Antibacterial agent

Abstract

To provide an antibacterial agent that enables a fixing object to be selected with a relatively high degree of freedom.SOLUTION: An antibacterial agent contains a secondary reaction product between a primary reaction product of a polyisocyanate compound having a plurality of isocyanate groups, a tertiary amino group-containing compound reactable with some of the isocyanate groups, and a blocker blocking the remainder of some of the isocyanate groups, and an acid. Relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocker, the tertiary amino group-containing compound is more than 1.5 mass%. At least some tertiary amino groups of the tertiary amino group-containing compound react with an acid to form a tertiary ammonium salt.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an antibacterial agent.

Background Art

[0002] Conventionally, as an antibacterial agent, a compound containing a quaternary ammonium salt has been known. Further, a method of fixing such an antibacterial agent to the surface of various articles has been known.

[0003] More specifically, a method has been proposed in which an article containing a resin component having a carboxyl group is brought into contact with a solution of an antibacterial agent containing an ethoxysilane-based quaternary ammonium salt to impart the ethoxysilane-based quaternary ammonium salt to the surface of the article (see, for example, Patent Document 1).

[0004] In this method, the antibacterial agent is fixed to the article by the reaction between the carboxyl group of the resin component having a carboxyl group and the ethoxysilane group of the ethoxysilane-based quaternary ammonium salt.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the method described in Patent Document 1, it is necessary to select a resin component having a carboxyl group as an article (object to be fixed), and it is also necessary to select an ethoxysilane-based quaternary ammonium salt as an antibacterial agent (fixative). Therefore, there is a problem that the degree of freedom in selecting an article (object to be fixed) is relatively low.

[0007] The present invention is an antibacterial agent capable of selecting an object to be fixed with a relatively high degree of freedom.

Means for Solving the Problems

[0008] The antibacterial agent of the present invention [1] contains a primary reaction product of a polyisocyanate compound having a plurality of isocyanate groups, a tertiary amino group-containing compound that reacts with a part of the plurality of isocyanate groups, and a blocking agent that blocks the remainder of the plurality of isocyanate groups with respect to the part, and a secondary reaction product of an acid that forms a tertiary ammonium salt with at least a part of the tertiary amino groups of the tertiary amino group-containing compound. The ratio of the tertiary amino group-containing compound to the total amount of the polyisocyanate compound, the tertiary amino group-containing compound, and the blocking agent exceeds 1.5% by mass.

[0009] The antibacterial agent according to the above [1], in which the polyisocyanate compound of the present invention [2] contains an aliphatic polyisocyanate derivative.

[0010] The antibacterial agent according to the above [1] or [2], in which the acid of the present invention [3] contains an organic acid.

Advantages of the Invention

[0011] The antibacterial agent of the present invention contains a primary reaction product of a polyisocyanate compound having a plurality of isocyanate groups, a tertiary amino group-containing compound that reacts with a part of the plurality of isocyanate groups, and a blocking agent that blocks the remainder of the plurality of isocyanate groups with respect to the part, and a secondary reaction product of an acid that reacts with at least a part of the tertiary amino groups of the tertiary amino group-containing compound to form a tertiary ammonium salt. The ratio of the tertiary amino group-containing compound to the total amount of the polyisocyanate compound, the tertiary amino group-containing compound, and the blocking agent exceeds a predetermined value.

[0012] That is, the antibacterial agent of the present invention contains a tertiary ammonium salt in a predetermined ratio. Therefore, the antibacterial agent of the present invention has excellent antibacterial properties. In particular, in the antibacterial agent of the present invention, the tertiary amino group-containing compound reacts with the polyisocyanate compound. And the tertiary amino group-containing compound forms a tertiary ammonium salt.

[0013] As a result, the antibacterial agent of the present invention exhibits superior antibacterial properties compared to cases where a tertiary amino group-containing compound forms a tertiary ammonium salt on its own without reacting with a polyisocyanate compound.

[0014] Furthermore, the antibacterial agent of the present invention contains isocyanate groups blocked by a blocking agent, in addition to tertiary ammonium salts. Therefore, by deblocking the blocking agent, the isocyanate groups can be subjected to chemical reactions and can be easily reacted with various resins (immobilized materials). As a result, the antibacterial agent of the present invention allows for the selection of immobilized materials with a relatively high degree of freedom, enabling the immobilization of antibacterial tertiary ammonium salts in resins. [Modes for carrying out the invention]

[0015] The antibacterial agent of the present invention contains a tertiary ammonium salt-containing blocked isocyanate.

[0016] A tertiary ammonium salt-containing block isocyanate is a compound that contains one or more tertiary ammonium salts and one or more block isocyanate groups in its molecule.

[0017] A tertiary ammonium salt-containing block isocyanate can be obtained, for example, by the reaction of a tertiary amino group-containing block isocyanate with an acid.

[0018] More specifically, tertiary ammonium salt-containing block isocyanates are formed by converting the tertiary amino groups in tertiary amino group-containing block isocyanates into tertiary ammonium salts using an acid.

[0019] A tertiary amino group-containing blocked isocyanate is a compound that contains one or more tertiary amino groups and one or more blocked isocyanate groups in its molecule.

[0020] More specifically, a tertiary amino group-containing blocked isocyanate is a reaction product (primary reaction product) of a polyisocyanate compound having multiple isocyanate groups, a tertiary amino group-containing compound that reacts with some of the multiple isocyanate groups, and a blocking agent that blocks the remainder of the multiple isocyanate groups.

[0021] Furthermore, tertiary ammonium salt-containing block isocyanates are reaction products (secondary reaction products) of tertiary amino group-containing block isocyanates (the primary reaction product described above) and acids.

[0022] (1) Polyisocyanate compounds Examples of polyisocyanate compounds include polyisocyanate monomers and polyisocyanate derivatives.

[0023] Examples of polyisocyanate monomers include aliphatic polyisocyanates, aromatic polyisocyanates, and aromatic aliphatic polyisocyanates.

[0024] Examples of aliphatic polyisocyanates include ethylene diisocyanate, trimethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and 2,6-diisocyanate methyl caproate.

[0025] In addition, alicyclic polyisocyanate monomers can also be cited as examples of aliphatic polyisocyanate monomers.

[0026] Examples of alicyclic polyisocyanate monomers include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, methylenebis(cyclohexyl isocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, norbornane diisocyanate, and bis(isocyanatomethyl)cyclohexane.

[0027] Examples of aromatic polyisocyanates include tolylene diisocyanate, phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, diphenylmethane diisocyanate, 4,4'-toluidine diisocyanate, and 4,4'-diphenyl ether diisocyanate.

[0028] Examples of aromatic aliphatic polyisocyanates include xylylene diisocyanate, tetramethyl xylylene diisocyanate, and ω,ω'-diisocyanate-1,4-diethylbenzene.

[0029] Polyisocyanate derivatives are derived from the polyisocyanate monomers described above. Examples of polyisocyanate derivatives include isocyanurate-modified derivatives, iminooxadiazinedione-modified derivatives, triol adducts, allophanate-modified derivatives, biuret-modified derivatives, urea-modified derivatives, oxadiazinetrione-modified derivatives, carbodiimide-modified derivatives, uretdione-modified derivatives, and uretonimine-modified derivatives.

[0030] Polyisocyanate compounds can be used alone or in combination of two or more types. Preferably, the polyisocyanate compound includes a polyisocyanate derivative, and more preferably consists of a polyisocyanate derivative.

[0031] Preferably, polyisocyanate derivatives include aliphatic polyisocyanate derivatives derived from aliphatic polyisocyanates, more preferably isocyanurate-modified aliphatic polyisocyanates, and most preferably isocyanurate-modified 1,6-hexamethylene diisocyanate.

[0032] The average number of functional groups in the isocyanate groups of a polyisocyanate compound is, for example, 2 or more, preferably 2.5 or more. Alternatively, the average number of functional groups in the isocyanate groups of a polyisocyanate compound is, for example, 4 or less, preferably 3.5 or less.

[0033] The isocyanate group content (NCO%) in the polyisocyanate compound is, for example, 5% by mass or more, preferably 7% by mass or more. Alternatively, the isocyanate group content (NCO%) in the polyisocyanate compound is, for example, 30% by mass or less, preferably 25% by mass or less.

[0034] Furthermore, the polyisocyanate compound may be modified with a hydrophilic compound containing an active hydrogen group. In other words, the polyisocyanate compound can also contain both cationic and nonionic hydrophilic groups.

[0035] Hydrophilic compounds have both active hydrogen groups and hydrophilic groups. Examples of hydrophilic compounds include nonionic hydrophilic compounds, and preferably polyoxyethylene compounds. Polyoxyethylene compounds have at least three consecutive oxyethylene groups.

[0036] Examples of polyoxyethylene compounds include polyols containing polyoxyethylene groups, polyamines containing polyoxyethylene groups, single-ended polyoxyethylene glycols, and single-ended polyoxyethylenediamines.

[0037] Polyoxyethylene compounds can be used alone or in combination of two or more types.

[0038] The polyoxyethylene compound preferably comprises a single-ended polyoxyethylene glycol, and more preferably a monoalkoxy polyoxyethylene glycol.

