End-capped polyisocyanate composition, hydrophilic polyisocyanate composition, resin composition, resin film, and laminate

Abstract

The present application relates to a capped polyisocyanate composition, a hydrophilic polyisocyanate composition, a resin composition, a resin film, and a laminate. The capped polyisocyanate composition comprises an anionic dispersant and a capped polyisocyanate derived from a polyisocyanate and one or more kinds of a capping agent comprising (A) a compound represented by the following general formula (I) (in the formula, R 11 represents an alkoxy group or the like, R 12 represents a hydrogen atom or the like, R 13 and R 14 represent an alkyl group or the like) or (B) a compound having a heterocycle containing one or more nitrogens, a water solution of the anionic dispersant containing water and 0.1% by mass of the anionic dispersant with respect to the total mass of the water solution has a surface tension of 32 mN / m or more and 51 mN / m or less at 25°C as measured by the Wilhelmy method, and when the capping agent is (B) a compound having a heterocycle containing one or more nitrogens, the capped polyisocyanate composition further comprises a carboxylate salt.

Description

[0001] This application is a divisional application of the application filed on July 31, 2020, with application number 202010760513.8 and invention title "End-capped polyisocyanate composition, hydrophilic polyisocyanate composition, resin composition, resin film and laminate". Technical Field

[0002] This invention relates to end-capped polyisocyanate compositions, hydrophilic polyisocyanate compositions, resin compositions, resin films, and laminates. Background Technology

[0003] Previously, polyurethane resin coatings have exhibited excellent abrasion resistance, chemical resistance, and stain resistance. In particular, polyurethane resin coatings using polyisocyanates derived from aliphatic or cyclic diisocyanates demonstrate superior weather resistance, leading to increasing demand. However, polyurethane resin coatings are typically two-component, making their use extremely inconvenient. Specifically, typical polyurethane resin coatings consist of two components: a polyol and a polyisocyanate. These components must be stored separately and mixed during application. Furthermore, there is a problem that the coating gels rapidly upon mixing, rendering it unusable. This issue makes polyurethane resin coatings extremely difficult to use in automated painting processes, such as automotive or low-voltage electrical coatings. Additionally, isocyanates readily react with water, preventing their use in water-based coatings such as electrodeposition coatings. Moreover, the use of coatings containing isocyanates necessitates thorough cleaning of the painting machine and painting tank at the end of the job, significantly reducing work efficiency.

[0004] To address the aforementioned issues, previously proposed methods have involved using terminally capped polyisocyanates where all active isocyanate groups are capped with a capping agent. These capped polyisocyanates do not react with polyols at room temperature. However, by heating, the capping agent is dissociated, allowing the active isocyanate groups to regenerate and react with the polyol, resulting in a cross-linking reaction, thus mitigating the aforementioned problems. Therefore, various capping agents have been studied, with phenol and methyl ethyl ketone oxime being representative examples.

[0005] However, the use of terminated polyisocyanates obtained using these terminators typically requires high baking temperatures above 140°C. The need for high-temperature baking is not only energy-intensive but also requires heat resistance from the substrate, which is a major reason for its limited applications.

[0006] On the other hand, as low-temperature baking-type end-capped polyisocyanates, research has been conducted on end-capped polyisocyanates obtained using active methylene compounds such as acetoacetate and malonic acid ester. For example, Patent Documents 1 and 2 propose end-capped polyisocyanate compositions that cure at 90°C.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 2002-322238

[0010] Patent Document 2: Japanese Patent Application Publication No. 2006-335954 Summary of the Invention

[0011] The problem the invention aims to solve

[0012] However, in recent years, from the perspective of protecting the Earth's environment, there has been a strong demand for applications in plastics with low heat resistance, and there is an urgent need for end-capped polyisocyanate compositions that cure at temperatures below 90°C. Under these conditions, products that exhibit good dispersibility during mixing, do not gel or excessively thicken during storage, and have good curability below 80°C, compared to aqueous polyols with hydroxyl groups (water-dispersible polyols), are still unknown.

[0013] The present invention was made in view of the above circumstances, and provides a capped polyisocyanate composition that has good storage stability when made into a resin composition and good curability at a low temperature of about 80°C when made into a resin film, as well as a resin composition, resin film and laminate using the aforementioned capped polyisocyanate composition.

[0014] In addition, a hydrophilic polyisocyanate composition with good water dispersibility and excellent hardness when formed into a resin film is provided, as well as a capped polyisocyanate composition, a resin composition and a resin film using the aforementioned hydrophilic polyisocyanate composition.

[0015] Solution for solving the problem

[0016] The present invention includes the following solutions.

[0017] (1) A capped polyisocyanate composition comprising:

[0018] End-capped polyisocyanates derived from polyisocyanates and one or more end-capping agents; and

[0019] Anionic dispersants

[0020] The aforementioned capping agent comprises (A) a compound represented by the following general formula (I) or (B) a compound having a heterocycle containing one or more nitrogen atoms.

[0021] The surface tension of the aforementioned anionic dispersant, as determined by the Wilhelmy method, comprising water and an aqueous solution of the aforementioned anionic dispersant at a total mass of 0.1% relative to the aqueous solution, is 32 mN / m or more and 51 mN / m or less at 25°C.

[0022] When the aforementioned capping agent comprises (B) a compound having a heterocycle containing one or more nitrogen atoms, the aforementioned capped polyisocyanate composition further comprises a carboxylate.

[0023]

[0024] (In the aforementioned general formula (I), R) 11 The amino group is a hydroxyl group; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; an amino group optionally containing one or more substituents selected from the group consisting of hydroxyl and alkyl groups; an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an alkoxy group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. Wherein, two of the aforementioned amino groups may be linked together to form a ring.

[0025] R 12 R 13 and R 14 Each is independently a hydrogen atom; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. The aforementioned amino groups may optionally have two of the aforementioned substituents linked together to form a ring. Wherein, R is absent. 12 R 13 and R 14 (The case where two or more atoms are hydrogen atoms.)

[0026] (2) A capped polyisocyanate composition comprising:

[0027] End-capped polyisocyanates derived from polyisocyanates and one or more end-capping agents; and

[0028] Anionic dispersants

[0029] The aforementioned capping agent comprises a compound represented by the following general formula (I).

[0030] The surface tension of the aforementioned anionic dispersant, as determined by the Wilhelmy method, comprising water and an aqueous solution of the aforementioned anionic dispersant at a total mass of 0.1% relative to the aqueous solution, is 32 mN / m or more and 51 mN / m or less at 25°C.

[0031]

[0032] (In the aforementioned general formula (I), R)11 The amino group is a hydroxyl group; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; an amino group optionally containing one or more substituents selected from the group consisting of hydroxyl and alkyl groups; an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an alkoxy group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. Wherein, two of the aforementioned amino groups may be linked together to form a ring.

[0033] R 12 R 13 and R 14 Each is independently a hydrogen atom; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. The aforementioned amino groups may optionally have two of the aforementioned substituents linked together to form a ring. Wherein, R is absent. 12 R 13 and R 14 (The case where two or more atoms are hydrogen atoms.)

[0034] (3) The terminated polyisocyanate composition according to (1) or (2) above, wherein a portion or all of the terminated polyisocyanate has structural units derived from hydrophilic compounds.

[0035] (4) The capped polyisocyanate composition according to (3) above, wherein the aforementioned structural unit derived from the hydrophilic compound comprises at least one hydrophilic group selected from the group consisting of nonionic hydrophilic groups and anionic hydrophilic groups.

[0036] (5) The capped polyisocyanate composition according to any one of (1) to (4) above, wherein the capping agent comprises one or more of the aforementioned R 11 For alkoxy, the aforementioned R 12 It is hydrogen-based or alkyl and the aforementioned R 13 And the aforementioned R 14 The compound represented by the aforementioned general formula (I) is an alkyl group.

[0037] (6) The capped polyisocyanate composition according to any one of (1) to (5) above, wherein the content of the aforementioned anionic dispersant is 0.01 parts by mass or more and 5 parts by mass or less relative to 100 parts by mass of the aforementioned capped polyisocyanate.

[0038] (7) The capped polyisocyanate composition according to any one of (1) to (6) above, wherein the capped polyisocyanate comprises a capped isocyanurate trimer.

[0039] (8) The capped polyisocyanate composition of any one of (1) to (7) above, wherein the average number of isocyanate functional groups of the aforementioned polyisocyanate is 2.0 or more.

[0040] (9) The capped polyisocyanate composition according to any one of (1) to (8) above, wherein the aforementioned polyisocyanate is a polyisocyanate derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates.

[0041] (10) The capped polyisocyanate composition according to (1) above, wherein the capping agent comprises the compound (B) having a heterocycle containing one or more nitrogen atoms.

[0042] (11) The terminated polyisocyanate composition according to (10) above, wherein the content of the counter cation of the aforementioned carboxylate is 0.1% by mass or more and 20% by mass or less relative to the total mass of the aforementioned terminated polyisocyanate.

[0043] (12) The capped polyisocyanate composition according to (10) or (11) above, wherein the aforementioned carboxylate is a carboxylate metal salt or a carboxylate of a quaternary ammonium cation.

[0044] (13) The capped polyisocyanate composition according to (12) above, wherein the aforementioned carboxylate is a carboxylate metal salt.

[0045] (14) The capped polyisocyanate composition according to (13) above, wherein the metal species of the aforementioned carboxylic acid metal salt is a monovalent metal.

[0046] (15) The capped polyisocyanate composition according to any one of (10) to (14) above, wherein the aforementioned compound having a heterocycle containing one or more nitrogen atoms is a compound having a heterocycle containing two or more nitrogen atoms.

[0047] (16) The terminated polyisocyanate composition according to (15) above, wherein the terminator is a compound having a heterocycle containing three or more nitrogen atoms.

[0048] (17) A resin composition comprising the end-capped polyisocyanate composition and the polyhydroxy compound described in any one of (1) to (16) above.

[0049] (18) The resin composition according to (17) above, wherein the glass transition temperature Tg of the aforementioned polyhydroxy compound is above 0°C and below 100°C.

[0050] (19) The resin composition according to (17) or (18) above, wherein the weight-average molecular weight of the aforementioned polyhydroxy compound is 5.0 × 10⁻⁶. 3Above and 2.0×10 5 the following.

[0051] (20) The resin composition according to any one of (17) to (19) above, wherein the hydroxyl value of the aforementioned polyhydroxy compound is 30 mg KOH / g or more and 250 mg KOH / g or less.

[0052] (21) The resin composition according to any one of (17) to (20) above, wherein the content of the aforementioned end-capped polyisocyanate is 5 parts by mass or more and 200 parts by mass or less relative to 100 parts by mass of the aforementioned polyhydroxy compound.

[0053] (22) A resin film formed by curing the resin composition described in any one of (17) to (21) above.

[0054] (23) The resin film according to (22) above, wherein the resin film with a thickness of 40 μm obtained by heating the aforementioned resin composition at 80°C for 30 minutes is stored at 23°C for 1 week and then immersed in acetone at 23°C for 24 hours has a gelation rate of 80% by mass or more.

[0055] (24) The resin film according to (22) or (23) above, wherein the resin film with a thickness of 40 μm, a width of 10 mm and a length of 40 mm, which is formed by heating the aforementioned resin composition at 80°C for 30 minutes, is set with a distance of 20 mm between the clamps, and the tensile strength in a tensile test performed at a speed of 20 mm / min is 5 MPa or more.

[0056] (25) A laminate comprising two or more resin films of any one of (22) to (24) above, having different compositions.

[0057] The average thickness of each layer of the aforementioned laminate is more than 1 μm and less than 50 μm.

[0058] (26) A hydrophilic polyisocyanate composition, which is a hydrophilic polyisocyanate composition derived from a hydrophilic compound and an alicyclic polyisocyanate having an isocyanurate group.

[0059] The ratio of the isocyanate group modified with the aforementioned hydrophilic compound to the total molar amount of the isocyanate group of the aforementioned alicyclic polyisocyanate is 2 mol% or more and 15 mol% or less.

[0060] (27) The hydrophilic polyisocyanate composition according to (26) above, wherein the aforementioned alicyclic polyisocyanate comprises a polyisocyanate having an isocyanurate group derived from isophorone diisocyanate.

[0061] (28) The hydrophilic polyisocyanate composition according to (26) or (27) above, wherein the average number of isocyanate groups in the aforementioned alicyclic polyisocyanate is 2.5 or more and 6.0 or less.

[0062] (29) The hydrophilic polyisocyanate composition according to any one of (26) to (28) above, wherein the weight average molecular weight of the hydrophilic polyisocyanate composition is 900 or more and 20,000 or less.

[0063] (30) The hydrophilic polyisocyanate composition according to any one of (26) to (29) above, wherein the hydrophilic compound is a nonionic compound or anionic compound.

[0064] (31) A capped polyisocyanate composition, wherein at least a portion of the isocyanate groups in any of the preceding (26) to (30) hydrophilic polyisocyanate compositions are capped by a capping agent.

[0065] (32) The capped polyisocyanate composition according to (31) above, wherein the capping agent is at least one compound selected from the group consisting of active methylene compounds, oxime compounds, amine compounds, pyrazole compounds and triazole compounds.

[0066] (33) A resin composition comprising the hydrophilic polyisocyanate composition described in any one of (26) to (30) above and a polyol.

[0067] (34) A resin composition comprising the end-capped polyisocyanate composition described in (31) or (32) above and a polyol.

[0068] (35) A resin film formed by curing the resin composition described in (33) or (34) above.

[0069] The effects of the invention

[0070] The end-capped polyisocyanate composition according to the above scheme provides an end-capped polyisocyanate composition that exhibits good storage stability when forming a resin composition and good curability at a low temperature of around 80°C when forming a resin film. The resin composition of the above scheme exhibits good storage stability. The resin film of the above scheme exhibits good curability at a low temperature of around 80°C. The laminate of the above scheme comprises two or more layers of the aforementioned resin films with different compositions, and the resin films exhibit good curability at a low temperature of around 80°C.

[0071] The hydrophilic polyisocyanate composition according to the above scheme can provide a hydrophilic polyisocyanate composition with good water dispersibility and excellent hardness when formed into a resin film. The capped polyisocyanate composition formed by sealing the aforementioned hydrophilic polyisocyanate composition with a capping agent has good water dispersibility and excellent hardness when formed into a resin film. The aforementioned polyisocyanate composition or a resin composition containing the aforementioned capped polyisocyanate composition exhibits excellent hardness when formed into a resin film. Detailed Implementation

[0072] The following is a detailed description of this specific embodiment (hereinafter referred to as "the embodiment"). It should be noted that the present invention is not limited to the following embodiments.

[0073] In this specification, "polyol" refers to a compound having two or more hydroxyl groups (-OH).

[0074] In this specification, "polyisocyanate" refers to a reactant formed by the bonding of multiple monomeric compounds having one or more isocyanate groups (-NCO).

[0075] <<Capped Polyisocyanate Compositions>>

[0076] The capped polyisocyanate composition of the first embodiment of the present invention comprises a capped polyisocyanate derived from a polyisocyanate and one or more capping agents, and an anionic dispersant.

[0077] The capping agent comprises (A) a compound represented by the following general formula (I) (hereinafter sometimes referred to as "compound (I)") or (B) a compound having a heterocycle containing one or more nitrogen atoms.

[0078]

[0079] (In the aforementioned general formula (I),

[0080] R 11 The amino group is a hydroxyl group; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; an amino group optionally containing one or more substituents selected from the group consisting of hydroxyl and alkyl groups; an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an alkoxy group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. Wherein, two of the aforementioned amino groups may be linked together to form a ring.

[0081] R 12 R 13 and R 14Each is independently a hydrogen atom; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. The aforementioned amino groups may optionally have two of the aforementioned substituents linked together to form a ring. Wherein, R is absent. 12 R 13 and R 14 (The case where two or more atoms are hydrogen atoms.)

[0082] Furthermore, for anionic dispersants, the surface tension of an aqueous solution containing water and 0.1% by mass of the aforementioned anionic dispersant relative to the total mass of the aqueous solution, as determined by the Wilhelmy method, at 25°C is 32 mN / m or more and 51 mN / m or less, preferably 34 mN / m or more and 50 mN / m or less, more preferably 36 mN / m or more and 48 mN / m or less, and even more preferably 37 mN / m or more and 47 mN / m or less. By keeping the surface tension within the above range, the storage stability when preparing the resin composition can be well maintained.

[0083] Previously, capped polyisocyanate compositions using malonates with secondary or tertiary alkyl groups (such as diisopropyl malonate and di-tert-butyl malonate) as capping agents exhibited excellent curing properties at low temperatures of around 80°C. However, they showed high reactivity with the hydroxyl groups of polyols and other polyhydroxy compounds to be reacted, leading to a significant increase in viscosity and gelation when stored as resin compositions containing both the main agent and the curing agent. In particular, the aforementioned problem was significantly observed in mixtures obtained by combining capped polyisocyanate compositions using tertiary alkyl malonates (such as di-tert-butyl malonate) as capping agents with aqueous polyols, and improvements were desired.

[0084] In contrast, the capped polyisocyanate composition of this embodiment improves the above-mentioned problems by including an anionic dispersant with a surface tension in the above range, and can effectively suppress the viscosity increase and gelation of the mixture of capped polyisocyanate composition and polyhydroxy compound during storage, thus exhibiting good storage stability.

[0085] As a method for measuring the aforementioned surface tension, the following method can be used. First, the anionic dispersant is diluted with water to prepare an aqueous solution containing water and 0.1% by mass of the aforementioned anionic dispersant relative to the total mass of the aqueous solution. Next, using this aqueous solution, the surface tension at 25°C is measured using the Wilhelmy method (also known as the plate method or vertical plate method). Specifically, the plate, acting as the measuring element, is brought into contact with the surface of the aqueous solution, thereby wetting the plate. At this point, surface tension acts along the perimeter of the plate, and a force is applied to pull the plate into the aqueous solution. This pulling force F (the force acting on the plate, the measuring force) can be read, and the surface tension r is measured using the following formula. It should be noted that in the formula, L is the perimeter of the plate (m), and θ is the contact angle between the plate and the aqueous solution.

[0086] r = F / (L×cosθ)

[0087] The surface tension mentioned above can also be measured using commercially available measuring devices, such as static surface tension measuring systems (manufactured by DKSH JAPAN, models: TD1C or TD3).

[0088] Hereinafter, each component contained in the capped polyisocyanate composition of this embodiment will be described in detail.

[0089] <Terminated polyisocyanates>

[0090] End-capped polyisocyanates are products of the reaction between polyisocyanates and end-capping agents. That is, at least one of the isocyanate groups in the end-capped polyisocyanate is end-capped using an end-capping agent.

[0091] The capped polyisocyanate may have one or more functional groups selected from the group consisting of urea carbamate group, urea diketone group, iminooxadiazine diketone group, isocyanurate group, carbamate group, and biuret group. Among them, from the perspective of excellent weather resistance, the inclusion of isocyanurate group is preferred.

[0092] The capped polyisocyanate preferably comprises a capped isocyanurate trimer. The term "isocyanurate trimer" as used herein refers to a polyisocyanate having isocyanurate groups derived from three isocyanate monomer molecules. Furthermore, "capped isocyanurate trimer" refers to a trimer in which at least a portion (preferably all) of the isocyanurate groups have been capped using a capping agent. By including the capped isocyanurate trimer, there is a tendency for the resin film to exhibit superior heat resistance.

[0093] [Polyisocyanates]

[0094] Polyisocyanates used to manufacture end-capped polyisocyanates are reactants obtained by reacting multiple monomeric compounds (hereinafter sometimes referred to as "isocyanate monomers") having one or more isocyanate groups (-NCO).

[0095] The isocyanate monomer is preferably an isocyanate monomer with 4 or more and 30 or fewer carbon atoms. Specifically, examples of isocyanate monomers include the following. These isocyanate monomers can be used alone or in combination of two or more.

[0096] (1) Aromatic diisocyanates such as diphenylmethane-4,4'-diisocyanate (MDI), 1,5-naphthalene diisocyanate, toluene diisocyanate (TDI), phenyl dimethyl diisocyanate, and m-tetramethylphenyl dimethyl diisocyanate (TMXDI).

[0097] (2) Aliphatic diisocyanates such as 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (hereinafter sometimes referred to as "HDI"), 2,2,4-trimethyl-1,6-diisocyanohexane, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, 2-methylpentane-1,5-diisocyanate (MPDI), and lysine diisocyanate (hereinafter sometimes referred to as "LDI").

[0098] (3) Isophorone diisocyanate (hereinafter sometimes referred to as "IPDI"), 1,3-bis(diisocyanate methyl)cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, norbornane diisocyanate, and other alicyclic diisocyanates.

[0099] (4) Triisocyanates such as 4-isocyanate methyl-1,8-octamethylene diisocyanate (hereinafter sometimes referred to as "NTI"), 1,3,6-hexamethylene triisocyanate (hereinafter sometimes referred to as "HTI"), bis(2-isocyanoethyl)2-isocyanoglutarate (hereinafter sometimes referred to as "GTI"), and lysine triisocyanate (hereinafter sometimes referred to as "LTI").

[0100] From the perspective of excellent weather resistance, the isocyanate monomer is preferably one or more diisocyanates selected from the group consisting of aliphatic and alicyclic diisocyanates. Furthermore, from the perspective of ease of industrial availability, HDI or IPDI is more preferred as the isocyanate monomer. Moreover, from the viewpoint of achieving low viscosity of the end-capped polyisocyanate component, HDI is further preferred as the isocyanate monomer.

[0101] (Manufacturing method of polyisocyanates)

[0102] The manufacturing method of polyisocyanates is described in detail below.

[0103] Polyisocyanates can be obtained, for example, by simultaneously carrying out ureocarboxylation reactions to form ureacarboxyl groups, ureadone reactions to form ureadiketone groups, iminooxadiazinediketone reactions to form iminooxadiazinediketone groups, isocyanurate reactions to form isocyanurate groups, urethane reactions to form urethane groups, and biuret reactions to form biuret groups in the presence of excess isocyanate monomers, and removing unreacted isocyanate monomers after the reactions are completed. That is, the polyisocyanate obtained by the above reactions is composed of multiple of the above-mentioned isocyanate monomers bonded together, and has one or more reactants selected from the group consisting of ureacarboxyl groups, ureadiketone groups, iminooxadiazinediketone groups, isocyanurate groups, urethane groups, and biuret groups.

[0104] In addition, the above reactions can be carried out separately, and the resulting polyisocyanates can be mixed in a specified ratio.

[0105] From the viewpoint of ease of manufacture, it is preferable to carry out the above reactions simultaneously to obtain polyisocyanates. From the viewpoint of freely adjusting the molar ratio of each functional group, it is preferable to manufacture them separately and then mix them.

[0106] For example, commonly used isocyanurate esterification catalysts can be listed as catalysts for deriving polyisocyanates containing isocyanurate groups from isocyanate monomers.

[0107] There are no particular limitations on the catalyst used for the isocyanurate esterification reaction, but it is generally preferred to be basic. Specifically, catalysts such as those shown below can be listed as catalysts for the isocyanurate esterification reaction.

[0108] 1) Hydroxides of tetraalkylammonium such as tetramethylammonium, tetraethylammonium, and tetrabutylammonium; and organic weak acid salts such as acetate, propionate, octanoate, decanoate, myristate, and benzoate of the aforementioned tetraalkylammonium.

[0109] 2) Hydroxides of aryltrialkylammonium such as benzyltrimethylammonium and trimethylphenylammonium; and organic weak acid salts such as acetate, propionate, octanoate, decanoate, myristate, and benzoate of the aforementioned aryltrialkylammonium.

