Coating agent, film, and pouch

Abstract

The purpose of the present invention is to provide a coating agent capable of forming a coating film (in other words, a coating layer) which exhibits excellent sliding properties of fluid substances such as curries, sauces, ketchup, mayonnaise and feces, and which minimizes or reduces excessive cracking. Another purpose of the present invention is to provide a film and a pouch which include a coating layer. This coating agent contains: a polymer containing a monomer unit containing a betaine structure; and an ionic liquid. This film includes a substrate film and a coating layer formed from the coating agent on the substrate film. The pouch comprises the film (in other words, a film including the substrate film and the coating layer).

Description

Coatings, Films, and Pouches

[0001] The present invention relates to coatings, films, and pouches.

[0002] A stoma is an artificial opening created in the abdominal wall through surgery or other means. It is an opening created to allow waste to leave the body when, for example, part of the digestive tract (such as the large intestine or rectum) is removed or when part of the urethra is removed.

[0003] The bag that collects waste from the stoma is sometimes called a stoma pouch (hereinafter sometimes referred to as a "stoma appliance pouch"). When a certain amount of waste accumulates in the stoma pouch, the waste is discarded (for example, by flushing it down the toilet), and the stoma pouch can be continued to be used after cleaning as necessary. Because waste, especially feces, is viscous, it takes a fair amount of effort to remove the feces from the stoma pouch.

[0004] In order to facilitate the expulsion of feces from a stoma pouch, it is known to form a functional layer containing functional particles (specifically, hydrophobic particles and / or lipophobic particles) on the inner surface of the stoma pouch (see Patent Document 1).

[0005] Patent No. 6932547 Patent No. 6467226 WO / 2021 / 241295

[0006] However, it may be difficult to manufacture a stoma pouch by heat sealing using the stoma pouch film actually produced in Patent Document 1 (i.e., the stoma pouch film having a polyester film and a functional layer produced in the examples of Patent Document 1). This is because the content of functional particles in the functional layer of the stoma pouch film actually produced in Patent Document 1 is quite high, making it difficult to bond the functional layers together by heat sealing. In other words, it is difficult to bond the functional layers together with strong adhesive strength by heat sealing.

[0007] On the other hand, to facilitate the expulsion of feces from the stoma pouch, it is conceivable to treat the surface of the film with a fluorine compound having a low surface tension. However, it may be difficult to produce a stoma pouch by heat sealing using a film surface-treated with a fluorine compound. This is because it is difficult to bond surfaces that have been surface-treated with a fluorine compound together with a strong adhesive force by heat sealing.

[0008] In light of the above, it is meaningful to propose a new technology that can make it easier to empty stool from a stoma pouch.

[0009] Depending on the application of the pouch, it may be required that viscous fluids such as curry, sauce, ketchup, and mayonnaise (hereinafter referred to as "fluids") be easily dispensed. Thus, depending on the application of the pouch or film, it may be required that the fluids slide off easily, i.e., that they have slip-off properties.

[0010] An object of the present invention is to provide a coating agent capable of forming a coating film (i.e., a coating layer) that exhibits excellent sliding properties for fluids (e.g., curry, sauce, ketchup, mayonnaise, feces, etc.) and that suppresses or reduces the occurrence of excessive cracks. Another object of the present invention is to provide a film or pouch that includes a coating layer that exhibits excellent sliding properties for fluids and that suppresses or reduces the occurrence of excessive cracks.

[0011] In order to solve this problem, the present invention has the following configuration [1]: [1] A coating agent comprising a polymer including a monomer unit having a betaine structure (hereinafter, sometimes referred to as a "betaine polymer") and an ionic liquid.

[0012] According to [1], the coating agent contains a polymer containing a monomer unit having a betaine structure, and therefore can form a coating film, i.e., a coating layer, that has excellent sliding properties for fluids (e.g., curry, sauce, ketchup, mayonnaise, feces, etc.). This will be explained. Since the betaine polymer contains a monomer unit having a betaine structure, it can form a coating film that has excellent hydrophilicity. This coating film can absorb the moisture of the fluid and swell when it comes into contact with the fluid. Therefore, this coating film can form a lubricated surface when it comes into contact with the fluid. Because this surface is lubricated, it has excellent sliding properties for fluids, i.e., excellent sliding properties. Therefore, the coating agent of [1] can form a coating film, i.e., a coating layer, that has excellent sliding properties for fluids.

[0013] Furthermore, since the coating agent contains an ionic liquid, excessive cracking in the coating film can be suppressed or reduced. This will be explained below. Since betaine polymers contain monomer units containing a betaine structure, they tend to have high cohesive strength, and therefore the cohesive strength of the coating film also tends to be high. Therefore, cracks may occur in coating films containing betaine polymers. In contrast, according to [1], the ionic liquid can interact closely with the betaine polymer, thereby reducing the cohesive strength between the betaine polymers. Therefore, the coating agent of [1] can suppress or reduce excessive cracking in the coating film.

[0014] The present invention preferably has the following configurations [2] to

[14] . [2] The polymer is obtained by polymerizing at least a monomer represented by formula I, In the formula I, R １ is a (meth)acryloylaminoalkyl group having an alkyl group with 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms, and R ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms, and R ４is an alkylene group having 1 to 4 carbon atoms or an oxyalkylene group having 1 to 4 carbon atoms. [3] The coating agent according to [1] or [2], wherein the polymer contains at least one of a silanol group and an alkoxysilyl group. [4] The coating agent according to any one of [1] to [3], further containing a silicone-based leveling agent. [5] The coating agent according to [4], wherein the silicone-based leveling agent is polyether-modified silicone oil. [6] The coating agent according to any one of [1] to [5], further containing an alcohol-based solvent. [7] The coating agent according to any one of [1] to [6], further containing water. [8] The coating agent according to any one of [1] to [7], which is used to coat a substrate film. [9] A film comprising a substrate film and a coating layer formed on the substrate film using the coating agent according to any one of [1] to [8].

[10] The film according to [9], wherein the substrate film contains at least one of a polyolefin and a polyester.

[11] The film according to [9] or

[10] , which is used as a packaging film.

[12] The film according to any one of [9] to

[11] , which is used as a pouch film.

[13] A pouch comprising the film according to any one of [9] to

[12] .

[14] The pouch according to

[13] , which is a stoma pouch.

[0015] The present invention also preferably has the following configuration:

[15] The London dispersion term δ of the Hansen solubility parameter (HSP) in the ionic liquid ｄ is 10.0 MPa １／２ Over 18.3 MPa １／２ and the dipole-dipole force term δ ｐ is 10.0 MPa １／２ Over 20.0 MPa １／２ is less than or equal to the hydrogen bond strength term δ ｈ is 14.0 MPa １／２ The coating agent, film, or pouch according to any one of the above configurations, which is as follows:

[16] R １

[17] The coating agent, film, or pouch according to any one of the above configurations, wherein R is a (meth)acryloylaminoalkyl group having 1 to 4 carbon atoms in the alkyl group. １

[18] The coating agent, film, or pouch according to any one of the above configurations, wherein R is a methacryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group. ２ and R ３

[19] The coating agent, film, or pouch according to any one of the above configurations, wherein R is each independently an alkyl group having 1 to 4 carbon atoms. ４is an alkylene group having 1 to 4 carbon atoms.

