Polyisocyanate compositions, coating compositions and coating substrates

Abstract

A polyisocyanate composition, a coating composition, and a coating substrate are provided. The polyisocyanate composition provides excellent shelf life and dispersibility when dispersed in water or a water-containing main agent, and exhibits excellent appearance, water resistance, and hardness when formed into a coating film. The polyisocyanate composition comprises an ionic polyisocyanate compound (A) and a nonionic polyisocyanate compound (B), wherein the polyisocyanate compound is a compound derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates, and the mass ratio of the structural unit (a2) derived from the ionic compound to the structural unit (b2) derived from the nonionic compound is 50 / 50 or more and 98 / 2 or less.

Description

Technical Field

[0001] This invention relates to polyisocyanate compositions, coating compositions, and coating substrates. Background Technology

[0002] Coatings obtained from two-component polyurethane compositions using polyisocyanate compositions derived from aliphatic or alicyclic diisocyanates as curing agents exhibit excellent properties such as weather resistance, chemical resistance, and abrasion resistance. Therefore, they are widely used in coatings, inks, and adhesives. In recent years, with increasing attention paid to environmental issues, aqueous two-component polyurethane compositions that do not use organic solvents or reduce their usage have been proposed. However, compared to solvent-based two-component polyurethane compositions, aqueous two-component polyurethane compositions suffer from drawbacks such as poor dispersibility in water, easy reaction with water, and short shelf life. Therefore, there is a need for polyisocyanate compositions that exhibit high dispersibility in water and inhibit the reaction of isocyanate groups with water in the aqueous dispersion state.

[0003] For example, as methods for manufacturing aqueous two-component polyurethane compositions, Patent Documents 1 and 2 disclose water-dispersible polyisocyanate compounds and aqueous two-component polyurethane compositions obtained therefrom. Patent Documents 3 and 4 disclose a polyisocyanate composition comprising a modified polyisocyanate obtained by reacting an amine salt of a sulfonic acid having hydroxyl groups with a polyisocyanate.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 05-222150

[0007] Patent Document 2: Japanese Patent Application Publication No. 09-328654

[0008] Patent Document 3: Japanese Patent Application Publication No. 2015-205957

[0009] Patent Document 4: Japanese Patent Application Publication No. 2016-017157 Summary of the Invention

[0010] The problem the invention aims to solve

[0011] However, the compositions described in Patent Documents 1 and 2 are difficult to balance with excellent shelf life and dispersibility when dispersed in water or in an aqueous main agent. Patent Documents 3 and 4 disclose methods to improve dispersibility in water by using polyisocyanates containing sulfonic acid groups, but the sulfonic acid groups have poor compatibility with polyisocyanates, resulting in turbidity in the synthesized polyisocyanates.

[0012] The present invention is made in view of the above circumstances, and provides a polyisocyanate composition that can achieve excellent shelf life and dispersibility when dispersed in water or a water-containing main agent, and has excellent appearance, water resistance and hardness when formed into a coating film; as well as a coating composition and a coating substrate obtained using the aforementioned polyisocyanate composition.

[0013] Solution for solving the problem

[0014] That is, the present invention includes the following methods.

[0015] (1) A polyisocyanate composition comprising an ionic polyisocyanate compound (A) and a nonionic polyisocyanate compound (B),

[0016] The ionic polyisocyanate compound (A) is derived from the polyisocyanate compound (a1) and one or more ionic compounds selected from the group consisting of anionic and cationic compounds.

[0017] The nonionic polyisocyanate compound (B) is derived from the nonionic compound and the polyisocyanate compound (b1).

[0018] The aforementioned polyisocyanate compound (a1) and the aforementioned polyisocyanate compound (b1) are respectively polyisocyanate compounds derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates.

[0019] The mass ratio (a2) / (b2) of the structural unit (a2) derived from the ionic compound contained in the aforementioned ionic polyisocyanate compound (A) to the structural unit (b2) derived from the nonionic compound contained in the aforementioned nonionic polyisocyanate compound (B) is 50 / 50 or more and 98 / 2 or less.

[0020] (2) The polyisocyanate composition according to (1), wherein the mass ratio (A) / (B) of the aforementioned ionic polyisocyanate compound (A) to the aforementioned nonionic polyisocyanate compound (B) is 10 / 90 or more and 99 / 1 or less.

[0021] (3) The polyisocyanate composition according to (1) or (2), wherein the aforementioned polyisocyanate composition contains isocyanurate group, ureidone group and ureocarboxylate group,

[0022] Relative to the total molar amount of the aforementioned isocyanurate group, the aforementioned urea diketone group, the iminooxadiazine diketone group, and the aforementioned urea formate group, the total content of the aforementioned urea diketone group and the aforementioned urea formate group is 1.0 mol% or more and 30.0 mol% or less, and

[0023] The molar ratio of the aforementioned diketone group to the aforementioned urethane group is 0.1 or more and 20.0 or less.

[0024] (4) The polyisocyanate composition according to any one of (1) to (3), wherein, relative to the total mass of the aforementioned polyisocyanate composition, the mass fraction of the aforementioned ionic compound bonded to the aforementioned ionic polyisocyanate compound (A) is 1% by mass or more and 40.0% by mass or less.

[0025] (5) The polyisocyanate composition according to any one of (1) to (4), wherein, relative to the total mass of the aforementioned polyisocyanate composition, the mass fraction of the aforementioned nonionic compound bonded to the aforementioned nonionic polyisocyanate compound (B) is 0.1% by mass or more and 10.0% by mass or less.

[0026] (6) The polyisocyanate composition according to any one of (1) to (5), wherein the aforementioned nonionic compound is a polyalkylene glycol alkyl ether having the structure shown in the following general formula (I).

[0027]

[0028] (In general formula (I), R) 11 R is an alkylene group having 1 or more but less than 4 carbon atoms. 12 It is an alkyl group with 1 or more but less than 4 carbon atoms, and n11 is 4.0 or more but less than 20.

[0029] (7) The polyisocyanate composition according to any one of (1) to (6), wherein the aforementioned anionic compound is one or more compounds selected from the group consisting of compounds containing a carboxylic acid group, compounds containing a phosphate group, and compounds containing a sulfonic acid group.

[0030] (8) The polyisocyanate composition according to any one of (1) to (7), wherein the aforementioned anionic compound comprises a compound containing a sulfonic acid group, and the aforementioned compound containing a sulfonic acid group is one or more sulfonic acids selected from the group consisting of sulfonic acids containing hydroxyl groups and sulfonic acids containing amino groups.

[0031] (9) The polyisocyanate composition according to (8), wherein the aforementioned sulfonic acid containing hydroxyl groups is a compound represented by the following general formula (II).

[0032] HO-R 2l -SO3H (II)

[0033] (In general formula (II), R) 21R is a hydrocarbon group consisting of at least one of the groups selected from hydroxyl, ether, ester, carbonyl, and imino, with 1 or more but less than 10 carbon atoms. 21 The ring structure can be optionally included. The aforementioned ring structure can be an aromatic ring, a five- or six-membered ring containing two nitrogen atoms, or a five- or six-membered ring containing both nitrogen and oxygen atoms.

[0034] (10) The polyisocyanate composition according to (8), wherein the aforementioned amino-containing sulfonic acid is a compound represented by the following general formula (III).

[0035]

[0036] (In general formula (III), R) 31 and R 32 Each group is independently a hydrogen atom or, optionally, a hydrocarbon group containing a hydroxyl group and having 1 or more but less than 12 carbon atoms. R 32 and R 33 At least one of them is a hydrogen atom. R 33 (This can be any hydrocarbon group containing a hydroxyl group and having 1 or more but less than 12 carbon atoms.)

[0037] (11) The polyisocyanate composition according to any one of (1) to (10), wherein at least a portion of the isocyanate groups of the aforementioned ionic polyisocyanate compound (A) and / or the aforementioned nonionic polyisocyanate compound (B) are capped by a thermally dissociative capping agent.

[0038] (12) A coating composition comprising any one of (1) to (11) a polyisocyanate composition and a resin.

[0039] (13) A coating substrate coated with the coating composition described in (12).

[0040] The effects of the invention

[0041] The polyisocyanate composition according to the above method provides a polyisocyanate composition that exhibits excellent shelf life and dispersibility when dispersed in water or a water-containing main agent, and excellent appearance, water resistance, and hardness when formed into a coating film. The coating composition according to the above method comprises the aforementioned polyisocyanate composition, and its coating film exhibits excellent appearance, water resistance, and hardness. The coating substrate according to the above method comprises a coating film formed by curing the aforementioned coating composition, exhibiting excellent appearance, water resistance, and hardness. Detailed Implementation

[0042] The following is a detailed description of a method for implementing the present invention (hereinafter referred to as "this embodiment"). It should be noted that the present invention is not limited to this embodiment. The present invention can be implemented with appropriate modifications within its scope.

[0043] Polyisocyanate Compositions

[0044] The polyisocyanate composition of this embodiment comprises an ionic polyisocyanate compound (A) and a nonionic polyisocyanate compound (B).

[0045] The ionic polyisocyanate compound (A) is derived from the polyisocyanate compound (a1) and one or more ionic compounds selected from the group consisting of anionic and cationic compounds.

[0046] The nonionic polyisocyanate compound (B) is derived from the nonionic compound and the polyisocyanate compound (b1).

[0047] Polyisocyanate compound (a1) and polyisocyanate compound (b1) are polyisocyanate compounds derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates.

[0048] In the polyisocyanate composition of this embodiment, the mass ratio (A) / (B) of the ionic polyisocyanate compound (A) to the nonionic polyisocyanate compound (B) is preferably 10 / 90 or more and 99 / 1 or less.

[0049] The upper limit of the mass ratio (A) / (B) is more preferably 98 / 2, further preferably 95 / 5, and particularly preferably 90 / 10. On the other hand, the lower limit of the mass ratio (A) / (B) is more preferably 40 / 60, further preferably 50 / 50, even more preferably 60 / 40, particularly preferably 70 / 30, and most preferably 80 / 20.

[0050] By setting the mass ratio (A) / (B) within the above range, an excellent shelf life is achieved when the main agent is dispersed in water or contains water, and the resulting coating exhibits excellent gloss, hardness, and water resistance.

[0051] In the polyisocyanate composition of this embodiment, the mass ratio (a2) / (b2) of the structural unit (a2) derived from the ionic compound contained in the ionic polyisocyanate compound (A) to the structural unit (b2) derived from the nonionic compound contained in the nonionic polyisocyanate compound (B) is 50 / 50 or more and 98 / 2 or less.

[0052] The mass ratio (a2) / (b2) is preferably 60 / 40 or more and 97 / 3 or less, more preferably 70 / 30 or more and 95 / 5 or less, and even more preferably 80 / 20 or more and 90 / 10 or less.

[0053] By making the mass ratio (a2) / (b2) within the above range, it exhibits excellent shelf life when dispersed in water and water-containing main agents, and the resulting coating film has excellent gloss, hardness and water resistance.

[0054] The mass ratios (A) / (B) and (a2) / (b2) can be determined using liquid chromatography-mass spectrometry (LC-MS). Specifically, using a polyisocyanate composition as a sample, the modification rate of ionic polyisocyanate (A) based on ionic compounds and the modification rate of nonionic polyisocyanate (B) based on nonionic compounds are calculated based on the peak area ratio of ionic polyisocyanate (A), nonionic polyisocyanate (B), and unmodified polyisocyanate compound at 220 nm in liquid chromatography (LC). Then, the content of ionic polyisocyanate (A) and nonionic polyisocyanate (B) is calculated using the obtained modification rates, thereby determining the mass ratio (A) / (B). Furthermore, the ratio of the modification rate of ionic polyisocyanate (A) based on ionic compounds to the modification rate of nonionic polyisocyanate (B) based on nonionic compounds is set as the mass ratio (a2) / (b2).

[0055] Examples of LC-based determination conditions for nonionic polyisocyanates (B) and unmodified polyisocyanate compounds include the following.

[0056] (Measurement conditions)

[0057] LC device: Waters Corporation, UPLC (trade name)

[0058] Column: Waters Corporation, ACQUITY UPLC HSS T3 1.8μm C18, inner diameter 2.1mm × length 50mm

[0059] Flow rate: 0.3 mL / min

[0060] Mobile phase: A = 10 mM ammonium acetate aqueous solution, B = acetonitrile

[0061] Gradient conditions: The initial mobile phase composition is A / B = 98 / 2 (volume ratio). After the sample is injected, the ratio of B increases linearly, and after 10 minutes, A / B = 0 / 100 (volume ratio) is achieved.

[0062] Detection method: photodiode array detector, measurement wavelength 220nm

[0063] Ionic polyisocyanates (A) can be determined by adding the following conditions to the above determination conditions.

[0064] (Additional measurement conditions)

[0065] Ionization modes: electrospray ionization, positive and negative ion detection

[0066] Scan range: m / z 100~2000

[0067] The polyisocyanate composition of this embodiment, having the above-described structure, can achieve excellent shelf life and dispersibility when dispersed in water or in a water-containing main agent, as shown in the examples described later, and can produce a coating film with excellent appearance, hardness and water resistance.

[0068] It should be noted that the "shelf life" mentioned here refers to the time during which the composition, before curing, is maintained after the main agent and curing agent are mixed to prepare the composition for coatings, adhesives, etc., and is also called the usable time. As shown in the examples described later, the evaluation can be carried out by measuring the time during which the isocyanate groups in the coating composition prepared by mixing the polyisocyanate composition (curing agent) of this embodiment with the main agent remain at 80 mol% or more.

[0069] The components of the polyisocyanate composition of this embodiment will be described in detail.

[0070] <Ionic polyisocyanates (A) and nonionic polyisocyanates (B)>

[0071] The polyisocyanate composition of this embodiment includes ionic polyisocyanate (A) and nonionic polyisocyanate (B). Hereinafter, ionic polyisocyanate (A) and nonionic polyisocyanate (B) are sometimes collectively referred to as hydrophilic polyisocyanate compounds.

[0072] The polyisocyanate composition of this embodiment may further include polyisocyanates that do not contain ionic or nonionic functional groups within the molecule (hereinafter sometimes referred to as "unmodified polyisocyanate (C)"). Unless otherwise specified, the various properties of the polyisocyanate composition of this embodiment described below are those exhibited in the presence of ionic polyisocyanate (A), nonionic polyisocyanate (B), and unmodified polyisocyanate (C).

[0073] Ionic polyisocyanates (A) are compounds obtained by reacting an ionic compound with a polyisocyanate compound (a1), that is, they are reactants of an ionic compound and a polyisocyanate compound (a1). As an ionic compound, it is one or more compounds selected from the group consisting of anionic and cationic compounds.

[0074] Nonionic polyisocyanate (B) is a compound obtained by reacting a nonionic compound with a polyisocyanate compound (b1), that is, it is a reactant of a nonionic compound and a polyisocyanate compound (b1).

[0075] Polyisocyanate compound (a1) and polyisocyanate compound (b1) are each independently a polyisocyanate compound derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates.

[0076] Polyisocyanate compound (a1) and polyisocyanate compound (b1) can be the same compound or different compounds. Hereinafter, polyisocyanate compound (a1) and polyisocyanate compound (b1) will sometimes be referred to collectively as "polyisocyanate compound".

[0077] [Polyisocyanate compounds]

[0078] The polyisocyanate compounds used as raw materials for ionic polyisocyanates (A) and nonionic polyisocyanates (B) are polyisocyanate compounds derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates.

[0079] As aliphatic diisocyanates, there are no particular limitations, and examples include 1,4-diisocyanate butane, 1,5-diisocyanate pentane, ethyl (2,6-diisocyanate)hexanoate, 1,6-diisocyanate hexane (hereinafter sometimes referred to as "HDI"), 1,9-diisocyanate nonane, 1,12-diisocyanate dodecane, 2,2,4- or 2,4,4-trimethyl-1,6-diisocyanate hexane, etc.

[0080] As alicyclic diisocyanates, there are no particular limitations, and examples include 1,3-bis(isocyanate methyl)cyclohexane or 1,4-bis(isocyanate methyl)cyclohexane (hereinafter sometimes referred to as "hydrogenated XDI"), 1,3-diisocyanate cyclohexane or 1,4-diisocyanate cyclohexane, 3,5,5-trimethyl-1-isocyanate-3-(isocyanate methyl)cyclohexane (hereinafter sometimes referred to as "IPDI"), 4,4'-diisocyanate dicyclohexylmethane (hereinafter sometimes referred to as "hydrogenated MDI"), 2,5-diisocyanate methyl norbornane or 2,6-diisocyanate methyl norbornane, etc.

