Block polyisocyanate composition, curable resin composition containing the composition, and cured product

Abstract

The present invention provides a block polyisocyanate composition with excellent storage stability, a curable resin composition containing the composition, and a cured product. [Solution] A blocked polyisocyanate composition comprising a blocked polyisocyanate compound in which the isocyanate group of a polyisocyanate compound is blocked by a secondary amine compound represented by the following formula (1), and an amine compound represented by at least one formula selected from the group consisting of the following formulas (2-1), (2-2), (2-3), and (2-4). JPEG2026062554000020.jpg37169

Description

[Technical Field]

[0001] The present invention relates to a block polyisocyanate composition, a curable resin composition containing the composition, and a cured product. [Background technology]

[0002] Blocked polyisocyanate compounds are compounds obtained by reacting a polyisocyanate compound with a blocking agent having active hydrogen groups that can react with isocyanate groups. Blocked polyisocyanate compounds are inactivated at room temperature because the isocyanate groups of the polyisocyanate are encapsulated by the blocking agent, but the blocking agent dissociates upon heating, and the isocyanate groups are regenerated. Due to these properties, blocked polyisocyanate compounds are mixed with polyols and curing catalysts to form one-component paint compositions, which are widely used in applications such as paints.

[0003] For example, Patent Document 1 describes a blocked isocyanate composition comprising a blocked isocyanate compound obtained from a triisocyanate compound represented by formula (I) as described in claim 1 of the international publication and at least two types of blocking agents, and a one-component coating composition comprising the blocked isocyanate composition and a polyol. Furthermore, it is stated that the formulation may include two types of blocking agents, an amine compound and a pyrazole compound, and that it may also contain metal salts such as dibutyltin dilaurate or tertiary amines as a catalyst for accelerating curing. Furthermore, the invention described in Patent Document 1 provides a blocked isocyanate composition that has low viscosity and excellent low crystallinity, low-temperature curing properties, and storage stability of the paint.

[0004] Furthermore, for example, Patent Document 2 describes a blocked isocyanate composition comprising a blocked isocyanate derived from a triisocyanate compound represented by formula (I) as described in claim 1 of the published patent, and a blocking agent comprising an amine compound, and a paint composition comprising the blocked isocyanate composition and an active hydrogen compound. Furthermore, it is stated that the amine compound may be a secondary amine compound and may contain a curing-accelerating catalyst such as an amine compound. Furthermore, the invention described in Patent Document 2 provides a block isocyanate composition that maintains good blocking resistance, has excellent curability, and exhibits excellent gloss and image quality when applied as a coating film. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2018 / 235896 [Patent Document 2] Japanese Patent Publication No. 2022-041366 [Overview of the project] [Problems that the invention aims to solve]

[0006] In the conventional technology described above, even when a blocked polyisocyanate composition containing a blocked isocyanate compound, a polyol, and a curing catalyst is stored at room temperature, the blocked polyisocyanate composition may harden during storage. For this reason, there is a need for a blocked polyisocyanate composition that prevents hardening during storage and exhibits excellent storage stability. Therefore, the problem to be solved by the present invention is to improve the storage stability of a blocked polyisocyanate composition and a curable resin composition containing the composition, to provide a blocked polyisocyanate composition having excellent storage stability and a curable resin composition containing the composition, and to provide a cured product obtained by curing the curable resin composition.

Means for Solving the Problem

[0007] As a result of intensive studies, the inventors of the present application have found that the present invention can solve the above problems and have completed the present invention. That is, the present invention provides the blocked polyisocyanate compositions of the following [1] to [3], the curable resin compositions of [4] to [6], and the cured products of [7]. [1] A blocked polyisocyanate composition containing a blocked polyisocyanate compound in which an isocyanate group of a polyisocyanate compound is blocked by a secondary amine compound represented by the following formula (1) and an amine compound represented by at least one formula selected from the group consisting of the following formula (2-1), formula (2-2), formula (2-3) and formula (2-4). Formula (1): [Chemical Formula] (In the formula, R 1 , R 2 , R 3 , R 4 and R 5 are each independent. R 1 , R 2 and R 3 represent a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hetero atom. R 4 and R 5 represent a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hetero atom or a hydrogen atom. R 1 , R 2 , R 3 , R 4 and R 5 may together with the carbon atom to which they are attached form a ring structure.) Formula (2-1): [ka] (R 6 and R 7 These are independent of each other. 6 and R 7 R represents a hydrocarbon group having 1 to 20 carbon atoms, which may be substituted with heteroatoms. 6 and R 7 They may also form a ring structure together with the nitrogen atom to which they are bonded. Formula (2-2): [ka] (R 8 , R 9 , R 10 , R 11 and R 12 These are independent of each other. 8 , R 9 , R 10 , R 11 and R 12 R represents a hydrogen atom or a hydrocarbon group. 8 , R 9 , R 10 , R 11 and R 12 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and these heteroatoms may form a ring structure together with the carbon atoms to which they are bonded. Formula (2-3): [ka] (R 13 , R 14 , R 15 and R 16 These are independent of each other. 13 , R 14 , R 15 and R 16 R represents a hydrogen atom or a hydrocarbon group. 13 , R 14 , R 15 and R 16If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and these heteroatoms may form a ring structure together with the carbon atoms to which they are bonded. Formula (2-4): [ka] (R 17 , R 18 , R 19 and R 20 These are independent of each other. 17 , R 18 , R 19 and R 20 R represents a hydrogen atom or a hydrocarbon group. 17 , R 18 , R 19 and R 20 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and may form a ring structure together with the carbon and / or nitrogen atoms to which they are bonded. [2] The block polyisocyanate composition according to [1], wherein the polyisocyanate compound is at least one polyisocyanate selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates and aromatic aliphatic polyisocyanates, or a modified polyisocyanate formed from at least one selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates and aromatic aliphatic polyisocyanates. [3] R of the secondary amine compound represented by formula (1) 1 , R 2 and R 3 R is a hydrocarbon group having 1 to 2 carbon atoms. 4 and R 5 The block polyisocyanate composition according to [1], wherein is a hydrocarbon group having 1 to 2 carbon atoms or a hydrogen atom. [4] A curable resin composition comprising a block polyisocyanate composition according to any one of items [1] to [3], and a compound having an isocyanate-reactive group. [5] The curable resin composition according to [4], wherein the compound having an isocyanate reactive group is a polyol compound or a polyamine compound. [6] A curable resin composition comprising the curable resin composition described in [4] and a curing catalyst. [7] A cured product obtained by curing the curable resin composition described in [6]. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a block polyisocyanate composition with excellent storage stability, a curable resin composition containing the composition, and a cured product. [Modes for carrying out the invention]

[0009] <Blocked polyisocyanate composition> The blocked polyisocyanate composition of the present invention contains a blocked polyisocyanate compound in which the isocyanate group of a polyisocyanate compound is blocked by a secondary amine compound represented by formula (1), and an amine compound represented by at least one formula selected from the group consisting of formulas (2-1), (2-2), (2-3), and (2-4).

[0010] <Blocked polyisocyanate compounds> Blocked polyisocyanate compounds will be described. Examples of blocked polyisocyanate compounds include compounds obtained by reacting a polyisocyanate compound with a blocking agent, thereby encapsulating the isocyanate groups in the polyisocyanate compound with the blocking agent. Blocked polyisocyanate compounds may be single compounds or mixtures of two or more types.

[0011] <Polyisocyanate compounds> The polyisocyanate compound that constitutes the blocked polyisocyanate compound is not particularly limited as long as it is a compound having two or more isocyanate groups, but examples of polyisocyanate compounds include the following: (i) Aliphatic polyisocyanates, (ii) Alicyclic polyisocyanates, (iii) Aromatic polyisocyanates, (iv) Aromatic aliphatic polyisocyanates, (v) A modified polyisocyanate formed from at least one selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and aromatic aliphatic polyisocyanates.