[20] The coating agent, film, or pouch according to any of the above configurations, wherein the content of the betaine polymer in the coating agent is 30% by mass or more, or 40% by mass or more, when the total content of the betaine polymer and the ionic liquid is taken as 100% by mass.

[21] The coating agent, film, or pouch according to any of the above configurations, wherein the content of the betaine polymer in the coating agent is 30% by mass or more and 90% by mass or less, when the total content of the betaine polymer and the ionic liquid is taken as 100% by mass.

[22] The coating agent, film, or pouch according to any of the above configurations, wherein the content of the betaine polymer in the coating agent is 50% by mass or more, or 60% by mass or more, when the total content of the betaine polymer and the ionic liquid is taken as 100% by mass.

[23] The coating agent, film, or pouch according to any one of the preceding configurations, wherein the ionic liquid contains a bis(fluorosulfonyl)imide anion.

[24] The coating agent, film, or pouch according to any one of the preceding configurations, wherein the ionic liquid contains a 1-ethyl-3-methylimidazolium cation.

[25] The coating agent, film, or pouch according to any one of the preceding configurations, wherein the ionic liquid contains an ammonium cation.

[26] The coating agent, film, or pouch according to any one of the preceding configurations, wherein the ionic liquid contains an N,N-dimethyl-N,N-dihydroxyethylammonium cation.

[27] The coating agent, film, or pouch according to any one of the preceding configurations, wherein the content of the betaine polymer in the coating agent is 93% by mass or less, or 85% by mass or less, when the total content of the betaine polymer and the ionic liquid is 100% by mass.

[28] The film or pouch according to any one of the preceding configurations, wherein the thickness of the coating layer is 0.05 μm or more and 10 μm or less.

[29] R ２ and R ３is an alkyl group having one carbon atom, i.e., a methyl group.

[0016] According to the present invention, it is possible to provide a coating agent capable of forming a coating film (i.e., a coating layer) that has excellent sliding properties for fluids (e.g., curry, sauce, ketchup, mayonnaise, feces, etc.) and in which excessive cracking is suppressed or reduced. According to the present invention, it is also possible to provide a film or a pouch that has excellent sliding properties for fluids and includes a coating layer in which excessive cracking is suppressed or reduced.

[0017] Hereinafter, embodiments of the present invention will be described in detail.

[0018] <1. Coating Agent> <1.1. Betaine Polymer> The coating agent of this embodiment contains a polymer containing a monomer unit having a betaine structure, i.e., a betaine polymer. Because the coating agent of this embodiment contains a betaine polymer, it can form a coating film, i.e., a coating layer, that exhibits excellent sliding properties for fluids (e.g., curry, sauce, ketchup, mayonnaise, feces, etc.). This will be explained below. Because the betaine polymer contains a monomer unit having a betaine structure, it can form a coating film that exhibits excellent hydrophilicity. This coating film can absorb the moisture from the fluid and swell upon contact with the fluid. Therefore, this coating film can form a lubricated surface upon contact with the fluid. Because this surface is lubricated, it exhibits excellent sliding properties for fluids, i.e., excellent sliding properties. Therefore, the coating agent of this embodiment can form a coating film, i.e., a coating layer, that exhibits excellent sliding properties for fluids.

[0019] The betaine polymer may be a polymer in which at least a betaine monomer is polymerized, i.e., the betaine polymer may be a polymer in which a monomer containing a betaine monomer is polymerized.

[0020] Examples of betaine monomers include sulfoxybetaine monomers, carboxybetaine monomers, and phosphorylbetaine monomers. Among these, sulfoxybetaine monomers are preferred. These may be used alone or in combination of two or more.

[0021] Preferably, the betaine monomer contains a (meth)acryloyl group. Here, "(meth)acryloyl" means "acryloyl" or "methacryloyl." When the betaine monomer contains a (meth)acryloyl group, the betaine polymer can be an acrylic polymer.

[0022] As a sulfoxybetaine monomer containing a (meth)acryloyl group, the monomer represented by formula I is preferred because of its ready availability. In Formula I, R １ is a (meth)acryloylaminoalkyl group having an alkyl group with 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms. ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having an alkyl group having 1 to 4 carbon atoms. ４ is an alkylene group having 1 to 4 carbon atoms or an oxyalkylene group having 1 to 4 carbon atoms.

[0023] R １is a (meth)acryloylaminoalkyl group having 1 to 4 carbon atoms in the alkyl group, or a (meth)acryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group. Examples of (meth)acryloylaminoalkyl groups having 1 to 4 carbon atoms include a (meth)acryloylaminomethyl group, a (meth)acryloylaminoethyl group, a (meth)acryloylaminopropyl group, and a (meth)acryloylaminobutyl group. Examples of (meth)acryloyloxyalkyl groups having 1 to 4 carbon atoms in the alkyl group include a (meth)acryloyloxymethyl group, a (meth)acryloyloxyethyl group, a (meth)acryloyloxypropyl group, and a (meth)acryloyloxybutyl group. Of these, a (meth)acryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group is preferred, and a methacryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group is more preferred.

[0024] R ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group. Examples of alkyl groups having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group (e.g., an n-propyl group, an i-propyl group), and a butyl group (e.g., an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, and a cyclobutyl group). Examples of hydroxyalkyl groups having 1 to 4 carbon atoms include a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, and a hydroxybutyl group. Examples of (meth)acryloyloxyalkyl groups having 1 to 4 carbon atoms in the alkyl group include a (meth)acryloylaminomethyl group, a (meth)acryloylaminoethyl group, a (meth)acryloylaminopropyl group, and a (meth)acryloylaminobutyl group. Among these, alkyl groups having 1 to 4 carbon atoms are preferred.

[0025] R ４is an alkylene group having 1 to 4 carbon atoms, or an oxyalkylene group having 1 to 4 carbon atoms. Examples of alkylene groups having 1 to 4 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group. Examples of oxyalkylene groups having 1 to 4 carbon atoms include an oxymethylene group, an oxyethylene group, an oxypropylene group, and an oxybutylene group. Of these, alkylene groups having 1 to 4 carbon atoms are preferred.

[0026] In Formula I, R １ is a (meth)acryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group, and R ２ and R ３ are each independently an alkyl group having 1 to 4 carbon atoms, and R ４ is preferably an alkylene group having 1 to 4 carbon atoms. １ is a methacryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group, and R ２ and R ３ are each independently an alkyl group having 1 to 4 carbon atoms, and R ４ is also preferably an alkylene group having 1 to 4 carbon atoms. Specific examples of the monomer represented by formula I, i.e., the sulfoxybetaine monomer represented by formula I, include the compounds exemplified as sulfoxybetaine monomers in Patent Document 2 (i.e., Japanese Patent No. 6467226).

[0027] An example of a carboxybetaine monomer is the monomer represented by Formula II: In Formula II, R ５ and R ６ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ７ is a (meth)acryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group. ８ is an alkylene group having 1 to 4 carbon atoms.

