacting a sulfonic acid amine salt having the following with a polyisocyanate is preferable. Furthermore, the amine salt of a sulfonic acid having a hydroxyl group is preferably a salt of a sulfonic acid having a hydroxyl group and the amine compound (1).

(Polyisocyanate)
The polyisocyanate used for the polyisocyanate containing a sulfonic acid anion group in the molecule is not particularly limited, but for example, a polyisocyanate derived from at least one diisocyanate selected from aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates. Examples include polyisocyanates. The polyisocyanate used for the polyisocyanate containing a sulfonic acid anion group in the molecule is selected from the group consisting of aliphatic polyisocyanate, alicyclic polyisocyanate, and aromatic polyisocyanate from the viewpoint of industrial availability. It is preferable that it is at least one type.

Examples of aliphatic diisocyanates include, but are not limited to, 1,4-diisocyanatobutane, 1,5-diisocyanatopentane, ethyl (2,6-diisocyanato)hexanoate, 1,6-diisocyanatohexane ( (hereinafter sometimes referred to as "HDI"), 1,9-diisocyanatononane, 1,12-diisocyanatododecane, 2,2,4- or 2,4,4-trimethyl-1,6-di Examples include isocyanatohexane.

The alicyclic diisocyanate is not particularly limited, but includes, for example, 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane (hereinafter sometimes referred to as "hydrogenated XDI"), 1,3- or 1,4-diisocyanatocyclohexane, 3,5,5-trimethyl 1-isocyanato-3-(isocyanatomethyl)cyclohexane (hereinafter sometimes referred to as "IPDI"), 4-4'-diisocyanato-dicyclohexylmethane (hereinafter sometimes referred to as "hydrogenated MDI"), 2,5- or 2,6-diisocyanatomethylnorbornane, and the like.

Examples of aromatic diisocyanates include, but are not limited to, xylylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and the like.

Among these, preferred diisocyanates are HDI, IPDI, hydrogenated XDI, and hydrogenated MDI.

Polyisocyanates derived from the above diisocyanates are not particularly limited, but include, for example, the polyisocyanates shown in (a) to (h) below.
(a) A polyisocyanate having a uretdione group obtained by cyclizing and dimerizing two isocyanate groups;
(b) a polyisocyanate having an isocyanurate group or an iminooxadiazinedione group obtained by cyclizing and trimerizing three isocyanate groups;
(c) a polyisocyanate having a biuret group obtained by reacting three isocyanate groups and one water molecule;
(d) a polyisocyanate having an oxadiazinetrione group obtained by reacting two isocyanate groups with one molecule of carbon dioxide;
(e) polyisocyanate having a plurality of urethane groups obtained by reacting one isocyanate group with one hydroxyl group;
(f) a polyisocyanate having an allophanate group obtained by reacting two isocyanate groups and one hydroxyl group;
(g) a polyisocyanate having an acylurea group obtained by reacting one isocyanate group and one carboxyl group;
(h) Polyisocyanate having a urea group obtained by reacting one isocyanate group with one primary or secondary amine

Among them, the polyisocyanate used in the polyisocyanate containing a sulfonic acid anion group in the molecule is preferably the one mentioned above, and a polyisocyanate having an isocyanurate group is more preferable.

Further, the polyisocyanate used for the polyisocyanate containing a sulfonic acid anion group in the molecule may include an aliphatic triisocyanate. Examples of the aliphatic triisocyanate include 1,3,6-triisocyanatohexane, 1,8-diisocyanato-4-isocyanatomethyloctane, 2-isocyanatoethyl-2,6-diisocyanato-hexanoate, and the like. It will be done.

Further, these polyisocyanates may be modified with a nonionic hydrophilic group such as alkoxypolyalkylene glycol or a vinyl polymer having a hydroxyl group and a nonionic hydrophilic group.

Further, these polyisocyanates can be used alone or in combination of two or more.

・Method for producing polyisocyanate The method for producing polyisocyanate containing an isocyanurate group is not particularly limited, but for example, diisocyanate is subjected to an isocyanurate reaction using a catalyst, etc., and when a predetermined conversion rate is reached, the reaction is stopped. Examples include a method of stopping the reaction and removing unreacted diisocyanate.

The catalyst used in the above-mentioned isocyanurate reaction is not particularly limited, but it is preferable to use one that shows basicity. Examples include weak acid salts, alkali metal salts of alkylcarboxylic acids, metal alcoholates, aminosilyl group-containing compounds, Mannich bases, combinations of tertiary amines and epoxy compounds, phosphorus compounds, and the like.
Examples of the tetraalkylammonium include tetramethylammonium and tetraethylammonium.
Examples of organic weak acids include acetic acid, capric acid, and the like.
Examples of the hydroxyalkylammonium include trimethylhydroxypropylammonium, trimethylhydroxyethylammonium, triethylhydroxypropylammonium, and triethylhydroxyethylammonium.
Examples of alkylcarboxylic acids include acetic acid, caproic acid, octylic acid, myristic acid, and the like.
Examples of the alkali metal salt include tin, zinc, and lead.
Examples of the metal alcoholate include sodium alcoholate and potassium alcoholate.
Examples of the aminosilyl group-containing compound include hexamethyldisilazane.
Examples of the phosphorus compound include tributylphosphine.

The amount of these catalysts used is preferably 10 ppm or more and 1.0% or less based on the total mass of the diisocyanate (and alcohol, if necessary) that is the raw material. Further, in order to terminate the isocyanurate reaction, the catalyst may be inactivated by addition of an acidic substance that neutralizes the catalyst, thermal decomposition, chemical decomposition, or the like. Examples of the acidic substance that neutralizes the catalyst include phosphoric acid, acidic phosphoric acid ester, and the like.

The yield of polyisocyanate generally tends to be 10% by mass or more and 70% by mass or less. Polyisocyanates obtained in higher yields tend to have higher viscosities. The yield can be calculated from the ratio of the mass of the obtained polyisocyanate to the total mass of raw material components.

The reaction temperature of the isocyanurate reaction is not particularly limited, but is preferably 50°C or higher and 200°C or lower, more preferably 50°C or higher and 150°C or lower. When the reaction temperature is above the above lower limit, the reaction tends to proceed more easily, and when the reaction temperature is below the above upper limit, side reactions that cause coloring tend to be more suppressed. be.

After the isocyanurate-forming reaction is completed, it is preferable to remove unreacted diisocyanate monomer by a thin film evaporator, extraction, or the like. Even if the polyisocyanate contains unreacted diisocyanate, the diisocyanate content is preferably 3.0% by mass or less, more preferably 1.0% by mass or less, based on the total mass of the polyisocyanate. , more preferably 0.5% by mass or less. When the concentration of residual unreacted diisocyanate monomer is within the above range, curability tends to be better.

(Method for producing polyisocyanate containing sulfonic acid anion group in the molecule)
A polyisocyanate containing a sulfonic acid anion group in the molecule can be obtained by reacting a sulfonic acid having a hydroxyl group or an amine salt thereof with the above diisocyanate or the above polyisocyanate.

