JPH11222402A - Antimicrobial polymer particle and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antimicrobial polymer particle having improved affinity for resins and coating film properties and excellent antimicrobial properties by using an antimicrobial metal component. SOLUTION: This antimicrobial polymer particle is obtained by supporting an antimicrobial metal component capable of forming coordinate bond to a functional group (silver component or the like) on a hydrophilic polymer particle (0.1 nm to 100 μm average particle diameter) consisting of hydrophilic polymer gel having a crosslinked structure comprising hydrophilic units each containing a nitrogen atom, units each having a functional group containing at least one atom selected from oxygen nitrogen and sulfur and crosslinked units. Wherein, the functional group includes a carboxyl group, an amino group, an imino group, a mercapto group or the like. The supported amount of the antimicrobial metal component is about 0.01-70 wt.% in terms of the metal based on the total amount. The antimicrobial particle has good affinity for resins and is useful as an antimicrobial resin composition (a coating resin composition or the like).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial polymer particle which effectively exhibits antibacterial properties against various microorganisms (bacteria, molds, etc.), a method for producing the same, and a coating agent containing the antibacterial polymer particle. The present invention relates to an antibacterial resin composition useful as such.

[0002]

2. Description of the Related Art In recent years, antibacterial treatment has been studied for various products. This antibacterial treatment is usually carried out by kneading an organic or inorganic antibacterial agent into a plastic or coating a paint containing an antibacterial agent. Among the above antibacterial agents, organic antibacterial agents are excellent in antibacterial properties, immediate action, and dispersibility in resins. However, elution from the substrate,
In addition to heat resistance and safety to the human body, there are problems such as bacteria expressing drug resistance. On the other hand, an inorganic antibacterial agent in which a metal ion having antibacterial activity (silver, zinc, copper, etc.) is supported on an inorganic carrier (particulate inorganic carrier such as zeolite, silica gel, etc.) has various advantages such as heat resistance. It has excellent properties, broad antibacterial spectrum, difficulty in acquiring drug resistance, and safety to the human body. Since the antibacterial activity of the antibacterial agent is expressed on the surface of the product after the antibacterial treatment, it is effective to coat the surface of the product with the antibacterial agent in order to use the antibacterial agent efficiently.

However, when an inorganic antibacterial agent is applied to a coating on the surface of a substrate, various problems occur. For example, since an inorganic antibacterial agent basically uses a hydrophilic zeolite, silica gel or the like as a carrier, if it is mixed with a coating agent, it is difficult to i) disperse the antibacterial agent uniformly in the coating agent; ii) Since the carrier particle size and specific gravity are relatively large, they settle in the coating agent and are easily separated, and it is necessary to mix a large amount of antibacterial agent in order to increase the frequency of contact with bacteria and express a sufficient antibacterial effect . And iii)
Due to poor affinity and adhesion to the organic binder, the antibacterial agent easily falls off the surface of the coating film, the mechanical strength of the coating film decreases, and iv) the transparency of the coating film is impaired. Further, depending on the type of the inorganic antibacterial agent, it may be colored by irradiation with light such as ultraviolet rays.