[0028] R ５ and R ６are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group.

[0029] R ７ is a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms. Examples of the (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms include a (meth)acryloyloxymethyl group, a (meth)acryloyloxyethyl group, a (meth)acryloyloxypropyl group, and a (meth)acryloyloxybutyl group.

[0030] R ８ is an alkylene group having 1 to 4 carbon atoms. Examples of the alkylene group having 1 to 4 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group.

[0031] An example of a phosphoryl betaine monomer is a monomer represented by formula III: In Formula III, R ９ is a (meth)acryloyloxyalkyl group having 1 to 4 carbon atoms in the alkyl group. １０ is an alkylene group having 1 to 4 carbon atoms. １１ , R １２ and R １３ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0032] R ９ is a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms. Examples of the (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms include a (meth)acryloyloxymethyl group, a (meth)acryloyloxyethyl group, a (meth)acryloyloxypropyl group, and a (meth)acryloyloxybutyl group.

[0033] R １０ is an alkylene group having 1 to 4 carbon atoms. Examples of the alkylene group having 1 to 4 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group.

[0034] R １１ , R １２ and R １３ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group.

[0035] The betaine polymer may contain a monomer unit other than the monomer unit containing a betaine structure, i.e., the betaine polymer may be a polymer obtained by polymerizing a monomer other than a betaine monomer.

[0036] Examples of monomers other than betaine monomers include styrene, α-hydroxystyrene, p-hydroxystyrene, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, neopentyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cetyl (meth)acrylate, ethyl carbitol (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and methyl acrylate. Examples of suitable acrylates include methoxyethyl acrylate, methoxybutyl (meth)acrylate, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-propyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, N-tert-butyl(meth)acrylamide, N-octyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, (meth)acryloylmorpholine, diacetone(meth)acrylamide, styrene, methyl itaconate, ethyl itaconate, vinyl acetate, vinyl propionate, N-vinylpyrrolidone, and N-vinylcaprolactam. These may be used alone or in combination of two or more.

[0037] When all the monomer units in the betaine polymer are taken as 100 mol %, the monomer units containing a betaine structure are preferably 80 mol % or more, more preferably 90 mol % or more, and even more preferably 95 mol % or more.

[0038] The betaine polymer preferably contains at least one of a silanol group and an alkoxysilyl group, more preferably a silanol group, which allows crosslinking between betaine polymers and thereby improves the durability of the coating film.

[0039] To obtain a betaine polymer containing at least one of a silanol group and an alkoxysilyl group, for example, monomers containing a betaine monomer may be polymerized in the presence of a chain transfer agent containing a compound containing an alkoxysilyl group.

[0040] An example of a compound containing an alkoxysilyl group is a compound represented by formula IV: In Formula IV, R １４ , R １５ and R １６ are each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and R １４ , R １５ and R １６ At least one of R is an alkoxy group having 1 to 4 carbon atoms. １７ represents an alkylene group having 1 to 12 carbon atoms.

[0041] R １４ , R １５ and R １６ are each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkoxy group having 1 to 4 carbon atoms include a methoxy group, an ethoxy group, a propoxy group (e.g., an n-propoxy group, an i-propoxy group), and a butoxy group (e.g., an n-butoxy group, an i-butoxy group, an s-butoxy group, and a t-butoxy group).

[0042] R １４ , R １５ and R １６ At least one of R is an alkoxy group having 1 to 4 carbon atoms. １４ , R １５ and R １６ Preferably, at least one of the groups is a methoxy group.

[0043] R １４ , R １５ and R １６ It is preferable that at least two of the R groups are alkoxy groups having 1 to 4 carbon atoms. When at least two of the R groups are alkoxy groups having 1 to 4 carbon atoms, it is believed that the durability of the coating film can be further improved. １４ , R １５ and R １６ More preferably, at least two of the groups are methoxy groups.

[0044] R １４ , R １５ and R １６ It is preferable that all of R are alkoxy groups having 1 to 4 carbon atoms. When all of R are alkoxy groups having 1 to 4 carbon atoms, it is believed that the durability of the coating film can be further improved. １４ , R １５ and R １６ More preferably, all of are methoxy groups.

[0045] R １７ represents an alkylene group having 1 to 12 carbon atoms. The number of carbon atoms in the alkylene group is preferably 2 or more, and more preferably 3 or more. The number of carbon atoms in the alkylene group is preferably 6 or less, more preferably 4 or less, and even more preferably 3. Examples of alkylene groups having 1 to 12 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group.

[0046] An example of the compound represented by formula IV is 3-mercaptopropyltrimethoxysilane.

[0047] The amount of the alkoxysilyl group-containing compound added is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and even more preferably 0.3 parts by mass or more, relative to 100 parts by mass of the monomer. On the other hand, the amount of the alkoxysilyl group-containing compound added may be, for example, 5.0 parts by mass or less, 3.0 parts by mass or less, 2.0 parts by mass or less, or 1.0 part by mass or less.

[0048] It is preferable to polymerize the monomers in the presence of a polymerization initiator. Examples of the polymerization initiator include azoisobutyronitrile, methyl azoisobutyrate, azobisdimethylvaleronitrile, benzoyl peroxide, potassium persulfate, ammonium persulfate, benzophenone derivatives, phosphine oxide derivatives, benzoketone derivatives, phenylthioether derivatives, azide derivatives, diazo derivatives, and disulfide derivatives. These may be used alone or in combination of two or more.

[0049] The amount of the polymerization initiator added can be, for example, 0.01 to 5 parts by mass relative to 100 parts by mass of the monomer.

[0050] One example of a polymerization method is solution polymerization. Examples of solvents that can be used in solution polymerization include alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, ethylene glycol, and propylene glycol; ketones such as acetone and methyl ethyl ketone; ethers such as diethyl ether and tetrahydrofuran; aromatic hydrocarbon compounds such as benzene, toluene, and xylene; aliphatic hydrocarbon compounds such as n-hexane; alicyclic hydrocarbon compounds such as cyclohexane; acetate esters such as methyl acetate and ethyl acetate; and water. These solvents may be used alone or in combination of two or more. The monomer concentration, polymerization temperature, polymerization time, and the like can be appropriately set. The polymerization may be carried out under an inert gas. Examples of inert gases include nitrogen gas and argon gas.

[0051] The weight-average molecular weight of the betaine polymer is preferably 10,000 or more, and more preferably 50,000 or more. On the other hand, the weight-average molecular weight of the betaine polymer may be, for example, 1,000,000 or less, or 500,000 or less. The weight-average molecular weight of the betaine polymer is a value measured by gel permeation chromatography.

[0052] The content of the betaine polymer in the coating agent of this embodiment is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, and even more preferably 60% by mass or more, when the total content of the betaine polymer and the ionic liquid is taken as 100% by mass. A content of 30% by mass or more can form a coating film with even better hydrophilicity and slip-off properties. The content of the betaine polymer may be, for example, 70% by mass or more, or even 80% by mass or more. Meanwhile, the content of the betaine polymer in the coating agent of this embodiment is preferably 93% by mass or less, more preferably 90% by mass or less, even more preferably 87% by mass or less, and even more preferably 85% by mass or less, when the total content of the betaine polymer and the ionic liquid is taken as 100% by mass. A content of 93% by mass or less can further suppress or reduce excessive cracking in the coating film.