[0012] (i) Examples of aliphatic polyisocyanates include 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, and dimer acid diisocyanate.

[0013] (ii) Examples of alicyclic polyisocyanates include 1,3-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, 3-isocyanatomethyl-3,3,5-trimethylcyclohexane (isophorone diisocyanate (IPDI)), bis-(4-isocyanatocyclohexyl)methane, norbornane diisocyanate, etc.

[0014] (iii) Examples of aromatic polyisocyanates include 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, 1,4-phenylenediisocyanate, 2,4-tolylenediisocyanate, 2,6-tolylenediisocyanate, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5-naphthylenediisocyanate, and the like.

[0015] (iv) Examples of aromatic aliphatic polyisocyanates include 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, and α,α,α',α'-tetramethylxylylene diisocyanate.

[0016] (v) Examples of modified polyisocyanates include isocyanate-terminated compounds and / or reaction products of the polyisocyanate compound and / or the isocyanate-terminated compound obtained by the reaction of the polyisocyanate compound with a compound having an active hydrogen group (for example, adduct-type polyisocyanates, isocyanate modified products obtained by allophanate reaction, carbodiimide reaction, uretdione reaction, isocyanurate reaction, uretonimine reaction, biuret reaction, etc.), and adduct-type polyisocyanates, polyisocyanates modified by isocyanurate reaction (polyisocyanates having isocyanurate bonds), polyisocyanates modified by biuret reaction (polyisocyanates having biuret bonds), and polyisocyanates having urethane bonds are preferred.

[0017] [Polyisocyanates containing biuret bonds] Polyisocyanates containing biuret bonds are obtained by reacting a polyisocyanate with a so-called biuretizing agent such as water, tert-butanol, or urea, in a molar ratio of isocyanate groups between the biuretizing agent and the polyisocyanate of approximately 1 / 2 to 1 / 100, and then removing the unreacted polyisocyanate for purification.

[0018] Examples of polyisocyanates having biuret bonds include biuret-modified 1,6-hexamethylene diisocyanate (HDI), biuret-modified isophorone diisocyanate (IPDI), and biuret-modified toluene diisocyanate (TDI), as shown in formula (1a) below. Commercially available products include Desmodule N75, Desmodule N100, and Desmodule N3200 from Sumika Covestro Urethane Co., Ltd., and Duranate 24A-100, Duranate 22A-75P, and Duranate 21S-75E from Asahi Kasei Corporation.

[0019] Formula (1a): [ka]

[0020] [Polyisocyanates containing isocyanurate bonds] Polyisocyanates containing isocyanurate bonds can be obtained, for example, by carrying out a cyclic trimerization reaction using a catalyst, stopping the reaction when the conversion rate reaches approximately 5 to 80% by mass, and then removing and purifying the unreacted polyisocyanate. In this process, 1-6 valent alcohol compounds can be used in combination.

[0021] Generally, a catalyst that is basic is preferred for the above isocyanurate reaction. Examples of the above catalyst include: (1) Hydroxides of tetraalkylammonium such as tetramethylammonium, tetraethylammonium, and trimethylbenzylammonium, and organic weak salts such as acetic acid and capric acid, (2) Hydroxyalkylammonium hydroxides such as trimethylhydroxypropylammonium, trimethylhydroxyethylammonium, triethylhydroxypropylammonium, and triethylhydroxyethylammonium, and organic weak salts such as acetic acid and capric acid, (3) Metal salts of alkylcarboxylic acids, such as tin, zinc, lead, (4) Metal alkoxides such as sodium and potassium, (5) Aminosilyl group-containing compounds such as hexamethyldisilazane, (6) Mannich bases, (7) Combined use of tertiary amines and epoxy compounds, (8) Phosphorus compounds such as tributylphosphine, Examples include the following, and two or more types may be used in combination.

[0022] If the catalyst may adversely affect the properties of the paint or coating film, the catalyst may be neutralized with an acidic compound. Examples of the acidic compound include inorganic acids such as hydrochloric acid, phosphorous acid, and phosphoric acid; sulfonic acids or their derivatives such as methanesulfonic acid, p-toluenesulfonic acid, p-toluenesulfonate methyl ester, and p-toluenesulfonate ethyl ester; ethyl phosphate, diethyl phosphate, isopropyl phosphate, diisopropyl phosphate, butyl phosphate, dibutyl phosphate, 2-ethylhexyl phosphate, di(2-ethylhexyl) phosphate, isodecyl phosphate, diisodecyl phosphate, oleyl acid phosphate, tetracosyl acid phosphate, ethyl glycol acid phosphate, butyl pyrophosphate, and butyl phosphate, and two or more may be used in combination.

[0023] Examples of polyisocyanates having isocyanurate bonds include isocyanurate modified forms of HDI, IPDI, and TDI shown in formula (1b) below. Commercially available products include Sumijoul N3300, Desmodule 3900, Desmodule Z4470BA, Desmodule XP2763, Desmodule IL1351BA, and Desmodule HLBA from Sumika Covestro Urethane Co., Ltd., and Duranate TPA-100, Duranate MFA-75B, Duranate TUL-100, and Duranate TSA-100 from Asahi Kasei Corporation.

[0024] Formula (1b): [ka]

[0025] [Polyisocyanates containing urethane bonds] Polyisocyanates containing urethane bonds can be obtained, for example, by reacting a diisocyanate with a divalent to hexavalent alcohol compound such as trimethylolpropane (hereinafter referred to as TMP) in a molar ratio of hydroxyl groups of the alcohol compound to isocyanate groups of the polyisocyanate of approximately 1 / 2 to approximately 1 / 100, and then removing and purifying the unreacted polyisocyanate. Removal and purification of unreacted polyisocyanate is not always necessary.

[0026] Polyisocyanates having urethane bonds include, for example, reaction products of HDI and TMP, reaction products of IPDI and TMP, and reaction products of TDI and TMP. Commercially available products include Sumijoule N3300, Desmodule 3900, Desmodule Z4470BA, Desmodule XP2763, Desmodule IL1351BA, and Desmodule HLBA from Sumika Covestro Urethane Co., Ltd., and Duranate TPA-100, Duranate MFA-75B, Duranate TUL-100, and Duranate TSA-100 from Asahi Kasei Corporation.

[0027] In one embodiment, the polyisocyanate compound may be a polyisocyanate represented by the following formula (3), or a modified polyisocyanate represented by the following formula (3).

[0028] Formula (3): [ka] (In the formula, A represents a residue obtained by removing the isocyanate group from at least one polyisocyanate selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and aromatic aliphatic polyisocyanates, or a residue obtained by removing the isocyanate group from a modified polyisocyanate formed from at least one polyisocyanate selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and aromatic aliphatic polyisocyanates. x is an integer between 2 and 20.)

[0029] The polyisocyanate represented by formula (3) is preferably (i) an aliphatic polyisocyanate or (ii) an alicyclic polyisocyanate. The modified polyisocyanate represented by formula (3) is preferably a modified polyisocyanate formed from at least one selected from the group consisting of (v) aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and aromatic aliphatic polyisocyanates. These polyisocyanates may be used individually or as a mixture of two or more types.

[0030] <Blocking agent> In the present invention, the blocking agent that encapsulates a portion of the isocyanate groups of the above-mentioned polyisocyanate or modified polyisocyanate is a secondary amine compound represented by the following formula (1).