[0004] On the other hand, antibacterial agents having silver ions held in an organic polymer have also been proposed. JP-A-2-288804 discloses a deodorant antibacterial composition containing an aqueous solution or dispersion of a carboxyl group-containing polymer and silver ions.
Japanese Patent Application Laid-Open No. 4-173712 discloses an antibacterial agent having sulfonic acid groups carrying silver ions on the surface of acrylic polymer particles. JP-A-8-151310 discloses an antibacterial polymer composed of a combination of a maleic acid polymer and silver ions, and JP-A-8-165212 discloses a (meth) acrylate- (meth) acrylic acid An antimicrobial agent composed of silver polymer particles is disclosed.
However, in these antibacterial agents, silver ions are eluted at an early stage, and high antibacterial properties cannot be maintained for a long period of time. In particular, recently, in a high-humidity environment or a water-around environment in which microorganisms are liable to grow, the antibacterial activity cannot be effectively exhibited, and the sustainability is not sufficient.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an antibacterial polymer particle capable of effectively exhibiting a high antibacterial activity over a long period of time despite the use of an inorganic antibacterial metal component, and its antibacterial property. An object of the present invention is to provide an antibacterial resin composition containing conductive polymer particles and a method for producing the same. Another object of the present invention is to provide an antibacterial polymer particle capable of effectively exhibiting antibacterial properties with an increase in humidity or moisture, having environmental responsiveness, an antibacterial resin composition containing the antibacterial polymer particle, and It is to provide a manufacturing method of. Still another object of the present invention is to provide an antibacterial polymer particle having excellent dispersibility, affinity with an organic polymer, and film properties even when used as a resin composition such as a coating agent, and an antibacterial resin composition containing the same. As well as a method for producing them.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and found that an antibacterial metal component is supported on an organic polymer carrier having a hydrophilic unit.
Able to release antimicrobial metal components in response to humidity environment, maintain high antimicrobial activity over a long period of time, and obtain an antimicrobial resin composition having high affinity with organic polymers and useful as antimicrobial coating agent etc. And completed the present invention. That is, the antibacterial polymer particles of the present invention, an antibacterial metal component composed of a metal ion or a metal compound,
It is supported by being chemically bonded to the polymer particles. In this antimicrobial polymer particle, the antimicrobial metal component is generally chemically bonded to the polymer particle via a functional group containing at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, and a sulfur atom. doing. That is,
The polymer particles constituting the antibacterial polymer include a hydrophilic unit and at least one atom selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and have a functional group capable of chemically bonding to the antibacterial metal component. And a hydrophilic polymer having a cross-linked structure including a cross-linked unit. The average particle size of the polymer particles is
It may be about 0.1 nm to 100 μm. As the antibacterial metal component, silver, platinum, copper, zinc, nickel,
Examples thereof include cobalt, molybdenum, and chromium. The supported amount of the antibacterial metal component is 0.01 to
It is about 70% by weight. The antibacterial polymer can be produced by chemically bonding an antibacterial metal component composed of a metal ion or a metal compound to a functional group of a hydrophilic polymer particle having a cross-linked structure and supporting it. The resin composition of the present invention contains the antibacterial polymer particles and a resin (such as a binder resin) and can be used as an antibacterial coating resin composition. This antibacterial resin composition can be prepared by mixing the antibacterial polymer particles with a resin (such as a binder resin).

[0007] In the present specification, "supporting" the antibacterial metal component means that the antibacterial metal component is held on the surface and / or inside the polymer particles as long as the antibacterial property is exhibited. “Chemical bond” and “chemical bond” are used to mean both ionic bonds and coordinate bonds, and may be simply referred to as “coordination”. Further, the “non-crosslinked hydrophilic polymer” and the “hydrophilic polymer having a crosslinked structure” may be simply referred to as “hydrophilic polymer”.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION [Hydrophilic polymer particles] Polymer particles are composed of a hydrophilic polymer having a functional group capable of coordinating an antibacterial metal component, and may be either a synthetic polymer or a natural polymer. You may. The hydrophilic polymer particles have a crosslinked structure, and are generally hardly soluble or insoluble in a solvent. The hydrophilic polymer particles functioning as a carrier include a hydrophilic unit and a functional group containing at least one atom selected from an oxygen atom, a nitrogen atom and a sulfur atom and capable of chemically bonding to an antibacterial metal component. It is composed of a coordinating unit having (particularly a coordinating group) and a crosslinking unit. In the hydrophilic polymer particles, the hydrophilic unit and the coordinating unit having a functional group may be the same or different.

