JP6563242B2 - Water dispersion of polyhydroxyurethane resin, method for producing water dispersion, and gas barrier film using the water dispersion - Google Patents

Description

  The present invention relates to a technique for a novel aqueous dispersion of a polyhydroxyurethane resin that can be used as a binder resin for paints and coating agents. In particular, it can be used as a water-dispersed paint material, and since carbon dioxide can be incorporated into the chemical structure of polyhydroxyurethane resin, it is possible to provide advanced environmentally friendly products, and the functionality of the coating. From this point of view, the present invention relates to a technology capable of providing an aqueous dispersion of a polyhydroxyurethane resin that exhibits performance as a heat-resistant paint and a gas barrier paint that is comparable to conventional solvent-based paints.

  Polyurethane resins are resins having excellent strength, flexibility, wear resistance, and oil resistance, and are widely used as resins for paints and adhesives. In recent years, a hydroxy polyurethane resin having both a urethane bond and a hydroxyl group in its chemical structure has been developed as a novel polyurethane resin, and its industrial application is expected (see Patent Document 1). Whereas existing polyurethane resins are obtained using isocyanate compounds and polyols as raw materials, hydroxypolyurethane resins are produced by using a combination of these raw materials using epoxy compounds, carbon dioxide and amine compounds as raw materials. Since carbon dioxide used as a raw material is incorporated as a —CO—O— bond in the chemical structure of the hydroxy polyurethane resin, it is a resin material that should be noted from the viewpoint of effective use of carbon dioxide, which is a greenhouse gas. is there.

  The hydroxy polyurethane resin can be made a resin having excellent mechanical strength like the existing polyurethane resin, but further, an application utilizing the functionality derived from the hydroxyl group not present in the structure of the existing polyurethane resin is being studied. For example, application as a heat-resistant coating using a hydroxyl group crosslinking reaction (see Patent Document 2) and application to a gas barrier film utilizing hydroxyl-derived gas barrier properties are being studied (see Patent Document 3).

  As in these prior arts, the paint and coating fields are promising as applications of hydroxypolyurethane. However, the hydroxy polyurethane resins that have been developed so far have a chemical structure with hydroxyl groups as well as urethane bonds, so they have low solubility in organic solvents and differ depending on the substrate and processing equipment used in each application. In many cases, it is difficult to cope with various solvent compositions. On the other hand, by using hydroxypolyurethane resin as an aqueous dispersion, this problem has been solved and, at the same time, application as a water-based paint that is being replaced by a solvent-based paint has been studied and proposed. (See Patent Document 4).

  However, according to the study by the present inventors, this technique results from hydrolysis of the half ester portion because the hydroxyl group of hydroxy polyurethane is carboxylated by the half ester method in order to obtain an aqueous dispersion. However, a problem remains in that the storage stability of the aqueous dispersion is poor, and the problem has not been completely solved. Moreover, the point of utilizing and reducing the hydroxyl group of hydroxypolyurethane has the advantage of contributing to the improvement of water resistance, but has a drawback in applications utilizing the functionality of the hydroxyl group. As another technique, a method of using an amine compound containing a carboxylic acid as a raw material to obtain a polyhydroxyurethane having a carboxyl group has been devised (see Patent Document 5). However, according to the study by the present inventors, this method is such that the carboxyl group and the amino group form an ionic bond in the synthesis reaction system so that the reaction with the cyclic carbonate does not proceed easily, and DMF (dimethylformamide) ) And the like in a high boiling point solvent, and it is difficult to increase the molecular weight. Furthermore, the high boiling point solvent used has a problem that it cannot be distilled off under reduced pressure after phase inversion emulsification, and is not a perfect method for producing an aqueous dispersion (emulsion).

US Pat. No. 3,072,613 JP 2011-102005 A JP 2012-172144 A JP 2007-297544 A JP-A-6-25409

  Therefore, the object of the present invention is to be used as a film-forming resin for water-based paints and coating agents, overcoming the problems of the prior art when using a hydroxypolyurethane resin, and having good stability that can be put into practical use. An object is to provide an aqueous dispersion having an excellent gas barrier property using the aqueous dispersion.

［上記一般式（１）中のＸは、ないか、モノマー単位由来の炭化水素又は芳香族炭化水素からなる化学構造を示し、該構造中に、酸素原子、窒素原子、硫黄原子及びエステル結合を含んでいてもよく、エーテル結合を介してＹ₁及び／又はＹ₂と結合する構造であってもよい。−Ｙ₁−は、下記式（２）〜（５）のいずれか１つの化学構造を示し、また、−Ｙ₂−は、下記式（２）、（６）〜（１０）のいずれか１つの化学構造を示し、式（４）、（５）、（７）〜（１０）中のＲは、水素原子かＣＨ₃を示す。−Ｚ−は、下記一般式（１１）で示される、カルボキシル基又はその陰イオン若しくはその塩を含む化学構造を示す。］

［上記一般式（１１）中、Ｒ₃は炭化水素又は芳香族炭化水素であり、該構造中には酸素原子、窒素原子を含んでもよい。Ｒ₄、Ｒ₅、Ｒ₆は、それぞれ独立して、その構造中にエーテル結合を含んでもよい炭素数１〜１０のアルキレン基であり、Ｒ₇は、ないか、水素原子或いは塩構造となるための対イオンのいずれかを示す。］ The above object is achieved by the present invention described below, that is, the present invention is an aqueous dispersion in which a polyhydroxyurethane resin is dispersed in water at a particle diameter of 0.01 μm to 100 μm, Provided is an aqueous dispersion of a polyhydroxyurethane resin, wherein the hydroxyurethane resin has a repeating unit represented by the following general formula (1).

[X in the general formula (1) represents a chemical structure composed of a hydrocarbon derived from a monomer unit or an aromatic hydrocarbon, and an oxygen atom, a nitrogen atom, a sulfur atom, and an ester bond in the structure. The structure which may be included and may couple | bond with Y < ₁ > and / or Y < ₂ > through an ether bond may be sufficient. —Y ₁ — represents a chemical structure of any one of the following formulas (2) to (5), and —Y ₂ — represents any one of the following formulas (2), (6) to (10). one of the shows the chemical structure of formula (4), (5), R in (7) to (10), a hydrogen atom or CH _3. -Z- represents a chemical structure represented by the following general formula (11) including a carboxyl group or an anion thereof or a salt thereof. ]

[In the general formula (11), R ₃ is a hydrocarbon or an aromatic hydrocarbon, and the structure may contain an oxygen atom or a nitrogen atom. R ₄ , R ₅ , and R ₆ are each independently an alkylene group having 1 to 10 carbon atoms that may include an ether bond in the structure, and R ₇ is not present, or is a hydrogen atom or a salt structure. One of the counter ions for is shown. ]

  Preferred embodiments of the aqueous dispersion of the polyhydroxyurethane resin of the present invention described above include those having the following constitutions. The portion of the repeating unit represented by the general formula (1) and -Z- in the general formula (1) are replaced with the structure of the general formula (11), and in the structure, an oxygen atom, nitrogen And a part of the repeating unit represented by the general formula (1) having a chemical structure which is a hydrocarbon having 1 to 100 carbon atoms or an aromatic hydrocarbon having 6 to 100 carbon atoms, which may contain an atom. The dispersed polyhydroxyurethane resin has a weight average molecular weight of 10,000 to 100,000, an acid value of 10 mgKOH / g to 100 mgKOH / g, and a hydroxyl value of the dispersed polyhydroxyurethane resin. Is in the range of 150 mgKOH / g to 300 mgKOH / g; the dispersed polyhydroxyurethane resin is synthesized using carbon dioxide as a raw material at least in part. Obtained by a polyaddition reaction of a compound having at least two five-membered cyclic carbonate structures and a compound having at least two amino groups, having a five-membered cyclic carbonate structure. That is, the carbon dioxide-derived —O—CO— bond occupies 1 to 30% by mass.