[0110] 3) Hydroxides of hydroxyalkylammonium such as trimethylhydroxyethylammonium, trimethylhydroxypropylammonium, triethylhydroxyethylammonium, and triethylhydroxypropylammonium; and organic weak acid salts such as acetates, propions, octanoates, decanoates, myristates, and benzoates of the aforementioned hydroxyalkylammonium.

[0111] 4) Metal salts of alkyl carboxylic acids such as acetic acid, propionic acid, hexanoic acid, octanoic acid, decanoic acid, and myristic acid, such as tin, zinc, and lead.

[0112] 5) Alkoxides of metals such as sodium and potassium.

[0113] 6) Compounds containing aminosilyl groups, such as hexamethylenedisilazane.

[0114] 7) Mannich bases.

[0115] 8) Mixtures of tertiary amines and epoxides.

[0116] 9) Phosphorus compounds such as tributylphosphine.

[0117] From the viewpoint of minimizing the generation of unwanted byproducts, the preferred catalyst for the isocyanurate esterification reaction is a quaternary ammonium hydroxide or an organic weak acid salt of quaternary ammonium, more preferably a tetraalkylammonium hydroxide, an organic weak acid salt of tetraalkylammonium, an aryltrialkylammonium hydroxide, or an organic weak acid salt of aryltrialkylammonium.

[0118] The upper limit of the amount of the catalyst used in the above-mentioned isocyanurate esterification reaction is preferably 1000 ppm by mass relative to the mass of the added isocyanate monomer, more preferably 500 ppm by mass, and even more preferably 100 ppm by mass.

[0119] On the other hand, there is no particular limit to the lower limit of the amount of the catalyst used in the above-mentioned isocyanurate esterification reaction, which can be, for example, 10 ppm by mass.

[0120] The preferred temperature for the isocyanurate esterification reaction is 50°C or higher and 120°C or lower, more preferably 55°C or higher and 90°C or lower. By setting the isocyanurate esterification reaction temperature to the above-mentioned upper limit or lower, there is a tendency to more effectively suppress the coloring of polyisocyanates, etc.

[0121] At the point when the desired conversion rate (the ratio of the mass of the polyisocyanate generated in the isocyanurate esterification reaction to the mass of the isocyanate monomer input) is reached, the isocyanurate esterification reaction is stopped by adding an acidic compound (such as phosphoric acid, acid phosphate, etc.).

[0122] It should be noted that to obtain polyisocyanates, the reaction needs to be stopped at the initial stage. However, the isocyanurate esterification reaction is very rapid in the initial stage, making it difficult to stop the reaction at this stage. Careful selection of reaction conditions, especially the amount and method of catalyst addition, is necessary. For example, adding the catalyst in stages at regular intervals is recommended as a suitable method.

[0123] Therefore, the conversion rate of the isocyanurate esterification reaction used to obtain polyisocyanates is preferably 10% or more and 60% or less, more preferably 15% or more and 55% or less, and even more preferably 20% or more and 50% or less.

[0124] By keeping the conversion rate of the isocyanurate esterification reaction below the upper limit mentioned above, the viscosity of the capped polyisocyanate component can be lowered. Furthermore, by keeping the conversion rate of the isocyanurate esterification reaction above the lower limit mentioned above, the reaction cessation operation can be performed more easily.

[0125] In addition, when deriving polyisocyanates containing isocyanurate groups, alcohols with a 1- or higher octet and a 6- or lower octet can be used, in addition to the isocyanate monomers mentioned above.

[0126] Examples of usable alcohols with a 1- or higher but less than 6-membered group include, for example, non-polymerizable alcohols and polymerizable alcohols. Here, "non-polymerizable alcohols" refers to alcohols that do not possess polymerizable groups. On the other hand, "polymerizable alcohols" refer to alcohols obtained by polymerizing monomers that possess polymerizable groups and hydroxyl groups.

[0127] As non-polymerizable alcohols, examples include monools, diols, triols, tetraols, and other polyols.

[0128] Examples of monools include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, n-pentanol, n-hexanol, n-octanol, n-nonanol, 2-ethylbutanol, 2,2-dimethylhexanol, 2-ethylhexanol, cyclohexanol, methylcyclohexanol, and ethylcyclohexanol.

[0129] 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.

[0130] Examples of triols include glycerol and trimethylolpropane.

[0131] Examples of tetraols include pentaerythritol.

[0132] As a polymerizable alcohol, there are no particular limitations; examples include polyester polyols, polyether polyols, acrylic polyols, and polyolefin polyols.

[0133] As a type of polyester polyol, there are no particular limitations, and examples include products obtained by condensation reactions of dicarboxylic acids alone or in mixtures with polyols alone or in mixtures.

[0134] As a dicarboxylic acid, there are no particular limitations, but at least one dicarboxylic acid can be listed, for example, from the group consisting of carboxylic acids such as succinic acid, adipic acid, sebacic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, and terephthalic acid.

[0135] As a polyol, there is no particular limitation, and examples include at least one polyol selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, neopentyl glycol, trimethylolpropane and glycerol.

[0136] In addition, examples of polyester polyols include polycaprolactones obtained by ring-opening polymerization of ε-caprolactone using the aforementioned polyols.

[0137] As for polyether polyols, there are no particular limitations. Examples include polyether polyols obtained by adding one or a mixture of epoxides to polyols using alkali metal hydroxides or strong alkaline catalysts; polyether polyols obtained by reacting epoxides with polyamine compounds; and so-called polymer polyols obtained by polymerizing acrylamide and the like using the above-mentioned polyethers as a medium.

[0138] Examples of alkali metals include lithium, sodium, and potassium.

[0139] Examples of strong basic catalysts include alkoxides and alkylamines.

[0140] As polyols, examples of polyols that are the same as those exemplified in the above-mentioned polyester polyols can be listed.

[0141] Examples of epoxides include ethylene oxide, propylene oxide, butane oxide, cyclohexane oxide, and phenylene oxide.

[0142] Examples of polyamine compounds include ethylenediamines.

[0143] As an acrylic polyol, there are no particular limitations, and examples include substances obtained by copolymerizing one or a mixture of monomers containing olefinic unsaturated bonds with hydroxyl groups with one or a mixture of other monomers containing olefinic unsaturated bonds that can be copolymerized with them.

[0144] As monomers containing hydroxyl groups and olefinic unsaturated bonds, there are no particular limitations, and examples include hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate.

[0145] Other monomers containing olefinic unsaturated bonds that can copolymerize with monomers containing olefinic unsaturated bonds having hydroxyl groups are not particularly limited, and examples include acrylates, methacrylates, unsaturated carboxylic acids, unsaturated amides, vinyl monomers, and vinyl monomers having hydrolyzable silyl groups.

[0146] Examples of acrylates include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, benzyl acrylate, and phenyl acrylate.

[0147] Examples of methacrylates include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, benzyl methacrylate, and phenyl methacrylate.

[0148] Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, and itaconic acid.

[0149] Examples of unsaturated amides include acrylamide, methacrylamide, N,N-methylenebisacrylamide, diacetone acrylamide, diacetone methacrylamide, maleic acid amide, and maleimide.

[0150] Examples of vinyl monomers include glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, and dibutyl fumarate.

[0151] Examples of vinyl monomers with hydrolyzable silyl groups include vinyltrimethoxysilane, vinylmethyldimethoxysilane, and γ-(meth)acryloyloxypropyltrimethoxysilane.

[0152] Examples of polyolefin polyols include terminally hydroxylated polybutadiene and its hydrogenated derivatives.

[0153] Urethyl carbamate, ureidyl diketation, iminooxadiazine diketation, isocyanurate, carbamate, and biuretization can be carried out sequentially or several of them can be carried out simultaneously.

[0154] Polyisocyanates can be obtained by removing unreacted isocyanate monomers from the reaction solution after the reaction is completed through methods such as thin-film distillation and extraction.

[0155] In addition, antioxidants and ultraviolet absorbers may be added to inhibit, for example, discoloration of the obtained polyisocyanates during storage.

[0156] Examples of antioxidants include hindered phenols such as 2,6-di-tert-butyl-p-cresol. Examples of UV absorbers include benzotriazole and benzophenone. These antioxidants and UV absorbers can be used alone or in combination of two or more. The preferred amount of these additives relative to the mass of the polyisocyanate is 10 ppm by mass or more and 500 ppm by mass or less.

[0157] (Average number of isocyanate functional groups in polyisocyanates)

[0158] From the viewpoint of improving the low-temperature curability when forming a resin film, the average number of isocyanate functional groups of the polyisocyanate is preferably 2.0 or more. From the viewpoint of balancing the low-temperature curability when forming a resin film and the compatibility with polyol compounds, it is more preferably 3.0 or more, further preferably 4.6 or more and 20 or less, and particularly preferably 5 or more and 10 or less.

[0159] The average number of isocyanate functional groups in polyisocyanates can be determined using the methods described in the examples below.

[0160] [End-capping agent]

[0161] The capping agent used to manufacture the capped polyisocyanate comprises (A) a compound represented by the following general formula (I) (compound (I)). The capping agent may comprise one compound (I) alone or in combination of two or more compounds.

[0162]

[0163] (Compound (I))

[0164] (1)R 11

[0165] In general formula (I), R 11 The amino group is a hydroxyl group; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; an amino group optionally containing one or more substituents selected from the group consisting of hydroxyl and alkyl groups; an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an alkoxy group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. Wherein, two of the aforementioned amino groups may be linked together to form a ring.

[0166] R 11When the alkyl group is an unsubstituent alkyl group, the number of carbon atoms is preferably 1 or more and 30 or less, more preferably 1 or more and 8 or less, further preferably 1 or more and 6 or less, and particularly preferably 1 or more and 4 or less. Examples of unsubstituent alkyl groups include, specifically, methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, sec-butyl, isobutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylbutyl, n-hexyl, 2-methylpentyl, 3-methylpentyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, n-heptyl, 2-methylhexyl, 3-methylhexyl, 2,2-dimethylpentyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, 3,3-dimethylpentyl, 3-ethylpentyl, 2,2,3-trimethylbutyl, n-octyl, isooctyl, 2-ethylhexyl, nonyl, decyl, etc.

[0167] In addition, R 11 When the alkyl group has a substituent, the substituent is a hydroxyl or amino group.

[0168] Alkyl groups containing hydroxyl groups as substituents include, for example, hydroxymethyl, hydroxyethyl, and hydroxypropyl.

[0169] Alkyl groups containing an amino group as a substituent include, for example, aminomethyl, aminoethyl, aminopropyl, and aminobutyl.

[0170] Alkyl groups containing hydroxyl and amino groups as substituents include, for example, hydroxyaminomethyl, hydroxyaminoethyl, hydroxyaminopropyl, etc.

[0171] R 11 When the amino group has a substituent, the substituent is a hydroxyl or alkyl group.

[0172] Amino groups with hydroxyl groups as substituents include hydroxyl amino groups (-NH-OH).

[0173] Amino groups with alkyl substituents include, for example, methylamino, ethylamino, n-butylamino, dimethylamino, diethylamino, dipropylamino, diisopropylamino, di-n-butylamino, di-tert-butylamino, di-sec-butylamino, diisobutylamino, 2,6-dimethylpiperidinyl, etc.

[0174] Amino groups with hydroxyl and alkyl substituents include, for example, hydroxymethylene amino, hydroxyethylamino, hydroxypropylamino, and hydroxybutylamino.

[0175] Examples of cyclic secondary amino groups that form a ring by linking two substituents include ethyleneimino, aziridine, pyrrolyl, piperidinyl, 2,6-dimethylpiperidinyl, and hexamethyleneimino.

[0176] R 11When the aryl group is unsubstituent, the number of carbon atoms is preferably 5 or more and 30 or less, more preferably 6 or more and 20 or less, and even more preferably 6 or more and 14 or less. Specifically, examples of the aforementioned aryl group include monocyclic aromatic hydrocarbon groups, dicyclic aromatic hydrocarbon groups, tricyclic aromatic hydrocarbon groups, tetracyclic aromatic hydrocarbon groups, pentacyclic aromatic hydrocarbon groups, hexacyclic aromatic hydrocarbon groups, and heptacyclic aromatic hydrocarbon groups.

[0177] Examples of monocyclic aromatic hydrocarbon groups include phenyl, benzyl, tolyl, and o-xylyl.

[0178] Examples of bicyclic aromatic hydrocarbon groups include indanyl, indanyl, pentanyl, chamomileyl, naphthyl, and tetrahydronaphthyl.

[0179] Examples of tricyclic aromatic hydrocarbon groups include anthracene, fluorenyl, phenatenyl, and phenanthrene.

[0180] Examples of tetracyclic aromatic hydrocarbon groups include pyrene, benzotetraphenyl, etc. Base, etc.

[0181] Examples of pentacyclic aromatic hydrocarbon groups include peryl, styrene, and pentyl.

[0182] Examples of hexacyclic aromatic hydrocarbon groups include naphthyl pyrene.

[0183] Examples of heptaneous aromatic hydrocarbon groups include the keratinyl group.

[0184] R 11 When the aryl group has substituents, the substituents are hydroxyl or amino.

[0185] Aryl groups containing a hydroxyl group as a substituent include, for example, phenolic groups.

[0186] Aryl groups containing amino groups as substituents include, for example, aniline groups.

[0187] Aryl groups containing hydroxyl and amino groups as substituents include, for example, aminophenol (hydroxyaniline).

[0188] R 11When the alkoxy group is an unsubstituent alkoxy group, the number of carbon atoms is preferably 1 or more and 30 or less, more preferably 1 or more and 8 or less, further preferably 1 or more and 6 or less, and particularly preferably 1 or more and 4 or less. Specifically, examples of the aforementioned alkoxy groups include methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, sec-butoxy, isobutoxy, n-pentoxy, isopentoxy, neopentoxy, tert-pentoxy, 1-methylbutoxy, n-hexyloxy, 2-methylpentoxy, 3-methylpentoxy, 2,2-dimethylbutoxy, 2,3-dimethylbutoxy, n-heptoxy, 2-methylhexyloxy, 3-methylhexyloxy, 2,2-dimethylpentoxy, 2,3-dimethylpentoxy, 2,4-dimethylpentoxy, 3,3-dimethylpentoxy, 3-ethylpentoxy, 2,2,3-trimethylbutoxy, n-octoxy, isooctoxy, 2-ethylhexyloxy, nonoxy, and decoxy.

[0189] R 11 When the alkoxy group has a substituent, the substituent is a hydroxyl or amino group.

[0190] Alkoxy groups containing hydroxyl groups as substituents include, for example, hydroxymethyleneoxy, hydroxyethyloxy, hydroxypropyloxy, and hydroxybutyloxy.

[0191] Alkoxy groups containing an amino group as a substituent include, for example, aminomethyleneoxy, aminoethyloxy, aminopropyleneoxy, and aminobutyloxy.

[0192] Alkoxy groups containing hydroxyl and amino groups as substituents include, for example, hydroxyaminomethyleneoxy, hydroxyaminoethyloxy, hydroxyaminopropyloxy, etc.

[0193] Among them, as R 11 Preferably, it is an alkoxy group with or without substituents, and more preferably an alkoxy group without substituents.

[0194] (2)R 12 R 13 and R 14

[0195] In general formula (I), R 12 R 13 and R 14 Each is independently a hydrogen atom; an alkyl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups; or an aryl group optionally containing one or more substituents selected from the group consisting of hydroxyl and amino groups. The aforementioned amino groups may optionally have two of the aforementioned substituents linked together to form a ring. Wherein, R is absent. 12 R 13 and R 14 The case where there are two or more hydrogen atoms.

[0196] As the aforementioned alkyl and aryl groups, examples of those related to the aforementioned "R" can be listed. 11 The same group as the group shown in the example.

[0197] Examples of cyclic secondary amino groups that form a ring by linking the two substituents mentioned above include ethyleneimine, aziridine, pyrrolidinyl, and piperidinyl.

[0198] Among them, R is preferred. 12 It is a hydrogen atom or an alkyl group with or without substituents, and R 13 and R 14 Each is independently an alkyl group with or without substituents, more preferably R. 12 It is a hydrogen atom or an alkyl group without substituents, and R 13 and R 14 Each is an alkyl group that does not have substituents.

[0199] Of the compounds (I), R is preferred due to its ease of industrial availability and excellent curability at low temperatures. 11 For alkoxy, R 12 It is a hydrogen atom or an alkyl group, and R 13 and R 14 It is an alkyl group. The capping agent may contain one of the compounds (I) described above, or it may contain two or more compounds in combination.

[0200] Furthermore, by giving compound (I) a tert-butyl ester structure or a tert-amyl ester structure, it exhibits excellent low-temperature curing properties when forming a resin film. In addition, by giving compound (I) a sec-butyl ester structure or an isopropyl ester structure, it tends to exhibit excellent storage stability when forming a resin composition.

[0201] Preferred compounds (I) include, specifically, di-tert-butyl malonate, di-tert-pentyl malonate, di-sec-butyl malonate, diisopropyl malonate, ethyl tert-butyl malonate, and ethyl isopropyl malonate.

[0202] From the viewpoint of low-temperature curing properties when forming a resin film, di-tert-butyl malonate, di-tert-pentyl malonate, di-sec-butyl malonate, or diisopropyl malonate are preferred, and from the viewpoint of water dispersion stability, di-tert-butyl malonate or diisopropyl malonate are more preferred.

[0203] As a capping agent for the manufacture of capped polyisocyanates, (B) compounds having a heterocycle containing one or more nitrogen atoms can also be used.

[0204] From the viewpoint of low-temperature curability, the aforementioned (B) compound having a heterocycle containing one or more nitrogen atoms is preferably a compound having a heterocycle containing two or more nitrogen atoms, and more preferably a compound having a heterocycle containing three or more nitrogen atoms.

[0205] Examples of compounds having a heterocycle containing one or more nitrogen atoms include the compounds shown below.

[0206] 1) Aziridine-based end-capping agents such as ethyleneimine;

[0207] 2) Acetidine-based end-capping agents such as azacyclobutane;

[0208] 3) Pyrrolidine and other azacyclopentane end-capping agents;

[0209] 4) Pyrrole, 2H-pyrrole, and other azole-based end-capping agents;

[0210] 5) Imidazoline-based end-capping agents such as 2-methylimidazoline and 2-phenylimidazoline;

[0211] 6) Pyrimidine-based end-capping agents such as 2-methyl-1,4,5,6-tetrahydropyrimidine;

[0212] 7) Pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole, imidazole, 2-methylimidazolium, 4-methylimidazolium, 2-ethylimidazolium, 2-isopropylimidazolium, 2,4-dimethylimidazolium, 2-ethyl-4-methylimidazolium, 2-phenylimidazolium, 4-methyl-2-phenylimidazolium, benzimidazole, 2-methylbenzimidazole and other diazole-based end-capping agents;

[0213] 8) Triazole-based end-capping agents such as 1,2,4-triazole, 1,2,3-triazole, and 3,5-dimethyl-1,2,4-triazole;

[0214] 9) Tetraazole-based end-capping agents such as 1H-1,2,3,4-tetraazole.

[0215] Among these, 1,2,4-triazole, 1,2,3-triazole, etc. are preferred triazole-based end-capping agents.

[0216] (Other capping agents)

[0217] In addition to compounds (I) or (B) having a heterocyclic ring containing one or more nitrogen atoms, the capping agent used to manufacture capped polyisocyanates may further include other capping agents to the extent that it does not impair the storage stability when the resin composition is made and the low-temperature curability when the resin film is made.

[0218] It should be noted that, relative to the total molar amount of all capping agents used to manufacture the capped polyisocyanate, the content of the compound (I) or (B) having a heterocycle containing one or more nitrogen atoms is preferably 5 mol% or more, more preferably 50 mol% or more, further preferably 70 mol% or more, even more preferably 80 mol% or more, particularly preferably 90 mol% or more, and most preferably 100 mol%.

[0219] By ensuring that the content of compounds (I) or (B) containing a heterocycle with one or more nitrogen atoms is within the above-mentioned range, the low-temperature curability of the resin film can be further improved.

[0220] Other end-capping agents include, for example, 1) alcohol compounds, 2) alkylphenol compounds, 3) phenol compounds, 4) active methylene compounds other than compound (I), 5) thiol compounds, 6) acid amide compounds, 7) acid imide compounds, 8) imidazole compounds, 9) urea compounds, 10) oxime compounds, 11) amine compounds, 12) imide compounds, 13) bisulfites, 14) pyrazole compounds, and 15) triazole compounds. More specifically, end-capping agents are those shown below.

[0221] 1) Alcohols: methanol, ethanol, 2-propanol, n-butanol, sec-butanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, etc.

[0222] 2) Alkylphenol compounds: Monoalkylphenols and dialkylphenols having alkyl groups with 4 or more carbon atoms as substituents. Specifically, examples of alkylphenol compounds include 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.

[0223] 3) Phenolic compounds: phenol, cresol, ethylphenol, styrylated phenol, hydroxybenzoate, etc.

[0224] 4) Active methylene compounds: dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, etc.

[0225] 5) Thiol compounds: butyl mercaptan, dodecyl mercaptan, etc.

[0226] 6) Acid amide compounds: acetanilide, acetamide, ε-caprolactam, δ-valerolactam, γ-butyrolactam, etc.

[0227] 7) Acid imide compounds: succinimide, maleimide, etc.

[0228] 8) Imidazole compounds: imidazole, 2-methylimidazole, etc.

[0229] 9) Urea compounds: urea, thiourea, ethylene urea, etc.

[0230] 10) Oxime compounds: formaldehyde oxime, acetaldehyde oxime, acetone oxime, methyl ethyl ketone oxime, cyclohexanone oxime, etc.

[0231] 11) Amine compounds: diphenylamine, aniline, carbazole, di-n-propylamine, diisopropylamine, isopropyl ethylamine, etc.

[0232] 12) Imine compounds: ethyleneimine, polyethyleneimine, etc.

[0233] 13) Bisulfite compounds: sodium bisulfite, etc.

[0234] 14) Pyrazole compounds: pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole, etc.

[0235] 15) Triazole compounds: 3,5-dimethyl-1,2,4-triazole, etc.

[0236] [Hydrophilic compounds]

[0237] The terminated polyisocyanate composition of this embodiment may contain terminated polyisocyanates that have structural units derived from hydrophilic compounds in part or all of them.

[0238] That is, some or all of the end-capped polyisocyanates contained in the end-capped polyisocyanate composition of this embodiment may be hydrophilic end-capped polyisocyanates.

[0239] In order to react with one isocyanate group, the hydrophilic compound preferably has one or more active hydrogen groups relative to one molecule of the hydrophilic compound, which are used to react with the isocyanate group of the polyisocyanate. Specifically, active hydrogen groups can be listed as hydroxyl, mercapto, carboxylic acid, amino, and thiol groups.

[0240] Examples of hydrophilic groups include nonionic hydrophilic groups, cationic hydrophilic groups, and anionic hydrophilic groups. These hydrophilic groups can be used individually or in combination of two or more. From the viewpoint of ease of acquisition and minimal electrical interaction with the compound, nonionic hydrophilic groups are preferred as hydrophilic groups, while anionic hydrophilic groups are preferred from the viewpoint of suppressing a decrease in the hardness of the resulting resin film.

[0241] (Hydrophilic compounds with nonionic hydrophilic groups)

[0242] Hydrophilic compounds possessing nonionic hydrophilic groups include, specifically, monools and compounds obtained by adding ethylene oxide to the hydroxyl groups of alcohols. Examples of monools include methanol, ethanol, and butanol. Examples of compounds obtained by adding ethylene oxide to the hydroxyl groups of alcohols include ethylene glycol, diethylene glycol, polyethylene glycol, and polyethylene glycol monomethyl ether. These hydrophilic compounds possessing nonionic hydrophilic groups also have active hydrogen groups that react with isocyanate groups.