As the hydrophilic unit, various hydrophilic fragments and segments can be used. For example, a carboxyl group-containing unit [formed of a carboxyl group or acid anhydride group-containing monomer such as (meth) acrylic acid and maleic anhydride]. Unit), a hydroxyl group-containing unit [a vinyl alcohol unit formed by hydrolysis of vinyl acetate, a unit formed of a hydroxyl group-containing monomer such as hydroxy C _2-3 alkyl (meth) acrylate], and an ether group-containing unit [vinyl A unit formed of an ether group-containing monomer such as C _1-4 alkyl ether, polyethylene glycol mono- or di (meth) acrylate, polyethylene glycol], a nitrogen-containing unit [vinylpyrrolidone, vinylpyridine,
A unit formed of a nitrogen-containing monomer such as (meth) acrylamide, methylol (meth) acrylamide, N, N-dialkylaminoalkyl (meth) acrylate]. The hydrophilic polymer may have a plurality of different hydrophilic units, and the hydrophilic units may form a salt if necessary.

Preferred hydrophilic units include those which form a water-soluble polymer and have an affinity for a hydrophobic resin. Such hydrophilic units include a nitrogen atom (particularly an amide group). Or a unit containing an N-substituted amide group (eg, a hydrophilic unit formed of (meth) acrylamide, N-substituted (meth) acrylamide, or the like). N-substituted (meta)
As acrylamide, for example, N-methyl (meth)
Acrylamide, N-ethyl (meth) acrylamide,
Examples include N-C _1-6 alkyl (meth) acrylamide such as N-butyl (meth) acrylamide, N-C _1-6 acyl (meth) acrylamide and the like. In addition, when the hydrophilic unit is formed of N-C _1-6 alkyl (meth) acrylamide such as N-butylacrylamide, the polymer particles can also be provided with temperature sensitivity.

In the coordinating unit, the functional group containing an oxygen atom (particularly, a coordinating group) includes, for example, a carboxyl group or a derivative thereof (acid halide group, acid anhydride group, etc.), a hydroxyl group, an acyl group. (C _1-4 acyl group such as formyl and acetyl group), carbonyl group, polycarbonyl group having acetylacetone structure, ether group,
Crown ether group, aromatic polyhydroxyl group containing catechol structure, aromatic hydroxycarbonyl group containing salicylic acid structure, polycarboxylic acid group containing phthalic acid structure, epoxy group, oxygen-containing heterocyclic group (furyl group, chromanyl group, etc.) And the like.

Examples of the functional group containing a nitrogen atom (particularly a coordinating group) include, for example, an amino group, a mono- or di-alkylamino group (such as a mono-C _1-4 alkylamino group, a di-C _1-4 alkylamino group), Azo group, amidino group, hydrazino group, hydrazono group, cyano group, nitrogen-containing heterocyclic group (pyrrolyl group, imidazolyl group, pyridyl group, bipyridyl group, pyrrolyl group, piperidinyl group, piperazinyl group, quinolyl group, benzimidazolyl group, phenanthrolyl And aza crown ether groups. In many cases, an amino group or an imino group is used as the nitrogen-containing functional group, and the nitrogen-containing functional group may be a heterocyclic group such as a pyridyl group.

Functional groups containing sulfur atoms (particularly coordinating groups)
As a mercapto group (thiol group), a thioxo group,
Thienyl group, thioacetyl group, alkylthionyl group, thiocarbamoyl group, sulfonyl group, thiocarboxyl group, sulfonic acid group (sulfo group), sulfinic acid group (sulfino group), thiourea group (thioureido group), thiacrown ether group, Examples thereof include a thioether group and a heterocyclic group (such as a thiophenyl group).

The hydrophilic polymer particles may have a functional group having a plurality of atoms selected from an oxygen atom, a nitrogen atom, a sulfur atom and the like, for example, a functional group containing an oxygen atom and a nitrogen atom. Examples of such a functional group include nitro group, ureido group, amino alcohol group such as aminohydroxyethyl group, aminophenol group, quinolino group, aminopolycarboxylic acid group such as imidinoacetic acid group, oxime group, amide Examples thereof include an oxime group and a heterocyclic group (such as a morpholino group and a morpholinyl group).

A plurality of the above functional groups can be combined. Since the strength of the bond with the metal ion or the metal compound varies depending on the type of the functional group, the release of the antibacterial metal component from the hydrophilic polymer particles can be controlled by using a plurality of different types of functional groups in combination.