(Sulfonic acid with hydroxyl group)
Examples of the sulfonic acid having a hydroxyl group include a compound represented by the following general formula (2) (hereinafter abbreviated as "sulfonic acid (2)").

In the formula (2), R ²¹ is a hydrocarbon group having 1 to 10 carbon atoms that may include at least one selected from the group consisting of a hydroxyl group, an ether bond, an ester bond, a carbonyl group, and an imino group. . R ²¹ may include a ring structure. The ring structure is an aromatic ring, a 5- or 6-membered ring containing two nitrogen atoms, or a 5- or 6-membered ring containing a nitrogen atom and an oxygen atom.

・^R21
In general formula (2), R ²¹ is a hydroxyl group, an ester bond (-COO-), an ether bond (-O-), a carbonyl group (-C(=O)-), an imino group (-NR-), and It is a hydrocarbon group having 1 or more and 10 or less carbon atoms which may include at least one member selected from the group consisting of ring structures.

The hydrocarbon group having 1 to 10 carbon atoms may be a divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 10 carbon atoms. There may be. The divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a chain alkylene group having 1 to 6 carbon atoms. In the case of a chain alkylene group having 1 to 6 carbon atoms, a part of the chain alkylene group may include a ring structure. The alkylene group having 1 or more and 6 or less carbon atoms may be linear or branched.

Among them, ^R21 is a chain alkylene group having 1 or more carbon atoms and 6 or less carbon atoms, a divalent aromatic hydrocarbon group (arylene group) having 6 or more carbon atoms and 10 or less carbon atoms, and a divalent carbon number 1 or more containing an aromatic ring. An alkylene group having 10 or less, a divalent alkylene group having 1 or more and 6 or less carbon atoms, including a 5-membered ring or 6-membered ring containing 2 nitrogen atoms, or a 5- or 6-membered ring containing a nitrogen atom and an oxygen atom. It is preferably a divalent alkylene group containing a ring and having 1 or more and 6 or less carbon atoms.

Preferred sulfonic acids (2) include, for example, 2-hydroxyethanesulfonic acid, 3-hydroxypropanesulfonic acid, 4-hydroxybutanesulfonic acid, 5-hydroxypentanesulfonic acid, 6-hydroxyhexanesulfonic acid, and hydroxybenzene. Sulfonic acid, hydroxy(methyl)benzenesulfonic acid, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid, 2-hydroxy-3-morpholino Examples include propanesulfonic acid.
Note that these compounds are only some of the preferred sulfonic acids (2), and the preferred sulfonic acids (3) are not limited thereto.
Further, these sulfonic acids (2) may be used alone or in combination of two or more.

Among them, the sulfonic acid having a hydroxyl group is at least one selected from the group consisting of 2-hydroxyethanesulfonic acid, 3-hydroxypropanesulfonic acid, hydroxybenzenesulfonic acid, and hydroxy(methyl)benzenesulfonic acid. is preferred.

In addition, when the polyisocyanate composition of this embodiment contains two or more types of amine salts of sulfonic acids, the sulfonic acids (2) may be the same or different.

Further, the sulfonic acid used in the polyisocyanate containing a sulfonic acid anion group in the molecule preferably forms a salt with the amine compound (1).

<Tertiary ammonium cation of amine compound>
The polyisocyanate composition of this embodiment contains the tertiary ammonium cation of the amine compound (1). The polyisocyanate composition of this embodiment may contain one type of amine compound (1) alone, or may contain two or more types in combination.

(In general formula (1), R ¹¹ , R ¹² and R ¹³ are each independently a hydrocarbon group having 1 to 10 carbon atoms and which may contain an ether bond. ^{R 11} , R ¹² and R ¹³ At least one selected from the group consisting of may include a ring structure, and two or more selected from the group consisting of R ¹¹ , R ¹² and R ¹³ may be bonded to each other to form a ring structure. The structure is an aromatic ring, a cycloalkyl group having 5 or 6 carbon atoms, a 5- or 6-membered ring in which R ¹¹ and R ¹² are bonded to each other, or a structure in which R ¹¹ , R ¹² , and R ¹³ are bonded to each other. It is a multi-membered ring.)

Moreover, in the polyisocyanate composition of this embodiment, it is preferable that the amine compound (1) forms a salt with the above-mentioned sulfonic acid.

[Amine compound (1)]
(R ¹¹ , R ¹² and R ¹³ )
In general formula (1), R ¹¹ , R ¹² and R ¹³ are each independently a hydrocarbon group having 1 to 10 carbon atoms and which may contain an ether bond. R ¹¹ , R ¹² and R ¹³ may be the same or different.

The hydrocarbon group having 1 to 10 carbon atoms may be a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 carbon atoms. good. The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a chain alkyl group having 1 to 10 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms. The chain alkyl group having 1 to 10 carbon atoms may be linear or branched.

Preferred amine compounds (1) include, for example, N,N-dimethylethylamine, N,N-dimethylpropylamine, N,N-dimethylisopropylamine, N,N-dimethylbutylamine, N,N-dimethylisobutylamine, , N-dimethyloctylamine, N,N-dimethyl-2-ethylhexylamine, N,N-dimethyllaurylamine, N,N-diethylmethylamine, N,N-diethylbutylamine, N,N-diethylhexylamine, N , N-diethyloctylamine, N,N-diethyl-2-ethylhexylamine, N,N-diethyllaurylamine, N,N-diisopropylmethylamine, N,N-diisopropylethylamine, N,N-diisopropylbutylamine, N, N-diisopropyl-2-ethylhexylamine, N-methyl-dioctylamine, N,N-dimethylallylamine, N-methyldiallylamine, tripropylamine, tripropylamine, tributylamine, N,N-diethylpropylamine, N,N -dibutylpropylamine, N,N-dipropyloctylamine, N,N-dimethylbenzylamine, N,N-diethylbenzylamine, N,N-dibenzylmethylamine, tribenzylamine, N,N-dimethyl-4 -Methylbenzylamine, N,N-dimethylcyclohexylamine, N,N-diethylcyclohexylamine, N,N-dicyclohexylmethylamine, N,N-dicyclohexylethylamine, tricyclohexylamine, N-methylpyrrolidine, N-ethylpyrrolidine, N-propylpyrrolidine, N-butylpyrrolidine, N-methylpiperidine, N-ethylpiperidine, N-propylpiperidine, N-butylpiperidine, N-methylmorpholine, N-ethylmorpholine, N-propylmorpholine, N-butylmorpholine, Examples include N-sec-butylmorpholine, N-tert-butylmorpholine, N-isobutylmorpholine, and quinuclidine. Note that these compounds are only some of the preferred amine compounds (1), and the preferred amine compounds (1) are not limited to these. Moreover, one type of these amine compounds (1) may be used, or two or more types may be used in combination.

Among them, N,N-dimethylpropylamine, N,N-dimethylbutylamine, N,N-dimethyl-2-ethylhexylamine, N,N-diethylmethylamine, N,N-diisopropylethylamine, N,N-diisopropyl-2 -Ethylhexylamine, N,N-dimethylallylamine, tripropylamine, tributylamine, N,N-diethylpropylamine, N,N-dibutylpropylamine, N,N-dipropyloctylamine, N,N-dimethylcyclohexylamine , N,N-dicyclohexylmethylamine, N-methylpyrrolidine, N-methylpiperidine, N-ethylpiperidine, N-methylmorpholine, N-ethylmorpholine or N-isobutylmorpholine are preferred.