[0039] One end of a monoalkoxypolyoxyethylene glycol is encapsulated with, for example, an alkyl group having 1 to 20 carbon atoms. The other end of the monoalkoxypolyoxyethylene glycol has a hydroxyl group.

[0040] Examples of monoalkoxypolyoxyethylene glycols include methoxypolyoxyethylene glycol and ethoxypolyoxyethylene glycol, with methoxypolyoxyethylene glycol being preferred.

[0041] The number-average molecular weight of polyoxyethylene compounds is, for example, 200 or more, preferably 400 or more. Alternatively, the number-average molecular weight of polyoxyethylene compounds is, for example, 2000 or less, preferably 1500 or less. The number-average molecular weight of polyoxyethylene compounds can be measured by gel permeation chromatography.

[0042] If the polyisocyanate compound is modified with a hydrophilic compound, for example, the polyisocyanate monomer and / or polyisocyanate derivative described above is reacted with the hydrophilic compound described above in a proportion that leaves free isocyanate groups intact.

[0043] The ratio of active hydrogen groups of the hydrophilic compound to 100 moles of isocyanate groups of the polyisocyanate compound before modification is, for example, 0.5 moles or more, preferably 1 mole or more. Furthermore, the ratio of active hydrogen groups of the hydrophilic compound to 100 moles of isocyanate groups of the polyisocyanate compound before modification is, for example, 10 moles or less, preferably 5 moles or less.

[0044] (2) Compounds containing tertiary amino groups A tertiary amino group-containing compound has both an isocyanate reactive group and a tertiary amino group.

[0045] The isocyanate reactive group is a functional group that reacts with some of the multiple isocyanate groups of the polyisocyanate compound described above.

[0046] An isocyanate reactive group is a group that is active towards the isocyanate group of a polyisocyanate compound. The isocyanate reactive group is not particularly limited, but examples include active hydrogen groups and blocked groups. Examples of active hydrogen groups include hydroxyl groups, primary amino groups, and secondary amino groups. Examples of blocked groups include guanidine groups, imidazole groups, alcohol groups, phenol groups, active methylene groups, amine groups, imine groups, oxime groups, carbamic acid groups, urea groups, acid amide groups, acid imide groups, triazole groups, pyrazole groups, mercaptan groups, bisulfites, imidazoline groups, and pyrimidine groups. These can be used individually or in combination of two or more.

[0047] Preferably, the isocyanate reaction group is a blocked group, and more preferably, a guanidine group.

[0048] The tertiary amino group is a functional group that forms a tertiary ammonium salt (described later) without reacting with the isocyanate group of the polyisocyanate compound mentioned above.

[0049] More specifically, a tertiary amino group is an amino group in which three atoms other than hydrogen atoms are single-bonded to one nitrogen atom. In other words, an amino group in which atoms other than hydrogen atoms are double-bonded or triple-bonded to one nitrogen atom is not a tertiary amino group. Note that tertiary amino groups may also be included in heterocyclic structures.

[0050] More specifically, examples of tertiary amino group-containing compounds include guanidine compounds represented by the following general formula (1). [ka] (wherein, R ,

[0054] ~R 5 represents a hydrocarbon group having 1 to 12 carbon atoms or a hydrogen atom. However, both R 1 and R 2 represent hydrocarbon groups having 1 to 12 carbon atoms, and / or both R 4 and R 5 represent hydrocarbon groups having 1 to 12 carbon atoms. Further, R 1 and R 3 may be bonded to each other to form a heterocyclic ring. Also, R 4 and R 1 may be bonded to each other to form a heterocyclic ring. Also, R 5 and R 3 may be bonded to each other to form a heterocyclic ring.) In the above general formula (1), R 1 ~R 5 may be the same as or different from each other. R 1 ~R 5 represent a hydrocarbon group having 1 to 12 carbon atoms or a hydrogen atom.

[0051] However, both R 1 and R 2 represent hydrocarbon groups having 1 to 12 carbon atoms, and / or both R 4 and R 5 represent hydrocarbon groups having 1 to 12 carbon atoms. Thereby, the guanidine compound represented by the general formula (1) contains at least one tertiary amino group.

[0052] Examples of the hydrocarbon group having 1 to 12 carbon atoms represented by R 1 ~R 5 include an alkyl group having 1 to 12 carbon atoms and an aryl group having 6 to 12 carbon atoms.

[0053] Examples of the alkyl group having 1 to 12 carbon atoms include a linear alkyl group having 1 to 12 carbon atoms and a cyclic alkyl group having 3 to 12 carbon atoms.

[0054] Examples of linear alkyl groups having 1 to 12 carbon atoms include straight-chain or branched linear alkyl groups having 1 to 12 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, tert-pentyl, hexyl, heptyl, octyl, nonyl, isononyl, decyl, undecyl, and dodecyl.

[0055] Examples of cyclic alkyl groups having 3 to 12 carbon atoms include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl.

[0056] Examples of aryl groups having 6 to 12 carbon atoms include phenyl, tolyl, xylyl, naphthyl, azulenyl, and biphenyl.

[0057] Hydrocarbon groups with 1 to 12 carbon atoms are R 1 ~R 5 In this context, they may be identical or different from one another.

[0058] Also, R 1 and R 3 These elements can bond to each other to form heterocycles.

[0059] R 1 and R 3 The heteroring formed by the bonding of these elements is a nitrogen-containing heteroring having a -N=CN- structure, such as a 3-20 membered heteroring, preferably a 3-10 membered heteroring, more preferably a 3-8 membered heteroring, and even more preferably a 5-7 membered heteroring. The heteroring may also be monocyclic, or polycyclic, where multiple monocyclic rings share one side. Furthermore, the heteroring may be a conjugated heteroring.

[0060] Also, R 4 and R 1 These can bond to each other to form a heterocycle. Furthermore, R 5 and R3 These elements can bond to each other to form a heterocycle.

[0061] Also, R 1 , R 3 , R 4 and R 5 The heteroring formed from may be a polycyclic ring in which multiple monorings share one side. In this case, the heteroring formed is a nitrogen-containing heteroring having a -N=CN- structure, and examples include a 6-20 membered heteroring, preferably a 6-15 membered heteroring, more preferably a 6-12 membered heteroring, and even more preferably a 10-12 membered heteroring. The heteroring may also be a conjugated heteroring. Note that R 1 , R 3 , R 4 and R 5 When R forms a heterocycle, 2 Preferably, this represents a hydrogen atom. Specifically, such a heterocyclic structure is a triazabicyclo ring structure.

[0062] In the above general formula (1), R 1 ~R 5 Preferably, it represents a hydrocarbon group or hydrogen atom having 1 to 12 carbon atoms, more preferably an alkyl group or hydrogen atom having 1 to 12 carbon atoms, and even more preferably a chain alkyl group or hydrogen atom having 1 to 12 carbon atoms.

[0063] However, R 1 and R 2 Both of these represent hydrocarbon groups with 1 to 12 carbon atoms, and / or R 4 and R 5 Both of these represent hydrocarbon groups with 1 to 12 carbon atoms.

[0064] Particularly preferred is the above general formula (1), R 1 , R 2 , R 4 and R 5 R represents a chain-like alkyl group having 1 to 12 carbon atoms. 3 This represents a hydrogen atom.

[0065] Examples of guanidine compounds represented by the above general formula (1) include 3,3-dialkylguanidine, 1,1,3,3-tetraalkylguanidine, and 1,5,7-triazabicyclo[4.4.0]deca-5-ene.

[0066] The guanidine compounds shown in the above general formula (1) can be used alone or in combination of two or more.

[0067] The tertiary amino group-containing compounds are not limited to the guanidine compounds described above. Examples of tertiary amino group-containing compounds include, in addition to the guanidine compounds described above, N-dimethylaminoethanol (DMAE), N-methyldiethanolamine (MDEA), N-methylpiperazine (MPZ), N-methylhomopiperazine (MHPZ), 1,8-diazabicyclo[5.4.0]-7-undecene (DBU), N,N,N'-trimethylethylenediamine (TMEDA), and 1,5,7-triazabicyclo[4.4.0]deca-5-ene (TABD).

[0068] The tertiary amino group-containing compound can be used alone or in combination of two or more types. Preferably, the tertiary amino group-containing compound is the guanidine compound shown in the general formula (1) above. If the tertiary amino group-containing compound includes the guanidine compound shown in the general formula (1) above, an antibacterial agent with excellent water dispersibility and antibacterial properties can be obtained.

[0069] More preferably, the tertiary amino group-containing compound is 1,1,3,3-tetraalkylguanidine, and more preferably, 1,1,3,3-tetramethylguanidine (TMG). That is, the tertiary amino group-containing compound more preferably contains 1,1,3,3-tetramethylguanidine, and even more preferably consists of 1,1,3,3-tetramethylguanidine. If the tertiary amino group-containing compound contains 1,1,3,3-tetramethylguanidine (TMG), an antibacterial agent with particularly excellent water dispersibility and antibacterial properties can be obtained.

[0070] In a tertiary amino group-containing compound, if the isocyanate reactive group is a blocking group (preferably a guanidine group), the tertiary amino group-containing compound blocks and inactivates the isocyanate group of the polyisocyanate compound.