[0243] The number of ethylene oxide additions in the compound containing ethylene oxide is preferably 4 or more and 30 or less, more preferably 4 or more and 20 or less. By setting the number of ethylene oxide additions to the lower limit or above, there is a tendency to more effectively impart water dispersibility to the end-capped polyisocyanate composition; by setting the number of ethylene oxide additions to the upper limit or below, there is a tendency to be less prone to the formation of precipitates from the end-capped polyisocyanate composition during low-temperature storage.

[0244] Among them, monools are preferred as hydrophilic compounds having nonionic hydrophilic groups, from the perspective of being able to improve the water dispersibility of the end-capped polyisocyanate composition with a smaller amount.

[0245] From the viewpoint of the water dispersion stability of the capped polyisocyanate composition, the lower limit of the amount of nonionic hydrophilic groups added to the capped polyisocyanate (hereinafter sometimes referred to as "content of nonionic hydrophilic groups") is preferably 1% by mass, more preferably 2% by mass, further preferably 3% by mass, and particularly preferably 4% by mass relative to the mass of the solid component of the capped polyisocyanate composition.

[0246] Furthermore, from the viewpoint of the water resistance of the resulting resin film, the upper limit of the content of nonionic hydrophilic groups is preferably 30% by mass, more preferably 20% by mass, further preferably 18% by mass, and particularly preferably 15% by mass relative to the solid content of the capped polyisocyanate composition.

[0247] That is, the content of nonionic hydrophilic groups relative to the mass of the nonvolatile components of the capped polyisocyanate composition is preferably 1% or more and 30% or less by mass, more preferably 2% or more and 20% or less by mass, further preferably 3% or more and 18% or less by mass, and particularly preferably 4% or more and 15% or less by mass.

[0248] By keeping the content of nonionic hydrophilic groups within the above range, there is a tendency for the capped polyisocyanate composition to be further dispersed in water, resulting in improved water resistance of the resin film.

[0249] (Hydrophilic compounds with cationic hydrophilic groups)

[0250] Specifically, compounds possessing both cationic hydrophilic groups and active hydrogen groups can be listed as hydrophilic compounds. Furthermore, compounds possessing active hydrogen groups such as glycidyl groups can be combined with compounds possessing cationic hydrophilic groups such as sulfides and phosphine to form hydrophilic compounds. In this case, the compound possessing an isocyanate group is first reacted with the compound possessing an active hydrogen group to add a functional group such as a glycidyl group, and then the sulfide, phosphine, etc., are reacted. From the viewpoint of ease of manufacture, compounds possessing both cationic hydrophilic groups and active hydrogen groups are preferred.

[0251] Compounds possessing both cationic hydrophilic groups and active hydrogen groups include, specifically, dimethylethanolamine, diethylethanolamine, diethanolamine, and methyldiethanolamine. Furthermore, tertiary amino groups formed by addition reactions using these compounds can also be quaternized using, for example, dimethyl sulfate or diethyl sulfate.

[0252] The reaction of hydrophilic compounds with cationic hydrophilic groups with polyisocyanates can occur in the presence of a solvent. The solvent is preferably free of active hydrogen groups; specific examples include ethyl acetate, propylene glycol monomethyl ether acetate, and dipropylene glycol dimethyl ether.

[0253] The cationic hydrophilic group added to the capped polyisocyanate is preferably neutralized using a compound having an anionic group. Specifically, examples of such anionic groups include carboxyl groups, sulfonic acid groups, phosphate groups, halogen groups, and sulfate groups.

[0254] Compounds containing a carboxyl group include, specifically, formic acid, acetic acid, propionic acid, butyric acid, and lactic acid.

[0255] Compounds containing sulfonic acid groups include, for example, ethanesulfonic acid.

[0256] Compounds containing a phosphate group include, specifically, phosphoric acid and acid phosphate esters.

[0257] Compounds containing halogen groups include, for example, hydrochloric acid.

[0258] Compounds containing a sulfuric acid group include, specifically, sulfuric acid.

[0259] Among them, the compound having an anionic group is preferably a compound having a carboxyl group, and more preferably acetic acid, propionic acid or butyric acid.

[0260] (Hydrophilic compounds with anionic hydrophilic groups)

[0261] As anionic hydrophilic groups, specifically, carboxyl groups, sulfonic acid groups, phosphate groups, halogen groups, and sulfate groups can be listed.

[0262] As a hydrophilic compound having anionic hydrophilic groups, specifically, compounds that simultaneously have anionic groups and active hydrogen groups can be listed, and more specifically, compounds that have carboxyl groups of monohydroxycarboxylic acids or polyhydroxycarboxylic acids as anionic groups can be listed.

[0263] Examples of monohydroxycarboxylic acids include 1-hydroxyacetic acid, 3-hydroxypropionic acid, 12-hydroxy-9-octadecanoic acid, hydroxypentanoic acid (hydroxypentanoic acid), and lactic acid.

[0264] Examples of compounds that have a carboxyl group of polyhydroxycarboxylic acid as an anionic group include dihydroxymethylacetic acid, 2,2-dihydroxymethylbutyric acid, 2,2-dihydroxymethylvalerate, dihydroxysuccinic acid, and dihydroxymethylpropionic acid.

[0265] In addition, compounds that have both sulfonic acid groups and active hydrogen groups can be listed, and more specifically, hydroxyethanesulfonic acid can be listed as an example.

[0266] Among them, hydroxypentanoic acid or dimethylolpropionic acid are preferred as compounds that simultaneously possess anionic groups and active hydrogen groups.

[0267] The anionic hydrophilic group added to the capped polyisocyanate is preferably neutralized using an amine compound, which is a basic substance.

[0268] As amine compounds, examples include ammonia and water-soluble amino compounds.

[0269] Specifically, 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. Tertiary amines such as triethylamine and dimethylethanolamine can also be used. These amine compounds can be used alone or in combination of two or more.

[0270] <Anionic Dispersants>

[0271] The capped polyisocyanate composition of this embodiment contains an anionic dispersant with a surface tension of 32 mN / m or more and 51 mN / m or less at 25°C, as measured by the above-described method. This improves its emulsification in water when mixed with an aqueous coating solution and enhances its water dispersion stability. Therefore, it provides good storage stability when the resin composition is prepared. The inventors have previously discovered that anionic dispersants with surface tensions within the aforementioned range are capable of achieving this effect, while anionic, nonionic, cationic, and amphoteric dispersants with surface tensions outside this range cannot fully realize this effect.

[0272] As for the anionic dispersant used, there are no particular limitations as long as it is an anionic dispersant with a surface tension of 32 mN / m or more and 51 mN / m or less at 25°C, as measured by the above-described method. Specifically, examples of anionic dispersants include, for instance, fatty acid salt compounds, alkyl sulfate compounds, polyoxyethylene alkyl ether sulfate salt compounds, polyoxyethylene alkyl ether sulfate compounds, polyoxyethylene polycyclic phenyl ether sulfate compounds, polyoxyethylene alkylene alkenyl ether sulfate compounds, alkylbenzene sulfonate compounds, sulfosuccinate compounds, and alkyl phosphate compounds. Examples of polyoxyethylene alkyl ether sulfate compounds include, for instance, polyoxyethylene alkyl ether ammonium sulfate and polyoxyethylene alkyl ether sodium sulfate. Examples of polyoxyethylene polycyclic phenyl ether sulfate compounds include, for instance, polyoxyethylene polycyclic phenyl ether ammonium sulfate and polyoxyethylene polycyclic phenyl ether sodium sulfate. Examples of polyoxyethylene alkylene alkenyl ether sulfate compounds include, for instance, polyoxyethylene alkylene alkenyl ether ammonium sulfate. Among these, anionic dispersants with a surface tension of 32 mN / m or higher and 51 mN / m or lower at 25°C can be used. Furthermore, one of these anionic dispersants can be used alone, or two or more can be used in combination.

[0273] Among these anionic dispersants, polyoxyethylene polycyclic phenyl ether ammonium sulfate, polyoxyethylene polycyclic phenyl ether sodium sulfate, polyoxyethylene alkyl ether ammonium sulfate, and polyoxyethylene alkyl ether sodium sulfate are particularly preferred.

[0274] The content of the anionic dispersant relative to 100 parts by weight of the capped polyisocyanate is preferably 0.01 parts by weight or more and 5 parts by weight or less, more preferably 0.05 parts by weight or more and 3 parts by weight or less, more preferably 0.10 parts by weight or more and 2 parts by weight or less, and even more preferably 0.14 parts by weight or more and 1.6 parts by weight or less. By setting the content of the anionic dispersant to the lower limit or above, the storage stability of the resin composition can be improved. On the other hand, by setting it to the upper limit or below, the tensile strength of the resin film can be improved.

[0275] <Carboxylates>

[0276] When the aforementioned capping agent comprises (B) a compound having a heterocycle containing one or more nitrogen atoms, the aforementioned capped polyisocyanate composition further comprises a carboxylate.

[0277] Examples of carboxylate salts include quaternary ammonium carboxylate salts that counteract quaternary ammonium ions as cations and metal carboxylate salts that counteract metal ions as cations. From the viewpoint of low-temperature curing properties, metal carboxylate salts are preferred.

[0278] Examples of quaternary ammonium salts (carboxylate salts of quaternary ammonium cations) include, for example, the quaternary ammonium salts shown below.

[0279] (1) Tetramethylammonium, tetraethylammonium, tetrabutylammonium and other tetraalkylammonium acetates, propionates, octanoates, decanoates, myristates, benzoates and other organic weak acid salts.

[0280] (2) Acetates, propionates, octanoates, decanoates, myristates, benzoates and other organic weak acid salts of aryl trialkylammonium such as benzyltrimethylammonium and trimethylphenylammonium.

[0281] (3) Acetates, propionates, octanoates, decanoates, myristates, benzoates and other organic weak acid salts of trimethylhydroxyethylammonium, trimethylhydroxypropylammonium, triethylhydroxyethylammonium, triethylhydroxypropylammonium, etc.

[0282] Examples of metal species that can be used as carboxylic acid metal salts include sodium, potassium, lithium, cesium, nickel, cobalt, cadmium, barium, calcium, zinc, manganese, copper, cerium, zirconium, iron, lead, germanium, antimony, aluminum, titanium, and bismuth. Among these, from the viewpoint of the storage stability of the capped polyisocyanate composition, a monovalent metal is preferred. Furthermore, from the viewpoint of low-temperature curing properties, Group 1 elements such as sodium, potassium, lithium, and cesium are more preferred.

[0283] Carboxylic acid metal salts include both monocarboxylic acids and dicarboxylic acids, such as formic acid, acetic acid, acrylic acid, methacrylic acid, propionic acid, butyric acid, hexanoic acid, octanoic acid, capric acid, stearic acid, oleic acid, eicosanoic acid, myristic acid, benzoic acid, and other aliphatic saturated acids, unsaturated acids, and aromatic acids. From a compatibility perspective, the carboxylic acid in the carboxylic acid metal salt preferably has 1 or more but less than 12 carbon atoms; from a resistance to yellowing of the coating, aliphatic acids with 1 or more but less than 12 carbon atoms are more preferred.

[0284] Preferred carboxylic acid metal salts include, for example, sodium propionate, potassium acetate, potassium propionate, potassium 2-ethylhexanoate, cesium acetate, lithium acetate, bismuth 2-ethylhexanoate, etc., with potassium acetate being the most preferred.

[0285] From the viewpoint of storage stability of the capped polyisocyanate composition, the content of the counter cation of the carboxylate is preferably 0.1% by mass or more and 20% by mass or less relative to the total mass of the capped polyisocyanate, more preferably 0.3% by mass or more and 15% by mass or less, and even more preferably 0.5% by mass or more and 10% by mass or less.

[0286] The content of countercations can be determined by ion chromatography after filtering the aqueous layer obtained by adding ultrapure water to the sample and mixing it. The determination conditions are as shown in the examples.

[0287] <Other Constituents>

[0288] The terminated polyisocyanate composition of this embodiment may further include additives such as solvents, in addition to the above-mentioned terminated polyisocyanate and anionic dispersant.

[0289] Examples of solvents include 1-methylpyrrolidone, ethylene glycol monoethyl ether, diethylene glycol monoethyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, propylene glycol dimethyl ether, methyl ethyl ketone, and acetone. The solvents include methyl isobutyl ketone, propylene glycol monomethyl ether acetate, ethanol, methanol, isopropanol, 1-propanol, isobutanol, 1-butanol, 2-ethylhexanol, cyclohexanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, ethyl acetate, isopropyl acetate, butyl acetate, toluene, xylene, pentane, isopentane, hexane, isohexane, cyclohexane, naphtha, mineral oil, etc. These solvents can be used alone or in combination of two or more. From the viewpoint of dispersibility in water, it is preferable that the solvent has a solubility in water of 5% by mass or more; specifically, dipropylene glycol monomethyl ether is preferred.

[0290] <Method for manufacturing end-capped polyisocyanate compositions>

[0291] The end-capped polyisocyanate composition is not particularly limited, and is obtained by reacting, for example, the above-mentioned polyisocyanate with the above-mentioned end-capping agent.

[0292] The capping reaction of polyisocyanates with capping agents can be carried out regardless of the presence or absence of solvent to obtain capped polyisocyanates.

[0293] It should be noted that the capping agent can be used alone, or one of the compounds (I) or (B) having a heterocycle containing one or more nitrogen atoms, or in combination, two or more of the compounds (I) or (B) having a heterocycle containing one or more nitrogen atoms, or further in combination with other capping agents mentioned above.

[0294] The amount of capping agent added is typically 80 mol% or more and 200 mol% or less relative to the total molar amount of isocyanate groups, preferably 90 mol% or more and 150 mol% or less, and more preferably 93 mol% or more and 130 mol% or less.

[0295] In addition, when using solvents, any solvent that is inert to isocyanate groups is acceptable.

[0296] When using a solvent, the content of non-volatile components from the polyisocyanate and the capping agent is typically 10 parts by mass or more and 95 parts by mass or less relative to 100 parts by mass of the capped polyisocyanate composition, preferably 15 parts by mass or more and 80 parts by mass or less, and more preferably 20 parts by mass or more and 75 parts by mass or less.

[0297] When carrying out the end-capping reaction, organometallic salts of tin, zinc, lead, etc., tertiary amine compounds, and alkali metal alkoxides such as sodium can be used as catalysts.

[0298] The amount of catalyst added varies depending on factors such as the temperature of the end-capping reaction. Generally, it can be 0.05 parts by mass or more and 1.5 parts by mass or less relative to 100 parts by mass of polyisocyanate, preferably 0.1 parts by mass or more and 1.0 parts by mass or less.

[0299] The end-capping reaction can typically be carried out at temperatures above -20°C and below 150°C, preferably above 0°C and below 100°C, and more preferably above 10°C and below 70°C. By setting the end-capping reaction temperature above the aforementioned lower limit, the reaction rate can be further accelerated, and by setting it below the aforementioned upper limit, side reactions can be further suppressed.

[0300] After the end-capping reaction, neutralization can be achieved by adding acidic compounds.

[0301] As the aforementioned acidic compound, either inorganic or organic acids can be used. Examples of inorganic acids include hydrochloric acid, phosphorous acid, and phosphoric acid. Examples of organic acids include methanesulfonic acid, p-toluenesulfonic acid, dioctyl phthalate, and dibutyl phthalate.

[0302] Furthermore, when using hydrophilic compounds and capping agents to manufacture capped polyisocyanate compositions, the above-mentioned polyisocyanate, the above-mentioned hydrophilic compound, and the above-mentioned capping agent are reacted to obtain the composition.

[0303] The reaction of the isocyanate group of the polyisocyanate with the hydrophilic compound and the reaction of the polyisocyanate with the 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 hydrophilic compound is carried out first, and after obtaining the polyisocyanate composition modified with the hydrophilic compound (hereinafter sometimes referred to as "modified polyisocyanate composition"), the reaction of the obtained modified polyisocyanate composition with the capping agent is carried out.

[0304] The reaction of polyisocyanates with hydrophilic compounds can be catalyzed by organometallic salts, tertiary amine compounds, and 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 of the polyisocyanate with 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, there is a tendency to further increase reactivity. Furthermore, by setting the reaction temperature below the upper limit, there is a tendency to more effectively suppress side reactions.

[0306] To prevent the hydrophilic compound from remaining in an unreacted state, it is preferable to allow it to react completely with the polyisocyanate. Because it does not remain in an unreacted state, there is a tendency to more effectively suppress the decrease in the water dispersion stability of the capped polyisocyanate composition and the reduction in low-temperature curability when forming resin films.

[0307] The capping reaction of the modified polyisocyanate composition with the capping agent can be carried out using the method described above as the capping reaction.

[0308] <<Resin Composition>>

[0309] The resin composition of the second embodiment of the present invention comprises the end-capped polyisocyanate composition of the first embodiment described above and a polyhydroxy compound. The resin composition of this embodiment may also be referred to as a single-component resin composition comprising a curing agent component and a main component.

[0310] The resin composition of this embodiment exhibits excellent storage stability and can produce a resin film with excellent low-temperature curing properties.

[0311] The composition of the resin composition of this embodiment will be described in detail below.

[0312] <Polyhydroxy compounds>

[0313] In this specification, "polyhydroxy compound" refers to a compound having at least two hydroxyl groups (hydroxyl groups) in one molecule, also known as "polyol".

[0314] Specifically, examples of the aforementioned polyhydroxy compounds include, for instance, aliphatic hydrocarbon polyols, polyether polyols, polyester polyols, epoxy resins, fluorinated polyols, and acrylic polyols.

[0315] Among them, the preferred polyhydroxy compounds are polyester polyols, fluorinated polyols, or acrylic polyols.

[0316] [Aliphatic hydrocarbon polyols]

[0317] Examples of aliphatic hydrocarbon polyols include, for example, terminally hydroxylated polybutadiene and its hydrogenated derivatives.

[0318] [Polyether polyols]

[0319] As for the aforementioned polyether polyols, examples include polyether polyols obtained by any of the methods described in (1) to (3) below.

[0320] (1) Polyether polyols or polytetramethylene glycols obtained by adding polyols alone or in mixtures to epoxides alone or in mixtures.

[0321] (2) Polyether polyols obtained by reacting polyfunctional compounds with epoxides.

[0322] (3) The so-called polymer polyol obtained by polymerizing acrylamide and the like using the polyether polyol obtained in (1) or (2) as a medium.

[0323] Examples of polyols mentioned above include glycerol and propylene glycol.

[0324] Examples of the aforementioned epoxides include ethylene oxide and propylene oxide.

[0325] Examples of such multifunctional compounds include ethylenediamine and ethanolamines.

[0326] [Polyester polyols]

[0327] As for the aforementioned polyester polyols, examples include any of the polyester polyols listed in (1) or (2) below.

[0328] (1) Polyester polyol resins obtained by condensation reaction of one or more dicarboxylic acids with one or more polyols.

[0329] (2) Polycaprolactones obtained by ring-opening polymerization of ε-caprolactone with polyols.

[0330] Examples of the aforementioned dicarboxylic acids include succinic acid, adipic acid, dimer acids, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, and 1,4-cyclohexanedicarboxylic acid.

[0331] Examples of the aforementioned polyols include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, trimethylolpropane, glycerol, pentaerythritol, 2-hydroxymethylpropanediol, and ethoxylated trimethylolpropane.

[0332] [Epoxy Resin]

[0333] Examples of epoxy resins mentioned above include phenolic varnish-type epoxy resins, β-methylepichlool-type epoxy resins, cyclic ethylene oxide-type epoxy resins, glycidyl ether-type epoxy resins, glycol ether-type epoxy resins, epoxy-type aliphatic unsaturated compounds, epoxidized fatty acid esters, ester-type polycarboxylic acids, amino-glycidyl-type epoxy resins, halogenated epoxy resins, resorcinol-type epoxy resins, and resins obtained by modifying these epoxy resins with amino compounds, polyamide compounds, etc.

[0334] [Fluorine-containing polyols]

[0335] Examples of the aforementioned fluorinated polyols include copolymers of fluoroolefins, cyclohexyl vinyl ethers, hydroxyalkyl vinyl ethers, and monocarboxylic acid vinyl esters disclosed in references 1 (Japanese Patent Application Publication No. 57-34107) and 2 (Japanese Patent Application Publication No. 61-275311).

[0336] [Acrylic polyols]

[0337] The aforementioned acrylic polyols can be obtained by polymerizing, for example, 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 other monomers that can copolymerize with the polymerizable monomer as needed.

[0338] As polymerizable monomers having one or more active hydrogen atoms in one of the aforementioned molecule, examples include those shown in (i) to (iii) below. They can be used alone or in combination of two or more.

[0339] (i) Acrylates with active hydrogen, such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxybutyl acrylate.

[0340] (ii) Methacrylates with active hydrogen, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and 2-hydroxybutyl methacrylate.

[0341] (iii) (meth)acrylates containing polyvalent active hydrogens, such as glycerol monoacrylate or methacrylate monoacrylate, trimethylolpropane monoacrylate or methacrylate monoacrylate.

[0342] Other monomers that can copolymerize with the aforementioned polymerizable monomers include, for example, those shown in (i) to (v) below. They can be used alone or in combination of two or more.

[0343] (i) Acrylates such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate.

[0344] (ii) Methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, glycidyl methacrylate, and other methacrylates.

[0345] (iii) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid.

[0346] (iv) Unsaturated amides such as acrylamide, N-hydroxymethylacrylamide, and diacetone acrylamide.

[0347] (v) Styrene, vinyltoluene, vinyl acetate, acrylonitrile, etc.

[0348] In addition, examples include acrylic polyols obtained by copolymerizing polymerizable UV-stabilized monomers, as disclosed in references 3 (Japanese Patent Application Publication No. 1-261409) and 4 (Japanese Patent Application Publication No. 3-006273).

[0349] Specifically, examples of polymerizable UV-stabilized monomers include 4-(meth)acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 1-crotonyl-4-crotonyloxy-2,2,6,6-tetramethylpiperidine, and 2-hydroxy-4-(3-methacryloyloxy-2-hydroxypropoxy)benzophenone.

[0350] For example, acrylic polyols can be obtained by solution polymerization of the above-mentioned monomer components in the presence of known free radical polymerization initiators such as peroxides and azo compounds, and then diluted with organic solvents as needed.

[0351] In the case of obtaining aqueous-based acrylic polyols, they can be manufactured by known methods such as solution polymerization of olefinic unsaturated compounds to convert them into an aqueous layer, or emulsion polymerization. In this case, water solubility or water dispersibility can be imparted by neutralizing the acidic portions of monomers containing carboxylic acids, such as acrylic acid and methacrylic acid, or monomers containing sulfonic acids, with amines or ammonia.

[0352] [NCO / OH]

[0353] The molar equivalent ratio (NCO / OH) of the isocyanate group in the end-capped polyisocyanate composition to the hydroxyl group of the polyhydroxy compound contained in the resin composition of this embodiment is determined according to the desired properties of the resin film, and is generally 0.01 or more and 22.5 or less.

[0354] Glass transition temperature

[0355] The glass transition temperature of the polyhydroxy compound is preferably 0°C or higher and 100°C or lower, more preferably 0°C or higher and 90°C or lower, even more preferably 0°C or higher and 80°C or lower, and particularly preferably 5°C or higher and 70°C or lower. By keeping the glass transition temperature of the polyhydroxy compound within the above range, a resin film with superior tensile strength can be obtained. The glass transition temperature of the polyhydroxy compound can be determined using, for example, the method described in the examples below.