[0081] As an aromatic diisocyanate, there are no particular limitations; examples include phenylene diisocyanate, toluene diisocyanate, and diphenylmethane diisocyanate.

[0082] From the viewpoint of weather resistance, HDI, IPDI, hydrogenated XDI or hydrogenated MDI are preferred as diisocyanates, and HDI or IPDI are more preferred.

[0083] Furthermore, the polyisocyanate compound may include aliphatic triisocyanates. Examples of aliphatic triisocyanates include 1,3,6-triisocyanate hexane, 1,8-diisocyanate-4-isocyanate methyl octane, and 2-isocyanate ethyl-2,6-diisocyanate hexane ester.

[0084] Furthermore, these polyisocyanate compounds can be used alone, or in combination of two or more.

[0085] The polyisocyanate compounds derived from diisocyanates mentioned above are not particularly limited, and examples such as the polyisocyanates shown in (a) to (h) below can be listed.

[0086] (a) A polyisocyanate having a diuret group obtained by cyclizing and dimerizing two isocyanate groups;

[0087] (b) A polyisocyanate having an isocyanurate group or an iminooxadiazine dione group obtained by cyclizing and trimerizing three isocyanate groups;

[0088] (c) A polyisocyanate having a biuret group obtained by reacting three isocyanate groups with one water molecule;

[0089] (d) A polyisocyanate having an oxadiazine trione group obtained by reacting two isocyanate groups with one molecule of carbon dioxide;

[0090] (e) A polyisocyanate having multiple urethane groups obtained by reacting one isocyanate group with one hydroxyl group;

[0091] (f) A polyisocyanate having a urea carbamate group obtained by reacting two isocyanate groups with a hydroxyl group;

[0092] (g) A polyisocyanate having an acylurea group obtained by reacting an isocyanate group with a carboxyl group;

[0093] (h) A polyisocyanate having a urea group obtained by reacting an isocyanate group with a primary or secondary amine.

[0094] Among them, as a polyisocyanate compound, it is preferred to have an isocyanurate group, a diuret group or a urethane group in the molecule.

[0095] Furthermore, the polyisocyanate composition of this embodiment preferably contains isocyanurate groups, urea diketone groups, and urea formate groups. That is, the polyisocyanate composition of this embodiment may contain a mixture of polyisocyanate compounds having one of these functional groups, or it may contain a mixture of two or more polyisocyanate compounds having two or more of these functional groups, or it may contain a polyisocyanate compound having three of these functional groups.

[0096] The urea diketone group refers to the functional group obtained by cyclizing and dimerizing two isocyanate groups, as shown in formula (a) below. Polyisocyanates containing the urea diketone group have low viscosity and good dispersibility.

[0097] The isocyanurate group is a functional group obtained by cyclizing and trimerizing three isocyanate groups, and refers to the structure shown in formula (b1) below.

[0098] The iminooxadiazine dione group is a functional group obtained by cyclizing and trimerizing three isocyanate groups, and refers to the structure shown in formula (b2) below.

[0099] The urea-formate group is a functional group formed by the reaction of the hydroxyl group of an alcohol with the isocyanate group, and refers to the structure shown in formula (f) below.

[0100] It should be noted that in the various formulas, the wavy line represents the connecting bond, which is the site that is bonded to the residue after removing one of the isocyanate groups in the polyisocyanate.

[0101]

[0102] In the polyisocyanate composition of this embodiment, the molar ratio of isocyanurate groups relative to the total molar amount (100 mol%) of isocyanurate groups, iminooxadiazine dione groups, urea dione groups, and urea carbamate groups is preferably 70.0 mol% or more and 90.0 mol% or less, more preferably 80.0 mol% or more and 88.0 mol% or less. By keeping the molar ratio of isocyanurate groups within the above range, the resulting coating film exhibits superior water resistance and hardness.

[0103] In the polyisocyanate composition of this embodiment, the molar ratio of iminooxadiazine dione group relative to the total molar amount (100 mol%) of isocyanurate group, iminooxadiazine dione group, urea dione group and urea carbamate group is preferably 1.0 mol% or more and 3.5 mol% or less, more preferably 2.0 mol% or more and 3.0 mol% or less.

[0104] In the polyisocyanate composition of this embodiment, the molar ratio of urea carbamate groups relative to the total molar amount (100 mol%) of isocyanurate groups, iminooxadiazine dione groups, urea dione groups, and urea carbamate groups is preferably 0.1 mol% or more and 30.0 mol% or less, more preferably 1.0 mol% or more and 20.0 mol% or less.

[0105] In the polyisocyanate composition of this embodiment, the molar ratio of urea diketone groups relative to the total molar amount (100 mol%) of isocyanurate groups, iminooxadiazine diketone groups, urea diketone groups, and urea carbamate groups is preferably 0.1 mol% or more and 30.0 mol% or less, more preferably 0.2 mol% or more and 25.0 mol% or less.

[0106] In the polyisocyanate composition of this embodiment, the total content of urea diketone and urea formate groups is preferably 1.0 mol% or more and 30.0 mol% or less, more preferably 2.0 mol% or more and 25.0 mol% or less, relative to the total molar amount (100 mol%) of isocyanurate groups, iminooxadiazine diketone groups, urea diketone groups and urea formate groups.

[0107] The molar ratio of diketone groups to urethane groups (diketone / urethane group) is preferably 0.1 or more and 20.0 or less, more preferably 0.2 or more and 10.0 or less, and even more preferably 0.3 or more and 5.0 or less. By keeping the total content of diketone and urethane groups and the diketone / urethane group ratio within the above range, the polyisocyanate composition has a longer shelf life, and the resulting coating film has better gloss, hardness, and water resistance.

[0108] The content of the above-mentioned structures derived from isocyanate groups in the polyisocyanate composition of this embodiment can be utilized. 13 The determination was made using C-NMR spectroscopy. Specifically, the determination was performed using a Biospin Avance 600 (trade name) manufactured by Bruker under the following conditions.

[0109] (Measurement conditions)

[0110] 13 C-NMR apparatus: AVANCE 600 (manufactured by Bruker)

[0111] CryoProbe (manufactured by Bruker)

[0112] CryoProbe (registered trademark)

[0113] CPDUL

[0114] 600S3-C / HD-05Z

[0115] Resonant frequency: 150MHz

[0116] Concentration: 60 wt / vol%

[0117] Displacement reference: CDCl3 (77ppm)

[0118] Total number of times: 10,000

[0119] Pulse program: zgpg30 (complete proton decoupling, waiting time 2 seconds)

[0120] The mole fraction of each group relative to the total (100 mol%) of isocyanurate, iminooxadiazine dione, ureacarbate, and urea dione groups is determined by dividing the integral value of the following signals by the measured number of carbon atoms. Using the obtained mole fractions, the total content of urea dione and urea carbamate groups relative to the total molar amount of isocyanurate, iminooxadiazine dione, urea dione, and urea carbamate groups, as well as the molar ratio of urea dione to urea carbamate groups (urea dione / urea carbamate molar ratio) are calculated.

[0121] Isocyanurate group: (integral value around 148.6 ppm) ÷ 3

[0122] Iminooxadiazine diketoyl: (Integral value around 135.5 ppm) ÷ 1

[0123] Urea carbamate group: (integral value around 154ppm) ÷ 1

[0124] Ureadione structure: (Integral value around 157 ppm) ÷ 2

[0125] (Methods for manufacturing polyisocyanate compounds)

[0126] (1) Method for manufacturing polyisocyanates containing isocyanurate groups

[0127] There are no particular limitations on the method for manufacturing polyisocyanates containing isocyanurate groups. Examples include the following method: using a catalyst or the like to carry out an isocyanurate reaction of diisocyanate, stopping the reaction when a predetermined conversion rate is reached, and removing unreacted diisocyanate.

[0128] The catalyst used in the isocyanurate esterification reaction is not particularly limited, but a catalyst exhibiting basicity is preferred. Specifically, examples include hydroxides of tetraalkylammonium and organic weak acid salts, hydroxides of hydroxyalkylammonium and organic weak acid salts, alkali metal salts of alkylcarboxylic acids, metal alkoxides, compounds containing aminomethylsilyl groups, Mannich bases, combinations of tertiary amines and epoxides, and phosphorus compounds.

[0129] Examples of tetraalkylammonium compounds include tetramethylammonium and tetraethylammonium.

[0130] Examples of weak organic acids include acetic acid and decanoic acid. Examples of hydroxyalkyl ammonium compounds include trimethylhydroxypropylammonium, trimethylhydroxyethylammonium, triethylhydroxypropylammonium, and triethylhydroxyethylammonium.

[0131] Examples of alkyl carboxylic acids include acetic acid, hexanoic acid, octanoic acid, and myristic acid.

[0132] Examples of metals that constitute alkali metal salts include tin, zinc, and lead.

[0133] Examples of metal alkoxides include sodium alkoxides and potassium alkoxides.

[0134] Examples of compounds containing aminomethylsilyl groups include hexamethyldisilazane.

[0135] Examples of phosphorus compounds include tributylphosphine.

[0136] The amount of these catalysts used is preferably 10 ppm or more and 1.0% or less relative to the total mass of the diisocyanate (and alcohol as needed) used as raw materials. Furthermore, to terminate the isocyanurate esterification reaction, an acidic substance for neutralizing the catalyst can be added; inerting can be performed through thermal decomposition, chemical decomposition, etc. Examples of acidic substances for neutralizing the catalyst include phosphoric acid and acid phosphate esters.

[0137] The yield of polyisocyanates typically tends to be 10% by mass or more and 70% by mass or less, preferably 35% by mass or more and 60% by mass or less. Polyisocyanates obtained at higher yields tend to have higher viscosity. The yield can be calculated as the ratio of the mass of the obtained polyisocyanate to the total mass of the feedstock components.

[0138] The reaction temperature for the isocyanurate esterification 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. By setting the reaction temperature above the lower limit, the reaction tends to proceed more easily, and by setting the reaction temperature below the upper limit, side reactions such as coloring initiation tend to be further suppressed.

[0139] Preferably, after the isocyanurate esterification reaction, unreacted diisocyanate is removed by means of a thin-film evaporation vessel or extraction. Even when the polyisocyanate contains unreacted diisocyanate, the diisocyanate content relative to the total mass of the polyisocyanate is preferably 3.0% by mass or less, more preferably 1.0% by mass or less, and even more preferably 0.5% by mass or less. By keeping the concentration of residual unreacted diisocyanate within the above range, there is a tendency for better curability.

[0140] The concentration of residual unreacted diisocyanate can be determined by gas chromatography.

[0141] (2) Method for manufacturing polyisocyanates containing urea carbamate groups

[0142] As a method for producing polyisocyanates containing urea-formate groups, it can be obtained, for example, by adding an alcohol to a diisocyanate and using a urea-formate reaction catalyst.

[0143] The alcohol used to form the urethane group is preferably an alcohol formed only by carbon, hydrogen and oxygen.

[0144] The alcohols mentioned above, specifically, are not limited to the following, but can include, for example, monools and diols. These alcohols can be used alone or in combination of two or more.

[0145] Examples of monools include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, and nonanol.

[0146] Examples of diols include ethylene glycol, 1,3-butanediol, neopentyl glycol, and 2-ethylhexanediol.

[0147] Among them, the alcohol is preferably a monool, and more preferably a monool with a molecular weight of 200 or less.

[0148] The molar ratio of the isocyanate group to the hydroxyl group of the alcohol in the diisocyanate is preferably 10 / 1 or more and 1000 / 1 or less, more preferably 100 / 1 or more and 1000 / 1 or less. By setting this molar ratio to the lower limit or above, the average number of isocyanate groups (average number of functional groups) can be more adequately ensured. By setting this molar ratio to the upper limit or below, excellent surface hardness is achieved.

[0149] While not limited to the following, examples of alkyl carboxylates such as tin, lead, zinc, bismuth, zirconium, and zirconium oxycarboxylates can be used as catalysts for urea carboxylation reactions.

[0150] Examples of alkyl carboxylates (organotin compounds) of tin include tin 2-ethylhexanoate and tin dibutyl dilaurate.

[0151] Examples of alkyl carboxylates (organolead compounds) of lead include lead 2-ethylhexanoate.

[0152] Examples of alkyl carboxylates (organozinc compounds) of zinc include zinc 2-ethylhexanoate.

[0153] Examples of alkyl carboxylates of bismuth include bismuth 2-ethylhexanoate.

[0154] Examples of alkyl carboxylates of zirconium include zirconium 2-ethylhexanoate.

[0155] Examples of alkyl carboxylates that are zirconium oxycarboxylate groups include, for example, 2-ethylhexanoate zirconium oxycarboxylate.

[0156] These catalysts can be used alone or in combination of two or more.

[0157] Furthermore, the aforementioned isocyanurate esterification catalyst can also serve as a catalyst for ureacarboxylation. When using the aforementioned isocyanurate esterification catalyst for ureacarboxylation, isocyanurate-type polyisocyanates will naturally be generated.

[0158] Using the above-mentioned isocyanurate esterification catalyst as the catalyst for urea carbamate esterification reaction is preferred from an economical production perspective.

[0159] The upper limit of the amount of the catalyst used in the urea esterification reaction is preferably 10,000 ppm by mass relative to the mass of the diisocyanate fed, more preferably 1,000 ppm by mass, and even more preferably 500 ppm by mass. On the other hand, the lower limit of the amount of the catalyst used in the urea esterification reaction is not particularly limited, for example, it can be 10 ppm by mass.

[0160] Furthermore, the lower limit of the urea-formylation reaction temperature is preferably 60°C, more preferably 70°C, even more preferably 80°C, and particularly preferably 90°C. On the other hand, the upper limit of the urea-formylation reaction temperature is preferably 160°C, more preferably 155°C, even more preferably 150°C, and particularly preferably 145°C.

[0161] That is, the urea-formylation reaction temperature is preferably 60°C or higher and 160°C or lower, more preferably 70°C or higher and 155°C or lower, even more preferably 80°C or higher and 150°C or lower, and particularly preferably 90°C or higher and 145°C or lower.

[0162] By setting the urea-formylation reaction temperature above the aforementioned lower limit, the reaction rate can be further increased. By setting the urea-formylation reaction temperature below the aforementioned upper limit, there is a tendency to more effectively suppress changes in the coloring and other properties of the polyisocyanate.

[0163] The lower limit of the urea-formylation reaction time is preferably 0.2 hours, more preferably 0.4 hours, further preferably 0.6 hours, particularly preferably 0.8 hours, and most preferably 1 hour. On the other hand, the upper limit of the urea-formylation reaction time is preferably 8 hours, more preferably 6 hours, further preferably 4 hours, particularly preferably 3 hours, and most preferably 2 hours.

[0164] That is, the urea-formaldehyde esterification reaction time is preferably 0.2 hours or more and 8 hours or less, more preferably 0.4 hours or more and 6 hours or less, even more preferably 0.6 hours or more and 4 hours or less, particularly preferably 0.8 hours or more and 3 hours or less, and most preferably 1 hour or more and 2 hours or less.

[0165] By setting the urea-formylation reaction time to the lower limit or above, the viscosity of the polyisocyanate can be reduced. On the other hand, by setting it to the upper limit or below, there is a tendency to more effectively suppress changes in the coloring and other properties of the polyisocyanate.

[0166] At the point where the desired yield is reached, deactivators of the urea-formylation catalyst, such as phosphoric acid or methyl p-toluenesulfonate, are added to stop the urea-formylation reaction.

[0167] In polyisocyanates, the molar ratio of urea groups to isocyanurate groups (hereinafter sometimes referred to as "urea group / isocyanurate group") is preferably 0.50 or less from the viewpoint of improving crosslinking properties. The molar ratio of urea group / isocyanurate group can be determined by... 13 It is determined by C-NMR.

[0168] (3) Method for manufacturing polyisocyanates containing urea diketone groups

[0169] As a method for manufacturing polyisocyanates containing ureidone groups, one example is the use of a ureidone reaction catalyst.

[0170] Examples of specific compounds that can act as catalysts for the above-mentioned ureidodiketation reaction include, but are not limited to, trialkylphosphines such as tri-n-butylphosphine and tri-n-octylphosphine, which are tertiary phosphines; tri(dimethylamino)phosphine and tri(dialkylamino)phosphine; and cyclohexyldi-n-hexylphosphine and cycloalkylphosphine.

[0171] Most of these compounds also promote isocyanurate esterification reactions, generating polyisocyanates containing isocyanurate groups in addition to polyisocyanates containing diurea groups.

[0172] At the point where the desired yield is reached, deactivators of the ureidodiketation catalyst, such as phosphoric acid or methyl p-toluenesulfonate, are added to stop the ureidodiketation reaction.