［一般式（１２）中のＲ₄、Ｒ₅、Ｒ₆は、それぞれ独立して、その化学構造中にエーテル結合を含んでもよい炭素数１〜１０のアルキレン基である。］ The present invention provides, as another embodiment, a method for producing an aqueous dispersion using a compound having a five-membered cyclic carbonate structure as a raw material as described above, and includes at least two five-membered cyclic rings in a hydrophilic solvent. A compound having a carbonate structure is subjected to a polyaddition reaction between a compound represented by the following general formula (12) and having at least two primary amino groups and at least one secondary amino group in the molecule. A polyhydroxyurethane resin containing a secondary amino group is obtained, and a polyhydroxyurethane resin containing a carboxyl group to be an ionic group is produced by reacting a cyclic acid anhydride, and the carboxyl group in the resulting hydroxypolyurethane resin is produced. A process for producing an aqueous dispersion of a polyhydroxyurethane resin, characterized by having a step of phase inversion emulsification by adding water thereafter Subjected to.

[R ₄ , R ₅ and R _{6 in} General Formula (12) are each independently an alkylene group having 1 to 10 carbon atoms which may include an ether bond in its chemical structure. ]

As another embodiment, the present invention provides a base material, and at least one of the base materials, an aqueous dispersion of any of the above polyhydroxy urethane resins, or a polyhydroxy urethane resin obtained by the above-described production method And a polyhydroxyurethane coating layer formed using any of the water dispersions of the above, the thickness of the coating layer is 0.1 to 100 μm, and the oxygen permeability is 23 ° C. The gas barrier film is characterized by being 50 mL / m ² · day · atm or less under a constant temperature and humidity of 65%.

  ADVANTAGE OF THE INVENTION According to this invention, the water dispersion formed by disperse | distributing a polyhydroxy urethane resin in the water which can be used as resin for film formation of a water-based coating material or a coating agent is provided. The aqueous dispersion of polyhydroxyurethane resin provided by the present invention is superior in stability and can be stored for a long period of time as compared with the aqueous dispersion of resin provided in the prior art. Since the hydroxyl group of the resin can be controlled to a certain amount, the performance of the coating film (coating layer) obtained from the aqueous dispersion of the polyhydroxyurethane resin of the present invention is equivalent to the coating film obtained from the conventional solvent-type polyhydroxyurethane resin. Performance can be obtained. The aqueous dispersion of the polyhydroxyurethane resin provided in the present invention can be used as a resin for forming a film of an aqueous paint, and by using this, an organic at the time of use, which is a problem with a solvent-based paint, is used. Release of the solvent into the environment is eliminated, the performance of the coating film (coating layer) can be satisfied, and a water-based paint or the like with reduced environmental load can be provided. In addition, the polyhydroxyurethane resin that characterizes the present invention is a resin that can be produced using carbon dioxide as a raw material (formation material). It is also useful in this respect because it can contribute to the reduction of environmental load.

3 is a result of particle size distribution measured for the aqueous dispersion of Example 1. FIG.

［上記一般式（１）中のＸは、ないか、モノマー単位由来の炭化水素又は芳香族炭化水素からなる化学構造を示し、該構造中に、酸素原子、窒素原子、硫黄原子及びエステル結合を含んでいてもよく、エーテル結合を介してＹ₁及び／又はＹ₂と結合する構造であってもよい。−Ｙ₁−は、下記式（２）〜（５）のいずれか１つの化学構造を示し、また、−Ｙ₂−は、下記式（２）、（６）〜（１０）のいずれか１つの化学構造を示し、式（４）、（５）、（７）〜（１０）中のＲは、水素原子かＣＨ₃を示す。−Ｚ−は、下記一般式（１１）で示される、カルボキシル基又はその陰イオン若しくはその塩を含む化学構造を示す。］

［上記一般式（１１）中、Ｒ₃は炭化水素又は芳香族炭化水素であり、該構造中には酸素原子、窒素原子を含んでもよい。Ｒ₄、Ｒ₅、Ｒ₆は、それぞれ独立して、その構造中にエーテル結合を含んでもよい炭素数１〜１０のアルキレン基であり、Ｒ₇は、ないか、水素原子或いは対イオンとで形成した塩構造のいずれかを示す。］ Next, the present invention will be described in detail with reference to preferred embodiments for carrying out the invention. The present invention relates to an aqueous dispersion in which a polyhydroxyurethane resin is dispersed in water at a particle size of 0.01 μm to 100 μm. The polyhydroxyurethane resin contains all or all repeating units represented by the following general formula (1). A part of the repeating unit includes at least a “COOR ₇ ” portion for allowing phase inversion emulsification by adding water represented by the general formula (11). As a result, the polyhydroxyurethane resin is stably dispersed in water with the above particle diameter.

[X in the general formula (1) represents a chemical structure composed of a hydrocarbon derived from a monomer unit or an aromatic hydrocarbon, and an oxygen atom, a nitrogen atom, a sulfur atom, and an ester bond in the structure. The structure which may be included and may couple | bond with Y < ₁ > and / or Y < ₂ > through an ether bond may be sufficient. —Y ₁ — represents a chemical structure of any one of the following formulas (2) to (5), and —Y ₂ — represents any one of the following formulas (2), (6) to (10). one of the shows the chemical structure of formula (4), (5), R in (7) to (10), a hydrogen atom or CH _3. -Z- represents a chemical structure represented by the following general formula (11) including a carboxyl group or an anion thereof or a salt thereof. ]

[In the general formula (11), R ₃ is a hydrocarbon or an aromatic hydrocarbon, and the structure may contain an oxygen atom or a nitrogen atom. R ₄ , R ₅ , and R ₆ are each independently an alkylene group having 1 to 10 carbon atoms that may include an ether bond in the structure thereof, and R ₇ is not present, or is a hydrogen atom or a counter ion. One of the salt structures formed is indicated. ]

  The aqueous dispersion of the polyhydroxyurethane resin of the present invention requires that the resin has a repeating unit represented by the general formula (1), and the entire resin may be composed of this repeating unit. Further, the present invention is not limited to this, and a repeating unit having a chemical structure in which the -Z- moiety of the repeating unit represented by the general formula (1) is different from that of the repeating unit represented by the general formula (1) is mixed. You may have as. Specifically, the chemistry in which the -Z- moiety is a hydrocarbon having 1 to 100 carbon atoms or an aromatic hydrocarbon having 6 to 100 carbon atoms, which may contain an oxygen atom or a nitrogen atom in the structure thereof. It is also a preferable form to mix structures.

The structure represented by the general formula (1), which is a repeating unit contained in the structure of the polyhydroxyurethane resin constituting the present invention, may have the same structure for all the repeating units in the resin. A plurality of the structures defined above may be mixed. For example, the repeating unit possessed in the structure of the polyhydroxyurethane resin may be such that both Y ₁ and Y ₂ in the general formula (1) have the chemical structure of the formula (2), for example, The polyhydroxyurethane resin in which Y ₁ in the general formula (1) is the formula (3) and Y ₂ is mixed with the chemical structure of the formula (6) may be used.

  As a general method for producing a polymer emulsion, there are a forced emulsification method using a surfactant as an emulsifier and a self-emulsification method in which a hydrophilic group is introduced into a polymer chain to form emulsion particles in the polymer chain itself. The aqueous dispersion of the present invention belongs to the above self-emulsifying type, and as shown in the structure of the general formula (11), an anion as a hydrophilic group necessary for emulsification is contained in the resin structure. It is characterized in that self-emulsification is made possible by introducing a carboxyl group which is a sex group. For this reason, the degree to which -Z- in the general formula (1) is mixed with a hydrocarbon or aromatic hydrocarbon is such that the acid value is in the range of 10 mgKOH / g to 100 mgKOH / g for the entire resin. It is preferable to be within.