[0031] Formula (1): [ka] (In the formula, R 1 , R 2 , R 3 , R 4 and R 5 These are independent of each other. 1 , R 2 and R 3 R represents a hydrocarbon group having 1 to 20 carbon atoms, which may be substituted with heteroatoms. 4 and R 5 R represents a hydrocarbon group having 1 to 20 carbon atoms, or a hydrogen atom, which may be substituted with a heteroatom. 1 , R 2 , R 3 , R 4 and R 5 They may also form a ring structure together with the carbon atoms to which they are bonded.

[0032] In formula (1), R 1 , R 2 , R 3 , R 4 and R5 are each independent.

[0033] In formula (1), R 1 , R 2 , and R 3 are hydrocarbon groups having 1 to 20 carbon atoms which may be substituted with heteroatoms, preferably hydrocarbon groups having 1 to 12 carbon atoms which may be substituted with heteroatoms, more preferably hydrocarbon groups having 1 to 6 carbon atoms which may be substituted with heteroatoms, still more preferably hydrocarbon groups having 1 to 4 carbon atoms which may be substituted with heteroatoms, particularly preferably hydrocarbon groups having 1 to 2 carbon atoms which may be substituted with heteroatoms, and most preferably hydrocarbon groups having 1 to 2 carbon atoms.

[0034] In formula (1), R 4 and R 5 are hydrocarbon groups having 1 to 20 carbon atoms which may be substituted with heteroatoms or hydrogen atoms. When R 4 and R 5 are hydrocarbon groups having 1 to 20 carbon atoms which may be substituted with heteroatoms, preferably hydrocarbon groups having 1 to 12 carbon atoms which may be substituted with heteroatoms, more preferably hydrocarbon groups having 1 to 6 carbon atoms which may be substituted with heteroatoms, and still more preferably hydrocarbon groups having 1 to 4 carbon atoms which may be substituted with heteroatoms. R 4 and R 5 are particularly preferably hydrocarbon groups having 1 to 2 carbon atoms which may be substituted with heteroatoms or hydrogen atoms, and most preferably hydrocarbon groups having 1 to 2 carbon atoms or hydrogen atoms.

[0035] R 1 , R 2 , R 3 , R 4 , and R 5However, examples of hydrocarbon groups that are not substituted with heteroatoms include methyl group, ethyl group, propyl group, n-butyl group, s-butyl group, t-butyl group, pentyl group, neopentyl group, hexyl group, octyl group, benzyl group, and phenyl group, with methyl group, ethyl group, neopentyl group, and phenyl group being preferred, and methyl group and ethyl group being more preferred.

[0036] Also, R 1 , R 2 , R 3 , R 4 and R 5 However, a hydrocarbon group that is substituted with a heteroatom is a hydrocarbon group in which at least one of the -CH2- atoms constituting the hydrocarbon group is substituted with at least one of the following: -O-, -NH-, -N(R)- (where R represents a hydrocarbon group), -S-, -SO2-, etc.

[0037] Also, R 1 , R 2 , R 3 , R 4 and R 5 These may also form a ring structure together with the carbon atoms to which they are bonded.

[0038] Examples of secondary amine compounds represented by formula (1) include tert-butyl-ethylamine, tert-butyl-n-propylamine, tert-butyl-iso-propylamine, tert-butyl-n-butylamine, tert-butyl-sec-butylamine, tert-butyl-n-octylamine, tert-butyl-2-ethylhexylamine, tert-pentyl-ethylamine, tert-pentyl-n-propylamine, tert-pentyl-iso-propylamine, ter Examples include t-pentyl-sec-butylamine, 1,1,3,3-tetramethylbutyl-ethylamine, 1,1,3,3-tetramethylbutyl-n-propylamine, 1,1,3,3-tetramethylbutyl-iso-propylamine, 1,1,3,3-tetramethylbutyl-n-butylamine, 1,1,3,3-tetramethylbutyl-sec-butylamine, 1,1,3,3-tetramethylbutyl-n-octylamine, and 1,1,3,3-tetramethylbutyl-2-ethylhexylamine.

[0039] <Amine compounds> The amine compound contained in the block polyisocyanate composition of the present invention is an amine compound represented by at least one formula selected from the group consisting of formulas (2-1), (2-2), (2-3), and (2-4).

[0040] [Amine compounds represented by formula (2-1)] Formula (2-1): [ka] (R 6 and R 7 These are independent of each other. 6 and R 7 R represents a hydrocarbon group having 1 to 20 carbon atoms, which may be substituted with heteroatoms. 6 and R 7 They may also form a ring structure together with the nitrogen atom to which they are bonded.

[0041] In formula (2-1), R 6 and R 7They are independent of each other.

[0042] In formula (2-1), R 6 and R 7 is a hydrocarbon group having 1 to 20 carbon atoms, which may be substituted with a heteroatom; preferably a hydrocarbon group having 1 to 12 carbon atoms, which may be substituted with a heteroatom; more preferably a hydrocarbon group having 1 to 8 carbon atoms, which may be substituted with a heteroatom; even more preferably a hydrocarbon group having 1 to 6 carbon atoms, which may be substituted with a heteroatom; and even more preferably a hydrocarbon group having 1 to 4 carbon atoms, which may be substituted with a heteroatom.

[0043] R 6 and R 7 However, examples of hydrocarbon groups that are not substituted with heteroatoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, s-butyl group, t-butyl group, pentyl group, neopentyl group, hexyl group, octyl group, benzyl group, and phenyl group. Preferably, the group is methyl, ethyl, neopentyl, or phenyl; more preferably, the group is methyl, ethyl, isopropyl, or t-butyl; and even more preferably, the group is ethyl, isopropyl, or t-butyl.

[0044] Also, R 6 and R 7 However, a hydrocarbon group that is substituted with a heteroatom is a hydrocarbon group in which at least one of the -CH2- atoms constituting the hydrocarbon group is substituted with at least one of the following: -O-, -NH-, -N(R)- (where R represents a hydrocarbon group), -S-, -SO2-, etc.

[0045] Also, R 6 and R 7 These may also form a ring structure together with the nitrogen atom to which they are bonded.

[0046] Examples of amine compounds represented by formula (2-1) include t-butylmethylamine, t-butylethylamine, t-butylpropylamine, t-butylisopropylamine, t-butylbutylamine, t-butyl-s-butylamine, di(t-butyl)amine, t-butylphenylamine, and t-butylbenzylamine.

[0047] [Amine compounds represented by formula (2-2)] Formula (2-2): [ka] (R 8 , R 9 , R 10 , R 11 and R 12 These are independent of each other. 8 , R 9 , R 10 , R 11 and R 12 R represents a hydrogen atom or a hydrocarbon group. 8 , R 9 , R 10 , R 11 and R 12 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and these heteroatoms may form a ring structure together with the carbon atoms to which they are bonded.

[0048] In formula (2-2), R 8 , R 9 , R 10 , R 11 and R 12 They are independent of each other.

[0049] R 8 , R 9 , R 10 , R 11 and R 12 is a hydrogen atom or a hydrocarbon group.

[0050] R 8 , R 9 , R 10 , R 11 and R12 If the group is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, preferably a hydrocarbon group having 1 to 12 carbon atoms that may be substituted with heteroatoms, more preferably a hydrocarbon group having 1 to 6 carbon atoms that may be substituted with heteroatoms, even more preferably a hydrocarbon group having 1 to 4 carbon atoms that may be substituted with heteroatoms, and even more preferably a hydrocarbon group having 1 to 2 carbon atoms that may be substituted with heteroatoms.

[0051] R 8 , R 9 , R 10 , R 11 and R 12 However, examples of hydrocarbon groups that are not substituted with heteroatoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, s-butyl group, t-butyl group, pentyl group, neopentyl group, hexyl group, octyl group, benzyl group, and phenyl group, with methyl group, ethyl group, neopentyl group, and phenyl group being preferred, and methyl group and ethyl group being more preferred.