[0173] The catalyst described above is used in an amount that is preferably 10 ppm or more and 10,000 ppm or less relative to the mass of the diisocyanate fed into the feed, more preferably 10 ppm or more and 1,000 ppm or less, and even more preferably 10 ppm or more and 500 ppm or less relative to the mass of the diisocyanate fed into the feed.

[0174] The ureidodiketation reaction temperature is preferably between 20°C and 120°C. The lower limit of the reaction temperature is more preferably 25°C, further preferably 30°C, and even more preferably 35°C. Furthermore, the upper limit of the reaction temperature is more preferably 110°C, further preferably 100°C, and even more preferably 90°C. By keeping the ureidodiketation reaction temperature below the above-mentioned upper limit, there is a tendency to further suppress changes in properties such as coloring.

[0175] Furthermore, ureidone groups can also be obtained by heating diisocyanate without using the catalyst described above. The heating temperature is preferably 130°C or higher and 180°C or lower. The lower limit of the heating temperature is more preferably 140°C, further preferably 145°C, even more preferably 150°C, and still more preferably 155°C. Furthermore, the upper limit of the heating temperature is more preferably 170°C, further preferably 165°C, even more preferably 162°C, and still more preferably 160°C.

[0176] Furthermore, the heating time is preferably 0.2 hours or more and 8.0 hours or less. The lower limit of the heating time is more preferably 0.4 hours, further preferably 0.6 hours, even more preferably 0.8 hours, and still more preferably 1.0 hour. The upper limit of the heating time is more preferably 6.0 hours, further preferably 4.0 hours, even more preferably 3.0 hours, and still more preferably 2.0 hours. By setting the heating time to the lower limit or above, there is a tendency to further exhibit lower viscosity; by setting it to the upper limit or below, there is a tendency to further suppress the coloring of the polyisocyanate itself.

[0177] When obtaining the polyisocyanate composition of this embodiment without using a ureidodiketation reaction catalyst, from the viewpoint of reducing the concentration of unreacted diisocyanate, reducing the rate of change of molecular weight of the obtained polyisocyanate composition after storage, and reducing yellowing during high-temperature sintering, it is preferable to remove the unreacted diisocyanate after the completion of the ureidodiketation reaction based solely on heating and the above-mentioned isocyanurate esterification reaction.

[0178] (Physical properties of polyisocyanate compounds)

[0179] From the viewpoint of improving the dispersibility and shelf life of the coating composition, and improving the appearance and water resistance of the coating film, the viscosity of the polyisocyanate compound at 25°C is preferably 300 mPa·s or more and 5,000 mPa·s or less.

[0180] From the viewpoint of improving the water resistance and weather resistance of the formed coating film, the lower limit of viscosity is more preferably 350 mPa·s, and even more preferably 450 mPa·s. On the other hand, from the viewpoint of improving dispersibility and shelf life, the upper limit of viscosity is more preferably 4,000 mPa·s, and even more preferably 3,000 mPa·s.

[0181] The viscosity of polyisocyanate compounds can be measured using, for example, a standard rotor (1°34'×R24) and an E-type viscometer (TOKIMEC) at 25°C.

[0182] In the state after removing unreacted aliphatic diisocyanates, the isocyanate group content (NCO%) of the polyisocyanate compound is preferably 18% by mass or more and 25% by mass or less, more preferably 19% by mass or more and 24% by mass or less, and even more preferably 20% by mass or more and 24% by mass or less.

[0183] By setting the isocyanate group content above the lower limit mentioned above, the water resistance, chemical resistance, and weather resistance of the resulting coating film are further improved. On the other hand, by setting it below the upper limit mentioned above, the dispersibility and shelf life of the coating composition are further improved, and the appearance of the resulting coating film is better.

[0184] The isocyanate group content (NCO%) of the polyisocyanate compound can be determined using the titration method described in the examples below.

[0185] From the viewpoint of solvent resistance of the coating film, the number average molecular weight of the polyisocyanate compound is preferably 450 or more and 4000 or less, more preferably 500 or more and 3500 or less, and even more preferably 550 or more and 3000 or less.

[0186] Number-average molecular weight can be determined using, for example, gel permeation chromatography (GPC).

[0187] From the viewpoints of solvent resistance of the coating and isocyanate group retention, the average number of functional groups of the polyisocyanate compound 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.

[0188] The average number of functional groups is the number of isocyanate functional groups statistically present in one molecule of polyisocyanate compound, which can be calculated using the following formula from the number average molecular weight (Mn) and isocyanate group content (NCO%) of the polyisocyanate compound.

[0189] [Average number of functional groups] = Mn × NCO% / 4200

[0190] [Ionic compounds and nonionic compounds]

[0191] The raw materials for ionic polyisocyanates, i.e., ionic compounds, are compounds with ionic functional groups.

[0192] The raw materials for nonionic polyisocyanate compounds, i.e., nonionic compounds are compounds that possess nonionic properties.

[0193] Hereinafter, ionic and nonionic compounds will sometimes be collectively referred to as hydrophilic compounds. Furthermore, ionic and nonionic functional groups will sometimes be collectively referred to as hydrophilic groups.

[0194] In hydrophilic compounds, in order to react with an isocyanate group, it is preferable to have one or more active hydrogen groups relative to one molecule of hydrophilic compound, which are capable of reacting with the isocyanate groups present in polyisocyanate compounds. Specifically, examples of active hydrogen groups include hydroxyl, mercapto, carboxylic acid, amino, and thiol groups.

[0195] Ionic compounds can be categorized into anionic and cationic compounds. Nonionic compounds are also called nonion compounds. These hydrophilic compounds can be used alone or in combination of two or more.

[0196] (Anionic compounds)

[0197] There are no particular limitations on anionic compounds; examples include compounds containing carboxylic acid groups, compounds containing phosphoric acid groups, and compounds containing sulfonic acid groups.

[0198] The compounds containing a carboxylic acid group are not particularly limited, and examples include monohydroxycarboxylic acids such as 1-hydroxyacetic acid, 3-hydroxypropionic acid, 12-hydroxy-9-octadecanoic acid, hydroxypentanoic acid, and lactic acid; and polyhydroxycarboxylic acids such as dihydroxymethylacetic acid, 2,2-dihydroxymethylbutyric acid, 2,2-dihydroxymethylpentanoic acid, dihydroxysuccinic acid, and dihydroxymethylpropionic acid. Hydroxypentanoic acid or dihydroxymethylpropionic acid is preferred.

[0199] The compounds containing phosphate groups are not particularly limited, and examples include acid phosphate esters, acid phosphites, acid hypophosphites, and specific polyether phosphonates (e.g., substances commercially available under the trade name RHODAFAC (registered trademark) (Solvay Nicca)). Among these, acid phosphate esters are preferred.

[0200] From the viewpoint of water dispersibility, the content of phosphorus atoms in the polyisocyanate composition, relative to the total amount (100% by mass) of the polyisocyanate composition, is preferably 0.03% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more. By making the phosphorus atom content 0.03% by mass or more, there is a tendency to exhibit better water dispersibility due to the decrease in interfacial tension.

[0201] Furthermore, from the viewpoint of coating properties, the phosphorus atom content in the polyisocyanate composition is preferably 6.0% by mass or less, more preferably 3.0% by mass or less, and even more preferably 1.0% by mass or less, relative to the total amount (100% by mass) of the polyisocyanate composition. By keeping the phosphorus atom content below the above-mentioned upper limit, there is a tendency for the coating properties to become better due to the increased number of isocyanate groups used for crosslinking.

[0202] As a method for controlling the phosphorus atom content to the above-mentioned range, it is not limited to the following, but examples include adjusting the mixing ratio of the above-mentioned phosphoric acid-containing compound and the polyisocyanate compound used as a raw material. Furthermore, the phosphorus atom content is determined by inductively coupled plasma atomic emission spectrometry (ICP-AES).

[0203] As compounds containing sulfonic acid groups, there are no particular limitations; examples include sulfonic acids containing hydroxyl groups and sulfonic acids containing amino groups.

[0204] From the viewpoint of dispersibility and appearance, sulfonic acids containing hydroxyl groups are preferably compounds represented by the following general formula (II) (hereinafter sometimes referred to as "sulfonic acids containing hydroxyl groups (II)").

[0205] HO-R 21 -SO3H (II)

[0206] In general formula (II), R21 R is a hydrocarbon group having 1 or more and 10 or fewer carbon atoms, optionally comprising at least one of the following groups: hydroxyl, ether (-O-), ester (-COO-), carbonyl (-C(=O)-), and imino (-C(=NR)- or -C-(NR)-C-). 21 The ring structure may be optionally included. The aforementioned ring structure may be an aromatic ring, a five-membered or six-membered ring containing two nitrogen atoms, or a five-membered or six-membered ring containing nitrogen and oxygen atoms.

[0207] As R 21 The hydrocarbon group having 1 or more and 10 or less carbon atoms can be an aliphatic hydrocarbon group with 1 or more and 10 or less carbon atoms in a divalent form, or an aromatic hydrocarbon group with 6 or more and 10 or less carbon atoms in a divalent form. As an aliphatic hydrocarbon group with 1 or more and 10 or less carbon atoms in a divalent form, a chain-like alkylene group with 1 or more and 6 or less carbon atoms is preferred. In the case of a chain-like alkylene group with 1 or more and 6 or less carbon atoms, a group comprising a ring structure may be a part of the chain-like alkylene group. The alkylene group with 1 or more and 6 or less carbon atoms can be linear or branched.

[0208] Among them, as R 21 Preferably, it is a chain-like alkylene group with 1 or more and 6 or less carbon atoms, an aromatic hydrocarbon group (arylene) with 6 or more and 10 or less divalent carbon atoms, an alkylene group with 1 or more and 10 or less divalent carbon atoms containing an aromatic ring, an alkylene group with 1 or more and 6 or less divalent carbon atoms containing a five-membered ring or a six-membered ring containing two nitrogen atoms, or an alkylene group with 1 or more and 6 or less divalent carbon atoms containing a five-membered ring or a six-membered ring containing nitrogen atoms and oxygen atoms.

[0209] Preferred sulfonic acids (II) containing hydroxyl groups include, for example, 2-hydroxyethanesulfonic acid, 3-hydroxypropanesulfonic acid, 4-hydroxybutyric acid, 5-hydroxypentanesulfonic acid, 6-hydroxyhexanesulfonic acid, hydroxybenzenesulfonic acid, hydroxy(methyl)benzenesulfonic acid, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid, 2-hydroxy-3-morpholinopropanesulfonic acid, and specific polyether sulfonates (e.g., substances sold under the trade name Tegomer (registered trademark) (The Goldschmidt AG, Essen, Germany)).

[0210] Among them, the sulfonic acid having a hydroxyl group is preferably at least one selected from the group consisting of 2-hydroxyethanesulfonic acid, 3-hydroxypropanesulfonic acid, hydroxybenzenesulfonic acid and hydroxy(methyl)benzenesulfonic acid.

[0211] Examples of amino-containing sulfonic acids include compounds represented by the general formula (III) below (hereinafter sometimes referred to as "amino-containing sulfonic acids (III)").

[0212]

[0213] In general formula (III), R 31 and R 32 Each group is independently a hydrogen atom or, optionally, a hydrocarbon group containing a hydroxyl group and having 1 or more but less than 12 carbon atoms. R 32 and R 33 At least one of them is a hydrogen atom. R 33 It can be any hydrocarbon group containing 1 or more but less than 12 carbon atoms.

[0214] In general formula (III), R 31 and R 32 Each group is independently a hydrogen atom or, optionally, a hydrocarbon group containing a hydroxyl group and having 1 or more but less than 12 carbon atoms. R 31 and R 32 They can be either the same or different from each other. R 31 and R 32 At least one of them is a hydrogen atom. That is, R 31 When R is an optional hydrocarbon group containing a hydroxyl group and having 1 or more but less than 12 carbon atoms, 32 It is a hydrogen atom. Furthermore, R... 32 When R is an optional hydrocarbon group containing a hydroxyl group and having 1 or more but less than 12 carbon atoms, 31 It is a hydrogen atom. Furthermore, R... 31 and R 32 Both can be hydrogen atoms.

[0215] The hydrocarbon group having 1 or more and 12 or fewer carbon atoms can be an aliphatic hydrocarbon group with 1 or more and 12 or fewer carbon atoms in a monovalent state, or an aromatic hydrocarbon group with 6 or more and 12 or fewer carbon atoms in a monovalent state. Preferably, the aliphatic hydrocarbon group having 1 or more and 12 or fewer carbon atoms in a monovalent state is a chain alkyl group with 1 or more and 6 or fewer carbon atoms, or a cyclic alkyl group with 3 or more and 6 or fewer carbon atoms. The chain alkyl group having 1 or more and 6 or fewer carbon atoms can be straight-chain or branched.

[0216] Among them, as R 31 and R 32 Preferably, they are chain alkyl groups with 1 or more but less than 6 carbon atoms, or cyclic alkyl groups with 3 or more but less than 6 carbon atoms.

[0217] R 33 It can be any hydrocarbon group containing 1 or more but less than 12 carbon atoms.

[0218] The hydrocarbon group having 1 or more and 12 or fewer carbon atoms can be an aliphatic hydrocarbon group with 1 or more and 12 or fewer divalent carbon atoms, or an aromatic hydrocarbon group with 6 or more and 12 or fewer divalent carbon atoms. As an aliphatic hydrocarbon group with 1 or more and 12 or fewer divalent carbon atoms, a chain-like alkylene group with 1 or more and 12 or fewer carbon atoms is preferred. The chain-like alkyl group with 1 or more and 12 or fewer carbon atoms can be straight-chain or branched.

[0219] Among them, as R 33 Preferably, it is a chain alkylene group with 1 or more but less than 6 carbon atoms in the divalent group, or an aromatic hydrocarbon group (arylene group) with 6 or more but less than 10 carbon atoms in the divalent group.

[0220] Preferred amino-containing sulfonic acids (III) include, for example, 2-aminoethanesulfonic acid, 3-aminopropanesulfonic acid, 2-methylaminoethanesulfonic acid, 3-methylaminopropanesulfonic acid, 2-cyclohexylaminoethanesulfonic acid, 3-cyclohexylaminopropanesulfonic acid, 3-cyclohexylaminoisobutylsulfonic acid, 4-cyclohexylaminobutyric acid, 2-cyclohexylmethylaminoethanesulfonic acid, 3-cyclohexylmethylaminopropanesulfonic acid, 3-cyclohexylmethylaminoisobutylsulfonic acid, 4-cyclohexylmethylaminobutyric acid, 2-methylcyclohexylaminoethanesulfonic acid, 3-methylcyclohexylaminopropanesulfonic acid, 3-methylcyclohexylaminoisobutylsulfonic acid, 4-methylcyclohexylaminobutyric acid, 2-methylcyclohexylaminoethanesulfonic acid, 3-methylcyclohexylaminopropanesulfonic acid, 3-methylcyclohexylaminoisobutylsulfonic acid, 4-methylcyclohexylaminoethanesulfonic ...2-methylcyclohexylaminoethanesulfonic acid, 3-methylcyclohexylaminopropanesulfonic acid, 3-methylcyclohexylaminoisobutylsulfonic acid, 2-methylcyclohexylaminoethanesulfonic acid, 3-methylcyclohexyl Aminobutyric acid, 2-dimethylcyclohexylaminoethanesulfonic acid, 3-dimethylcyclohexylaminopropanesulfonic acid, 3-dimethylcyclohexylaminoisobutylsulfonic acid, 4-dimethylcyclohexylaminobutyric acid, 2-trimethylcyclohexylaminoethanesulfonic acid, 3-trimethylcyclohexylaminopropanesulfonic acid, 3-trimethylcyclohexylaminoisobutylsulfonic acid, 4-trimethylcyclohexylaminobutyric acid, 2-aminobenzenesulfonic acid, 3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 2-(methylamino)benzenesulfonic acid, 3-(methylamino)benzenesulfonic acid, 4-(methylamino)benzenesulfonic acid, amino-methylbenzenesulfonic acid, amino-dimethylbenzenesulfonic acid, aminonaphthalenesulfonic acid, etc.

