Aqueous dispersions of polyurethane resins and their manufacturing methods, including gas barrier films

Abstract

This invention provides an aqueous dispersion of polyhydroxycarbamate that can form a film layer with excellent gas barrier properties and metal / metal oxide adhesion. The aqueous dispersion system of the polyhydroxycarbamate resin of this invention contains water and polyhydroxycarbamate resin dispersed in water; the polyhydroxycarbamate resin contains the following repeating unit (i) as a basic structure: a compound (A) of the following general formula (1) (R1 represents a hydrocarbon group with 6 to 16 carbon atoms containing a ring structure) and a compound (B) of the following general formula (2) (R2 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, R3 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, etc.) are polymerized, and then a repeating unit (i) of COOM group is introduced after polymerization; the repeating unit (i) contains the structural part of the following general formula (3) (R2 and R3 are synonyms with R2 and R3 in general formula (2), respectively; X represents an aliphatic hydrocarbon group with 1 to 10 carbon atoms; M represents a hydrogen atom or a relative ion).

Description

Technical Field

[0001] This invention relates to an aqueous dispersion of polyhydroxycarbamate resin and its manufacturing method, as well as a gas barrier film. Prior Technology

[0002] Polyurethane resins (polyhydroxycarbamates), which incorporate urethane bonds and hydroxyl groups into their chemical structure, can be manufactured by combining epoxy compounds, carbon dioxide, and amine compounds as raw materials. Since carbon dioxide is incorporated into the chemical structure of polyhydroxycarbamates in the form of -CO-O- bonds, it is a resin material of interest from the perspective of effectively utilizing carbon dioxide, a greenhouse gas. Furthermore, polyhydroxycarbamates possess hydroxyl groups, which are not present in the structure of conventional polyurethane resins obtained from isocyanate compounds and polyols. Applications utilizing the functions of these hydroxyl groups (e.g., in barrier films) are also being explored.

[0003] Polyhydroxycarbamates are expected to be used in coatings and other coating agents. However, due to the presence of ethyl carbamate bonds and hydroxyl groups in their chemical structure, they have low solubility in organic solvents, making them difficult to use with various solvent compositions, which hinders their application. In contrast, as disclosed in Patent Document 1, a polyhydroxycarbamate aqueous dispersion, formed by dispersing polyhydroxycarbamates in water, is expected to be used in water-based coatings and other water-based coating agents.

[0004] In Patent Document 1, to obtain an aqueous dispersion of polyurethane, it is proposed to introduce a neutralizable carboxylic acid by half-esterifying the hydroxyl groups in the polyurethane with an anhydride. However, since the half-esterification of the hydroxyl groups introduces carboxyl groups, the dispersion stability of the aqueous dispersion is reduced due to the hydrolysis of the half-ester portion. Furthermore, the use of the hydroxyl groups in the reaction reduces the number of hydroxyl groups, making it difficult to fully utilize the functions derived from the hydroxyl groups.

[0005] In contrast, a technology for introducing carboxyl groups into polyhydroxycarbamates via amide bonds has been proposed (Patent Document 2). [Previous Technical Documents] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2007-297544 [Patent Document 2] Japanese Patent Application Publication No. 2018-070840 Summary of the Invention

[0007] (The problem the invention aims to solve) According to the technology proposed in Patent Document 2, an aqueous dispersion of polyhydroxycarbamate can be obtained that can form a coating layer with excellent gas barrier properties and excellent dispersion stability. However, the coating layer formed may not have good adhesion to metals such as metal vapor-deposited layers, and there is still room for improvement.

[0008] This invention addresses the problems of the prior art, and its objective is to provide an aqueous dispersion of polyurethane that can form a coating layer with excellent gas barrier properties and metal-metal oxide adhesion. Furthermore, according to this invention, a method for manufacturing this aqueous dispersion of polyurethane is provided, as well as a gas barrier film having excellent gas barrier properties and metal-metal oxide adhesion. (Technical means to solve the problem)

[0009] That is, according to the present invention, an aqueous dispersion of the polyhydroxycarbamate resin shown below is provided. [1] An aqueous dispersion of a polyhydroxycarbamate resin, comprising water and a polyhydroxycarbamate resin with an average particle size of 1 to 10,000 nm dispersed in the water; the polyhydroxycarbamate resin comprises a repeating unit (i) as a basic structure, the repeating unit (i) being polymerized from a compound (A) of the general formula (1) and a compound (B) of the general formula (2), and then having a COOM group introduced after polymerization; the repeating unit (i) comprises a structural part of the general formula (3).

[0010] (In the general formula (1) above, R1 represents a hydrocarbon group with 6 to 16 carbon atoms containing a ring structure).

[0011] (In the above general formula (2), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms, and R3 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms).

[0012] (In the above general formula (3), R1 is synonymous with R1 in the above general formula (1), and R2 and R3 are synonymous with R2 and R3 in the above general formula (2), respectively; X represents an aliphatic hydrocarbon group with 1 to 10 carbon atoms or an aromatic hydrocarbon group with 6 to 10 carbon atoms that may also contain oxygen or nitrogen atoms; M represents a hydrogen atom or a relative ion used to form a salt structure).

[0013] [2] An aqueous dispersion of polyhydroxylamine carbamate resin as described in [1], wherein the weight average molecular weight of the polyhydroxylamine carbamate resin is 10,000 to 150,000, the acid value is 15 to 60 mg KOH / g, and the hydroxyl value is 150 to 250 mg KOH / g.

[0014] Furthermore, according to the present invention, a method for manufacturing an aqueous dispersion of the polyhydroxycarbamate resin shown below is provided. [3] A method for manufacturing an aqueous dispersion of a polyhydroxycarbamate resin, which is the method for manufacturing an aqueous dispersion of a polyhydroxycarbamate resin described in [1] or [2] above, comprises the following steps: reacting a diisocyanate compound of the following general formula (4) with a compound of the following formula (5) to obtain the above compound (A); reacting a diamine compound of the following general formula (6) with a diglycidyl compound of the following general formula (7) to obtain a reactant containing the above compound (B); subjecting the obtained above compound (A) to a polyaddition reaction with the above reactant to obtain a polymer; and reacting the obtained polymer with an anhydride having a cyclic anhydride structure to obtain a polyhydroxycarbamate resin having a carboxyl group.

[0015] (In the above general formula (4), R1 represents a hydrocarbon group with 6 to 16 carbons containing a ring structure; in the above general formula (6), R3 represents an aliphatic hydrocarbon group with 1 to 12 carbons, an alicyclic hydrocarbon group with 4 to 16 carbons, or an aromatic hydrocarbon group with 6 to 18 carbons; in the above general formula (7), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbons, an alicyclic hydrocarbon group with 4 to 16 carbons, or an aromatic hydrocarbon group with 6 to 18 carbons).