[0356] [Weight-average molecular weight]

[0357] The preferred weight-average molecular weight of the polyhydroxy compound is 5.0 × 10⁻⁶. 3 Above and 2.0×10 5 Hereinafter, 5.0 × 10 is preferred. 3 Above and 1.5×10 5 The following is a further preferred value: 5.0 × 10 3 Above and 1.0×10 5The following describes how, by ensuring the weight-average molecular weight of the polyhydroxy compound is within the aforementioned range, resin films with superior tensile strength and other physical properties can be obtained. The weight-average molecular weight of the polyhydroxy compound is a polystyrene-based weight-average molecular weight determined, for example, by gel permeation chromatography (GPC). Specifically, it can be determined using the methods described in the examples below.

[0358] [Hydroxy value]

[0359] The hydroxyl value of the polyhydroxy compound is preferably 30 mg KOH / g or more and 250 mg KOH / g or less, more preferably 40 mg KOH / g or more and 200 mg KOH / g or less, and even more preferably 45 mg KOH / g or more and 180 mg KOH / g or less. By keeping the hydroxyl value of the polyhydroxy compound within the above range, resin films with superior tensile strength and other physical properties can be obtained. The hydroxyl value of the polyhydroxy compound can be determined using, for example, the method described in the examples below.

[0360] The content of the capped polyisocyanate in the resin composition of this embodiment is preferably 5 parts by mass and 200 parts by mass or less relative to 100 parts by mass of the polyhydroxy compound, more preferably 6 parts by mass and 180 parts by mass or less, and even more preferably 10 parts by mass and 150 parts by mass or less. By keeping the content of the capped polyisocyanate within the above range, a resin film with superior tensile strength and other physical properties can be obtained. The content of the capped polyisocyanate can also be calculated by, for example, the mixing amount, or it can be determined and quantified using nuclear magnetic resonance (NMR) and gas chromatography / mass spectrometry (GC / MS).

[0361] <Other Additives>

[0362] The resin composition of this embodiment may further contain other additives.

[0363] Other additives include curing agents, curing catalysts, solvents, pigments (extender pigments, coloring pigments, metallic pigments, etc.) that can react with the cross-linking functional groups in polyhydroxy compounds, ultraviolet absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents that inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, film-forming aids, etc.

[0364] Examples of curing agents mentioned above include melamine resin, urea resin, epoxy-containing compounds or resins, carboxyl-containing compounds or resins, acid anhydrides, alkoxysilyl-containing compounds or resins, and hydrazide compounds.

[0365] The aforementioned curing catalyst can be either a basic compound or a Lewis acid compound.

[0366] Examples of the aforementioned basic compounds include, for example, metal hydroxides, metal alkoxides, metal carboxylates, metal acetylacetonates, hydroxides of onium salts, onium carboxylates, halides of onium salts, metal salts of active methylene compounds, onium salts of active methylene compounds, aminosilanes, amines, and phosphines. Among the aforementioned onium salts, ammonium salts, phosphonium salts, or sulfonium salts are suitable.

[0367] Examples of Lewis acidic compounds include organotin compounds, organozinc compounds, organotitanium compounds, and organozirconium compounds.

[0368] As the aforementioned solvent, solvents identical to those exemplified in the above-described capped polyisocyanate compositions can be listed.

[0369] In addition, known substances can be appropriately selected and used as pigments (extender pigments, coloring pigments, metallic pigments, etc.), ultraviolet absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents that inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, and film-forming aids.

[0370] <Method for manufacturing resin composition>

[0371] The resin composition of this embodiment can be used in both solvent-based and aqueous-based matrices. However, resin compositions with good storage stability in aqueous matrices and excellent low-temperature curing properties below 80°C when forming resin films are currently unknown. Therefore, resin compositions suitable for use in aqueous matrices are not yet available.

[0372] In manufacturing a water-based resin composition (water-based resin composition), firstly, additives such as curing agents, curing catalysts, solvents, pigments (extender pigments, coloring pigments, metallic pigments, etc.), ultraviolet absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents to inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, and film-forming aids are added as needed. Next, the aforementioned end-capped polyisocyanate composition or its water dispersion is added as a curing agent, and water and solvent are further added as needed to adjust the viscosity. Then, by forced stirring using a stirring device, a water-based resin composition (water-based resin composition) can be obtained.

[0373] When manufacturing a solvent-based resin composition, firstly, additives such as curing agents, curing catalysts, solvents, pigments (extender pigments, coloring pigments, metallic pigments, etc.), UV absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents to inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, and film-forming aids are added to the polyhydroxy compound or its solvent dilution as needed. Next, the aforementioned end-capped polyisocyanate composition is added as a curing agent, and solvent is further added as needed to adjust the viscosity. Then, by stirring using a manual stirrer or a stirring device, a solvent-based resin composition can be obtained.

[0374] <<Resin Film>>

[0375] The resin film of the third embodiment of the present invention is formed by curing the resin composition of the second embodiment described above. The resin film of this embodiment has good low-temperature curing properties.

[0376] The resin film of this embodiment can be obtained by coating the above-mentioned resin composition onto a substrate using known methods such as roller coating, curtain coating, spraying, bell gun coating, and electrostatic coating, and then heating it to cure it.

[0377] From the viewpoint of energy saving and heat resistance of the substrate, the heating temperature is preferably about 60°C or higher and about 120°C or lower, more preferably about 65°C or higher and about 110°C or lower, and even more preferably about 70°C or higher and about 100°C or lower.

[0378] From the viewpoint of energy saving and heat resistance of the substrate, the heating time is preferably about 1 minute or more and about 60 minutes or less, more preferably about 2 minutes or more and about 40 minutes or less.

[0379] The substrate is not particularly limited, and examples include the outer panel of a car body such as a car, truck, motorcycle, or bus; car parts such as bumpers; the outer panel of a household electrical product such as a mobile phone or audio equipment; and various films, among which the outer panel of a car body or a car part is preferred.

[0380] The material of the substrate is not particularly limited, and can include metal materials such as iron, aluminum, brass, copper, tinplate, stainless steel, galvanized steel, and galvanized alloy (Zn-Al, Zn-Ni, Zn-Fe, etc.) steel; resins such as polyethylene resin, polypropylene resin, acrylonitrile-butadiene-styrene (ABS) resin, polyamide resin, acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, and epoxy resin; various FRP and other plastic materials; inorganic materials such as glass, cement, and concrete; and fibrous materials such as wood, paper, and cloth. Among these, metal materials or plastic materials are preferred.

[0381] The substrate can be a substrate obtained by performing surface treatments such as phosphate treatment, chromate treatment, or composite oxide treatment on the surface of the aforementioned metal material or the metal surface of a vehicle body or the like formed from the aforementioned metal material, and then a coating film can be formed on it. As a substrate with a coating film, it can be a product obtained by performing surface treatment as needed and forming a primer coating film thereon, for example, a vehicle body with a primer coating film formed by electrodeposition of a coating. The substrate can also be a substrate obtained by performing a desired surface treatment on the surface of the aforementioned plastic material or the plastic surface of an automotive part or the like formed from the aforementioned plastic material. Furthermore, the substrate can combine plastic and metal materials.

[0382] As shown in the examples described later, the resin film of this embodiment, which is a 40 μm thick resin film obtained by curing the above-described resin composition at 80°C for 30 minutes, and then kept at 23°C for one week, has a gelation rate of 80% by mass or more, more preferably 84% by mass or more, and even more preferably 86% by mass or more when immersed in acetone at 23°C for 24 hours. By setting the gelation rate to the lower limit value mentioned above, better low-temperature curing properties can be achieved. On the other hand, the upper limit value of the gelation rate is not particularly limited and can be set to, for example, 100% by mass. The specific method for measuring the gelation rate can be, for example, the method shown in the examples described later.

[0383] As shown in the embodiments described later, the resin film of this embodiment, which is a resin film with a thickness of 40 μm, a width of 10 mm, and a length of 40 mm, formed by curing the above-mentioned resin composition at 80°C for 30 minutes, is set with a clamp spacing of 20 mm. The maximum stress (tensile strength) in a tensile test performed at a speed of 20 mm / min is preferably 5 MPa or more, more preferably 10 MPa, and even more preferably 15 MPa or more. On the other hand, the upper limit of the maximum stress is not particularly limited and can be, for example, 80 MPa or 70 MPa. The specific method for measuring the maximum stress can be, for example, the method shown in the embodiments described later.

[0384] The resin film of this embodiment is suitable for use as a coating for products in various fields seeking energy conservation and for materials with low heat resistance due to its excellent low-temperature curing properties.

[0385] <<Layered Structures>>

[0386] The laminate of the fourth embodiment of the present invention comprises two or more resin films of different compositions as described in the third embodiment. Furthermore, the average thickness of each layer of the laminate of this embodiment is 1 μm or more and 50 μm or less. The laminate of this embodiment exhibits excellent low-temperature curing properties due to the inclusion of the aforementioned resin film.

[0387] The laminate in this embodiment may also include two or more layers of the above-described resin film with the same composition.

[0388] Furthermore, the laminate of this embodiment is formed by laminating various coatings containing the above-mentioned resin film onto the substrate.

[0389] Examples of materials to be bonded include glass, various metals, porous components, components coated with various finishes, cured sealant materials, rubber, leather, fibers, non-woven fabrics, resin films and sheets, UV-curable acrylic resin layers, and layers formed from inks. Examples of the aforementioned metals include aluminum, iron, zinc-coated steel sheets, copper, and stainless steel. Examples of the aforementioned porous components include wood, paper, mortar, and stone. Examples of the aforementioned coatings include fluoropolymer coatings, urethane coatings, and acrylic urethane coatings. Examples of the aforementioned cured sealant materials include silicone-based, modified silicone-based, and urethane-based materials. Examples of the aforementioned rubbers include natural rubber and synthetic rubber. Examples of the aforementioned leathers include natural leather and artificial leather. Examples of the aforementioned fibers include plant fibers, animal fibers, carbon fibers, and glass fibers. Examples of resins that can be used as raw materials for the aforementioned resin-based films and sheets include, for example, polyvinyl chloride, polyester, acrylics, polycarbonate, triacetyl cellulose, and polyolefins. Examples of inks include, for example, printing inks and UV inks.

[0390] The laminate of this embodiment can be obtained by applying the above-mentioned resin compositions of different compositions to the substrate using known methods such as roller coating, curtain coating, spraying, bell gun coating, and electrostatic coating, and then heating and curing them separately, or by heating and curing all layers together after coating.

[0391] The laminate of this embodiment, in addition to including the above-described resin film, may include layers formed of other known components, such as a primer layer, an adhesive layer, and a decorative layer.

[0392] <<Hydrophilic Polyisocyanate Compositions>>

[0393] The hydrophilic polyisocyanate composition of the fifth embodiment is derived from a hydrophilic compound and an alicyclic polyisocyanate having isocyanurate groups. That is, the hydrophilic polyisocyanate composition of this embodiment comprises a reaction product of a hydrophilic compound and an alicyclic polyisocyanate, namely, a hydrophilic polyisocyanate. The proportion of isocyanate groups modified with the aforementioned hydrophilic compound is 2 mol% or more and 15 mol% or less, relative to the total molar amount of isocyanate groups in the aforementioned alicyclic polyisocyanate.

[0394] The hydrophilic polyisocyanate composition of this embodiment has good water dispersibility due to the above-described structure, and exhibits excellent hardness when formed into a resin film.

[0395] The hydrophilic group is introduced by reacting the hydrophilic compound with an alicyclic isocyanate monomer, or by reacting the hydrophilic compound with an alicyclic polyisocyanate. In the hydrophilic polyisocyanate composition of this embodiment, the ratio of the isocyanate group modified with the aforementioned hydrophilic compound to the total molar amount of isocyanate groups in the alicyclic polyisocyanate can be described as: the ratio of isocyanate groups modified with the hydrophilic compound to 100 mol% of the isocyanate groups in the alicyclic polyisocyanate used as a raw material (hereinafter sometimes referred to as "modification rate"), or it can be described as: the ratio of isocyanate groups with the aforementioned hydrophilic group introduced to the total molar amount of isocyanate groups with and without the aforementioned hydrophilic group introduced.

[0396] The modification rate is 2 mol% or more and 15 mol% or less, preferably 3 mol% or more and 14 mol% or less, more preferably 4 mol% or more and 12 mol% or less, and even more preferably 5 mol% or more and 10 mol% or less.

[0397] By keeping the modification rate within the above-mentioned range, good water dispersibility and excellent hardness are achieved when the resin film is formed. Furthermore, as shown in the examples described later, when the hydrophilic polyisocyanate composition of this embodiment is made into a capped polyisocyanate composition by setting it to the lower limit value or above, there is a tendency for better curing properties at low temperatures of around 80°C when forming the resin film.

[0398] The modification rate can be determined using the following method. Specifically, it is determined by the peak area ratio of unmodified alicyclic polyisocyanates, monomodified alicyclic polyisocyanates, dimodified alicyclic polyisocyanates, and trimodified alicyclic polyisocyanates at 220 nm using liquid chromatography (LC). The measuring apparatus and conditions can be set, for example, as follows.

[0399] (Apparatus and Measurement Conditions)

[0400] LC device: Waters Corporation, UPLC (trade name)

[0401] Column: Waters Corporation, ACQUITY UPLC HSS T3 1.8μm C18, inner diameter 2.1mm × length 50mm

[0402] Flow rate: 0.3 mL / min

[0403] Mobile phase: A = 10 mM ammonium acetate aqueous solution, B = acetonitrile

[0404] Gradient conditions: The initial mobile phase composition is A / B = 98 / 2. After sample injection, the ratio of B increases linearly, and after 10 minutes, A / B = 0 / 100 is set.

[0405] Detection method: photodiode array detector, measurement wavelength 220nm

[0406] Next, each component of the hydrophilic polyisocyanate composition of this embodiment will be described in detail below.

[0407] Alicyclic polyisocyanates

[0408] Alicyclic polyisocyanates are reactants obtained by reacting multiple monomeric compounds (hereinafter sometimes referred to as "alicyclic isocyanate monomers") having one or more isocyanate groups (-NCO) and whose backbone is composed of alicyclic hydrocarbon groups. These reactants contain isocyanurate groups. The "isocyanurate group" mentioned here refers to the functional group formed by the cyclization and trimerization of three isocyanate groups.

[0409] The alicyclic isocyanate monomers are preferably monomers with 4 or more but less than 30 carbon atoms. Specifically, examples of alicyclic isocyanate monomers include isophorone diisocyanate (hereinafter sometimes referred to as "IPDI"), 1,3-bis(diisocyanate-methyl)cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, diisocyanate-norbornane, and di(isocyanate-methyl)norbornane. These alicyclic isocyanate monomers can be used alone or in combination of two or more. Among these, alicyclic polyisocyanates are preferably polyisocyanates derived from IPDI and containing isocyanurate groups.

[0410] Alicyclic polyisocyanates may have functional groups other than the isocyanurate group, without impairing their effectiveness; preferably, they may only have the isocyanurate group. Examples of functional groups other than the isocyanurate group include urea carbamate group, urea diketone group, iminooxadiazine diketone group, carbamate group, and biuret group.

[0411] <Other Polyisocyanates>

[0412] The hydrophilic polyisocyanate composition of this embodiment may contain other polyisocyanates besides alicyclic polyisocyanates to a extent that does not impair its effectiveness, preferably only alicyclic polyisocyanates.

[0413] Other polyisocyanates are reactants obtained by reacting multiple monomeric compounds (hereinafter sometimes referred to as "aliphatic isocyanate monomers" or "aromatic isocyanate monomers") having one or more isocyanate groups (-NCO) and whose skeletons are composed of aliphatic or aromatic hydrocarbon groups. Other polyisocyanates may or may not have isocyanurate groups.

[0414] Examples of aliphatic isocyanate monomers include aliphatic diisocyanates and aliphatic triisocyanates. Examples of aliphatic diisocyanates include 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (hereinafter sometimes referred to as "HDI"), 2,2,4-trimethyl-1,6-diisocyanohexane, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, 2-methylpentane-1,5-diisocyanate (MPDI), and lysine diisocyanate (hereinafter sometimes referred to as "LDI"). Examples of aliphatic triisocyanates include 4-isocyanate-methyl-1,8-octamethylene diisocyanate (hereinafter sometimes referred to as "NTI"), 1,3,6-hexamethylene triisocyanate (hereinafter sometimes referred to as "HTI"), bis(2-isocyanoethyl)-2-isocyanoglutarate (hereinafter sometimes referred to as "GTI"), and lysine triisocyanate (hereinafter sometimes referred to as "LTI"). Examples of aromatic isocyanate monomers include diphenylmethane-4,4'-diisocyanate (MDI), 1,5-naphthalene diisocyanate, toluene diisocyanate (TDI), phenyldimethyl diisocyanate, and m-tetramethylphenyldimethyl diisocyanate (TMXDI).

[0415] <Hydrophilic compounds>

[0416] A hydrophilic compound is a compound having a hydrophilic group. Preferably, in addition to having a hydrophilic group, the hydrophilic compound has one or more active hydrogen groups relative to one molecule of the hydrophilic compound, which can react with at least one isocyanate group of an alicyclic polyisocyanate. Specifically, active hydrogen groups can be listed as hydroxyl, mercapto, carboxylic acid, amino, and thiol groups.

[0417] Examples of hydrophilic compounds include nonionic compounds, cationic compounds, and anionic compounds. These hydrophilic compounds can be used individually or in combination of two or more. From the viewpoint of ease of acquisition and minimal electrical interaction with the compound, nonionic compounds are preferred as hydrophilic compounds, while anionic compounds are preferred from the viewpoint of suppressing a decrease in the hardness of the resulting resin film.

[0418] (Nonionic compounds)

[0419] Specifically, nonionic compounds include monools and compounds obtained by adding ethylene oxide to the hydroxyl groups of alcohols. Examples of monools include methanol, ethanol, and butanol. Examples of compounds obtained by adding ethylene oxide to the hydroxyl groups of alcohols include ethylene glycol, diethylene glycol, polyethylene glycol, and polyethylene glycol monomethyl ether. These nonionic compounds also possess active hydrogen groups that react with isocyanate groups.

[0420] Among them, as a nonionic compound, even a small amount can improve the water dispersibility of the hydrophilic polyisocyanate composition. Therefore, polyethylene glycol monoalkyl ether obtained by adding ethylene oxide to the hydroxyl group of a monool is preferred.

[0421] The number of ethylene oxide additions in the compound containing ethylene oxide is preferably 4 or more and 30 or less, more preferably 4 or more and 25 or less. By setting the number of ethylene oxide additions to the lower limit or above, there is a tendency to more effectively impart water dispersibility to the hydrophilic polyisocyanate composition; by setting the number of ethylene oxide additions to the upper limit or below, there is a tendency to make it less likely for hydrophilic polyisocyanate composition precipitates to form during low-temperature storage.

[0422] From the viewpoint of the water dispersion stability of the hydrophilic polyisocyanate composition, the lower limit of the amount of nonionic hydrophilic groups added to the alicyclic polyisocyanate (hereinafter sometimes referred to as "the content of nonionic hydrophilic groups") is preferably 1% by mass, more preferably 2% by mass, further preferably 3% by mass, and particularly preferably 4% by mass relative to the mass of the solid component of the hydrophilic polyisocyanate composition.

[0423] Furthermore, from the viewpoint of the water resistance of the resulting resin film, the upper limit of the content of nonionic hydrophilic groups is preferably 55% by mass, more preferably 50% by mass, further preferably 48% by mass, and particularly preferably 44% by mass relative to the solid content of the hydrophilic polyisocyanate composition.

[0424] That is, the content of nonionic hydrophilic groups relative to the solid component mass of the hydrophilic polyisocyanate composition is preferably 1% or more and 55% or less by mass, more preferably 2% or more and 50% or less by mass, further preferably 3% or more and 48% or less by mass, and particularly preferably 4% or more and 44% or less by mass.

[0425] By keeping the content of nonionic hydrophilic groups within the above range, there is a tendency to further disperse the hydrophilic polyisocyanate composition in water to obtain a homogeneous film.

[0426] (Catonic compounds)

[0427] Specifically, compounds possessing both cationic hydrophilic groups and active hydrogen groups can be listed as cationic compounds. Furthermore, compounds possessing active hydrogen groups such as glycidyl groups can be combined with compounds possessing cationic hydrophilic groups such as sulfides and phosphine to form hydrophilic compounds. In this case, the compound possessing isocyanate groups is first reacted with the compound possessing active hydrogen groups to add functional groups such as glycidyl groups, and then the sulfide, phosphine, etc., are reacted. From the viewpoint of ease of manufacture, compounds possessing both cationic hydrophilic groups and active hydrogen groups are preferred.

[0428] Compounds possessing both cationic hydrophilic groups and active hydrogen groups include, specifically, dimethylethanolamine, diethylethanolamine, diethanolamine, and methyldiethanolamine. Furthermore, tertiary amino groups formed by addition reactions using these compounds can also be quaternized using, for example, dimethyl sulfate or diethyl sulfate.

[0429] The reaction between cationic compounds and alicyclic polyisocyanates can occur in the presence of a solvent. The solvent is preferably free of active hydrogen groups; examples include ethyl acetate, propylene glycol monomethyl ether acetate, and dipropylene glycol dimethyl ether.

[0430] The cationic hydrophilic group added to the alicyclic polyisocyanate is preferably neutralized using a compound having an anionic group. Specifically, examples of such anionic groups include carboxyl groups, sulfonic acid groups, phosphate groups, halogen groups, and sulfate groups.

[0431] Compounds containing a carboxyl group include, specifically, formic acid, acetic acid, propionic acid, butyric acid, and lactic acid.

[0432] Compounds containing sulfonic acid groups include, for example, ethanesulfonic acid.

[0433] Compounds containing a phosphate group include, specifically, phosphoric acid and acid phosphate esters.

[0434] Compounds containing halogen groups include, for example, hydrochloric acid.

[0435] Compounds containing a sulfuric acid group include, specifically, sulfuric acid.

[0436] Among them, the compound having an anionic group is preferably a compound having a carboxyl group, and more preferably acetic acid, propionic acid or butyric acid.

[0437] (Anionic compounds)

[0438] As anionic hydrophilic groups, specifically, carboxyl groups, sulfonic acid groups, phosphate groups, halogen groups, and sulfate groups can be listed.

[0439] As anionic compounds, specifically, compounds that simultaneously possess anionic groups and active hydrogen groups can be listed; more specifically, compounds that, for example, possess a carboxyl group of a monohydroxycarboxylic acid or a polyhydroxycarboxylic acid as anionic groups can be listed.

[0440] Examples of monohydroxycarboxylic acids include 1-hydroxyacetic acid, 3-hydroxypropionic acid, 12-hydroxy-9-octadecanoic acid, hydroxypentanoic acid (hydroxypentanoic acid), and lactic acid.

[0441] Compounds containing a carboxyl group of a polyhydroxycarboxylic acid as an anionic group include, for example, dihydroxymethylacetic acid, 2,2-dihydroxymethylbutyric acid, 2,2-dihydroxymethylvalerate, dihydroxysuccinic acid, and dihydroxymethylpropionic acid.

[0442] In addition, compounds that have both sulfonic acid groups and active hydrogen groups can be listed, and more specifically, hydroxyethanesulfonic acid can be listed as an example.

[0443] Among them, hydroxypentanoic acid or dimethylolpropionic acid are preferred as compounds that simultaneously possess anionic groups and active hydrogen groups.

