Aqueous dispersion of polyhydroxyurethane resin, method for producing the same, and gas barrier film

Abstract

The present invention provides an aqueous dispersion of polyhydroxyurethane capable of forming a coating layer with excellent gas barrier properties and adhesion to metals and metal oxides. [Solution] The aqueous dispersion of polyhydroxyurethane resin contains water and a polyhydroxyurethane resin dispersed in water, wherein the polyhydroxyurethane resin has as its basic structure a repeating unit (i) polymerized from a compound (A) represented by the following general formula (1) and a compound (B) obtained from the reaction of a diamine and a diglycidyl ether, and the repeating unit (i) has a structural portion represented by the following general formula (3). TIFF0007863649000025.tif24170 TIFF0007863649000026.tif28170

Description

Technical Field

[0001] The present invention relates to an aqueous dispersion of a polyhydroxyurethane resin, a method for producing the same, and a gas barrier film.

Background Art

[0002] A polyurethane-based resin (polyhydroxyurethane) having both a urethane bond and a hydroxyl group in its chemical structure can be produced by a combination of an epoxy compound, carbon dioxide, and an amine compound used as raw materials. Carbon dioxide used as a raw material is incorporated as a -CO-O- bond into the chemical structure of polyhydroxyurethane, and thus is a resin material worthy of attention from the viewpoint of effective utilization of carbon dioxide, which is a greenhouse gas. In addition, applications that utilize functions derived from hydroxyl groups, which are not present in the structure of general existing polyurethane resins obtained from isocyanate compounds and polyols as raw materials (for example, application to gas barrier films), etc. are also being studied.

[0003] Although polyhydroxyurethane is promising for use in the field of coating agents such as paints, having a hydroxyl group together with a urethane bond in its chemical structure makes its solubility in organic solvents low, and the difficulty in coping with various solvent compositions can be an obstacle to its use. On the other hand, for a polyhydroxyurethane aqueous dispersion obtained by dispersing polyhydroxyurethane in water as disclosed in Patent Document 1, it can be expected to be used in the field of aqueous coating agents such as aqueous paints.

[0004] Patent Document 1 proposes introducing a neutralizable carboxylic acid by half-esterifying the hydroxyl groups and acid anhydride in the polyhydroxyurethane to obtain a polyhydroxyurethane aqueous dispersion. However, because the hydroxyl groups are half-esterified to introduce carboxyl groups, there is a problem in that the dispersion stability of the aqueous dispersion is low due to hydrolysis of the half-ester portion. In addition, there is a problem in that the number of hydroxyl groups is reduced in order to utilize the hydroxyl groups of the polyhydroxyurethane in the reaction, making it difficult to fully utilize the functions derived from the hydroxyl groups.

[0005] In response to this, a technique has been proposed to introduce carboxyl groups into polyhydroxyurethane via amide bonds (Patent Document 2). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2007-297544 [Patent Document 2] Japanese Patent Publication No. 2018-070840 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] According to the technology proposed in Patent Document 2, it was possible to form a coating layer with excellent gas barrier properties and to obtain an aqueous dispersion of polyhydroxyurethane with excellent dispersion stability. However, the adhesion of the formed coating layer to metals such as metal vapor deposition layers was not always good, and there was room for improvement.

[0008] This invention has been made in view of the problems of the prior art, and its objective is to provide an aqueous dispersion of polyhydroxyurethane capable of forming a coating layer with excellent gas barrier properties and adhesion to metals and metal oxides. Furthermore, this invention provides a method for producing this aqueous dispersion of polyhydroxyurethane, and a gas barrier film having a coating layer with excellent gas barrier properties and adhesion to metals and metal oxides. [Means for solving the problem]

[0009] In other words, the present invention provides an aqueous dispersion of polyhydroxyurethane resin as shown below. [1] Contains water and a polyhydroxyurethane resin dispersed in the water, the average particle size of which is 1 to 10,000 nm, wherein the polyhydroxyurethane resin polymerizes a compound (A) represented by the following general formula (1) and a compound (B) represented by the following general formula (2). Furthermore, a COOM group was introduced after polymerization. An aqueous dispersion of polyhydroxyurethane resin, comprising a repeating unit (i) as a basic structure, wherein the repeating unit (i) includes a structural portion represented by the following general formula (3).

[0010] TIFF0007863649000001.tif24170 (In the above general formula (1), R1 represents a hydrocarbon group having 6 to 16 carbon atoms that includes a ring structure)

[0011] TIFF0007863649000002.tif19170 (In the above general formula (2), R2 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and R3 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms)

[0012] TIFF0007863649000003.tif28170(In the above general formula (3), R1 is the same as R1 in the above general formula (1), R2 and R3 are the same as R2 and R3 in the above general formula (2), respectively, X represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, which may contain an oxygen atom or a nitrogen atom, and M is a hydrogen atom or a counterion for forming a salt structure) of show)

[0013] [2] An aqueous dispersion of the polyhydroxyurethane resin according to [1], wherein the polyhydroxyurethane resin has a weight-average molecular weight of 10,000 to 150,000, an acid value of 15 to 60 mgKOH / g, and a hydroxyl value of 150 to 250 mgKOH / g.

[0014] Furthermore, the present invention provides a method for producing the following aqueous dispersion of polyhydroxyurethane resin. [3] A method for producing an aqueous dispersion of polyhydroxyurethane resin as described in [1] or [2] above, comprising: reacting a diisocyanate compound represented by the following general formula (4) with a compound represented by the following formula (5) to obtain compound (A); reacting a diamine compound represented by the following general formula (6) with a diglycidyl compound represented by the following general formula (7) to obtain a reaction product containing compound (B); polyaddition reaction of the obtained compound (A) with the reaction product to obtain a polymer; and Cyclic acid anhydride structure A method for producing an aqueous dispersion of a polyhydroxyurethane resin, comprising the steps of reacting an acid anhydride having a carboxyl group to obtain a polyhydroxyurethane resin having a carboxyl group.