[0016] [4] The method for manufacturing an aqueous dispersion of polyhydroxylamine carboxylate resin as described in [3] further comprises: neutralizing the carboxyl groups of the above-mentioned polyhydroxylamine carboxylate resin having carboxyl groups with an alkali, and then mixing it with water to perform phase inversion emulsification. [5] A method for manufacturing an aqueous dispersion of polyhydroxylamine formate resin as described in [3] or [4], wherein the diamine compound and the diglycidyl compound are reacted under the condition that the equivalence ratio of amino group to glycidyl group is 4 / 1 or more, to obtain the reactant. [6] A method for manufacturing an aqueous dispersion of polyhydroxylamine carbamate resin as described in any of [3] to [5], wherein the acid anhydride is selected from at least one of the group consisting of maleic anhydride, pyromellitic anhydride and succinic anhydride.

[0017] Furthermore, according to the present invention, a gas barrier film as shown below is provided. [7] A gas barrier film comprises: a substrate film; and a coating layer disposed on at least one side of the substrate film, which contains a polyhydroxycarbamate resin constituting an aqueous dispersion of the polyhydroxycarbamate resin of [1] or [2]. (Compared to the effectiveness of previous technologies)

[0018] According to the present invention, an aqueous dispersion of polyhydroxycarbamate that can form a coating layer with excellent gas barrier properties and metal-metal oxide adhesion is provided. Furthermore, according to the present invention, a method for manufacturing this aqueous dispersion of polyhydroxycarbamate, and a gas barrier film having a coating layer with excellent gas barrier properties and metal-metal oxide adhesion are provided. Implementation

[0019] <Aqueous Dispersions of Polyurethane> The following describes embodiments of the present invention, but the present invention is not limited to the following embodiments. One embodiment of the aqueous dispersion of polyhydroxycarbamate of the present invention (hereinafter also simply referred to as "aqueous dispersion") contains water and a polyhydroxycarbamate resin dispersed in water with an average particle size of 1 to 10,000 nm. The polyhydroxycarbamate resin contains the following repeating unit (i) as its basic structure: a repeating unit (i) is introduced after polymerization of compound (A) shown in general formula (1) and compound (B) shown in general formula (2). Moreover, this repeating unit (i) contains the structural part shown in general formula (3). The aqueous dispersion of polyhydroxycarbamate of the present invention will be described in detail below.

[0020] (In the general formula (1) above, R1 represents a hydrocarbon group with 6 to 16 carbon atoms containing a ring structure).

[0021] (In the above general formula (2), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms, and R3 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms).

[0022] (In the above general formula (3), R1 is synonymous with R1 in the above general formula (1), and R2 and R3 are synonymous with R2 and R3 in the above general formula (2), respectively; X represents an aliphatic hydrocarbon group with 1 to 10 carbon atoms or an aromatic hydrocarbon group with 6 to 10 carbon atoms, which may also contain oxygen or nitrogen atoms; M represents a hydrogen atom or a relative ion used to form a salt structure).

[0023] In this specification, the term "group derived from a compound" refers to a group present in or derived from that compound. Furthermore, the term "organic group" refers to a group containing at least a carbon atom, and may also contain atoms other than carbon and hydrogen (e.g., oxygen, nitrogen, sulfur, and halogen atoms). This hydrocarbon group can be an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or any combination of two or more of these groups, and may also have substituents. Aromatic hydrocarbon groups can be condensed rings or linked rings.

[0024] Polyhydroxylamine ester resin is a resin having a repeating unit (i) containing the structural part shown in general formula (3) as its basic structure. This repeating unit (i) is a constituent unit formed by introducing a COOM group after the polymerization of compound (A) shown in general formula (1) and compound (B) shown in general formula (2).

[0025] The compound (A) shown in general formula (1) can be obtained by reacting the diisocyanate compound shown in general formula (4) with the compound shown in formula (5) (hereinafter also referred to as "glycerol carbonate (GC)").

[0026] (In general formulas (1) and (4), R1 represents a hydrocarbon group containing a ring structure with 6 to 16 carbon atoms).

[0027] The polyhydroxylamine carbamate resin proposed in Patent Document 2 is manufactured using a cyclic carbonate compound represented by the following general formula (X). This cyclic carbonate compound can be obtained by reacting a corresponding epoxy compound with carbon dioxide (CO2). However, when reacting the epoxy compound with carbon dioxide, catalysts such as salts or halogens and organic solvents such as dimethylformamide must be used, and these catalysts or organic solvents must be removed after the reaction. Therefore, the reaction of epoxy compounds with carbon dioxide presents the problem of being prone to long-term and complex reactions.

[0028] (In the general formula (X), R represents a divalent organic group).

[0029] In contrast, the diisocyanate compound of general formula (4) and the compound of formula (5) above (glycerol carbonate (GC)) can react without solvents and do not require catalysts such as salts or halogens. Therefore, compared with the cyclic carbonate compound of general formula (X), the compound (A) of general formula (1) (hereinafter also referred to as "bicyclic carbonate monomer (DCM)") can be manufactured in a shorter time with a simpler reaction procedure. Furthermore, the aqueous dispersion of the polyhydroxycarbamate resin of this embodiment containing the compound (A) (bicyclic carbonate monomer (DCM)) can form a film layer with lower oxygen permeability and better gas barrier properties compared with the conventional aqueous dispersion of polyhydroxycarbamate resin containing the cyclic carbonate compound of general formula (X). Furthermore, by using an aqueous dispersion of the polyurethane resin of this embodiment containing compound (A) (DCM), a film layer with excellent adhesion to metals or metal oxides such as metal vapor-deposited layers can be formed, and a gas-barrier film with excellent gas barrier properties and excellent adhesion to metals and metal oxides can be manufactured. Moreover, "metal oxide" includes oxides of half-metals such as silicon (Si).

[0030] In general formula (1), R1 represents a hydrocarbon group with 6 to 16 carbon atoms containing a ring structure, preferably a hydrocarbon group with 5 to 13 carbon atoms. The ring structure can be either an aliphatic ring structure or an aromatic ring structure. When the hydrocarbon group does not contain a ring structure, it is difficult to form the target polyhydroxylamine ester resin or to form an aqueous dispersion.

[0031] The compound (B) shown in general formula (2) can be obtained by reacting the diamine compound shown in general formula (6) with the diglycidyl compound shown in formula (7).

[0032] (In general formulas (2) and (6), R3 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms; in general formulas (2) and (7), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms).

[0033] In general formulas (2) and (6), the aliphatic hydrocarbon group represented by R3 preferably has 3 to 10 carbon atoms, more preferably 4 to 9. In general formulas (2) and (6), the alicyclic hydrocarbon group represented by R3 preferably has 5 to 12 carbon atoms, more preferably 6 to 9. In general formulas (2) and (6), the aromatic hydrocarbon group represented by R3 preferably has 6 to 15 carbon atoms, more preferably 6 to 12.