[0052] Also, R 8 , R 9 , R 10 , R 11 and R 12 However, a hydrocarbon group that is substituted with a heteroatom is a hydrocarbon group in which at least one of the -CH2- atoms constituting the hydrocarbon group is substituted with at least one of the following: -O-, -NH-, -N(R)- (where R represents a hydrocarbon group), -S-, -SO2-, etc.

[0053] Also, R 8 , R 9 , R 10 , R 11 and R 12 These may also form a ring structure together with the carbon atoms to which they are bonded.

[0054] R 8 , R 9 , R 10 , R 11 and R 12Particularly preferred are hydrogen atoms, methyl groups, and ethyl groups.

[0055] Examples of amine compounds represented by formula (2-2) include piperidine, 4-methyl-piperidine, 4-ethyl-piperidine, 4-isopropyl-piperidine, 4-(t-butyl)-piperidine, 2,6-dimethyl-piperidine, 2,6-diethyl-piperidine, 2,6-diisopropyl-piperidine, 2,6-di(t-butyl)-piperidine, 3,5-dimethyl-piperidine, 3,5-diethyl-piperidine, 3,5-diisopropyl-piperidine, and 3,5-di(t-butyl)-piperidine.

[0056] [Amine compounds represented by formula (2-3)] Formula (2-3): [ka] (R 13 , R 14 , R 15 and R 16 These are independent of each other. 13 , R 14 , R 15 and R 16 R represents a hydrogen atom or a hydrocarbon group. 13 , R 14 , R 15 and R 16 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and these heteroatoms may form a ring structure together with the carbon atoms to which they are bonded.

[0057] In formula (2-3), R 13 , R 14 , R 15 and R 16 They are independent of each other.

[0058] R 13 , R 14 , R 15 and R 16 is a hydrogen atom or a hydrocarbon group.

[0059] R 13 , R 14 , R 15 and R 16 If the group is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, preferably a hydrocarbon group having 1 to 12 carbon atoms that may be substituted with heteroatoms, more preferably a hydrocarbon group having 1 to 6 carbon atoms that may be substituted with heteroatoms, even more preferably a hydrocarbon group having 1 to 4 carbon atoms that may be substituted with heteroatoms, and even more preferably a hydrocarbon group having 1 to 2 carbon atoms that may be substituted with heteroatoms.

[0060] R 13 , R 14 , R 15 and R 16 However, examples of hydrocarbon groups that are not substituted with heteroatoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, s-butyl group, t-butyl group, pentyl group, neopentyl group, hexyl group, octyl group, benzyl group, and phenyl group, with methyl group, ethyl group, neopentyl group, and phenyl group being preferred, and methyl group and ethyl group being more preferred.

[0061] Also, R 13 , R 14 , R 15 and R 16 However, a hydrocarbon group that is substituted with a heteroatom is a hydrocarbon group in which at least one of the -CH2- atoms constituting the hydrocarbon group is substituted with at least one of the following: -O-, -NH-, -N(R)- (where R represents a hydrocarbon group), -S-, -SO2-, etc.

[0062] Also, R 13 , R 14 , R 15 and R 16 These may also form a ring structure together with the carbon atoms to which they are bonded.

[0063] R 13 , R 14 , R 15 and R 16Particularly preferred are hydrogen atoms, methyl groups, and ethyl groups.

[0064] Examples of amine compounds represented by formula (2-3) include piperazine, 2,6-dimethyl-piperazine, 2,6-diethyl-piperazine, 2,6-diisopropyl-piperazine, 2,6-di(t-butyl)piperazine, 2,6-diphenyl-piperazine, 2,6-dibenzyl-piperazine, 3,5-dimethyl-piperazine, 3,5-diethyl-piperazine, 3,5-diisopropyl-piperazine, 3,5-di(t-butyl)piperazine, 3,5-diphenyl-piperazine, and 3,5-dibenzyl-piperazine.

[0065] [Amine compounds represented by formula (2-4)] Formula (2-4): [ka] (R 17 , R 18 , R 19 and R 20 These are independent of each other. 17 , R 18 , R 19 and R 20 R represents a hydrogen atom or a hydrocarbon group. 17 , R 18 , R 19 and R 20 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and may form a ring structure together with the carbon and / or nitrogen atoms to which they are bonded.

[0066] In formula (2-4), R 17 , R 18 , R 19 and R 20 They are independent of each other.

[0067] R 17 , R 18 , R 19 and R 20 is a hydrogen atom or a hydrocarbon group.

[0068] R 17 , R 18 , R 19 and R 20 If the group is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with a heteroatom, preferably a hydrocarbon group having 1 to 12 carbon atoms that may be substituted with a heteroatom, more preferably a hydrocarbon group having 1 to 6 carbon atoms that may be substituted with a heteroatom, even more preferably a hydrocarbon group having 1 to 4 carbon atoms that may be substituted with a heteroatom, and particularly preferably a hydrocarbon group having 1 to 2 carbon atoms that may be substituted with a heteroatom.

[0069] R 17 , R 18 , R 19 and R 20 However, examples of hydrocarbon groups that are not substituted with heteroatoms include methyl group, ethyl group, propyl group, n-butyl group, s-butyl group, t-butyl group, pentyl group, neopentyl group, hexyl group, octyl group, benzyl group, and phenyl group, with methyl group, ethyl group, neopentyl group, and phenyl group being preferred, and methyl group and ethyl group being more preferred.

[0070] Also, R 17 , R 18 , R 19 and R 20 However, a hydrocarbon group that is substituted with a heteroatom is a hydrocarbon group in which at least one of the -CH2- atoms constituting the hydrocarbon group is substituted with at least one of the following: -O-, -NH-, -N(R)- (where R represents a hydrocarbon group), -S-, -SO2-, etc.

[0071] Also, R 17 , R 18 , R 19 and R 20 These may form a ring structure together with the carbon and / or nitrogen atoms to which they are bonded.

[0072] R 17 , R 18 , R 19 and R 20The ring structure formed together with the bonded carbon and / or nitrogen atoms is R 18 and R 18 The nitrogen atom bonded to R 19 and R 19 A 6-8 membered ring structure formed by the bonded carbon atoms, R 17 and R 17 The nitrogen atom bonded to R 19 The carbon atom to which R is bonded 20 and R 20 A 5-7 membered ring structure is formed by the nitrogen atoms to which it is bonded, and the aforementioned R 18 and R 18 The nitrogen atom bonded to R 19 and R 19 A 6-8 membered ring is formed by the carbon atoms to which it is bonded, and the aforementioned R 17 and R 17 The nitrogen atom bonded to R 19 The carbon atom to which R is bonded 20 and R 20 These include ring structures in which a 5- to 7-membered ring formed by bonded nitrogen atoms is fused with the nitrogen atom.

[0073] R 17 , R 18 , R 19 and R 20 Particularly preferred are hydrogen atoms, methyl groups, and ethyl groups.

[0074] Also, R 17 , R 18 , R 19 and R 20 Preferably, R is the ring structure formed together with the carbon and / or nitrogen atoms to which it is bonded. 18 and R 18 The nitrogen atom bonded to R 19 and R 19 A 7-membered ring is formed by the carbon atoms to which R is bonded, 17 and R 17 The nitrogen atom bonded to R 19 The carbon atom to which R is bonded 20 and R 20 It is a ring structure in which a 6-membered ring formed by bonded nitrogen atoms is fused with another ring.

[0075] Examples of amine compounds represented by formula (2-4) include imidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole, diazabicycloundecene (1,8-diazabicyclo[5.4.0-7-undecene]), and 1,5-diazabicyclo[4.3.0]-5-nonene.