  The polyhydroxyurethane resin having the structure represented by the general formula (1) can be produced by the following steps. It can be obtained by a polyaddition reaction of compound A having at least two 5-membered cyclic carbonates (hereinafter simply referred to as cyclic carbonates) in one molecule and compound B having at least two amino groups in one molecule.

In the reaction between the cyclic carbonate and the amine that form the polymer chain of the polyhydroxyurethane resin, there are two types of cleavage of the cyclic carbonate, and it is known that two types of structures shown by the following model reactions occur. .

The cyclic carbonate used for the production of the polyhydroxyurethane resin characterizing the present invention is preferably obtained by a reaction between an epoxy compound and carbon dioxide. Specifically, for example, an epoxy compound as a raw material is reacted in the presence of a catalyst at a temperature of 0 ° C. to 160 ° C. in a carbon dioxide atmosphere pressurized to about atmospheric pressure to 1 MPa for 4 to 24 hours. Thereby, the cyclic carbonate compound which fix | immobilized the carbon dioxide to the ester site | part can be obtained.

  By using the cyclic carbonate compound synthesized from carbon dioxide as a raw material in the polyaddition reaction as described above, the resulting polyurethane resin has an —O—CO— bond in which carbon dioxide is immobilized in its structure. It will have. The content of carbon dioxide-derived —O—CO— bonds (carbon dioxide immobilization amount) in the polyurethane resin should be as large as possible from the standpoint of effectively using carbon dioxide as a raw material. The polyhydroxyurethane resin obtained by the synthesis method can contain carbon dioxide in the range of 1 to 20% by mass in its structure.

  Examples of the catalyst used in the reaction of the epoxy compound with carbon dioxide include salts such as lithium chloride, lithium bromide, lithium iodide, sodium chloride, sodium bromide, sodium iodide, and quaternary ammonium salts. Is preferable. The usage-amount is 1-50 mass parts per 100 mass parts of epoxy compounds, Preferably it is 1-20 mass parts. Further, triphenylphosphine or the like may be used in combination in order to improve the solubility of the salts serving as the catalyst.

  The reaction between the epoxy compound and carbon dioxide can also be performed in the presence of an organic solvent. Any organic solvent can be used as long as it dissolves the aforementioned catalyst. Specifically, for example, amide solvents such as N, N-dimethylformamide, dimethyl sulfoxide, dimethylacetamide, N-methyl-2-pyrrolidone, alcohol solvents such as methanol, ethanol, propanol, ethylene glycol, propylene glycol, Preferable examples include ether solvents such as ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, propylene glycol methyl ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, and tetrahydrofuran.

The structure of the cyclic carbonate compound that can be used in the production of the polyhydroxyurethane resin characterizing the present invention is not particularly limited, and any structure having two or more cyclic carbonate structures in one molecule can be used. For example, any of those having a benzene skeleton, an aromatic polycyclic skeleton, a condensed polycyclic aromatic skeleton, an aliphatic type, and an alicyclic type can use a cyclic carbonate. The compounds that can be used in the following are exemplified with structural formulas. Note that R in the structural formulas listed below is either a hydrogen atom or CH ₃ .

The following compounds are exemplified as those having a benzene skeleton, an aromatic polycyclic skeleton, or a condensed polycyclic aromatic skeleton.

Examples of the aliphatic or alicyclic cyclic carbonate include the following compounds.

［一般式（１２）中のＲ₄、Ｒ₅、Ｒ₆は、それぞれ独立して、その化学構造中にエーテル結合を含んでもよい炭素数１〜１０のアルキレン基である。］ The polyhydroxyurethane resin characterizing the present invention has at least two five-membered cyclic rings having a five-membered cyclic carbonate structure synthesized by using carbon dioxide as a raw material at least in part as listed above. It is preferable that the compound is produced by a polyaddition reaction between a compound having a carbonate structure and a compound having at least two amino groups. Preferable amino compounds used in this case include compounds having both at least two primary amino groups and at least one secondary amino group in the molecule represented by the following general formula (12). A conventionally known polyfunctional amine can be used in combination with the amino compound represented by the following general formula (12).

[R ₄ , R ₅ and R _{6 in} General Formula (12) are each independently an alkylene group having 1 to 10 carbon atoms which may include an ether bond in its chemical structure. ]

  Examples of the compound represented by the general formula (12) include diethylenetriamine, triethylenetetramine, iminobispropylamine, tetraethylenepentamine, N, N′-bis (3-aminopropyl) -1,3-propylenediamine. N, N′-bis (3-aminopropyl) -1,4-butylenediamine and the like, and one or more of these compounds can be used.

  Any conventionally known polyfunctional amine compound that can be used in combination with the above amine compound can be used. Preferred examples include ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane (also known as hexamethylenediamine), 1,8-diaminooctane, and 1,10-diamino. Cyclic aliphatic polyamines such as decane, 1,12-diaminododecane, cycloaliphatic polyamines such as isophoronediamine, norbornanediamine, 1,6-cyclohexanediamine, piperazine, 2,5-diaminopyridine, and xylylenediamine (also known as: Aliphatic polyamines having an aromatic ring such as metaxylenediamine, and aromatic polyamines such as metaphenylenediamine and diaminodiphenylmethane.

  The secondary amino group in the structure of the amino compound represented by the general formula (12) does not react with a cyclic carbonate, and can synthesize a polyhydroxyurethane containing a secondary amino group in the main chain. Has already been reported in "J. Polym. Sci., Part A: Polym. Chem. 2005, 43, 5899-5905". Also in the present invention, since the reaction form is as described in the above-mentioned document, polyhydroxyurethane containing a secondary amino group is used as an intermediate for the next reaction. Here, the reaction conditions of the cyclic carbonate compound and the amine compound containing the compound represented by the general formula (12) may be, for example, mixing both and reacting at a temperature of 40 to 200 ° C. for 4 to 24 hours. By doing in this way, the polyhydroxy urethane containing a secondary amino group can be obtained.

  The above reaction can be carried out in the absence of a solvent, but in the present invention, it is preferably carried out in a hydrophilic solvent in consideration of the next step reaction and emulsification step. Examples of preferred hydrophilic solvents that can be used in this case include, for example, tetrahydrofuran, dioxane, dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide, methanol, ethanol, propanol, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, Examples include ethylene glycol dimethyl ether, propylene glycol methyl ether, diethylene glycol monomethyl ether, and diethylene glycol dimethyl ether. Among the solvents listed above, a particularly preferable solvent is tetrahydrofuran that has a boiling point that allows easy evaporation and evaporation after phase inversion emulsification.

  As described above, the production of the polyhydroxyurethane resin that characterizes the present invention can be carried out without using any catalyst, but in order to promote the reaction, It is also possible to do this. For example, basic catalysts such as triethylamine, tributylamine, diazabicycloundecene (DBU), triethylenediamine (DABCO), pyridine and hydroxypyridine, and Lewis acid catalysts such as tetrabutyltin and dibutyltin dilaurate can be used. As a preferable usage-amount of these catalysts, it uses within the range of 0.01-10 mass parts with respect to the total amount (100 mass parts) of the carbonate compound and amine compound which are used for reaction.

  Next, the carboxyl group introduction reaction to the hydroxy polyurethane resin will be described. In the present invention, for example, a carboxyl group is introduced into a hydroxypolyurethane resin by a reaction between a secondary amino group of a polyhydroxyurethane containing a secondary amino group in the main chain obtained by the above-described method and a cyclic acid anhydride.