[0034] In general formulas (2) and (7), the aliphatic hydrocarbon group represented by R2 preferably has 3 to 10 carbon atoms, more preferably 4 to 9. In general formulas (2) and (7), the alicyclic hydrocarbon group represented by R2 preferably has 5 to 12 carbon atoms, more preferably 6 to 9. In general formulas (2) and (7), the aromatic hydrocarbon group represented by R2 preferably has 6 to 15 carbon atoms, more preferably 6 to 12.

[0035] By reacting an anhydride with a cyclic anhydride structure with a polymer obtained by polyaddition reaction of compound (A) and compound (B), a polyhydroxycarboxylate resin with carboxyl groups can be obtained. Furthermore, by neutralizing the carboxyl groups of the obtained polyhydroxycarboxylate resin with alkali and then mixing it with water for phase inversion emulsification, an aqueous dispersion of the polyhydroxycarboxylate resin of the present embodiment containing the structural part shown in the general formula (3) below can be obtained.

[0036] (In general formula (3), R1 is synonymous with R1 in general formula (1), and R2 and R3 are synonymous with R2 and R3 in general formula (2), respectively; X represents an aliphatic hydrocarbon group with 1 to 10 carbon atoms or an aromatic hydrocarbon group with 6 to 10 carbon atoms that may also contain oxygen or nitrogen atoms; M represents a hydrogen atom or a relative ion used to form a salt structure).

[0037] In general formula (3), the aliphatic hydrocarbon group represented by X preferably has 2 to 8 carbons, more preferably 2 to 5. In general formula (3), the aromatic hydrocarbon group represented by X preferably has 6 to 8 carbons.

[0038] As an anhydride having a cyclic anhydride structure (hereinafter also referred to as "cyclic anhydride"), compounds having multiple carboxyl groups whose carboxyl groups are formed by intramolecular dehydration condensation can be used. Specific examples of cyclic anhydrides include aliphatic anhydrides such as succinic anhydride, isocrine anhydride, maleic anhydride, calonic anhydride, citrine anhydride, glutaric anhydride, diethylene glycol anhydride, and 1,2,3,4-butanetetracarboxylic anhydride; aromatic anhydrides such as phthalic acid, trimellitic anhydride, 1,2-naphthalenedicarboxylic anhydride, and pyromellitic anhydride; and alicyclic anhydrides such as 1,1-cyclohexanediacetic anhydride, 1-cyclohexene-1,2-dicarboxylic anhydride, 1,1-cyclopentanediacetic anhydride, and 5-norphene-2,3-dicarboxylic anhydride; etc. Furthermore, when using polyvalent anhydrides such as pyromellitic anhydride, there are cases where a structure consisting of two or more cross-linked polyurethane groups is formed. That is, polyurethane resin is a structure containing two or more cross-linked polyurethane chains.

[0039] The amount of carboxyl groups (carboxylic acid groups) in the polyurethane resin and the particle size of the polyurethane resin (resin particles) in the aqueous dispersion are considered to be almost proportional. The more carboxyl groups, the smaller the particle size. Conversely, the fewer carboxyl groups, the larger the particle size; when this size exceeds a certain threshold, the dispersion (emulsion) becomes unstable. For this reason, the average particle size of the polyurethane resin (resin particles) contained in the aqueous dispersion of this embodiment is 1-10,000 nm, preferably 5-5,000 nm, and more preferably 8-2,000 nm. The average particle size in this specification is the value of the cumulative 50% particle diameter (median diameter; D50) in the volumetric particle size distribution measured by dynamic light scattering.

[0040] The amount of carboxyl groups in the polyurethane resin is preferably such that the acid value of the polyurethane resin is 15-60 mg KOH / g, more preferably 25-58 mg KOH / g. If the acid value of the polyurethane resin is above 15 mg KOH / g, the polyurethane resin is easily emulsified in water. On the other hand, if the acid value of the polyurethane resin is below 60 mg KOH / g, the film obtained from the aqueous dispersion of the polyurethane resin has good water resistance, and the addition of film-forming aids can be easily omitted during high-speed coating and drying in actual production machines.

[0041] The dispersion (emulsification) stability of polyurethane resins is also affected by the molecular weight of the resin. Therefore, the preferred weight-average molecular weight of polyurethane resins is 10,000–150,000, more preferably 30,000–130,000, and particularly preferably 50,000–120,000. The weight-average molecular weight in this specification is a value converted from polystyrene determined by gel permeation chromatography (GPC).

[0042] The aqueous dispersion system of this embodiment contains water as a dispersion medium. The dispersion medium does not need to consist of only water. That is, the dispersion medium can be water alone, or it can contain water and a hydrophilic solvent.

[0043] The content (solids) of polyurethane resin in the aqueous dispersion can be adjusted appropriately according to the application. Specifically, the content of polyurethane resin in the aqueous dispersion is based on the total mass of the aqueous dispersion, and is preferably about 10 to 50% by mass.

[0044] Aqueous dispersion systems, to meet the necessary characteristics during processing (use), can be used after the addition of various additives, or may contain various additives. Examples of additives include rheology modifiers. Rheology modifiers can also include starch-based thickeners, inorganic fillers (mica, clay, silicon dioxide, etc.), and cellulose nanofibers. In particular, by incorporating rheology modifiers containing minerals such as clay and mica into the aqueous dispersion, the gas barrier properties of the resulting film can be further improved. Furthermore, "minerals" include artificial minerals such as synthetic mica. Additives other than rheology modifiers include antioxidants, light stabilizers, and ultraviolet absorbers.

[0045] The aqueous dispersion can be used with a curing agent that is soluble or dispersible in water. Preferably, the curing agent is one that cross-links with the hydroxyl or carboxylic acid groups of the polyurethane resin in the aqueous dispersion to form a cross-linked film. Examples of such curing agents include polyisocyanates, block isocyanates, epoxy compounds, metal chelates such as aluminum or titanium, melamine resins, aldehyde compounds, and carbodiimide compounds.

[0046] Polyhydroxylamine resin has hydroxyl groups in the repeating unit (i) that is part of the basic structure. Therefore, by using an aqueous dispersion of polyhydroxylamine resin, a film layer with excellent gas barrier properties can be formed. Furthermore, as mentioned above, since the aqueous dispersion of this embodiment contains polyhydroxylamine resin manufactured using compound (A) (DCM) of general formula (1), a film layer with even better adhesion to metals such as metal vapor-deposited layers can be formed.

[0047] The gas barrier properties of the coating (coating layer) are due to the presence of hydroxyl groups in the structure of the polyurethane resin. The degree of gas barrier properties of the coating depends on the amount of hydroxyl groups in the structure of the polyurethane resin. On the other hand, the amount of hydroxyl groups in the structure of the polyurethane resin also affects the hardness and adhesion of the coating. From these points of view, the hydroxyl value of the polyurethane resin is preferably 150~250 mgKOH / g. From the viewpoint of easily obtaining a coating with better gas barrier properties, the above-mentioned hydroxyl value is more preferably 165 mgKOH / g or higher, and preferably 170 mgKOH / g or higher. On the other hand, from the viewpoint of easily obtaining a coating with moderate hardness and good adhesion even when drying in an actual machine (where it becomes difficult to dry at a sufficiently high temperature), the above-mentioned hydroxyl value is more preferably 230 mgKOH / g or lower, and preferably 215 mgKOH / g or lower.