[0444] The anionic hydrophilic group added to alicyclic polyisocyanates is preferably neutralized using amine compounds, which are basic substances.

[0445] As amine compounds, examples include ammonia and water-soluble amino compounds.

[0446] Specifically, 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. Tertiary amines such as triethylamine and dimethylethanolamine can also be used. These amine compounds can be used alone or in combination of two or more.

[0447] <Method for manufacturing hydrophilic polyisocyanate compositions>

[0448] The method for manufacturing the hydrophilic polyisocyanate composition of this embodiment is not particularly limited, and examples include: (i) a method of prepolymerizing an alicyclic isocyanate monomer and then reacting the resulting prepolymer with a hydrophilic compound; or (ii) a method of reacting an alicyclic isocyanate monomer with a hydrophilic compound, etc. Among these, method (i) is preferred.

[0449] As a method for prepolymerizing alicyclic isocyanate monomers to obtain prepolymers with isocyanurate groups, an isocyanurate esterification reaction catalyst can be used, for example.

[0450] There are no particular limitations on the catalyst used for the isocyanurate esterification reaction, but it is generally preferred to be basic. Specifically, catalysts such as those shown below can be listed as catalysts for the isocyanurate esterification reaction.

[0451] 1) Hydroxides of tetraalkylammonium such as tetramethylammonium, tetraethylammonium, and tetrabutylammonium; and organic weak acid salts such as acetate, propionate, octanoate, decanoate, myristate, and benzoate of the aforementioned tetraalkylammonium.

[0452] 2) Hydroxides of aryltrialkylammonium such as benzyltrimethylammonium and trimethylphenylammonium; and organic weak acid salts such as acetate, propionate, octanoate, decanoate, myristate, and benzoate of the aforementioned aryltrialkylammonium.

[0453] 3) Hydroxides of hydroxyalkylammonium such as trimethylhydroxyethylammonium, trimethylhydroxypropylammonium, triethylhydroxyethylammonium, and triethylhydroxypropylammonium; and organic weak acid salts such as acetates, propions, octanoates, decanoates, myristates, and benzoates of the aforementioned hydroxyalkylammonium.

[0454] 4) Metal salts of alkyl carboxylic acids such as acetic acid, propionic acid, hexanoic acid, octanoic acid, decanoic acid, and myristic acid, such as tin, zinc, and lead.

[0455] 5) Alkoxides of metals such as sodium and potassium.

[0456] 6) Compounds containing aminosilyl groups, such as hexamethylenedisilazane.

[0457] 7) Mannich bases.

[0458] 8) Mixtures of tertiary amines and epoxides.

[0459] 9) Phosphorus compounds such as tributylphosphine.

[0460] From the viewpoint of minimizing the generation of unwanted byproducts, the preferred catalyst for the isocyanurate esterification reaction is a quaternary ammonium hydroxide or an organic weak acid salt of quaternary ammonium, more preferably a tetraalkylammonium hydroxide, an organic weak acid salt of tetraalkylammonium, an aryltrialkylammonium hydroxide, or an organic weak acid salt of aryltrialkylammonium.

[0461] The upper limit of the amount of the catalyst used in the isocyanurate esterification reaction is preferably 1000 ppm by mass relative to the mass of the added alicyclic isocyanate monomer, more preferably 500 ppm by mass, and even more preferably 100 ppm by mass.

[0462] On the other hand, there is no particular limit to the lower limit of the amount of the catalyst used in the above-mentioned isocyanurate esterification reaction, which can be, for example, 10 ppm by mass.

[0463] The isocyanurate esterification reaction temperature is preferably 50°C or higher and 120°C or lower, more preferably 55°C or higher and 90°C or lower. By setting the isocyanurate esterification reaction temperature to the above-mentioned upper limit or lower, there is a tendency to more effectively suppress the coloring of the prepolymer, etc.

[0464] At the point when the desired conversion rate (the ratio of the mass of the prepolymer generated in the isocyanurate esterification reaction to the mass of the alicyclic isocyanate monomer added) is reached, the isocyanurate esterification reaction is stopped by adding an acidic compound (e.g., phosphoric acid, acid phosphate, etc.).

[0465] It should be noted that to obtain the prepolymer, the reaction needs to be stopped at the initial stage. However, the isocyanurate esterification reaction is very rapid in the initial stage, making it difficult to stop the reaction at this stage. Careful selection of reaction conditions, especially the amount and method of catalyst addition, is necessary. For example, adding the catalyst in stages at regular intervals is recommended as a suitable method.

[0466] Therefore, the conversion rate of the isocyanurate esterification reaction used to obtain the prepolymer is preferably 10% or more and 60% or less, more preferably 15% or more and 55% or less, and even more preferably 20% or more and 50% or less.

[0467] By reducing the conversion rate of the isocyanurate esterification reaction to below the upper limit mentioned above, the viscosity of the hydrophilic polyisocyanate composition can be lowered. Furthermore, by reducing the conversion rate of the isocyanurate esterification reaction to above the lower limit mentioned above, the reaction cessation operation can be performed more easily.

[0468] In addition, when deriving prepolymers containing isocyanurate groups, alcohols with more than one nucleotide and less than six nucleotides can be used, in addition to the aforementioned alicyclic isocyanate monomers.

[0469] Examples of usable alcohols with a 1- or higher but less than 6-membered group include, for example, non-polymerizable alcohols and polymerizable alcohols. Here, "non-polymerizable alcohols" refers to alcohols that do not possess polymerizable groups. On the other hand, "polymerizable alcohols" refer to alcohols obtained by polymerizing monomers that possess polymerizable groups and hydroxyl groups.

[0470] As non-polymerizable alcohols, examples include monools, diols, triols, tetraols, and other polyols.

[0471] Examples of monools include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, n-pentanol, n-hexanol, n-octanol, n-nonanol, 2-ethylbutanol, 2,2-dimethylhexanol, 2-ethylhexanol, cyclohexanol, methylcyclohexanol, and ethylcyclohexanol.

[0472] 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.

[0473] Examples of triols include glycerol and trimethylolpropane.

[0474] Examples of tetraols include pentaerythritol.

[0475] As a polymerizable alcohol, there are no particular limitations; examples include polyester polyols, polyether polyols, acrylic polyols, and polyolefin polyols.

[0476] As a type of polyester polyol, there are no particular limitations, and examples include products obtained by condensation reactions of dicarboxylic acids alone or in mixtures with polyols alone or in mixtures.

[0477] As a dicarboxylic acid, there are no particular limitations, but at least one dicarboxylic acid can be listed, for example, from the group consisting of carboxylic acids such as succinic acid, adipic acid, sebacic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, and terephthalic acid.

[0478] As a polyol, there is no particular limitation, and examples include at least one polyol selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, neopentyl glycol, trimethylolpropane and glycerol.

[0479] In addition, examples of polyester polyols include polycaprolactones obtained by ring-opening polymerization of ε-caprolactone using the aforementioned polyols.

[0480] As for polyether polyols, there are no particular limitations. Examples include polyether polyols obtained by adding one or a mixture of epoxides to polyols using alkali metal hydroxides or strong alkaline catalysts; polyether polyols obtained by reacting epoxides with polyamine compounds; and so-called polymer polyols obtained by polymerizing acrylamide and the like using the above-mentioned polyethers as a medium.

[0481] Examples of alkali metals include lithium, sodium, and potassium.

[0482] Examples of strong basic catalysts include alkoxides and alkylamines.

[0483] As polyols, examples of polyols that are the same as those exemplified in the above-mentioned polyester polyols can be listed.

[0484] Examples of epoxides include ethylene oxide, propylene oxide, butane oxide, cyclohexane oxide, and phenylene oxide.

[0485] Examples of polyamine compounds include ethylenediamines.

[0486] As an acrylic polyol, there are no particular limitations, and examples include substances obtained by copolymerizing one or a mixture of monomers containing olefinic unsaturated bonds with hydroxyl groups with one or a mixture of other monomers containing olefinic unsaturated bonds that can be copolymerized with them.

[0487] As monomers containing hydroxyl groups and olefinic unsaturated bonds, there are no particular limitations, and examples include hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate.

[0488] Other monomers containing olefinic unsaturated bonds that can copolymerize with monomers containing olefinic unsaturated bonds having hydroxyl groups are not particularly limited, and examples include acrylates, methacrylates, unsaturated carboxylic acids, unsaturated amides, vinyl monomers, and vinyl monomers having hydrolyzable silyl groups.

[0489] Examples of acrylates include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, benzyl acrylate, and phenyl acrylate.

[0490] Examples of methacrylates include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, benzyl methacrylate, and phenyl methacrylate.

[0491] Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, and itaconic acid.

[0492] Examples of unsaturated amides include acrylamide, methacrylamide, N,N-methylenebisacrylamide, diacetone acrylamide, diacetone methacrylamide, maleic acid amide, and maleimide.

[0493] Examples of vinyl monomers include glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, and dibutyl fumarate.

[0494] Examples of vinyl monomers with hydrolyzable silyl groups include vinyltrimethoxysilane, vinylmethyldimethoxysilane, and γ-(meth)acryloyloxypropyltrimethoxysilane.

[0495] Examples of polyolefin polyols include terminally hydroxylated polybutadiene and its hydrogenated derivatives.

[0496] Prepolymers can be obtained by removing unreacted alicyclic isocyanate monomers from the reaction solution after the reaction is completed through methods such as thin-film distillation and extraction.

[0497] In the reaction of prepolymers with hydrophilic compounds, organometallic salts, tertiary amine compounds, and alkali metal alkoxides can be used as catalysts. Examples of metals constituting the aforementioned organometallic salts include tin, zinc, and lead. Examples of alkali metals include sodium.

[0498] The reaction temperature between the prepolymer 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, there is a tendency to further improve reactivity. Furthermore, by setting the reaction temperature below the upper limit, there is a tendency to more effectively suppress side reactions.

[0499] To prevent the hydrophilic compound from remaining in an unreacted state, it is preferable to allow it to react completely with the prepolymer. Because it does not remain in an unreacted state, the water dispersibility of the hydrophilic polyisocyanate composition is improved.

[0500] <Characteristics of hydrophilic polyisocyanate compositions>

[0501] [Average number of functional groups in isocyanate groups]

[0502] In the hydrophilic polyisocyanate composition of this embodiment, the average number of isocyanate groups in the alicyclic polyisocyanate before hydrophilization (before modification with a hydrophilic compound), i.e., the alicyclic polyisocyanate used as a raw material, is preferably 2.5 or more and 6.0 or less, more preferably 2.7 or more and 5.8 or less, and even more preferably 2.9 or more and 5.5 or less.

[0503] By keeping the average number of functional groups within the above range, there is a tendency to further increase the hardness of the resin film.

[0504] The average number of functional groups can be determined using the methods described in the examples below.

[0505] [Weight-average molecular weight]

[0506] The weight-average molecular weight (Mw) of the hydrophilic polyisocyanate composition is preferably 900 or more and 20,000 or less, more preferably 1,200 or more and 18,000 or less, and even more preferably 1,300 or more and 17,000 or less.

[0507] By keeping the weight-average molecular weight within the above range, good water dispersibility is achieved, resulting in excellent hardness when the resin film is made.

[0508] The weight-average molecular weight can be determined using the methods described in the examples below.

[0509] <<Capped Polyisocyanate Compositions>>

[0510] The sixth embodiment of the end-capped polyisocyanate composition is formed by sealing at least a portion of the isocyanate groups in the above-mentioned hydrophilic polyisocyanate composition with an end-capping agent.

[0511] Preferably, all isocyanate groups in the hydrophilic polyisocyanate composition are sealed by a capping agent. The sealing of all isocyanate groups by the capping agent can be confirmed, for example, by Fourier transform infrared spectroscopy (FT-IR) based on the disappearance of absorption caused by isocyanates.

[0512] Furthermore, in the case where the end-capped polyisocyanate composition of this embodiment incorporates the aforementioned hydrophilic groups, and in addition to alicyclic polyisocyanates having isocyanurate groups (hereinafter sometimes referred to as "water-dispersible polyisocyanates"), alicyclic polyisocyanates without hydrophilic groups (hereinafter sometimes referred to as "non-alicyclic polyisocyanates"), and other polyisocyanates, it is preferable that the isocyanate groups of any polyisocyanate are sealed by the end-capping agent. The end-capping agents used to seal the isocyanate groups of water-dispersible polyisocyanates, non-alicyclic polyisocyanates, and other polyisocyanates can be the same or different, but are preferably the same.

[0513] The end-capped polyisocyanate composition of this embodiment is derived from the above-mentioned hydrophilic polyisocyanate composition. Therefore, it has good water dispersibility and excellent hardness and low-temperature curability when made into a resin film.

[0514] The components of the end-capped polyisocyanate composition of this embodiment are described in detail below. It should be noted that the hydrophilic polyisocyanate composition is as described above.

[0515] <End-capping agent>

[0516] There are no particular limitations on the end-capping agents; specifically, compounds with one active hydrogen atom in their molecule can be listed. Examples of such end-capping agents include alcohols, alkylphenols, phenols, active methylene compounds, thiols, acid amides, acid imides, imidazoles, ureas, oximes, amines, imines, pyrazoles, and triazoles. These end-capping agents can be used alone or in combination of two or more. More specific examples of end-capping agents are shown below.

[0517] As an alcohol compound, there is no particular limitation. Specifically, examples include methanol, ethanol, 2-propanol, n-butanol, sec-butanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, etc.

[0518] As alkylphenol compounds, there are no particular limitations. Specifically, examples include monoalkylphenols and dialkylphenols that have alkyl groups with four or more carbon atoms as substituents. Examples of monoalkylphenols include n-propylphenol, isopropylphenol, n-butylphenol, sec-butylphenol, tert-butylphenol, n-hexylphenol, 2-ethylhexylphenol, n-octylphenol, and n-nonylphenol. Examples of dialkylphenols include di-n-propylphenol, diisopropylphenol, isopropylcresol, di-n-butylphenol, di-tert-butylphenol, di-sec-butylphenol, di-n-octylphenol, di-2-ethylhexylphenol, and di-n-nonylphenol.

[0519] As phenolic compounds, there are no particular limitations. Specifically, examples include phenol, cresol, ethylphenol, styrenated phenol, and hydroxybenzoic acid esters.

[0520] As an active methylene compound, there is no particular limitation. Specifically, examples include dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, ethyl isobutyrylate, etc.

[0521] As a thiol compound, there is no particular limitation; specifically, examples include butyl thiol and dodecyl thiol.

[0522] As an acid amide compound, there are no particular limitations. Specifically, examples include acetanilide, acetamide, ε-caprolactam, δ-valerolactam, and γ-butyrolactam.

[0523] As an acid imide compound, there is no particular limitation; specifically, examples include succinimide and maleimide.

[0524] As imidazole compounds, there are no particular limitations; specifically, examples include imidazole, 2-methylimidazole, etc.

[0525] As urea compounds, there are no particular limitations; specifically, examples include urea, thiourea, and ethylene urea.

[0526] As oxime compounds, there are no particular limitations. Specifically, examples include formaldehyde oxime, acetaldehyde oxime, acetone oxime, methyl ethyl ketone oxime, cyclohexanone oxime, etc.

[0527] As amine compounds, there are no particular limitations. Specifically, examples include diphenylamine, aniline, carbazole, di-n-propylamine, diisopropylamine, isopropylethylamine, etc.

[0528] As an imine compound, there is no particular limitation; specifically, examples include ethyleneimine and polyethyleneimine.

[0529] As a pyrazole compound, there is no particular limitation; specifically, examples include pyrazole, 3-methylpyrazole, and 3,5-dimethylpyrazole.

[0530] As a triazole compound, there is no particular limitation; specifically, examples include 1,2,4-triazole, 1,2,3-triazole, etc.

[0531] From the viewpoints of ease of acquisition, viscosity of the resulting end-capped polyisocyanate composition, curing temperature and curing time, active methylene compounds, oxime compounds, amine compounds, pyrazole compounds or triazole compounds are preferred. From the viewpoint of particularly excellent curing properties of the resin film at low temperatures of around 80°C, diisopropyl malonate or di-tert-butyl malonate is particularly preferred.

[0532] <Method for manufacturing end-capped polyisocyanate compositions>

[0533] The end-capped polyisocyanate composition is not particularly limited, and is obtained by reacting, for example, the above-described hydrophilic polyisocyanate composition with the above-described end-capping agent.

[0534] The capping reaction between the hydrophilic polyisocyanate composition and the capping agent can be carried out regardless of the presence or absence of a solvent to obtain a capped polyisocyanate composition.

[0535] It should be noted that one type of capping agent can be used alone, or two or more types can be used in combination.

[0536] The amount of capping agent added is typically 80 mol% or more and 200 mol% or less relative to the total molar amount of isocyanate groups, preferably 90 mol% or more and 150 mol% or less, and more preferably 93 mol% or more and 130 mol% or less.

[0537] In addition, when using solvents, any solvent that is inert to isocyanate groups is acceptable.

[0538] When using a solvent, the content of solid components from the hydrophilic polyisocyanate composition and the capping agent is typically 10 parts by mass or more and 95 parts by mass or less relative to 100 parts by mass of the capping polyisocyanate composition, preferably 15 parts by mass or more and 80 parts by mass or less, and more preferably 20 parts by mass or more and 75 parts by mass or less.

[0539] When carrying out the end-capping reaction, organometallic salts of tin, zinc, lead, etc., tertiary amine compounds, and alkali metal alkoxides such as sodium can be used as catalysts.

[0540] The amount of catalyst added varies depending on factors such as the temperature of the end-capping reaction. Generally, it can be 0.05 parts by mass or more and 1.5 parts by mass or less relative to 100 parts by mass of polyisocyanate, preferably 0.05 parts by mass or more and 1.0 parts by mass or less.

[0541] The end-capping reaction can typically be carried out at temperatures above -20°C and below 150°C, preferably above 0°C and below 100°C, and more preferably above 10°C and below 90°C. By setting the end-capping reaction temperature above the aforementioned lower limit, the reaction rate can be further accelerated, and by setting it below the aforementioned upper limit, side reactions can be further suppressed.

[0542] After the end-capping reaction, neutralization can be achieved by adding acidic compounds.

[0543] As the aforementioned acidic compound, either inorganic or organic acids can be used. Examples of inorganic acids include hydrochloric acid, phosphorous acid, and phosphoric acid. Examples of organic acids include methanesulfonic acid, p-toluenesulfonic acid, dioctyl phthalate, and dibutyl phthalate.

[0544] Resin Compositions

[0545] The resin composition of the seventh embodiment includes a polyol, and the hydrophilic polyisocyanate composition of the fifth embodiment or the end-capped polyisocyanate composition of the sixth embodiment.

[0546] The resin composition of this embodiment, by including the above-mentioned hydrophilic polyisocyanate composition as a curing agent, exhibits excellent hardness when forming a resin film. Furthermore, the resin composition of this embodiment, by including the above-mentioned end-capped polyisocyanate composition, exhibits excellent hardness and curability at low temperatures (around 80°C) when forming a resin film.

[0547] The composition of the resin composition of this embodiment will be described in detail below. It should be noted that the hydrophilic polyisocyanate composition and the capped polyisocyanate composition are described above.

[0548] <Polyols>

[0549] Examples of polyols include polyester polyols, polyether polyols, acrylic polyols, polyolefin polyols, fluorinated polyols, polycarbonate polyols, and polyurethane polyols. These polyols can be a single type or a combination of two or more.

[0550] Among them, polyester polyols, acrylic polyols, or mixtures thereof are preferred as polyols.

[0551] [Polyester polyols]

[0552] Polyester polyols can be obtained, for example, by condensing one or more dicarboxylic acids with one or more polyols.

[0553] Examples of the aforementioned dicarboxylic acids include succinic acid, adipic acid, dimer acids, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, and 1,4-cyclohexanedicarboxylic acid.

[0554] Examples of the aforementioned polyols include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, trimethylolpropane, glycerol, pentaerythritol, 2-hydroxymethylpropanediol, and ethoxylated trimethylolpropane.

[0555] Alternatively, polycaprolactones, such as those obtained by ring-opening polymerization of lactones like ε-caprolactone using polyols, can also be used as polyester polyols.

[0556] [Polyether polyols]

[0557] As a type of polyether polyol, there are no particular limitations, and examples such as the polyether polyols shown in (1) to (3) below can be listed.

[0558] (1) Polyether polyols obtained by random addition or block addition of epoxides alone or in mixtures to polyhydroxy compounds alone or in mixtures using a catalyst.

[0559] Examples of catalysts mentioned above include hydroxides (lithium, sodium, potassium, etc.), strongly basic catalysts (alkoxides, alkylamines, etc.), and complex metal cyanide compounds (metal porphyrins, zinc hexacyanocobaltate complexes, etc.).

[0560] Examples of the aforementioned epoxides include ethylene oxide, propylene oxide, butane oxide, cyclohexane oxide, and phenylene oxide.

[0561] (2) Polyether polyols obtained by reacting epoxides with polyamine compounds.

[0562] Examples of the aforementioned polyamine compounds include, for example, ethylenediamines.

[0563] As for the aforementioned epoxides, examples of epoxides that are the same as those exemplified in (1) can be listed.

[0564] (3) The so-called polymer polyol obtained by polymerizing acrylamide and the like using polyether polyols obtained by (1) or (2) as a medium.

[0565] Examples of the aforementioned polyhydroxy compounds include, for example, the polyhydroxy compounds shown in (i) to (vi) below.

[0566] (i) diglycerides, di(trimethylolpropane), pentaerythritol, dipentaerythritol, etc.

[0567] (ii) Sugar alcohol compounds such as erythritol, D-threitol, L-arabinitol, ribitol, xylitol, sorbitol, mannitol, galactitol, and rhamnitol.

[0568] (iii) Monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbose, rhamnose, fucose, and deoxyribose.

[0569] (iv) Disaccharides such as trehalose, sucrose, maltose, cellulosic disaccharide, gentiobiose, lactose, and melibiose.

[0570] (v) Trisaccharides such as melitriose, gentiotriose, and pinotriose.

[0571] (vi) Stachyose and other four sugars.

[0572] [Acrylic polyols]

[0573] As an acrylic polyol, there are no particular limitations, examples of acrylic polyols obtained by copolymerizing, for instance, a monomer having hydroxyl groups and containing an olefinic unsaturated bond, alone or in mixture, with other monomers containing olefinic unsaturated bonds, alone or in mixture, that can copolymerize with it.

[0574] The monomers containing hydroxyl groups and olefinic unsaturated bonds mentioned above are not particularly limited, and examples include hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate. They can be used alone or in combination of two or more. Among them, hydroxyethyl acrylate or hydroxyethyl methacrylate are preferred.

[0575] Other monomers containing olefinic unsaturated bonds that can copolymerize with the above monomers include, for example, the monomers shown in (1) to (6) below. They can be used alone or in combination of two or more.

[0576] (1) Acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, benzyl acrylate, phenyl acrylate, etc.; 2-methoxyethyl acrylate, ethoxyethyl acrylate, methoxy polyethylene glycol acrylate.

[0577] (2) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, benzyl methacrylate, phenyl methacrylate and other methacrylates.

[0578] (3) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid.

[0579] (4) Acrylamide, methacrylamide, N,N-methylenebisacrylamide, diacetone acrylamide, diacetone methacrylamide, maleic acid amide, maleimide and other unsaturated amides.

[0580] (5) Vinyl monomers such as glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, and dibutyl fumarate.

[0581] (6) Vinyl monomers with hydrolyzable silanes, such as vinyltrimethoxysilane, vinylmethyldimethoxysilane, and γ-(meth)acryloyloxypropyltrimethoxysilane.