[0053] <1.2. Ionic Liquid> The coating agent of this embodiment contains an ionic liquid. Because the coating agent contains an ionic liquid, it is possible to suppress or reduce the occurrence of excessive cracks in the coating film. This will be explained below. Since betaine polymers contain monomer units containing a betaine structure, they tend to have high cohesive strength, and therefore the cohesive strength of the coating film also tends to be high. Therefore, cracks may occur in coating films containing betaine polymers. In contrast, according to this embodiment, the ionic liquid is able to interact closely with the betaine polymer, thereby alleviating the cohesive strength between the betaine polymers. Therefore, the coating agent of this embodiment can suppress or reduce the occurrence of excessive cracks in the coating film.

[0054] London dispersion term δ of Hansen solubility parameter (HSP) in ionic liquids ｄis 10.0 MPa １／２ Over 18.3 MPa １／２ and the dipole-dipole force term δ ｐ is 10.0 MPa １／２ Over 20.0 MPa １／２ is less than or equal to the hydrogen bond strength term δ ｈ is 14.0 MPa １／２ It is preferable that the London dispersion term δ of the ionic liquid is equal to or less than 1. This can suppress or reduce the cloudiness of the coating layer that may occur due to aggregation of the betaine polymer, and can further suppress or reduce the occurrence of cracks in the coating film. This will be explained below. ｄ is 10.0 MPa １／２ Over 18.3 MPa １／２ and the dipole-dipole force term δ ｐ is 10.0 MPa １／２ Over 20.0 MPa １／２ is less than or equal to the hydrogen bond strength term δ ｈ is 14.0 MPa １／２ Since the above ratio is below 1, this ionic liquid has excellent compatibility with betaine polymers, and therefore can suppress or reduce aggregation of the betaine polymers. As a result, it is possible to suppress or reduce cloudiness of the coating film that may occur due to aggregation of the betaine polymers, and it is also possible to further alleviate the cohesive force between the betaine polymers. Therefore, this ionic liquid can suppress or reduce cloudiness of the coating layer that may occur due to aggregation of the betaine polymers, and it is also possible to further suppress or reduce the occurrence of cracks in the coating film.

[0055] Here, the Hansen solubility parameter (HSP) refers to a vector parameter obtained by dividing the Hildebrand solubility parameter into three cohesive energy components: London dispersion force, dipole-dipole force, and hydrogen bonding force. Here, the component corresponding to the London dispersion force of the HSP is called the dispersion term δ ｄ , or the London dispersion force term δ ｄ The component corresponding to the dipole-dipole force of HSP is called the polar term δ ｐ , or the dipole-dipole force term δ ｐ The component corresponding to the hydrogen bonding strength of HSP is called the hydrogen bonding term δ ｈ , or hydrogen bond strength term δｈ It is sometimes called.

[0056] The HSP can be determined by the Hansen dissolving sphere method. In the Hansen dissolving sphere method, a sample (specifically, an ionic liquid) is first mixed with various solvents with known HSPs, and whether the sample is dissolved in each solvent is determined. Next, the London dispersion force term δ ｄ , dipole-dipole force term δ ｐ , and the hydrogen bond strength term δ ｈ In the three-dimensional space with the axis, the London dispersion force term δ ｄ , dipole-dipole force term δ ｐ , and the hydrogen bond strength term δ ｈ Based on the three-dimensional graph on which these are plotted, the smallest sphere, i.e., the Hansen dissolution sphere, is created, which includes the coordinates of the solvent in which the sample is dissolved (i.e., the good solvent) and does not include the coordinates of the solvent in which the sample is not dissolved (i.e., the poor solvent). The coordinates of the center of the Hansen dissolution sphere can be determined as the HSP of the sample. Specifically, the HSP can be determined by the method described in the Examples below.

[0057] London dispersion force term δ of HSP ｄ is 11.0 MPa １／２ More than 11.5 MPa is preferable. １／２ On the other hand, the London dispersion force term δ ｄ is, for example, 17.0 MPa １／２ It may be 16.0 MPa or less, １／２ It may be the following:

[0058] HSP dipole-dipole force term δ ｐ is, for example, 11.0 MPa １／２ or more, 13.0 MPa １／２ On the other hand, the dipole-dipole force term δ ｐ is, for example, 19.5 MPa １／２ or less, 19.0 MPa １／２ It may be the following:

[0059] HSP hydrogen bond term δ ｈ is 6.0 MPa １／２ More than 7.0 MPa is preferable. １／２On the other hand, the hydrogen bonding strength term δ ｈ is, for example, 13.5 MPa １／２ It may be 13.0 MPa or less, １／２ It may be the following:

[0060] Ionic liquids contain cations and anions. The combination of cations and anions is such that the ionic liquid has a melting point of 100°C or less. This is because ionic liquids are salts with a melting point of 100°C or less. Ionic liquids are sometimes called low-melting-point molten salts because they become liquid at a relatively low temperature compared to general inorganic salts. Examples of methods for synthesizing ionic liquids include anion exchange, acid ester, and neutralization.

[0061] The anion of the ionic liquid may be an inorganic anion or an organic anion. Specifically, the anion may be, for example, Cl. － ,Br － , I － , AlCl ４ － , Al ２ Cl ７ － , B.F. ４ － , P.F. ６ － , ClO ４ － , NO ３ － , C.H. ３ COO － , C.F. ３ COO － , C.H. ３ SO ３ － , C.F. ３ SO ３ － , C ４ F ９ SO ３ － , (CF ３ SO ２ ) ２ N － , (C ２ F ５ SO ２ ) ２ N －、(C ３ F ７ SO ２ ) ２ N － 、(C ４ F ９ SO ２ ) ２ N － 、(CF ３ SO ２ ) ３ C － 、AsF ６ － 、SbF ６ － 、NbF ６ － 、TaF ６ － 、F(HF) ｎ － 、(CN) ２ N － 、C ４ F ９ SO ３ － 、(C ２ F ５ SO ２ ) ２ N － 、C ３ F ７ COO － 、(CF ３ SO ２ )(CF ３ CO)N － 、C ９ H １９ COO － 、(CH ３ ) ２ PO ４ － 、(C ２ H ５ ) ２ PO ４ － 、C ２ H ５ OSO ３ － 、C ６ H １３ OSO ３ － 、C ８ H １７ OSO ３ － 、CH ３ (OC２ H ４ ) ２ OSO ３ － , C ６ H ４ (CH ３ ) SO ３ － , (C ２ F ５ ) ３ PF ３ － , C.H. ３ CH(OH)COO － , (FSO ２ ) ２ N － Among them, from the viewpoint of excellent compatibility with betaine polymers, (FSO ２ ) ２ N － , that is, bis(fluorosulfonyl)imide anion (hereinafter sometimes referred to as "FSI"), is preferred.