Also, N,N-dimethylpropylamine, N,N-dimethylbutylamine, N,N-diethylmethylamine, N,N-diisopropylethylamine, tripropylamine, tributylamine, N,N-dipropyloctylamine, Particular preference is given to N-dimethylcyclohexylamine or N-methylpiperidine.

[Other amine compounds]
The polyisocyanate composition of this embodiment may contain tertiary ammonium cations of other amine compounds in addition to the tertiary ammonium cations of the amine compound (1).
Other amine compounds may be other than the above amine compound (1) and are not particularly limited. Specific examples of other amine compounds include those shown in (a) to (b) below. Moreover, one type of these other amine compounds may be used, or two or more types may be used in combination.
(a) Trimethylamine, N,N-dimethylpentylamine, N,N-dimethylhexylamine, N,N-diethylisopropylamine, N,N-diethylisobutylamine, N,N-dimethylheptylamine, N,N-dimethyl Nonylamine, N,N-dimethyldecylamine, N,N-dimethylundecylamine, N,N-dimethyldodecylamine, N,N-dimethyltridecylamine, N,N-dimethylstearylamine, N,N-diethyl Pentylamine, N,N-diethylheptylamine, N,N-diethylnonylamine, N,N-diethyldecylamine, N,N-diethylundecylamine, N,N-diethyldodecylamine, N,N-diethyltri Decylamine, N,N-diethylstearylamine, N,N-dibutylmethylamine, N,N-dibutylethylamine, N,N-dibutylpentylamine, N,N-dibutylhexylamine, N,N-dibutylheptylamine, N,N-dibutyloctylamine, N,N-dibutyl-2-ethylhexylamine, N,N-dibutylnonylamine, N,N-dibutyldecylamine, N,N-dibutylundecylamine, N,N-dibutyldodecyl Tertiary amines having a chain aliphatic hydrocarbon group such as amine, N,N-dibutyltridecylamine, N,N-dibutylstearylamine, triamylamine, trihexylamine;
(b) Tertiary amines having an aromatic hydrocarbon group such as N,N-dimethylphenylamine, N,N-diethylphenylamine, and N,N-diphenylmethylamine.

<Method for producing amine salt of sulfonic acid>
When the sulfonic acid forms a salt with the amine compound, that is, when it is an amine salt of sulfonic acid, it can be obtained by, for example, mixing a sulfonic acid having a hydroxyl group with an amine compound and causing a neutralization reaction. .

The neutralization reaction may be performed in advance before reacting with the polyisocyanate. Alternatively, the reaction may be performed simultaneously with the polyisocyanate. Alternatively, the amine compound may be added after the polyisocyanate and the sulfonic acid having a hydroxyl group are reacted.

The neutralization reaction is preferably carried out in advance before reacting with the polyisocyanate.
In the neutralization reaction, the ratio of mixing the sulfonic acid having a hydroxyl group and the amine compound is preferably such that the molar ratio of the sulfonic acid having a hydroxyl group/amine compound is 0.8 or more and 0.99 or less, and 0.85 More preferably, it is 0.99 or less.

When the neutralization reaction is carried out in advance, the temperature and time can be determined as appropriate depending on the progress of the reaction, but the temperature is usually preferably about 0°C or more and 100°C or less, and the mixing time is 10 minutes or more. It is preferably about 24 hours or less.

The solvent used in the preparation of the hydroxyl group-containing sulfonic acid amine salt is preferably water or a hydrophilic solvent. Examples of the hydrophilic solvent include, but are not limited to, alcohols, ether alcohols, ketones, amide solvents, and the like. These solvents can be used alone or in combination.
Examples of alcohols include methanol, ethanol, propanol, butanol, isopropanol, and the like.
Examples of ether alcohols include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, etc. can be mentioned.
Examples of ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, and the like.
Examples of the amide solvent include N,N-dimethylformamide and N,N-dimethylacetamide.

After the neutralization reaction, it is preferable to remove water or the hydrophilic solvent.

<Characteristics of polyisocyanate composition>
From the viewpoint of emulsifying properties and physical properties of the coating film, the polyisocyanate composition of the present embodiment has a sulfonic acid having a hydroxyl group in an amount of 0.25 to 50 mol based on 100 mol of isocyanate groups of the raw material polyisocyanate. It is preferable that the isocyanate groups are modified in a ratio of 0.5 molar or more and 20 molar or less, and more preferably that the isocyanate groups are modified in a ratio of 1 molar or more and 10 molar or less. More preferably, the isocyanate group is modified.

In addition, the isocyanate group content of the polyisocyanate composition of the present embodiment is preferably 10% by mass or more and 25% by mass or less from the viewpoint of solvent resistance of the coating film, when the nonvolatile content is 100% by mass. The content is preferably 15% by mass or more and 24% by mass or less. The method for controlling the isocyanate group content within the above range is not particularly limited, but includes, for example, a method of adjusting the blending ratio of sulfonic acid and polyisocyanate.

In addition, the number average molecular weight of the polyisocyanate (including polyisocyanate containing a sulfonic acid anion group in the molecule and unreacted polyisocyanate) used in the polyisocyanate composition of this embodiment is determined from the viewpoint of solvent resistance of the coating film. Therefore, it is preferably 450 or more and 2,000 or less, more preferably 500 or more and 1,800 or less, and even more preferably 550 or more and 1,550 or less. The method for controlling the number average molecular weight within the above range is not particularly limited, but includes, for example, a method of adjusting the blending ratio of sulfonic acid, amine compound, and polyisocyanate.
The number average molecular weight can be measured using, for example, gel permeation chromatography (GPC).

In addition, the average number of functional groups of the polyisocyanate (including modified polyisocyanate and unreacted polyisocyanate) used in the polyisocyanate composition of this embodiment is determined from the viewpoint of solvent resistance of the coating film and isocyanate group retention rate. , is preferably 1.8 or more and 6.2 or less, more preferably 2.0 or more and 5.6 or less, and even more preferably 2.5 or more and 4.6 or less. The method for controlling the average number of functional groups within the above range is not particularly limited, but includes, for example, a method of adjusting the blending ratio of sulfonic acid, amine compound, and polyisocyanate.

In addition, in this embodiment, the isocyanate group content, nonvolatile content, and average number of functional groups can be measured by the method described in Examples below.

<Other ingredients>
The polyisocyanate composition of this embodiment is a composition containing a polyisocyanate containing the above-mentioned sulfonic acid anion group in the molecule, unreacted polyisocyanate, and the tertiary ammonium cation of the amine compound (1). The polyisocyanate composition of the present embodiment contains other components in addition to the above-mentioned polyisocyanate containing a sulfonic acid anion group in the molecule, unreacted polyisocyanate, and the tertiary ammonium cation of the amine compound (1). Good too. Other components include, but are not particularly limited to, solvents, antioxidants, light stabilizers, polymerization inhibitors, surfactants, and the like.