The type of the functional group can be selected according to the type of the antibacterial metal component. Preferred functional groups include an oxygen-containing functional group [for example, a carboxyl group], a nitrogen-containing functional group [for example, a nitrogen-containing heterocyclic group (eg, imidazolyl group, pyridyl group, bipyridyl group, etc.)], a sulfur-containing functional group [thiol Group, thioureido group, etc.]. When such a functional group is combined with an antibacterial metal component (for example, a silver component), a complex can be effectively formed.

The crosslinking unit for introducing a crosslinking structure into the hydrophilic polymer particles comprises a condensable group or fragment such as self-crosslinked polymer particles (for example, cured or crosslinked particles of a thermosetting resin). Or a cross-linking agent. Crosslinked polymer particles have high heat resistance,
It exhibits high resistance to exposure to high temperatures (for example, about 300 ° C.) such as baking paints. As the cross-linking agent constituting the cross-linking unit, in the case of a polymer using a polymerizable unsaturated monomer as a raw material (vinyl polymerization type polymer), a polyfunctional polymerizable monomer [divinylbenzene, methylenebis (meth) acrylamide, ethylene Glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate,
Dipropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri or tetra (meth) acrylate, etc.] are used.

In the case of a hydrophilic polymer (condensation type or addition condensation type polymer) using a condensation or addition reactive monomer as a raw material,
As the cross-linking agent, a compound having two or more reactive functional groups with respect to the functional group of the polymer can be used. When the hydrophilic polymer has a plurality of carboxyl groups or acid anhydride groups,
Examples of the crosslinking agent include polyvalent metal ions (magnesium ions, aluminum ions, zirconium ions, etc.); polyisocyanates; polyamines; epoxy compounds having a plurality of epoxy groups; bisoxazoline compounds. When the hydrophilic polymer has a hydroxyl group, as a crosslinking agent, for example, a polyisocyanate; a polyvalent carboxylic acid or a reactive derivative thereof (acid halide, acid anhydride); a compound having a hydrolyzable silyl group (dichlorodimethylsilane, Dichlorotetramethyldisiloxane, methyltrimethoxysilane, methyltriethoxysilane, etc.); compounds having a plurality of methylol groups or alkoxymethyl groups (urea resins, melamine resins, etc.); bisoxazoline compounds. When the hydrophilic polymer has an amino group, an amide group or the like, for example, polyisocyanate; polycarboxylic acid or a reactive derivative thereof; a compound having a hydrolyzable silyl group; an epoxy compound having a plurality of epoxy groups; a bisoxazoline compound And the like can be used as a crosslinking agent.

The degree of crosslinking of the hydrophilic polymer particles is, for example, as follows:
0.1 to 30% by weight, preferably 0.5 to 20% by weight, more preferably 1 to 30% by weight in terms of a crosslinking unit (or crosslinking agent).
About 10% by weight.

The hydrophilic polymer particles having a crosslinked structure are formed of the above-mentioned coordinating unit having hydrophilicity (for example, a monomer containing a carboxyl group, a nitrogen-containing group such as a nitrogen-containing heterocyclic group, a mercapto group, etc.). Unit) and a crosslinking unit (for example, a unit formed by a crosslinking monomer such as a polyfunctional polymerizable monomer or a crosslinking agent)
A hydrophilic unit (a unit formed of a monomer such as (meth) acrylamide or N-substituted (meth) acrylamide) with the coordinating unit (for example, the carboxyl group, A copolymer or cocondensate of a unit formed of a monomer containing a nitrogen-containing functional group, a mercapto group, or the like) and a cross-linking unit (for example, a unit formed of a polyfunctional polymerizable monomer or the like) is included. .

These hydrophilic polymer particles may further comprise, as copolymerized units, for example, (meth) acrylic monomers such as alkyl (meth) acrylate, (meth) acrylonitrile, aromatic vinyl monomers such as styrene, and vinyl acetate. Or a unit formed of a halogen-containing monomer such as polyvinyl chloride or polyvinylidene chloride, or an olefin such as ethylene or propylene, and may be further modified if necessary. .