[0062] Examples of cations of ionic liquids include pyridinium cations such as 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-butyl-3-methylpyridinium cation, 1-butyl-4-methylpyridinium cation, 1-hexyl-3-methylpyridinium cation, and 1-butyl-3,4-dimethylpyridinium cation; pyrrolidinium cations such as 1,1-dimethylpyrrolidinium cation, 1-ethyl-1-methylpyrrolidinium cation, 1-methyl-1-propylpyrrolidinium cation, 1-methyl-1-butylpyrrolidinium cation, 1-methyl-1-pentylpyrrolidinium cation, 1-methyl-1-hexylpyrrolidinium cation, 1-methyl-1-heptylpyrrolidinium cation, 1-ethyl-1-propylpyrrolidinium cation, 1-ethyl-1-butylpyrrolidinium cation, 1-ethyl-1-pentylpyrrolidinium cation, 1-ethyl-1-hexylpyrrolidinium cation, 1-ethyl-1-heptylpyrrolidinium cation, 1,1-dipropylpyrrolidinium cation, 1-propyl-1-butylpyrrolidinium cation, 1,1-dibutylpyrrolidinium cation, and pyrrolidinium-2-one cation; 1-propylpiperidinium cation, 1-pentylpiperidinium cation, 1,1-dimethylpiperidinium cation, 1-methyl-1-ethylpiperidinium cation, 1-methyl-1-propylpiperidinium cation, 1-methyl-1-butylpiperidinium cation, 1-methyl-1-pentylpiperidinium cation, 1-methyl-1-hexylpiperidinium cation, 1-methyl-1-heptylpiperidinium cation, 1-ethyl-1-propylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, 1-ethyl-1-pentylpiperidinium cation, 1-ethyl-1-hexylpiperidinium cation, 1-ethyl-1-heptylpiperidinium cation, 1,1-dipropylpiperidinium cation, 1-propyl-1-butylpiperidinium cation, 1,piperidinium cations such as the 1-dibutylpiperidinium cation; cations having a pyrroline skeleton such as the 2-methyl-1-pyrroline cation; cations having a pyrrole skeleton such as the 1-ethyl-2-phenylindole cation, 1,2-dimethylindole cation, and 1-ethylcarbazole cation; morpholinium cations such as the N-ethyl-N-methylmorpholinium cation; 1,3-dimethylimidazolium cation, 1,3-diethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 1-butyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, 1-octyl-3-methylimidazolium cation, 1-decyl-3-methylimidazolium cation, 1-dodecyl-3-methylimidazolium cation, and 1-tetradecyl-3-methylimidazolium cation. imidazolium cations such as midazolium cation, 1,2-dimethyl-3-propylimidazolium cation, 1-ethyl-2,3-dimethylimidazolium cation, 1-butyl-2,3-dimethylimidazolium cation, 1-hexyl-2,3-dimethylimidazolium cation, 1-(2-methoxyethyl)-3-methylimidazolium cation, and 1,3-dimethyl-1,4,5,6-tetrahydropyrimidinium cation; Tetrahydropyrimidinium cations such as 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3,5-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation; dihydropyrimidinium cations such as 1,3-dimethyl-1,4-dihydropyrimidinium cation, 1,3-dimethyl-1,6-dihydropyrimidinium cation, 1,2,3-trimethyl-1,4-dihydropyrimidinium cation, 1,2,3-trimethyl-1,6-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,6-dihydropyrimidinium cation; 1-methylpyrazolium cation, 3-methylpyrazolium cation, 1-ethyl-2,3,pyrazolium cations such as 5-trimethylpyrazolium cation, 1-propyl-2,3,5-trimethylpyrazolium cation, 1-butyl-2,3,5-trimethylpyrazolium cation; pyrazolinium cations such as 1-ethyl-2-methylpyrazolinium cation, 1-ethyl-2,3,5-trimethylpyrazolinium cation, 1-propyl-2,3,5-trimethylpyrazolinium cation, 1-butyl-2,3,5-trimethylpyrazolinium cation; trialkylsulfonium cations such as trimethylsulfonium cation, triethylsulfonium cation, tributylsulfonium cation, trihexylsulfonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldecylsulfonium cation; tetraalkylphosphonium cations such as tetramethylphosphonium cation, tetraethylphosphonium cation, tetrabutylphosphonium cation, tetrahexylphosphonium cation, tetraoctylphosphonium cation, triethylmethylphosphonium cation, tributylethylphosphonium cation, trimethyldecylphosphonium cation, and tributyl-(2-methoxyethyl)phosphonium cation; Tetramethylammonium cation, tetraethylammonium cation, tetrabutylammonium cation, tetrapentylammonium cation, tetrahexylammonium cation, tetraheptylammonium cation, triethylmethylammonium cation, tributylethylammonium cation, trimethyldecylammonium cation, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium cation, glycidyltrimethylammonium cation, diallyldimethylammonium cation, N,N-dimethyl-N-ethyl-N-propylammonium cation, N,N-dimethyl-N-ethyl-N-butylammonium cation, N,N-dimethyl-N-ethyl-N-pentylammonium cation, N,N-dimethyl-N-ethyl-N-hexylammonium cation, N,N-dimethyl-N-ethyl-N-heptylammonium cation, N,N-dimethyl-N-ethyl-N-nonylammonium cation, N,N-dimethyl-N,N-dipropylammonium cation, N,N-diethyl-N-propyl-N-butylammonium cation, N,N-dimethyl-N-propyl-N-pentylammonium cation, N,N-dimethyl-N-propyl-N-hexylammonium cation, N,N-dimethyl-N-propyl-N-heptylammonium cation, N,N-dimethyl-N-butyl-N-hexylammonium cation, N,N-diethyl-N-butyl-N-heptylammonium cation, N,N-dimethyl-N-pentyl-N-hexylammonium cation, N,N-dimethyl-N,N-dihexylammonium cation, trimethylheptylammonium cation, N,N-diethyl-N-methyl-N-propylammonium cation, N,N-diethyl-N-methyl-N-pentylammonium cation, N,N-diethyl-N-methyl-N-heptylammonium cation ammonium cations such as N,N-diethyl-N-propyl-N-pentylammonium cation, triethylpropylammonium cation, triethylpentylammonium cation, triethylheptylammonium cation, N,N-dipropyl-N-methyl-N-ethylammonium cation, N,N-dipropyl-N-methyl-N-pentylammonium cation, N,N-dipropyl-N-butyl-N-hexylammonium cation, N,N-dipropyl-N,N-dihexylammonium cation, N,N-dibutyl-N-methyl-N-pentylammonium cation, N,N-dibutyl-N-methyl-N-hexylammonium cation, trioctylmethylammonium cation, N-methyl-N-ethyl-N-propyl-N-pentylammonium cation, and N,N-dimethyl-N,N-dihydroxyethylammonium cation; Among these, imidazolium cations and ammonium cations are preferred from the viewpoint of high compatibility with betaine polymers, and 1-ethyl-3-methylimidazolium cation (hereinafter sometimes referred to as "EMIM") and N,N-dimethyl-N,N-dihydroxyethylammonium cation (hereinafter sometimes referred to as "DDEA") are more preferred.