[0048] The aqueous dispersion of this embodiment contains a polyhydroxycarboxylate resin with carboxyl groups at specific positions in its molecular structure, thus exhibiting excellent dispersion stability and long-term storage capability. Furthermore, due to the excellent film-forming properties of the aqueous dispersion of this embodiment, a film can still be formed even under low-temperature drying conditions, such as around 40°C. Therefore, because of its excellent film-forming properties, the polyhydroxycarboxylate resin in the aqueous dispersion is suitable for use as a film-forming resin in water-based coatings or as a binder resin in coating agents.

[0049] Furthermore, since the aqueous dispersion of this embodiment contains a polyhydroxylamine resin with hydroxyl groups at specific positions in its molecular structure, it can form a film exhibiting good gas barrier properties. Moreover, since the amount of hydroxyl groups in the polyhydroxylamine resin can be controlled, the performance of the film formed using this aqueous dispersion can be made equivalent to that of films formed using conventional solvent-based polyhydroxylamine solutions.

[0050] <Method for manufacturing aqueous dispersions of polyurethane resins> The above-mentioned aqueous dispersion can be manufactured by the manufacturing method shown below. That is, one embodiment of the manufacturing method of the polyurethane resin aqueous dispersion of the present invention (hereinafter also referred to as the "method of manufacturing aqueous dispersion") is a method for manufacturing the above-mentioned aqueous dispersion, which includes the steps shown below. Hereinafter, the manufacturing method of the aqueous dispersion of the present invention will be described in detail. [1] The step of reacting the diisocyanate compound of the following general formula (4) with the compound of the following formula (5) to obtain compound (A) (step [1]) [2] The step of reacting the diamine compound of the following general formula (6) with the diglycidyl compound of the following general formula (7) to obtain a reactant containing compound (B) (step [2]) [3] The step of reacting the obtained compound (A) with the reactants to obtain the polymer (step [3]) [4] The step of reacting the obtained polymer with an anhydride having a cyclic anhydride structure to obtain a polyhydroxylamine formate resin having a carboxyl group (step [4])

[0051] (In the above general formula (4), R1 represents a hydrocarbon group with 6 to 16 carbons containing a ring structure. In the above general formula (6), R3 represents an aliphatic hydrocarbon group with 1 to 12 carbons, an alicyclic hydrocarbon group with 4 to 16 carbons, or an aromatic hydrocarbon group with 6 to 18 carbons. In the above general formula (7), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbons, an alicyclic hydrocarbon group with 4 to 16 carbons, or an aromatic hydrocarbon group with 6 to 18 carbons.)

[0052] In step [1], the diisocyanate compound of general formula (4) is reacted with the compound (GC) of formula (5). Compound (A) is obtained thereby. As the diisocyanate compound, a compound having a hydrocarbon group with 6 to 16 carbon atoms containing a ring structure is used. If a diisocyanate compound without a hydrocarbon group containing a ring structure is used, it is difficult to form the target polyhydroxylamine ester resin or to form an aqueous dispersion.

[0053] Examples of diisocyanate compounds include alicyclic diisocyanates such as bis(methyl)cyclohexane (HXDI), isophorone diisocyanate (IPDI), and 4,4'-methylene-bis(cyclohexane isocyanate) (HMDI); aromatic diisocyanates such as m-xylyl diisocyanate (XDI), toluene-2,4-diisocyanate (TDI), 1,5-naphthalene diisocyanate (NDI), 1,4-phenyl diisocyanate (PPDI), 2,4-diphenylmethane diisocyanate (MDI), and 4,4-diphenylmethane diisocyanate (MDI); etc.

[0054] The amount of glycerol carbonate (GC) reacted is preferably 1.5 mol or more, more preferably 1.8 mol or more, and especially preferably 2.0 mol or more, relative to 1 mol of the diisocyanate compound. The diisocyanate compound and GC are reacted, for example, by mixing the diisocyanate compound and GC and reacting at a temperature of 60-120°C for 4-10 hours. A catalyst commonly used in the synthesis of ethyl carbamate can be used during the reaction. Furthermore, the diisocyanate compound and GC can react without solvent or in the presence of an organic solvent. Suitable organic solvents include tetrahydrofuran, dimethyl ether, dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide, ethylene glycol dimethyl ether, dioxolane, butyl acetate, propyl acetate, methyl ethyl ketone, and diethylene glycol dimethyl ether.

[0055] In step [2], the diamine compound of general formula (6) is reacted with the diglycidyl compound of general formula (7). Compound (B) is formed thereby, and a reactant containing compound (B) is obtained. As a diamine compound, any compound having at least two amino groups in one molecule may also be used. Specific examples of diamine compounds include aliphatic polyamines such as ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane (also known as hexamethylenediamine), 1,8-diaminooctane, 1,10-diaminodecane, and 1,12-diaminododecane; alicyclic polyamines such as isophorone diamine, norphenyl diamine, 1,6-cyclohexane diamine, and piperazine; aromatic polyamines such as o-, m-, or p-phenylenediamine, o-, m-, or p-phenylenediamine, diaminodiphenylmethane, and 2,5-diaminopyridine; etc.

[0056] As a diglycidyl compound, any compound having at least two glycidyl groups in one molecule may be used. Specific examples of diglycidyl compounds include, for instance, aromatic diglycidyl ethers such as resorcinol diglycidyl ether, bisphenol A diglycidyl ether, phthalic acid diglycidyl ester, and 1,4-dihydro-9,10-bis(glycidyloxy)anthracene; aliphatic diglycidyl ethers such as ethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, and 1,4-dibutanol diglycidyl ether; alicyclic diglycidyl ethers such as hydrogenated bisphenol A diglycidyl ether and 1,4-cyclohexanediethanol diglycidyl ether; etc.

[0057] Preferably, the diamine compound and the diglycidyl compound react under conditions where the ratio of amino groups to glycidyl groups is 4 / 1 or higher to obtain the reactant; more preferably, the reaction is carried out under conditions where the ratio of amino groups to glycidyl groups is 5 / 1 or higher to obtain the reactant. By reacting the diamine compound and the diglycidyl compound in the above ratio, a compound (B) with amino groups at both ends can be formed, and a reactant containing unreacted diamine compound can be obtained.

[0058] The diamine compound and the diglycidyl compound can be reacted, for example, by mixing the diamine compound and the diglycidyl compound and reacting at a temperature of 30-60°C for 5-20 hours. Alternatively, the diamine compound and the diglycidyl compound can react without a solvent or in the presence of an organic solvent. Examples of organic solvents include those used in step [1].