[0071] Furthermore, if the isocyanate reactive group is a blocked group (guanidine group), the tertiary amino group-containing compound can be deblocked by heating, and the isocyanate group can be regenerated.

[0072] In such cases, the dissociation temperature of the tertiary amino group-containing compound (the dissociation temperature of the tertiary amino group-containing compound when the isocyanate reactive group is a blocking group (hereinafter the same)) is preferably higher than the dissociation temperature of the blocking agent described later.

[0073] If the dissociation temperature of the tertiary amino group-containing compound is higher than the dissociation temperature of the blocking agent described later, the tertiary amino group and the tertiary ammonium salt (described later) will not dissociate even when the blocking agent dissociates, and will maintain their bond with the polyisocyanate compound.

[0074] Therefore, if a resin (described later) is formed by the dissociation of the blocking agent, the tertiary ammonium salt can be immobilized in that resin.

[0075] More specifically, the dissociation temperature of a tertiary amino group-containing compound is, for example, 60°C or higher, preferably 100°C or higher. Alternatively, the dissociation temperature of a tertiary amino group-containing compound is, for example, 200°C or lower, preferably 180°C or lower, and even more preferably 160°C or lower.

[0076] The dissociation temperature of the tertiary amino group-containing compound can be measured in the same manner as the dissociation temperature of the blocking agent described later (the same applies hereafter).

[0077] Furthermore, when the tertiary amino group in a tertiary amino group-containing compound becomes a tertiary ammonium salt (described later), the dissociation temperature of the tertiary ammonium salt (described later) is higher than or equal to the dissociation temperature of the tertiary amino group-containing compound. More specifically, the dissociation temperature of the tertiary ammonium salt (described later) is 0°C to 30°C higher than the dissociation temperature of the tertiary amino group-containing compound.

[0078] (3) Blocking agents The blocking agent can block and inactivate (block isocyanate) isocyanate groups. Furthermore, the blocking agent can be deblocked by heating, allowing for the regeneration of isocyanate groups. Additionally, the blocking agent does not contain tertiary amino groups and is therefore distinct from the aforementioned tertiary amino group-containing compounds.

[0079] More specifically, the blocking agent has an isocyanate reactant group for reacting with the remainder of the multiple isocyanate groups of the polyisocyanate compound. The remainder refers to the portion of the multiple isocyanate groups of the polyisocyanate compound that reacts with the tertiary amino group-containing compound mentioned above.

[0080] Examples of blocking agents include imidazole compounds, alcohol compounds, phenolic compounds, active methylene compounds, primary and secondary amine compounds, imine compounds, oxime compounds, carbamic acid compounds, urea compounds, acid amide compounds, acid imide compounds, triazole compounds, pyrazole compounds, mercaptan compounds, bisulfites, imidazoline compounds, and pyrimidine compounds.

[0081] Examples of imidazole compounds include imidazole, benzimidazole, 2-methylimidazole, 4-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, and 2-amineimidazole.

[0082] Examples of alcohol compounds include methanol, ethanol, 2-propanol, n-butanol, s-butanol, 2-ethylhexyl alcohol, 1-octanol, 2-octanol, cyclohexyl alcohol, ethylene glycol, benzyl alcohol, 2,2,2-trifluoroethanol, 2,2,2-trichloroethanol, 2-(hydroxymethyl)furan, 2-methoxyethanol, methoxypropanol, 2-ethoxyethanol, n-propoxyethanol, 2-butoxyethanol, and 2-ethoxyethoxyethanol. Examples include ethanol, 2-ethoxybutoxyethanol, butoxyethoxyethanol, 2-butoxyethylethanol, 2-butoxyethoxyethanol, N,N-dibutyl-2-hydroxyacetamide, N-hydroxysuccinimide, N-morpholineethanol, 2,2-dimethyl-1,3-dioxolane-4-methanol, 3-oxazolidineethanol, 2-hydroxymethylpyridine, furfuryl alcohol, 12-hydroxystearic acid, triphenylsilanol, and 2-hydroxyethyl methacrylate.

[0083] Examples of phenolic compounds include phenol, cresol, ethylphenol, n-propylphenol, isopropylphenol, n-butylphenol, s-butylphenol, t-butylphenol, n-hexylphenol, 2-ethylhexylphenol, n-octylphenol, n-nonylphenol, di-n-propylphenol, diisopropylphenol, isopropyl cresol, di-n-butylphenol, di-s-butylphenol, di-t-butylphenol, di-n-octylphenol, di-2-ethylhexylphenol, and di-n-nonyl Examples include phenols, nitrophenols, bromophenols, chlorophenols, fluorophenols, dimethylphenols, styrene-phenols, methyl salicylates, methyl 4-hydroxybenzoate, benzyl 4-hydroxybenzoate, ethylhexyl hydroxybenzoate, 4-[(dimethylamino)methyl]phenol, 4-[(dimethylamino)methyl]nonylphenol, bis(4-hydroxyphenyl)acetic acid, 2-hydroxypyridine, 2-hydroxyquinoline, 8-hydroxyquinoline, 2-chloro-3-pyridinol, and pyridine-2-thiol.

[0084] Examples of active methylene compounds include meldramic acid, dialkyl malonate, alkyl acetoacetate, 2-acetoacetoxyethyl methacrylate, acetylacetone, and ethyl cyanoacetate. Examples of dialkyl malonates include dimethyl malonate, diethyl malonate, di-n-butyl malonate, di-t-butyl malonate, di-2-ethylhexyl malonate, methyl n-butyl malonate, ethyl n-butyl malonate, methyl s-butyl malonate, ethyl s-butyl malonate, methyl t-butyl malonate, ethyl t-butyl malonate, diethyl methylmalonate, dibenzyl malonate, diphenyl malonate, benzylmethyl malonate, ethylphenyl malonate, t-butylphenyl malonate, and isopropylidene malonate. Examples of alkyl acetoacetates include methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, isopropyl acetoacetate, n-butyl acetoacetate, t-butyl acetoacetate, benzyl acetoacetate, and phenyl acetoacetate.

[0085] Examples of primary and secondary amine compounds include dibutylamine, diphenylamine, aniline, N-methylaniline, carbazole, bis(2,2,6,6-tetramethylpiperidinyl)amine, di-n-propylamine, diisopropylamine, isopropylethylamine, 2,2,4-trimethylhexamethyleneamine, 2,2,5-trimethylhexamethyleneamine, N-isopropylcyclohexylamine, dicyclohexylamine, and bis(3,5,5-trimethylcyclohexyl)amine. Examples include piperidine, 2,6-dimethylpiperidine, t-butylmethylamine, t-butylethylamine, t-butylpropylamine, t-butylbutylamine, t-butylbenzylamine, t-butylphenylamine, 2,2,6-trimethylpiperidine, 2,2,6,6-tetramethylpiperidine, (dimethylamino)-2,2,6,6-tetramethylpiperidine, 2,2,6,6-tetramethyl-4-piperidine, 6-methyl-2-piperidine, and 6-aminocaproic acid.

[0086] Examples of imine compounds include ethyleneimine, polyethyleneimine, and 1,4,5,6-tetrahydropyrimidine.

[0087] Examples of oxime compounds include formaldehyde oxime, acetaldehyde oxime, acetooxime, methyl ethyl ketoxime, cyclohexanone oxime, diacetyl monooxime, benzophenooxime, 2,2,6,6-tetramethylcyclohexanone oxime, diisopropyl ketone oxime, methyl t-butyl ketone oxime, diisobutyl ketone oxime, methyl isobutyl ketone oxime, methyl isopropyl ketone oxime, methyl 2,4-dimethylpentyl ketone oxime, methyl 3-ethylheptyl ketone oxime, methyl isoamyl ketone oxime, n-amyl ketone oxime, 2,2,4,4-tetramethyl-1,3-cyclobutanedione monooxime, 4,4'-dimethoxybenzophenone oxime, and 2-heptanone oxime.

[0088] An example of a carbamic acid compound is phenyl N-phenylcarbamate.

[0089] Examples of urea-based compounds include urea, thiourea, and ethyleneurea.

[0090] Acid amide compounds are, in other words, lactam compounds. Examples of acid amide compounds include acetanilide, N-methylacetamide, acetic acid amide, ε-caprolactam, δ-valerolactam, γ-butyrolactam, pyrrolidone, 2,5-piperazinedione, and laurolactam.

[0091] Examples of acid-imide compounds include succinimide, maleimide, and phthalimide.

[0092] Examples of triazole compounds include 1,2,4-triazole and benzotriazole.

[0093] Examples of pyrazole compounds include pyrazole, 3-methylpyrazole, 3-methyl-5-phenylpyrazole, 3,5-diphenylpyrazole, 4-benzyl-3,5-dimethylpyrazole, 4-nitro-3,5-dimethylpyrazole, 4-bromo-3,5-dimethylpyrazole, and 3,5-dialkylpyrazole. 3,5-dialkylpyrazoles do not have substituents at the 4-position of the pyrazole ring. Examples of 3,5-dialkylpyrazoles include 3,5-dimethylpyrazole, 3,5-diisopropylpyrazole, and 3,5-di-t-butylpyrazole.