[0582] [Polyolefin polyols]

[0583] As a polyolefin polyol, there are no particular limitations, and examples include polybutadiene, hydrogenated polybutadiene, polyisoprene, and hydrogenated polyisoprene, which have more than two hydroxyl groups.

[0584] The number of hydroxyl groups per molecule of the polyol (hereinafter sometimes referred to as the "average number of hydroxyl groups") is preferably 2 or more. By making the average number of hydroxyl groups of the polyol 2 or more, there is a tendency to further suppress the decrease in the crosslinking density of the coating film obtained by curing the single-component coating composition of this embodiment.

[0585] [Fluoropolyols]

[0586] In this specification, "fluorinated polyol" refers to a polyol containing fluorine in its molecule. Specifically, examples of fluorinated polyols include copolymers of fluoroolefins, cyclovinyl ethers, hydroxyalkyl vinyl ethers, and vinyl monocarboxylate disclosed in Japanese Patent Application Publication No. 57-34107 (Reference 1) and Japanese Patent Application Publication No. 61-275311 (Reference 2).

[0587] [Polycarbonate polyols]

[0588] As a type of polycarbonate polyol, there is no particular limitation, and examples such as the polycarbonate polyols shown in (1) to (4) below can be listed.

[0589] (1) Dialkyl carbonates such as dimethyl carbonate;

[0590] (2) Ethylene carbonate and other alkylene carbonates;

[0591] (3) Diphenyl carbonate and other diaryl carbonate esters;

[0592] (4) Products obtained by polycondensation of the low molecular weight carbonate compounds (1) to (3) mentioned above.

[0593] [Polyurethane Polyols]

[0594] As a polyurethane polyol, there are no particular limitations; it can be obtained, for example, by reacting a carboxyl-free polyol with an isocyanate component using conventional methods.

[0595] Examples of carboxyl-free polyols include, for example, low molecular weight polyols such as ethylene glycol and propylene glycol. Examples of high molecular weight polyols include, for example, acrylic polyols, polyester polyols, and polyether polyols.

[0596] [Hydroxyl value of polyols]

[0597] The hydroxyl value per unit resin of polyol is not particularly limited, but is preferably 10 mg KOH / g or more and 300 mg KOH / g or less.

[0598] By setting the hydroxyl value of the unit resin to the lower limit or above, there is a tendency to suppress the reduction of crosslinking density and achieve the target properties more fully. By setting the hydroxyl value of the unit resin to the upper limit or below, there is a tendency to suppress the excessive increase of crosslinking density and further improve the mechanical properties of the coating film obtained by curing the single-component coating composition of this embodiment.

[0599] It should be noted that the hydroxyl value of polyols can be determined according to JIS K1557.

[0600] <Other Additives>

[0601] The resin composition of this embodiment may further contain other additives.

[0602] Other additives include curing agents, curing catalysts, solvents, pigments (extender pigments, coloring pigments, metallic pigments, etc.) that can react with the cross-linking functional groups in polyols, ultraviolet absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents that inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, film-forming aids, etc.

[0603] Examples of curing agents mentioned above include melamine resin, urea resin, epoxy-containing compounds or resins, carboxyl-containing compounds or resins, acid anhydrides, alkoxysilyl-containing compounds or resins, and hydrazide compounds.

[0604] The aforementioned curing catalyst can be either a basic compound or a Lewis acid compound.

[0605] Examples of the aforementioned basic compounds include, for example, metal hydroxides, metal alkoxides, metal carboxylates, metal acetylacetonates, hydroxides of onium salts, onium carboxylates, halides of onium salts, metal salts of active methylene compounds, onium salts of active methylene compounds, aminosilanes, amines, and phosphines. Among the aforementioned onium salts, ammonium salts, phosphonium salts, or sulfonium salts are suitable.

[0606] Examples of Lewis acidic compounds include organotin compounds, organozinc compounds, organotitanium compounds, and organozirconium compounds.

[0607] As the aforementioned solvent, solvents identical to those exemplified in the above-described capped polyisocyanate compositions can be listed.

[0608] In addition, known substances can be appropriately selected and used as pigments (extender pigments, coloring pigments, metallic pigments, etc.), ultraviolet absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents that inhibit coloring during baking processes, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, and film-forming aids.

[0609] <Method for manufacturing resin composition>

[0610] The resin composition of this embodiment can be used in both solvent-based and aqueous-based matrices. When the resin composition contains the above-described end-capped polyisocyanate composition, a resin composition exhibiting excellent low-temperature curing properties below 80°C when forming a resin film is currently unknown; therefore, it is suitable for use in the form of an aqueous-based resin composition.

[0611] In manufacturing an aqueous resin composition (aqueous resin composition), firstly, additives such as curing agents, curing catalysts, solvents, pigments (extender pigments, coloring pigments, metallic pigments, etc.), ultraviolet absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents that inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, and film-forming aids are added to a polyol or its aqueous dispersion as a curing agent, and water and solvents are further added as needed to adjust the viscosity. Then, by forcibly stirring using a mixer, an aqueous resin composition (aqueous resin composition) can be obtained.

[0612] When manufacturing a solvent-based resin composition, firstly, additives such as curing agents, curing catalysts, solvents, pigments (extender pigments, coloring pigments, metallic pigments, etc.), UV absorbers, light stabilizers, free radical stabilizers, anti-yellowing agents to inhibit coloring during the baking process, coating conditioners, flow conditioners, pigment dispersants, defoamers, thickeners, and film-forming aids are added to a polyol or its solvent dilution as needed. Next, the aforementioned hydrophilic polyisocyanate composition or the aforementioned end-capped polyisocyanate composition is added as a curing agent, and solvent is further added as needed to adjust the viscosity. Then, by stirring using a stirring device such as a manual stirrer or a mixer, a solvent-based resin composition can be obtained.

[0613] <<Resin Film>>

[0614] The resin film of the eighth embodiment is formed by curing the resin composition of the seventh embodiment described above. The resin film of this embodiment exhibits excellent hardness by using the resin composition comprising the hydrophilic polyisocyanate composition of the fifth embodiment described above. Furthermore, when using the resin composition comprising the end-capped polyisocyanate composition of the sixth embodiment described above, the curing properties at low temperatures of around 80°C are even better.

[0615] The resin film of this embodiment can be obtained by coating the above-mentioned resin composition onto a substrate using known methods such as roller coating, curtain coating, spraying, bell gun coating, and electrostatic coating, and then heating it to cure it.

[0616] From the viewpoint of energy saving and heat resistance of the substrate, the heating temperature is preferably about 60°C or higher and about 120°C or lower, more preferably about 65°C or higher and about 110°C or lower, and even more preferably about 70°C or higher and about 100°C or lower.

[0617] From the viewpoint of energy saving and heat resistance of the substrate, the heating time is preferably about 1 minute or more and about 60 minutes or less, more preferably about 2 minutes or more and about 40 minutes or less.

[0618] As a substrate, there are no particular limitations, but examples include the outer panels of car bodies such as cars, trucks, motorcycles, and buses; automotive parts such as bumpers; the outer panels of household electrical products such as mobile phones and audio equipment; and various films.

[0619] There are no particular limitations on the material of the substrate. Examples include metal materials such as iron, aluminum, brass, copper, tinplate, stainless steel, galvanized steel, and galvanized alloy steel (Zn-Al, Zn-Ni, Zn-Fe, etc.); resins such as polyethylene resin, polypropylene resin, acrylonitrile-butadiene-styrene (ABS) resin, polyamide resin, acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, and epoxy resin; various FRP (fiber-reinforced plastic) and other plastic materials; inorganic materials such as glass, cement, and concrete; wood; and fiber materials such as paper and cloth.

[0620] The substrate can be a substrate obtained by performing surface treatments such as phosphate treatment, chromate treatment, or composite oxide treatment on the surface of the aforementioned metal material or the metal surface of a vehicle body or the like formed from the aforementioned metal material, and then a coating film can be formed on it. As a substrate with a coating film, it can be a product obtained by performing surface treatment as needed and forming a primer coating film thereon, for example, a vehicle body with a primer coating film formed by electrodeposition of a coating. The substrate can also be a substrate obtained by performing a desired surface treatment on the surface of the aforementioned plastic material or the plastic surface of an automotive part or the like formed from the aforementioned plastic material. Furthermore, the substrate can combine plastic and metal materials.

[0621] Example

[0622] The present embodiment will be described in more detail below based on the embodiments and comparative examples, but the present embodiment is not limited to the following embodiments at all.

[0623] <<Examples 1-1 to 1-18 and Comparative Examples 1-1 to 1-6>>

[0624] <Experimental Projects>

[0625] For the capped polyisocyanate compositions obtained in the examples and comparative examples, various physical properties were determined and evaluated according to the methods shown below.

[0626] [Physical Properties 1-1]

[0627] (Isocyanate group (NCO) content)

[0628] To determine the NCO content of polyisocyanates, the polyisocyanates before end-capping with an end-capping agent were used as the test sample.

[0629] First, accurately weigh 2 g but less than 3 g (Wg) of the test sample into a flask. Next, add 20 mL of toluene to dissolve the test sample. Then, add 20 mL of a toluene solution containing 2 equivalents of di-n-butylamine, mix, and let stand at room temperature for 15 minutes. Next, add 70 mL of isopropanol and mix. Then, titrate this liquid with 1 equivalent of hydrochloric acid solution (factor F) to an indicator. Set the resulting titration value as V2 mL. Next, perform the same operation without the polyisocyanate sample, and set the resulting titration value as V1 mL. Then, calculate the isocyanate group (NCO) content of the polyisocyanate (Isocyanate group (NCO) content) (mass %) using the following formula.

[0630] Isocyanate group (NCO) content (mass%) = (V1-V2)×F×42 / (W×1000)×100

[0631] [Physical Properties 1-2]

[0632] (Number average molecular weight)

[0633] The number-average molecular weight is the number-average molecular weight of polystyrene as a reference, determined by gel permeation chromatography (GPC) using the apparatus described below. To determine the number-average molecular weight of polyisocyanates, the polyisocyanate before end-capping with a capping agent is used as the test sample. The test conditions are shown below.

[0634] (Measurement conditions)

[0635] Device: Tosoh Corporation, HLC-802A

[0636] Column: Tosoh Corporation, G1000HXL x 1 piece

[0637] G2000HXL × 1 piece

[0638] G3000HXL × 1 piece

[0639] Support: Tetrahydrofuran

[0640] Test method: Differential refractometer

[0641] [Physical Properties 1-3]

[0642] (Average number of isocyanate functional groups)

[0643] The average number of isocyanate functional groups (average NCO number) of the polyisocyanate is calculated using the following formula. It should be noted that in the formula, "Mn" is the number-average molecular weight of the polyisocyanate before end-capping with the end-capping agent in the end-capped polyisocyanate composition, using the value obtained in "Physical Property 1-2" above. "NCO content" is the isocyanate group content of the polyisocyanate measured before end-capping with the end-capping agent in the end-capped polyisocyanate composition, using the value calculated in "Physical Property 1-1" above.

[0644] Average number of isocyanate functional groups = (Mn × NCO content × 0.01) / 42

[0645] [Physical Properties 1-4]

[0646] (Amount of solids in the capped polyisocyanate composition)

[0647] The solid content of the capped polyisocyanate composition was determined as follows.

[0648] First, an aluminum dish with a bottom diameter of 38 mm was accurately weighed. Next, approximately 1 g of the end-capped polyisocyanate composition prepared in the examples and comparative examples was accurately weighed on the aluminum dish (W1). Then, the end-capped polyisocyanate composition was adjusted to a uniform thickness. Next, the end-capped polyisocyanate composition, while still supported on the aluminum dish, was kept in an oven at 105°C for 1 hour. Next, after the aluminum dish reached room temperature, the remaining end-capped polyisocyanate composition on the aluminum dish was accurately weighed (W2). Then, the amount of solids (mass%) of the end-capped polyisocyanate composition was calculated using the following formula.

[0649] Solid content of the capped polyisocyanate composition [mass %] = W2 / W1 × 100

[0650] [Physical Properties 1-5]

[0651] (Surface tension of the dispersant at 25°C)

[0652] The dispersants used in the examples and comparative examples were diluted with water to prepare an aqueous dispersant solution containing water and 0.1% by mass of the aforementioned anionic dispersant relative to the total mass of the aqueous solution. Then, the surface tension at 25°C was determined using the Wilhelmy method with this aqueous dispersant solution.

[0653] [Preparation of the resin composition]

[0654] An acrylic polyol (Setaqua 6515, a registered trademark manufactured by Nuplex, with OH (%) (on solids) = 3.3, acid value (mgKOH / g) = 9.9, and resin content of 45%) was mixed with various end-capped polyisocyanate compositions in such a way that the molar ratio of isocyanate groups to hydroxyl groups (isocyanate groups / hydroxyl groups) reached 1. The mixture was further mixed with deionized water, and the resin composition was prepared with a solid content of 40% by mass.

[0655] [Evaluation 1-1] Storage stability

[0656] For 20g of the obtained resin composition, the initial viscosity and the viscosity after storage at 40°C for 10 days in a 20mL glass bottle were measured (viscometer: RE-85R manufactured by Toki Sangyo Co., Ltd.). The ratio of the stored viscosity to the initial viscosity was calculated. It should be noted that a stored viscosity ratio of 2.5 or less, indicating no gelation or precipitation, is considered good. A stored viscosity ratio greater than 1, with values ​​close to 1 and less than 1, is considered particularly good.

[0657] [Evaluation 1-2] Low-temperature curing properties

[0658] The obtained resin composition was coated onto a polypropylene (PP) plate to achieve a dry film thickness of 40 μm, and then dried at 80°C for 30 minutes to obtain a resin film. The resin film was then stored at room temperature (23°C) for one week, and the gelation rate was determined. The gelation rate was expressed as a percentage (mass%) of the undissolved portion of the resin film after immersion in acetone at 23°C for 24 hours, divided by the mass before immersion. It should be noted that a gelation rate of 80% or higher is considered good.

[0659] Synthesis of Polyisocyanates

[0660] [Synthesis Example 1-1]

[0661] (Synthesis of polyisocyanate P-1)

[0662] Under a nitrogen gas flow, 100 parts by mass of HDI and 5.1 parts by mass of a polyester polyol derived from triols and ε-caprolactone (manufactured by Daicel Chemicals, "PLACCEL 303" (trade name)) were added to a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser. The temperature inside the reactor was maintained at 90°C for 1 hour with stirring to carry out the carbamate reaction. Subsequently, the temperature inside the reactor was maintained at 60°C, and tetramethyldecanoate ammonium, an isocyanurate esterification catalyst, was added. Phosphoric acid was added when the yield reached 51% by mass to stop the reaction. The reaction solution was filtered, and unreacted HDI was removed using a thin-film evaporator to obtain an isocyanurate-type polyisocyanate (hereinafter sometimes referred to as "polyisocyanate P-1"). The obtained polyisocyanate P-1 had an NCO content of 18.8% by mass, a number-average molecular weight of 1130, and an average isocyanate base of 5.1. Furthermore, GPC analysis and... 1 H-NMR analysis confirmed the presence of isocyanurate trimer.

[0663] [Synthesis example 1-2]

[0664] (Synthesis of polyisocyanate P-2)

[0665] Under a nitrogen gas flow, 80 parts by mass of HDI, 20 parts by mass of IPDI, and 3.4 parts by mass of trimethylolpropane (triol) were added to a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser. The temperature inside the reactor was maintained at 90°C for 1 hour with stirring to carry out the carbamate reaction. Subsequently, the temperature inside the reactor was maintained at 77°C, and 0.012 parts by mass of tetramethyldecanoate ammonium (a catalyst for isocyanurate esterification) was added. Phosphoric acid was added when the yield reached 45% by mass to stop the reaction. The reaction solution was filtered, and unreacted HDI and IPDI were removed using a thin-film evaporator to obtain isocyanurate-type polyisocyanate (hereinafter sometimes referred to as "polyisocyanate P-2"). The obtained polyisocyanate P-2 had an NCO content of 19.1% by mass, a number-average molecular weight of 1210, and an average isocyanate base number of 5.5. Furthermore, GPC analysis and... 1 H-NMR analysis confirmed the presence of isocyanurate trimer.

[0666] <Preparation of capped polyisocyanate compositions>

[0667] [Example 1-1]

[0668] (Preparation of the capped polyisocyanate composition BL-a1)

[0669] Under a nitrogen atmosphere, a mixture of 100 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 1-1, 24 parts by mass of methoxy polyethylene glycol (MPG-081, ethylene oxide repeating unit: 15, manufactured by Nippon Emulsifier Co., Ltd., which is 8 mol% relative to 100 mol% of isocyanate groups), 0.01 parts by mass of 2-ethylhexyl phosphate (JP-508T, manufactured by Jōhoku Chemical Co., Ltd., manufactured by Jōhoku Chemical Co., Ltd.), and 67 parts by mass of dipropylene glycol dimethyl ether (DPDM) was introduced into a four-necked flask equipped with a thermometer, stirring blade, and reflux condenser, and the reaction was carried out at 115°C for 2 hours. The reaction solution was cooled to 40°C, and di-tert-butyl malonate was added as a capping agent in a manner that reaches 1.1 mol equivalents relative to the molar amount of isocyanate groups in the reactants. Then, 1.0 part by mass of a methanol solution containing sodium methoxide (28 mol%) was added, and the mixture was stirred. The inner bath was maintained at 50°C and stirred for more than 6 hours. Infrared spectroscopy confirmed the disappearance of the characteristic absorption of the isocyanate groups. DPDM was added at a solid content of 60% by mass and stirred, then cooled to below 40°C. Subsequently, polyoxyethylene polycyclic phenyl ether ammonium sulfate (polyoxyethylene (oxyethylene (repetition number of ethylene n = 10-15) alkyl (carbon number of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether ammonium sulfate) as a dispersant was added to the reaction solution at a ratio of 1.5 parts by mass relative to 100 parts by mass of the end-capped polyisocyanate solid content (surface tension 40.3 mM / m at 25°C)). The mixture was stirred for another 30 minutes to obtain the end-capped polyisocyanate composition BL-a1.

[0670] [Examples 1-2 to 1-11 and Comparative Examples 1-1 to 1-6]

[0671] (Preparation of capped polyisocyanate compositions BL-a2~BL-a11 and BL-b1~BL-b6)

[0672] Except for the types of capping agents, the amount of hydrophilic compounds, and the types and amounts of dispersants listed in Tables 1, 2, and 4, the capped polyisocyanate compositions BL-a2 to BL-a11 and BL-b1 to BL-b6 were manufactured using the same method as in Examples 1-1.

[0673] [Examples 1-12]

[0674] (Preparation of the capped polyisocyanate composition BL-a12)

[0675] Under a nitrogen gas flow, in a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser, di-tert-butyl malonate was added to polyisocyanate P-1 obtained by Synthesis Example 1-1 in such a way that the molar amount of isocyanate groups relative to the polyisocyanate reached 1.1 molar equivalents, and DPDM was added in such a way that the solid content reached 60% by mass. Then, 1.0 part by mass of a methanol solution containing sodium methoxide (28% by mass) was added. The inner bath was maintained at 50°C and stirred for more than 6 hours. The characteristic absorption of the isocyanate groups was confirmed to disappear by infrared spectroscopy. Next, the reaction solution was cooled to below 40°C, and polyoxyethylene alkyl ether ammonium sulfate (the compound shown in general formula (II-1) below; sometimes referred to as "compound (II-1)") (with a surface tension of 30.7 mN / m at 25°C) was added at room temperature to obtain the end-capped polyisocyanate composition BL-a12.

[0676] R 21 -O-(CH2CH2O) 30 -SO3NH4 (II-1)

[0677] In general formula (II-1), R 21 It is a tridecyl group.

[0678] [Examples 1-13 to 1-14]

[0679] (Preparation of capped polyisocyanate compositions BL-a13~BL-a14)

[0680] Except for the types of capping agents, the amount of hydrophilic compounds, and the types and amounts of dispersants listed in Table 3, the capped polyisocyanate compositions BL-a13 to BL-a14 were manufactured using the same method as in Examples 1-12.

[0681] [Examples 1-15 to 1-16]

[0682] (Preparation of capped polyisocyanate compositions BL-a15~BL-a16)

[0683] Regarding the two capping agents B-1 and B-2, in Examples 1-15, the mixture of B-1 and B-2 was used in a molar ratio of B-1:B-2 = 50 mol%: 50 mol%, and in Examples 1-16, the mixture of B-1:B-2 was used in a molar ratio of B-1:B-2 = 20 mol%: 80 mol%. The mixing amounts of the hydrophilic compounds, the types and amounts of the dispersants are set as described in Table 3. Otherwise, the capped polyisocyanate compositions BL-a15 to BL-a16 were manufactured using the same method as in Examples 1-1.

[0684] [Examples 1-17 to 1-18]

[0685] (Preparation of capped polyisocyanate compositions BL-a17 to BL-a18)

[0686] Using polyisocyanate P-2, and regarding the two capping agents B-1 and B-2, for Examples 1-17, the mixing amount of B-1 and B-2 was such that the molar ratio of B-1:B-2 was 50 mol%:50 mol%, and for Examples 1-18, the mixing amount of B-1:B-2 was 35 mol%:65 mol%. The mixing amount of the hydrophilic compound and the type and mixing amount of the dispersant are set as described in Table 3. Otherwise, the capped polyisocyanate compositions BL-a17 to BL-a18 were prepared using the same method as in Examples 1-1.

[0687] Furthermore, various evaluations were performed using the methods described above on the capped polyisocyanate compositions obtained in the Examples and Comparative Examples. The results are shown in Tables 1 to 4 below.

[0688] It should be noted that the types of capping agents and dispersants in Tables 1 to 4 are as follows.

[0689] (End-capping agent)

[0690] B-1: Di-tert-butyl malonate

[0691] B-2: Diisopropyl malonate

[0692] (Dispersant)

[0693] D-1: Ammonium sulfate of polyoxyethylene polycyclic phenyl ether (polyoxyethylene (repetition number of oxyethylene n = 10-15) alkyl (carbon number of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether ammonium sulfate) (surface tension at 25°C is 40.3 mN / m)

[0694] D-2: Sodium sulfate of polyoxyethylene polycyclic phenyl ether (sodium sulfate of polyoxyethylene (repeating number of oxyethylene n = 10-15) alkyl (carbon number of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether) (surface tension at 25°C is 41.5 mN / m)

[0695] D-3: Polyoxyethylene alkyl ether ammonium sulfate (a compound represented by the general formula (II-2) below; sometimes referred to as "compound (II-2)" hereafter) (surface tension at 25°C is 40.4 mN / m)

[0696] R 22 -O-(CH2CH2O)8-SO3NH4 (II-2)

[0697] In general formula (II-2), R 22It is an alkyl group with 12 or 13 carbon atoms. Compound (II-2) is R 22 Compounds of alkyl groups having 12 carbon atoms and R 22 A mixture of compounds consisting of alkyl groups having 13 carbon atoms.

[0698] D-4: Polyoxyalkylene alkyl ether phosphate (a compound represented by the general formula (II-3) below; sometimes referred to as "compound (II-3)") (surface tension at 25°C is 30.7 mN / m)

[0699] R 23 -O-(CH2CH2O)2-OPOOHONa (II-3)

[0700] In general formula (II-3), R 23 It is 2-ethylhexyl.