[0221] The sulfonic acid having an amino group is preferably selected from at least one of the following: 2-cyclohexylaminoethanesulfonic acid, 3-cyclohexylaminopropanesulfonic acid, 4-cyclohexylaminobutyric acid, 3-cyclohexylmethylaminopropanesulfonic acid, 3-(p-methylcyclohexylamino)propanesulfonic acid, 3-(3,3,5-trimethylcyclohexylamino)propanesulfonic acid, 4-(p-methylcyclohexylamino)butyric acid, 2-aminobenzenesulfonic acid, 2-amino-5-methylbenzenesulfonic acid, 2-amino-3,5-dimethylbenzenesulfonic acid, 5-amino-2-methylbenzenesulfonic acid (4-aminotoluene-2-sulfonic acid), 4-amino-2-methylbenzenesulfonic acid (5-aminotoluene-2-sulfonic acid), and 2-aminonaphthalene-4-sulfonic acid.

[0222] For anionic compounds, acidic groups such as carboxylic acid groups, phosphoric acid groups, and sulfonic acid groups are preferably neutralized by inorganic bases or amine compounds.

[0223] Examples of inorganic bases include alkali metals such as lithium, sodium, potassium, rubidium, and cesium; alkaline earth metals such as magnesium, calcium, strontium, and barium; metals such as manganese, iron, cobalt, nickel, copper, zinc, silver, cadmium, lead, and aluminum; and ammonia.

[0224] Examples of amine compounds include:

[0225] Straight-chain tertiary amines such as trimethylamine, triethylamine, tripropylamine, tributylamine, trioctylamine, trilaurylamine, tri(tetranyl)amine, and tristearylamine;

[0226] Branched tertiary amines such as triisopropylamine, triisobutylamine, tri-2-ethylhexylamine, and tri(branched tridecyl)amine;

[0227] N,N-Dimethylethylamine, N,N-Dimethylpropylamine, N,N-Dimethylisopropylamine, N,N-Dimethylbutylamine, N,N-Dimethylisobutylamine, N,N-Dimethyloctylamine, N,N-Dimethyl-2-ethylhexylamine, N,N-Dimethyllaurylamine, N,N-Dimethyl(branched)tridecylamine, N,N-Dimethylstearylamine, 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, etc., are tertiary amines with mixed hydrocarbon groups;

[0228] Alicyclic tertiary amines include N,N-dimethylcyclohexylamine, N,N-diethylbenzylamine, N,N-diethylcyclohexylamine, N,N-dicyclohexylmethylamine, N,N-dicyclohexylethylamine, and tricyclohexylamine;

[0229] Tertiary amines with aromatic ring substituents, such as N,N-dimethylbenzylamine, N,N-diethylbenzylamine, N,N-dibenzylmethylamine, tribenzylamine, N,N-dimethyl-4-methylbenzylamine, N,N-dimethylphenylamine, N,N-diethylphenylamine, and N,N-diphenylmethylamine;

[0230] Cyclic amines such as N-methylpyrrolidine, N-ethylpyrrolidine, N-propylpyrrolidine, N-butylpyrrolidine, N-methylpiperidine, N-ethylpiperidine, N-propylpiperidine, N-butylpiperidine, N-methylmorpholine, N-ethylmorpholine, N-propylmorpholine, N-butylmorpholine, N-sec-butylmorpholine, N-tert-butylmorpholine, N-isobutylmorpholine, and quinine ring.

[0231] These amine compounds can be used alone or in combination of two or more.

[0232] Preferably, tertiary amines have 5 or more but less than 30 carbon atoms. Specifically, examples include triethylamine, tripropylamine, tributylamine, trioctylamine, trilaurylamine, tridecylamine, triisopropylamine, triisobutylamine, tri-2-ethylhexylamine, tri(branched tridecyl)amine, N,N-dimethylpropylamine, N,N-dimethylisopropylamine, N,N-dimethylbutylamine, N,N-dimethylisobutylamine, N,N-dimethyloctylamine, N,N-dimethyl-2-ethylhexylamine, N,N-dimethyllaurylamine, N,N-dimethyl(branched)tridecylamine, N,N-dimethylstearylamine, N,N-diethylbutylamine, N,N-dimethyl-2-ethylhexylamine, N,N-dimethyllaurylamine, N,N-dimethyl(branched)tridecylamine, N,N-dimethylstearylamine, 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-dimethylcyclohexylamine, N,N-diethylcyclohexylamine, N,N-dicyclohexylmethylamine, N,N-dicyclohexylethylamine, N,N-dimethylbenzylamine, N,N-diethylbenzylamine, N,N-dibenzylmethylamine, tribenzylamine, N,N-dimethylphenylamine, N,N-diethylphenylamine, N,N-diphenylmethylamine, N-methylpiperidine, N-ethylpiperidine, N-methylmorpholine, N-ethylmorpholine, quinine ring, pyridine, quinoline, etc. These preferred organic amine compounds can be used alone or in combination of two or more.

[0233] To disperse polyisocyanate compounds in water, hydrophilic compounds are used for modification (introducing hydrophilic groups derived from the hydrophilic compound into the polyisocyanate compound). By ensuring that the modification ratio is not too high, there is a tendency to suppress the decrease in coating properties (hardness, water resistance, and solvent resistance). Anionic compounds have high emulsifying power; therefore, a small amount can achieve a high emulsifying effect, enabling the polyisocyanate compound to be easily dispersed in water.

[0234] From the viewpoint of water dispersibility, the lower limit of the sulfur atom content relative to the total mass (100% by mass) of the polyisocyanate composition is preferably 0.03% by mass, more preferably 0.05% by mass, and even more preferably 0.08% by mass. By making the sulfur atom content above the above-mentioned lower limit, there is a tendency to exhibit better water dispersibility due to the decrease in interfacial tension.

[0235] Furthermore, from the viewpoint of coating properties, the upper limit of the sulfur atom content in the polyisocyanate composition is preferably 3.0% by mass, more preferably 2.5% by mass, and even more preferably 2.0% by mass relative to the total mass (100% by mass) of the polyisocyanate composition. By keeping the sulfur atom content below the above-mentioned upper limit, there is a tendency for the coating properties to become better due to the increased number of isocyanate groups used in crosslinking.

[0236] That is, in the polyisocyanate composition, the content of sulfur atoms relative to the total mass (100% by mass) of the polyisocyanate composition is preferably 0.03% by mass or more and 3.0% by mass or less, more preferably 0.05% by mass or more and 2.5% by mass or less, and even more preferably 0.08% by mass or more and 2.0% by mass or less.

[0237] As a method for controlling the sulfur atom content within the aforementioned range, it is not limited to the methods described below, but examples include adjusting the mixing ratio of the compound containing sulfonic acid groups to the polyisocyanate compound used as a raw material. Furthermore, the sulfur atom content can be determined using ion chromatography (IC).

[0238] As a method for reacting the raw material polyisocyanate compound with the above-mentioned anionic compound, although not limited to the following, a method can be listed, for example, a method for reacting the terminal isocyanate group of the polyisocyanate of the raw material polyisocyanate compound with the active hydrogen group of the above-mentioned anionic compound.

[0239] (Method for manufacturing sulfonamide salts)

[0240] In the case where the above-mentioned compound containing a sulfonic acid group forms a salt with the above-mentioned amine compound, that is, in the case of an amine salt of sulfonic acid, it is obtained by, for example, mixing the compound containing a sulfonic acid group with the amine compound and causing it to undergo a neutralization reaction.

[0241] The neutralization reaction can be carried out before reacting with the polyisocyanate compound. Alternatively, it can be carried out simultaneously with the reaction with the polyisocyanate compound. Alternatively, the amine compound can be added after the polyisocyanate compound has reacted with a compound containing a sulfonic acid group.

[0242] When the active hydrogen group is a hydroxyl group, the neutralization reaction is preferably carried out before reacting with the polyisocyanate compound. Furthermore, when the active hydrogen group is an amino group, the neutralization reaction is preferably carried out simultaneously with the reaction with the polyisocyanate compound, or after reacting the polyisocyanate compound with a sulfonic acid having an active hydrogen group, the amine compound is added.

[0243] Furthermore, when the active hydrogen group is hydroxyl, in this neutralization reaction, regarding the mixing ratio of the sulfonic acid with hydroxyl group to the amine compound, the molar ratio of the amine compound to the sulfonic acid with hydroxyl group (molar ratio of amine compound / sulfonic acid with hydroxyl group) is preferably 0.5 or more and 2.0 or less, more preferably 0.8 or more and 1.5 or less.

[0244] When the neutralization reaction is carried out in advance, the temperature and time are determined appropriately according to the progress of the reaction. The temperature is usually preferably above 0°C and below 100°C, and the mixing time is preferably above 10 minutes and below 24 hours.

[0245] The solvent used in preparing the amine salts of the compounds containing sulfonic acid groups described above is preferably water or a hydrophilic solvent. There are no particular limitations on the hydrophilic solvent; examples include alcohols, ether alcohols, ketones, and amide solvents. These solvents can be used alone or in combination.

[0246] Examples of alcohols include methanol, ethanol, propanol, butanol, and isopropanol.

[0247] 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, and dipropylene glycol monomethyl ether.

[0248] Examples of ketones include acetone, methyl ethyl ketone, and methyl isobutyl ketone.

[0249] Examples of amide solvents include N,N-dimethylformamide and N,N-dimethylacetamide.

[0250] After the neutralization reaction, it is preferable to remove water or a hydrophilic solvent.

[0251] (Catonic compounds)

[0252] The cationic compound is not particularly limited, and examples include amine compounds containing hydroxyl groups such as dimethylethanolamine, diethylethanolamine, diethanolamine, methyldiethanolamine, N,N-dimethylaminohexanol, N,N-dimethylaminoethoxyethanol, N,N-dimethylaminoethoxyethoxyethanol, N,N,N'-trimethylaminoethylethanolamine, and N-methyl-N-(dimethylaminopropyl)aminoethanol. Among these, dimethylethanolamine, diethylethanolamine, N,N-dimethylaminohexanol, N,N-dimethylaminoethoxyethanol, or N,N-dimethylaminoethoxyethoxyethanol are preferred. The tertiary amino group (cationic hydrophilic group) derived from the above cationic compounds and introduced into the polyisocyanate can also be quaternized using dimethyl sulfate, diethyl sulfate, etc.

[0253] The tertiary amino group of a cationic compound is preferably neutralized by a compound having an anionic group. This anionic group is not particularly limited, and examples include carboxyl, sulfonic acid, phosphate, halogen, and sulfate groups.

[0254] The compounds containing carboxyl groups mentioned above are not particularly limited, and examples include formic acid, acetic acid, propionic acid, butyric acid, and lactic acid.

[0255] The compounds containing sulfonic acid groups mentioned above are not particularly limited, and examples include ethanesulfonic acid, etc.

[0256] The compounds containing phosphate groups mentioned above are not particularly limited, and examples include phosphoric acid and acid phosphate esters.

[0257] The compounds containing halogen groups mentioned above are not particularly limited, and examples include hydrochloric acid.

[0258] The compounds containing a sulfuric acid group are not particularly limited, and examples include sulfuric acid. Among them, compounds containing a carboxyl group are preferred, and acetic acid, propionic acid, or butyric acid are more preferred.

[0259] From the viewpoint of coating properties, the content of structural units derived from ionic compounds relative to the total mass of the polyisocyanate composition, i.e., the mass fraction of ionic compounds bonded to ionic polyisocyanate compounds, is preferably 1.0% by mass or more and 40.0% by mass or less, more preferably 5.0% by mass or more and 15.0% by mass or less, even more preferably 10.0% by mass or more and 13.5% by mass or less, and particularly preferably 11.0% by mass or more and 13.0% by mass or less. By keeping the content of ionic compounds within the above range, there is a tendency for more isocyanate groups to be used for crosslinking, resulting in better coating properties (appearance, water resistance, and hardness).

[0260] The content of structural units derived from ionic compounds, expressed as the ionic compound-based modification rate of ionic polyisocyanate (A), can be determined using liquid chromatography-mass spectrometry (LC-MS) as described in the above mass ratio (a2) / (b2).

[0261] (Nonionic compounds)

[0262] As a nonionic compound, there are no particular limitations; examples include polyalkylene glycol alkyl ethers. From the viewpoint of reducing the viscosity of the polyisocyanate composition, the polyalkylene glycol alkyl ether preferably has one hydroxyl group.

[0263] Preferred polyalkylene glycol alkyl ethers have the structure shown in the following general formula (I).

[0264]

[0265] (In general formula (I), R) 11 R is an alkylene group having 1 or more but less than 4 carbon atoms. 12 It is an alkyl group with 1 or more but less than 4 carbon atoms, and n11 is 4.0 or more but less than 20.

[0266] Polyalkylene glycol alkyl ethers are not single components, but rather an aggregate of substances with varying degrees of polymerization (n) (hereafter sometimes referred to as "degree of polymerization n" or simply "n"). Therefore, the degree of polymerization n is expressed as its average value.

[0267] When polyisocyanates are mixed into aqueous base agents, thickening during mixing often becomes a problem. Excessive thickening prevents the polyisocyanates from dispersing evenly in the base agent, potentially leading to a decrease in the physical properties of the coating film.

[0268] Therefore, from the viewpoint of water dispersibility and dispersibility in the main agent, n is 4.0 or more and 20 or less, preferably 4.0 or more and 16 or less, and more preferably 4.0 or more and 12 or less. By making n above the above lower limit value, there is a tendency for improved dispersibility due to increased emulsifying power; on the other hand, by making n below the above upper limit value, there is a tendency for easy dispersion to prevent viscosity from increasing.

[0269] Polyalkylene glycol alkyl ethers can also be used in combination of two or more substances with different n values. The n value of polyalkylene glycol alkyl ethers can be determined using proton nuclear magnetic resonance (NMR).

[0270] In general formula (I), from the perspective of imparting hydrophilicity, R 11 R is an alkylene group with 1 or more but less than 4 carbon atoms, which, from the viewpoint of further imparting hydrophilicity, 11 Preferably, it is an ethylene with 2 carbon atoms.

[0271] Furthermore, from the perspective of imparting hydrophilicity, R 12 From the viewpoint that R is an alkyl group with 1 or more but less than 4 carbon atoms, it can further impart hydrophilicity. 12 The preferred methyl group is one carbon atom.

[0272] While not limited to the following, examples of polyalkylene glycol alkyl ethers include polyethylene glycol (mono) methyl ether, poly(ethylene, propylene) glycol (mono) methyl ether, and polyethylene glycol (mono) ethyl ether. Among these, polyethylene glycol (mono) methyl ether is preferred from the viewpoint of imparting hydrophilicity.

[0273] From the viewpoint of coating properties, the content of structural units derived from the nonionic compound (preferably a polyalkylene glycol alkyl ether), i.e., the mass fraction of the nonionic compound bonded to the nonionic polyisocyanate compound, relative to the total mass of the polyisocyanate composition, is preferably 0.1% by mass or more and 10.0% by mass or less, more preferably 0.3% by mass or more and 9.5% by mass or less, and even more preferably 0.5% by mass or more and 9.0% by mass or less. By keeping the content of the portion derived from the nonionic compound within the above range, there is a tendency for more isocyanate groups to be used for crosslinking, resulting in better coating properties (appearance, water resistance, and hardness).

[0274] The content of structural units derived from nonionic compounds, expressed as the modification rate of nonionic polyisocyanate (B) based on ionic compounds, can be determined using liquid chromatography-mass spectrometry (LC-MS) as described in the above mass ratio (a2) / (b2).

[0275] <Other Constituents>

[0276] The polyisocyanate composition of this embodiment may include other components in addition to ionic polyisocyanate compound (A) and nonionic polyisocyanate compound (B). These other components are not particularly limited and may include, for example, solvents, antioxidants, light stabilizers, polymerization inhibitors, surfactants, and super-antioxidants.

[0277] The solvent can be either hydrophilic or hydrophobic. These solvents can be used alone or in combination.

[0278] As a hydrophobic solvent, there are no particular limitations, but examples include mineral oil, solvent naphtha, LAWS (Low Aromatic White Spirit), HAWS (High Aromatic White Spirit), toluene, xylene, cyclohexane, esters, ketones, and amides.

[0279] Examples of esters include ethyl acetate and butyl acetate.

[0280] Examples of ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

[0281] Examples of amides include N,N-dimethylformamide and N,N-dimethylacetamide.

[0282] As a hydrophilic solvent, there are no particular limitations; examples include esters of alcohols, ethers, and ether alcohols.

[0283] Examples of alcohols include methanol, ethanol, propanol, isopropanol, and 2-ethylhexanol.

[0284] Examples of ethers include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, and dipropylene glycol dimethyl ether.

[0285] Examples of esters that are 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 dipropylene glycol monomethyl ether acetate.

[0286] In the polyisocyanate composition of this embodiment, from the viewpoint of ease of dispersion, the solvent content relative to the total mass of the polyisocyanate composition of this embodiment is preferably 0% by mass or more and 90% by mass or less, more preferably 0% by mass or more and 50% by mass or less, and even more preferably 0% by mass or more and 30% by mass or less.