[0076] In the blocked polyisocyanate composition of the present invention, the amount of the amine compound represented by formulas (2-1) to (2-4) relative to the blocked polyisocyanate compound is determined by the required physical properties and is not particularly limited. Typically, with the amount of effective isocyanate groups in the blocked polyisocyanate compound being 100 mol, the amount of the amine compound is in the range of 5 to 25 mol%, preferably in the range of 10 to 20 mol%, and more preferably in the range of 13 to 18 mol%. The effective isocyanate groups in the blocked polyisocyanate compound refer to the isocyanate groups that are regenerated when the blocking agent is dissociated from the blocked polyisocyanate compound.

[0077] <Curable resin composition> The curable resin composition of the present invention comprises the block polyisocyanate composition of the present invention and a compound having an isocyanate-reactive group.

[0078] <Compounds containing isocyanate-reactive groups> Compounds having isocyanate-reactive groups include compounds having two or more active hydrogen groups, such as polyols, polyamines, and alkanolamines. These compounds having isocyanate-reactive groups may also be a mixture of two or more types. The compound having an isocyanate-reactive group is preferably a polyol or a polyamine.

[0079] [Polyol] In the present invention, a polyol is a compound having two or more hydroxyl groups. Examples include polyester polyols, polyether polyols, acrylic polyols, polyolefin polyols, and fluorine polyols. Among these, acrylic polyols are preferred as polyols from the viewpoint of weather resistance, chemical resistance, and hardness. Alternatively, polyester polyols are preferred as polyols from the viewpoint of mechanical strength and oil resistance. These polyols may also be mixtures of two or more types.

[0080] [Polyester polyol] Polyester polyols can be obtained, for example, by condensing a dibasic acid (either alone or a mixture of two or more) with a polyhydric alcohol (either alone or a mixture of two or more).

[0081] Examples of dibasic acids used in polyester polyols include succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, and carboxylic acids such as 1,4-cyclohexanedicarboxylic acid.

[0082] Examples of polyhydric alcohols used in polyester polyols include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, trimethylolpropane, glycerin, pentaerythritol, 2-methylolpropanediol, and ethoxylated trimethylolpropane.

[0083] Specific methods for producing polyester polyols include, for example, mixing the above-mentioned dibasic acid and polyhydric alcohol and heating at approximately 160-220°C to carry out a condensation reaction. Alternatively, polycaprolactones, such as those obtained by ring-opening polymerization of lactones such as ε-caprolactone using a polyhydric alcohol, can also be used as polyester polyols. These polyester polyols can be modified using aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and polyisocyanates obtained therefrom. In particular, from the viewpoint of weather resistance and resistance to yellowing, it is preferable to modify polyester polyols using aliphatic diisocyanates, alicyclic diisocyanates, and polyisocyanates obtained therefrom.

[0084] When the curable resin composition of the present invention is used as a water-based paint, some carboxylic acids derived from dibasic acids, etc., in the polyester polyol can be left in place and neutralized with a base such as an amine or ammonia to make the polyester polyol a water-soluble or water-dispersible resin.

[0085] [Polyether polyol] Examples of polyether polyols include aliphatic amine polyols, aromatic amine polyols, Mannich polyols, polyhydric alcohols, polyhydric phenols, bisphenols and other active hydrogen compounds, and compounds obtained by adding alkylene oxides to these. These polyether polyols may also be mixtures of two or more types.

[0086] Examples of aliphatic amine polyols include alkylenediamine polyols and alkanolamine polyols. These polyol compounds are polyfunctional polyol compounds with terminal hydroxyl groups obtained by ring-opening addition of at least one cyclic ether such as ethylene oxide or propylene oxide to an alkylenediamine or alkanolamine as an initiator. Known compounds can be used without limitation as alkylenediamines. Specifically, alkylenediamines with 2 to 8 carbon atoms, such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, and neopentyldiamine, are preferred. These aliphatic amine polyols may also be mixtures of two or more types.

[0087] Aromatic amine polyols are polyfunctional polyether polyol compounds with terminal hydroxyl groups obtained by ring-opening and adding at least one cyclic ether such as ethylene oxide or propylene oxide to an aromatic diamine as an initiator. Any known aromatic diamine can be used as an initiator without limitation. Specifically, examples include 2,4-toluenediamine, 2,6-toluenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylmethane, p-phenylenediamine, o-phenylenediamine, and naphthalenediamine. Among these, the use of toluenediamine (2,4-toluenediamine, 2,6-toluenediamine, or a mixture thereof) is particularly preferred. These aromatic amine polyols may also be mixtures of two or more types.

[0088] Mannich polyols are active hydrogen compounds obtained by the Mannich reaction of phenol and / or its alkyl-substituted derivatives, formaldehyde and alkanolamines, or polyol compounds obtained by ring-opening addition polymerization of these compounds with at least one of ethylene oxide or propylene oxide. These Mannich polyols may also be mixtures of two or more types.

[0089] Examples of polyhydric alcohols include dihydric alcohols (e.g., ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, neopentyl glycol, etc.) and trihydric or higher alcohols (e.g., glycerin, trimethylolpropane, pentaerythritol, methyl glucoside, sorbitol, sucrose, etc.). These polyhydric alcohols may also be mixtures of two or more types.

[0090] Examples of polyhydric phenols include pyrogallol and hydroquinone. These polyhydric phenols may also be a mixture of two or more types.

[0091] Examples of bisphenols include bisphenol A, bisphenol S, bisphenol F, and low-level condensates of phenol and formaldehyde. These bisphenols may also be mixtures of two or more types.

[0092] For example, one of the following methods 1 to 3 can be used to produce polyether polyols.

[0093] Method 1: A method for obtaining polyether polyols by randomly or block adding an alkylene oxide alone or a mixture to a polyhydric hydroxy compound alone or a mixture using a catalyst.

[0094] Examples of catalysts used in method 1 include hydroxides (lithium, sodium, potassium, etc.), strongly basic catalysts (alkoxides, alkylamines, etc.), and complex metal cyanide compounds (metallic porphyrins, zinc hexacyanocobaltate complexes, etc.).

[0095] Examples of alkylene oxides used in manufacturing method 1 include ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, and styrene oxide.

[0096] Examples of polyhydric hydroxy compounds used in method 1 include the following (i) to (vi). (i) Diglycerin, ditrimethylolpropane, pentaerythritol, dipentaerythritol, etc. (ii) Sugar alcohol compounds such as erythritol, D-threitol, L-arabinitol, ribitol, xylitol, sorbitol, mannitol, galactitol, and rhamnitol. (iii) Monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbose, rhamnose, fucose, and ribodesose. (iv) Disaccharides such as trehalose, sucrose, maltose, cellobiose, genthiobiose, lactose, and melibiose. (v) Trisaccharides such as raffinose, gentianose, and meletitose. (vi) Tetrasaccharides such as stachyose.

[0097] Method 2: A method for obtaining polyether polyols by reacting a polyamine compound with an alkylene oxide. Examples of polyamine compounds used in method 2 include ethylenediamines. Examples of alkylene oxides used in method 2 include those exemplified in method 1.

[0098] Method 3: A method for obtaining so-called polymer polyols by polymerizing acrylamide or the like using polyether polyols obtained by Method 1 or Method 2 as a medium.

[0099] [Acrylic polyol] Acrylic polyols can be obtained, for example, by polymerizing a polymerizable monomer having one or more active hydrogen atoms in one molecule, or by copolymerizing a polymerizable monomer having one or more active hydrogen atoms in one molecule with, if necessary, another monomer copolymerizable with the polymerizable monomer.