The solvent used in the polyisocyanate composition of this embodiment may be a hydrophilic solvent or a hydrophobic solvent. These solvents can be used alone or in combination.

Examples of hydrophobic solvents include, but are not limited to, mineral spirits, solvent naphtha, LAWS (Low Aromatic White Spirit), HAWS (High Aromatic White Spirit), toluene, xylene, cyclohexane, esters, ketones, and amides. Can be mentioned.
Examples of esters include ethyl acetate and butyl acetate.
Examples of ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.
Examples of amides include N,N-dimethylformamide and N,N-dimethylacetamide.

Examples of the hydrophilic solvent include, but are not limited to, alcohols, ethers, and esters of ether alcohols.
Examples of alcohols include methanol, ethanol, propanol, isopropanol, and 2-ethylhexanol.
Examples of the ethers include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, and dipropylene glycol dimethyl ether.
Examples of esters of ether alcohols include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol. Examples include monomethyl ether acetate and dipropylene glycol monomethyl ether acetate.

In the polyisocyanate composition of this embodiment, the content of the solvent is preferably 0% by mass or more and 90% by mass or less, and 0% by mass or more and 50% by mass or less, based on the total mass of the polyisocyanate composition of this embodiment. It is more preferably not more than 0% by mass, and even more preferably not less than 0% by mass and not more than 30% by mass.

Examples of the antioxidant and light stabilizer include those shown in (a) to (e) below. These may be contained alone or in combination of two or more kinds.
(a) Aliphatic, aromatic or alkyl group-substituted aromatic esters of phosphoric acid or phosphorous acid and hypophosphorous acid derivatives;
(b) Phosphorus compounds such as phenylphosphonic acid, phenylphosphinic acid, diphenylphosphonic acid, polyphosphonate, dialkylpentaerythritol diphosphite, dialkylbisphenol A diphosphite;
(c) phenolic derivatives (especially hindered phenol compounds);
(d) Compounds containing sulfur such as thioether compounds, dithioate salt compounds, mercaptobenzimidazole compounds, thiocarbanilide compounds, thiodipropionic acid esters;
(e) Tin-based compounds such as tin malate and dibutyltin monoxide

Examples of the polymerization inhibitor include hydroquinones, phenols, cresols, catechols, and benzoquinones. Specific examples of the polymerization inhibitor include benzoquinone, p-benzoquinone, p-torquinone, p-xyloquinone, naphthoquinone, 2,6-dichloroquinone, hydroquinone, trimethylhydroquinone, catechol, pt-butylcatechol, 2, Examples include 5-di-t-butylhydroquinone, monomethylhydroquinone, p-methoxyphenol, 2,6-di-t-butyl-p-cresol, and hydroquinone monomethyl ether. These may be contained alone or in combination of two or more kinds.

Examples of the surfactant include known anionic surfactants, cationic surfactants, and amphoteric surfactants.

In the polyisocyanate composition of this embodiment, the total content of the antioxidant, light stabilizer, polymerization inhibitor, and surfactant is 0% by mass or more with respect to the total mass of the polyisocyanate composition of this embodiment. The content is preferably 10% by mass or less, more preferably 0% by mass or more and 5% by mass or less, and even more preferably 0% by mass or more and 2% by mass or less.

≪Method for producing polyisocyanate composition≫
The method for producing the polyisocyanate composition of the present embodiment preferably includes, for example, a step of mixing and reacting (A) an amine salt of a sulfonic acid having a hydroxyl group with a polyisocyanate.

Alternatively, the method for producing a polyisocyanate composition of the present embodiment preferably includes, for example, a step of mixing and reacting (B) a sulfonic acid having a hydroxyl group, a polyisocyanate, and the amine compound (1).

In step (A), the amine salt of sulfonic acid is preferably prepared in advance and then added to the polyisocyanate. In step (A), when preparing the amine salt of sulfonic acid according to the above-mentioned "method for producing amine salt of sulfonic acid", by changing the blending ratio of the sulfonic acid having a hydroxyl group and the amine compound, the sulfonic acid The molar ratio of anion group/tertiary ammonium cation can be adjusted to 0.8 or more and 0.99 or less.

Moreover, in step (B), the sulfonic acid having a hydroxyl group and the amine compound may be added to the polyisocyanate simultaneously or sequentially. In step (B), by changing the blending ratio of the sulfonic acid having a hydroxyl group and the amine compound, the molar ratio of sulfonic acid anion group/tertiary ammonium cation can be adjusted to 0.8 or more and 0.99 or less. can.

Among these, step (A) is preferable, and it is more preferable that the sulfonic acid amine salt is prepared in advance and then added to the polyisocyanate.

In the reaction step, the mixing ratio of the sulfonic acid having a hydroxyl group or its amine salt and the polyisocyanate is in the range of 2 to 400 in molar ratio of isocyanate group/hydroxyl group from the viewpoint of emulsifying property and physical properties of the coating film. It is preferably in the range of 5 or more and 200 or less, and even more preferably in the range of 10 or more and 100 or less.

In the reaction step, the reaction temperature and reaction time are appropriately determined depending on the progress of the reaction, but the reaction temperature is preferably 0°C or more and 150°C or less, and the reaction time is 30 minutes or more and 48 hours or less. is preferred.

Further, in the reaction step, a known common catalyst may be used depending on the case. The catalyst is not particularly limited, but includes, for example, those shown in (a) to (f) below. These may be used alone or in combination.
(a) Tin octoate, tin 2-ethyl-1-hexanoate, tin ethyl caproate, tin laurate, tin palmitate, dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dimalate, dibutyltin dilaurate, dioctyltin dichloride Organotin compounds such as acetate and dioctyltin dilaurate;
(b) organic zinc compounds such as zinc chloride, zinc octoate, zinc 2-ethyl-1-hexanoate, zinc 2-ethylcaproate, zinc stearate, zinc naphthenate, zinc acetylacetonate;
(c) organic titanium compound;
(d) organic zirconium compound;
(e) Tertiary amines such as triethylamine, tributylamine, N,N-diisopropylethylamine, N,N-dimethylethanolamine;
(f) Diamines such as triethylenediamine, tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, etc.

In the method for producing a polyisocyanate composition of this embodiment, a solvent may or may not be used. The solvent used in the method for producing the polyisocyanate composition of this embodiment may be a hydrophilic solvent or a hydrophobic solvent. Examples of the hydrophilic solvent and hydrophobic solvent include those exemplified above for other components.

In addition, in the method for producing a polyisocyanate composition of the present embodiment, in addition to the sulfonic acid having a hydroxyl group, the polyisocyanate, and the amine compound, an antioxidant, a light stabilizer, a polymerization inhibitor, and a surfactant are further added. At least one member selected from the group consisting of: As the antioxidant, light stabilizer, polymerization inhibitor, and surfactant, the same ones as those exemplified for the other components mentioned above can be mentioned.