[0015] TIFF0007863649000004.tif51170 (In the above general formula (4), R1 represents a hydrocarbon group having 6 to 16 carbon atoms including a ring structure; in the above general formula (6), R3 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms; in the above general formula (7), R2 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms)

[0016] [4] A method for producing an aqueous dispersion of polyhydroxyurethane resin according to [3], further comprising the step of neutralizing the carboxyl groups of the polyhydroxyurethane resin having carboxyl groups with an alkali, and then mixing it with water to perform phase inversion emulsification. [5] A method for producing an aqueous dispersion of polyhydroxyurethane resin according to [3] or [4], wherein the diamine compound and the diglycidyl compound are reacted under conditions such that the equivalent ratio of amino groups to glycidyl groups is amino group / glycidyl group = 4 / 1 or more, to obtain the reaction product. [6] A method for producing an aqueous dispersion of polyhydroxyurethane resin according to any one of [3] to [5], wherein the acid anhydride is at least one selected from the group consisting of maleic anhydride, pyromellitic anhydride, and succinic anhydride.

[0017] Furthermore, the present invention provides the following gas barrier film. [7] A gas barrier film comprising a base film and a coating layer provided on at least one surface of the base film, the coating layer containing a polyhydroxyurethane resin that constitutes an aqueous dispersion of the polyhydroxyurethane resin described in [1] or [2] above. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide an aqueous dispersion of polyhydroxyurethane capable of forming a coating layer excellent in gas barrier properties and metal / metal oxide adhesion. Further, according to the present invention, it is possible to provide a method for producing the aqueous dispersion of polyhydroxyurethane, and a gas barrier film provided with a coating layer excellent in gas barrier properties and metal / metal oxide adhesion.

Mode for Carrying Out the Invention

[0019] <Aqueous Dispersion of Polyhydroxyurethane> Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. One embodiment of the aqueous dispersion of polyhydroxyurethane (hereinafter, also simply referred to as "aqueous dispersion") of the present invention contains water and a polyhydroxyurethane resin dispersed in water, having an average particle diameter of 1 to 10,000 nm. The polyhydroxyurethane resin is polymerized with a compound (A) represented by the following general formula (1) and a compound (B) represented by the following general formula (2). Furthermore, a COOM group was introduced after polymerization. It contains a repeating unit (i) as a basic structure. And this repeating unit (i) contains a structural part represented by the following general formula (3). Hereinafter, details of the aqueous dispersion of polyhydroxyurethane of the present invention will be described.

[0020] TIFF0007863649000005.tif24170 (In the general formula (1), R1 represents a hydrocarbon group having 6 to 16 carbon atoms containing a ring structure)

[0021] TIFF0007863649000006.tif19170 (In the general formula (2), R2 represents an aliphatic hydrocarbon group having 1 to `12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and R3 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms)

[0022] TIFF0007863649000007.tif28170(In the above general formula (3), R1 is the same as R1 in the above general formula (1), R2 and R3 are the same as R2 and R3 in the above general formula (2), respectively, X represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, which may contain an oxygen atom or a nitrogen atom, and M is a hydrogen atom or a counterion for forming a salt structure) of show)

[0023] In this specification, "group derived from a compound" means a group that was present in the compound or a group derived therefrom. Furthermore, "organic group" means a hydrocarbon group that contains at least a carbon atom and may also contain atoms other than carbon atoms and hydrogen atoms (e.g., oxygen, nitrogen, sulfur, and halogen atoms). This hydrocarbon group may be an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a combination of two or more of these, and may have substituents. The aromatic hydrocarbon group may be a fused ring or a linked ring.

[0024] Polyhydroxyurethane resin is a resin having a repeating unit (i) as its basic structure, which includes a structural part represented by general formula (3). This repeating unit (i) is a polymerization of compound (A) represented by general formula (1) and compound (B) represented by general formula (2). Later, the COOM group was introduced. It is a constituent unit that is formed.

[0025] Compound (A), represented by general formula (1), can be obtained by reacting a diisocyanate compound represented by general formula (4) with a compound represented by formula (5) below (hereinafter also referred to as "glycerin carbonate (GC)").

[0026] TIFF0007863649000008.tif58170 (In general formulas (1) and (4), R1 represents a hydrocarbon group with 6 to 16 carbon atoms that includes a ring structure)

[0027] The polyhydroxyurethane 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 the corresponding epoxy compound with carbon dioxide (CO2). However, when reacting the epoxy compound with carbon dioxide, it is necessary to use catalysts such as salts or halogens, and organic solvents such as dimethylformamide, and these catalysts and organic solvents must be removed after the reaction. For this reason, the reaction of epoxy compounds with carbon dioxide has been plagued by the problem of the process being prolonged and complex.

[0028] TIFF0007863649000009.tif18170 (In the general formula (X), R represents a divalent organic group)

[0029] In contrast, the diisocyanate compound represented by general formula (4) and the compound represented by formula (5) (glycerin carbonate (GC)) can be reacted without solvents, and there is no need to use catalysts such as salts or halogens. For this reason, compound (A) represented by general formula (1) (hereinafter also referred to as "dicyclocarbonate monomer (DCM)") can be produced in a shorter time by a simpler reaction process compared to the cyclic carbonate compound represented by general formula (X). Furthermore, the aqueous dispersion of this embodiment containing polyhydroxyurethane resin produced using compound (A) (dicyclocarbonate monomer (DCM)) can form a coating layer with lower oxygen permeability and even better gas barrier properties compared to conventional aqueous dispersions containing polyhydroxyurethane resin produced using the cyclic carbonate compound represented by general formula (X). Furthermore, by using the aqueous dispersion of this embodiment containing a polyhydroxyurethane resin manufactured using compound (A)(DCM), it is possible to form a coating layer with superior adhesion to metals and metal oxides, such as metal vapor deposition layers, and to manufacture a gas barrier film having a coating layer with excellent gas barrier properties and metal / metal oxide adhesion. Note that "metal oxide" includes oxides of metalloids such as silicon (Si).