  The cyclic acid anhydride that can be used in the above reaction is not particularly limited, and any cyclic acid anhydride can be used as long as the carboxyl groups of a compound having a plurality of carboxyl groups are dehydrated and condensed in the molecule. Specifically, for example, succinic anhydride, itaconic anhydride, maleic anhydride, caronic anhydride, citraconic anhydride, glutaric anhydride, diglycolic anhydride 1,2,3,4- Aliphatic acid anhydrides such as butanetetracarboxylic dianhydride and its derivatives, aromatic acid anhydrides such as phthalic acid, trimellitic acid anhydride, 1,2-naphthalic acid anhydride, pyromellitic acid anhydride, Fats such as 1,1-cyclohexanediacetic anhydride, 1-cyclohexene-1,2-dicarboxylic anhydride, 1,1-cyclopentanediacetic anhydride, 5-norbornene-2,3-dicarboxylic anhydride Any of cyclic acid anhydrides can be used. Among these, particularly preferred compounds include, for example, succinic anhydride and maleic anhydride since a low molecular weight compound exhibits emulsion stability when used in a small amount.

  According to the study by the present inventors, the amount of carboxyl groups in the resulting polyhydroxyurethane resin is determined depending on the amount of cyclic acid anhydride used in the above reaction, the type of cyclic acid anhydride, and the type of cyclic carbonate. Can be controlled. Further, according to the study by the present inventors, the amount of carboxyl groups and the emulsified particle diameter are substantially proportional, and the larger the amount of carboxyl groups, the smaller the emulsified particle diameter. On the contrary, when the number of carboxyl groups decreases, the emulsified particle diameter increases, and the emulsified state becomes unstable from a certain size. For these reasons, the emulsified particle diameter of the polyhydroxyurethane resin dispersed in water constituting the aqueous dispersion of the present invention is in the range of 0.01 μm to 100 μm. Although it depends on the use, it is more preferable that the thickness is adjusted so as to be within a range of 0.01 μm to 2 μm. Further, if the introduction amount of the carboxyl group is too small, phase inversion emulsification cannot be carried out, and if too large, the water resistance of the coating is adversely affected. Therefore, the mixing ratio is adjusted so that the acid value is 10 mgKOH / g to 100 mgKOH / g. Is preferred. Moreover, since the stability of emulsified particles is also affected by the molecular weight of the resin, the weight average molecular weight is preferably in the range of 10,000 to 100,000.

  By using the aqueous dispersion of the present invention produced as described above, a coating layer or a film can be formed. However, these also have gas barrier properties. One. The gas barrier properties are exhibited by the presence of hydroxyl groups in the resin structure, and the degree of gas barrier properties of the formed film depends on the amount of hydroxyl groups in the structure of the film-forming resin used. According to the study by the present inventors, the gas barrier property is inferior when there are too few hydroxyl groups, and conversely, when it is too much, there is no problem particularly with respect to the barrier property, but the resin becomes harder and the adhesion becomes worse. A preferable range of the amount of hydroxyl groups in the structure of the resin necessary to achieve such an object is a range of hydroxyl groups of 150 mgKOH / g to 300 mgKOH / g.

  In order to promote ionization in water, the carboxyl group present in the structure of the resin constituting the aqueous dispersion of the present invention may be as it is when the aqueous dispersion is used. It is preferable to neutralize a part, preferably all, of the carboxyl groups to obtain neutralized salts. It is possible to leave the carboxyl group unneutralized for use in cross-linking and modification reactions, but when using it only as an ionic group for emulsification, the neutralizing agent should be equimolar to the carboxyl group. By using an excess amount of about 1 to 10%, it is preferable to use all as neutralized salts.

  In the above, examples of the basic compound used for neutralization include ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyldiethanolamine, monoethanolamine, dimethylethanolamine. , Diethylethanolamine, morpholine, N-methylmorpholine, 2-amino-2-ethyl-1-propanol, trimethylamine, triethylamine, tripropylamine, tributylamine, N-methyldiethanolamine, organic amines such as triethanolamine, lithium, Inorganic salts such as alkali metals such as potassium and sodium, sodium hydroxide, potassium hydroxide, calcium hydroxide, potassium hydroxide and ammonia And the like, which can be used in combination. Among these basic compounds, particularly preferable compounds are those that can volatilize during the formation of the coating film, and for example, it is preferable to use triethylamine. When the neutralized salt is formed using triethylamine or the like, the basic compound volatilizes during the formation of the coating film, so that the water resistance of the coating film (coating film) is improved.

  The polyhydroxyurethane resin containing a carboxyl group that becomes an ionic group in water or a salt thereof obtained by the method described above is phase-shifted by gradually adding water to the solvent solution, and O / W A type of emulsion can be obtained. The amount of water used for phase inversion depends on factors such as the chemical structure of the polyhydroxyurethane resin, the type of solvent used in the resin synthesis, the resin concentration, and the viscosity. About 200 parts. The apparatus used for phase inversion may be the same apparatus as that used for the synthesis reaction, but a continuous emulsifier or disperser can also be used. Usually, the phase inversion step is not particularly required to be heated, and it is efficient and preferable to carry out at a temperature of about 10 ° C. to 30 ° C. in order to reduce the solubility of water in the resin solution before phase inversion.

  Furthermore, the O / W emulsion prepared by phase inversion emulsification is heated under reduced pressure conditions to volatilize the solvent used for the production of the polyhydroxyurethane resin, and only the resin content is dispersed in water. An aqueous dispersion can be obtained. The heating conditions and the reduced pressure conditions at this time differ depending on the boiling point of the solvent to be volatilized, but it is preferable that water does not evaporate first, and is generally adjusted in the range of 300 Torr to 50 Torr and 20 ° C to 70 ° C. The aqueous dispersion of the present invention is obtained by dispersing a polyhydroxyurethane resin in water, but the final solvent is not necessarily water alone, and the solvent before phase inversion remains. Can be used and can be adjusted according to the application.

  The aqueous dispersion of the present invention is, for example, an aqueous dispersion obtained by dispersing the polyhydroxyurethane resin having the above-described specific structure in water with a particle diameter of 0.01 μm to 100 μm, obtained as described above. However, the content of the polyhydroxyurethane resin in water varies depending on the use and is not particularly limited. However, the solid content in the aqueous dispersion is preferably, for example, about 10 to 50%.

  The aqueous dispersion of the present invention can be used by adding various rheology modifiers according to the required properties during processing (in use). Moreover, the water dispersion of this invention may add various additives as needed, for example, antioxidant, a light stabilizer, a ultraviolet absorber, etc. can be added.

  Moreover, the water dispersion of this invention can create a crosslinked coating film by mix | blending and using the hardening | curing agent which can be melt | dissolved / dispersed in water. The curing agent that can be used in this case is not particularly limited. For example, water-dispersible components capable of reacting with hydroxyl groups, polyisocyanates, blocked isocyanates, epoxy compounds, metal chelate compounds such as aluminum and titanium, and melamine resins. Aldehyde compounds, and the like. In addition, a crosslinking agent can be used as long as it can react with a carboxyl group, and water dispersible carbodiimide or the like can be used in addition to the above compound.

  As a method for obtaining a coating film (coating film) using the aqueous dispersion of the present invention, for example, a gravure coater, a knife coater, a reverse coater, a bar coater is applied to a film that uses the aqueous dispersion of the present invention as a base material. Application with a spray coater, slit coater, etc., and volatilization of water and remaining solvent. By doing in this way, the film of this invention which has a base material and the polyhydroxy urethane coating layer formed with the aqueous dispersion of this invention in at least one of this base material can be obtained.

  The film material used as a base material in the above is not particularly limited, and any polymer material conventionally used as a packaging material can be used. Examples thereof include polyolefin resins such as polyethylene, polypropylene and polystyrene, polyester resins such as polyethylene terephthalate and polylactic acid, polyamide resins such as nylon 6 and nylon 66, other polyimides, and copolymers of these resins. . In addition, these polymer materials can appropriately contain, for example, known antistatic agents, ultraviolet absorbers, plasticizers, lubricants, colorants and the like as necessary.

  Next, the present invention will be described in more detail with reference to specific production examples, examples, and comparative examples, but the present invention is not limited to these examples. In the following examples, “part” and “%” are based on mass unless otherwise specified.