[0701] D-5: Polyoxyethylene alkyl ether sulfate salt (the compound shown in general formula (II-4) below; sometimes referred to as "compound (II-4)" below) (surface tension at 25°C is 52.1 mN / m)

[0702] R 24 -O-(CH2CH2O) 60 -SO3Na (II-4)

[0703] In general formula (II-4), R 24 It is an alkyl group with 12 or 13 carbon atoms. Compound (II-4) is R 24 Compounds of alkyl groups having 12 carbon atoms and R 24 A mixture of compounds consisting of alkyl groups having 13 carbon atoms.

[0704] D-6: Polyoxyethylene alkyl ether ammonium sulfate (compound (II-1) above) (surface tension at 25°C is 38.8 mN / m)

[0705] D-7: Sodium polyoxyethylene alkyl ether sulfate (the compound shown in general formula (II-5) below; sometimes referred to as "compound (II-5)" below) (surface tension at 25°C is 45.9 mN / m)

[0706] R 25 -O-(CH2CH2O) 20 -SO3Na (II-5)

[0707] In general formula (II-5), R 25 It is an alkyl group with 12 or 13 carbon atoms. Compound (II-5) is R 25 Compounds of alkyl groups having 12 carbon atoms and R 25A mixture of compounds consisting of alkyl groups having 13 carbon atoms.

[0708] Furthermore, in Table 4, regarding storage stability, the ratio of viscosity after storage to initial viscosity could not be calculated due to gelation or precipitation.

[0709] [Table 1]

[0710]

[0711] [Table 2]

[0712]

[0713] [Table 3]

[0714]

[0715] [Table 4]

[0716]

[0717] According to Tables 1-4, the capped polyisocyanate compositions BL-a1 to BL-a18 (Examples 1-1 to 1-18) containing a dispersant with a surface tension of 38.8 mN / m or more and 45.9 mN / m or less at 25°C exhibit good storage stability when made into resin compositions and good low-temperature curing properties when made into resin films.

[0718] Furthermore, in the capped polyisocyanate compositions BL-a1 to BL-a9 (Examples 1-1 to 1-9) with different amounts of hydrophilic compounds, the following trend was observed: the lower the amount of hydrophilic compound, the better the storage stability when the resin composition was prepared.

[0719] On the other hand, the capped polyisocyanate compositions BL-b1 to BL-b6 (Comparative Examples 1-1 to 1-6) containing a dispersant with a surface tension of 30.7 mN / m or 52.1 mN / m at 25°C or without a dispersant, gelled or precipitated when the resin compositions were prepared, resulting in poor storage stability.

[0720] Examples 2-1 to 2-42 and Comparative Examples 2-1 to 2-12

[0721] <Experimental Projects>

[0722] For the polyols, various physical properties were determined according to the methods shown below. It should be noted that the solid content of the capped polyisocyanate compositions and the surface tension of the dispersant at 25°C were determined using the same methods as in "Examples 1-1 to 1-18 and Comparative Examples 1-1 to 1-6" above. The resin compositions obtained in the examples and comparative examples were evaluated according to the methods shown below. It should be noted that storage stability and low-temperature curability were evaluated using the same methods as in "Examples 1-1 to 1-18 and Comparative Examples 1-1 to 1-6" above.

[0723] [Physical Properties 2-1]

[0724] (Glass transition temperature)

[0725] Regarding the glass transition temperature of polyols, for substances obtained by vacuum drying after removing organic solvents and water from a polyol solution under reduced pressure, the value obtained using a differential scanning calorimeter (DSC) at a heating rate of 5°C / min is used as the glass transition temperature.

[0726] [Physical Properties 2-2]

[0727] (weight-average molecular weight)

[0728] The weight-average molecular weight of the polyols was determined by GPC using the apparatus described below, based on polystyrene. The polyols used in the examples and comparative examples were used as test samples. The test conditions are shown below.

[0729] (Measurement conditions)

[0730] Device: Tosoh Corporation, HLC-802A

[0731] Column: Tosoh Corporation, G1000HXL x 1 piece

[0732] G2000HXL × 1 piece

[0733] G3000HXL × 1 piece

[0734] Support: Tetrahydrofuran

[0735] Test method: Differential refractometer

[0736] [Physical Properties 2-3]

[0737] (hydroxyl value)

[0738] The hydroxyl value of a polyol is calculated using potentiometric titration. Furthermore, the hydroxyl value is relative to the solid component of the polyol.

[0739] [Rating 2-1]

[0740] (Tensile strength)

[0741] The obtained resin composition was coated onto a polypropylene (PP) sheet to achieve a dry film thickness of 40 μm, and then dried at 80°C for 30 minutes to obtain a resin film. The obtained resin film was cut into pieces 10 mm wide and 40 mm long, and the fixtures were set with a distance of 20 mm between them. A tensile test was performed at a speed of 20 mm / min. The maximum point stress at this time was taken as the maximum stress value, and the tensile strength was calculated.

[0742] Synthesis of Polyisocyanates

[0743] [Synthetic Example 2-1] Synthesis of Polyisocyanate P-1

[0744] Using the same method as in the above synthetic example "1-1", an isocyanurate-type polyisocyanate (hereinafter sometimes referred to as "polyisocyanate P-1") was obtained.

[0745] <Preparation of capped polyisocyanate compositions>

[0746] [Example 2-1]

[0747] (Preparation of the capped polyisocyanate composition BL-a19)

[0748] Under a nitrogen atmosphere, in a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser, 100 parts by mass of polyisocyanate P-1 obtained in Synthesis Example 2-1, 21 parts by mass of methoxy polyethylene glycol (MPG-081, ethylene oxide repeating unit: 15, manufactured by Nippon Emulsifier Co., Ltd.) (7 mol% relative to 100 mol% of isocyanate groups), 0.01 parts by mass of 2-ethylhexyl phosphate (JP-508T, manufactured by Johoku Chemical Co., Ltd.), and 67 parts by mass of dipropylene glycol dimethyl ether (DPDM) were mixed and reacted at 115°C for 2 hours. The reaction solution was cooled to 40°C, and di-tert-butyl malonate was added as a capping agent in a manner that achieved a molar equivalent relative to the isocyanate groups in the reactants of 1.1 mol equivalents. Then, 1.0 part by mass of a methanol solution containing sodium methoxide (28 mol%) was added, and the mixture was stirred. The inner bath was maintained at 50°C and stirred for at least 6 hours. Infrared spectroscopy confirmed the disappearance of the characteristic absorption of the isocyanate groups. DPDM was added at a solid content of 60% by mass and stirred, then cooled to below 40°C. Subsequently, polyoxyethylene polycyclic phenyl ether ammonium sulfate (polyoxyethylene (oxyethylene (repetition number of ethylene n = 10-15) alkyl (carbon number of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether ammonium sulfate) as a dispersant was added to the reaction solution at a ratio of 1.3 parts by mass relative to 100 parts by mass of the end-capped polyisocyanate (surface tension at 25°C is 40.3 mM / m)). The mixture was stirred for another 30 minutes to obtain the end-capped polyisocyanate composition BL-a19.

[0749] [Examples 2-2 to 2-11, 2-15 to 2-17 and Comparative Examples 2-1 to 2-6]

[0750] (Preparation of capped polyisocyanate compositions BL-a20~BL-a29, BL-a33~BL-a35 and BL-b7~BL-b12)

[0751] Except for the types of capping agents, the amount of hydrophilic compounds, and the types and amounts of dispersants listed in Tables 5-8, the capped polyisocyanate compositions BL-a20-BL-a29, BL-a33-BL-a35, and BL-b7-BL-b12 were manufactured using the same method as in Example 2-1.

[0752] [Example 2-12]

[0753] (Preparation of the capped polyisocyanate composition BL-a30)

[0754] Under a nitrogen atmosphere, in a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser, di-tert-butyl malonate was added to polyisocyanate P-1 obtained by Synthesis Example 2-1 in such a way that the molar amount of isocyanate groups relative to the polyisocyanate was 1.1 molar equivalents, DPDM was added in such a way that the solid content was 60% by mass, and then 1.0 part by mass of a methanol solution containing sodium methoxide (28% by mass) was added. The inner bath was maintained at 50°C and stirred for more than 6 hours. The characteristic absorption of the isocyanate groups was confirmed to have disappeared by infrared spectroscopy. Then, the reaction solution was cooled to below 40°C, and then polyoxyethylene alkyl ether ammonium sulfate (compound (II-1)) (with a surface tension of 30.7 mN / m at 25°C) was added at room temperature to obtain the end-capped polyisocyanate composition BL-a30.

[0755] [Examples 2-13 to 2-14]

[0756] (Preparation of capped polyisocyanate compositions BL-a31 to BL-a32)

[0757] Except for the types of capping agents, the amount of hydrophilic compounds, and the types and amounts of dispersants listed in Table 6, the capped polyisocyanate compositions BL-a31 to BL-a32 were prepared using the same method as in Examples 2-12.

[0758] It should be noted that the types of capping agents and dispersants in Tables 5 to 8 are the same as those in "Examples 1-1 to 1-18 and Comparative Examples 1-1 to 1-6" above.

[0759] [Table 5]

[0760]

[0761] [Table 6]

[0762]

[0763] [Table 7]

[0764]

[0765] [Table 8]

[0766]

[0767] <Manufacturing of Polyols>

[0768] [Manufacturing Example 2-1]

[0769] (Manufacturing of polyol OHP1)

[0770] Propylene glycol monomethyl ether (33 parts by mass) was added to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen inlet. The flask was heated to 110°C under nitrogen purging. After reaching 110°C, nitrogen purging was stopped, and a mixture containing 25.1 parts by mass of 2-hydroxyethyl methacrylate, 40.9 parts by mass of methyl methacrylate, 25.7 parts by mass of butyl acrylate, 7.0 parts by mass of styrene, 1.3 parts by mass of acrylic acid, and 5.0 parts by mass of 2,2'-azobis(isobutyronitrile) was added dropwise over 5 hours. Then, while stirring with nitrogen purging at 115°C for 3 hours, the mixture was cooled to 60°C, and propylene glycol monomethyl ether was added to obtain a solution of acrylic polyol resin, namely polyol OHP1, with a solid content of 60% by mass. The weight-average molecular weight (Mw) of polyol OHP1 is 1.21 × 10⁻⁶. 4 The hydroxyl value is 109 mg KOH / g.

[0771] [Manufacturing Example 2-2]

[0772] (Manufacturing of polyol OHP2)

[0773] Propylene glycol monomethyl ether (29 parts by mass) was added to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen inlet. The flask was heated to 110°C under nitrogen purging. After reaching 110°C, nitrogen purging was stopped, and a mixture containing 22.3 parts by mass of 2-hydroxyethyl methacrylate, 8.0 parts by mass of methyl methacrylate, 26.1 parts by mass of butyl acrylate, 42.3 parts by mass of styrene, 1.3 parts by mass of acrylic acid, and 2 parts by mass of 2,2'-azobis(isobutyronitrile) was added dropwise over 5 hours. Then, while stirring with nitrogen purging at 115°C for 3 hours, the mixture was cooled to 60°C, and propylene glycol monomethyl ether was added to obtain a solution of acrylic polyol resin, namely polyol OHP2, with a solid content of 60% by mass. The weight-average molecular weight (Mw) of polyol OHP2 was 2.62 × 10⁻⁶. 4 The hydroxyl value is 139 mg KOH / g.

[0774] [Manufacturing Examples 2-3]

[0775] (Manufacturing of polyol OHP3)

[0776] 25 parts by weight of propylene glycol monomethyl ether were added to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen inlet. The flask was heated to 110°C under nitrogen purging. After reaching 110°C, nitrogen purging was stopped, and a mixture containing 15.2 parts by weight of 2-hydroxyethyl methacrylate, 18.0 parts by weight of 2-ethylhexyl acrylate, 58.3 parts by weight of methyl methacrylate, 7.0 parts by weight of styrene, 1.50 parts by weight of acrylic acid, and 1.5 parts by weight of 2,2'-azobis(isobutyronitrile) was added dropwise over 5 hours. Then, while stirring with nitrogen purging at 115°C for 3 hours, the mixture was cooled to 60°C, and propylene glycol monomethyl ether was added to obtain a solution of 60% by weight of acrylic polyol resin, namely polyol OHP3. The weight-average molecular weight (Mw) of polyol OHP3 was 3.52 × 10⁻⁶. 4 The hydroxyl value is 66 mg KOH / g.

[0777] [Manufacturing Examples 2-4]

[0778] (Manufacturing of polyol OHP4)

[0779] Propylene glycol monomethyl ether (45 parts by weight) was added to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen inlet. The flask was heated to 115°C under nitrogen purging. After reaching 115°C, nitrogen purging was stopped, and a mixture containing 28.2 parts by weight of 2-hydroxyethyl methacrylate, 31.5 parts by weight of methyl methacrylate, 32.0 parts by weight of butyl acrylate, 7.0 parts by weight of styrene, 1.3 parts by weight of acrylic acid, and 8 parts by weight of 2,2'-azobis(isobutyronitrile) was added dropwise over 5 hours. Then, while stirring with nitrogen purging at 115°C for 3 hours, the mixture was cooled to 60°C, and propylene glycol monomethyl ether was added to obtain a solution of acrylic polyol resin, namely polyol OHP4, with a solid content of 60% by weight. The weight-average molecular weight (Mw) of polyol OHP4 was 7.20 × 10⁻⁶. 3 The hydroxyl value is 150 mg KOH / g.

[0780] <Preparation of Resin Compositions>

[0781] [Examples 2-18 to 2-42 and Comparative Examples 2-7 to 2-12]

[0782] (Preparation of resin compositions S-a1 to S-a25 and S-b1 to S-b6)

[0783] The solutions of each polyol were evaporated using an evaporator until the solid content reached 70% by mass. These solutions were then mixed with the end-capped polyisocyanate compositions obtained through the examples or comparative examples, with the molar ratio of isocyanate groups to hydroxyl groups (isocyanate groups / hydroxyl groups) reaching 1. Deionized water was further mixed in, and the mixture was prepared to a solid content of 40% by mass to obtain the resin composition. It should be noted that in resin compositions S-a21 and S-a22 (Examples 2-38 and 2-39), the end-capped polyisocyanate compositions BL-a9 and BL-a10 obtained in Examples 1-9 and 1-10, respectively, were used.

[0784] It should be noted that the types of polyols in Tables 9-13 are as follows.

[0785] (Polyols)

[0786] OHP1: Glass transition temperature (Tg) is 27.2℃, and weight-average molecular weight (Mw) is 1.21 × 10⁻⁶. 4 The hydroxyl value is 109 mg KOH / g (based on solid content).

[0787] OHP2: Glass transition temperature (Tg) is 29.3℃, and weight-average molecular weight (Mw) is 2.62 × 10⁻⁶. 4 The hydroxyl value is 139 mg KOH / g (based on solid content).

[0788] OHP3: Glass transition temperature (Tg) is 44.5℃, and weight-average molecular weight (Mw) is 3.52 × 10⁻⁶. 4 The hydroxyl value is 66 mg KOH / g (based on solid content).

[0789] OHP4: Glass transition temperature (Tg) is 15.2℃, and weight-average molecular weight (Mw) is 7.20 × 10⁻⁶. 3 The hydroxyl value is 150 mg KOH / g (based on solid content).

[0790] Various evaluations were performed on the resin compositions obtained in the Examples and Comparative Examples using the methods described above. The results are shown in Tables 9-13 below. In Tables 9-13, the amount of the capped polyisocyanate composition is expressed as the amount of solids (parts by mass) of the capped polyisocyanate composition relative to 100 parts by mass of the polyol. In Table 13, regarding storage stability, the ratio of viscosity after storage to initial viscosity could not be calculated due to gelation or precipitation.

[0791] [Table 9]

[0792]

[0793] [Table 10]

[0794]

[0795] [Table 11]

[0796]

[0797] [Table 12]

[0798]

[0799] [Table 13]

[0800]

[0801] According to Tables 9-13, the resin compositions S-a1 to S-a25 (Examples 2-18 to 2-42) exhibit good storage stability and good low-temperature curing and tensile strength when formed into resin films.

[0802] Furthermore, in the comparison of resin compositions S-a4~S-a6 and S-a15~S-a17 (Examples 2-21~2-23 and 2-32~2-34) with different types of polyols, and in the comparison of resin compositions S-a8~S-a9 and S-a23~S-a24 (Examples 2-25~2-27 and 2-40~2-42), the following trend can be observed: the lower the glass transition temperature Tg of the polyol and the lower the weight-average molecular weight, the better the storage stability. On the other hand, the following trend can be observed: the higher the glass transition temperature Tg of the polyol and the higher the weight-average molecular weight, the better the low-temperature curing properties and tensile strength when the resin film is made.

[0803] On the other hand, the resin compositions S-b1 to S-b6 (Comparative Examples 2-7 to 2-12) gelled or precipitated during the preparation of the resin compositions, resulting in poor storage stability.

[0804] (End-capping agent)

[0805] B-3: 1,2,3-triazole

[0806] B-4: 1,2,4-triazole

[0807] (solvent)

[0808] DMF: N,N-dimethylformamide

[0809] (Carboxylates)

[0810] C: Potassium acetate

[0811] (Carbamate catalyst)

[0812] LH-10: An aqueous emulsion containing 10% by mass of dibutyltin dilaurate (DBTDL) relative to the total emulsion mass (manufactured by Borchers, "LH-10" (trade name)).

[0813] [Physical Properties 3-1]

[0814] Effective NCO content [mass %)

[0815] = [(Solid content of the capped polyisocyanate composition [mass %]) × {(Mass of polyisocyanate used in the capping reaction) × NCO %}] / (Mass of the capped polyisocyanate composition after the capping reaction)

[0816] [Physical Properties 3-2]

[0817] (Content of counter cations of carboxylates)

[0818] The content of counter cations of carboxylates contained in the capped polyisocyanate composition was determined using the following method.

[0819] First, ultrapure water was added to the sample and mixed, then left to stand for several hours. Afterward, the aqueous layer was filtered and analyzed using ion chromatography to determine the content of the carboxylate countercation. The determination conditions are shown below.

[0820] (Measurement conditions)

[0821] Apparatus: SHIMADZU Corporation, ion chromatograph

[0822] Column: Shim-pack-IC-C4

[0823] 4.6mm ID×150mmL, 7μm (manufactured by SHIMADZU)

[0824] Mobile phase: A) 3.5 mmol / L oxalic acid

[0825] B) 1 mmol / L 18-crown-6

[0826] Flow rate: 1.0 mL / min

[0827] Sample concentration: 1.0% by mass

[0828] Injection volume: 50μL

[0829] Temperature: 45℃

[0830] Detection: CDD

[0831] [Manufacturing Example 3-1]

[0832] <Preparation of capped polyisocyanate compositions>

[0833] (Preparation of the capped polyisocyanate composition BL-a36)

[0834] A nitrogen atmosphere was created in a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen inlet tube. 100 parts by mass of polyisocyanate P-1 obtained in [Synthesis Example 1-1] and 15.0 parts by mass of methoxy polyethylene glycol (MPG-081, ethylene oxide repeating units: 15, manufactured by Nippon Emulsifier Co., Ltd.) (NCO% relative to polyisocyanate P-1: 5 mol%) were added. The mixture was heated to 120°C and stirred for 2 hours. Next, the reaction solution was cooled to approximately 80°C to 110°C, and 30.8 parts by mass of 1,2,3-triazole were slowly added. The reaction was carried out at a temperature of 80°C to 120°C with stirring for approximately 1 hour to 4 hours. Subsequently, FT-IR spectra were measured to confirm that the isocyanate groups were capped. Then, N,N-dimethylformamide was added to the reaction solution to achieve a solid content of 60%, and the mixture was stirred at 60°C until homogeneous. Next, the mixture was cooled to 30°C, and the aforementioned D-1 (polyoxyethylene polycyclic phenyl ether ammonium sulfate (polyoxyethylene (oxyethylene (oxoethylene repeating number n = 10-15) alkyl (alkyl carbon number C = 1, 8, 9) (mono-penta) styrene-phenyl ether ammonium sulfate) (surface tension at 25°C is 40.3 mM / m)) as a dispersant was added to the reaction solution as a dispersant in a manner that is 1.5 parts by mass relative to 100 parts by mass of the solid component of the capped polyisocyanate) and stirred for another 30 minutes to obtain the capped polyisocyanate composition BL-a36.

[0835] [Manufacturing Example 3-2]

[0836] <Preparation of capped polyisocyanate compositions>

[0837] (Preparation of the capped polyisocyanate composition BL-a37)

[0838] Except for using the aforementioned D-2 (sodium sulfate of polyoxyethylene polycyclic phenyl ether (sodium sulfate of polyoxyethylene (repeating number of oxyethylene ethylene n = 10 to 15) alkyl (carbon number of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether (surface tension at 25°C is 41.5 mN / m)) as a dispersant, the same procedure as in Manufacturing Example 3-1 was followed to obtain the end-capped polyisocyanate composition BL-a37.

[0839] [Manufacturing Example 3-3]

[0840] <Preparation of capped polyisocyanate compositions>

[0841] (Preparation of the capped polyisocyanate composition BL-a38)

[0842] Except for using the aforementioned D-3 (polyoxyethylene alkyl ether ammonium sulfate (compound (II-2) (surface tension of 40.4 mN / m at 25°C)) as a dispersant, the same procedure as in Manufacturing Example 3-1 was followed to obtain the end-capped polyisocyanate composition BL-a38.

[0843] [Manufacturing Examples 3-4]

[0844] (Preparation of the capped polyisocyanate composition BL-a39)

[0845] A nitrogen atmosphere was created in a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen inlet tube. 100 parts by mass of polyisocyanate P-1 obtained in [Synthesis Example 1-1] and 15.0 parts by mass of methoxy polyethylene glycol (MPG-081, ethylene oxide repeating unit: 15, manufactured by Nippon Emulsifier Co., Ltd.) were added. The mixture was heated to 120°C and stirred for 2 hours. Next, the reaction solution was cooled to approximately 80°C to 110°C, and 30.8 parts by mass of 1,2,4-triazole were slowly added. The reaction was carried out at a temperature of 80°C to 120°C with stirring for at least 1 hour and approximately 4 hours. Subsequently, FT-IR spectra were measured to confirm that the isocyanate groups were capped. Next, N,N-dimethylformamide was added to the reaction solution with a solid content of 60%, and the mixture was stirred at 60°C until homogeneous. Then, the mixture was cooled to 30°C, and the aforementioned D-1 (polyoxyethylene polycyclic phenyl ether ammonium sulfate (polyoxyethylene (oxyethylene (oxyethylene (the number of repeating ethylenes n = 10-15) alkyl (the number of carbon atoms of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether ammonium sulfate) (the surface tension at 25°C is 40.3 mM / m)) as a dispersant was added to the reaction solution with a solid content of 1.5 parts by mass relative to 100 parts by mass of the end-capped polyisocyanate) and the mixture was stirred for another 30 minutes to obtain the end-capped polyisocyanate composition BL-a39.

[0846] [Manufacturing Examples 3-5]

[0847] <Preparation of capped polyisocyanate compositions>

[0848] (Preparation of the capped polyisocyanate composition BL-a40)

[0849] Except for using the aforementioned D-2 (sodium sulfate of polyoxyethylene polycyclic phenyl ether (sodium sulfate of polyoxyethylene (repeating number of oxyethylene ethylene n = 10 to 15) alkyl (carbon number of alkyl C = 1, 8, 9) (mono- to penta) styrene-phenyl ether (surface tension at 25°C is 41.5 mN / m)) as a dispersant, the same procedure as in Manufacturing Examples 3-4 was followed to obtain the end-capped polyisocyanate composition BL-a40.