[0030] In general formula (1), R1 represents a hydrocarbon group having 6 to 16 carbon atoms and containing a ring structure, preferably a hydrocarbon group having 5 to 13 carbon atoms. The ring structure may be either an aliphatic cyclic structure or an aromatic cyclic structure. If the hydrocarbon group does not contain a ring structure, it becomes difficult to form the desired polyhydroxyurethane resin or to form an aqueous dispersion.

[0031] Compound (B), represented by general formula (2), can be obtained by reacting a diamine compound represented by general formula (6) with a diglycidyl compound represented by formula (7).

[0032] TIFF0007863649000010.tif46170 (In general formulas (2) and (6), R3 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms; in general formulas (2) and (7), R2 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms)

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

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

[0035] A polymer obtained by polyaddition reaction of compound (A) and compound (B) is used. Cyclic acid anhydride structure By reacting an acid anhydride having a carboxyl group, a polyhydroxyurethane resin having a carboxyl group can be obtained. Then, after neutralizing the carboxyl group of the obtained polyhydroxyurethane resin with an alkali, it is mixed with water and subjected to phase inversion emulsification to obtain an aqueous dispersion of the polyhydroxyurethane resin of this embodiment, which contains a structural portion represented by the following general formula (3).

[0036] TIFF0007863649000011.tif28170(In general formula (3), R1 is equivalent to R1 in general formula (1), R2 and R3 are equivalent to R2 and R3 in general formula (2), respectively, X represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, which may contain an oxygen atom or a nitrogen atom, and M is a hydrogen atom or a counterion for forming a salt structure) of show)

[0037] In general formula (3), the number of carbon atoms in the aliphatic hydrocarbon group represented by X is preferably 2 to 8, and more preferably 2 to 5. In general formula (3), the number of carbon atoms in the aromatic hydrocarbon group represented by X is preferably 6 to 8.

[0038] Cyclic acid anhydride structureAs acid anhydrides having multiple carboxyl groups (hereinafter also referred to as "cyclic acid anhydrides"), any compound in which the carboxyl groups are dehydrated and condensed intramolecularly can be used. Specific examples of cyclic acid anhydrides include aliphatic acid anhydrides such as succinic anhydride, itaconic anhydride, maleic anhydride, caronic anhydride, citraconic anhydride, glutaric anhydride, diglycolic anhydride, and 1,2,3,4-butanetetracarboxylic dianhydride; aromatic acid anhydrides such as phthalic acid, trimellitic anhydride, 1,2-naphthalic anhydride, and pyromellitic anhydride; alicyclic acid anhydrides such as 1,1-cyclohexanediacetic anhydride, 1-cyclohexene-1,2-dicarboxylic anhydride, 1,1-cyclopentanediacetic anhydride, and 5-norbornene-2,3-dicarboxylic anhydride; and so on. When polyvalent acid anhydrides such as pyromellitic anhydride are used, a structure in which two or more polyurethane chains are crosslinked may be formed. In other words, polyhydroxyurethane resins include those having a structure in which two or more polyurethane chains are crosslinked.

[0039] The amount of carboxyl groups in the polyhydroxyurethane resin and the particle size of the polyhydroxyurethane resin (resin particles) in the aqueous dispersion are considered to be approximately proportional. The more carboxyl groups there are, the smaller the particle size of the resin particles. On the other hand, the less carboxyl groups there are, the larger the particle size of the resin particles, and beyond a certain size the dispersion (emulsification) becomes unstable. For these reasons, the average particle size of the polyhydroxyurethane resin (resin particles) contained in the aqueous dispersion of this embodiment is 1 to 10,000 nm, preferably 5 to 5,000 nm, and more preferably 8 to 2,000 nm. In this specification, the average particle size is the value of the cumulative 50% particle size (median diameter; D50) in the volume-based particle size distribution measured by dynamic light scattering.

[0040] The amount of carboxyl groups in the polyhydroxyurethane resin is preferably such that the acid value of the polyhydroxyurethane resin is 15 to 60 mgKOH / g, and more preferably such that it is 25 to 58 mgKOH / g. When the acid value of the polyhydroxyurethane resin is 15 mgKOH / g or higher, the polyhydroxyurethane resin is easily emulsified in water. On the other hand, when the acid value of the polyhydroxyurethane resin is 60 mgKOH / g or lower, the water resistance of the film obtained from the aqueous dispersion of the polyhydroxyurethane resin is easily improved, and the addition of film-forming aids, etc., can be easily omitted during film formation under high-speed coating and drying conditions in actual machines (mass production machines).

[0041] The dispersion (emulsification) stability of polyhydroxyurethane resin is also affected by the molecular weight of the resin. For this reason, the weight-average molecular weight of the polyhydroxyurethane resin is preferably 10,000 to 150,000, more preferably 30,000 to 130,000, and particularly preferably 50,000 to 120,000. The weight-average molecular weight used herein is the polystyrene equivalent value measured by gel permeation chromatography (GPC).

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

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

[0044] The aqueous dispersion may be used with various additives added to suit the required properties during processing (use), or it may contain various additives. Examples of additives include rheological modifiers. Examples of rheological modifiers include starch-based thickeners, inorganic fillers (mica, clay, silica, etc.), and cellulose nanofibers. In particular, by including rheological modifiers containing minerals such as clay and mica in the aqueous dispersion, the gas barrier properties of the resulting film can be further improved. Note that "minerals" include artificial minerals such as synthetic mica. Examples of additives other than rheological 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. Preferred curing agents are those that can crosslink with the hydroxyl groups and carboxylic acid groups of the polyhydroxyurethane resin in the aqueous dispersion to form a crosslinked film. Examples of such curing agents include polyisocyanates, blocked isocyanates, epoxy compounds, metal chelate compounds such as aluminum and titanium, melamine resins, aldehyde compounds, and carbodiimide compounds.