[0059] Step [3] is a step of performing a polyaddition reaction between the compound (A) obtained in step [1] and the reactant containing compound (B) obtained in step [2] to obtain a polymer. Preferably, the polyaddition reaction between compound (A) and the reactant is performed in such a manner that the stoichiometric ratio (amine group / five-membered cyclic carbonate structure) of the amino groups in compound (B) is in the range of 1.1 to 1.3 relative to the five-membered cyclic carbonate structure in compound (A). The compound (A) and the reactant containing compound (B) can be, for example, by mixing the compound (A) and the reactant and reacting at a temperature of 40 to 200°C for 4 to 24 hours. The compound (A) and the reactant can react without solvent or in the presence of an organic solvent. Examples of organic solvents that are the same as those used in step [1] can be used.

[0060] In step [4], the polymer obtained in step [3] is reacted with an anhydride having a cyclic anhydride structure. In this way, the amine groups in the polymer react with the anhydride to obtain a polyhydroxylamine formate resin having carboxyl groups. Since the reaction between the amine groups and the anhydride is very fast, it is preferable to react the polymer with the anhydride at a temperature of -10 to 40°C. From the viewpoint of achieving a state that is easy to stir while suppressing viscosity increase, the above temperature is preferably set to 5°C or higher, more preferably 10°C or higher, and especially preferably 15°C or higher. On the other hand, from the viewpoint of suppressing gelation caused by the three-dimensionalization of side reactions, the above temperature is preferably set to 35°C or lower, and especially preferably 30°C or lower. The amount of anhydride used is preferably such that the equivalent ratio of anhydride groups to amine groups in the polymer (anhydride groups / amine groups) is 0.8 to 1.0.

[0061] The acid value of the obtained polyhydroxylamine carbamate resin can be controlled by adjusting the types of compounds (A), (B), and anhydrides, or the ratio of compounds (A) to (B) (equivalent ratio of amino groups to five-membered cyclic carbonate structures).

[0062] The carboxyl group introduced by the acid anhydride can also be in its original state. In this case, a polyhydroxylamine carboxylate resin with repeating unit (i) of the structural part shown in general formula (4) where M is a hydrogen atom in the above general formula (3) can be obtained as the basic structure. In the case of polyhydroxylamine carboxylate resin having a carboxyl group (COOH) in this state, this carboxyl group can also be used in crosslinking or modification reactions.

[0063] In obtaining an aqueous dispersion of polyhydroxycarbamate resin, it is preferable to neutralize the carboxyl groups of the polyhydroxycarbamate resin in order to promote ionization in water. That is, the method for manufacturing the aqueous dispersion of this embodiment preferably further includes the step of neutralizing the carboxyl groups of the polyhydroxycarbamate resin obtained in step [4] with alkali and then mixing it with water for phase inversion emulsification (step [5]). At this time, a portion of the carboxyl groups may also be neutralized, but it is more preferable to neutralize all the carboxyl groups and make the polyhydroxycarbamate resin into a neutralized salt form. It is preferable to make all the carboxyl groups into a neutralized salt by using an equimolar amount of alkali or an excess amount of about 1 to 10% of the carboxyl groups.

[0064] Examples of bases include organic amines such as ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyldiethanolamine, monoethanolamine, dimethylethanolamine, diethylethanolamine, succinyl phosphate, N-methylsuccinyl phosphate, and 2-amino-2-methyl-1-propanol; alkali metals such as lithium, potassium, and sodium; and inorganic bases such as sodium hydroxide, potassium hydroxide, calcium hydroxide, potassium hydroxide, and ammonia.

[0065] In step [5], the carboxyl groups of the polyhydroxycarbamate resin are neutralized with alkali and then mixed with water for phase inversion emulsification. More specifically, an O / W type emulsion can be obtained by slowly adding water to the alkali-neutralized solution to induce phase inversion. The amount of water is preferably adjusted according to the chemical structure of the polyhydroxycarbamate resin, the type of organic solvent, the resin concentration in the solution, and the viscosity of the solution. Specifically, it is preferable to use about 50 to 200 parts by mass of water per 100 parts by mass of the solution for phase inversion. There is no need to heat the solution during phase inversion. In order to reduce the solubility of water in the resin solution before phase inversion, it is more efficient and preferable to carry out the process at a temperature of about 10 to 30°C.

[0066] Furthermore, it is preferable to heat the O / W emulsion obtained by phase inversion emulsification under reduced pressure. This causes the organic solvents used in the manufacture of the polyurethane resin to evaporate, resulting in an aqueous dispersion in which only the resin component is dispersed in water. The heating and reduced pressure conditions vary depending on the boiling point of the evaporated organic solvent; conditions where water does not evaporate first are preferred, and are preferably adjusted within a range of approximately 50–300 Torr and 20–70°C.

[0067] <Gas Barrier Film> Since the film formed using the above-described aqueous dispersion exhibits good gas barrier properties, it can be used in gas barrier films. Specifically, one embodiment of the gas barrier film of the present invention comprises: a substrate film; and a coating layer disposed on at least one side of the substrate film. Furthermore, this coating layer contains a polyurethane resin constituting the above-described aqueous dispersion. The coating layer constituting this gas barrier film can be formed using an aqueous dispersion of the above-described polyurethane resin.

[0068] Preferred applications of gas barrier films include, for example, packaging materials. For better suitability as a packaging material, the oxygen permeability of the gas barrier film, under conditions of 23°C and 90% relative humidity, is preferably below 50 mL / m²·day·atm. Furthermore, the film layer preferably achieves the aforementioned oxygen permeability range within a thickness of 0.1 to 20 μm. The film layer thickness is more preferably 0.1 to 15 μm, and particularly preferably 0.1 to 10 μm.

[0069] As the base film, for example, plastic films commonly used in the field of packaging materials suitable for use as gas barrier films can be used. Materials for the base film include, for example, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polylactic acid; polyolefin resins such as low-density polyethylene, high-density polyethylene, and polypropylene; cellulose resins; polystyrene resins such as polystyrene; ethylene-vinyl acetate copolymers such as ethylene-vinyl acetate copolymers; ethylene-vinyl alcohol copolymers; polyamide resins such as nylon 6 and nylon 66; polycarbonate resins; acrylic resins; polyimide; polyvinyl chloride resins; and other copolymer resins; etc. Furthermore, these resin materials may appropriately contain various additives such as antistatic agents, ultraviolet absorbers, plasticizers, lubricants, and colorants, as needed.