[0094] Examples of mercaptan compounds include butyl mercaptan, dodecyl mercaptan, and hexyl mercaptan.

[0095] Examples of bisulfites include sodium bisulfite.

[0096] Examples of imidazoline compounds include 2-methylimidazoline and 2-phenylimidazoline.

[0097] Examples of pyrimidine compounds include 2-methyl-1,4,5,6-tetrahydropyrimidine.

[0098] Furthermore, the blocking agents are not limited to those mentioned above. Examples of blocking agents include benzoxazolone, isopropyl anhydride, and tetrabutylphosphonium acetate.

[0099] These blocking agents can be used alone or in combination of two or more types.

[0100] The blocking agent preferably contains a pyrazole compound, and more preferably consists of a pyrazole compound. Preferred pyrazole compounds include 3,5-diphenylpyrazole and 3,5-dialkylpyrazole, more preferably 3,5-dialkylpyrazole, and even more preferably 3,5-dimethylpyrazole.

[0101] Furthermore, the dissociation temperature of the blocking agent is preferably lower than that of the tertiary amino group-containing compound.

[0102] If the dissociation temperature of the blocking agent is lower than that of the tertiary amino group-containing compound, the blocking agent can be dissociated while suppressing the dissociation of the tertiary amino group and the tertiary ammonium salt (described later).

[0103] Therefore, if a resin (described later) is formed by the dissociation of the blocking agent, a tertiary ammonium salt can be immobilized in that resin.

[0104] More specifically, the dissociation temperature of the blocking agent is, for example, 50°C or higher. Alternatively, the dissociation temperature of the blocking agent may be, for example, 150°C or lower, preferably 140°C or lower, and even more preferably 130°C or lower.

[0105] Furthermore, the difference between the dissociation temperature of the blocking agent and the dissociation temperature of the tertiary amino group-containing compound is, for example, 1°C or more, preferably 10°C or more. Also, the difference between the dissociation temperature of the blocking agent and the dissociation temperature of the tertiary amino group-containing compound is, for example, 50°C or less, preferably 40°C or less.

[0106] The dissociation temperature of the blocking agent can be measured by the following method (the same applies hereafter).

[0107] Blocked isocyanate, in which isocyanate groups are blocked by a blocking agent, is coated onto a silicon wafer, and the temperature at which the isocyanate groups regenerate is observed by IR measurement while heating. This allows for the measurement of the dissociation temperature of the blocking agent. If necessary, the blocked isocyanate is mixed with a polyol, the mixture is coated onto a silicon wafer, and the temperature at which the hydroxyl groups of the polyol compound react is observed by IR measurement while heating. This allows for the measurement of the dissociation temperature of the blocking agent.

[0108] (4) Acid

[0109] Examples of acids include organic acids and inorganic acids. The acid preferably contains an organic acid, and more preferably consists of an organic acid. When the acid contains an organic acid, an antimicrobial agent with excellent storage stability is obtained.

[0110] Examples of organic acids include carboxylic acids having 2 or 3 carbon atoms and carboxylic acids having 4 or more carbon atoms, with carboxylic acids having 2 or 3 carbon atoms being preferred. Examples of carboxylic acids having 2 or 3 carbon atoms include acetic acid, propionic acid, and lactic acid. In other words, the acid is more preferably at least one organic acid selected from the group consisting of acetic acid, propionic acid, and lactic acid. The acid can be used alone or in combination of two or more types.

[0111] (5) Manufacturing of antimicrobial agents The manufacturing method for antibacterial agents will be described in detail below.

[0112] To manufacture the antibacterial agent, first, a polyisocyanate compound is reacted with a tertiary amino group-containing compound and a blocking agent. This produces a tertiary amino group-containing blocked isocyanate as the primary reaction product (primary reaction step). Next, the tertiary amino group of the tertiary amino group-containing blocked isocyanate is reacted with an acid. This forms a tertiary ammonium base-containing blocked isocyanate as the secondary reaction product (secondary reaction step).

[0113] More specifically, the polyisocyanate compound is first reacted with a tertiary amino group-containing compound and a blocking agent (first reaction step).

[0114] In the reaction step, the tertiary amino group-containing compound reacts with a portion of the isocyanate groups of the polyisocyanate compound. Additionally, the blocking agent reacts with the remainder of the isocyanate groups of the polyisocyanate compound. Note that "part" and "remainder" are determined relatively. That is, the blocking agent may react with a portion of the isocyanate groups of the polyisocyanate compound, and the tertiary amino group-containing compound may react with the remainder of the isocyanate groups.

[0115] In the reaction step, the proportion (by mass) of the polyisocyanate compound relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocking agent is, for example, 40% by mass or more, preferably 50% by mass or more. Alternatively, the proportion of the polyisocyanate compound relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocking agent is, for example, 80% by mass or less, preferably 70% by mass or less.

[0116] Furthermore, the proportion (by mass) of the tertiary amino group-containing compound relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocking agent exceeds 1.5% by mass, preferably 1.9% by mass or more, more preferably 2.0% by mass or more, even more preferably 5.0% by mass or more, even more preferably 10.0% by mass or more, even more preferably 20.0% by mass or more, and particularly preferably 30.0% by mass or more. Also, the proportion of the tertiary amino group-containing compound relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocking agent is, for example, 70.0% by mass or less, preferably 60.0% by mass or less, more preferably 50.0% by mass or less, and even more preferably 40.0% by mass or less.

[0117] Furthermore, the proportion of the blocking agent (by mass) relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocking agent is, for example, 1% by mass or more, preferably 10% by mass or more. Also, the proportion of the blocking agent relative to the total amount of the polyisocyanate compound, tertiary amino group-containing compound, and blocking agent is, for example, 60% by mass or less, preferably 50% by mass or less.

[0118] Furthermore, the ratio of the tertiary amino group-containing compound to the blocking agent that binds to the polyisocyanate compound is appropriately set according to the purpose and application.

[0119] For example, the amount of the tertiary amino group-containing compound is, for example, 5 mol% or more, preferably 10 mol% or more, relative to the total amount (moles) of the tertiary amino group-containing compound and the blocking agent. Also, the amount of the tertiary amino group-containing compound is, for example, 50 mol% or less, preferably 40 mol% or less, relative to the total amount (moles) of the tertiary amino group-containing compound and the blocking agent.

[0120] Furthermore, the amount of the blocking agent relative to the total amount (in moles) of the tertiary amino group-containing compound and the blocking agent is, for example, 50 mol% or more, preferably 60 mol% or more. Also, the amount of the blocking agent relative to the total amount (in moles) of the tertiary amino group-containing compound and the blocking agent is, for example, 95 mol% or less, preferably 90 mol% or less.

[0121] Furthermore, the proportion of the polyisocyanate compound (on a molar basis) per 100 moles of the total amount of the tertiary amino group-containing compound and the blocking agent is, for example, 5 moles or more, preferably 10 moles or more. Also, the proportion of the polyisocyanate compound (on a molar basis) per 100 moles of the total amount of the tertiary amino group-containing compound and the blocking agent is, for example, 100 moles or less, preferably 80 moles or less.

[0122] The reaction sequence between the polyisocyanate compound, the tertiary amino group-containing compound, and the blocking agent is not particularly limited. For example, first, the polyisocyanate compound and the tertiary amino group-containing compound are mixed, and a portion of the isocyanate groups of the polyisocyanate compound reacts with the tertiary amino group-containing compound. Then, these reaction products are mixed with the blocking agent, and the remainder of the isocyanate groups reacts with the blocking agent. This yields a tertiary amino group-containing blocked isocyanate.

[0123] Alternatively, for example, a polyisocyanate compound and a blocking agent are first mixed, and a portion of the isocyanate groups of the polyisocyanate compound reacts with the blocking agent. Then, these reaction products are mixed with a tertiary amino group-containing compound, and the remaining isocyanate groups of the polyisocyanate compound react with the tertiary amino group-containing compound. This yields a tertiary amino group-containing blocked isocyanate.

[0124] Alternatively, for example, a polyisocyanate compound, a tertiary amino group-containing compound, and a blocking agent are mixed, and a portion of the isocyanate groups of the polyisocyanate compound reacts with the tertiary amino group-containing compound, while the remainder of the isocyanate groups reacts with the blocking agent. This yields a tertiary amino group-containing blocked isocyanate.

[0125] Preferably, the polyisocyanate compound and the blocking agent are mixed to react a portion of the isocyanate groups of the polyisocyanate compound with the blocking agent. Then, these reaction products are mixed with a tertiary amino group-containing compound to react the remaining isocyanate groups of the polyisocyanate compound with the tertiary amino group-containing compound.

[0126] The equivalent ratio of the isocyanate group reactant in the blocking agent to the isocyanate group of the polyisocyanate compound (isocyanate group reactant / isocyanate group) is, for example, 0.1 or more, preferably exceeding 0.2, more preferably 0.3 or more, and even more preferably 0.75 or more. Furthermore, the equivalent ratio of the isocyanate group reactant in the blocking agent to the isocyanate group of the polyisocyanate compound (isocyanate group reactant / isocyanate group) is, for example, less than 0.99, preferably 0.98 or less, and more preferably 0.94 or less.