[0100] Examples of polymerizable monomers having one or more active hydrogen atoms in a single molecule include (i) to (vi) below. These may be used individually or in combination of two or more types. (i) Acrylic acid esters having active hydrogen, such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxybutyl acrylate. (ii) Methacrylic acid esters having active hydrogen, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, and 4-hydroxybutyl methacrylate. (iii) (meth)acrylic acid esters having polyvalent active hydrogen, such as (meth)acrylic acid monoesters of triols like glycerin and trimethylolpropane. (iv) Monoethers of polyether polyols (e.g., polyethylene glycol, polypropylene glycol, polybutylene glycol, etc.) and (meth)acrylic acid esters having the above-mentioned active hydrogen. (v) Adducts of glycidyl (meth)acrylate with monobasic acids (e.g., acetic acid, propionic acid, p-tert-butylbenzoic acid, etc.). (vi) Adducts obtained by ring-opening polymerization of lactones (e.g., ε-caprolactam, γ-valerolactone, etc.) to the active hydrogen of the above-mentioned (meth)acrylic acid esters having active hydrogen.

[0101] Other monomers copolymerizable with the polymerizable monomer include, for example, (i) to (iv) below. These may be used individually or in combination of two or more. (i) (meth)acrylic acid esters such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, and glycidyl methacrylate. (ii) Unsaturated amides such as acrylic acid, methacrylic acid, maleic acid, itaconic acid (unsaturated carboxylic acids such as acrylamide, N-methylolacrylamide, and diacetoneacrylamide). (iii) Vinyl monomers having hydrolyzable silyl groups, such as vinyltrimethoxysilane, vinylmethyldimethoxysilane, and γ-(meth)acrylopropyltrimethoxysilane. (iv) Other polymerizable monomers such as styrene, vinyltoluene, vinyl acetate, acrylonitrile, and dibutyl fumarate.

[0102] Specific methods for producing acrylic polyols include, for example, a method in which the above-mentioned monomer components are solution polymerized in the presence of known radical polymerization initiators such as peroxides and azo compounds, and then diluted with an organic solvent as necessary to obtain an acrylic polyol.

[0103] When the curable resin composition of the present invention is used as a water-based coating, a water-based acrylic polyol can be produced by using known methods such as solution polymerization of the above monomer components to convert them into an aqueous layer, or emulsion polymerization. In this case, the acidic portion, such as carboxylic acid-containing monomers like acrylic acid and methacrylic acid, or sulfonic acid-containing monomers, can be neutralized with amines or ammonia to impart water-soluble or water-dispersible properties to the acrylic polyol.

[0104] [Polyolefin polyol] Examples of polyolefin polyols include polybutadiene having two or more hydroxyl groups, hydrogenated polybutadiene having two or more hydroxyl groups, and hydrogenated polyisoprene having two or more hydroxyl groups. Furthermore, in polyolefin polyols, the number of hydroxyl groups is preferably three, as this allows for higher coating film strength.

[0105] [Fluorine polyol] In the present invention, "fluorine polyol" means a polyol containing fluorine in its molecule. Specific examples of fluorine polyols include copolymers of fluoroolefins, cyclovinyl ethers, hydroxyalkyl vinyl ethers, and vinyl monocarboxylate esters, as disclosed in Japanese Patent Publication No. 57-34107 and Japanese Patent Publication No. 61-275311, among others.

[0106] [Hydroxyl value and acid value of polyols] The lower limit of the hydroxyl value of the polyol is preferably 10 mg KOH / g or more, more preferably 20 mg KOH / g or more, and even more preferably 30 mg KOH / g or more. On the other hand, there are no specific limitations on the upper limit of the hydroxyl value of polyols; for example, it is sufficient if it is 300 mg KOH / g or less. In other words, the hydroxyl value of the polyol is preferably 10 mg KOH / g or more and 300 mg KOH / g or less, more preferably 20 mg KOH / g or more and 300 mg KOH / g or less, and even more preferably 30 mg KOH / g or more and 300 mg KOH / g or less.

[0107] Furthermore, the acid value of the polyol is preferably 0 mg KOH / g or more and 30 mg KOH / g or less. The hydroxyl value and acid value can be measured in accordance with JIS K1557.

[0108] The molar equivalent ratio (NCO / OH) of the isocyanate groups of the above-described blocked polyisocyanate composition to the hydroxyl groups of the polyol is preferably 0.2 or more and 5.0 or less, more preferably 0.4 or more and 3.0 or less, and even more preferably 0.5 or more and 2.0 or less.

[0109] [Polyamines] Polyamines used in the present invention include those having two or more primary or secondary amino groups in one molecule, and among these, those having three or more primary or secondary amino groups in one molecule are preferred.

[0110] Specific examples of polyamines used in the present invention include diamines such as ethylenediamine, propylenediamine, butylenediamine, triethylenediamine, hexamethylenediamine, 4,4'-diaminodicyclohexylmethane, piperazine, 2-methylpiperazine, and isophoronediamine; chain polyamines having three or more amino groups such as bishexamethylenetriamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentamethylenehexamine, and tetrapropylenepentamine; and cyclic polyamines such as 1,4,7,10,13,16-hexazacyclooctadecane, 1,4,7,10-tetraazacyclodecane, 1,4,8,12-tetraazacyclopentadecane, and 1,4,8,11-tetraazacyclotetradecane.

[0111] [Alkanolamines] In this invention, the term "alkanolamine" refers to a compound having an amino group and a hydroxyl group in one molecule. Examples of alkanolamines include monoethanolamine, diethanolamine, aminoethylethanolamine, N-(2-hydroxypropyl)ethylenediamine, mono-, di-(n- or iso-)propanolamine, ethylene glycol-bis-propylamine, neopentanolamine, and methylethanolamine.

[0112] [Mixing ratio of block polyisocyanate composition to compound having an isocyanate-reactive group] In the curable resin composition of the present invention, the blending ratio of the blocked polyisocyanate composition and the compound having isocyanate-reactive groups is determined by the required physical properties and is not particularly limited. Typically, the ratio of [amount of active isocyanate groups of the blocked polyisocyanate compound in the blocked polyisocyanate composition (mol)] / [amount of active hydrogen groups of the compound having isocyanate-reactive groups (mol)] is in the range of 0.2 to 5, and preferably in the range of 0.5 to 3. The effective isocyanate groups of the blocked polyisocyanate compound refer to the isocyanate groups that are regenerated when the blocking agent is dissociated from the blocked polyisocyanate compound.

[0113] [Curing catalyst] The curable resin composition of the present invention may further contain a curing catalyst in addition to a block polyisocyanate composition and a compound having an isocyanate-reactive group.

[0114] The curing catalyst is not particularly limited and may include, for example, tin compounds such as dibutyltin dilaurate, dibutyltin di-2-ethylhexanate, dioctyltin dilaurate, dibutyltin diacetate, dibutyltin dioxide, dioctyltin dioxide, tin acetylacetonate, tin acetate, tin octoate, tin laurate, bismuth compounds such as bismuth octanoate, bismuth 2-ethylhexanoate, bismuth naphthenate, bismuth acetylacetonate, tetra-n-butyl titanate, tetraisopodium titanate Ropil, titanium compounds such as titanium terephthalate, triethylamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylpropylenediamine, N,N,N',N”,N”-pentamethyldiethylenetriamine, N,N,N',N”,N”-pentamethyldipropylenetriamine, N,N,N',N'-tetramethylguanidine, 1,3,5-tris(N,N-dimethylaminopropyl)hexahydro-S-triazine, 1,4-diazabicyclo[2.2.2]octa Examples include tertiary amine compounds such as (DABCO), 1,8-diazabicyclo[5.4.0]undecene-7, triethylenediamine, N,N,N',N'-tetramethylhexamethylenediamine, N-methyl-N'-(2-dimethylaminoethyl)piperazine, N,N'-dimethylpiperazine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, bis(2-dimethylaminoethyl)ether, 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, and 1-dimethylaminopropylimidazole; tetraalkylammonium halides such as tetramethylammonium chloride; tetraalkylammonium hydroxides such as tetramethylammonium hydroxide; and quaternary ammonium organic acid salts such as tetramethylammonium-2-ethylhexanoate, 2-hydroxypropyltrimethylammonium forate, and 2-hydroxypropyltrimethylammonium-2-ethylhexanoate.