[0046] Polyhydroxyurethane resin has hydroxyl groups in its basic structural repeating unit (i). Therefore, by using an aqueous dispersion of polyhydroxyurethane resin, a coating layer with excellent gas barrier properties can be formed. Furthermore, as described above, the aqueous dispersion of this embodiment contains a polyhydroxyurethane resin manufactured using compound (A)(DCM) represented by general formula (1), so a coating layer with superior adhesion to metals such as metal vapor deposition layers can be formed.

[0047] The gas barrier properties of the coating (coating layer) are exhibited by the presence of hydroxyl groups in the structure of the polyhydroxyurethane resin. The degree of gas barrier properties of the coating depends on the amount of hydroxyl groups in the structure of the polyhydroxyurethane resin. On the other hand, the amount of hydroxyl groups in the structure of the polyhydroxyurethane resin also affects the hardness and adhesion of the coating. From these viewpoints, the hydroxyl value of the polyhydroxyurethane resin is preferably 150 to 250 mgKOH / g. From the viewpoint of obtaining a coating with better gas barrier properties, the above hydroxyl value is more preferably 165 mgKOH / g or more, and particularly preferably 170 mgKOH / g or more. On the other hand, from the viewpoint of obtaining a coating with appropriate hardness and good adhesion even in the case of drying in actual equipment (when it is difficult to dry at a sufficiently high temperature), the above hydroxyl value is more preferably 230 mgKOH / g or less, and particularly preferably 215 mgKOH / g or less.

[0048] The aqueous dispersion of this embodiment contains a polyhydroxyurethane resin having a carboxyl group at a specific location in its molecular structure, and therefore exhibits excellent dispersion stability, allowing for long-term storage. Furthermore, the aqueous dispersion of this embodiment exhibits excellent film-forming properties, enabling the formation of a film even under low-temperature drying conditions, such as around 40°C. Due to these excellent film-forming properties, the polyhydroxyurethane resin in the aqueous dispersion can be suitably used as a film-forming resin in water-based paints or as a binder resin in coating agents.

[0049] Furthermore, since the aqueous dispersion of this embodiment contains a polyhydroxyurethane resin having hydroxyl groups at specific locations in its molecular structure, it is possible to form a coating that exhibits good gas barrier properties. Moreover, since it is possible to control the amount of hydroxyl groups in the polyhydroxyurethane resin, the performance of the coating formed using this aqueous dispersion can be made equivalent to that of a coating formed using a conventional solvent-based polyhydroxyurethane solution.

[0050] <Method for producing an aqueous dispersion of polyhydroxyurethane resin> The above-mentioned aqueous dispersion can be manufactured by the manufacturing method described below. That is, one embodiment of the method for manufacturing the aqueous dispersion of polyhydroxyurethane resin of the present invention (hereinafter also simply referred to as "method for manufacturing aqueous dispersion") is a method for manufacturing the above-mentioned aqueous dispersion, and comprises the following steps. The details of the method for manufacturing the aqueous dispersion of the present invention will be described below. [1] A step (step [1]) in which a diisocyanate compound represented by the following general formula (4) is reacted with a compound represented by the following formula (5) to obtain compound (A). [2] A step (step [2]) in which a diamine compound represented by the following general formula (6) is reacted with a diglycidyl compound represented by the following general formula (7) to obtain a reactant containing compound (B). [3] A step in which the obtained compound (A) and the reactant are subjected to a polyaddition reaction to obtain a polymer (step [3]). [4] The polymer obtained Cyclic acid anhydride structure Step [4] involves reacting an acid anhydride having a carboxyl group to obtain a polyhydroxyurethane resin.

[0051] TIFF0007863649000012.tif51170 (In general formula (4), R1 represents a hydrocarbon group having 6 to 16 carbon atoms including a ring structure; in general formula (6), R3 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms; in general formula (7), R2 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms)

[0052] In step [1], a diisocyanate compound represented by general formula (4) is reacted with compound (GC) represented by formula (5). This yields compound (A). As the diisocyanate compound, a compound having a hydrocarbon group with 6 to 16 carbon atoms that includes a ring structure is used. If a diisocyanate compound having a hydrocarbon group that does not include a ring structure is used, it becomes difficult to form the desired polyhydroxyurethane resin or to obtain an aqueous dispersion.

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

[0054] The amount of glycerin carbonate (GC) to be reacted is preferably 1.5 moles or more, more preferably 1.8 moles or more, and particularly preferably 2.0 moles or more, per mole of diisocyanate compound. The diisocyanate compound and GC can be reacted, for example, by mixing the diisocyanate compound and GC and reacting them at a temperature of 60 to 120°C for 4 to 10 hours. A catalyst commonly used in urethane synthesis may be used during the reaction. The diisocyanate compound and GC may be reacted without a solvent, or in the presence of an organic solvent. Suitable organic solvents include tetrahydrofuran, dioxane, 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], a diamine compound represented by general formula (6) is reacted with a diglycidyl compound represented by general formula (7). This forms compound (B), and a reaction product containing compound (B) can be obtained. Any compound having at least two amino groups in one molecule can be used as the diamine compound. 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 isophoronediamine, norbornanediamine, 1,6-cyclohexanediamine, and piperazine; aromatic polyamines such as o-,m-, or p-phenylenediamine, o-,m-, or p-xylylenediamine, diaminodiphenylmethane, and 2,5-diaminopyridine; and the like.

[0056] Any compound having at least two glycidyl groups in one molecule can be used as the diglycidyl compound. Specific examples of diglycidyl compounds include aromatic diglycidyl ethers such as resorcinol diglycidyl ether, bisphenol A diglycidyl ether, phthalate 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-butanediol diglycidyl ether; and alicyclic diglycidyl ethers such as hydrogenated bisphenol A diglycidyl ether and 1,4-cyclohexanedimethanol diglycidyl ether.