[0127] Furthermore, the reaction between the polyisocyanate compound and the blocking agent is carried out, for example, in an inert gas atmosphere. Examples of inert gases include nitrogen gas and argon gas.

[0128] The reaction temperature is, for example, 0°C or higher, preferably 20°C or higher. Alternatively, the reaction temperature is, for example, 80°C or lower, preferably 60°C or lower. The reaction pressure is, for example, atmospheric pressure. The reaction time is, for example, 0.5 hours or more, preferably 1.0 hour or more. Alternatively, the reaction time is, for example, 24 hours or less, preferably 12 hours or less.

[0129] As a result, some of the isocyanate groups in the polyisocyanate compound are blocked by the blocking agent, generating latent isocyanate groups (blocked isocyanate groups). Meanwhile, the remaining isocyanate groups in the polyisocyanate compound remain in a free state.

[0130] Next, the free isocyanate groups remaining in the blocked isocyanate (the remainder) are reacted with a tertiary amino group-containing compound.

[0131] The equivalent ratio of the isocyanate reactant group in the tertiary amino group-containing compound to the free isocyanate group (isocyanate reactant group / isocyanate group) is, for example, 0.1 or more, preferably 0.5 or more. Furthermore, the equivalent ratio of the isocyanate reactant group in the tertiary amino group-containing compound to the free isocyanate group (isocyanate reactant group / isocyanate group) is, for example, 1.3 or less, preferably 1.2 or less, and more preferably 1.1 or less.

[0132] Furthermore, the reaction between the blocked isocyanate and the tertiary amino group-containing compound is carried out, for example, in an inert gas atmosphere. Examples of inert gases include nitrogen gas and argon gas.

[0133] The reaction temperature is, for example, 0°C or higher, preferably 20°C or higher. Alternatively, the reaction temperature is, for example, 80°C or lower, preferably 60°C or lower. The reaction pressure is, for example, atmospheric pressure. The reaction time is, for example, 0.5 hours or more, preferably 1.0 hour or more. Alternatively, the reaction time is, for example, 24 hours or less, preferably 12 hours or less.

[0134] Furthermore, the completion of the reaction can be determined, for example, by using infrared spectroscopy to confirm the disappearance or decrease of the isocyanate group.

[0135] As a result, the isocyanate groups remaining in the free state in the blocked isocyanate react with the tertiary amino group-containing compound. This yields a tertiary amino group-containing blocked isocyanate.

[0136] Furthermore, each of the above reactions may be carried out without a solvent, for example, in the presence of an organic solvent.

[0137] Examples of organic solvents include ketones, nitriles, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, glycol ether esters, ethers, halogenated aliphatic hydrocarbons, and polar aprotons. Organic solvents can be used individually or in combination of two or more types.

[0138] A tertiary amino group-containing blocked isocyanate has both a latent isocyanate group, in which the isocyanate group is blocked by a blocking agent, and a tertiary amino group derived from a tertiary amino group-containing compound, within a single molecule.

[0139] The latent isocyanate groups, for example, make up 50 mol% or more, preferably 60 mol% or more, relative to the total amount (in moles) of latent isocyanate groups blocked by the blocking agent and tertiary amino groups. Alternatively, the latent isocyanate groups, for example, make up 95 mol% or less, preferably 90 mol% or less, relative to the total amount (in moles) of latent isocyanate groups blocked by the blocking agent and tertiary amino groups.

[0140] The amount of tertiary amino groups is, for example, 5 mol% or more, preferably 10 mol% or more, relative to the total amount (moles) of latent isocyanate groups whose isocyanate groups are blocked by the blocking agent and tertiary amino groups. Furthermore, the amount of tertiary amino groups is, for example, 50 mol% or less, preferably 40 mol% or less, relative to the total amount (moles) of latent isocyanate groups whose isocyanate groups are blocked by the blocking agent and tertiary amino groups.

[0141] Furthermore, the tertiary amino group equivalent of the tertiary amino group-containing block isocyanate is, for example, 300 or more, preferably 1000 or more, more preferably 1500 or more, and even more preferably 3000 or more. Also, the tertiary amino group equivalent of the tertiary amino group-containing block isocyanate is, for example, 10000 or less, preferably 8000 or less, more preferably 6000 or less, and even more preferably 4000 or less. Note that the tertiary amino group equivalent of the tertiary amino group-containing block isocyanate is the molecular weight of the tertiary amino group-containing block isocyanate per mole of amino groups (molecular weight of the tertiary amino group-containing block isocyanate / number of amino group functional groups in one molecule of the tertiary amino group-containing block isocyanate), and is calculated from the charging ratio.

[0142] Next, in this method, a tertiary amino group-containing block isocyanate is reacted with an acid. As a result, at least some of the tertiary amino groups in the tertiary amino group-containing block isocyanate react with the acid to form a tertiary ammonium salt (secondary reaction step).

[0143] The reaction between a tertiary amino group-containing block isocyanate and an acid is, for example, a neutralization reaction. To react a tertiary amino group-containing block isocyanate with an acid, the acid is added to the tertiary amino group-containing block isocyanate.

[0144] The equivalent ratio of acid to tertiary amino groups in the tertiary amino group-containing block isocyanate (acid / tertiary amino group) is, for example, 0.1 or more, preferably 0.5 or more, more preferably 0.8 or more, even more preferably 0.9 or more, and particularly preferably 1.1 or more. Alternatively, the equivalent ratio of acid to tertiary amino groups in the tertiary amino group-containing block isocyanate (acid / tertiary amino group) is, for example, 5.0 or less, preferably 3.0 or less, and more preferably 2.0 or less. In other words, it is preferable that the acid is in excess of the tertiary amino groups.

[0145] Furthermore, the reaction between the tertiary amino group-containing block isocyanate and the acid is not particularly limited, but is carried out, for example, under air or in an inert gas atmosphere. Examples of inert gases include nitrogen gas and argon gas.

[0146] The reaction temperature is, for example, 0°C or higher, preferably 20°C or higher. Alternatively, the reaction temperature may be, for example, 80°C or lower, preferably 60°C or lower. The reaction pressure is not particularly limited, but examples include pressurized conditions and atmospheric pressure conditions, with atmospheric pressure conditions being preferred. The reaction time is, for example, 0.1 hours or more, preferably 0.5 hours or more. Alternatively, the reaction time may be, for example, 24 hours or less, preferably 12 hours or less.

[0147] Furthermore, the above reaction is preferably carried out in the presence of the organic solvent described above.

[0148] As a result, the tertiary amino group in the tertiary amino group-containing block isocyanate is neutralized by the acid, forming a tertiary ammonium salt as a cationic group.

[0149] This process produces a tertiary ammonium salt-containing blocked isocyanate as a reaction product of a polyisocyanate compound, a tertiary amino group-containing compound, a blocking agent, and an acid.

[0150] In the tertiary ammonium salt-containing block isocyanate, the content of the tertiary ammonium salt is, for example, more than 1.5% by mass of the total amount of the tertiary ammonium salt-containing block isocyanate (secondary reaction product), preferably 1.9% by mass or more, more preferably 2.0% by mass or more, even more preferably 5.0% by mass or more, even more preferably 10.0% by mass or more, even more preferably 20.0% by mass or more, and particularly preferably 30.0% by mass or more. Furthermore, the content of the tertiary ammonium salt is, for example, 70.0% by mass or less of the total amount of the tertiary ammonium salt-containing block isocyanate (secondary reaction product), preferably 60.0% by mass or less, more preferably 50.0% by mass or less, and even more preferably 40.0% by mass or less.

[0151] The proportion of tertiary ammonium salts is calculated based on the ratio of polyisocyanate compounds, tertiary amino group-containing compounds, blocking agents, and acid.

[0152] Furthermore, the cation equivalent of a tertiary ammonium salt-containing block isocyanate is, for example, the same as that of a tertiary amino group in a tertiary amino group-containing block isocyanate. That is, the cation equivalent of the antibacterial agent is, for example, 300 or more, preferably 1000 or more, more preferably 1500 or more, and even more preferably 3000 or more. Also, the cation equivalent of a tertiary ammonium salt-containing block isocyanate is, for example, 10000 or less, preferably 8000 or less, more preferably 6000 or less, and even more preferably 4000 or less. Note that the cation equivalent of a tertiary ammonium salt-containing block isocyanate is calculated from the charging ratio, which is the molecular weight of the tertiary ammonium salt-containing block isocyanate per mole of cation (tertiary ammonium salt) (molecular weight of tertiary ammonium salt-containing block isocyanate / number of moles of cation in one molecule of antibacterial agent).

[0153] In a tertiary ammonium salt-containing blocked isocyanate, the average number of functional groups of the latent isocyanate groups whose isocyanate groups are blocked by the blocking agent is, for example, 1 or more, preferably 1.5 or more. Furthermore, in a tertiary ammonium salt-containing blocked isocyanate, the average number of functional groups of the latent isocyanate groups whose isocyanate groups are blocked by the blocking agent is, for example, 3 or less, preferably 2.5 or less.