[0850] [Manufacturing Examples 3-6]

[0851] <Preparation of capped polyisocyanate compositions>

[0852] (Preparation of the capped polyisocyanate composition BL-a41)

[0853] Except for using the aforementioned D-3 (polyoxyethylene alkyl ether ammonium sulfate (compound (II-2) (surface tension of 40.4 mN / m at 25°C)) as a dispersant, the same procedure as in Manufacturing Examples 3-4 was followed to obtain the end-capped polyisocyanate composition BL-a41.

[0854] [Manufacturing Examples 3-7]

[0855] <Preparation of capped polyisocyanate compositions>

[0856] (Preparation of the capped polyisocyanate composition BL-a42)

[0857] Except for adding dispersant D-3 in such a way that 0.5 parts by mass are added relative to 100 parts by mass of the solid component of the capped polyisocyanate, the same procedure as in manufacturing examples 3-6 was followed to obtain the capped polyisocyanate composition BL-a42.

[0858] <Preparation of Resin Compositions>

[0859] [Example 3-1]

[0860] Aqueous acrylic polyol (Setaqua 6515, a registered trademark manufactured by Nuplex, with OH (%) (on solids) = 3.3, acid value (mgKOH / g) = 9.9, and resin content of 45%): 10.0 parts by weight (solution weight) and capped polyisocyanate BL-a36: 4.08 parts by weight (solution weight) (in a manner where the molar ratio of isocyanate groups to hydroxyl groups (isocyanate groups / hydroxyl groups) reaches 0.80) were mixed. Next, potassium acetate: 0.14 parts by weight (0.80% by weight relative to the total solids of the resin) and 10% by weight of dibutyltin dilaurate (DBTDL, (Borchers, "LH-10" (trade name)): 0.14 parts by weight (solution weight, 0.80% by weight relative to the total solids of the resin) were added. After further mixing with deionized water, the resin was prepared to a solids content of 40% by weight. A trace amount of dimethylaminoethanol was added, the pH was adjusted to 8.0-8.5, and the mixture was stirred at 1000 rpm for 15 minutes using a homogenizer to obtain the resin composition.

[0861] [Examples 3-2 to 3-7]

[0862] Each end-capped polyisocyanate BL-a37 to 42 was mixed such that the molar ratio of isocyanate groups to hydroxyl groups (isocyanate groups / hydroxyl groups) reached 0.80; potassium acetate was mixed such that it reached 0.80% by weight relative to the total solids of the resin; and 10% by weight of dibutyltin dilaurate was added such that it reached 0.80% by weight relative to the total solids of the resin. Otherwise, the same procedure as in Example 3-1 was followed to obtain the resin composition.

[0863] [Evaluation 3-1] Storage stability

[0864] For 20g of the obtained resin composition, the initial viscosity and the viscosity after storage at 40°C for 10 days in a 20mL glass bottle were measured (viscometer: RE-85R manufactured by Toki Sangyo Co., Ltd.). The ratio of the stored viscosity to the initial viscosity was calculated. It should be noted that a stored viscosity ratio of 2.5 or less, indicating no gelation or precipitation, is considered good. A stored viscosity ratio greater than 1, with values ​​close to 1 and less than 1, is considered particularly good.

[0865] [Evaluation 3-2] Low-temperature curing properties

[0866] The obtained resin composition was coated onto a polypropylene (PP) plate to achieve a dry film thickness of 40 μm, and then dried at 90°C for 30 minutes to obtain a resin film. The resin film was then stored at room temperature (23°C) for one week, and the gelation rate was determined. The gelation rate was expressed as a percentage (mass%) of the undissolved portion of the resin film after immersion in acetone at 23°C for 24 hours, divided by the initial mass. It should be noted that a gelation rate of 80% or higher is considered good.

[0867] [Table 14]

[0868]

[0869] <Methods for Determining Physical Properties>

[0870] [Physical Properties 4-1]

[0871] (Modification rate)

[0872] Using a hydrophilic polyisocyanate composition as a sample, the following method was used to determine the ratio of the total molar amount of isocyanate groups modified with the aforementioned hydrophilic compound to the total molar amount of isocyanate groups in the alicyclic polyisocyanate. This ratio can also be referred to as the ratio of 100 mol% of isocyanate groups modified with the hydrophilic compound to the isocyanate groups in the raw polyisocyanate (modification rate). Specifically, it was determined by the peak area ratio of unmodified IPDI-based isocyanurate polyisocyanates, single-modified IPDI-based isocyanurate polyisocyanates, double-modified IPDI-based isocyanurate polyisocyanates, and triple-modified IPDI-based isocyanurate polyisocyanates at 220 nm using liquid chromatography (LC). The apparatus and measurement conditions used are shown below.

[0873] (Apparatus and Measurement Conditions)

[0874] LC device: Waters Corporation, UPLC (trade name)

[0875] Column: Waters Corporation, ACQUITY UPLC HSS T3 1.8μm C18, inner diameter 2.1mm × length 50mm

[0876] Flow rate: 0.3 mL / min

[0877] Mobile phase: A = 10 mM ammonium acetate aqueous solution, B = acetonitrile

[0878] Gradient conditions: The initial mobile phase composition is A / B = 98 / 2. After the sample is injected, the ratio of B increases linearly, and after 10 minutes, A / B = 0 / 100 is set.

[0879] Detection method: photodiode array detector, measurement wavelength 220nm

[0880] [Physical Properties 4-2]

[0881] (Solid content)

[0882] Hydrophilic polyisocyanate compositions or capped polyisocyanate compositions were used as samples.

[0883] First, accurately weigh an aluminum dish with a bottom diameter of 38 mm. Next, accurately weigh approximately 1 g of sample on the aluminum dish (W1). Then, adjust the sample to a uniform thickness. Next, place the sample on the aluminum dish in an oven at 105°C for 1 hour. Next, after the aluminum dish reaches room temperature, accurately weigh the remaining sample on the dish (W2). Then, calculate the solid content (mass %) of the sample using the following formula.

[0884] Solid content (mass%) = W2 / W1 × 100

[0885] [Physical Properties 4-3]

[0886] (Isocyanate group content (NCO%))

[0887] The polyisocyanate and hydrophilic polyisocyanate composition used as raw materials 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 Carbamate Elastomers). A more specific method for determining the isocyanate group content is shown below.

[0888] (1) Take 1g (Wg) of the sample into a 200mL conical flask, add 20mL of toluene to the flask to dissolve the sample.

[0889] (2) Subsequently, add 20 mL of 2.0 N di-n-butylamine-toluene solution to the above flask and let stand for 15 minutes.

[0890] (3) Add 70 mL of 2-propanol to the above flask to dissolve it and obtain a solution.

[0891] (4) For the solution obtained in (3) above, titrate with 1 mol / L hydrochloric acid to determine the sample titration amount (V1 mL).

[0892] (5) Without adding a sample, the same method as (1) to (3) above is used to determine the blank titration amount (V0mL).

[0893] The isocyanate group content (NCO%) can be calculated from the sample titration and blank titration obtained above using the formula shown below.

[0894] [Isocyanate group content] (mass%) = (V0-V1)×42 / [W(1g)×1000]×100

[0895] [Physical Properties 4-4]

[0896] (Number average molecular weight (Mn) and weight average molecular weight (Mw))

[0897] The number-average molecular weight (Mn) of the polyisocyanate used as raw material and the weight-average molecular weight (Mw) of the hydrophilic polyisocyanate composition were determined by GPC under the determination conditions shown below, and the number-average molecular weight and weight-average molecular weight of polystyrene were determined.

[0898] (Measurement conditions)

[0899] Device: Tosoh HLC-8120GPC (trade name)

[0900] Pillar: 1 x TSK gel Super H1000 (product name) from Tosoh Corporation

[0901] TSK gel Super H2000 (product name) × 1 stick

[0902] TSK gel Super H3000 (product name) × 1 stick

[0903] Support: Tetrahydrofuran

[0904] Test method: Differential refractometer

[0905] [Physical Properties 4-5]

[0906] (Average number of functional groups of isocyanate group (average number of NCOs))

[0907] The average number of isocyanate groups (average NCO number) in the polyisocyanate before hydrophilization (before modification with hydrophilic compounds), i.e., the raw material polyisocyanate, is determined using the following formula. It should be noted that in the formula, "Mn" is the number-average molecular weight of the raw material polyisocyanate, using the value obtained from "Property 4-4" above. "NCO%" is the isocyanate group content of the raw material polyisocyanate, using the value calculated from "Property 4-3" above.

[0908] [Average NCO count] = (Mn × [NCO%] × 0.01) / 42

[0909] <Evaluation Methods>

[0910] [Rating 4-1]

[0911] (Water dispersibility)

[0912] Ion-exchanged water was added to a hydrophilic polyisocyanate composition or a capped polyisocyanate composition such that the solid content was 40% by mass relative to the total mass of the aqueous dispersion. The mixture was stirred at 1000 rpm for 5 minutes using a dispersant mixer, followed by degassing to obtain an aqueous dispersion. The water dispersibility of the obtained aqueous dispersion was evaluated according to the following evaluation criteria.

[0913] (Evaluation Criteria)

[0914] A: Liquid state with no sediment and visible clumps.

[0915] B: No sediment, partially confirmed liquid state with visible clumps.

[0916] C: The precipitate is thin and locally confirmed to be in a liquid state with visible clumps.

[0917] D: The precipitation of precipitates can be clearly identified, or a large amount of liquid clumps can be visually identified.

[0918] [Preparation of the resin composition]

[0919] An acrylic dispersion (Allnex, "SETAQUA 6515" (trade name), with a hydroxyl concentration of 3.3 mol% (resin basis) and a solid content of 45% by mass relative to the total mass of the acrylic dispersion) was mixed with a hydrophilic polyisocyanate composition or a capped polyisocyanate composition such that the molar ratio of isocyanate groups to hydroxyl groups (isocyanate groups / hydroxyl groups) reached 1. Deionized water was further mixed in to prepare the resin composition with a solid content of 40% by mass relative to the total mass of the resin composition. The mixture was stirred at 1000 rpm for 10 minutes using a dispersant mixer to obtain the resin composition.

[0920] [Rating 4-2]

[0921] (König hardness)

[0922] The obtained resin composition was coated onto a glass plate to achieve a dry film thickness of 40 μm, and then dried at 80 °C for 30 minutes to obtain a resin film. The König hardness (in cycles) of the obtained resin film was measured using a König hardness tester.

[0923] [Rating 4-3]

[0924] (Low-temperature curing properties)

[0925] Using the same method as described in "Evaluation 4-2" above, the resin film was coated onto a polypropylene (PP) plate to achieve a dry film thickness of 40 μm. Then, it was heated and dried at 80°C for 30 minutes to obtain the resin film. After storing the obtained resin film at room temperature (23°C) for one week, the gelation rate was determined. The gelation rate was calculated as a percentage (mass%) of the undissolved portion of the resin film after immersion in acetone at 23°C for 24 hours, divided by the mass before immersion. It should be noted that a gelation rate of 75% or higher is considered good.

[0926] <Preparation of hydrophilic polyisocyanate compositions>

[0927] [Example 4-1]

[0928] (Preparation of the hydrophilic polyisocyanate composition P-a1)

[0929] Under a nitrogen atmosphere, in a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser, a mixture of 100 parts by weight of a polyisocyanate based on isophorone diisocyanate (hereinafter sometimes abbreviated as "IPDI-based isocyanurate type PI"), 8.3 parts by weight of methoxy polyethylene glycol ("MPG-081" (trade name), 15 repeating ethylene oxide units, manufactured by Nippon Emulsifier Co., Ltd., in an amount where ethylene oxide reaches 3 mol% relative to 100 mol% of isocyanate groups), and dipropylene glycol dimethyl ether (DPDM) was reacted at 115°C for 2 hours. The reaction mixture was then cooled to 40°C to obtain a hydrophilic polyisocyanate composition P-a1 with a solid content of 60.1 mol% by weight.

[0930] [Examples 4-2 to 4-6 and Comparative Examples 4-1 to 4-4]

[0931] (Preparation of hydrophilic polyisocyanate compositions P-a2~P-a6 and P-b1~P-b4)

[0932] Methoxy polyethylene glycol MPG-081, as a hydrophilic compound, was compounded in such a manner that the molar amount (modification rate) of ethylene oxide relative to isocyanate groups of 100 mol% reached the values ​​described in Tables 1 and 2. Otherwise, each hydrophilic polyisocyanate composition was obtained using the same method as in Examples 4-1.

[0933] For each hydrophilic polyisocyanate composition obtained in the Examples and Comparative Examples, the physical properties were determined using the methods described above, and various evaluations were performed. The results are shown in Tables 15 and 16.

[0934] [Table 15]

[0935]

[0936] [Table 16]

[0937]

[0938] According to Tables 15-16, the hydrophilic polyisocyanate compositions P-a1 to P-a6 (Examples 4-1 to 4-6) with a modification rate of 3 mol% or more and 15 mol% or less exhibit good water dispersibility and excellent König hardness when formed into resin films.

[0939] Furthermore, compositions P-a2 to P-a5 (Examples 4-2 to 4-5) with a modification rate of 5 mol% or more and 12 mol% or less exhibit particularly good water dispersibility.

[0940] On the other hand, the hydrophilic polyisocyanate compositions P-b1 to P-b4 (Comparative Examples 4-1 to 4-4) with a modification rate of less than 2 mol% or more than 15 mol% exhibit poor water dispersibility and König hardness when forming resin films.

[0941] <Preparation of capped polyisocyanate compositions>

[0942] [Examples 4-7]

[0943] (Preparation of the capped polyisocyanate composition BP-a1)

[0944] For the hydrophilic polyisocyanate composition P-a1 obtained by Example 4-1, diisopropyl malonate (B-2) as a capping agent was added in a molar amount relative to the isocyanate groups to reach 1.1 molar equivalents. Further, 1.0 part by mass (based on solution amount) of a methanol solution containing 28% by mass of sodium methoxide relative to the total mass of the solution was added, and DPDM was added in a solid content amount of 60% by mass, followed by stirring. The inner bath was maintained at 55°C and stirred for at least 6 hours. The disappearance of the characteristic absorption of the isocyanate groups was confirmed by infrared spectroscopy. Subsequently, a capped polyisocyanate composition BP-a1 with a solid content of 60.1% by mass was obtained.

[0945] [Examples 4-8 to 4-12 and Comparative Examples 4-5 to 4-8]

[0946] (Preparation of end-capped polyisocyanate compositions BP-a2~BP-a6 and BP-b1~BP-b8)

[0947] Except for using the hydrophilic polyisocyanate compositions and end-capping agents shown in Tables 17 and 18 instead of the hydrophilic polyisocyanate composition P-a1, the end-capped polyisocyanate compositions were obtained using the same method as in Examples 4-7.

[0948] [Example 4-13]

[0949] (Preparation of the capped polyisocyanate composition BP-a7)

[0950] For the hydrophilic polyisocyanate composition P-a2 obtained by Example 4-2, di-tert-butyl malonate (B-1) as a capping agent was added in a molar amount of 1.1 mol equivalents relative to the isocyanate groups. Further, 1.0 part by mass (based on solution weight) of a methanol solution containing 28% sodium methoxide relative to the total mass of the solution was added, and DPDM was added in a solids content of 60% by mass. The mixture was stirred. The inner bath was maintained at 55°C and stirred for at least 6 hours. The disappearance of the characteristic absorption of the isocyanate groups was confirmed by infrared spectroscopy. Subsequently, a capped polyisocyanate composition BP-a7 with a solids content of 60.1% by mass was obtained.

[0951] [Example 4-14]

[0952] (Preparation of the capped polyisocyanate composition BP-a8)

[0953] Except that the hydrophilic polyisocyanate composition P-a3 obtained by Example 4-3 was used instead of the hydrophilic polyisocyanate composition P-a2 obtained by Example 4-2, the end-capped polyisocyanate composition BP-a8 was obtained using the same method as in Example 4-13.

[0954] For each end-capped polyisocyanate composition obtained in the Examples and Comparative Examples, physical properties were determined using the methods described above, and various evaluations were performed. The results are shown in Tables 17 and 18.

[0955] [Table 17]

[0956]

[0957] [Table 18]

[0958]

[0959] According to Tables 17 and 18, the end-capped polyisocyanate compositions BP-a1 to BP-a8 (Examples 4-7 to 4-14) using hydrophilic polyisocyanate compositions with a modification rate of 3 mol% or more and 15 mol% or less exhibit good water dispersibility, excellent König hardness and low-temperature curability when made into resin films.

[0960] Furthermore, as the modification rate in the hydrophilic polyisocyanate composition used increases, a tendency towards better water dispersibility and lower-temperature curing properties when forming resin films is observed. On the other hand, as the modification rate in the hydrophilic polyisocyanate composition used decreases, a tendency towards better König hardness when forming resin films is observed.

[0961] Furthermore, the polyisocyanate compositions BP-a7 and BP-a8 (Examples 4-13 and 4-14) using di-tert-butyl malonate as the end-capping agent exhibit superior König hardness and low-temperature curability when formed into resin films compared to the polyisocyanate compositions BP-a2 and BP-a3 (Examples 4-8 and 4-9) using diisopropyl malonate as the end-capping agent.

[0962] On the other hand, the end-capped polyisocyanate compositions BP-b1 to BP-b4 (Comparative Examples 4-5 to 4-8) using hydrophilic polyisocyanate compositions with a modification rate of less than 2 mol% or more than 15 mol% exhibit poor water dispersibility, hardness when forming resin films, and low-temperature curing properties.

[0963] [Example 4-15]

[0964] (Synthesis of polyisocyanate P-c1)

[0965] Under a nitrogen atmosphere, 100 parts by mass of HDI and 5.2 parts by mass of a polyester polyol derived from triol and ε-caprolactone (manufactured by Dassault Chemicals, "PLACCEL 303" (trade name)) were added to a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser. The temperature inside the reactor was maintained at 90°C for 1 hour with stirring to carry out the carbamate reaction. Subsequently, the temperature inside the reactor was maintained at 60°C, and the isocyanurate esterification catalyst, tetramethyldecanoate ammonium, was added. Phosphoric acid was added when the yield reached 51% by mass to stop the reaction. The reaction solution was filtered, and unreacted HDI was removed using a thin-film evaporator to obtain isocyanurate-type polyisocyanates (hereinafter sometimes referred to as "polyisocyanate P-c1").

[0966] The obtained polyisocyanate P-c1 had an NCO content of 18.7% by mass, a number-average molecular weight of 1140, and an average isocyanate group number of 5.1. Furthermore, GPC analysis was performed on the obtained polyisocyanate P-c1. 1 H-NMR analysis confirmed the presence of isocyanurate trimer.

[0967] [Example 4-16]

[0968] (Preparation of the capped polyisocyanate composition BP-c1)

[0969] Under a nitrogen atmosphere, in a four-necked flask equipped with a thermometer, stirring blades, and a reflux condenser, a reaction was carried out at 115°C for 2 hours to achieve a solid content concentration of 65% by weight, consisting of 100 parts by weight of polyisocyanate P-c1 obtained in Examples 4-15, 1.5 parts by weight of methoxy polyethylene glycol (MPG-081, ethylene oxide repeating unit: 15, manufactured by Nippon Emulsifier Co., Ltd.), 0.01 parts by weight of 2-ethylhexyl phosphate (JP-508T, manufactured by Jōhoku Chemical Co., Ltd.), and dipropylene glycol dimethyl ether (DPDM). The reaction solution was cooled to 40°C, and di-tert-butyl malonate was added as a capping agent in an amount of 1.1 mol equivalent relative to the molar amount of isocyanate groups in the reactants. Further, 1.0 parts by weight of a methanol solution containing sodium methoxide (28% by weight) was added, and the mixture was stirred. The inner bath was maintained at 48°C and stirred for more than 6 hours. The characteristic absorption of the isocyanate group was confirmed to have disappeared by infrared spectroscopy. DPDM was added in a manner that reached 60% by mass of solid content and stirred. The mixture was then cooled to below 40°C to obtain the end-capped polyisocyanate composition BP-c1.

[0970] [Example 4-17]

[0971] (Preparation of the capped polyisocyanate composition BP-d1)

[0972] Under a nitrogen gas flow, in a four-necked flask equipped with a thermometer, stirring blades and a reflux condenser, the end-capped polyisocyanate composition BP-c1 and BP-a7 were blended at a molar ratio of 95:5 for NCO and stirred for 30 minutes to obtain an end-capped polyisocyanate composition BP-d1 with a solid content of 60.1% by mass.

[0973] [Examples 4-18 to 4-20]

[0974] Examples 4-18-4-20: End-capped polyisocyanate compositions were prepared according to Table 19 using the same method as in Examples 4-17.

[0975] The physical properties of each of the obtained end-capped polyisocyanate compositions were determined using the above method, and various evaluations were performed. The results are shown in Table 19.

[0976] [Table 19]

[0977]

[0978] Industrial availability

[0979] The end-capped polyisocyanate composition according to this embodiment provides a resin composition with good storage stability. Furthermore, it can form a resin film with good curability at a low temperature of around 80°C, thus making it suitable for coating materials with low heat resistance.

[0980] Furthermore, the hydrophilic polyisocyanate composition according to this embodiment can provide a resin film with good water dispersibility and excellent hardness.

Claims

1. A capped polyisocyanate composition, which is formed by capping at least a portion of the isocyanate groups in a hydrophilic polyisocyanate composition with a capping agent, said hydrophilic polyisocyanate composition being a hydrophilic polyisocyanate composition derived from a hydrophilic compound and an alicyclic polyisocyanate having isocyanurate groups. The proportion of isocyanate groups modified with the hydrophilic compound to the total molar amount of isocyanate groups in the alicyclic polyisocyanate is 2 mol% or more and 7 mol% or less. The hydrophilic polyisocyanate composition does not contain any additional polyisocyanates different from alicyclic polyisocyanates, and the weight-average molecular weight of the hydrophilic polyisocyanate composition is 900 or more and 20,000 or less. in, The alicyclic polyisocyanate comprises a polyisocyanate having an isocyanurate group derived from isophorone diisocyanate, and the alicyclic polyisocyanate has an average number of isocyanate groups of 2.5 or more and 6.0 or less. The capping agent is selected from at least one compound chosen from the group consisting of active methylene compounds, oxime compounds, pyrazole compounds, and triazole compounds.

2. A capped polyisocyanate composition, which is formed by sealing at least a portion of the isocyanate groups in a hydrophilic polyisocyanate composition with a capping agent, said hydrophilic polyisocyanate composition being a hydrophilic polyisocyanate composition derived from a hydrophilic compound and an alicyclic polyisocyanate having isocyanurate groups. The proportion of isocyanate groups modified with the hydrophilic compound to the total molar amount of isocyanate groups in the alicyclic polyisocyanate is 2 mol% or more and 7 mol% or less. The hydrophilic polyisocyanate composition contains only alicyclic polyisocyanates as polyisocyanates, and the weight-average molecular weight of the hydrophilic polyisocyanate composition is 900 or more and 20,000 or less. in, The alicyclic polyisocyanate comprises a polyisocyanate having an isocyanurate group derived from isophorone diisocyanate, and the alicyclic polyisocyanate has an average number of isocyanate groups of 2.5 or more and 6.0 or less. The capping agent is an amine compound.

3. The terminated polyisocyanate composition according to claim 1 or 2, wherein, The alicyclic polyisocyanate has an average number of isocyanate groups of 2.9 or more and 5.5 or less.

4. The terminated polyisocyanate composition according to claim 1 or 2, wherein, The hydrophilic compound is a nonionic compound or anionic compound.

5. A resin composition comprising the end-capped polyisocyanate composition according to any one of claims 1 to 4 and a polyol.

6. A resin film formed by curing the resin composition of claim 5.

Images