[0057] It is preferable to react a diamine compound and a diglycidyl compound under conditions where the amino group / glycidyl group ratio is 4 / 1 or higher to obtain the reactant, and it is even more preferable to react them under conditions where the amino group / glycidyl group ratio is 5 / 1 or higher. By reacting a diamine compound and a diglycidyl compound in the above ratio, a compound (B) having amino groups at both ends is formed, and a reactant containing excess diamine compound that did not react 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 them at a temperature of 30-60°C for 5-20 hours. Alternatively, the reaction may be carried out without a solvent or in the presence of an organic solvent. Examples of organic solvents include those similar to those used in step [1].

[0059] Step [3] is a step in which compound (A) obtained in step [1] and a reactant containing compound (B) obtained in step [2] are subjected to a polyaddition reaction to obtain a polymer. It is preferable to perform the polyaddition reaction of compound (A) and the reactant such that the equivalent ratio of amino groups in compound (B) to the five-membered ring cyclic carbonate structure in compound (A) (amino groups / five-membered ring cyclic carbonate structure) is in the range of 1.1 to 1.3. The reactant containing compound (A) and compound (B) can be obtained, for example, by mixing compound (A) and the reactant and reacting them at a temperature of 40 to 200°C for 4 to 24 hours. Compound (A) and the reactant may be reacted without a solvent or in the presence of an organic solvent. Examples of organic solvents include those similar to the organic solvents that can be used in step [1].

[0060] In step [4], the polymer obtained in step [3] is used Cyclic acid anhydride structureAn acid anhydride having a carboxyl group is reacted with the polymer. This causes the amino groups in the polymer to react with the acid anhydride, yielding a polyhydroxyurethane resin having a carboxyl group. Since the reaction between the amino groups and the acid anhydride is very fast, it is preferable to react the polymer and the acid anhydride at a temperature of -10 to 40°C. From the viewpoint of suppressing viscosity increase and making it easy to stir, the above temperature is preferably 5°C or higher, more preferably 10°C or higher, and particularly preferably 15°C or higher. On the other hand, from the viewpoint of suppressing gelation due to three-dimensionalization caused by side reactions, the above temperature is more preferably 35°C or lower, and particularly preferably 30°C or lower. The amount of acid anhydride used is preferably such that the equivalent ratio of acid anhydride groups (acid anhydride groups / amino groups) to amino groups in the polymer is 0.8 to 1.0.

[0061] The acid value of the resulting polyhydroxyurethane resin can be controlled by adjusting the types of compound (A), compound (B), and acid anhydride, as well as the usage ratio of compound (A) and compound (B) (equivalent ratio of amino group / five-membered ring cyclic carbonate structure).

[0062] The carboxyl groups introduced using acid anhydrides may remain in their original state. In this case, a polyhydroxyurethane resin can be obtained whose basic structure is a repeating unit (i) containing a structural part represented by general formula (4), in which M in the aforementioned general formula (3) is a hydrogen atom. In the case of a polyhydroxyurethane resin that retains the carboxyl groups (COOH) in this state, these carboxyl groups can also be used in crosslinking and modification reactions.

[0063] When obtaining an aqueous dispersion of polyhydroxyurethane resin, it is preferable to neutralize the carboxyl groups of the polyhydroxyurethane resin in order to promote ionization in water. That is, the method for producing the aqueous dispersion of this embodiment preferably further includes a step (step [5]) in which the carboxyl groups of the polyhydroxyurethane resin obtained in step [4] above are neutralized with alkali, and then mixed with water to perform phase inversion emulsification. At this time, some of the carboxyl groups may be neutralized, but it is more preferable to neutralize all of the carboxyl groups to make the polyhydroxyurethane resin into a neutralized salt. It is preferable to neutralize all of the carboxyl groups into a neutralized salt by using an equivalent molar amount of alkali or an excess amount of about 1 to 10% of the carboxyl groups.

[0064] Examples of alkalis include organic amines such as ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyldiethanolamine, monoethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, N-methylmorpholine, 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 polyhydroxyurethane resin are neutralized with an alkali, and then mixed with water to perform phase inversion emulsification. More specifically, phase inversion is performed by gradually adding water to the solution after alkali neutralization to obtain an O / W type emulsion. The amount of water is preferably adjusted according to the chemical structure of the polyhydroxyurethane resin, the type of organic solvent, the resin concentration in the solution, and the viscosity of the solution. Specifically, it is preferable to add approximately 50 to 200 parts by mass of water per 100 parts by mass of the solution. Heating is not particularly necessary during phase inversion, and it is efficient and preferable to perform the process at a temperature of about 10 to 30°C in order to reduce the solubility of water in the resin solution before phase inversion.

[0066] Furthermore, it is preferable to heat the O / W type emulsion obtained by phase inversion emulsification under reduced pressure. This volatilizes the organic solvent used in the production of the polyhydroxyurethane resin, and an aqueous dispersion in which only the resin component is dispersed in water can be obtained. The heating and reduced pressure conditions vary depending on the boiling point of the organic solvent to be volatilized, but it is preferable to have conditions in which the water does not evaporate first, and it is generally preferable to adjust them in the range of 50 to 300 Torr and 20 to 70°C.

[0067] <Gas barrier film> Since the coating formed using the above-described aqueous dispersion exhibits good gas barrier properties, the coating can be used in a gas barrier film. That is, one embodiment of the gas barrier film of the present invention comprises a base film and a coating layer provided on at least one surface of the base film. This coating layer contains the polyhydroxyurethane resin that constitutes the aforementioned aqueous dispersion. The coating layer constituting this gas barrier film can be formed using the above-described aqueous dispersion of polyhydroxyurethane resin.