[0154] Furthermore, when an organic solvent is used in the reaction between a tertiary amino group-containing block isocyanate and an acid, the tertiary ammonium salt-containing block isocyanate is dissolved in the reaction solution containing the organic solvent. In this case, water is added to the reaction solution containing the tertiary ammonium salt-containing block isocyanate, and the reaction solution and water are emulsified using a stirrer. Then, the organic solvent is removed by volatilization, for example, by heating the emulsified solution under reduced pressure. This produces an aqueous dispersion of the antibacterial agent.

[0155] The solid content concentration of the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 1% by mass or more, preferably 10% by mass or more. Alternatively, the solid content concentration of the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 80% by mass or less, preferably 50% by mass or less.

[0156] The viscosity (at 25°C) of the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 1 mPa·s or more, preferably 3 mPa·s or more. Alternatively, the viscosity (at 25°C) of the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 800 mPa·s or less, preferably 500 mPa·s or less.

[0157] The pH of the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 3.0 or higher, preferably 4.0 or higher. Alternatively, the pH of the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 9.0 or lower, preferably 8.0 or lower.

[0158] The particle size in the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 5 nm or larger, preferably 10 nm or larger. Alternatively, the particle size in the aqueous dispersion of tertiary ammonium salt-containing block isocyanate is, for example, 500 nm or smaller, preferably 300 nm or smaller.

[0159] The antibacterial agent only needs to contain the tertiary ammonium salt-containing blocked isocyanate mentioned above. For example, the antibacterial agent consists of an aqueous dispersion of the tertiary ammonium salt-containing blocked isocyanate.

[0160] Furthermore, the antibacterial agent may also contain the above-mentioned polyisocyanate compound. That is, the antibacterial agent may contain the above-mentioned tertiary ammonium salt-containing block isocyanate and the above-mentioned polyisocyanate compound. In addition, the antibacterial agent may also contain the above-mentioned polyisocyanate compound modified with the above-mentioned hydrophilic compound. That is, the antibacterial agent may contain the above-mentioned tertiary ammonium salt-containing block isocyanate and the above-mentioned polyisocyanate compound modified with the above-mentioned hydrophilic compound. The content ratio of the polyisocyanate compound and / or the above-mentioned polyisocyanate compound modified with the hydrophilic compound is not particularly limited and can be set as appropriate depending on the purpose and application.

[0161] This allows for adjustment of the isocyanate group content (including free and latent isocyanate groups) in the antibacterial agent, thereby adjusting the reactivity of the antibacterial agent to the main ingredient described later.

[0162] More specifically, the average number of functional groups of the isocyanate groups (including free and latent isocyanate groups) of the antibacterial agent is, for example, 2 or more, preferably 2.5 or more. Also, the average number of functional groups of the isocyanate groups (including free and latent isocyanate groups) of the antibacterial agent is, for example, 4 or less, preferably 3.5 or less.

[0163] In addition, the above-mentioned antibacterial agents may contain additives. Examples of additives include solvents, catalysts, epoxy resins, coating properties improvers, leveling agents, defoamers, antioxidants, UV absorbers, thickeners, anti-settling agents, plasticizers, surfactants, pigments, fillers, organic microparticles, inorganic microparticles, and antifungal agents. The amount of additives used is determined appropriately depending on the purpose and application.

[0164] Furthermore, the above-mentioned antibacterial agents may be used in combination with known antibacterial agents. That is, the above-mentioned antibacterial agents can be mixed with other antibacterial agents. The mixing ratio should be determined appropriately depending on the purpose and application.

[0165] <Effects and Effects> The above antibacterial agent comprises a primary reaction product of a polyisocyanate compound having multiple isocyanate groups, a tertiary amino group-containing compound that reacts with some of the multiple isocyanate groups, and a blocking agent that blocks the remainder of some of the multiple isocyanate groups, and a secondary reaction product of an acid that reacts with at least some of the tertiary amino groups of the tertiary amino group-containing compound to form a tertiary ammonium salt, wherein the ratio of the tertiary amino group-containing compound to the total amount of the polyisocyanate compound, the tertiary amino group-containing compound, and the blocking agent exceeds a predetermined value.

[0166] In other words, the above antibacterial agent contains a tertiary ammonium salt in a predetermined proportion. Therefore, the antibacterial agent of the present invention has excellent antibacterial properties. In particular, in the above antibacterial agent, the tertiary amino group-containing compound reacts with the polyisocyanate compound. The tertiary amino group-containing compound then forms a tertiary ammonium salt.

[0167] As a result, the above antibacterial agent exhibits superior antibacterial properties compared to cases where a tertiary amino group-containing compound forms a tertiary ammonium salt on its own without reacting with a polyisocyanate compound.

[0168] Furthermore, the above-mentioned antibacterial agent contains not only a tertiary ammonium salt but also isocyanate groups blocked by a blocking agent. Therefore, by deblocking the blocking agent, the isocyanate groups can be subjected to chemical reactions and easily react with various resins (immobilized materials). As a result, the above-mentioned antibacterial agent allows for the selection of immobilized materials with a relatively high degree of freedom, enabling the immobilization of antibacterial tertiary ammonium salts in resins.

[0169] Furthermore, because the above antibacterial agent contains tertiary ammonium salts in a predetermined or higher proportion, it exhibits excellent water dispersibility.

[0170] <Resin> The following describes in detail a method for immobilizing an antibacterial agent on a resin (the material to be immobilized). When immobilizing an antibacterial agent on a resin, the antibacterial agent is preferably also used as a curing agent.

[0171] The average number of functional groups in the curing agent's isocyanate groups (including free and latent isocyanate groups) is, for example, 2 or more, preferably 2.5 or more. Alternatively, the average number of functional groups in the curing agent's isocyanate groups (including free and latent isocyanate groups) is, for example, 4 or less, preferably 3.5 or less.

[0172] More specifically, in this method, a resin composition is obtained by mixing a main component that can react with free isocyanate groups with an antibacterial agent as a curing agent. Next, the resin composition is heated to deblock the latent isocyanate groups of the antibacterial agent without dissociating at least a portion of the tertiary ammonium salt, thereby obtaining free isocyanate groups. Then, the free isocyanate groups are reacted with the main component. This makes it possible to obtain a resin in which the antibacterial agent is immobilized in the molecule. Examples of resins include polyurethane resins, polyester resins, and acrylic resins, with polyurethane resins being preferred.

[0173] <Main ingredient> The main component is a component that reacts with free isocyanate groups obtained by deblocking latent isocyanate groups to form a resin. For example, when the resin is a polyurethane resin, the main component may be an active hydrogen group-containing compound. An active hydrogen group-containing compound is a compound that contains one or more active hydrogen groups in its molecule. Examples of active hydrogen group-containing compounds include polyol compounds and polyamine compounds. Preferably, a polyol compound is used as the active hydrogen group-containing compound.

[0174] Examples of polyol compounds include low molecular weight polyols and high molecular weight polyols.

[0175] The number-average molecular weight of low molecular weight polyols is, for example, less than 300, preferably less than 400. Low molecular weight polyols have two or more hydroxyl groups.

[0176] Examples of low molecular weight polyols include dihydric alcohols, trihydric alcohols, tetrahydric alcohols, pentahydric alcohols, hexahydric alcohols, heptahydric alcohols, and octahydric alcohols. Examples of dihydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2,2-trimethylpentanediol, 3,3-dimethylolheptane, alkane (C7~20)diol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, hydrogenated bisphenol A, 1,4-dihydroxy-2-butene, 2,6-dimethyl-1-octen-3,8-diol, bisphenol A, diethylene glycol, triethylene glycol, and dipropylene glycol. Examples of trihydric alcohols include glycerin, trimethylolpropane, and triisopropanolamine. Examples of tetrahydric alcohols include tetramethylolmethane (pentaerythritol) and diglycerin. Examples of pentahydric alcohols include xylitol. Examples of hexahydric alcohols include sorbitol, mannitol, allitol, isitol, dalucitol, althritol, inositol, and dipentaerythritol. Examples of heptahydric alcohols include perseitol. Examples of octahydric alcohols include sucrose. Low molecular weight polyols can be used alone or in combination of two or more.

[0177] The number-average molecular weight of high molecular weight polyols is, for example, 300 or more, preferably 400 or more, and more preferably 500 or more. High molecular weight polyols have two or more hydroxyl groups.

[0178] Examples of high molecular weight polyols include polyether polyols, polyester polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, acrylic polyols, vinyl monomer-modified polyols, and fluorine-containing polyols.

[0179] Examples of polyether polyols include polyoxyalkylene (C2-C3) polyols and polytetramethylene ether polyols.

[0180] Examples of polyester polyols include adipic acid-based polyester polyols, phthalic acid-based polyester polyols, and lactone-based polyester polyols.

[0181] Examples of polycarbonate polyols include ring-opening polymers of ethylene carbonate using the low molecular weight polyols mentioned above as initiators, and amorphous polycarbonate polyols obtained by copolymerizing the dihydric alcohols mentioned above with the ring-opening polymers.

[0182] Examples of polyurethane polyols include polyester polyurethane polyol, polyether polyurethane polyol, polycarbonate polyurethane polyol, and polyester polyether polyurethane polyol.