[0287] Examples of antioxidants and light stabilizers include substances shown in (a) to (e) below. They may be present individually or in two or more forms.

[0288] (a) Aliphatic, aromatic or alkyl-substituted aromatic esters of phosphoric acid or phosphorous acid, and hypophosphoric acid derivatives.

[0289] (b) Phosphorus compounds such as phenylphosphonic acid, phenylphosphonic acid, diphenylphosphonic acid, polyphosphonates, dialkyl pentaerythritol diphosphite, and dialkyl bisphenol A diphosphite.

[0290] (c) Phenolic derivatives (especially hindered phenolic compounds).

[0291] (d) Sulfur-containing compounds such as thioether compounds, dithioester compounds, mercaptobenzimidazole compounds, symmetrical diphenylthiourea compounds, and thiodipropionates.

[0292] (e) Tin compounds such as tin maleate and dibutyltin monooxide.

[0293] Examples of polymerization inhibitors include hydroquinones, phenols, cresols, catechols, and benzoquinones. More specifically, examples include benzoquinone, p-benzoquinone, p-toluenequinone, p-xylenequinone, naphthoquinone, 2,6-dichloroquinone, hydroquinone, trimethylhydroquinone, catechol, p-tert-butylcatechol, 2,5-di-tert-butylhydroquinone, monomethylhydroquinone, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, and hydroquinone monomethyl ether. These can be present individually or in combination with two or more other compounds.

[0294] Examples of surfactants include, for instance, well-known anionic surfactants, cationic surfactants, and amphoteric surfactants.

[0295] In the polyisocyanate composition of this embodiment, the total content of antioxidant, light stabilizer, polymerization inhibitor and surfactant is preferably 0% by mass or more and 10% by mass or less relative to the total mass of the polyisocyanate composition of this embodiment, 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.

[0296] <Method for manufacturing polyisocyanate compositions>

[0297] The method for manufacturing the polyisocyanate composition of this embodiment can be exemplified by the following methods:

[0298] (1) A method for causing a portion of the isocyanate groups in a polyisocyanate compound to undergo an addition reaction with a nonionic compound and an ionic compound simultaneously or sequentially;

[0299] (2) A method for separately manufacturing nonionic polyisocyanate compound (A) and ionic polyisocyanate compound (B) and mixing them in a desired ratio;

[0300] (3) A method for separately manufacturing nonionic polyisocyanate compound (A), ionic polyisocyanate compound (B) and unmodified polyisocyanate compound (C) and mixing them in a desired ratio;

[0301] (4) When using diisocyanate as a raw material to manufacture polyisocyanate compounds, a method in which nonionic compounds and ionic compounds react simultaneously or sequentially;

[0302] (5) A method for separately manufacturing a nonionic polyisocyanate compound obtained by reacting a nonionic compound with a diisocyanate as a raw material and an ionic polyisocyanate compound obtained by reacting an ionic compound with a diisocyanate as a raw material, and mixing them in a desired ratio, etc.

[0303] Among the above manufacturing methods, from the viewpoint of ease of manufacturing and design, method (1), (2) or (3) is preferred, and method (2) is more preferred.

[0304] The reaction of polyisocyanate compounds with hydrophilic compounds can be catalyzed using organometallic salts, tertiary amine compounds, or alkali metal alkoxides. Examples of metals constituting the aforementioned organometallic salts include tin, zinc, and lead. Examples of alkali metals include sodium.

[0305] The reaction temperature between the polyisocyanate compound and the hydrophilic compound is preferably -20°C or higher and 150°C or lower, more preferably 30°C or higher and 130°C or lower. By setting the reaction temperature above the lower limit mentioned above, there is a tendency to further improve reactivity. Furthermore, by setting the reaction temperature below the upper limit mentioned above, there is a tendency to more effectively suppress side reactions.

[0306] Preferably, the hydrophilic compound reacts completely with the polyisocyanate without leaving any residue in an unreacted state. Because no hydrophilic compound remains, the water dispersibility of the polyisocyanate composition tends to improve, and the shelf life when used to formulate coating compositions becomes better.

[0307] When the hydrophilic compound is a sulfonic acid having hydroxyl groups, the method for manufacturing the polyisocyanate composition of this embodiment preferably includes, for example, a step (X) of mixing and reacting an amine salt of a sulfonic acid having hydroxyl groups with a polyisocyanate.

[0308] Alternatively, the method for manufacturing the polyisocyanate composition of this embodiment preferably includes, for example, a step (Y) of mixing a sulfonic acid having hydroxyl groups, a polyisocyanate, and an amine compound.

[0309] In step (X), it is preferable to add the amine salt of the sulfonic acid to the polyisocyanate after it has been prepared in advance. Alternatively, in step (Y), the sulfonic acid and amine compound having hydroxyl groups can be added to the polyisocyanate simultaneously, or they can be added sequentially.

[0310] Preferably, step (X) is used, and more preferably, the amine salt of sulfonic acid is added to the polyisocyanate after it has been prepared in advance.

[0311] When the hydrophilic compound is a sulfonic acid with hydroxyl groups, in the reaction between the polyisocyanate compound and the sulfonic acid with hydroxyl groups, from the viewpoint of shelf life and dispersibility, the mixing ratio of the sulfonic acid with hydroxyl groups or its amine salt to the polyisocyanate compound, in terms of the molar ratio of isocyanate group to hydroxyl group, is preferably in the range of 2 or more and 400 or less, more 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.

[0312] When the hydrophilic compound is a nonionic compound, in the reaction between the polyisocyanate compound and the nonionic compound, from the viewpoint of shelf life and gloss, the mixing ratio of the polyisocyanate compound and the nonionic compound is preferably 2.0% by mass or more and 50.0% by mass or less relative to 100.0% by mass of the polyisocyanate compound, more preferably 4.0% by mass or more and 40.0% by mass or less.

[0313] When the hydrophilic compound is a polyalkylene glycol alkyl ether, in the reaction between the polyisocyanate compound and the polyalkylene glycol alkyl ether, the mixing ratio of the polyisocyanate compound to the polyalkylene glycol alkyl ether, from the viewpoint of shelf life and gloss, is preferably in the range of 2 or more and 400 or less, more 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, based on the molar ratio of isocyanate group to hydroxyl group.

[0314] In the reaction of polyisocyanate compounds with hydrophilic compounds, the reaction temperature and reaction time are appropriately determined according to the progress of the reaction. The reaction temperature is preferably above 0°C and below 150°C, and the reaction time is preferably above 30 minutes and below 48 hours.

[0315] Furthermore, in the reaction of polyisocyanate compounds with hydrophilic compounds, known and commonly used catalysts can be used as appropriate. There are no particular limitations on the catalysts used, and examples include substances shown in (a) to (f) below. They can be used alone or in combination.

[0316] (a) Organotin compounds such as tin octanoate, tin 2-ethyl-1-hexanoate, tin ethylhexanoate, tin laurate, tin palmitate, dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dimaleate, dibutyltin dilaurate, dioctyltin diacetate, and dioctyltin dilaurate.

[0317] (b) Organic zinc compounds such as zinc chloride, zinc octanoate, zinc 2-ethyl-1-hexanoate, zinc 2-ethylhexanoate, zinc stearate, zinc naphthenate, and zinc acetylacetonate;

[0318] (c) Organotitanium compounds;

[0319] (d) Organozirconium compounds;

[0320] (e) Tertiary amines such as triethylamine, tributylamine, N,N-diisopropylethylamine, and N,N-dimethylethanolamine;

[0321] (f) Diamines such as triethylenediamine, tetramethylethylenediamine, and 1,4-diazabicyclo[2.2.2]octane.

[0322] In the method for manufacturing the polyisocyanate composition of this embodiment, a solvent may or may not be used. The solvent used in the method for manufacturing the polyisocyanate composition of this embodiment may be a hydrophilic solvent or a hydrophobic solvent. As hydrophilic and hydrophobic solvents, the same solvents exemplified in the other constituent components described above can be listed.

[0323] Furthermore, in the method for manufacturing the polyisocyanate composition of this embodiment, at least one substance selected from the group consisting of antioxidants, light stabilizers, polymerization inhibitors, and surfactants may be added in addition to the addition of a hydrophilic polyisocyanate compound. As antioxidants, light stabilizers, polymerization inhibitors, and surfactants, substances identical to those exemplified in the other constituent components described above may be included.

[0324] <Characteristics of Polyisocyanate Compositions>

[0325] From the viewpoint of ease of mixing of coatings, the viscosity of the polyisocyanate composition at 25°C is preferably 100 mPa·s or more and 10000 mPa·s or less, more preferably 500 mPa·s or more and 7000 mPa·s or less, and even more preferably 1000 mPa·s or more and 5000 mPa·s or less.

[0326] With the non-volatile component set at 100% by mass, from the viewpoint of solvent resistance of the coating film, the isocyanate group content of the polyisocyanate composition of this embodiment is preferably 10.0% by mass or more and 25.0% by mass or less, more preferably 15.0% by mass or more and 21.0% by mass or less. There are no particular limitations on the method for controlling the isocyanate group content to the aforementioned range; for example, methods for adjusting the mixing ratio of the hydrophilic compound and the polyisocyanate compound can be cited.

[0327] It should be noted that, in this embodiment, the viscosity and isocyanate group content can be determined using the methods described in the examples below.

[0328] <Sealing off>

[0329] The polyisocyanate composition of this embodiment may contain a capped polyisocyanate that has been capped by reacting the isocyanate groups in the polyisocyanate with a thermally dissociative capping agent. That is, in this case, the polyisocyanate composition of this embodiment may also be referred to as a capped polyisocyanate composition.

[0330] End-capping can be performed on both ionic polyisocyanate compound (A) and nonionic polyisocyanate compound (B), or on either ionic polyisocyanate compound (A) or nonionic polyisocyanate compound (B). Preferably, both ionic polyisocyanate compound (A) and nonionic polyisocyanate compound (B) are end-capped.

[0331] The end-capping of the ionic polyisocyanate compound (A) and / or the nonionic polyisocyanate compound (B) can be complete or partial. In the case of partial capping, the end-capping rate is preferably 10 mol% or more and less than 100 mol% relative to the total molar amount of isocyanate groups.

[0332] [Thermally dissociable capping agent]

[0333] End-capped polyisocyanates are obtained by end-capping at least a portion of the isocyanate groups using a thermally dissociable end-capping agent.

[0334] Thermally dissociative end-capping agents are compounds with one active hydrogen atom in their molecules, possessing the property of dissociating from the isocyanate group upon heating. Examples of thermally dissociative end-capping agents include, for instance, alcohol compounds, alkylphenol compounds, phenol compounds, active methylene compounds, thiol compounds, acid amide compounds, acid imide compounds, imidazole compounds, urea compounds, oxime compounds, amine compounds, imine compounds, and pyrazole compounds.

[0335] More specifically, examples of thermally dissociable end-capping agents include compounds shown in (1) to (13) below. These end-capping agents can be used alone or in combination of two or more.

[0336] (1) Alcohols: methanol, ethanol, 2-propanol, n-butanol, sec-butanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol.

[0337] (2) Alkylphenol compounds: Monoalkylphenols or dialkylphenols with alkyl groups having 4 or more carbon atoms as substituents. For example, monoalkylphenols such as n-propylphenol, isopropylphenol, n-butylphenol, sec-butylphenol, tert-butylphenol, n-hexylphenol, 2-ethylhexylphenol, n-octylphenol, and n-nonylphenol; and dialkylphenols such as di-n-propylphenol, diisopropylphenol, isopropylcresol, di-n-butylphenol, di-tert-butylphenol, di-sec-butylphenol, di-n-octylphenol, di-2-ethylhexylphenol, and di-n-nonylphenol.

[0338] (3) Phenolic compounds: phenol, cresol, ethylphenol, stylated phenol, hydroxybenzoate.

[0339] (4) Active methylene compounds: dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone.

[0340] (5) Thiol compounds: Butylthiol, dodecylthiol.

[0341] (6) Acid amide compounds: acetylaniline, acetamide, ε-caprolactam, δ-valerolactam, γ-butyrolactam.

[0342] (7) Acid imide compounds: succinimide, maleimide.

[0343] (8) Imidazole compounds: imidazole, 2-methylimidazolium.

[0344] (9) Urea compounds: urea, thiourea, ethylene urea.

[0345] (10) Oxime compounds: formaldehyde oxime, acetaldehyde oxime, acetone oxime, methyl ethyl ketone oxime, cyclohexanone oxime.

[0346] (11) Amine compounds: diphenylamine, aniline, carbazole, di-n-propylamine, diisopropylamine, isopropyl ethylamine.

[0347] (12) Imine compounds: ethyleneimine, polyethyleneimine.

[0348] (13) Pyrazole compounds: pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole.

[0349] The thermally dissociative capping agent preferably includes at least one of the following groups: oxime compounds, pyrazole compounds, active methylene compounds, amine compounds, and acid amide compounds. From the viewpoint of storage stability when preparing a coating containing an amphiphilic solvent, it is more preferably a pyrazole compound or an oxime compound.

[0350] <Preparation method of capped polyisocyanates>

[0351] There are no particular limitations on the terminated polyisocyanate; for example, it can be obtained by reacting the aforementioned polyisocyanate, the aforementioned hydrophilic compound, and the aforementioned thermally dissociable terminator.

[0352] The reaction of the isocyanate group of the polyisocyanate with the active hydrogen group of the aforementioned hydrophilic compound, and the reaction of the isocyanate group of the polyisocyanate with the thermally dissociable end-capping agent, can be carried out simultaneously, or either reaction can be carried out first, followed by the second reaction. Preferably, the reaction of the isocyanate group with the active hydrogen group of the hydrophilic compound is carried out first to obtain a polyisocyanate having structural units derived from the hydrophilic compound, followed by the reaction with the thermally dissociable end-capping agent.

[0353] In the reaction process, catalysts such as organometallic salts of tin, zinc, and lead; tertiary amine compounds; and alkali metal alkoxides such as sodium can be used.

[0354] The reaction temperature of the reaction process is preferably -20°C or higher and 150°C or lower, more preferably 30°C or higher and 100°C or lower. By setting the reaction temperature above the lower limit, there is a tendency to further improve reactivity. Furthermore, by setting the reaction temperature below the upper limit, there is a tendency to further suppress side reactions.

[0355] Preferably, the hydrophilic compound reacts completely with the polyisocyanate without remaining in an unreacted state. Because it does not remain in an unreacted state, there is a tendency to further suppress the decrease in the water dispersion stability of the capped polyisocyanate and further suppress the decrease in curability when used as a coating composition.

[0356] Coating Compositions

[0357] The coating composition of this embodiment comprises the above-described polyisocyanate composition and a resin.

[0358] The coating composition of this embodiment, by including the above-described polyisocyanate composition, produces a coating film with excellent appearance, water resistance, and hardness.

[0359] The coating composition of this embodiment can also be used in the form of an organic solvent-based coating composition, but it is preferred to use it in the form of an aqueous coating composition obtained by dissolving or dispersing the above-mentioned polyisocyanate composition and the resin as a film-forming component in a water-based medium. In particular, it can also be used in architectural coatings, automotive coatings, automotive repair coatings, plastic coatings, adhesives, bonding agents, building materials, household water-based coatings, other coating agents, sealants, inks, casting molding materials, elastomers, foams, plastic raw materials, and fiber treatment agents.

[0360] <Resins>

[0361] The type of resin used as the main agent is not particularly limited, but can be listed as follows: acrylic resin, polyester resin, polyether resin, epoxy resin, fluororesin, polyurethane resin, polyvinylidene chloride copolymer, polyvinyl chloride copolymer, vinyl acetate copolymer, acrylonitrile butadiene copolymer, polybutadiene copolymer, styrene butadiene copolymer, etc.

[0362] Among them, acrylic resins, polyester resins, or polyether resins are preferred as resins.

[0363] [Acrylic resins]

[0364] As for acrylic resins, there are no particular limitations, and examples include acrylic resins obtained by polymerizing individual or mixed polymerizable monomers selected from (a) to (e) below. These acrylic resins can be used alone or in combination.

[0365] (a) Methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, and other methacrylates.

[0366] (b) Methacrylates containing active hydrogen, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, and 4-hydroxybutyl methacrylate.

[0367] (c) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid.

[0368] (d) Unsaturated amides such as acrylamide, N-hydroxymethylacrylamide, and diacetone acrylamide.

[0369] (e) Glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, dibutyl fumarate, p-styrene sulfonic acid, allyl sulfosuccinic acid and other polymeric monomers.