[Production Example 1: Synthesis of cyclic carbonate-containing compound (IA)]
100 parts of bisphenol A diglycidyl ether (trade name: jER828, manufactured by Japan Epoxy Resins Co., Ltd.) having an epoxy equivalent of 192, 20 parts of sodium iodide (manufactured by Wako Pure Chemical Industries), and 100 parts of N-methyl-2-pyrrolidone Was charged in a reaction vessel equipped with a stirrer and a reflux with an air opening. Subsequently, carbon dioxide was continuously blown in with stirring, and the reaction was performed at 100 ° C. for 10 hours. Then, 1,400 parts of isopropanol was added to the solution after completion of the reaction to precipitate the reaction product as a white precipitate, which was filtered off. The resulting precipitate was recrystallized from toluene to obtain 52 parts of white powder (yield 42%).

When the powder obtained above was analyzed by FT-IR (manufactured by Horiba, Ltd., also measured by the same apparatus in the following FT-720 production example), the absorption derived from the epoxy group of the raw material in the vicinity of 910 cm ⁻¹ was It disappeared, and absorption from the carbonyl of the carbonate group that was not present in the raw material was confirmed near 1800 cm ⁻¹ . In addition, as a result of analysis by HPLC (manufactured by JASCO, LC-2000; column FinepakSIL C18-T5; mobile phase acetonitrile + water), the peak of the raw material disappeared, a new peak appeared on the high polarity side, and its purity was It was 98%. As a result of DSC measurement (differential scanning calorimetry), the melting point was 178 ° C., and the melting point range was ± 5 ° C.

From the above, this powder was confirmed to be a compound having a structure represented by the following formula in which a cyclic carbonate group was introduced by the reaction of an epoxy group and carbon dioxide. This was abbreviated as IA. The proportion of components derived from carbon dioxide in the chemical structure of IA was 20.5% (calculated value).

[Production Example 2: Synthesis of cyclic carbonate-containing compound (IB)]
Except that hydroquinone diglycidyl ether having an epoxy equivalent of 115 (trade name: Denacol EX203, manufactured by Nagase ChemteX Corp.) was used as the epoxy compound, the same formula (IB) ) Was synthesized (55% yield). The obtained IB was white crystals and had a melting point of 141 ° C. As a result of FT-IR analysis, the absorption derived from the epoxy group of the raw material in the vicinity of 910 cm ⁻¹ disappeared as in IA, and the absorption derived from the carbonyl of the carbonate group not present in the raw material in the vicinity of 1800 cm ^−1. confirmed. The purity by HPLC analysis was 97%. The proportion of the component derived from carbon dioxide in the chemical structure of IB was 28.0% (calculated value).

<Production of carboxyl group-containing hydroxypolyurethane resin used in Examples before being dispersed in water>
[Resin Synthesis Example 1 for Examples]
In a reaction vessel equipped with a stirrer and a reflux opening with an atmosphere opening port, 100 parts of Compound IA obtained in Production Example 1, 16.3 parts of hexamethylenediamine (manufactured by Tokyo Chemical Industry), diethylenetriamine (Tokyo Chemical Industry) 9.6 parts (manufactured by Kogyo) and 189 parts of tetrahydrofuran (THF) as a reaction solvent were added, and the reaction was carried out for 24 hours while stirring at a temperature of 60 ° C. When the resin solution after the reaction was analyzed by FT-IR, 1800 cm ^-1 absorption due carbonyl group of cyclic carbonates that have been observed in the vicinity has completely disappeared, the new urethane bonds in the vicinity of 1760 cm ^-1 Absorption derived from a carbonyl group was confirmed. The amine value measured using the obtained resin solution was 42.1 mgKOH / g as a converted value of 100% resin content. A method for measuring the amine value will be described later. Next, 13.8 parts of phthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) was added to this resin solution and reacted at 40 ° C., and the peak at 1800 cm ⁻¹ derived from acid anhydride carbonyl disappeared by FT-IR. After confirming, the reaction was completed, and a carboxyl group-containing hydroxypolyurethane resin having a structure defined in the present invention before phase inversion emulsification by adding water was obtained.

  In order to confirm the physical properties of the obtained resin, the above resin solution was applied to release paper with a bar coater so that the film thickness at the time of drying was 50 μm, and the solvent was dried in an 80 ° C. oven. The release paper was peeled off to obtain a resin resin film obtained in Resin Synthesis Example 1. The appearance, mechanical strength, oxygen permeability (gas barrier property), resin acid value, resin hydroxyl value, and molecular weight (GPC) of this resin film were measured. Each measuring method will be described later. The results are shown in Table 1.

[Resin Synthesis Example 2 for Examples]
In a reaction container similar to that used in Resin Synthesis Example 1, 100 parts of Compound IA obtained in Production Example 1, 24.4 parts of hexamethylenediamine, 2.4 parts of diethylenetriamine, and 194 tetrahydrofuran are used. The reaction was carried out for 24 hours while stirring at a temperature of 60 ° C. The result of the reaction progress confirmation by FT-IR about the resin solution after reaction was the same as that of Resin Synthesis Example 1. The amine value of the obtained resin was 10.5 mgKOH / g as a converted value of 100% resin content. Next, except that 2.3 parts of maleic anhydride was used in place of the phthalic anhydride used in Resin Synthesis Example 1, the reaction was performed in the same manner as in Resin Synthesis Example 1, and water was added before phase inversion emulsification. A resin solution was obtained. Then, in order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, And the molecular weight (GPC) was measured. The results are shown in Table 1.

[Resin Synthesis Example 3 for Examples]
In a reaction container similar to that used in Resin Synthesis Example 1, 100 parts of Compound IA obtained in Production Example 1, 25.4 parts of metaxylenediamine (manufactured by Mitsubishi Gas Chemical), iminobispropylamine ( 6.1 parts of Tokyo Kasei) and 206 parts of tetrahydrofuran were added, and the reaction was carried out for 24 hours while stirring at a temperature of 60 ° C. The result of the reaction progress confirmation by FT-IR about the resin solution after reaction was the same as that of Resin Synthesis Example 1. The amine value of the obtained resin was 25.5 mgKOH / g as a converted value of 100% resin content. Next, except that 4.6 parts of maleic anhydride was used in place of the phthalic anhydride used in Resin Synthesis Example 1, the reaction was conducted in the same manner as in Resin Synthesis Example 1, and water was added before phase inversion emulsification. A resin solution was obtained. Then, in order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, And the molecular weight (GPC) was measured. The results are shown in Table 1.

[Resin Synthesis Example 4 for Examples]
In a reaction container similar to that used in Resin Synthesis Example 1, 100 parts of Compound IB obtained in Production Example 2, 29.9 parts of hexamethylenediamine, and triethylenetetramine (manufactured by Tokyo Chemical Industry Co., Ltd.) 9.4 parts and 236 parts of tetrahydrofuran were added, and the reaction was performed for 24 hours while stirring at a temperature of 60 ° C. The result of the reaction progress confirmation by FT-IR about the resin solution after reaction was the same as that of Resin Synthesis Example 1. The amine value of the obtained resin was 26.2 mgKOH / g as a converted value of 100% resin content. Next, the resin before the phase inversion emulsification by adding water and reacting in the same manner as in the resin synthesis example 1 except that 12.6 parts of maleic anhydride was used instead of the phthalic anhydride used in the resin synthesis example 1. A solution was obtained. Then, in order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, And the molecular weight (GPC) was measured. The results are shown in Table 1.