≪Coating composition≫
The coating composition of this embodiment includes the above-mentioned polyisocyanate composition.
The coating composition of this embodiment can also be used as an organic solvent-based coating composition, but it may also be used as an aqueous coating composition in which resins as coating film-forming components are dissolved or dispersed in a medium mainly composed of water. It is preferable to use it as In particular, architectural paints, automotive paints, automotive refinish paints, plastic paints, pressure-sensitive adhesives, building materials, household water-based paints, other coating agents, sealants, inks, casting materials, elastomers, foams, and plastic raw materials. , it can also be used as a fiber treatment agent.

<Resins>
The main resins are not particularly limited, but examples include acrylic resins, polyester resins, polyether resins, epoxy resins, fluororesins, polyurethane resins, polyvinylidene chloride copolymers, polyvinyl chloride, etc. Polymers, vinyl acetate copolymers, acrylonitrile butadiene copolymers, polybutadiene copolymers, styrene butadiene copolymers, and the like.
Among these, acrylic resins or polyester resins are preferred as the resins.

(Acrylic resin)
Acrylic resins are not particularly limited, but include, for example, acrylic resins obtained by polymerizing single or mixtures of polymerizable monomers shown in (a) to (e) below. These acrylic resins may be used alone or in combination.
(a) Methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate (meth)acrylic acid esters such as;
(b) 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, (meth) (meth)acrylic acid esters with active hydrogen such as 4-hydroxybutyl acrylate;
(c) unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid;
(d) Unsaturated amides such as acrylamide, N-methylolacrylamide, diacetone acrylamide;
(e) Other polymerizable monomers such as glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, dibutyl fumarate, p-styrenesulfonic acid, allylsulfosuccinic acid, etc.

As a polymerization method, emulsion polymerization is generally used, but it can also be produced by suspension polymerization, dispersion polymerization, and solution polymerization. Emulsion polymerization can also be carried out in stages.

(Polyester resins)
Examples of polyester resins include, but are not limited to, polyester resins obtained by a condensation reaction of carboxylic acids alone or in mixtures with polyhydric alcohols alone or in mixtures.
Examples of the carboxylic acid include succinic acid, adipic acid, sebacic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid.
Examples of the polyhydric alcohol include diols, triols, and tetraols.
Examples of diols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3- Butanediol, 1,4-butanediol, 2,3-butanediol, 2-methyl-1,2-propanediol, 1,5-pentanediol, 2-methyl-2,3-butanediol, 1,6- Hexanediol, 1,2-hexanediol, 2,5-hexanediol, 2-methyl-2,4-pentanediol, 2,3-dimethyl-2,3-butanediol, 2-ethyl-hexanediol, 1, 2-octanediol, 1,2-decanediol, 2,2,4-trimethylpentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, etc. can be mentioned.
Examples of triols include glycerin, trimethylolpropane, and the like.
Examples of the tetraols include diglycerin, dimethylolpropane, and pentaerythritol.

Alternatively, for example, polycaprolactones obtained by ring-opening polymerization of ε-caprolactone to the hydroxyl group of a low molecular weight polyol can also be used as the polyester resin.

(Polyether resins)
Examples of polyether resins include those shown in (a) to (d) below.
(a) Polyether polyols obtained by adding alkylene oxide alone or as a mixture to a polyhydric hydroxy compound alone or as a mixture using a strong basic catalyst;
(b) polyether polyols obtained by reacting a polyamine compound with an alkylene oxide;
(c) polyether polyols obtained by ring-opening polymerization of cyclic ethers;
(d) So-called polymer polyols obtained by polymerizing acrylamide etc. using the polyether polyols obtained in (a) to (c) as a medium.

Examples of the polyvalent hydroxy compound in (a) include those shown in (i) to (vi) below.
(i) diglycerin, ditrimethylolpropane, pentaerythritol, dipentaerythritol, etc.;
(ii) Sugar alcohol compounds such as erythritol, D-threitol, L-arabinitol, ribitol, xylitol, sorbitol, mannitol, galactitol, rhamnitol;
(iii) monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbose, rhamnose, fucose, ribodesose;
(iv) Disaccharides such as trehalose, sucrose, maltose, cellobiose, gentiobiose, lactose, melibiose;
(v) trisaccharides such as raffinose, gentianose, meletitose;
(vi) Tetrasaccharides such as stachyose

Examples of the strong basic catalyst in (a) include alkali metal hydroxides, alcoholates, and alkylamines. Examples of the alkali metals include lithium, sodium, potassium, and the like.

Examples of the alkylene oxide in (a) include ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, and styrene oxide.

Examples of the polyamine compound in (b) include ethylenediamines.

Examples of the cyclic ethers in (c) include tetrahydrofuran.

Furthermore, in the coating composition of the present embodiment, these resins may be used in combination with resins such as a melamine curing agent, urethane dispersion, and urethane acrylic emulsion, if necessary.

Moreover, these resins are preferably emulsified, dispersed, or dissolved in water. For this purpose, carboxyl groups, sulfone groups, etc. contained in resins can be neutralized.
Examples of the neutralizing agent for neutralizing carboxyl groups, sulfone groups, etc. include, but are not limited to, ammonia, water-soluble amino compounds, and the like.
Examples of water-soluble amino compounds include monoethanolamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, dipropylamine, isopropylamine, diisopropylamine, triethanolamine, butylamine, dibutylamine, 2-ethylhexylamine, and ethylenediamine. , propylene diamine, methylethanolamine, dimethylethanolamine, diethylethanolamine, morpholine and the like. These may be used alone or in combination of two or more.
Among these, the neutralizing agent is preferably a tertiary amine, more preferably triethylamine or dimethylethanolamine.

<Other ingredients>
In addition to the polyisocyanate composition and resins described above, the coating composition of the present embodiment may further contain additives that are generally added to paints. Examples of such additives include inorganic pigments, organic pigments, extender pigments, silane coupling agents, titanium coupling agents, organic phosphates, organic phosphites, thickeners, leveling agents, thixoating agents, and extinguishers. Foaming agents, freeze stabilizers, matting agents, crosslinking reaction catalysts (catalysts for accelerating hardening), antiskinning agents, dispersants, wetting agents, fillers, plasticizers, lubricants, reducing agents, preservatives, anti-mold agents agents, deodorants, anti-yellowing agents, ultraviolet absorbers, antistatic agents or charge control agents, anti-settling agents and the like. These additives may be contained alone or in combination of two or more.

Examples of the crosslinking reaction catalyst (catalyst for accelerating curing) include, but are not limited to, those shown in (a) or (b) below.
(a) Metal salts such as dibutyltin dilaurate, tin 2-ethylhexanoate, zinc 2-ethylhexanoate, cobalt salts;
(b) 3 such as triethylamine, pyridine, methylpyridine, benzyldimethylamine, N,N-dimethylcyclohexylamine, N-methylpiperidine, pentamethyldiethylenetriamine, N,N'-endoethylenepiperazine, N,N'-dimethylpiperazine, etc. class amines

The coating composition of this embodiment may further contain a surfactant in addition to the above-mentioned polyisocyanate composition and resins in order to improve dispersibility in the paint.