[0370] The polymerization method for these monomers is usually emulsion polymerization, but they can also be produced through suspension polymerization, dispersion polymerization, and solution polymerization. In emulsion polymerization, polymerization can also be carried out in stages.

[0371] [Polyester Resin]

[0372] As for polyester resins, there are no particular limitations, and examples include polyester resins obtained by condensation reaction of a single carboxylic acid or a mixture with a single polyol or a mixture thereof.

[0373] Examples of the aforementioned carboxylic acids include succinic acid, adipic acid, sebacic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid.

[0374] Examples of polyols mentioned above include diols, triols, and tetraols.

[0375] Examples of glycols 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, and 2,2-diethyl-1,3-propanediol.

[0376] Examples of triols include glycerol and trimethylolpropane.

[0377] Examples of tetraols include diglycerides, dimethylolpropane, and pentaerythritol.

[0378] Alternatively, polycaprolactones, such as those obtained by hydroxyl ring-opening polymerization of ε-caprolactone from low molecular weight polyols, can also be used as polyester resins.

[0379] [Polyether resins]

[0380] Examples of polyether resins include substances shown in (a) to (d) below.

[0381] (a) Polyether polyols obtained by adding a single or mixture of polyhydroxy compounds to a single or mixture of epoxides using a strongly basic catalyst.

[0382] (b) Polyether polyols obtained by reacting epoxides with polyamine compounds.

[0383] (c) Polyether polyols obtained by ring-opening polymerization of cyclic ethers.

[0384] (d) Polymer polyols obtained by polymerizing acrylamide and the like using the polyether polyols obtained in (a) to (c) as a medium.

[0385] Examples of the polyhydroxy compounds in (a) include, for example, the compounds shown in (i) to (vi) below.

[0386] (i) diglycerides, di(trimethylolpropane), pentaerythritol, dipentaerythritol, etc.;

[0387] (ii) Sugar alcohols such as erythritol, D-threitol, L-arabinitol, ribitol, xylitol, sorbitol, mannitol, galactitol, and rhamnitol;

[0388] (iii) Monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbitol, rhamnose, fucose, and deoxyribose;

[0389] (iv) Disaccharides such as trehalose, sucrose, maltose, cellulosic disaccharide, gentiobiose, lactose, and melibiose;

[0390] (v) Trisaccharides such as melitriose, gentiotriose, and pinotriose;

[0391] (vi) Stachyose and other four sugars.

[0392] Examples of strongly basic catalysts as described in (a) include, for example, alkali metal hydroxides, alkoxides, and alkylamines. Examples of alkali metals include, for example, lithium, sodium, and potassium.

[0393] Examples of epoxides in (a) include ethylene oxide, propylene oxide, butane oxide, cyclohexane oxide, and phenylene oxide.

[0394] Examples of polyamine compounds in (b) include ethylenediamines.

[0395] Examples of cyclic ethers in (c) include tetrahydrofuran.

[0396] Furthermore, in the coating composition of this embodiment, these resins can be combined as needed, such as melamine-based curing agents, urethane dispersions, and urethane acrylic emulsions.

[0397] Furthermore, these resins are preferably emulsified, dispersed, or dissolved in water. Therefore, the carboxyl groups, sulfonic acid groups, etc., contained in the resins can be neutralized.

[0398] As a neutralizing agent used to neutralize carboxyl groups, sulfonic acid groups, etc., there are no particular limitations, and examples include ammonia, water-soluble amino compounds, etc.

[0399] Examples of water-soluble amino compounds include monoethanolamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, dipropylamine, isopropylamine, diisopropylamine, triethanolamine, butylamine, dibutylamine, 2-ethylhexylamine, ethylenediamine, propylenediamine, methylethanolamine, dimethylethanolamine, diethylethanolamine, and morpholine. They can be used alone or in combination of two or more.

[0400] The neutralizing agent is preferably a tertiary amine, more preferably triethylamine or dimethylethanolamine.

[0401] <Other Ingredients>

[0402] In addition to the polyisocyanate composition and resin described above, the coating composition of this embodiment may further include additives typically added to coatings. Examples of such additives include, for instance, inorganic pigments, organic pigments, extender pigments, silane coupling agents, titanium coupling agents, organophosphates, organophosphites, thickeners, leveling agents, thixotropic agents, defoamers, freeze stabilizers, matting agents, crosslinking reaction catalysts (curing accelerators), anti-skinning agents, dispersants, wetting agents, fillers, plasticizers, lubricants, reducing agents, preservatives, mildew inhibitors, deodorizers, anti-yellowing agents, ultraviolet absorbers, antistatic agents or static electricity regulators, and anti-settling agents. These additives may be included individually or in combination of two or more.

[0403] As a crosslinking reaction catalyst (curing promotion catalyst), it is not limited to the following examples, but can include catalysts such as those shown in (a) or (b) below.

[0404] (a) Metal salts such as dibutyltin dilaurate, tin 2-ethylhexanoate, zinc 2-ethylhexanoate, and cobalt salts.

[0405] (b) Tertiary amines such as triethylamine, pyridine, methylpyridine, benzyl dimethylamine, N,N-dimethylcyclohexylamine, N-methylpiperidine, pentamethyldiethylenetriamine, N,N'-endo-Ethylenepiperazine, and N,N'-dimethylpiperazine.

[0406] To improve dispersibility in coatings, the coating composition of this embodiment may further include surfactants in addition to the above-described polyisocyanate composition and resins.

[0407] To improve the preservation stability of the coating, the coating composition of this embodiment may further include antioxidants, light stabilizers, and polymerization inhibitors in addition to the above-mentioned polyisocyanate composition and resin.

[0408] <Method for manufacturing the coating composition>

[0409] The coating composition of this embodiment is obtained by mixing the above-mentioned polyisocyanate composition and resin with other components as needed using a known method.

[0410] For example, in the case of a water-based coating composition, additives exemplified above are added to the resin or its aqueous dispersion or water-soluble form as needed. Next, the above-mentioned polyisocyanate composition or its aqueous dispersion is added as a curing agent, and water and solvent are further added as needed to adjust the viscosity. Then, by forcibly stirring using a mixer, a water-based coating composition can be obtained.

[0411] In the case of manufacturing a solvent-based coating composition, firstly, additives exemplified among the other components are added to the resin or its solvent dilution as needed. Next, the aforementioned polyisocyanate composition is added as a curing agent, and solvent is further added to adjust the viscosity as needed. Then, the solvent-based coating composition is obtained by manual stirring or stirring using a mixer such as a Mazela.

[0412] Coated Substrates

[0413] The coating substrate in this embodiment is a coating substrate coated with the above-described coating composition. Preferably, the coating substrate in this embodiment has a coating layer comprising the above-described coating composition.

[0414] The coating substrate of this embodiment has a coating film formed by curing the above-described coating composition, and therefore has excellent appearance, water resistance and hardness.

[0415] The coating substrate of this embodiment is obtained by applying the above-mentioned coating composition onto the substrate using known methods such as roller coating, curtain coating, spray coating, rotary cup coating, and electrostatic coating, and then curing it by a process of room temperature drying or sintering.

[0416] The coating substrate of this embodiment can have a desired substrate, and may have a conventional primer before coating, depending on the circumstances.

[0417] Examples of such substrates include metals, wood, glass, stone, ceramic materials, concrete, rigid and flexible plastics, fiber products, leather products, and paper.

[0418] Example

[0419] The present invention is described below with examples and comparative examples to illustrate the invention in more detail, but the invention is not limited to the following examples as long as it does not deviate from its spirit.

[0420] The physical properties and evaluation of the polyisocyanate compositions in the Examples and Comparative Examples were determined as follows. It should be noted that, unless otherwise specified, "parts" and "%" refer to "parts by mass" and "% by mass".

[0421] <Determination Method>

[0422] [Physical properties 1]

[0423] (Viscosity)

[0424] Viscosity was measured using an E-type viscometer (TOKIMEC) at 25°C. A standard rotor (1°34'×R) was used. 2 4). The rotational speed is shown below.

[0425] (Rotation speed)

[0426] 100 r.pm (for cases where the pressure is less than 128 mPa·s)

[0427] 50 r.pm (for conditions above 128 mPa·s and below 256 mPa·s)

[0428] 20 r.pm (for conditions above 256 mPa·s and below 640 mPa·s)

[0429] 10 r.pm (for conditions above 640 mPa·s and below 1280 mPa·s)

[0430] 5r.pm (for conditions above 1280mPa·s and below 2560mPa·s)

[0431] 2.5 rpm (for speeds above 2560 mPa·s and below 5120 mPa·s)

[0432] [Physical Properties 2]

[0433] (Isocyanate group content (NCO%))

[0434] The polyisocyanate compound obtained in the synthesis example, as well as the polyisocyanate compositions obtained in the examples and comparative examples, were used as samples. The isocyanate group content was determined according to the method described in JIS K7301-1995 (Test method for toluene diisocyanate type prepolymers for thermosetting urethane elastomers). A more specific method for determining the isocyanate group content (NCO%) is shown below.

[0435] (1) Take 1g (Wg) of the sample into a 200mL conical flask, add 20mL of toluene to the flask to dissolve the sample.

[0436] (2) Subsequently, add 20 mL of 2.0 N di-n-butylamine-toluene solution to the above flask and let stand for 15 minutes.

[0437] (3) Add 70 mL of 2-propanol to the above flask to dissolve it and obtain a solution.

[0438] (4) For the solution obtained in (3) above, titrate with 1 mol / L hydrochloric acid to determine the sample titration amount (V1 mL).

[0439] (5) Without adding a sample, the same method as (1) to (3) above is used to determine the blank titration amount (V0mL).

[0440] The isocyanate group content (NCO%) can be calculated from the sample titration and blank titration obtained above using the formula shown below.

[0441] Isocyanate group content (mass%) = (V0-V1)×42 / [W(1g)×1000]×100

[0442] [Physical Properties 3]

[0443] (mass ratio (A) / (B) and mass ratio (a2) / (b2))

[0444] The mass ratio (A) / (B) of ionic polyisocyanate compound (A) to nonionic polyisocyanate compound (B), and the mass ratio (a2) / (b2) of structural units (a2) derived from ionic compounds in ionic polyisocyanate compound (A) to structural units (b2) derived from nonionic compounds in nonionic polyisocyanate compound (B) were determined by liquid chromatography-mass spectrometry (LC-MS).

[0445] Specifically, using a polyisocyanate composition as a sample, the modification rate of ionic polyisocyanate (A) based on ionic compounds and the modification rate of nonionic polyisocyanate (B) based on nonionic compounds were calculated based on the peak area ratio of ionic polyisocyanate (A), nonionic polyisocyanate (B), and unmodified polyisocyanate compound at 220 nm using liquid chromatography (LC). Then, using the obtained modification rates, the content of ionic polyisocyanate (A) and nonionic polyisocyanate (B) was calculated, thereby determining the mass ratio (A) / (B). Furthermore, the ratio of the modification rate of ionic polyisocyanate (A) based on ionic compounds to the modification rate of nonionic polyisocyanate (B) based on nonionic compounds was denoted as the mass ratio (a2) / (b2). Furthermore, the modification rate of ionic polyisocyanate (A) based on ionic compounds and the modification rate of nonionic polyisocyanate (B) based on nonionic compounds are recorded in the table below as the content of structural units derived from ionic compounds and the content of structural units derived from nonionic compounds, respectively.

[0446] The LC-based determination conditions for nonionic polyisocyanate (B) and unmodified polyisocyanate compounds are as follows.

[0447] (Measurement conditions)

[0448] LC device: Waters Corporation, UPLC (trade name)

[0449] Column: Waters Corporation, ACQUITY UPLC HSS T3 1.8μm C18, inner diameter 2.1mm × length 50mm

[0450] Flow rate: 0.3 mL / min

[0451] Mobile phase: A = 10 mM ammonium acetate aqueous solution, B = acetonitrile

[0452] Gradient conditions: The initial mobile phase composition is A / B = 98 / 2 (volume ratio). After the sample is injected, the ratio of B increases linearly, and after 10 minutes, A / B = 0 / 100 (volume ratio) is achieved.

[0453] Detection method: photodiode array detector, measurement wavelength 220nm

[0454] Ionic polyisocyanates (A) were determined by adding the following conditions to the above determination conditions.

[0455] (Additional measurement conditions)

[0456] Ionization modes: electrospray ionization, positive and negative ion detection

[0457] Scan range: m / z 100~2000

[0458] [Physical property 5]

[0459] (The content of each of the above structures derived from the isocyanate group in the polyisocyanate composition)

[0460] The obtained polyisocyanate composition was tested using Biospin Avance 600 (trade name) manufactured by Bruker. 13 C-NMR determination. Specific determination conditions are shown below.

[0461] (Measurement conditions)

[0462] 13 C-NMR apparatus: AVANCE 600 (manufactured by Bruker)

[0463] CryoProbe (manufactured by Bruker)

[0464] CryoProbe (registered trademark)

[0465] CPDUL

[0466] 600S3-C / HD-05Z

[0467] Resonant frequency: 150MHz

[0468] Concentration: 60 wt / vol%

[0469] Displacement reference: CDCl3 (77ppm)

[0470] Total number of times: 10,000

[0471] Pulse program: zgpg30 (complete proton decoupling, waiting time 2 seconds)

[0472] The mole fraction of each group relative to the total (100 mol%) of isocyanurate, iminooxadiazine dione, ureacarbate, and urea dione groups is determined by dividing the integral value of the following signals by the measured number of carbon atoms. Using the obtained mole fractions, the total content of urea dione and urea carbamate groups relative to the total molar amount of isocyanurate, iminooxadiazine dione, urea dione, and urea carbamate groups, as well as the molar ratio of urea dione to urea carbamate groups (urea dione / urea carbamate molar ratio) are calculated.

[0473] Isocyanurate group: (integral value around 148.6 ppm) ÷ 3

[0474] Iminooxadiazine diketoyl: (Integral value around 135.5 ppm) ÷ 1

[0475] Urea carbamate group: (integral value around 154ppm) ÷ 1

[0476] Ureadione structure: (Integral value around 157 ppm) ÷ 2

[0477] <Evaluation Methods>

[0478] [Rating 1]

[0479] (Water dispersibility of the polyisocyanate composition)

[0480] The water dispersibility was evaluated using the polyisocyanate compositions obtained in the Examples and Comparative Examples as samples, and the methods shown below were employed.

[0481] (1) Determine the mass (W0g) of a 100mL flask and Yoshino paper.

[0482] (2) Take the polyisocyanate composition into a 100 mL flask in such a way that the solid content is converted to 16 g (W2 g), and add 24 g of deionized water.

[0483] (3) Using a propeller blade, stir the solution in the 100mL flask at 200rpm for 3 minutes, and then filter it with the Yoshino paper weighed in (1).

[0484] (4) Combine the filter residue remaining in the Yoshino paper and the residue remaining in the 100mL flask, heat them in a dryer at 105°C for 1 hour, and calculate the mass (g) (W1g).

[0485] (5) Use the following formula to determine the proportion of the polyisocyanate composition dispersed in water. It should be noted that in the formula, Y is the non-volatile component (mass %).

[0486] "Percentage dispersed in water (mass%)"

[0487] ={1-(W2(g)-W0(g)) / (W2(16g)×Y)}×100

[0488] (6) Next, evaluate the water dispersibility according to the following evaluation criteria.

[0489] (Evaluation Criteria)

[0490] ○: 90% or more in quality

[0491] △: 80% or more by mass and less than 90% by mass

[0492] ×: Less than 80% by mass

[0493] [Preparation of the coating composition]

[0494] 40 g of an acrylic polyol aqueous dispersion (manufactured by Covestro, product name "BAYHYDROL A2470", hydroxyl value per unit resin: 128.7 mg KOH / g) was measured into a container. Next, each (terminated) polyisocyanate composition was added such that the molar ratio of isocyanate groups to the molar ratio of hydroxyl groups in the acrylic polyol aqueous dispersion (NCO / OH) of the polyisocyanate compositions obtained in Examples 1-19 and Comparative Examples 1-5, and the end-capped polyisocyanate compositions obtained in Examples 20 and 21, was 1.5. Then, deionized water was added so that the solid content of the coating composition was 42% by mass, and the mixture was stirred at 600 rpm for 10 minutes using a propeller blade to obtain each coating composition. The prepared coating compositions were evaluated as follows.