[Resin Synthesis Example 5 for Examples]
In a reaction vessel similar to that used in Example 1, 100 parts of Compound IA, 24.1 parts of diethylenetriamine and 220 parts of tetrahydrofuran were added, and the reaction was carried out for 24 hours while stirring at a temperature of 60 ° C. went. The result of the reaction progress confirmation by FT-IR about the resin solution after reaction was the same as that of Resin Synthesis Example 1. The amine value of the obtained resin was 107.0 mgKOH / g as a converted value of 100% resin content. Next, except that 22.9 parts of maleic anhydride was used in place of the phthalic anhydride used in Resin Synthesis Example 1, the reaction was performed in the same manner as in Resin Synthesis Example 1, and water was added before phase inversion emulsification. A resin solution was obtained. Then, in order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, And the molecular weight (GPC) was measured. The results are shown in Table 1.

[Resin Synthesis Example a for Comparative Example a]
In a reaction vessel equipped with a stirrer and a reflux opening having an air opening, 100 parts of Compound IA obtained in Production Example 1, 27.1 parts of hexamethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.), and reaction 204 parts of tetrahydrofuran was added as a solvent, and the reaction was performed for 24 hours while stirring at a temperature of 60 ° C. The result of the reaction progress confirmation by FT-IR about the resin solution after reaction was the same as that of Resin Synthesis Example 1. The obtained resin for a comparative example was a polyhydroxyurethane resin containing no secondary amino group. Next, with the reaction solution kept at 60 ° C., 9.2 parts of maleic anhydride and 9.4 parts of triethylamine as an addition reaction catalyst (also a neutralizing agent) were added and reacted at 60 ° C. for 2 hours. Finished the reaction. When the resin solution for the comparative example after the reaction was analyzed by FT-IR, the peak at 1800 cm ⁻¹ derived from the acid anhydride carbonyl had completely disappeared. In order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, and molecular weight were obtained. (GPC) was measured. The results are shown in Table 1.

[Resin Synthesis Example b for Comparative Example]
Resin except that compound IA obtained in Production Example 1 was 100 parts, metaxylenediamine was 31.8 parts, tetrahydrofuran was 225 parts, maleic anhydride was 18.3 parts, and triethylamine was 18.9 parts. Reaction was performed in the same manner as in Synthesis Example a to obtain a resin solution for Comparative Example. In order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, and molecular weight were obtained. (GPC) was measured. The results are shown in Table 1.

[Resin Synthesis Example c for Comparative Example]
In a reaction container similar to that used above, 100 parts of Compound IA obtained in Production Example 1, 27.1 parts of hexamethylenediamine, and 198 parts of tetrahydrofuran were added and stirred at a temperature of 60 ° C., Reaction for 24 hours was performed and the resin solution for a comparative example was obtained. The obtained resin solution is a normal polyhydroxyurethane resin containing no carboxyl group. In order to confirm the physical properties of the obtained resin, a resin film was prepared in the same manner as in Resin Synthesis Example 1, and the film appearance, mechanical strength, oxygen permeability, resin acid value, resin hydroxyl value, and molecular weight were obtained. (GPC) was measured. The results are shown in Table 1.

(Evaluation)
Each resin obtained in Resin Synthesis Examples 1 to 5 for Examples and Resin Synthesis Examples a to c for Comparative Examples, and each film prepared with each resin were evaluated by the following methods and criteria. . The carbon dioxide content for each resin was calculated as follows. The evaluation results are summarized in Table 1.

[CO2 content]
The carbon dioxide content was determined by calculating the mass% of the carbon dioxide-derived segment of the raw material in the chemical structure of the hydroxy polyurethane resin used in each synthesis example. Specifically, it was shown by a calculated value calculated from the theoretical amount of carbon dioxide contained in the monomer used in synthesizing the compounds IA and IB used in the synthesis reaction of the polyurethane resin. For example, in the case of Resin Synthesis Example 1 for Examples, the amount of the component derived from carbon dioxide of the compound IA used is 20.5%, and from this, in the polyurethane of Resin Synthesis Example 1 for Examples The carbon dioxide concentration of (100 parts × 20.5%) / 139.7 total amount = 14.7% by mass.

[Molecular weight]
GPC measurement using DMF as a mobile phase (manufactured by Tosoh Corporation, GPC-8220; column Super AW2500 + AW3000 + AW4000 + AW5000; the following examples are also the same) was used. The weight average molecular weight is expressed as a polystyrene equivalent value.

[Film appearance]
About each produced resin film, the total light transmittance and haze were measured, and the following references | standards evaluated. The total light transmittance and haze were measured with a haze meter (HZ-1 manufactured by Suga Test Instruments Co., Ltd.) in accordance with JIS K-7105. All the light quantities measured with the haze meter are the total light transmittance, and the ratio of the diffuse transmitted light to the total light transmittance is the haze.
<Evaluation criteria>
○: Total light transmittance 90% or more Haze 0.5% or less ×: Not applicable to ○

[Acid value, hydroxyl value]
In each case, each resin was measured by a titration method based on JIS K-1557, and the content of each functional group per 1 g of the resin was expressed in mg equivalents of KOH. The unit is mgKOH / g.

[Mechanical strength]
As the mechanical strength of each of the produced resin films, the strength at break and the elongation at break were measured. The measurement was performed at room temperature (25 ° C.) by a measurement method using an autograph [manufactured by Shimadzu Corporation, AGS-J (trade name)] in accordance with JIS K-6251.

[Gas barrier properties (oxygen permeability)]
About each produced resin film, the transmittance | permeability of oxygen was measured based on JISK-7126, and this was made into the evaluation value of gas barrier property. That is, it can be judged that the lower the value, the better the gas barrier property. Specifically, the oxygen permeability was measured using a oxygen permeability measuring device (OX-TRAN 2 / 21ML manufactured by MOCON) under a constant temperature and humidity condition at a temperature of 23 ° C. and a humidity of 65%. In addition, since the film thickness after drying was 50 micrometers, the value converted into the film thickness of 20 micrometers was described in Table 1.

<Production of water dispersion>
[Example 1]
In a reaction vessel capable of stirring and distillation under reduced pressure, 100 parts of the resin solution (THF solution) obtained in Resin Synthesis Example 1 for Examples and 2.9 parts of triethylamine were charged. Then, 100 parts of ion-exchanged water was gradually added while stirring at room temperature to carry out phase inversion emulsification. Next, the reaction container was heated to 50 ° C. and depressurized, and THF was distilled off to obtain an aqueous dispersion in which polyhydroxyurethane resin was dispersed in water. The obtained aqueous dispersion was prepared so that the solid content was 23%, and was an aqueous dispersion that was uniform in appearance. The particle size distribution of the polymer dispersed particles in the aqueous dispersion (measured with UPA-EX150 manufactured by Nikkiso) was d50 = 0.079 μm. FIG. 1 shows the measured particle size distribution of the aqueous dispersion. Moreover, when the stability of the obtained water dispersion was preserve | saved and evaluated in a 50 degreeC thermostat, favorable stability was shown.

To the aqueous dispersion obtained above, 0.5 part of Primal RM-8W (Rohm & Haas Japan) was added as a rheology modifier to prepare a paint. And using the obtained coating material, it apply | coated to the following base material and produced the gas-barrier film. Specifically, a 40 μm-thick unstretched polypropylene film (CPP film) [Toyobo, Pyrene P1111 (trade name), measured oxygen permeability: 1500 mL 20 μm / m ² · day · atm is used as the substrate, and its corona On the treated surface, it was applied so that the film thickness upon drying was 10 μm, and dried at 100 ° C., thereby forming a coating layer on the substrate to obtain a multilayer film. Using the obtained multilayer film, the coating film appearance, adhesion, water resistance, and gas barrier properties were evaluated. Each measuring method will be described later. The results are shown in Table 2.