Preferred hydrophilic polymer particles include hydrophilic polymer gels (eg, a crosslinked polymer having a coordinating unit (crosslinked polyacrylic acid, crosslinked polyvinylpyridine, etc.), a crosslinked polymer having an acrylamide unit and a coordinating unit. Copolymer (acrylamide- (meth) acrylic acid copolymer having a cross-linked structure, acrylamide-vinylpyridine copolymer having a cross-linked structure, acrylamide-mercaptomethyl-substituted styrene copolymer having a cross-linked structure,
Acrylamide- (meth) acrylic acid-vinylpyridine copolymer having a crosslinked structure, etc.].

The concentration of the functional group (coordinating unit) of the hydrophilic polymer particles can be selected according to the amount of the antibacterial metal component carried. For example, 0.01 to 1 per gram of the polymer particles.
0 mmol, preferably about 0.1 to 5 mmol. The amount of the monomer having a coordinating unit is, for example, 5 to 100% by weight, preferably 10 to 10% by weight.
0% by weight, more preferably in the range of about 25 to 100% by weight.

The antimicrobial activity of the antimicrobial metal component is effectively exhibited.
The hydrophilic polymer particles may be porous.
No. The specific surface area of the porous particles is, for example, 10 to 1000.
m^Two/ G, preferably 50 to 1000 m^Two/ G, and more
Preferably 100 to 1000 m ^Two/ G.

The shape of the particulate hydrophilic polymer may be spherical, plate-like, rod-like, petal-like or the like. The average particle diameter of the hydrophilic polymer particles in a dry state, for example,
0.1 nm to 100 μm, preferably 1 nm to 30 μm
(For example, 1 nm to 5 μm), more preferably 5 nm to 5 nm.
About 10 μm (especially 10 nm to 1 μm),
It may be about 500 nm. The particle size of the hydrophilic polymer particles can be selected according to the application, but when nano-sized polymer particles are used, dispersibility in the resin composition, the content of the antibacterial metal component in the resin composition can be increased,
High antibacterial properties can be exhibited with a small amount of addition. Furthermore, the state in which the antibacterial metal component is carried on the hydrophilic polymer particles (for example, introduction of a plurality of functional groups having different coordination properties to the antibacterial metal component into the polymer particles by copolymerization, etc.), and different functional groups By mixing a plurality of polymer particles and controlling the degree of hydrophilicity of the polymer particles (for example, hygroscopicity and swelling of the polymer particles),
The release of the antibacterial metal component can be controlled according to the ambient humidity and the like, and a fast-acting or persistent antibacterial agent can be obtained.

[Antimicrobial Metal Component] An antimicrobial metal component is carried on the hydrophilic polymer particles by chemical bonding. In particular, the antibacterial metal component is chemically bonded to the hydrophilic polymer particles via the functional group (functional group including an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and the like). The antibacterial metal component can be composed of a metal ion and a metal compound having antibacterial properties, and these antibacterial metal components can be used alone or in combination of two or more. Examples of the metal ions having antibacterial properties include silver ions (silver (I) or (II) ions), platinum ions, copper ions, zinc ions, nickel ions, cobalt ions, molybdenum ions, and chromium ions. . Preferred antimicrobial metal ions are silver (I) ions, copper ions and zinc ions, especially silver ions.

The metal compounds having antibacterial properties include silver,
At least one metal compound selected from platinum, copper, zinc, nickel, cobalt, molybdenum and chromium can be exemplified, and usually, a metal compound reactive or coordinating with the functional group of the polymer can be used. The metal compound may be a metal complex, and the metal complex may be anionic, cationic or neutral. In the case of an anionic complex, the counter cation is preferably a quaternary ammonium having antibacterial properties (phenyldimethylalkylammonium, didecyldimethylammonium, cetyltrimethylammonium, tetramethylammonium, etc.).