[0495] [Rating 2]

[0496] (Validity period)

[0497] The concentration change of isocyanate groups in the coating composition was calculated as follows: using an FT / IR sensor manufactured by Nippon Spectrophotometer Co., Ltd. 4 Infrared absorption spectroscopy measurements were performed using 200typeA (trade name) (detector: TGS, number of cycles: 16, resolution: 4 cm⁻¹). -1 In the study, based on the absorption peak of isocyanate (wavenumber 2271 cm⁻¹),-1 The absorption peak (wavenumber 1686 cm⁻¹) relative to isocyanurate is near. -1 The intensity ratio (nearby) is calculated. Setting the time immediately after coating the composition to 0 hours, the peak intensity of isocyanate at this time / the peak intensity of isocyanurate = X0. The peak intensity ratio after n hours is calculated as Xn, and the "isocyanate group retention rate" is calculated as Xn / X0. The shelf life is evaluated according to the following criteria, based on the time it takes for the isocyanate group retention rate to remain above 80%.

[0498] (Evaluation Criteria)

[0499] ○: 4 hours or more

[0500] △: More than 2 hours but less than 4 hours

[0501] ×: Less than 2 hours

[0502] [Rating 3]

[0503] (Appearance of the coating)

[0504] Using each coating composition, a 40 μm thick coating film was applied to a white board. It was then dried at 23°C and 50% humidity. After drying overnight, the resulting coating film was measured at 60 degrees using a gloss meter (Suga Test Instruments UDV-6P digital variable angle gloss meter, trade name) under JIS Z8741 conditions. The appearance was evaluated according to the following evaluation criteria.

[0505] (Evaluation Criteria)

[0506] ○: Gloss level of 60 degrees is 92% or higher

[0507] △: A gloss level of 60 degrees is 85% or higher but less than 92%.

[0508] ×: Gloss value of 60 degrees is less than 85%.

[0509] [Rating 4]

[0510] (Water resistance of the coating 1)

[0511] Using each coating composition, an applicator was applied to a glass plate to a thickness of 40 μm. The coating was then dried for 7 days at 23°C and 50% humidity to obtain a coating film. Next, a 20 mm diameter silicone O-ring was placed on the resulting coating film, and 0.5 g of water was injected into it. The film was then placed at 23°C for 24 hours, and the condition of the coating film after removing residual water was observed. The water resistance of the coating film was evaluated according to the following evaluation criteria. Samples with an "×" mark in "Evaluation 3" above could not be visually evaluated and were therefore marked as unmeasurable. It should be noted that, regarding the evaluation criteria, "bubbling" refers to the formation of water bubbles and expansion on the coating film surface.

[0512] (Evaluation Criteria)

[0513] ○: No change

[0514] △: Decreased gloss

[0515] ×: Foaming, cloudiness, or dissolution of the coating may occur.

[0516] [Rating 5]

[0517] (Water resistance of the coating 2)

[0518] Using each coating composition, an applicator was used to coat a polypropylene (PP) sheet with a thickness of 40 μm. The coating was then dried for 7 days at 23°C and 50% humidity to obtain a coating film. Approximately 0.2 g of the coating film was then cut using a cutter and placed in distilled water at 40°C. After 24 hours, the coating film was removed from the distilled water at 40°C, and its condition was observed after removing residual water from the surface. The water resistance of the coating film was evaluated according to the following evaluation criteria. Samples with an "×" mark in "Evaluation 3" above could not be visually evaluated and were therefore marked as unmeasurable.

[0519] (Evaluation Criteria)

[0520] ○: No change

[0521] △: A small number of bubbles are produced.

[0522] ×: Produces a large number of bubbles or causes the coating to dissolve.

[0523] [Rating 6]

[0524] (Coating hardness)

[0525] Using various coating compositions, a 40 μm thick coating was applied to a glass plate. The plate was then dried at 23°C and 50% humidity. After 7 days, the hardness of the resulting coating was measured using a König hardness tester (BYK Garder, trade name "Pendulumhardness tester"). The hardness of the coating was evaluated according to the following criteria.

[0526] (Evaluation Criteria)

[0527] ○: 130 times or more

[0528] △: 110 times or more but less than 130 times

[0529] ×: Less than 110 times

[0530] Synthesis of sulfonamide salts

[0531] [Synthesis Example 1-1]

[0532] (Synthesis of HES / TBA)

[0533] At room temperature (around 23°C), 10 parts by mass of 1-propanol were added to 20 parts by mass of a 70% by mass aqueous solution of 2-hydroxyethanesulfonic acid (hereinafter sometimes abbreviated as "HES"), and the mixture was stirred to obtain a solution. Then, tributylamine (hereinafter sometimes abbreviated as "TBA") was added dropwise to the stirred solution in a molar equivalent ratio to HES of 1, and diluted with the same amount of 1-propanol to obtain a liquid. One hour after the initial addition, stirring was stopped, and the solution was dehydrated and desolventized using an evaporator to obtain a 99.8% by mass tributylamine 2-hydroxyethanesulfonic acid salt (hereinafter sometimes abbreviated as "HES / TBA").

[0534] [Synthesis Example 1-2]

[0535] (Synthesis of HPS / TBA)

[0536] HES was replaced with 2-hydroxypropanesulfonic acid (HPS), and otherwise the same method as in Synthesis Example 1-1 above was used to obtain 2-hydroxypropanesulfonic acid tributylamine salt (hereinafter sometimes abbreviated as "HPS / TBA").

[0537] [Synthesis Example 1-3]

[0538] (Synthesis of HES / DMCHA)

[0539] Dimethylcyclohexylamine (hereinafter sometimes abbreviated as "DMCHA") was used instead of TBA, and otherwise the same method as in Synthesis Example 1-1 was used to obtain 99.8% by mass of 2-hydroxyethanesulfonate dimethylcyclohexylamine salt (hereinafter sometimes abbreviated as "HES / DMCHA").

[0540] [Synthesis Example 1-4]

[0541] (Synthesis of a mixture of HES / TBA and HES / DMCHA)

[0542] At room temperature (around 23°C), 10 parts by mass of 1-propanol were added to 20 parts by mass of a 70% by mass aqueous solution of 2-hydroxyethanesulfonic acid (hereinafter sometimes abbreviated as "HES"), and the mixture was stirred to obtain a solution. Then, tributylamine (hereinafter sometimes abbreviated as "TBA") and dimethylcyclohexylamine (hereinafter sometimes abbreviated as "DMCHA") were measured at a molar equivalent ratio to HES of 0.5, and diluted with 15 parts by mass of 1-propanol. Next, the diluted TBA and DMCHA solutions were added dropwise to the stirred HES solution. After one hour from the start of the addition, stirring was stopped, and the water and 1-propanol of the solvent were removed using an evaporator to obtain a mixture of HES / TBA and HES / DMCHA with a solid content of 99.8% by mass.

[0543] Synthesis of Polyisocyanates

[0544] [Synthesis example 2-1]

[0545] (Synthesis of polyisocyanate P-1)

[0546] A nitrogen atmosphere was created in a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen inlet tube, and dropping funnel. 1000 g of HDI and 4.0 g of isobutanol were added, and the temperature inside the reactor was maintained at 70°C with stirring. Tetramethyldecanoate ammonium was added, and phosphoric acid was added when the yield reached 40% by mass to stop the reaction. The reaction solution was then filtered, and unreacted HDI was removed using a thin-film evaporator to obtain polyisocyanate P-1. The obtained polyisocyanate P-1 had a viscosity of 2700 mPa·s at 25°C and an isocyanate group content of 21.7% by mass.

[0547] [Synthesis example 2-2]

[0548] (Synthesis of polyisocyanate P-2)

[0549] A nitrogen atmosphere was created in a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen inlet tube, and dropping funnel. 1000 g of HDI and 4.0 g of isobutanol were added, and the temperature inside the reactor was maintained at 70°C with stirring. Tetramethyldecanoate ammonium was added, and phosphoric acid was added when the yield reached 16% by mass to stop the reaction. The temperature was then raised to 160°C and maintained for 1 hour. After filtering the reaction solution, unreacted HDI was removed using a thin-film evaporator to obtain polyisocyanate P-2. The obtained polyisocyanate P-2 had a viscosity of 500 mPa·s at 25°C and an isocyanate group content of 23.3% by mass.

[0550] [Synthesis example 2-3]

[0551] (Synthesis of polyisocyanate P-3)

[0552] A nitrogen atmosphere was created in a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen inlet tube, and dropping funnel. 6,000 parts by mass of HDI were added, and the reactor temperature was maintained at 60°C for 2 hours with stirring. Subsequently, 80 parts by mass of tri-n-butylphosphine (Cytop, product name) was added as a catalyst for isocyanurate and ureidodiketone reactions. When the conversion reached 40% by mass, 140 parts by mass of methyl p-toluenesulfonate was added to stop the reaction. The reaction solution was cooled and filtered, and unreacted HDI was removed using a thin-film evaporator to obtain polyisocyanate P-3. The obtained polyisocyanate P-3 had a viscosity of 320 mPa·s at 25°C and an isocyanate group content of 22.0% by mass.

[0553] [Synthesis example 2-4]

[0554] (Synthesis of polyisocyanate P-4)

[0555] A nitrogen atmosphere was created in a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen inlet tube, and dropping funnel. 561.9 g of HDI and 38.1 g of isobutanol were added, and the urethane esterification reaction was carried out at 90°C for 60 minutes with stirring. The temperature was then raised to 120°C, and 0.28 g of a mineral oil solution with a solid content of 20% zirconium oxy2-ethylhexanoate was added as a urea esterification catalyst. After stirring for another 60 minutes, 0.097 g of an aqueous solution with a solid content of 85% phosphoric acid was added, and the reaction was stopped. The reaction solution was filtered, and unreacted HDI was removed using a thin-film evaporator to obtain polyisocyanate P-4. The obtained polyisocyanate P-4 was a pale yellow transparent liquid with a yield of 203 g, a viscosity of 130 mPa·s at 25°C, and an isocyanate group content of 18.8%. The results of 1H-NMR analysis showed that the molar ratio of isocyanurate groups to urea-formate groups was 3 / 97.

[0556] <Preparation of Polyisocyanate Compositions>

[0557] [Example 1]

[0558] (Preparation of the polyisocyanate composition PA-a1)

[0559] 1. Preparation of ionic polyisocyanate compounds

[0560] Add 5.9 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group / hydroxyl group = 25) to 92.1 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, and react under nitrogen reflux at 120°C for 3 hours with stirring. Then, remove the reflux, stir at 100°C for 1 hour, and continue the reaction to obtain an ionic polyisocyanate compound.

[0561] 2. Preparation of nonionic polyisocyanate compounds

[0562] 0.1 parts by mass of polyethylene glycol monomethyl ether (manufactured by Nippon Emulsifier Co., Ltd., trade name "MPG-130") with an average number of 9.4 repeating units of ethylene oxide (molar equivalent ratio of isocyanate group to hydroxyl group = 41) were added to 1.9 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and the reaction was carried out under nitrogen atmosphere and stirred at 90°C for 6 hours. After the reaction was completed, a nonionic polyisocyanate compound was obtained.

[0563] 3. Preparation of the polyisocyanate composition PA-a1

[0564] The total amount of ionic polyisocyanate compounds obtained in "1." and the total amount of nonionic polyisocyanate compounds obtained in "2." were stirred at 60°C for 2 hours under a nitrogen atmosphere. After reaching homogeneity, the polyisocyanate composition PA-a1 was obtained.

[0565] [Example 2]

[0566] (Preparation of the polyisocyanate composition PA-a2)

[0567] The polyisocyanate composition PA-a2 was prepared using 89.3 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.7 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 4.7 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.3 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0568] [Example 3]

[0569] (Preparation of the polyisocyanate composition PA-a3)

[0570] The polyisocyanate composition PA-a3 was prepared using 84.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.4 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.6 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0571] [Example 4]

[0572] (Preparation of the polyisocyanate composition PA-a4)

[0573] The polyisocyanate composition PA-a4 was prepared using 75.2 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 4.8 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 18.8 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 1.1 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 41), except that the same method as in Example 1 was used.

[0574] [Example 5]

[0575] (Preparation of the polyisocyanate composition PA-a5)

[0576] The polyisocyanate composition PA-a5 was prepared using 56.4 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 3.6 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 37.7 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 2.3 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 39), except that the same method as in Example 1 was used.

[0577] [Example 6]

[0578] (Preparation of the polyisocyanate composition PA-a6)

[0579] The polyisocyanate composition PA-a6 was prepared using 47.0 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 3.0 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 47.2 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 2.8 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 40), except that the same method as in Example 1 was used.

[0580] [Example 7]

[0581] (Preparation of the polyisocyanate composition PA-a7)

[0582] The polyisocyanate composition PA-a7 was prepared using 37.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 2.4 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 26), 56.6 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 3.4 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 40), except that the same method as in Example 1 was used.

[0583] [Example 8]

[0584] (Preparation of the polyisocyanate composition PA-a8)

[0585] The polyisocyanate composition PA-a8 was prepared using 89.3 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.7 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 4.5 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.5 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 21), except that the same method as in Example 1 was used.

[0586] [Example 9]

[0587] (Preparation of the polyisocyanate composition PA-a9)

[0588] Using 84.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.4 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.6 parts by mass of polyethylene glycol monomethyl ether (manufactured by Nippon Emulsifier Co., Ltd., trade name "MPG-081") with an average number of ethylene oxide repeating units of 15.0 (molar equivalent ratio of isocyanate group to hydroxyl group = 44), the polyisocyanate composition PA-a9 was prepared using the same method as in Example 1.

[0589] [Example 10]

[0590] (Preparation of the polyisocyanate composition PA-a10)

[0591] The polyisocyanate composition PA-a10 was prepared using 84.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.4 parts by mass of a mixture of HES / TBA and HES / DMCHA obtained in Synthesis Examples 1-4 (molar equivalent ratio of isocyanate group to hydroxyl group = 23), 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.6 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0592] [Example 11]

[0593] (Preparation of the polyisocyanate composition PA-a11)

[0594] Using 84.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1 and 5.4 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group / hydroxyl group = 25), except that an ionic polyisocyanate compound was prepared using the same method as in "1." of Example 1. Furthermore, using 9.4 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1 and 0.6 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group / hydroxyl group = 35), except that a nonionic polyisocyanate compound was prepared using the same method as in "2." of Example 1. The polyisocyanate composition PA-a11 was prepared using the same method as in "3." of Example 1.

[0595] [Example 12]

[0596] (Preparation of the polyisocyanate composition PA-a12)

[0597] The polyisocyanate composition PA-a12 was prepared using 89.3 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.7 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 4.7 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.3 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0598] [Example 13]

[0599] (Preparation of the polyisocyanate composition PA-a13)

[0600] The polyisocyanate composition PA-a13 was prepared using 84.7 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.3 parts by mass of HES / DMCHA obtained in Synthesis Examples 1-3 (molar equivalent ratio of isocyanate group to hydroxyl group = 21), 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.6 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0601] [Example 14]

[0602] (Preparation of the polyisocyanate composition PA-a14)

[0603] Add 3.5 parts by mass of 3-cyclohexylaminopropanesulfonic acid (hereinafter sometimes abbreviated as "CAPS") and 2.0 parts by mass of TBA to 84.5 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, and stir at 100°C for 5 hours under a nitrogen atmosphere with reflux, so that the molar ratio of isocyanate to amino group is 32, to produce a polyisocyanate compound containing an anionic compound. Next, using 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2 and 0.6 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the method is the same as in Example 1, to produce the polyisocyanate composition PA-a14.

[0604] [Example 15]

[0605] (Preparation of the polyisocyanate composition PA-a15)

[0606] The polyisocyanate composition PA-a15 was prepared using 84.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 5.4 parts by mass of HPS / TBA obtained in Synthesis Example 1-2 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 0.6 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0607] [Example 16]

[0608] (Preparation of the polyisocyanate composition PA-a16)

[0609] Polyisocyanate P-1 obtained in Synthesis Example 2-1: 94 parts by mass and HES / TBA obtained in Synthesis Example 1-1: 5.4 parts by mass (molar equivalent ratio of isocyanate group / hydroxyl group = 25) were added, and the reaction was carried out under nitrogen reflux at 120°C for 3 hours with stirring. Subsequently, MPG-130: 0.6 parts by mass (molar equivalent ratio of isocyanate group / hydroxyl group = 37) was added, and the reaction was carried out under nitrogen at 90°C for 6 hours with stirring to produce the polyisocyanate composition PA-a16.

[0610] [Example 17]

[0611] (Preparation of the polyisocyanate composition PA-a17)

[0612] The polyisocyanate composition PA-a17 was prepared using 47 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 3 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 47.2 parts by mass of polyisocyanate P-3 obtained in Synthesis Example 2-3, and 2.8 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0613] [Example 18]

[0614] (Preparation of the polyisocyanate composition PA-a18)

[0615] The polyisocyanate composition PA-a18 was prepared using 89.3 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-2, 5.7 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 25), 4.7 parts by mass of polyisocyanate P-4 obtained in Synthesis Example 2-4, and 0.3 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 37), except that the same method as in Example 1 was used.