[0115] Preferably, the curing catalyst is dibutyltin dilaurate or bismuth 2-ethylhexanoate.

[0116] Furthermore, the curable resin composition of the present invention may optionally contain a melamine-based curing agent such as a fully alkyl type, methylol type, or alkylamino group type alkyl.

[0117] In the curable resin composition of the present invention, the content of the curing catalyst is preferably 0.01 to 20% by weight relative to the block polyisocyanate, and more preferably 0.1 to 10% by weight.

[0118] The blocked isocyanate composition and the curable resin composition of the present invention may contain an organic solvent.

[0119] The organic solvent is preferably one that is compatible with the block polyisocyanate composition and the curable resin composition of the present invention.

[0120] Examples of organic solvents include hydrocarbons such as benzene, toluene, xylene, cyclohexane, mineral spirits, and naphtha; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; esters such as ethyl acetate, butyl acetate, and cellosolve acetate; alcohols such as methanol, ethanol, 2-propanol, butanol, 2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol; polyhydric alcohols such as ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, and glycerin; and water. These solvents may be used individually or in combination of two or more.

[0121] Furthermore, the curable resin composition of the present invention can be used as an aqueous thermosetting resin composition dissolved or dispersed in water. When the curable resin composition of the present invention is used as an aqueous thermosetting resin composition, a surfactant or a solvent that tends to be miscible with water may be used with the block polyisocyanate composition of the present invention to improve the compatibility of the curable resin composition with water.

[0122] Examples of surfactants include anionic surfactants such as aliphatic soaps, rosinate soaps, alkyl sulfonates, dialkylaryl sulfonates, alkyl sulfosuccinates, polyoxyethylene alkyl sulfates, and polyoxyethylene alkylaryl sulfates, as well as nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, and polyoxyethylene oxypropylene block copolymers.

[0123] Solvents that tend to be miscible with water include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, isobutanol, butyl glycol, N-methylpyrrolidone, butyl diglycol, or butyl diglycol acetate.

[0124] Among the above solvents, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, isobutanol, butyl glycol, N-methylpyrrolidone, and butyl diglycol are preferred, and diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol dimethyl ether, and dipropylene glycol dimethyl ether are more preferred. These solvents may be used individually or in combination of two or more.

[0125] Furthermore, when the curable resin composition of the present invention is used as an aqueous thermosetting resin composition, solvents such as esters like ethyl acetate, n-butyl acetate, and cellosolve acetate are undesirable because the solvent itself may undergo hydrolysis during storage.

[0126] The block polyisocyanate composition and curable resin composition of the present invention may, if necessary, contain known additives, pigments, etc., commonly used in the art, and may also be used in mixture with known block polyisocyanates.

[0127] The additives are not particularly limited and include a variety of additives such as UV absorbers, color inhibitors, antioxidants, leveling agents, defoamers, rheology control agents, thixotropy imparters / thickeners, light stabilizers, plasticizers, surfactants, coupling agents, flame retardants, rust inhibitors, fluorescent whitening agents, and pigment dispersants.

[0128] For example, UV absorbers include hindered amines, benzotriazoles, and benzophenones. Anti-coloring agents include perchlorates and hydroxylamines. Antioxidants include hindered phenols, phosphorus, sulfur, and hydrazides.

[0129] Pigments are not particularly limited and include organic pigments, inorganic pigments, carbon-based pigments, metallic foil pigments, and rust-preventive pigments. For example, organic pigments include quinacridone-based, azo-based, and phthalocyanine-based pigments. Inorganic pigments include titanium dioxide, barium sulfate, calcium carbonate, and silica.

[0130] Known blocked polyisocyanates include, for example, blocked polyisocyanates obtained by reacting a polyisocyanate with a known blocking agent. Known blocking agents include, for example, phenolic compounds such as phenol, thiophenol, methylthiophenol, xylenol, cresol, resorcinol, nitrophenol, and chlorophenol; oxime compounds such as acetone oxime, methyl ethyl ketone oxime, and cyclohexanone oxime; methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, t-butyl alcohol, t-pentanol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, and benzyl Examples include alcohol compounds such as chloroal alcohols, pyrazole compounds such as 3,5-dimethylpyrazole and 1,2-pyrazole, triazole compounds such as 1,2,4-triazole, halogen-substituted alcohol compounds such as ethylene chlorohydrin and 1,3-dichloro-2-propanol, lactam compounds such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propyllactam, and active methylene compounds such as methyl acetoacetate, ethyl acetoacetate, acetylacetone, methyl malonate, and ethyl malonate. Other examples include imide compounds, mercaptan compounds, imine compounds, urea compounds, and diaryl compounds.

[0131] [Storage method] The block polyisocyanate composition and the curable resin composition of the present invention can be stored at temperatures between 0°C and 40°C.

[0132] [Curing method] The curing method for the curable resin composition of the present invention is a method of heating a curable resin composition containing the block polyisocyanate composition of the present invention and a compound having an isocyanate reactive group, or a curable resin composition further containing a curing catalyst.

[0133] The heating temperature varies depending on the block polyisocyanate compound and amine compound (formulas (2-1) to (2-4)) in the block polyisocyanate composition used, but can be approximately 60 to 250°C, preferably 80 to 200°C. The reaction time can be approximately 30 seconds to 5 hours, preferably 1 minute to 60 minutes. The cured product of the present invention can be produced by curing the curable resin composition of the present invention using the curing method described above.

[0134] [Application] The block polyisocyanate composition, curable resin composition, and cured product of the present invention can be used in paints, coatings, inks, adhesives, sealants, encapsulants, sealing materials, molding materials, and the like. For example, as a paint, it can be used for automobiles, buildings, metal products such as steel furniture, woodworking products such as musical instruments, machinery and vehicles such as construction equipment, building materials such as window frames, and electrical appliances such as office equipment. Furthermore, it can be used as a coating material for artificial leather and rubber rolls, as a sealing material for electronic components, as a sealing material for automobiles and buildings, and as a molding material for 3D printers. [Examples]

[0135] The present invention will be described in more detail using manufacturing examples and embodiments, but the present invention is not limited to these embodiments.

[0136] (1) Infrared spectroscopy conditions Equipment: FT-IR-6600 manufactured by JASCO Corporation Measurement method: Total internal reflection (crystal: germanium) Total number of times: 16 (2) Gas chromatography Equipment: Shimadzu GC-2030 Detector: FID Column: DB-624 / Inner diameter: 0.32 mm, Film thickness: 1.80 μm, Length: 30.0 m Oven temperature: 50 °C (10 minutes) → 10 °C / min → 250 °C (5 minutes) INJ: 150 °C DET: 260 °C Carrier gas: Helium Linear velocity: 48.5 cm / sec Split ratio: 50.0 Injection volume: 1.0 μL

[0137] Calculation method of effective NCO group content (%) The effective NCO group content (%) here quantifies the amount of blocked isocyanate groups that can react with isocyanate-reactive groups present in the blocked polyisocyanate compound, is expressed as the mass (%) of isocyanate groups, and is calculated by the following formula. Effective NCO group content (%) = { (Solid content (mass (%)) of the blocked polyisocyanate compound) × (Mass of the polyisocyanate compound used in the reaction × NCO group content (%) of the polyisocyanate compound used in the reaction)} / (Mass of the blocked polyisocyanate compound) / {Solid content (%)} When diluted with a solvent or the like, the value in the diluted state is described.