The coating composition of this embodiment may further contain an antioxidant, a light stabilizer, and a polymerization inhibitor in addition to the polyisocyanate composition and resins described above, in order to improve the storage stability of the paint.

≪Coating base material≫
The coated base material of this embodiment is a coated base material coated with the above-mentioned coating composition. The coated base material of this embodiment preferably has a coating layer containing the above-mentioned coating composition.

The coated substrate of this embodiment may include the desired substrate and optionally a conventional primer before coating.
Examples of the substrate include metal, wood, glass, stone, ceramic materials, concrete, hard and flexible plastics, textile products, leather products, paper, and the like.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof.
The physical properties and evaluation of the polyisocyanate compositions in Examples and Comparative Examples were measured as follows. Note that unless otherwise specified, "parts" and "%" mean "parts by mass" and "% by mass."

<Measurement method>
[Physical Properties 1] Viscosity Viscosity was measured at 25°C using an E-type viscometer (manufactured by Tokimec Co., Ltd.). A standard rotor (1°34' x R24) was used. The rotation speed is as follows.

(number of rotations)
100r. p. m. (If less than 128mPa・s)
50r. p. m. (In the case of 128 mPa・s or more and less than 256 mPa・s)
20r. p. m. (In case of 256 mPa・s or more and less than 640 mPa・s)
10r. p. m. (In case of 640mPa・s or more and less than 1280mPa・s)
5r. p. m. (In case of 1280mPa・s or more and less than 2560mPa・s)
2.5r. p. m. (In case of 2560mPa・s or more and less than 5120mPa・s)

[Physical properties 2] Isocyanate group content The isocyanate group content was measured using the polyisocyanate compositions obtained in Examples and Comparative Examples as samples according to JIS K7301-1995 (Tolylene diisocyanate type prepolymer for thermosetting urethane elastomers). The test was carried out according to the method described in (Test Method). A more specific method for measuring the isocyanate group content is shown below.

(1) 1 g (Wg) of the sample was collected in a 200 mL Erlenmeyer flask, and 20 mL of toluene was added to the flask to dissolve the sample.
(2) Thereafter, 20 mL of a 2.0N di-n-butylamine toluene solution was added to the flask, and the flask was left standing for 15 minutes.
(3) 70 mL of 2-propanol was added to the flask and dissolved to obtain a solution.
(4) The solution obtained in (3) above was titrated using 1 mol/L hydrochloric acid to determine the sample titer (V1 mL).
(5) Even when no sample was added, measurements were performed in the same manner as in (1) to (3) above to determine the blank titer (V0 mL).
From the sample titer and blank titer determined above, the isocyanate group content (NCO%) was calculated using the formula shown below.

Isocyanate group content (mass%) = (V0-V1)×42/[W(1g)×1000]×100

[Physical Property 3] Nonvolatile Content When the polyisocyanate compositions obtained in Examples and Comparative Examples were diluted with a solvent, the nonvolatile content was calculated using the method shown below. First, the mass of an aluminum cup was accurately weighed (W0 g), about 1 g of a sample was put therein, and the mass of the cup before heating and drying (W1 g) was accurately weighed. The cup containing the sample was then heated in a dryer at 105° C. for 3 hours. Next, after cooling the cup after heating to room temperature, the mass of the cup was accurately weighed again (W2 g). Next, the nonvolatile content was calculated using the formula shown below, using the mass % of the dry residue in the sample as the nonvolatile content. In addition, in the case of no solvent dilution, the nonvolatile content was treated as being substantially 100%.

Non-volatile content (mass%) = (W2-W0)/(W1-W0)×100

[Physical property 4] Number average molecular weight (Mn)
The number average molecular weight of the polyisocyanate composition was obtained by measuring the number average molecular weight based on polystyrene by GPC measurement under the measurement conditions shown below.

(Measurement condition)
Equipment: Tosoh Corporation HLC-8120GPC (product name)
Column: Tosoh Corporation TSKgel SuperH1000 (product name) x 1 TSKgel SuperH2000 (product name) x 1 TSKgel SuperH3000 (product name) x 1 Carrier: Tetrahydrofuran Detection method: Differential refractometer

[Physical property 5] Average number of functional groups The average number of functional groups is the number of isocyanate functional groups that one molecule of polyisocyanate statistically has, and is the number average molecular weight (Mn) of the polyisocyanate obtained in "Physical property 4" and "Physical property 2". It was calculated using the following formula from the isocyanate group content (NCO%) obtained in ``.

Average number of functional groups = Mn×NCO%/4200

[Physical property 6] Molar ratio of sulfonic acid anion group to tertiary ammonium cation Based on the results of LC-MS and UV-MS measurements using WATERS's "UPLC", the molar ratio of sulfonic acid anion group/tertiary ammonium cation The molar ratio of cations was calculated from each peak area.

<Evaluation method>
[Evaluation 1] Water dispersibility of polyisocyanate composition Using the polyisocyanate compositions obtained in Examples and Comparative Examples as samples, water dispersibility was evaluated using the method shown below.
(1) The mass of the 100 mL flask and Yoshino paper was measured (W0 g).
(2) The polyisocyanate composition was collected in a 100 mL flask so as to have a solid content of 16 g (W2 g), and 24 g of deionized water was added.
(3) Using a propeller blade, the solution in the 100 mL flask was stirred at 200 rpm for 3 minutes, and then filtered through the Yoshino paper weighed in (1).
(4) The filtration residue remaining on the Yoshino paper and the residue remaining in the 100 mL flask were combined and heated in a dryer at 105°C for 1 hour, and the mass (g) was determined (W1g).
(5) The proportion of the polyisocyanate composition dispersed in water was determined using the following formula. In addition, in formula (D), Y is a nonvolatile content (mass %).

Percentage dispersed in water (mass%) = {1-(W2(g)-W0(g))/(W2(16g)×Y)}×100

(6) Next, water dispersibility was evaluated according to the following evaluation criteria.

(Evaluation criteria)
◎: 95% by mass or more ○: 90% by mass or more and less than 95% by mass △: 80% by mass or more and less than 90% by mass ×: Less than 80% by mass

[Manufacture of coating composition]
Acrylic polyol water dispersion (product name: Setaqua 6510, hydroxyl value per resin: 138 mgKOH/g, manufactured by Allnex): 40 g was weighed into a container. Next, the ratio (NCO/OH) of the molar amount of isocyanate groups in the polyisocyanate compositions obtained in Examples and Comparative Examples to the molar amount of hydroxyl groups in the aqueous acrylic polyol dispersion was 1.25. , each polyisocyanate composition was added. Further, deionized water was added so that the solid content in the coating composition was 42% by mass, and the mixture was stirred for 10 minutes at 600 rpm using a propeller blade to obtain each coating composition. The following evaluation was performed using the produced coating composition.

[Evaluation 2] Pot life Using each coating composition obtained by the above method, a coating film with a thickness of 40 μm was coated on a glass plate every hour until gelation, and the coating composition was heated at 23°C and 50% humidity. It was dried in an atmosphere, and the gloss of the resulting coating film was measured the next day. The time immediately after the preparation of the coating composition is taken as 0 hours, the glossiness (20°) of the coating film at that time is taken as G0, the glossiness after n hours is taken as Gn, and the retention rate of isocyanate groups = Gn/G0 is calculated, 80 % or more was defined as the pot life time. Pot life was evaluated according to the following evaluation criteria.