[0063] A specific example of an ionic liquid is a combination of 1-ethyl-3-methylimidazolium cation (i.e., EMIM) and bis(fluorosulfonyl)imide anion (i.e., FSI) from the viewpoint of excellent compatibility with the betaine polymer. On the other hand, a combination of an ammonium cation and bis(fluorosulfonyl)imide anion (i.e., FSI) is also preferred from the viewpoint of excellent compatibility with the betaine polymer. Of these, a combination of N,N-dimethyl-N,N-dihydroxyethylammonium cation (i.e., DDEA) and FSI is more preferred. The ionic liquids may be used alone or in combination of two or more.

[0064] 1.3 Leveling Agent The coating agent of this embodiment preferably contains a silicone-based leveling agent, which can effectively reduce the surface tension of the coating agent and the interfacial tension between the coating agent and the object to be coated (e.g., a substrate film), thereby suppressing the occurrence of cissing.

[0065] Examples of silicone leveling agents include polyether-modified silicone oil and polyglycerin-modified silicone oil, with polyether-modified silicone oil being preferred.

[0066] An example of the polyether-modified silicone oil is a compound represented by the following formula: ３ SiO(R ２ SiO) ｍ (RR ｅ SiO) ｎ SiR ３ Each R is independently an alkyl group having 1 to 4 carbon atoms. ｅ are each independently a group containing a polyether group (hereinafter sometimes referred to as an "introduced group").

[0067] Each R is independently an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group. Of these, it is preferable that all of the R groups are methyl groups.

[0068] R ｅ are each independently a group containing a polyether group. Examples of the polyether group include a polyethyleneoxy group and a polypropyleneoxy group. Examples of the polyether group include a group containing both an ethyleneoxy group (EO) and a propyleneoxy group (PO). In this case, the ethyleneoxy group (EO) and the propyleneoxy group (PO) may be arranged in a block form or randomly. Each R ｅ The polyether group may be linked to Si via a linking group. An example of the linking group is an alkylene group. The alkylene group may have, for example, 1 to 4 carbon atoms. Examples of alkylene groups having 1 to 4 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group.

[0069] The compound represented by this formula can be called a side-chain polyether-modified silicone oil. The side-chain polyether-modified silicone oil can include a main chain in which SiO is arranged repeatedly, a plurality of first side chains branched from the main chain, and a plurality of second side chains branched from the main chain. Each of the first side chains can be independently an alkyl group having 1 to 4 carbon atoms (see the description of R). Each of the second side chains can be independently a group containing a polyether group (R ｅ (See explanation below).

[0070] The content of the silicone-based leveling agent in the coating agent of this embodiment is preferably 0.02 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.10 parts by mass or more, and even more preferably 0.15 parts by mass or more, relative to 100 parts by mass of the betaine polymer. On the other hand, the content of the silicone-based leveling agent in the coating agent of this embodiment is preferably 3.0 parts by mass or less, more preferably 2.0 parts by mass or less, even more preferably 1.5 parts by mass or less, and even more preferably 1.0 part by mass or less.

[0071] The content of the silicone-based leveling agent is preferably 0.002% by mass or more, more preferably 0.005% by mass or more, relative to 100% by mass of the coating agent of this embodiment. On the other hand, the content of the silicone-based leveling agent may be, for example, 0.3% by mass or less, 0.2% by mass or less, 0.1% by mass or less, or 0.05% by mass or less.

[0072] <1.4. Solvent> The coating agent of this embodiment contains a solvent. Examples of the solvent include water, alcohol-based solvents, ketone-based solvents, amide-based solvents, and ether-based solvents. Of these, alcohol-based solvents are preferred. When the solvent contains an alcohol-based solvent, the occurrence of cissing can be further suppressed. In particular, cissing that can occur when a coating film is formed with the coating agent on a substrate film with relatively high hydrophobicity (for example, a polyolefin film such as a polyethylene film or a polypropylene film) can be further suppressed. Examples of alcohol-based solvents include methanol, isopropyl alcohol, n-butanol, diacetone alcohol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, and tertiary amyl alcohol. Water is also preferred as the solvent. In particular, it is more preferred that the solvent contains both water and an alcohol-based solvent.

[0073] The content of the alcohol-based solvent in the coating agent of this embodiment is preferably 5% by mass or more, more preferably 10% by mass or more, based on 100% by mass of the solvent. On the other hand, the content of the alcohol-based solvent may be, for example, 50% by mass or less, 30% by mass or less, or 25% by mass or less.

[0074] When the coating agent of this embodiment contains water and an alcohol-based solvent, the total content of water and alcohol-based solvent is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and even more preferably 97% by mass or more, based on 100% by mass of the solvent. The total content of water and alcohol-based solvent may be 98% by mass or more, 99% by mass or more, or even 100% by mass, based on 100% by mass of the solvent.

[0075] The content of the solvent is preferably 25% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, based on 100% by mass of the coating agent of this embodiment. On the other hand, the content of the solvent may be, for example, 99% by mass or less, or 95% by mass or less.

[0076] 1.5. Others The coating agent of the present embodiment may further contain a polymer other than the betaine polymer. The coating agent of the present embodiment may further contain an antioxidant, an ultraviolet absorber, a light stabilizer, a fluorine compound (e.g., a fluorine-based leveling agent), a surfactant, etc.

[0077] In the coating agent of this embodiment, the total content of the betaine polymer, ionic liquid, and solvent is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and even more preferably 97% by mass or more. This total content may be 98% by mass or more, 99% by mass or more, or even 100% by mass.

[0078] 1.6. Production Method and Use The coating agent of this embodiment can be produced, for example, by mixing a betaine polymer, an ionic liquid, and, if necessary, a solvent.

[0079] The coating agent of this embodiment can be suitably used to coat a substrate film. The substrate film can contain a resin. Examples of resins include polyolefin and polyester. Therefore, the substrate film may contain either a polyolefin or a polyester. Examples of polyolefins include polyethylene and polypropylene. Examples of polyesters include polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). PET may be a copolymerized PET. PEN may be a copolymerized PEN. Polyolefins are preferred because they have a low melting point and are easy to heat-seal into pouches. The substrate film may have a single-layer structure or a multi-layer structure. The substrate film may be surface-treated. Examples of surface treatments include corona treatment and plasma treatment.

[0080] The coating agent of this embodiment can be applied to a substrate film and then dried as necessary to form a coating film, i.e., a coating layer, on the substrate film. When the substrate film has been surface-treated, it is preferable to apply the coating agent to the surface-treated surface. Examples of application methods include gravure coating, roll coating, dip coating, brush coating, spray coating, bar coating, knife coating, die coating, and spin coating. To accelerate the drying of the coating agent, the substrate film to which the coating agent has been applied may be heated.

[0081] 2. Film and Pouch The film of this embodiment (hereinafter sometimes referred to as a "laminated film") includes a base film and a coating layer formed on the base film. As described above, the film of this embodiment can be obtained by applying the coating agent of this embodiment to the base film and then drying it as necessary. Note that, since the coating layer of the film of this embodiment has excellent hydrophilicity, it can be said that the deterioration of heat sealability that may occur due to the formation of the coating layer is not significant.