[0068] Suitable applications for gas barrier films include packaging materials. For more suitable use as packaging materials, the oxygen permeability of the gas barrier film should be 50 mL / m² at a temperature of 23°C and a relative humidity of 90%. 2 It is preferable that the oxygen permeability is less than or equal to day·atm. Furthermore, it is preferable that the coating layer achieves the above oxygen permeability range with a thickness in the range of 0.1 to 20 μm. It is even more preferable that the thickness of the coating layer be 0.1 to 15 μm, and particularly preferable that be 0.1 to 10 μm.

[0069] As the base film, for example, plastic films conventionally used in the field of packaging materials suitable for gas barrier film applications can be used. Examples of base film materials include 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 copolymer resins such as ethylene-vinyl acetate copolymer; ethylene-vinyl alcohol copolymer resins; polyamide resins such as nylon 6 and nylon 66; polycarbonate resins; acrylic resins; polyimide; polyvinyl chloride resins; and other copolymer resins. Furthermore, these resin materials may contain various additives as needed, such as antistatic agents, ultraviolet absorbers, plasticizers, lubricants, and colorants.

[0070] Furthermore, the coating layer formed using the aforementioned aqueous dispersion exhibits excellent adhesion to metals and metal oxides, such as metal vapor-deposited layers. For this reason, it is preferable to use a laminated film as the base film, in which a metal layer, such as a metal vapor-deposited layer, is provided on at least one surface of a film formed from the various resin materials described above. This makes it possible to create a gas barrier film that has excellent adhesion to the metal layer, even while having a metal layer such as a metal vapor-deposited layer. Examples of metals that constitute the metal layer include aluminum, titanium, copper, silver, and nickel. Examples of metal oxides include metalloid oxides such as silicon, as well as aluminum oxide, silicon dioxide, titanium oxide, and zinc peroxide.

[0071] A coating layer can be formed on at least one surface of a base film by applying the aforementioned aqueous dispersion, or a coating agent (paint, etc.) containing the aqueous dispersion. A coating machine can be used for this coating. Examples of coating machines include gravure coaters, knife coaters, reverse coaters, bar coaters, spray coaters, and slit coaters.

[0072] After coating a substrate film with an aqueous dispersion or coating agent, drying allows water and other substances to evaporate, forming a protective film layer. The aqueous dispersion used to form the protective film layer has excellent film-forming properties, allowing it to form a protective film layer even under low-temperature drying conditions, for example, 60°C or lower, more preferably 50°C or lower, and particularly preferably 40°C or lower. The drying temperature for forming the protective film layer is preferably 25 to 95°C, more preferably 30 to 90°C, and particularly preferably 40 to 80°C. [Examples]

[0073] The present invention will be described in detail below based on examples, but the present invention is not limited to these examples. In the examples and comparative examples, "parts" and "%" are based on mass unless otherwise specified.

[0074] <Synthesis of dicyclocarbonates> (Synthesis Example 1) In a reaction vessel equipped with a stirrer, thermometer, reflux condenser, and vacuum device, 37.86 parts (0.32 mol) of glycerin carbonate (GC) and 76.0 parts of tetrahydrofuran (THF) were added. After raising the temperature to 50°C, 31.13 parts (0.16 mol) of bis(isocyanatomethyl)cyclohexane (HXDI) were added while stirring, taking care to avoid exothermic reaction. 0.002 parts of bismuth 2-ethylhexanoate (2EHBi) were further added and the reaction was allowed to proceed for 1 hour. Analysis by FT-IR (trade name "FT-720", Horiba, Ltd.) was performed, and the reaction was terminated upon confirmation of the disappearance of the absorption peak of the isocyanate group (NCO). The THF was removed by distillation under reduced pressure, and the temperature was raised to 100°C, then held at 15 mmHg for 15 minutes. This yielded dicyclocarbonate (DCM-1), represented by the following formula (1-1), which is a colorless, transparent, viscous liquid.

[0075] TIFF0007863649000013.tif27170

[0076] (Examples 2-6 of the synthesis) Dicyclocarbonates (DCM-2 to DCM-6) were obtained in the same manner as in Synthesis Example 1 described above, except that the types and amounts (moles) of each component shown in Table 1 were used. The meaning of the abbreviations in Table 1 is shown below. HXDI: Bis(isocyanatomethyl)cyclohexane ·XDI: m-Xylylene diisocyanate • TDI: Trilene-2,4-diisocyanate IPDI: Isophorone diisocyanate HMDI: 4,4'-methylene-bis(cyclohexyl isocyanate) • HDI: Hexamethylene diisocyanate GC: Glycerin carbonate

[0077] TIFF0007863649000014.tif74170

[0078] (Synthesis Example 7) A reaction vessel equipped with a stirrer, thermometer, gas inlet tube, and reflux condenser contains epoxy Current 11.32 parts of bisphenol A diglycidyl ether (BGE) (product name "Epotote YD-128", manufactured by Nippon Steel Chemical & Material Co., Ltd.) at a volume of 187 g / eq and 8.69 parts of N,N-dimethylformamide (DMF) were added. After raising the temperature to 60°C, 2.76 parts of 5% LiBr were added. After raising the temperature to 100°C, CO2 (0.1 L / min) was bubbled in and the mixture was reacted for 10 hours. 45.28 parts of isopropanol (IPA) were added at 70°C, and the precipitated white precipitate was filtered and dried in a dryer at 100°C for 1 hour. This yielded a white powder, dicyclocarbonate (DCM-7), represented by the following formula (Y).

[0079] TIFF0007863649000015.tif30170

[0080] (Synthesis Example 8) A reaction vessel equipped with a stirrer, thermometer, gas inlet tube, and reflux condenser contains epoxy Current54.68 parts of resorcinol diglycidyl ether (RGE) at a volume of 117 g / eq and 17.52 parts of DMF were added. After raising the temperature to 60°C, 20.65 parts of 5% LiBr were added. After raising the temperature to 100°C, CO2 (0.1 L / min) was bubbled in and the reaction was allowed to proceed for 10 hours. DMF was removed using an evaporator to obtain dicyclocarbonate (DCM-8), represented by the following formula (Z), which is a yellow, viscous liquid.