(Evaluation criteria)
○: 4 hours or more △: 2 hours or more and less than 4 hours ×: less than 2 hours

[Evaluation 3] Appearance of coating film A coating film with a thickness of 40 μm was coated on a glass plate using each coating composition obtained by the above method. Next, it was dried in an atmosphere of 23°C and 50% humidity, and the next day, the gloss value of the obtained coating film was measured using a gloss meter (digital variable angle gloss meter UDV-6P (product name) manufactured by Suga Test Instruments Co., Ltd.). The 60 degree gloss value was measured under the conditions of JIS Z8741. The appearance was evaluated according to the following evaluation criteria.

(Evaluation criteria)
○: 85% or more △: Less than 85% 65% or more ×: Less than 65%

<Synthesis of sulfonic acid amine salt>
[Synthesis Example 1] Synthesis of HES/4-picoline To 20 parts by mass of a 70% by mass aqueous solution of 2-hydroxyethanesulfonic acid (hereinafter sometimes abbreviated as "HES"), 10 parts by mass of 1-propanol was added. Add and stir to obtain a solution. Furthermore, 4-picoline was weighed out so that the molar equivalent ratio to HES was 1.10, and a solution diluted with the same mass part of 1-propanol was added dropwise to the stirring solution. One hour after the start of the dropwise addition, the stirring was stopped, and the mixture was dehydrated and desolvented using an evaporator, and the solid content was 99.8% by mass of 2-hydroxyethanesulfonic acid 4-picoline salt (hereinafter abbreviated as "HES/4-picoline"). ) was obtained.

[Synthesis Example 2] Synthesis of HBS/TBA To 20 parts by mass of an 85% by mass aqueous solution of 4-hydroxybenzenesulfonic acid (hereinafter sometimes abbreviated as "HBS"), 10 parts by mass of 1-propanol was added. A solution was obtained by stirring. Furthermore, tributylamine (hereinafter sometimes abbreviated as "TBA") was weighed out so that the molar equivalent ratio to HBS was 1.15, and the solution diluted with the same mass part of 1-propanol was added to the solution while stirring. It was added dropwise to the solution. One hour after the start of the dropwise addition, stirring was stopped, and the mixture was dehydrated and desolvented using an evaporator, and the solid content was 4-hydroxybenzenesulfonic acid tributylamine salt (hereinafter sometimes abbreviated as "HBS/TBA") with a solid content of 99.7% by mass. I got it.

[Synthesis Example 3] Synthesis of HPS/DIPEA 10 parts by mass of 1-propanol was added to 20 parts by mass of an 80% by mass aqueous solution of 3-hydroxypropanesulfonic acid (hereinafter sometimes abbreviated as "HPS"). A solution was obtained by stirring. Furthermore, N,N-diisopropylethylamine (hereinafter sometimes abbreviated as "DIPEA") was weighed out so that the molar equivalent ratio to HPS was 1.03, and the solution was diluted with the same mass part of 1-propanol. was added dropwise to the stirring solution. One hour after the start of the dropwise addition, stirring was stopped, water was removed and the solvent was removed using an evaporator, and 2-hydroxyethanesulfonic acid N,N-diisopropylethylamine salt (hereinafter abbreviated as "HPS/DIPEA") with a solid content of 99.5% by mass was obtained. ).

[Synthesis Example 4] Synthesis of HBS/TnPA Instead of tributylamine (TBA), tripropylamine (hereinafter sometimes abbreviated as "TnPA") was used so that the molar equivalent ratio to HBS was 1.22. 2-hydroxyethanesulfonic acid tripropylamine salt (hereinafter sometimes abbreviated as "HBS/TnPA") with a solid content of 99.6% by mass was obtained using the same method as in Synthesis Example 2, except that Ta.

[Synthesis Example 5] Synthesis of HPS/TBA 10 parts by mass of 1-propanol was added to 20 parts by mass of an 80% by mass aqueous solution of 3-hydroxypropanesulfonic acid (hereinafter sometimes abbreviated as "HPS"). A solution was obtained by stirring. Furthermore, tributylamine (hereinafter sometimes abbreviated as "TBA") was weighed out so that the molar equivalent ratio to HPS was 1.30, and the solution diluted with the same mass part of 1-propanol was added to the solution while stirring. It was added dropwise to the solution. One hour after the start of the dropwise addition, stirring was stopped, and the mixture was dehydrated and desolvented using an evaporator, and the solid content of 2-hydroxyethanesulfonic acid N,N-diisopropylethylamine salt (hereinafter abbreviated as "HPS/TBA") was 99.5% by mass. ).

[Synthesis Example 6] Synthesis of HES/TBA Except for using tributylamine (hereinafter sometimes abbreviated as "TBA") in place of 4-picoline so that the molar equivalent ratio to HES was 1.0. Using the same method as in Synthesis Example 1, 2-hydroxyethanesulfonic acid tributylamine salt (hereinafter sometimes abbreviated as "HES/TBA") with a solid content of 99.8% by mass was obtained.

<Synthesis of polyisocyanate>
[Synthesis Example 7] Synthesis of polyisocyanate P-1 A four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen blowing tube, and dropping funnel was made into a nitrogen atmosphere, and HDI: 1000 g and isobutanol: 4.0 g was charged, and the temperature inside the reactor was maintained at 70° C. while stirring. Tetramethylammonium capriate was added to this, and when the yield reached 25%, phosphoric acid was added to stop the reaction. Next, after filtering the reaction solution, unreacted HDI was removed using a thin film evaporator to obtain polyisocyanate P-1. The obtained polyisocyanate P-1 had a viscosity of 1500 mPa·s at 25°C and an isocyanate group content of 23.1%.

[Synthesis Example 8] Synthesis of Polyisocyanate P-2 Polyisocyanate P-2 was produced using the same method as Synthesis Example 8, except that phosphoric acid was added to stop the reaction when the yield reached 50%. I got it. The obtained polyisocyanate P-2 had a viscosity of 2700 mPa·s at 25° C. and an isocyanate group content of 21.7%.

<Manufacture of polyisocyanate composition>
[Example 1] Production of polyisocyanate composition PA-1a To 100 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 8, 2-hydroxyethanesulfonic acid 4-picoline salt obtained in Synthesis Example 1 ( HES/4-picoline): 6.1 parts by mass was added, and the reaction was carried out by stirring at 120° C. for 3 hours under nitrogen and reflux. Thereafter, the reflux was removed and the reaction was continued by stirring at 100° C. for 1 hour to obtain polyisocyanate composition PA-1a.

[Example 2] Production of polyisocyanate composition PA-2a Instead of polyisocyanate P-2 obtained in synthesis example 8, 100 parts by mass of polyisocyanate P-1 obtained in synthesis example 7 was added with synthesis example Example 1 except that 11.5 parts by mass of 4-hydroxybenzenesulfonic acid tributylamine salt (HBS/TBA) obtained in Synthesis Example 2 was added instead of HES/4-picoline obtained in Example 1. A similar method was used to produce polyisocyanate composition PA-2a.