[0082] The thickness of the base film may be, for example, 10 μm or more, 15 μm or more, or 20 μm or more, while the thickness of the base film may be, for example, 1000 μm or less, 200 μm or less, 150 μm or less, or 100 μm or less.

[0083] The thickness of the coating layer is preferably 0.05 μm or more, more preferably 0.1 μm or more, and even more preferably 0.3 μm or more. On the other hand, the thickness of the coating layer is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less. The thinner the coating layer, the more likely it is that a deterioration in heat sealability caused by the coating layer can be avoided or reduced. In addition, the thinner the coating layer, the more likely it is that the coating layer can quickly form a lubricating surface, i.e., a surface with excellent sliding properties, when it comes into contact with a fluid.

[0084] The film of this embodiment may further include layers other than the substrate film and coating layer. Examples of layers other than the substrate film and coating layer include an adhesive layer, a nonwoven fabric layer, a printed layer, and an inorganic thin film layer. Examples of fibrous materials constituting the nonwoven fabric layer include cellulose fibers, polyamide fibers, vinylon fibers, polyester fibers, polyethylene fibers, polypropylene fibers, polyolefin fibers, and rayon fibers.

[0085] The film of this embodiment can be suitably used as a packaging film. Examples of packaging films include films for packaging medicines, food, and electronic components (for example, outer packaging films for lithium-ion batteries). Among these, the film can be particularly suitably used as a food packaging film.

[0086] The film of this embodiment can be suitably used as a film for pouches. The film of this embodiment can be particularly suitably used as a film for retort pouches and stoma pouches (i.e., pouches for stoma appliances). That is, the film of this embodiment can be particularly suitably used as a film for producing retort pouches and stoma pouches.

[0087] The pouch of this embodiment includes the above-mentioned film (i.e., a film including a base film and a coating layer formed on the base film). The pouch of this embodiment can be obtained, for example, by placing the coating layers of the above-mentioned films face to face and bonding them together by heat sealing. In this case, the coating layers of one film may be placed face to face and bonded together, or the coating layers of multiple films, for example, two films, may be placed face to face and bonded together. In the pouch of this embodiment, a coating layer is preferably disposed on the inner surface of the pouch. That is, the innermost layer of the pouch of this embodiment is preferably the coating layer.

[0088] The pouch of this embodiment may be, for example, a retort pouch or a stoma pouch. A stoma pouch, i.e., a pouch for a stoma appliance, is a bag that receives waste material discharged from a stoma. The stoma pouch may be provided with an opening (hereinafter, sometimes referred to as an "inlet") for receiving waste material. The stoma pouch may further be provided with an opening for discharging waste material accumulated in the stoma pouch. The stoma appliance may include a stoma pouch and a base plate provided on the stoma pouch. The base plate may be provided around the periphery of the inlet.

[0089] 3. Various modifications can be made to the above-described embodiment. Various modifications can be made to the above-described embodiment. For example, one or more of the following modifications can be selected and made to the above-described embodiment.

[0090] In the above-described embodiment, a configuration in which a coating agent is used to coat a substrate film has been described. However, the present embodiment is not limited to this configuration. For example, the coating agent may be used to coat a glass plate, a silicon wafer, a metal plate, or the like.

[0091] In the above embodiment, a configuration has been described in which the above film (i.e., a film including a base film and a coating layer formed on the base film) is produced, and then a pouch including a coating layer is produced. However, this embodiment is not limited to this configuration. For example, a pouch including a coating layer may be produced by coating at least a portion of the inner surface of a pouch not including a coating layer with the above coating agent. That is, a pouch including a coating layer may be produced by forming a coating layer with the above coating agent on at least a portion of the inner surface of a pouch not including a coating layer.

[0092] In the above embodiment, one or more of the above-described films are heat-sealed to form a pouch. However, the present embodiment is not limited to this configuration. For example, one or more of the above-described films may be cold-sealed using an adhesive or pressure-sensitive adhesive.

[0093] The present invention will be described in more detail below with reference to examples and comparative examples. Unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass".

[0094] <1. Raw materials> The following raw materials were used. Note that, hereinafter, polymers other than betaine acrylic polymers may be referred to as ionic functional group-containing polymers. Betaine monomer: 3-((2-(Methacryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate (manufactured by TCI) Radical generating initiator: VA-086 (manufactured by Fujifilm Wako Pure Chemical Industries) Chain transfer agent (reactive group introducing agent): 3-mercaptopropyltrimethoxysilane (manufactured by TCI) Ionic liquid: 1-ethyl-3-methyl-imidazorium bis(fluorosulfonyl)imide (manufactured by Tokyo Chemical Industry Co., Ltd.) Ionic liquid: 1-ethyl-3-methylimidazolium Acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) Ionic liquid: 1-ethyl-3-methylimidazolium Dimethyl Phosphate (manufactured by Merck) Leveling agent: KF-640 (manufactured by Shin-Etsu Chemical Co., Ltd., polyether-modified silicone oil)

[0095] 2. Hansen Solubility Parameters (HSP) The Hansen Solubility Parameters (HSP) of ionic liquids were determined using the solvents shown in Table 1. Specifically, the solvents used were water (HO), glycerol (GL), formamide (FA), thiodiethylene glycol (TDEG), diiodomethane (DIM), ethylene glycol (EG), 1,1,2,2-tetrabromoethane (TBE), 1-bromonaphthalene (BN), diethylene glycol (DEG), dimethylformamide (DMF), trichloroethylene (TCE), nitromethane (NM), trans-decahydronaphthalene (TDHN), and hexane (HX). Specifically, 2 mL of solvent was added to 0.2 g of ionic liquid under a nitrogen atmosphere, thoroughly stirred, and then allowed to stand for 24 hours. Next, the ionic liquid was visually evaluated for dissolution. This allowed us to determine whether the solvent was a good or poor solvent. The results were entered into the sphere program in Hansen Solubility Parameters in Practice (HSPiP) 5th Edition 5.0.13 software to determine the HSP of the ionic liquid. The London dispersion term (i.e., dispersion term) δ of the HSP thus determined was ｄ , dipole-dipole force term (i.e., polar term) δ ｐ , hydrogen bond strength term (i.e., hydrogen bond term) δ ｈ is shown in Table 2.

[0096] 3. Synthesis of Acrylic Polymer: 10 g of betaine monomer, 0.07 g of 3-mercaptopropyltrimethoxysilane as a chain transfer agent, and 10 g of purified water were added to a 100 mL multi-neck flask. Nitrogen gas was blown directly into the solution while stirring to remove as much oxygen as possible from the flask. Next, 0.01 g of radical-generating initiator was added, and the contents of the multi-neck flask were heated to 70°C in an oil bath and stirred for 4 hours while maintaining the temperature at 70°C. An additional 0.1 g of radical-generating initiator was then added, and the contents of the multi-neck flask were stirred for 4 hours while maintaining the temperature at 70°C. This yielded a polymer solution (solids concentration 51%). The weight-average molecular weight of the acrylic polymer (hereinafter referred to as "betaine acrylic polymer") contained in the polymer solution was measured using gel permeation chromatography (Tosoh HLC-8320GPC) and found to be 199,600.