[0616] [Example 19]

[0617] (Preparation of the polyisocyanate composition PA-a19)

[0618] 1. Preparation of ionic polyisocyanate compounds

[0619] Add 3.6 parts by mass of HES / TBA (molar equivalent ratio of isocyanate group / hydroxyl group = 33) obtained in Synthesis Example 1-1 to 56.4 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, and react under nitrogen reflux at 120°C for 3 hours with stirring. Then, remove the reflux, stir at 100°C for 1 hour, and continue the reaction to obtain an ionic polyisocyanate compound.

[0620] 2. Preparation of nonionic polyisocyanate compounds

[0621] 0.6 parts by mass of polyethylene glycol monomethyl ether (manufactured by Nippon Emulsifier Co., Ltd., trade name "MPG-130") with an average number of 9.4 repeating ethylene oxide units (molar equivalent ratio of isocyanate groups to hydroxyl groups = 39) were added to 9.4 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and the reaction was carried out under nitrogen atmosphere at 90°C for 6 hours. After the reaction was completed, a nonionic polyisocyanate compound was obtained.

[0622] 3. Preparation of the polyisocyanate composition PA-a19

[0623] The ionic polyisocyanate compound obtained in “1.”, the nonionic polyisocyanate compound obtained in “2.”, and the polyisocyanate P-1 obtained in Synthesis Example 2-1 (10.0 parts by mass) were stirred at 60°C for 2 hours under a nitrogen atmosphere. After reaching homogeneity, the polyisocyanate composition PA-a19 was obtained.

[0624] [Example 20]

[0625] (Preparation of the capped polyisocyanate composition PA-a20)

[0626] Add 30.6 g of 3,5-dimethylpyrazole to 69.4 g of polyisocyanate PA-a3 and 42.9 g of dipropylene glycol monomethyl ether obtained in Example 3, and stir at 80 °C for 2 hours to produce end-capped polyisocyanate PA-a20.

[0627] [Example 21]

[0628] (Preparation of the capped polyisocyanate composition PA-a21)

[0629] Add 30.6 g of 3,5-dimethylpyrazole to 69.4 g of polyisocyanate PA-a16 obtained in Example 16 and 42.9 g of dipropylene glycol monomethyl ether, and stir at 80 °C for 2 hours to produce end-capped polyisocyanate PA-a21.

[0630] [Comparative Example 1]

[0631] (Preparation of the polyisocyanate composition PA-b1)

[0632] Add 5.4 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group / hydroxyl group = 33) to 84.6 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, and react under nitrogen reflux at 120°C for 3 hours with stirring. Then, remove the reflux, stir at 100°C for 1 hour, and continue the reaction to obtain an ionic polyisocyanate compound.

[0633] Then, 10.0 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2 were added to the obtained ionic polyisocyanate compound, and stirred at 60°C for 2 hours under a nitrogen atmosphere. After reaching homogeneity, the polyisocyanate composition PA-b1 was obtained.

[0634] [Comparative Example 2]

[0635] (Preparation of the polyisocyanate composition PA-b2)

[0636] 5.1 parts by mass of polyethylene glycol monomethyl ether (manufactured by Nippon Emulsifier Co., Ltd., trade name "MPG-130") with an average repeating number of 9.4 ethylene oxide units (molar equivalent ratio of isocyanate groups to hydroxyl groups = 40) were added to 84.9 parts by mass of polyisocyanate P-2 obtained in Synthetic Example 2-2, and the reaction was carried out under nitrogen atmosphere at 90°C for 6 hours. After the reaction was completed, a nonionic polyisocyanate compound was obtained.

[0637] Then, 10.0 parts by mass of polyisocyanate P-1 obtained in synthesis example 2-1 were added, and the mixture was stirred at 60°C for 2 hours under a nitrogen atmosphere. After homogenization, the polyisocyanate composition PA-b2 was obtained.

[0638] [Comparative Example 3]

[0639] (Preparation of the polyisocyanate composition PA-b3)

[0640] 1. Preparation of ionic polyisocyanate compounds

[0641] 1.8 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group / hydroxyl group = 33) were added to 28.2 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1. The reaction was carried out under nitrogen reflux and stirred at 120°C for 3 hours. Subsequently, the reflux was removed, and the reaction was continued by stirring at 100°C for 1 hour to obtain an ionic polyisocyanate compound.

[0642] 2. Preparation of nonionic polyisocyanate compounds

[0643] 4.0 parts by mass of polyethylene glycol monomethyl ether (manufactured by Nippon Emulsifier Co., Ltd., trade name "MPG-130") with an average number of 9.4 repeating ethylene oxide units (molar equivalent ratio of isocyanate groups to hydroxyl groups = 39) were added to 66.0 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and the reaction was carried out under nitrogen atmosphere at 90°C for 6 hours. After the reaction was completed, a nonionic polyisocyanate compound was obtained.

[0644] 3. Preparation of the polyisocyanate composition PA-b3

[0645] The ionic polyisocyanate compound obtained in "1." and the nonionic polyisocyanate compound obtained in "2." were stirred at 60°C for 2 hours under a nitrogen atmosphere. After homogenization, the polyisocyanate composition PA-b3 was obtained.

[0646] [Comparative Example 4]

[0647] (Preparation of the polyisocyanate composition PA-b4)

[0648] The polyisocyanate composition PA-b4 was prepared using 14.1 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 0.9 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 33), 80.2 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 4.8 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 40), except that the same method as in Comparative Example 3 was used.

[0649] [Comparative Example 5]

[0650] (Preparation of the polyisocyanate composition PA-b5)

[0651] The polyisocyanate composition PA-b5 was prepared using 4.7 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 0.3 parts by mass of HES / TBA obtained in Synthesis Example 1-1 (molar equivalent ratio of isocyanate group to hydroxyl group = 33), 89.6 parts by mass of polyisocyanate P-2 obtained in Synthesis Example 2-2, and 5.4 parts by mass of MPG-130 (molar equivalent ratio of isocyanate group to hydroxyl group = 39), except that the same method as in Comparative Example 3 was used.

[0652] The physical properties of each polyisocyanate composition were determined and evaluated using the methods described above. The results are shown in the table below.

[0653] [Table 1]

[0654]

[0655] [Table 2]

[0656]

[0657] [Table 3]

[0658]

[0659] [Table 4]

[0660]

[0661] [Table 5]

[0662]

[0663] [Table 6]

[0664]

[0665] [Table 7]

[0666]

[0667] As shown in the table above, the polyisocyanate compositions PA-a1 to PA-a19 (Examples 1 to 19) containing ionic polyisocyanate compound (A) and nonionic polyisocyanate compound (B) with a mass ratio (a2) / (b2) within a specific range, and the end-capped polyisocyanate compositions PA-a20 to PA-a21 (Examples 20 to 21) exhibit good water dispersibility, shelf life when prepared as coating compositions, and appearance, water resistance, and hardness when prepared as coating films.

[0668] Furthermore, in the comparison of polyisocyanate compositions PA-a1 to PA-a7 (Examples 1 to 7) with different mass ratios (A) / (B) and (a2) / (b2), it was observed that the lower the mass ratio (A) / (B) and (a2) / (b2), the better the shelf life. On the other hand, it was observed that the higher the mass ratio (A) / (B) and (a2) / (b2), the better the hardness of the coating film.

[0669] Furthermore, in a comparison of polyisocyanate compositions PA-a2 and PA-a8 (Examples 2 and 8) with the same mass ratio (A) / (B) but different mass ratios (a2) / (b2), a tendency was observed that the lower the mass ratio (a2) / (b2), the better the shelf life.

[0670] In a comparison of polyisocyanate compositions PA-a3 and PA-a11 (Examples 3 and 11) of different types of polyisocyanate compounds that serve as raw materials for nonionic polyisocyanate compounds, regardless of the type of polyisocyanate compound, the water dispersibility, shelf life when made into a coating composition, and appearance, water resistance and hardness when made into a coating film were all good.

[0671] In a comparison of polyisocyanate compositions PA-a8 and PA-a12 (Examples 8 and 12) with different contents of structural units derived from ionic compounds and structural units derived from nonionic compounds, a tendency was observed that the greater the contents of structural units derived from ionic compounds and structural units derived from nonionic compounds, the better the shelf life.

[0672] In a comparison of polyisocyanate compositions PA-a6 and PA-a17 (Examples 6 and 17) of different types of polyisocyanate compounds that serve as raw materials for nonionic polyisocyanate compounds, it was observed that the more the total content of diketone groups and urethane groups and the molar ratio of diketone groups to urethane groups decreased and the viscosity of the composition increased, the better the water resistance of the coating film at 40°C.

[0673] In a comparison of polyisocyanate compositions PA-a2 and PA-a19 (Examples 2 and 19) of different types of polyisocyanate compounds that serve as raw materials for ionic and nonionic polyisocyanate compounds, it was observed that the more the total content of diketone and urethane groups decreased and the more the molar ratio of diketone to urethane groups increased, the better the water resistance and hardness of the coating film at 40°C.

[0674] On the other hand, the polyisocyanate composition PA-b1 (Comparative Example 1) containing ionic polyisocyanate compound (A) and not containing nonionic polyisocyanate compound (B), the polyisocyanate composition PA-b1 (Comparative Example 2) containing nonionic polyisocyanate compound (B) and not containing ionic polyisocyanate compound (A), and the polyisocyanate compositions PA-b3 to PA-b5 (Comparative Examples 3 to 6) containing ionic polyisocyanate compound (A) and nonionic polyisocyanate compound (B) but with a mass ratio (a2) / (b2) less than 50 / 50, did not achieve good results in terms of water dispersibility, shelf life when made into a coating composition, and appearance, water resistance and hardness when made into a coating film.

[0675] Industrial availability

[0676] The polyisocyanate composition according to this embodiment provides a polyisocyanate composition that exhibits excellent shelf life and dispersibility when dispersed in water or a water-containing main agent, and also provides excellent appearance, water resistance, and hardness when formed into a coating film. The coating composition of this embodiment, comprising the aforementioned polyisocyanate composition, provides excellent appearance, water resistance, and hardness when formed into a coating film. The coating substrate of this embodiment provides a coating film formed by curing the aforementioned coating composition, exhibiting excellent appearance, water resistance, and hardness.

Claims

1. A polyisocyanate composition comprising an ionic polyisocyanate compound (A) and a nonionic polyisocyanate compound (B), The ionic polyisocyanate compound (A) is obtained by reacting a polyisocyanate compound (a1) with one or more ionic compounds selected from the group consisting of anionic and cationic compounds. The nonionic polyisocyanate compound (B) is obtained by reacting a nonionic compound with a polyisocyanate compound (b1). The polyisocyanate compound (a1) and the polyisocyanate compound (b1) are respectively polyisocyanate compounds obtained by reacting one or more diisocyanates selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates. The mass ratio (a2) / (b2) of the structural unit (a2) derived from the ionic compound contained in the ionic polyisocyanate compound (A) relative to the structural unit (b2) derived from the nonionic compound contained in the nonionic polyisocyanate compound (B) is 50 / 50 or more and 98 / 2 or less. The mass ratio (A) / (B) of the ionic polyisocyanate compound (A) to the nonionic polyisocyanate compound (B) is 40 / 60 or more and 99 / 1 or less. The polyisocyanate composition contains isocyanurate group, iminooxadiazine dione group, ureidone group and ureocarbamate group. Relative to the total molar amount of the isocyanurate group, iminooxadiazine dione group, ureidone group, and ureocarbamate group, the total content of the ureidone group and the ureocarbamate group is 1.0 mol% or more and 30.0 mol% or less. The molar ratio of the diketone group to the urethane group is 0.1 or more and 20.0 or less. The nonionic compound is a polyalkylene glycol alkyl ether having the structure shown in general formula (I). In general formula (I), R 11 R is an alkylene group having 1 or more but less than 4 carbon atoms. 12 It is an alkyl group with 1 or more but less than 4 carbon atoms, and n11 is 4.0 or more but less than 20.

2. The polyisocyanate composition according to claim 1, wherein, The mass ratio (a2) / (b2) of the structural unit (a2) derived from the ionic compound contained in the ionic polyisocyanate compound (A) relative to the structural unit (b2) derived from the nonionic compound contained in the nonionic polyisocyanate compound (B) is 70 / 30 or more and 95 / 5 or less.

3. The polyisocyanate composition according to claim 1, wherein, The mass ratio (a2) / (b2) of the structural unit (a2) derived from the ionic compound contained in the ionic polyisocyanate compound (A) relative to the structural unit (b2) derived from the nonionic compound contained in the nonionic polyisocyanate compound (B) is 80 / 20 or more and 90 / 10 or less.

4. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The mass ratio (A) / (B) of the ionic polyisocyanate compound (A) to the nonionic polyisocyanate compound (B) is 50 / 50 or more and 99 / 1 or less.

5. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The mass ratio (A) / (B) of the ionic polyisocyanate compound (A) to the nonionic polyisocyanate compound (B) is 80 / 20 or more and 90 / 10 or less.

6. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The total content of the urea diketone group and the urea formate group relative to the total molar amount of the isocyanurate group, iminooxadiazine diketone group, urea diketone group and urea formate group is 2.0 mol% or more and 25.0 mol% or less, and the molar ratio of the urea diketone group to the urea formate group is 0.2 or more and 10.0 or less.

7. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The mass fraction of the ionic compound bonded to the ionic polyisocyanate compound (A) relative to the total mass of the polyisocyanate composition is 1% by mass or more and 40.0% by mass or less.

8. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The mass fraction of the nonionic compound bonded to the nonionic polyisocyanate compound (B) relative to the total mass of the polyisocyanate composition is 0.1% by mass or more and 10.0% by mass or less.

9. The polyisocyanate composition according to claim 1, wherein, The mixing ratio of the polyisocyanate compound (b1) to the polyalkylene glycol alkyl ether is in the range of 2 or more and 400 or less, based on the molar ratio of isocyanate group to hydroxyl group.

10. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The anionic compound is one or more compounds selected from the group consisting of compounds containing carboxylic acid groups, compounds containing phosphate groups, and compounds containing sulfonic acid groups.

11. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The anionic compound includes a compound containing a sulfonic acid group, wherein the compound containing the sulfonic acid group is one or more sulfonic acids selected from the group consisting of sulfonic acids containing hydroxyl groups and sulfonic acids containing amino groups.

12. The polyisocyanate composition according to claim 11, wherein, The sulfonic acid containing a hydroxyl group is a compound represented by the following general formula (II). HO—R 21 —SO3H (II) In general formula (II), R 21 R is a hydrocarbon group consisting of at least one of the groups selected from hydroxyl, ether, ester, carbonyl, and imino, having 1 or more and 10 carbon atoms. 21 The ring structure may optionally include an aromatic ring, a five-membered or six-membered ring containing two nitrogen atoms, or a five-membered or six-membered ring containing nitrogen and oxygen atoms.

13. The polyisocyanate composition according to claim 12, wherein, The mixing ratio of the hydroxyl-containing sulfonic acid to the polyisocyanate compound (a1) is in the range of 2 or more and 400 or less, based on the molar ratio of isocyanate group to hydroxyl group.

14. The polyisocyanate composition according to claim 11, wherein, The amino-containing sulfonic acid is a compound represented by the following general formula (III). In general formula (III), R 31 and R 32 R consists of hydrogen atoms or, optionally, hydrocarbon groups containing 1 or more but less than 12 carbon atoms, each being an independent hydrogen atom. 32 and R 31 At least one of them is a hydrogen atom, R 33 It can be any hydrocarbon group containing 1 or more but less than 12 carbon atoms.

15. The polyisocyanate composition according to any one of claims 1 to 3, wherein, At least a portion of the isocyanate groups of the ionic polyisocyanate compound (A) and / or the nonionic polyisocyanate compound (B) are capped by a thermally dissociative capping agent.

16. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The viscosities of the polyisocyanate compounds (a1) and (b1) at 25°C are above 300 mPa·s and below 5,000 mPa·s, respectively.

17. The polyisocyanate composition according to any one of claims 1 to 3, wherein, The isocyanate groups in the polyisocyanate compounds (a1) and (b1) are respectively 18% by mass and 25% by mass.

18. A coating composition comprising the polyisocyanate composition of any one of claims 1 to 17, and a resin.

19. A coating substrate coated with the coating composition of claim 18.

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