[Example 3] Production of polyisocyanate composition PA-3a Instead of HES/4-picoline obtained in Synthesis Example 1, 2-hydroxyethanesulfonic acid N,N-diisopropylethylamine salt obtained in Synthesis Example 3 was used. (HPS/DIPEA): A polyisocyanate composition PA-3a was produced in the same manner as in Example 1 except that 8.6 parts by mass was added.

[Example 4] Production of polyisocyanate composition PA-4a Instead of HBS/TBA obtained in Synthesis Example 2, 2-hydroxyethanesulfonic acid tripropylamine salt (HBS/TnPA) obtained in Synthesis Example 4 was used. Polyisocyanate composition PA-4a was produced in the same manner as in Example 2, except that 8.4 parts by mass was added.

[Example 5] Production of polyisocyanate composition PA-5a 100 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 8 was added with 3-cyclohexylaminopropanesulfonic acid (hereinafter sometimes abbreviated as "CAPS"). ): 6.0 parts by mass (0.027 mol), and N,N-dimethylcyclohexylamine (hereinafter sometimes abbreviated as "DMCHA"): 3.7 parts by mass (0.029 mol). The mixture was added and stirred at 80° C. for 5 hours under reflux under a nitrogen atmosphere to produce polyisocyanate composition PA-8a.

[Comparative Example 1] Production of polyisocyanate composition PA-1b N,N-diisopropyl 2-hydroxyethanesulfonate obtained in Synthesis Example 5 was added to 100 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 8. Ethylamine salt (HPS/TBA): 10.3 parts by mass was added, and the reaction was carried out by stirring at 120° C. for 3 hours under reflux under nitrogen. Thereafter, the reflux was removed and the reaction was continued by stirring at 100° C. for 1 hour to obtain polyisocyanate composition PA-1b.

[Comparative Example 2] Production of polyisocyanate composition PA-2b To 100 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 8, 6.2 parts by mass (0.028 mol) of CAPS and DMCHA: 4.8 parts by mass (0.038 mol) was added and stirred at 80° C. for 5 hours under reflux under a nitrogen atmosphere to produce polyisocyanate composition PA-3b.

[Comparative Example 3] Production of polyisocyanate composition PA-3b 2-hydroxyethanesulfonic acid tributylamine salt (HES) obtained in Synthesis Example 6 was added to 100 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 7. /TBA): 8.4 parts by mass was added, and the reaction was carried out by stirring at 120° C. for 3 hours under nitrogen and reflux. Thereafter, the reflux was removed and the reaction was continued by stirring at 100° C. for 1 hour to produce polyisocyanate composition PA-3b.

The physical properties of the polyisocyanate compositions obtained in Examples and Comparative Examples were measured using the method described above. The results are shown in Table 1. Further, the obtained polyisocyanate composition was evaluated by the method described above. The results are shown in Table 1.

From Table 1, polyisocyanate compositions PA-1a to PA-5a (Examples 1 to 5) in which the molar ratio of sulfonic acid anion group/tertiary ammonium cation is 0.82 or more and 0.97 or less are It had excellent dispersibility and pot life when dispersed, and had a good appearance when formed into a coating.
Among the polyisocyanate compositions PA-1a to PA-5a (Examples 1 to 5), the polyisocyanate compositions PA-1a and PA- have a molar ratio of sulfonic acid anion group/tertiary ammonium cation of 0.91 or more. 3a and PA-5a (Examples 1, 3 and 5) had better pot life when dispersed in water and better appearance when formed into a coating.

On the other hand, in polyisocyanate compositions PA-1b and PA-2b (Comparative Examples 1 and 2) in which the molar ratio of sulfonic acid anion group/tertiary ammonium cation was 0.77 and 0.74, Although the dispersibility in this case was good, the pot life was poor and the appearance when formed into a coating film was poor. In addition, in the polyisocyanate composition PA-3b (Comparative Example 3) in which the molar ratio of sulfonic acid anion group/tertiary ammonium cation was 1, the pot life when dispersed in water and the appearance when formed into a coating film were Although the results were good, the dispersibility when dispersed in water was poor.

The polyisocyanate composition of the present embodiment can obtain excellent pot life and dispersibility when dispersed in water or a base agent containing water, and has excellent appearance when formed into a coating film.

Claims (6)

A polyisocyanate containing a sulfonic acid anion group in the molecule,
A polyisocyanate composition comprising a tertiary ammonium cation of an amine compound represented by the following general formula (1),
The molar ratio of the sulfonic acid anion group to the tertiary ammonium cation is 0.8 or more and 0.97 or less,
the polyisocyanate is an aliphatic polyisocyanate,
The tertiary ammonium cation of the amine compound represented by general formula (1) is selected from the group consisting of 4-picoline, tributylamine, N,N-diisopropylethylamine, N,N-dimethylcyclohexylamine, and tripropylamine. A coating film obtained by curing a coating composition comprising a polyisocyanate composition, which is a tertiary ammonium cation of at least one amine compound, and a base agent containing water .

(In general formula (1), R ¹¹ , R ¹² and R ¹³ are each independently a hydrocarbon group having 1 to 10 carbon atoms and which may contain an ether bond. ^{R 11} , R ¹² and R ¹³ At least one selected from the group consisting of may include a ring structure, and two or more selected from the group consisting of R ¹¹ , R ¹² and R ¹³ may be bonded to each other to form a ring structure. The structure is an aromatic ring, a cycloalkyl group having 5 or 6 carbon atoms, a 5- or 6-membered ring in which R ¹¹ and R ¹² are bonded to each other, or a structure in which R ¹¹ , R ¹² , and R ¹³ are bonded to each other. It is a multi-membered ring.) The coating film according to claim 1, wherein the molar ratio of the sulfonic acid anion group to the tertiary ammonium cation is 0.9 or more and 0.97 or less. The coating film according to claim 1 or 2, wherein the polyisocyanate has an isocyanurate group. The polyisocyanate containing a sulfonic acid anion group in the molecule is obtained by a reaction between an amine salt of a sulfonic acid having a hydroxyl group and a polyisocyanate,
The coating according to any one of claims 1 to 3, wherein the amine salt of a sulfonic acid having a hydroxyl group is a salt of a sulfonic acid having a hydroxyl group and an amine compound represented by the general formula (1). film . The coating film according to claim 4, wherein the sulfonic acid having a hydroxyl group is a compound represented by the following general formula (2).

(In general formula (2), R ²¹ is a hydrocarbon group having 1 to 10 carbon atoms that may contain at least one selected from the group consisting of a hydroxyl group, an ether bond, an ester bond, a carbonyl group, and an imino group. ^R21 may include a ring structure.The ring structure is an aromatic ring, a 5- or 6-membered ring containing two nitrogen atoms, or a 5- or 6-membered ring containing a nitrogen atom and an oxygen atom. It is a member ring.) A coated substrate coated with the coating composition and comprising a coating according to any one of claims 1 to 5 .