[0138] Calculation method of solid content An absolute calibration curve of methyl isobutyl ketone (hereinafter referred to as MIBK) was created by gas chromatography, the content of MIBK in the sample was determined, and the solid content (%) obtained by removing MIBK from the total amount was calculated.

[0139] Composition of the curable resin composition Blocked polyisocyanate compound, compound having isocyanate-reactive groups, curing catalyst, and amine compound were added so that the ratio of active NCO groups (mol): hydroxyl groups (mol): curing catalyst (mol): amine compound (mol) = 1.00:0.95:0 to 0.10:0.15. MIBK was then added so that the ratio of solids (g) of the blocked polyisocyanate compound to solvent (g) = 1.0:1.0. Note that the solvent here includes the solvent used to dilute the blocked polyisocyanate compound. The active NCO groups (mol) and hydroxyl groups (mol) were calculated using the following formula. Effective NCO groups (mol) = Amount of block polyisocyanate compound charged (g) × Effective NCO group content of block polyisocyanate compound (%) ÷ 420² Hydroxyl groups (mol) = Amount of polyol added (g) × Hydroxyl value of polyol (mgKOH / g) ÷ 56.1

[0140] Manufacturing Example 1: Synthesis of MIBK solution (A-1) of tert-butylethylamine (hereinafter referred to as tBEA) block of biuret-type HDI. 500.0 g of biuret-type HDI (Desmodule N3200A, NCO group content: 22.8%), manufactured by Sumika Covestro Urethane Co., Ltd. (NCO groups: 2.59 mol) and 350.0 g of MIBK were charged into a nitrogen-purged 2 L three-port reactor. Subsequently, 274.0 g (2.71 mol) of tBEA (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise at 25°C, stirred at 25°C for 2 hours, and infrared spectroscopy analysis revealed that the isocyanate group was 2270 cm⁻¹. -1 The disappearance of the infrared absorption peak in the vicinity was confirmed. The obtained reaction solution was concentrated under reduced pressure, and tBEA and some MIBK were removed to obtain 1040.39 g of MIBK solution (A-1) of the tBEA block of biuret-type HDI. The solid content of the obtained tBEA block (A-1) of biuret-type HDI was 72%, and the effective NCO group content was 10%.

[0141] Example 1 To prepare the curable resin composition, the following ingredients were added: 5.00 g of the tBEA block (A-1) of the biuret-type HDI obtained in Production Example 1, 13.6 g of acrylic polyol (Acrylit 6AN6000, manufactured by Taisei Fine Chemical Co., Ltd.), 0.387 g of dibutyltin dilaurate (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.180 g of tBEA (manufactured by Tokyo Chemical Industry Co., Ltd.). Furthermore, 2.20 g of MIBK was added so that the amount of solvent was 1.0 times the weight of the block polyisocyanate compound, and the mixture was stirred for 30 minutes to prepare the curable resin composition. The prepared curable resin composition was packed 80% into 4 mL screw-cap tubes and stored in a nitrogen atmosphere for one week. After one week, the curable resin composition was evaluated based on whether it had hardened (indicating no storage stability) or remained liquid (indicating storage stability). The results are shown in Table 1. The evaluation results are indicated by "○" for storage stability and "×" for storage instability.

[0142] Examples 2-5, Comparative Examples 1-4 In Example 1, a curable resin composition was prepared in the same manner as in Example 1, except that the polyol compound, curing catalyst, and amine compound were changed to those shown in Table 1. In Examples 4 and 5 and Comparative Examples 3 and 4, storage stability was evaluated in the same manner as in Example 1, except that the storage temperature and storage period were changed to those shown in Table 1. The results are shown in Table 1.

[0143] [Table 1] A-1: tBEA block body of biuret-type HDI obtained in manufacturing example 1 B-1: Acrylic polyol (Acrit 6AN6000, manufactured by Taisei Fine Chemical Co., Ltd.) B-2: Polyester polyol (P510, manufactured by Kuraray Co., Ltd.) C-1: Dibutyltin dilaurate C-2:2-Bismuth ethylhexanoate D-1: tBEA D-2: Diisopropylamine

[0144] Based on the results of Examples 1-5 and Comparative Examples 1-4, it was found that the curable resin composition containing the block polyisocyanate compound and amine compound of the present invention exhibits superior storage stability for 1 week to 1 month under the same storage conditions compared to the curable resin composition not containing the amine compound.

Claims

1. A blocked polyisocyanate composition comprising a blocked polyisocyanate compound in which the isocyanate group of a polyisocyanate compound is blocked by a secondary amine compound represented by the following formula (1), and an amine compound represented by at least one formula selected from the group consisting of the following formulas (2-1), (2-2), (2-3), and (2-4). Formula (1): 【Chemistry 1】 (wherein, R 1 , R 2 , R 3 , R 4 and R 5 are each independent. R 1 , R 2 and R 3 represent a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with heteroatoms. R 4 and R 5 represent a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with heteroatoms or a hydrogen atom. R 1 , R 2 , R 3 , R 4 and R 5 may together with the carbon atom to which they are attached form a ring structure.) Formula (2-1): 【Chemistry 2】 (R 6 and R 7 These are independent of each other. 6 and R 7 R represents a hydrocarbon group having 1 to 20 carbon atoms, which may be substituted with heteroatoms. 6 and R 7 They may also form a ring structure together with the nitrogen atom to which they are bonded. Formula (2-2): 【Transformation 3】 (R 8 , R 9 , R 10 , R 11 and R 12 These are independent of each other. 8 , R 9 , R 10 , R 11 and R 12 R represents a hydrogen atom or a hydrocarbon group. 8 , R 9 , R 10 , R 11 and R 12 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and these heteroatoms may form a ring structure together with the carbon atoms to which they are bonded. Formula (2-3): 【Chemistry 4】 (R 13 , R 14 , R 15 and R 16 These are independent of each other. 13 , R 14 , R 15 and R 16 R represents a hydrogen atom or a hydrocarbon group. 13 , R 14 , R 15 and R 16 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and these heteroatoms may form a ring structure together with the carbon atoms to which they are bonded. Formula (2-4): 【Transformation 5】 (R 17 , R 18 , R 19 and R 20 These are independent of each other. 17 , R 18 , R 19 and R 20 R represents a hydrogen atom or a hydrocarbon group. 17 , R 18 , R 19 and R 20 If it is a hydrocarbon group, it is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with heteroatoms, and may form a ring structure together with the carbon and / or nitrogen atoms to which they are bonded.

2. The block polyisocyanate composition according to claim 1, wherein the polyisocyanate compound is at least one polyisocyanate selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates and aromatic aliphatic polyisocyanates, or a modified polyisocyanate formed from at least one selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates and aromatic aliphatic polyisocyanates.

3. R of the secondary amine compound represented by formula (1) 1 , R 2 and R 3 R is a hydrocarbon group having 1 to 2 carbon atoms. 4 and R 5 The block polyisocyanate composition according to claim 1, wherein is a hydrocarbon group having 1 to 2 carbon atoms or a hydrogen atom.

4. A curable resin composition comprising a block polyisocyanate composition according to any one of claims 1 to 3, and a compound having an isocyanate-reactive group.

5. The curable resin composition according to claim 4, wherein the compound having an isocyanate reactive group is a polyol compound or a polyamine compound.

6. A curable resin composition comprising the curable resin composition according to claim 4 and a curing catalyst.

7. A cured product obtained by curing the curable resin composition according to claim 6.

Images