[0183] Examples of epoxy polyols include epoxy polyols obtained by the reaction of the low molecular weight polyols mentioned above with polyfunctional halohydrins.

[0184] Examples of vegetable oil polyols include castor oil, coconut oil, and ester-modified castor oil polyols.

[0185] Examples of polyolefin polyols include polybutadiene polyols and partially saponifiable ethylene-vinyl acetate copolymers.

[0186] Examples of acrylic polyols include copolymers of hydroxyl group-containing acrylates and copolymerizable vinyl monomers that can copolymerize with hydroxyl group-containing acrylates.

[0187] Vinyl monomer-modified polyols are obtained by the reaction of the above-mentioned high molecular weight polyol with a vinyl monomer.

[0188] Examples of fluorine-containing polyols include acrylic polyols in which a fluorine compound is incorporated as a copolymerizable vinyl monomer in the copolymerization of the acrylic polyols described above.

[0189] High molecular weight polyols can be used alone or in combination of two or more types.

[0190] Polyol compounds can be used alone or in combination of two or more types.

[0191] Among polyol compounds, high molecular weight polyols are preferred, and more preferably, polyurethane polyols and acrylic polyols are preferred.

[0192] The main component may contain additives. Examples of additives include reaction solvents, catalysts, epoxy resins, coating properties improvers, leveling agents, defoamers, antioxidants, UV absorbers, thickeners, anti-settling agents, plasticizers, surfactants, pigments, fillers, organic microparticles, inorganic microparticles, and antifungal agents. The amount of additives used is determined appropriately depending on the purpose and application.

[0193] <Resin composition> In the production of the resin composition, the main component described above is blended with an antibacterial agent as a curing agent. The blending ratio is set appropriately according to the purpose and application. For example, the equivalent ratio of latent isocyanate groups of the antibacterial agent to the active hydrogen groups of the main component (active hydrogen group-containing compound) (latent isocyanate group / active hydrogen group) is, for example, 0.1 or more, preferably 0.5 or more. Also, the equivalent ratio of latent isocyanate groups of the antibacterial agent to the active hydrogen groups of the main component (active hydrogen group-containing compound) (latent isocyanate group / active hydrogen group) is, for example, 5 or less, preferably 3 or less.

[0194] The resin composition is then applied to the object by a known coating method and dried to form a coating film. Subsequently, the coating film is heated and, if necessary, aged.

[0195] The heating temperature and heating time are set so that the blocking agent can be dissociated from the latent isocyanate group, and at least a portion of the tertiary ammonium group remains without dissociating from the latent isocyanate.

[0196] The heating temperature is, for example, 50°C or higher, preferably 80°C or higher. Alternatively, the heating temperature may be, for example, 180°C or lower, preferably 150°C or lower, more preferably 130°C or lower, even more preferably 120°C or lower, and particularly preferably 110°C or lower.

[0197] The heating time is, for example, 10 seconds or more, preferably 30 seconds or more. Alternatively, the heating time is, for example, 10 minutes or less, preferably 5 minutes or less.

[0198] This deblocks the latent isocyanate group of the antibacterial agent. On the other hand, at least a portion of the tertiary ammonium group remains without dissociating from the latent isocyanate.

[0199] Then, the free isocyanate groups of the antibacterial agent react with the main agent, yielding a cured resin. As a result, at least some of the tertiary ammonium groups are immobilized on the resin. Consequently, a resin (cured product) with excellent antibacterial properties is obtained.

[0200] Furthermore, if the antibacterial agent is formulated in excess, the excess antibacterial agent will be incorporated into the resin (cured product) without reacting with the main agent. As a result, particularly superior antibacterial properties can be obtained due to the excess antibacterial agent.

[0201] Examples of applications for such resin compositions (uncured) and resins (cured) include fiber treatment agents, water repellents, paint compositions, adhesives, antistatic agents, papermaking treatment agents, wet paper strength enhancers, receiving layers for recording media, electrodeposition coating compositions, antibacterial and antiviral compositions, encapsulated compositions, optical components, and latex compositions. Among the applications of resin compositions (uncured) and resins (cured), preferred applications include fiber treatment agents, water repellents, paint compositions, and adhesives, with fiber treatment agents and water repellents being more preferred. [Examples]

[0202] The present invention will be further described with reference to the following examples, but the present invention is not limited thereto. Specific numerical values ​​such as blending ratios (content), physical properties, and parameters used in the following description may be replaced with the corresponding upper limits (numerical values ​​defined as "less than or equal to" or "less than") or lower limits (numerical values ​​defined as "greater than or equal to" or "greater than or equal to" or "greater than or equal to") of the blending ratios (content), physical properties, and parameters described in the "Modes for Carrying Out the Invention" above. Note that "parts" and "%" refer to mass unless otherwise specified.

[0203] <Preparation of antibacterial agents> Examples 1-2 At room temperature (25°C), 200 parts by mass of an isocyanurate derivative of hexamethine diisocyanate (HDI) (polyisocyanate compound, trade name: Takenate D170N, solid content 100% by mass, isocyanate group content 20.7%, manufactured by Mitsui Chemicals, Inc.) and ethyl acetate (solvent) were charged into a 2 L reactor equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube.

[0204] Next, 3,5-dimethylpyrazole (DMP, dissociation temperature 120°C, blocking agent) was added to the reactor. The amount of DMP added was as shown in Table 1, relative to 100 moles of isocyanate groups in the isocyanurate derivative of HDI. The isocyanurate derivative of HDI and DMP were then reacted.

[0205] Next, 1,1,3,3-tetramethylguanidine (TMG, dissociation temperature 150°C, tertiary amino group-containing compound) was added to the reactor. The addition ratio of TMG was as shown in Table 1, relative to 100 moles of isocyanate groups in the isocyanurate derivative of HDI. The isocyanurate derivative of HDI and TMG were then reacted.

[0206] Subsequently, FT-IR spectroscopy confirmed that the isocyanate group was blocked. This yielded a reaction solution containing a tertiary amino group-containing blocked isocyanate.

[0207] Next, acetic acid was added to the reaction mixture and stirred. The ratio of acetic acid added was 2 moles per 1 mole of tertiary amino group-containing compound (TMG). At this time, the temperature of the reaction mixture was 28°C. The stirring time was 0.5 hours.

[0208] As a result, the tertiary amino group derived from the tertiary amino group-containing compound was neutralized by acetic acid, forming ammonium acetate as a tertiary ammonium salt. This yielded a reaction solution containing an antibacterial agent.

[0209] Subsequently, 220 parts by mass of water were added to 120 parts by mass of the reaction solution containing the antibacterial agent. The reaction solution and water were then emulsified by stirring with a homomixer. Next, under reduced pressure, ethyl acetate (solvent) was removed from the emulsion, and a portion of the water was also removed by distillation. A water dispersion of the antibacterial agent was prepared in this manner. The solid content concentration of the water dispersion of the antibacterial agent was 30% by mass.

[0210] Example 3 N-dimethylaminoethanol (DMAE, desorption temperature 150°C or higher, tertiary amino group-containing compound) was used instead of 1,1,3,3-tetramethylguanidine (TMG, dissociation temperature exceeding 150°C, tertiary amino group-containing compound). Otherwise, an aqueous dispersion of the antibacterial agent was prepared by the same method as in Example 1. The solid content concentration of the aqueous dispersion of the antibacterial agent was 30% by mass.

[0211] Comparative Example 1 1,1,3,3-tetramethylguanidine (TMG, a tertiary amino group-containing compound) was prepared as an antimicrobial agent.

[0212] Subsequently, water was added to the antibacterial agent to prepare an aqueous solution of the antibacterial agent. The solid content concentration of the aqueous solution of the antibacterial agent was 30% by mass.

[0213] Comparative Example 2 In a reactor, 1,1,3,3-tetramethylguanidine (TMG, a tertiary amino group-containing compound) was mixed with acetic acid and stirred. The ratio of acetic acid added was 2 moles per 1 mole of the tertiary amino group-containing compound (TMG). At this time, the temperature of the reaction mixture was 28°C. The stirring time was 0.5 hours.

[0214] As a result, 1,1,3,3-tetramethylguanidine was neutralized by acetic acid to form ammonium acetate, a tertiary ammonium salt. This yielded a reaction solution containing an antibacterial agent.

[0215] Subsequently, water was added to the antibacterial agent to prepare an aqueous solution of the antibacterial agent. The solid content concentration of the aqueous solution of the antibacterial agent was 30% by mass.

[0216] Comparative Examples 3-5 An aqueous dispersion of the antibacterial agent was prepared using the same method as in Example 1, except that the formulation was changed as shown in Table 1.

[0217] In Comparative Example 5, poly(oxyethylene)methyl ether (methoxy polyethylene glycol, methoxyPEG1000, MeO-PEG) was used instead of 1,1,3,3-tetramethylguanidine (TMG, a tertiary amino group-containing compound).

[0218] Comparative Examples 6-8 The aqueous dispersion of the antibacterial agent from Example 2 and the aqueous dispersion of the antibacterial agent from Comparative Example 5 were mixed in the proportions shown in Table 1. This prepared an aqueous dispersion of the antibacterial agent.