[0081] TIFF0007863649000016.tif28170

[0082] <Manufacturing of resin solutions> (Manufacturing Example 1) 27.24 parts (0.20 mol) of m-xylylenediamine (MXDA) and 15.30 parts of THF were placed in a separable flask. Under stirring, 8.46 parts (0.036 mol) of resorcinol diglycidyl ether (RGE) were added, and the mixture was reacted at 40°C for approximately 6 hours to obtain the reaction product. To 51.0 parts (70% solids) of the resulting reaction product, 68.99 parts (0.16 mol) of DCM-1 obtained in Synthesis Example 1 and 32.98 parts of THF were added. The mixture was stirred at 130 rpm and heated to 65°C for 10 hours. Analysis by FT-IR revealed an absorption peak (1,800 cm²) originating from the carbonyl group of the cyclic carbonate. -1 After confirming that the ) had disappeared, the solution was diluted by adding 64.37 parts of THF and 22.53 parts of water. Under stirring, 7.07 parts of maleic anhydride (MAA) were added at 30°C or below. Analysis by FT-IR revealed the absorption peak of the acid anhydride (1,760 cm⁻¹). -1 After confirming the disappearance of ), 0.87 parts of pyromellitic dianhydride (PMDA) were added. Analysis by FT-IR revealed the absorption peak of the acid anhydride (1,760 cm⁻¹). -1 The reaction was terminated after confirming the disappearance of ). In this way, a solution of polyhydroxyurethane resin (RS-1), which is the resin solution before phase inversion emulsification, was obtained.

[0083] (Manufacturing examples 2-8, comparative manufacturing examples 1-3) Polyhydroxyurethane resin solutions (RS-2 to RS-10) were obtained in the same manner as in Production Example 1 described above, except that the types and amounts (parts) of each component shown in Table 2 were used. In Comparative Production Example 3, gelation occurred and precipitated during the reaction between DCM and the diamine compound, making it impossible to produce the resin (resin solution RS-11). The meaning of the abbreviations in Table 2 is shown below. • RGE: Resorcinol diglycidyl ether • BGE: Bisphenol A diglycidyl ether • MXDA: m-xylylenediamine HMD: Hexamethylenediamine • MAA: Maleic anhydride SA: Succinic anhydride • PMDA: Pyromellitic dianhydride

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

[0085] (Weight average molecular weight) The weight-average molecular weight of polyhydroxyurethane resin, in terms of polystyrene equivalent, was measured by gel permeation chromatography (GPC) using dimethylformamide (DMF) as the mobile phase. A GPC instrument (product name "GPC-8220") and columns (product name "Super AW2500+AW3000+AW4000+AW5000") manufactured by Tosoh Corporation were used for the measurements. The measurement results are shown in Table 2.

[0086] TIFF0007863649000017.tif122170

[0087] <Manufacturing of aqueous dispersions> (Example 1) To 100 parts of the resin solution RS-1 obtained in Production Example 1 (containing 45.46% NV and 9.09 parts water), 2.43 parts of 25% aqueous ammonia were added dropwise. After further addition of water dropwise until the resin solid content after THF removal was 30%, the mixture was degassed until the THF odor disappeared to obtain an aqueous dispersion of polyhydroxyurethane resin (WD-1).

[0088] (Examples 2-8, Comparative Examples 1 and 2) Aqueous dispersions of polyhydroxyurethane resin (WD-2 to WD-10) were obtained in the same manner as in Example 1 described above, except that the types of components shown in Table 3 were used.

[0089] <Analysis of aqueous dispersions> (Average particle size) A dynamic light scattering particle size distribution analyzer (product name "NanoTrack UPA-EX150," manufactured by Nikkiso Co., Ltd.) was used to measure the cumulative 50% particle size (median diameter; D50) in the volume-based particle size distribution of resin particles in an aqueous dispersion, and this was used as the average particle size. The results are shown in Table 3.

[0090] (viscosity) The viscosity of the aqueous dispersion was measured using a BM-type viscometer (Tokyo Keiki Seisakusho) under the conditions of rotor No. 2 / 60 rpm / 25°C.

[0091] TIFF0007863649000018.tif56170

[0092] <Manufacturing of laminated films (1)> (Examples 9-16, Comparative Examples 3 and 4) The manufactured aqueous dispersions (WD-1 to WD-10) were coated onto a base 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 resulted in the creation of a laminated film (gas barrier film) consisting of a base film and a coating layer formed on one surface of the base film. The base film used was a 25 μm thick biaxially oriented polyester (PET) film (product name "Lumirror #25-T60," manufactured by Toray Industries; measured oxygen permeability: 51.77 mL / m²). 2(using ·day·atm)

[0093] <Rating> (Gas barrier properties (oxygen permeability)) For the laminated films, the oxygen permeability was measured under constant temperature and humidity conditions of 23°C and 65% relative humidity, in accordance with the provisions of JIS K7126:2006. The results are shown in Table 4. An oxygen permeability measuring device (product name "OX-TRAN 2 / 21ML", manufactured by MOCON Corporation) was used for the measurement. Since a lower oxygen permeability indicates superior gas barrier properties, oxygen permeability was used as an evaluation index for gas barrier properties. In addition, the thickness of the coating layer of the laminated films prepared in each example was measured using a precision thickness measuring instrument (manufactured by Ozaki Seisakusho Co., Ltd.), and it was confirmed that all were 10 μm.