[0070] Furthermore, the film layer formed using the aforementioned aqueous dispersion exhibits excellent adhesion to metals or metal oxides, such as metal vapor-deposited layers. Therefore, it is preferable to use a laminated film having a metal layer, such as a metal vapor-deposited layer, on at least one surface of a film formed from the aforementioned resin materials as the substrate film. This allows for the creation of a barrier film with excellent adhesion to the metal layer while simultaneously having a metal layer, such as a metal vapor-deposited layer. Examples of metals constituting the metal layer include aluminum, titanium, copper, silver, and nickel. Examples of metal oxides include oxides of half-metals such as silicon, such as aluminum oxide, silicon dioxide, titanium oxide, and zinc peroxide.

[0071] By coating at least one side of a substrate film with the aforementioned aqueous dispersion, or a coating agent (paint, etc.) containing an aqueous dispersion, a film layer can be formed. A coating machine can be used for this coating process. Examples of coating machines include gravure coating machines, blade coating machines, reverse coating machines, bar coating machines, spray coating machines, and slot coating machines.

[0072] After coating a substrate film with an aqueous dispersion or coating agent, it is dried, thereby allowing water and other substances to evaporate and form a film layer. The aqueous dispersion used to form the film layer has excellent film-forming properties, and a film layer can still be formed even under low-temperature drying conditions, such as below 60°C, preferably below 50°C, and especially below 40°C. The drying temperature for forming the film layer is preferably set to 25~95°C, more preferably 30~90°C, and especially preferably 40~80°C. [Example]

[0073] The present invention will be specifically described below with reference to the embodiments, but the present invention is not limited to these embodiments. Furthermore, the terms "parts" and "%" in the embodiments and comparative examples are, without particular limitation, mass references.

[0074] Synthesis of Bicyclic Carbonates (Synthesis example 1) In a reaction vessel equipped with a stirrer, thermometer, reflux condenser, and vacuum distillation apparatus, 37.86 parts (0.32 mol) of glycerol carbonate (GC) and 76.0 parts (THF) of tetrahydrofuran were added. After heating to 50°C, 31.13 parts (0.16 mol) of bis(isocyanomethyl)cyclohexane (HXDI) were added with stirring, while monitoring for heat generation. 0.002 parts of bismuth 2-ethylhexanoate (2EHBi) were further added, and the reaction was carried out for 1 hour. FT-IR analysis (trade name "FT-720", manufactured by Horiba Seisakusho) was performed, and the reaction was considered complete when the absorption peak of the isocyanate group (NCO) disappeared. THF was removed under vacuum, and the temperature was raised to 100°C, then maintained at 15 mmHg for 15 minutes. This yielded a colorless, transparent, viscous liquid, a bicyclic carbonate (DCM-1) as shown in formula (1-1).

[0075]

[0076] (Synthesis Examples 2~6) Except for using the types and amounts (mol) of the components shown in Table 1, the rest was the same as in Synthesis Example 1 above, yielding bicyclic carbonates (DCM-2~6). The meanings of the abbreviations in Table 1 are as follows. • HXDI: Bis(isocyanomethyl)cyclohexane • XDI: m-xylene diisocyanate • TDI: Toluene-2,4-diisocyanate •IPDI: Isophorone diisocyanate • HMDI: 4,4'-methylene-bis(cyclohexyl isocyanate) HDI: Hexamethylene diisocyanate ‧GC: Glyceryl carbonate

[0077] [Table 1] Synthesis example 1 2 3 4 5 6 Bicyclic carbonates DCM-1 DCM-2 DCM-3 DCM-4 DCM-5 DCM-6 diisocyanate Compound (mol) HXDI 1 XDI 1 TDI 1 IPDI 1 HMDI 1 HDI 1 GC (mol) 2 2 2 2 2 2

[0078] (Synthesis Example 7) In a reaction vessel equipped with a stirrer, thermometer, gas inlet tube, and reflux cooling tube, 11.32 parts of bisphenol A diglycidyl ether (BGE) (trade name "Epotote YD-128", manufactured by NIPPON STEEL Chemical & Material Co., Ltd.) with an epoxy equivalent of 187 g / eq and 8.69 parts of N,N-dimethylformamide (DMF) were added. After heating to 60°C, 2.76 parts of 5% LiBr were added. After heating to 100°C, the reaction was carried out by CO2 bubbling (0.1 L / min) for 10 hours. At 70°C, 45.28 parts of isopropanol (IPA) were added. The precipitated white precipitate was filtered and dried at 100°C for 1 hour using a dryer. This yielded a white powder of bicyclic carbonate (DCM-7) as shown in formula (Y).

[0079]

[0080] (Synthesis Example 8) In a reaction vessel equipped with a stirrer, thermometer, gas inlet pipe, and reflux cooling pipe, 54.68 parts of hydroquinone diglycidyl ether (RGE) with an epoxy equivalent of 117 g / eq and 17.52 parts of DMF were added. After heating to 60°C, 0.65 parts of 5% LiBr2 were added. After heating to 100°C, CO2 (0.1 L / min) was bubbled to allow the reaction to proceed for 10 hours. The DMF was removed using an evaporator, yielding a yellow viscous liquid, the following formula (Z), a bicyclic carbonate (DCM-8).

[0081]

[0082] <Preparation of Resin Solution> (Manufacturing Example 1) 27.24 parts (0.20 mol) of m-phenylenediamine (MXDA) and 15.30 parts of THF were added to a separating flask. 8.46 parts (0.036 mol) of resorcinol diglycidyl ether (RGE) were added with stirring, and the mixture was reacted at 40°C for approximately 6 hours to obtain the reactant. 51.0 parts (70% solids) of the obtained reactant were added to 68.99 parts (0.16 mol) of DCM-1 obtained in Synthesis Example 1 and 32.98 parts of THF. The mixture was stirred at 130 rpm and heated to 65°C for 10 hours. FT-IR analysis was performed, and when the absorption peak (1,800 cm⁻¹) of the cyclic carbonate from the carbonyl group disappeared, 64.37 parts of THF and 22.53 parts of water were added for dilution. 7.07 parts of maleic anhydride (MAA) were added with stirring at a temperature below 30°C. FT-IR analysis confirmed the disappearance of the anhydride absorption peak (1,760 cm⁻¹) before adding 0.87 parts of pyromellitic dianhydride (PMDA). FT-IR analysis confirmed the reaction ended after the anhydride absorption peak (1,760 cm⁻¹) disappeared. As described above, a polyurethane resin solution (RS-1) representing the resin solution before phase inversion emulsification was obtained.

[0083] (Manufacturing Examples 2-8, Comparative Manufacturing Examples 1-3) Except for using the types and amounts (parts) of each component shown in Table 2, the rest was the same as in Manufacturing Example 1 above, and solutions of polyhydroxycarbamate resin (RS-2~10) were obtained. Furthermore, in Comparative Manufacturing Example 3, gelation occurred and precipitation occurred during the reaction of DCM with the diamine compound, making it impossible to produce resin (resin solution RS-11). The meanings of the abbreviations in Table 2 are as follows. • RGE: Resorcinol diglycidyl ether • BGE: Bisphenol A diglycidyl ether ‧MXDA:m-phenylenediamine HMD: Hexamethylenediamine •MAA: maleic anhydride •SA: Succinic anhydride •PMDA: Pyromellitic dianhydride

[0084] <Resin Analysis> (Acid value, hydroxyl value) The content of each functional group per 1g of resin was determined by titration according to JIS K1557, expressed in mg equivalents of KOH. The unit is mgKOH / g. The results are shown in Table 2.