[0219] <Rating> <1.Water dispersibility> In each example and comparative example, the dispersibility of the antibacterial agent (reaction solution containing the antibacterial agent) in water was evaluated based on the following criteria. ○: The antibacterial agent disperses quickly in water. △: The antibacterial agent disperses in the water after prolonged stirring (0.5 hours or more). ×: The antibacterial agent does not disperse in water. Precipitation occurs. <2: Minimum Inhibitory Concentration (MIC) Test>

[0220] (1) Preculture (Test bacterial species) I. Escherichia coli (E. coli, NBRC-3972, Distributed by the National Institute of Technology and Evaluation, Escherichia coli) II. Staphylococcus aureus (S. aureus, NBRC-12732, Distributed by the National Institute of Technology and Evaluation, Staphylococcus aureus)

[0221] The bacteria described in I and II above were tested species cultured at 35±1°C for 20±4 hours using liquid medium (LB medium, BD Difco (trade name) LB Broth Mirror, Becton Dickinson) that had been autoclaved at 121°C for 20 minutes.

[0222] (2) Bacterial liquid preparation The bacterial species cultured in (1) above were suspended in LB medium sterilized by autoclaving at 121°C for 20 minutes, and the Optical Density (OD) of the bacterial suspension was measured and adjusted to less than 2.0.

[0223] (3) Sample preparation A dimethyl sulfoxide solution containing 3% antibacterial agent (sample) was prepared, and the sample was added to LB medium sterilized by autoclaving at 121°C for 20 minutes to obtain a mixture. A maximum concentration of 1000 ppm of antibacterial agent was used, and eight 2x dilution series were prepared.

[0224] (4) MIC measurement test The bacterial suspension prepared in (2) was inoculated into each dilution series in (3), and incubated at 35°C for 24 ± 2 hours. After that, bacterial growth was visually confirmed, and the maximum dilution concentration at which no growth occurred was defined as the MIC value.

[0225] <3: Antimicrobial film test> (Test bacterial species) Escherichia coli (E. coli, NBRC-3972, Distributed by the National Institute of Technology and Evaluation, Escherichia coli)

[0226] Based on the "Antibacterial processed products - Antibacterial test methods and antibacterial effects" established in JIS Z 2801:2010, the antibacterial activity against Staphylococcus aureus was evaluated as follows.

[0227] (1) A mixture was prepared by mixing 1.8 parts by mass (based on solid content) of an antibacterial agent, 88.2 parts by mass (based on solid content) of the main component listed in Table 2, and 10.0 parts by mass of isopropyl alcohol. Water was then added to the mixture to adjust its solid content concentration to 10% by mass. Next, the mixture was coated onto a polyethylene terephthalate film (product name Lumirror S10, manufactured by Toray Industries, Inc.) using a bar coater and cured by heating under the curing conditions (temperature / time) listed in Table 2. This resulted in a film with a thickness of 0.1 to 2.0 μm.

[0228] Furthermore, as controls 1 and 2, 90 parts by mass (based on solid content) of the main component listed in Table 2 and 10.0 parts by mass of isopropyl alcohol were mixed to obtain a mixture. Water was then added to the mixture to adjust the solid content concentration to 10% by mass. Next, the above mixture was coated onto polyethylene terephthalate film (product name Lumirror S10, manufactured by Toray Industries, Inc.) using a bar coater and cured by heating under the curing conditions (temperature / time) listed in Table 2. This resulted in films with a thickness of 0.1 to 2.0 μm.

[0229] (2) The film was cut into 50±2mm squares to form test specimens. The test specimens were placed in a sterile plastic petri dish, and the test bacterial solution (bacterial count 2.5 × 10⁶) was added. 5 ~10×10 5 A 0.4 mL sample of the test bacterial culture ((1 cell / mL)) was inoculated. The test bacterial suspension was prepared using the following method.

[0230] Specifically, the cultured bacteria were pre-cultured in an incubator at a temperature of 35±1℃ for 20±4 hours using LB medium (BD Difco (trade name) LB Broth Mirror, Becton Dickinson) (Solution 1).

[0231] Next, the first solution was inoculated onto slant medium (ordinary agar medium, Nutrient agar, Merck) and pre-cultured in an incubator at a temperature of 35±1°C for 20±4 hours (second solution).

[0232] Subsequently, the second solution was adjusted to an appropriate concentration using a separately prepared 1 / 500 nutrient broth medium (Merck) (third solution).

[0233] (3) On the other hand, a 50±2 mm square polyethylene terephthalate film (product name Lumirror S10, manufactured by Toray Industries, Inc.) was prepared as a control sample, and the test bacterial solution was inoculated into it in the same way as the test specimen.

[0234] (4) Next, a 40±2 mm square biaxially oriented polypropylene (OPP) film was placed over the inoculated test bacterial solution, thereby ensuring even inoculation of the entire film. The film was then incubated at a temperature of 35±1°C and a relative humidity of 85±5% for 20±4 hours.

[0235] (5) Immediately after inoculation of the test bacterial suspension, or after culturing as described in (4) above, 10 mL of SCDLP medium (SCDLP Medium Daigo (trade name), manufactured by Nippon Pharmaceutical Co., Ltd.) was added, and the test bacterial suspension on the test piece was washed at least four times to completely recover the bacterial suspension. The recovered liquid (wash solution) was then promptly subjected to the next step, and the number of viable cells was measured.

[0236] (6) A 10-fold dilution series was prepared using the liquid (washout solution) recovered in (5) above and phosphate-buffered saline.

[0237] Subsequently, each dilution series was mixed with standard agar medium (Standard Agar Medium Daigo (trade name), product of Nippon Pharmaceutical Co., Ltd.) to prepare culture media. The culture media were then incubated at 35±1℃ for 20±4 hours, and the number of colonies was measured. Petri dishes from dilution series showing 30 to 300 colonies were used for counting.

[0238] (7) Based on the measurement results, the number of viable bacteria was calculated using the following formula. N = C × D × V / A N: Number of viable bacteria (test piece 1cm) 2 (Around) C: Number of villages D: Dilution ratio (the dilution ratio of each diluent in the petri dish used) V: Volume of SCDLP medium used for washing (mL) A: Surface area of ​​the coating film (cm²) 2 )

[0239] (8) The antibacterial activity value was calculated using the following formula, and if R was 2.0 or higher, it was considered to have antibacterial activity (○). If R was less than 2.0, it was considered to have no antibacterial activity (×). R = (Ut - U0) - (At - U0) = Ut - At R: Antimicrobial activity value U0: The average logarithmic value of the number of viable bacteria immediately after inoculation of the unprocessed test specimen. Ut: Mean logarithmic value of the number of viable bacteria in untreated test specimens after 24 hours. At: The average logarithmic value of the number of viable bacteria in antimicrobially treated test pieces after 24 hours.

[0240] [Table 1]

[0241] [Table 2] The details of the abbreviations used in each table are as follows.

[0242] Takenate D170N: Product name, isocyanurate derivative of hexamethine diisocyanate, isocyanate group content 20.7%, manufactured by Mitsui Chemicals, Inc. TMG: 1,1,3,3-tetramethylguanidine, dissociation temperature 150℃ DMAE: N-dimethylaminoethanol, dissociation temperature exceeding 150°C DMP: 3,5-dimethylpyrazole, dissociation temperature 120°C MeO-PEG: MethoxyPEG #1000, number average molecular weight 1000, manufactured by Toho Chemical Industry Co., Ltd. W6355: Main component, product name Takelac W-6355, water-based polyurethane resin, nonionic, manufactured by Mitsui Chemicals, Inc. W6110: Main component, product name Takelac W-6110, water-based polyurethane resin, anionic, manufactured by Mitsui Chemicals, Inc.

Claims

1. Polyisocyanate compounds having multiple isocyanate groups, A tertiary amino group-containing compound that reacts with some of the multiple isocyanate groups, and A primary reaction product of a blocking agent that blocks the remainder of a portion of the multiple isocyanate groups, At least a portion of the tertiary amino group of the tertiary amino group-containing compound and an acid that forms a tertiary ammonium salt It contains the secondary reaction product of, The polyisocyanate compound is an isocyanurate modified form of hexamethylene diisocyanate, The tertiary amino group-containing compound is at least one selected from the group consisting of 1,1,3,3-tetramethylguanidine, N-dimethylaminoethanol, N-methylpiperazine, N-methylhomopiperazine, and N,N,N'-trimethylethylenediamine. The blocking agent is at least one selected from the group consisting of 3-methyl-5-phenylpyrazole, 3,5-diphenylpyrazole, 4-benzyl-3,5-dimethylpyrazole, 4-nitro-3,5-dimethylpyrazole, 4-bromo-3,5-dimethylpyrazole, 3,5-dimethylpyrazole, 3,5-diisopropylpyrazole, and 3,5-di-t-butylpyrazole. The dissociation temperature of the blocking agent is 50°C or higher and 150°C or lower. An antibacterial agent wherein the proportion of the tertiary amino group-containing compound to the total amount of the polyisocyanate compound, the tertiary amino group-containing compound, and the blocking agent exceeds 1.5% by mass.

2. The antibacterial agent according to claim 1, wherein the acid includes an organic acid.

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