[Example 2]
0.7 parts of triethylamine was added to 100 parts of the resin solution obtained in Resin Synthesis Example 2 for the examples described above, and phase inversion emulsification was performed in the same manner as in Example 1 to obtain an aqueous dispersion of this example. Got. The obtained aqueous dispersion was adjusted to have a solid content of 23% by adding water, but it was a uniform aqueous dispersion in appearance. Then, using the obtained aqueous dispersion, a paint was prepared by adding Primal RM-8W as a rheology modifier in the same manner as in Example 1, and the same base as that used in Example 1 was prepared using this paint. A multilayer film was produced using the materials and conditions. The same evaluation as in Example 1 was performed with the aqueous dispersion and film of this example obtained above, and the results are shown in Table 2.

[Example 3]
1.4 parts of triethylamine was added to 100 parts of the resin solution obtained in the resin synthesis example 3 for the example described above, and phase inversion emulsification was performed in the same manner as in Example 1 to obtain an aqueous dispersion of this example. Got. The obtained aqueous dispersion was adjusted to have a solid content of 23% by adding water, but it was a uniform aqueous dispersion in appearance. Then, using the obtained aqueous dispersion, a paint was prepared by adding Primal RM-8W as a rheology modifier in the same manner as in Example 1, and the same base as that used in Example 1 was prepared using this paint. A multilayer film was produced using the materials and conditions. The same evaluation as in Example 1 was performed with the aqueous dispersion and film of this example obtained above, and the results are shown in Table 2.

[Example 4]
4.7 parts of triethylamine was added to 100 parts of the resin solution obtained in the resin synthesis example 4 for the example described above, and phase inversion emulsification was performed in the same manner as in Example 1 to obtain the aqueous dispersion of this example. Got. The obtained aqueous dispersion was adjusted to have a solid content of 23% by adding water, but it was a uniform aqueous dispersion in appearance. Then, using the obtained aqueous dispersion, a paint was prepared by adding Primal RM-8W as a rheology modifier in the same manner as in Example 1, and the same base as that used in Example 1 was prepared using this paint. A multilayer film was produced using the materials and conditions. The same evaluation as in Example 1 was performed with the aqueous dispersion and film of this example obtained above, and the results are shown in Table 2.

[Example 5]
6.4 parts of triethylamine was added to 100 parts of the resin solution obtained in the resin synthesis example 5 for the example described above, and phase inversion emulsification was performed in the same manner as in Example 1 to obtain the aqueous dispersion of this example. Got. The obtained aqueous dispersion was adjusted to have a solid content of 23% by adding water, but it was a uniform aqueous dispersion in appearance. Using the obtained aqueous dispersion, a coating material was prepared by adding Primal RM-8W as a rheology adjusting agent in the same manner as in Example 1, and using this coating material, the same base material and A multilayer film was produced under the conditions. The same evaluation as in Example 1 was performed with the aqueous dispersion and film of this example obtained above, and the results are shown in Table 2.

[Example 6]
Using the resin solution obtained in Resin Synthesis Example 1 for Examples described above, phase inversion emulsification was performed in the same manner as in Example 1 to obtain an aqueous dispersion. In this example, 5 parts of Duranate WB40-100 (manufactured by Asahi Kasei Chemicals Co., Ltd., NCO% = 16.6%) was added as a crosslinking agent to 100 parts of the obtained aqueous dispersion (solid content: 23%), and dispersed with a disper. A paint was made. Using this paint, a multilayer film was produced using the same base material and conditions as those used in Example 1. After the obtained film was aged at 40 ° C. for 2 days, the coating film appearance, adhesion, water resistance, and gas barrier properties of the multilayer film were evaluated in the same manner as in Example 1. The results are shown in Table 3. The results of the multilayer film of Example 1 are also shown in Table 3.

[Example 7]
A coating material was prepared in the same manner as in Example 6 except that the crosslinking agent was changed to 5 parts of Carbodilite V-02 (Nisshinbo Chemical Co., Ltd., NCN equivalent 590). Using this paint, a multilayer film was produced with the same base material and conditions as used in Example 1, and the obtained film was subjected to an aging treatment at 100 ° C. for 10 minutes, and then the same as in Example 1. The coating film appearance, adhesion, water resistance, and gas barrier properties of the multilayer film were evaluated. The results are shown in Table 3.

[Comparative Example 1]
An aqueous dispersion was obtained in the same manner as in Example 1 except that the triethylamine already used in the reaction was not added to the resin solution obtained in Resin Synthesis Example a for Comparative Example. Then, using the obtained aqueous dispersion, Primal RM-8W was added in the same manner as in Example 1 to prepare a coating material. Using this paint, a multilayer film was produced using the same base material and conditions as those used in Example 1. The same evaluation as in Example 1 was performed with the aqueous dispersion and film of this Comparative Example obtained above, and the results are shown in Table 2.

[Comparative Example 2]
An aqueous dispersion was obtained in the same manner as in Example 1 except that the triethylamine already used in the reaction was not added to the resin solution obtained in Resin Synthesis Example b for Comparative Example. Then, using the obtained aqueous dispersion, Primal RM-8W was added in the same manner as in Example 1 to prepare a coating material. Using this paint, a multilayer film was produced using the same base material and conditions as those used in Example 1. The same evaluation as in Example 1 was performed with the aqueous dispersion and film of this Comparative Example obtained above, and the results are shown in Table 2.

[Comparative Example 3]
Phase inversion emulsification was attempted while gradually adding 100 parts of ion-exchanged water to 100 parts of the hydroxy polyurethane resin solution containing no carboxyl group obtained in Resin Synthesis Example c for Comparative Example. However, when 30 parts were added, the resin separated and was stopped.

(Evaluation)
The characteristics of each of the aqueous dispersions of Examples 1 to 7 and Comparative Examples 1 to 3 obtained above, and the evaluation of each film prepared with the paint obtained using each aqueous dispersion are as follows. went. The results are summarized in Tables 2 and 3.
[Particle size]
About each water dispersion of Examples 1-5 and Comparative Examples 1-3, the particle size distribution was measured using Nikkiso dynamic light scattering type nano track particle size analyzer UPA-EX150. The median diameter (= d50 value) obtained by calculation from the measured particle size distribution is shown in Table 2 as the particle diameter.

[Stability]
The aqueous dispersions of Examples 1 to 5 and Comparative Examples 1 to 3 were placed in a sealed plastic container and stored in a thermostatic bath at 50 ° C. And the state after one month, three months, and six months was observed, respectively, and evaluated according to the following criteria, respectively, and the results are shown in Table 2.
<Evaluation criteria>
◯: There is no sedimentation of the particles and no change in appearance is observed. Δ: The particles are sedimented but are easily redispersed by stirring. X: The emulsified particles are broken and the resin content is sedimented. Cannot be redispersed by stirring

[Appearance of coating film]
About each multilayer film produced in Examples 1-7 and Comparative Examples 1-3, the external appearance of the coating surface was observed visually and the following references | standards evaluated. The results are shown in Tables 2 and 3.
<Evaluation criteria>
◯: Transparent, uniform and glossy coating surface △: Coating surface is not glossy and cloudy ×: Concavities and convexities due to collection

[Adhesion]
About each multilayer film produced in Examples 1-7 and Comparative Examples 1-3, a cellophane tape is crimped | bonded to a part of coating-film surface, it peels slowly by hand, the peeling condition of a coating film is observed, and the following Evaluation based on the criteria. The results are shown in Tables 2 and 3.
<Evaluation criteria>
○: No peeling of the coating film △: Part of the coating film is peeled ×: The coating film is completely peeled off

[water resistant]
About each multilayer film produced in Examples 1-7 and Comparative Examples 1-3, the film was immersed in water, the coating-film surface state 24 hours after was observed visually at room temperature, and the following references | standards evaluated. The results are shown in Tables 2 and 3.
<Evaluation criteria>
○: No change is observed Δ: Part of the coating is whitened ×: The coating is swollen

[Solvent resistance]
About each multilayer film produced in Example 1, 6, and 7, tetrahydrofuran was dripped numerically with the dropper on the coating-film surface, and it wiped off with the waste immediately. And the surface state after wiping off was observed visually and evaluated according to the following criteria. The results are shown in Table 3.
<Evaluation criteria>
○: No change is observed △: Wipe marks remain on the coating film ×: Part of the coating film is peeled off