[0094] (Adhesion (adhesive strength)) <Preparation of test specimens> The manufactured aqueous dispersions (WD-1 to WD-10) were coated onto a base film using a bar coater to achieve a dry film thickness of 2 μm. A coating layer was formed by drying in an oven at 80°C for 2 minutes. An adhesive prepared by mixing 9 parts of "Seikabond A601" (manufactured by Dainichi Seika Kogyo Co., Ltd.), 1 part of "Seikabond C-76" (manufactured by Dainichi Seika Kogyo Co., Ltd.), and 10 parts of ethyl acetate was applied to the formed coating layer to a thickness of 4 μm, and then dried in a hot air dryer for 90 seconds to form an adhesive layer. A 60 μm thick CPP film (product name "Pyrene Film-CT P1146", manufactured by Toyobo Co., Ltd.) was overlaid on the formed adhesive layer, and the film was dried at 40°C and 3 kgf / cm². 2 After lamination under these conditions, the film was aged at 40°C for at least 3 days. This resulted in a laminated film in which the base film, coating layer, adhesive layer, and CPP film were laminated in that order. Three types of base films were used, as shown below. • Alumina 1011HG: 12μm thick alumina-coated PET film, product name "Barrierox Non-Coated Type 1011HG", manufactured by Toray Film Processing Co., Ltd. • VmPET: 12μm thick aluminum-coated PET film, product name "VM-PET1510", manufactured by Toray Film Processing Co., Ltd. • TechBarrier LQ: 12μm thick silica-deposited PET film, product name "TechBarrier LQ", manufactured by Mitsubishi Chemical Corporation.

[0095] Three 15mm x 200mm test pieces were taken horizontally from the obtained laminated film, and 50mm from the edge of each test piece was peeled off by hand. Using a constant-speed elongation tensile testing machine (product name "Autograph EZ-S-200N" (Shimadzu Corporation)), T-shaped peeling was performed at a tensile speed of 300mm / min, and the adhesive strength was measured with N=3. The measured adhesive strength (average value) is shown in Table 4.

[0096] TIFF0007863649000019.tif75170

[0097] <Manufacturing of laminated films (2)> (Examples 17-19) The aqueous dispersion WD-1 obtained in Example 1 was mixed with synthetic mica (average particle size 6-7 μm) in amounts of 5, 10, and 15 parts per 100 parts of the resin solids in the aqueous dispersion WD-1 as a rheology modifier to obtain mixtures. Laminated films (gas barrier films) consisting of a base film and a coating layer provided on one surface of the base film were prepared in the same manner as in Examples 9-16 and Comparative Examples 3 and 4 described above, except that the obtained mixtures were used. The oxygen permeability of the prepared laminated films was then measured using the same procedure as described above for "gas barrier properties (oxygen permeability)". The results are shown in Table 5.

[0098] TIFF0007863649000020.tif52170 [Industrial applicability]

[0099] The aqueous dispersion of polyhydroxyurethane resin of the present invention is useful as a material for forming a gas barrier coating layer or the like that constitutes a gas barrier film.

Claims

1. It contains water and a polyhydroxyurethane resin dispersed in the water, the average particle size of which is 1 to 10,000 nm. The polyhydroxyurethane resin contains a repeating unit (i) as its basic structure, which is formed by polymerizing a compound (A) represented by the following general formula (1) and a compound (B) represented by the following general formula (2), and further includes a COOM group introduced after polymerization. An aqueous dispersion of polyhydroxyurethane resin, wherein the repeating unit (i) includes a structural portion represented by the following general formula (3). (In the above general formula (1), R １ (This indicates a hydrocarbon group with 6 to 16 carbon atoms that includes a ring structure.) (In the above general formula (2), R ２ R represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. ３ (This indicates an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.) (In the general formula (3), R １ is synonymous with R in the general formula (1), R １ and R ２ and R ３ are respectively synonymous with R ２ and R ３ in the general formula (2), X represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may contain an oxygen atom or a nitrogen atom, and M represents a hydrogen atom or a counter ion for forming a salt structure.)

2. The aqueous dispersion of the polyhydroxyurethane resin according to claim 1, wherein the polyhydroxyurethane resin has a weight-average molecular weight of 10,000 to 150,000, an acid value of 15 to 60 mgKOH / g, and a hydroxyl value of 150 to 250 mgKOH / g.

3. A method for producing an aqueous dispersion of polyhydroxyurethane resin according to claim 1 or 2, A step of reacting a diisocyanate compound represented by the following general formula (4) with a compound represented by the following formula (5) to obtain compound (A), A step of reacting a diamine compound represented by the following general formula (6) with a diglycidyl compound represented by the following general formula (7) to obtain a reaction product containing the compound (B), The process involves a step of obtaining a polymer by polyaddition reaction between the obtained compound (A) and the reactant, A method for producing an aqueous dispersion of polyhydroxyurethane resin, comprising the steps of: reacting the obtained polymer with an acid anhydride having a cyclic acid anhydride structure to obtain a polyhydroxyurethane resin having a carboxyl group. (In the above general formula (4), R １ R represents a hydrocarbon group having 6 to 16 carbon atoms and containing a ring structure, and in the general formula (6), ３ R represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and in the general formula (7) above, R ２ (This indicates an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 16 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.)

4. A method for producing an aqueous dispersion of polyhydroxyurethane resin according to claim 3, further comprising the step of neutralizing the carboxyl groups of the polyhydroxyurethane resin having carboxyl groups with an alkali, and then mixing it with water to perform phase inversion emulsification.

5. A method for producing an aqueous dispersion of polyhydroxyurethane resin according to claim 3, wherein the diamine compound and the diglycidyl compound are reacted under conditions such that the equivalent ratio of amino groups to glycidyl groups is amino groups / glycidyl groups = 4 / 1 or more to obtain the reaction product.

6. The method for producing an aqueous dispersion of polyhydroxyurethane resin according to claim 3, wherein the acid anhydride is at least one selected from the group consisting of maleic anhydride, pyromellitic anhydride, and succinic anhydride.

7. A base film and A gas barrier film comprising a coating layer provided on at least one surface of the base film, which contains a polyhydroxyurethane resin constituting an aqueous dispersion of the polyhydroxyurethane resin according to claim 1 or 2.

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