[0085] (weight average molecular weight) The weight-average molecular weight of polyurethane resin converted from polystyrene was determined by gel permeation chromatography (GPC) using dimethylformamide (DMF) as the mobile phase. A GPC apparatus (trade name "GPC-8220") and column (trade name "Super AW2500+AW3000+AW4000+AW5000") manufactured by Tosoh Corporation were used for the determination. The results are shown in Table 2.

[0086] [Table 2] Manufacturing example Comparative manufacturing examples 1 2 3 4 5 6 7 8 1 2 3 resin solution RS-1 RS-2 RS-3 RS-4 RS-5 RS-6 RS-7 RS-8 RS-9 RS-10 RS-11 DCM (share) DCM-1 68.99 67.93 68.64 73.07 DCM-2 65.85 DCM-3 60.00 DCM-4 72.79 DCM-5 77.76 DCM-7 70.78 DCM-8 55.70 DCM-6 75.06 Second shrinkage glycerol Compound (parts) RGE 8.46 9.45 6.10 9.53 11.62 8.84 9.33 4.87 9.31 BGE 14.37 15.12 diamine Compound (parts) MXDA 27.24 27.24 27.24 27.24 27.24 27.24 27.24 27.24 27.24 31.34 HMD 23.20 acid anhydride (share) MAA 7.07 7.46 7.92 7.98 9.74 7.41 7.82 7.84 4.08 7.80 SA 5.22 PMDA 0.87 0.87 0.87 0.87 0.87 0.87 0.87 0.44 0.87 1.00 Acid value (mgKOH / g) 40 40 40 30 45 55 40 40 40 30 - Hydroxyl value (mgKOH / g) 196 187 198 195 197 201 188 179 190 240 - Weight average molecular weight 110,000 100,000 75,000 105,000 90,000 95,000 80,000 90,000 102,000 130,000 -

[0087] <Manufacturing of Aqueous Dispersions> (Example 1) 2.43 parts of 25% ammonia were added dropwise to 100 parts of the resin solution RS-1 obtained in Example 1 (containing 45.46% NV and 9.09 parts water). Water was added dropwise further to reduce the resin solids content to 30% after THF removal, and the mixture was degassed until the odor of THF disappeared, resulting in an aqueous dispersion of polyurethane resin (WD-1).

[0088] (Examples 2-8, Comparative Examples 1 and 2) Except for the components shown in Table 3, the process was the same as in Example 1 above, and an aqueous dispersion of polyhydroxycarbamate resin (WD-2~10) was obtained.

[0089] <Analysis of Aqueous Dispersions> (Average particle diameter) The cumulative 50% particle diameter (median diameter; D50) of the volumetric particle size distribution of resin particles in an aqueous dispersion was measured using a dynamic light scattering particle size distribution measuring device (trade name "Nanotrac UPA-EX150", manufactured by Nikkiso Corporation) as the average particle diameter. The results are shown in Table 3.

[0090] (Viscosity) The viscosity of the aqueous dispersion was measured using a BM type viscometer (Tokyo Keiki Manufacturing Co., Ltd.) under the conditions of rotor No. 2 / 60rpm / 25℃.

[0091] [Table 3] Example Comparative example 1 2 3 4 5 6 7 8 1 2 Aqueous dispersion WD-1 WD-2 WD-3 WD-4 WD-5 WD-6 WD-7 WD-8 WD-9 WD-10 Types of resin solutions RS-1 RS-2 RS-3 RS-4 RS-5 RS-6 RS-7 RS-8 RS-9 RS-10 Polyhydroxycarbamate resin Content (solids (%)) 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 Average particle diameter (nm) 20.9 15.1 61.0 23.2 14.1 177.1 22.9 10.7 13.5 20.0 Viscosity (mPa·s) 19.6 50.0 8.5 22.5 25.0 17.5 13.0 20.0 15.0 10.0

[0092] <Manufacturing of laminated thin films (1)> (Examples 9-16, Comparative Examples 3 and 4) The manufactured aqueous dispersions (WD-1~10) were coated onto a substrate film using a bar coater to achieve a dry film thickness of 10 μm. The film was then dried in an oven at 80°C for 10 minutes to form a coating layer. This process created a laminated film (gas barrier film) consisting of a substrate film and a coating layer disposed on one surface of the substrate film. The substrate film used was a 25 μm thick biaxially oriented polyester (PET) film (trade name "Lumirror #25-T60", manufactured by Toray Industries, Inc.; measured oxygen permeability: 51.77 mL / m²·day·atm).

[0093] <Evaluation> (Gas barrier properties (oxygen permeability)) For the laminated films, according to JIS K7126:2006, the oxygen transmission rate was measured under constant temperature and humidity conditions of 23°C and 65% relative humidity. The results are shown in Table 4. An oxygen transmission rate measuring device (trade name "OX-TRAN 2 / 21ML", manufactured by MOCON) was used for the measurement. A lower oxygen transmission rate indicates better gas barrier properties; therefore, oxygen transmission rate was used as an evaluation index for gas barrier properties. Furthermore, the thickness of the coating layer of each laminated film was measured using a precision thickness gauge (manufactured by Ozaki Manufacturing Co., Ltd.), and it was confirmed that all were 10 μm.

[0094] (Adhesion strength) <Production of the Experimental Film> The manufactured aqueous dispersion (WD-1~10) was coated onto a substrate film using a rod coater to achieve a dry film thickness of 2 μm. The film was then dried in an oven at 80°C for 2 minutes to form a coating layer. An adhesive mixture of 9 parts of "SEIKABOND A601" (manufactured by Dainippon Seika Kogyo Co., Ltd.), 1 part of "SEIKABOND C-76" (manufactured by Dainippon Seika Kogyo Co., Ltd.), and 10 parts of ethyl acetate was applied to the formed coating layer to a thickness of 4 μm and dried in a hot air dryer for 90 seconds to form an adhesive layer. A 60 μm thick CPP film (trade name "PYLEN film CT P1146", manufactured by Toyobo Co., Ltd.) was then stacked on the formed adhesive layer and cured at 40°C and 3 kgf / cm² for at least 3 days. This results in a laminated film in which a substrate film, a coating layer, an adhesive layer, and a CPP film are deposited in that order. The substrate film is one of the following three types. • Alumina 1011HG: 12μm thick alumina vapor-deposited PET film, trade name "BARRIALOX Non-coat Type 1011HG", manufactured by Toray Film Processing Co., Ltd. • VmPET: 12μm thick alumina vapor-deposited PET film, trade name "VM-PET1510", manufactured by Toray Film Processing Co., Ltd. • TECHBARRIER LQ: 12μm thick silicon dioxide vapor-deposited PET film, trade name "TECHBARRIER LQ", manufactured by Mitsubishi Chemical Corporation.