[Gas barrier properties]
About each film produced in Examples 1-7 and Comparative Examples 1-3, the permeability | transmittance of oxygen was measured based on JISK-7126, and this was made into the evaluation value of gas barrier property. That is, it can be judged that the lower the value, the better the gas barrier property. Specifically, oxygen permeability (oxygen) was measured under constant temperature and humidity conditions using an oxygen permeability measuring device (manufactured by MOCON, OX-TRAN 2 / 21ML) at a temperature of 23 ° C. and a humidity of 65%. Transmittance) was measured. The oxygen permeability of the films prepared in the resin synthesis examples 1 to 5 for the examples shown in Table 1 above is a value converted to a film thickness of 20 μm, whereas the examples shown in Tables 2 and 3 are used. The measured values of the gas barrier properties of the films of Examples 1 to 7 and Comparative Examples 1 and 2 are oxygen permeability as a film constituent. The thickness of the coating layer obtained by applying the paints of Examples or Comparative Examples on the film was measured using a precision thickness measuring instrument (manufactured by Ozaki Seisakusho) and confirmed to be 10 μm. The results are shown in Tables 2 and 3.

  As shown in Table 1, the hydroxyurethane resin before phase inversion emulsification by adding water used in the aqueous dispersions of the examples of the present invention is the same as the hydroxyurethane resin for comparative examples obtained by the conventional formulation. In comparison, the carboxyl group was introduced without reducing the amount of hydroxyl groups. As a result, in the resin for the examples of the present invention, the decrease in mechanical strength exhibited by the cohesive force of the hydroxyl group can be reduced, and a polyhydroxyurethane resin having no gas barrier property (resin synthesis example for comparative example) It was confirmed that a, b) and the performance equivalent to the polyhydroxyurethane resin which does not introduce | transduce a carboxyl group (resin synthesis example c for a comparative example) are shown.

  Further, by introducing carboxyl groups into the structure of the hydroxyurethane resin before phase inversion emulsification by adding water, as shown in Table 2, in the examples of the present invention, stable water dispersion with a small particle diameter The body can be made. In particular, in terms of storage stability, it was possible to store for a long period of time as compared with aqueous dispersions (Comparative Examples 1 and 2) prepared by conventional formulations. This is because, in the conventional aqueous dispersion, the carboxyl group modification site is eliminated by hydrolysis because the carboxyl group is introduced by the half ester, whereas the amide bond used in the examples of the present invention is used. This is because the hydroxy polyurethane resin introduced with a carboxyl group is less prone to hydrolysis. Further, as shown in Table 3, the aqueous dispersion of the present invention can obtain a crosslinked coating using various crosslinking agents depending on the resin constituting the solvent, and by using the crosslinking agent, solvent resistance, It was confirmed that the adhesion was improved and the cross-linked film also had a high gas barrier property.

  As described above, according to the present invention, an aqueous dispersion of a polyhydroxyurethane resin that can be stored for a long period of time, which is required industrially, can be provided. In order to obtain a stable aqueous dispersion state, carboxyl groups were introduced into the structure of the hydroxyurethane resin prior to phase inversion emulsification by adding water, but the conventional polyhydroxyurethane resin was also present due to the simultaneous presence of hydroxyl groups. It has the same mechanical strength and gas barrier properties as the film formed by the above method, and can be expected to be applied to conventional assumed applications. Furthermore, since the polyhydroxyurethane resin characterizing the present invention can use carbon dioxide as a raw material, it is a technology expected from the viewpoint of protecting the global environment.

Claims (5)

An aqueous dispersion of a polyhydroxyurethane resin that is used for a binder resin of a paint or a coating agent in which a polyhydroxyurethane resin is dispersed in water at a particle size of 0.01 μm to 100 μm,
The polyhydroxyurethane resin has a repeating unit represented by the following general formula (1), its weight average molecular weight is 10,000 to 100,000, its acid value is 10 mgKOH / g to 100 mgKOH / g, and And having a hydroxyl value of 175 mgKOH / g to 300 mgKOH / g and an oxygen permeability of 23 ° C. and a constant temperature and humidity of 65%, the value converted to a film thickness of 20 μm is 25 mL / m ² · day · atm or less. An aqueous dispersion of a polyhydroxyurethane resin, characterized in that there is.

[X in the general formula (1) represents a chemical structure composed of an aliphatic hydrocarbon, an alicyclic hydrocarbon, or an aromatic hydrocarbon derived from a monomer unit, in which an oxygen atom, nitrogen An atom, a sulfur atom, and an ester bond may be included, and a structure that bonds to Y ₁ and / or Y ₂ via an ether bond may be used. —Y ₁ — represents a chemical structure of any one of the following formulas (2) to (5), and —Y ₂ — represents any one of the following formulas (2), (6) to (10). one of the shows the chemical structure of formula (4), (5), R in (7) to (10), a hydrogen atom or CH _3. -Z- represents a chemical structure represented by the following general formula (11) including a carboxyl group or an anion thereof or a salt thereof. ]

[In the general formula (11), R ₃ represents an aliphatic hydrocarbon, an alicyclic hydrocarbon, or an aromatic hydrocarbon, and the structure may contain an oxygen atom or a nitrogen atom. R ₄ , R ₅ and R ₆ are each independently an alkylene group having 1 to 10 carbon atoms which may contain an ether bond in its structure, and R ₇ is a hydrogen atom or a pair for forming a salt structure. One of the ions is shown. ]   The portion of the repeating unit represented by the general formula (1) and -Z- in the general formula (1) are replaced with the structure of the general formula (11), and in the structure, an oxygen atom, nitrogen The above general formula having a chemical structure which may contain an atom and is an aliphatic hydrocarbon having 1 to 100 carbon atoms, an alicyclic hydrocarbon having 1 to 100 carbon atoms or an aromatic hydrocarbon having 6 to 100 carbon atoms The aqueous dispersion of polyhydroxyurethane resin according to claim 1, wherein the repeating unit portion represented by (1) is mixed.   The dispersed polyhydroxyurethane resin includes at least two compounds having a five-membered cyclic carbonate structure having a five-membered cyclic carbonate structure synthesized using carbon dioxide as a raw material at least in part, and at least two It is obtained by the polyaddition reaction of the compound which has an amino group, 1-30 mass% of the total mass accounts for the said carbon dioxide-derived -O-CO- bond. An aqueous dispersion of polyhydroxyurethane resin. A method for producing an aqueous dispersion of a polyhydroxyurethane resin according to claim 3,
A compound having at least two five-membered cyclic carbonate structures in a hydrophilic solvent, at least two primary amino groups in the molecule represented by the following general formula (12), and at least one secondary amino group: A polyhydroxyurethane resin containing a secondary amino group is obtained by polyaddition reaction with a compound having both, and a polyhydroxyurethane resin containing a carboxyl group that becomes an ionic group by reacting with a cyclic acid anhydride. A process for producing an aqueous dispersion of a polyhydroxyurethane resin, characterized by comprising a step of neutralizing carboxyl groups in the obtained hydroxypolyurethane resin and then adding water to perform phase inversion emulsification.

[R ₄ , R ₅ and R _{6 in} General Formula (12) are each independently an alkylene group having 1 to 10 carbon atoms which may include an ether bond in its chemical structure. ] It has a base material and the polyhydroxy urethane coating layer formed using the aqueous dispersion of the polyhydroxy urethane resin of any one of Claims 1-3 in at least one of this base material. The film layer has a thickness of 0.1 to 100 μm and an oxygen permeability of 50 mL / m ² · day · in terms of a film thickness of 10 μm under a constant temperature and humidity of 23 ° C. and 65%. A gas barrier film characterized by being atm or less.

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