[0097] 4. Preparation of Coating Liquid Coating liquids having the compositions shown in Table 3 were prepared.

[0098] 5. Preparation of Test Specimens 5.1. Examples 1-5 and Comparative Example 2 The coating solution was applied to a polypropylene film (Pylen P2161, 50 μm thick, manufactured by Toyobo Co., Ltd.) using a bar coater. Specifically, the coating solution was dropped onto the corona-treated surface of the polypropylene film, and then uniformly coated onto the polypropylene film using a bar coater. The polypropylene film coated with the coating solution was placed in a 60°C oven and heated for 72 hours. This resulted in a film (hereinafter sometimes referred to as a "laminated film") comprising a polypropylene film and a coating film formed thereon. The dry thickness of the coating film was approximately 0.7 μm. Test specimens were cut from the laminated film and used to evaluate various performance characteristics. 5.2. Comparative Example 1 Test specimens were cut from a commercially available stoma pouch (Cellcare® 1 TD, manufactured by Alcare Co., Ltd.) and used to evaluate various performance characteristics. Note that the side of this test specimen that was the inner surface of the stoma pouch will be referred to as "side I" below.

[0099] 6. Evaluation Method 6.1. Clouding of Coating Liquid The coating liquid was visually evaluated for cloudiness. Examples in which the coating liquid was not cloudy were indicated by ◯, and examples in which the coating liquid was cloudy were indicated by ×.

[0100] 6.2. Clouding of Coating Film Whether or not the coating film was clouded was evaluated visually. Examples in which the coating film was not clouded were indicated by ◯, and examples in which the coating film was clouded were indicated by ×.

[0101] 6.3. Cracks in the coating film The appearance of the coating film was visually evaluated according to the following criteria: A: No cracks B: Cracks are present, but the coating film is not peeling off near the cracks. In other words, there are no large cracks that lead to peeling of the coating film C: Cracks are present, and the coating film is peeling off near the cracks

[0102] 6.4. Sliding Property Approximately 100 μL of curry was drawn up from a commercially available 30 g pack of curry (Miyajima Shoyu) using a micropipette and dispensed onto the coating or I side of the test specimen. The test specimen was left standing vertically for 10 minutes, and the sliding distance of the curry was measured. Here, "sliding distance" refers to the distance over which the majority of the curry (approximately 90 μL or more) slid. A sliding distance of 2 cm or more is indicated by a circle, and a sliding distance of less than 2 cm is indicated by an X. Although curry is a food product, it can be considered as feces for the purpose of assessing sliding property. Because the properties of real feces vary from sample to sample, it is difficult to reproducibly evaluate sliding distance. On the other hand, because the properties of commercially available curry are more stable than those of real feces, using commercially available curry allows for more reproducible evaluation of sliding distance.

[0103] <6.5. Durability> After measuring the sliding distance, the curry was removed as much as possible from the test piece using a Pro Wipe. The sliding distance was then measured again using the procedure described above in <6.4. Sliding Property>. This time, the curry was dispensed onto the same location on the test piece. Examples where the sliding distance was 2 cm or more are indicated by a circle, and examples where the sliding distance was less than 2 cm are indicated by an x.

[0104] <6.6. Heat Sealing Properties> Two test pieces cut out from the laminated film were heat-sealed by heat sealing the coatings together or the I-sides together using a heat sealer (Fuji Impulse Poly Sealer (registered trademark) P-300) to obtain a heat-sealed sample. The heat sealing was performed by setting the heat sealer's heating time adjustment knob to 10, pushing down the pressure lever, and lifting the pressure lever after the heat sealer's cooling completion sound was heard, repeating this procedure twice. One test piece was held between the thumb and index finger of the right hand, and the other test piece was held between the thumb and index finger of the left hand, and the heat-sealed sample was pulled in a direction that separated the right and left hands by 180°. The heat sealability was then evaluated for appearance using the following criteria: ◯: No peeling occurred at the seal interface, and at least one test piece broke. ×: Peeling occurred at the seal interface.

[0105] 7. Results A table containing the results is shown below. In this table, the mass of the betaine acrylic polymer is the mass of the solids in the betaine acrylic polymer solution. The solvent amount in Table 3 is the combined amount of solvent derived from the betaine acrylic polymer solution and solvent not derived from it. The "mass ratio" in Table 3 refers to the mass of the ionic liquid relative to the mass of the solids in the betaine acrylic polymer solution. In other words, the mass ratio is: mass of the solids in the betaine acrylic polymer solution / mass of the ionic liquid. PP is a polypropylene (PP) film. PE is a polyethylene (PE) film. Durability was not evaluated in Examples 3 to 5 and Comparative Examples 1 and 2.

[0106] The laminated films produced in Examples 1 and 2 had no cracks in the coating and also exhibited excellent sliding properties. Regarding sliding properties, the sliding distance for Example 1 was 8 cm, and the sliding distance for Example 2 was 8 cm. Regarding durability, the sliding distance for Example 1 was 6 cm, and the sliding distance for Example 2 was 5 cm.

[0107] The laminated films produced in Examples 3 to 5 did not have any large cracks that would lead to peeling of the coating film, and furthermore, showed excellent sliding properties.

[0108] On the other hand, in Comparative Example 1, which used a commercially available stoma pouch, the sliding properties were poor. In other words, the curry did not slide down. In the laminated film produced in Comparative Example 2, large cracks occurred that led to peeling of the coating film.

[0109] INDUSTRIAL APPLICABILITY The present invention can provide coating agents, films, and pouches, and is therefore industrially applicable.

Claims

1. A coating agent comprising: a polymer including a monomer unit having a betaine structure; and an ionic liquid.

2. The polymer is obtained by polymerizing at least a monomer represented by formula I, In the formula I, R １ is a (meth)acryloylaminoalkyl group having an alkyl group with 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms, and R ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, or a (meth)acryloyloxyalkyl group having an alkyl group with 1 to 4 carbon atoms, and R ４ The coating agent according to claim 1, wherein is an alkylene group having 1 to 4 carbon atoms or an oxyalkylene group having 1 to 4 carbon atoms.

3. The coating agent according to claim 1, wherein the polymer contains at least one of a silanol group and an alkoxysilyl group.

4. The coating agent according to claim 1, further comprising a silicone-based leveling agent.

5. The coating agent according to claim 4, wherein the silicone leveling agent is a polyether-modified silicone oil.

6. The coating agent according to claim 1, further comprising an alcohol-based solvent.

7. The coating agent according to claim 1, further comprising water.

8. The coating agent according to claim 1, which is used to coat a substrate film.

9. A film comprising: a substrate film; and a coating layer formed on the substrate film using the coating agent according to claim 1.

10. The film according to claim 9, wherein the substrate film comprises at least one of a polyolefin and a polyester.

11. The film according to claim 9, which is used as a packaging film.

12. The film of claim 9, which is used as a film for a pouch.

13. A pouch comprising the film of claim 9.

14. The pouch of claim 13, which is a stoma pouch.

Images