[0095] Three test pieces of the obtained laminated film were taken in the transverse direction with dimensions of 15 mm × 200 mm. A 50 mm section was manually peeled off from the end of each test piece. Using a constant-speed elongation tensile testing machine (trade name "Autograph EZ-S-200N" (manufactured by Shimadzu Corporation)), the T-shaped peel was achieved at a tensile speed of 300 mm / min, and the adhesion strength was measured with N=3. The measured adhesion strengths (average values) are shown in Table 4.

[0096] [Table 4] Example Comparative example 9 10 11 12 13 14 15 16 3 4 Types of aqueous dispersions WD-1 WD-2 WD-3 WD-4 WD-5 WD-6 WD-7 WD-8 WD-9 WD-10 Oxygen penetration rate* 11.0 13.5 8.4 14.4 10.8 7.7 25.5 28.9 34.5 10.5 Next intensity (N) Alumina 1011 HG 3.26 (Material broken) 3.32 (Material broken) 3.28 (Material broken) 3.43 (Material broken) 3.08 (Material broken) 2.79 2.63 2.67 2.00 2.10 VmPET 6.85 (Material broken) 6.92 (Material broken) 6.66 (Material broken) 6.80 (Material broken) 3.91 (Material broken) 3.20 3.50 3.10 0.82 0.55 TECHBARRIER LQ 1.56 1.48 1.35 1.44 1.28 1.76 1.35 1.22 0.46 0.41 *: The unit of oxygen penetration rate is "mL･2μm / m2･day･atm", which is the value converted to a thickness of 2μm.

[0097] <Manufacturing of laminated thin films (2)> (Examples 17-19) 100 parts of the solids of the resin in the aqueous dispersion WD-1 obtained in Example 1 were mixed with 5 parts, 10 parts, and 15 parts of synthetic mica (average particle size 6-7 μm) as rheology modifiers, respectively, to obtain mixtures. Except for using the obtained mixtures, the process was the same as in Examples 9-16, Comparative Examples 3 and 4, to prepare a laminated film (gas barrier film) consisting of a substrate film and a coating layer disposed on one surface of the substrate film. Then, the oxygen permeability of the prepared laminated film was measured using the same procedure as described above for "gas barrier (oxygen permeability)". The results are shown in Table 5.

[0098] [Table 5] Example 17 18 19 Types of aqueous dispersions WD-1 WD-1 WD-1 Amount of clay* 5 10 15 Oxygen penetration (mL·2μm / m2·day·atm) 1.65 0.94 0.38 *: Amount (parts) relative to 100 parts of the resin's solids content. (Industrial applicability)

[0099] The aqueous dispersion of the polyhydroxycarbamate resin of the present invention can be used as a material for forming a gas barrier coating layer constituting a gas barrier film.

Claims

1. An aqueous dispersion of a polyhydroxycarbamate resin, comprising water and a polyhydroxycarbamate resin with an average particle size of 1 to 10,000 nm dispersed in the water; the polyhydroxycarbamate resin having a basic structure consisting of a repeating unit (i) formed by polymerizing a compound (A) of general formula (1) and a compound (B) of general formula (2), and then introducing a COOM group after polymerization; the repeating unit (i) having a structural portion of general formula (3); (in general formula (1), R1 represents a hydrocarbon group with 6 to 16 carbon atoms containing a ring structure) (In the above general formula (2), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms, and R3 represents an aliphatic hydrocarbon group with 1 to 12 carbon atoms, an alicyclic hydrocarbon group with 4 to 16 carbon atoms, or an aromatic hydrocarbon group with 6 to 18 carbon atoms.) (In the above general formula (3), R1 is synonymous with R1 in the above general formula (1), and R2 and R3 are synonymous with R2 and R3 in the above general formula (2), respectively; X represents an aliphatic hydrocarbon group with 1 to 10 carbon atoms or an aromatic hydrocarbon group with 6 to 10 carbon atoms that may also contain oxygen or nitrogen atoms; M represents a hydrogen atom or a relative ion used to form a salt structure.) 2. An aqueous dispersion of the polyurethane resin as claimed in claim 1, wherein, The above-mentioned polyhydroxylamine carbamate resin has a weight average molecular weight of 10,000~150,000, an acid value of 15~60 mgKOH / g, and a hydroxyl value of 150~250 mgKOH / g.

3. A method for manufacturing an aqueous dispersion of a polyhydroxycarbamate resin, which is the method for manufacturing an aqueous dispersion of a polyhydroxycarbamate resin according to claim 1 or 2, comprising: a step of reacting a diisocyanate compound of general formula (4) with a compound of general formula (5) to obtain the above compound (A); a step of reacting a diamine compound of general formula (6) with a diglycidyl compound of general formula (7) to obtain a reactant containing the above compound (B); a step of subjecting the obtained above compound (A) to a polyaddition reaction with the above reactant to obtain a polymer; and a step of reacting the obtained polymer with an anhydride having a cyclic anhydride structure to obtain a polyhydroxycarbamate resin having a carboxyl group. (In the above general formula (4), R1 represents a hydrocarbon group with 6 to 16 carbons containing a ring structure; in the above general formula (6), R3 represents an aliphatic hydrocarbon group with 1 to 12 carbons, an alicyclic hydrocarbon group with 4 to 16 carbons, or an aromatic hydrocarbon group with 6 to 18 carbons; in the above general formula (7), R2 represents an aliphatic hydrocarbon group with 1 to 12 carbons, an alicyclic hydrocarbon group with 4 to 16 carbons, or an aromatic hydrocarbon group with 6 to 18 carbons).

4. A method for manufacturing an aqueous dispersion of the polyurethane resin as claimed in claim 3, wherein, The method further includes the step of neutralizing the carboxyl groups of the above-mentioned polyhydroxylamine carboxylate resin with an alkali and then mixing it with water to perform phase inversion emulsification.

5. A method for manufacturing an aqueous dispersion of the polyurethane resin as claimed in claim 3, wherein, The above-mentioned diamine compound and the above-mentioned diglycidyl compound are reacted under conditions where the equivalence ratio of amino groups to glycidyl groups is 4 / 1 or higher, to obtain the above-mentioned reactants.

6. A method for manufacturing an aqueous dispersion of the polyurethane resin as claimed in claim 3, wherein, The aforementioned anhydride is selected from at least one of the groups consisting of maleic anhydride, pyromellitic anhydride, and succinic anhydride.

7. A gas barrier film comprising: a substrate film; and a coating layer disposed on at least one side of the substrate film, comprising a polyhydroxycarbamate resin containing an aqueous dispersion of the polyhydroxycarbamate resin constituting claim 1 or 2.