Preferred metal compounds include silver compounds, for example, silver halide (AgCl, AgBr, etc.), halides and perhalates (AgClO ₄ , AgCl
O ₃ , AgBrO ₃ , AgIO _3, etc., inorganic acid salts (silver sulfate, silver nitrate, silver carbonate, etc.), organic acid salts (silver acetate, silver oxalate, etc.), complexes (dicyano complex, dithiosulfite complex, diammine complex) , Dichloro complexes, etc.). The antibacterial metal component (such as a silver component) coordinates with a functional group of the polymer to form a complex (such as a thiol complex, a thioureido complex, a pyridyl complex, a bipyridyl complex, a phenanthrolyl complex, or a histidyl complex). Good. Use of an antibacterial metal component that can coordinate to a polymer functional group can increase the content of the antibacterial metal component and maintain antibacterial activity for a long period of time. Further, even if the antibacterial activity is reduced, it can be easily regenerated by immersion in an aqueous solution containing an antibacterial metal ion.

The loading amount of the antibacterial metal component may be within a range that does not impair the antibacterial property. For example, it is 0.01 to 70% by weight, preferably 0.1% by weight of the total weight of the hydrophilic polymer particles in terms of metal. It is about 50% by weight, more preferably about 1 to 40% by weight, particularly about 5 to 40% by weight.

The preferred antimicrobial agent of the present invention includes, for example, a nitrogen-containing hydrophilic unit, a coordinating unit such as an oxygen-containing functional group, a nitrogen-containing functional group, a sulfur-containing functional group, and a crosslinking unit. Particle diameter 1 nm to 10 μm (for example, 1 nm to 3 μm, preferably 10 to 500 nm,
Especially about 50 to 500 nm) hydrophilic polymer particles;
An antibacterial silver component supported by a chemical bond (particularly a coordinate bond) with the functional group of the polymer particles. In this antibacterial agent, the supported amount of the antibacterial silver component is:
1 to 50% by weight (preferably 5 to 40%)
% By weight). The hydrophilic polymer particles may further contain an organic antibacterial agent, if necessary, in order to enhance the antibacterial activity.

[Method of Producing Antimicrobial Polymer Particles] The antimicrobial agent of the present invention can be prepared by chemically bonding an antimicrobial metal component to a functional group of the hydrophilic polymer particles and supporting it. The hydrophilic polymer particles can be prepared by using a conventional method such as pulverization and classification, suspension polymerization, emulsion polymerization and the like. A typical method for preparing the crosslinked hydrophilic polymer particles is a precipitation polymerization method, for example, using a polymerization initiator in a non-aqueous solvent (particularly, a mixed solvent of water and a hydrophilic solvent) to correspond to the coordinating unit. A method of polymerizing a monomer mixture composed of a monomer to be formed, a monomer corresponding to a hydrophilic unit, and a crosslinking agent for forming a crosslinked structure can be exemplified. In this method, the particle size of the hydrophilic polymer particles can be controlled by adjusting the type of the hydrophilic solvent and the ratio of water to the hydrophilic solvent, thereby efficiently producing hydrophilic polymer particles having a nano-order particle size. Can be done. Examples of the hydrophilic solvent include alcohols such as methanol, ethanol, isopropanol and butanol, ketones such as acetone, ethers such as dioxane and tetrahydrofuran, and mixed solvents thereof. The ratio between water and the hydrophilic solvent is, for example, the former / the latter = 1/99 to 7
0/30 (% by weight), preferably 3/97 to 50/50
(% By weight). In this precipitation polymerization method, the size of the produced particles can be controlled without using a dispersion stabilizer, and the particles can be easily washed and collected, and hydrophilic polymer particles can be obtained at low cost.

The crosslinked hydrophilic polymer particles are prepared by adding a solution of a hydrophilic polymer containing a functional group capable of coordinating an antimicrobial metal component to a poor solvent and mixing to form polymer particles in a medium. A method of curing by adding a cross-linking agent, a mixed solution of a cross-linking agent and a hydrophilic polymer is added and mixed in a poor solvent for the polymer to form polymer particles in a medium,
It can also be obtained by a curing method, a spray drying method of spray-drying a mixture of a crosslinking agent and a hydrophilic polymer, or the like. The crosslinked hydrophilic polymer particles of a thermosetting resin having self-crosslinking properties can be prepared in the same manner as described above without using a crosslinking agent.

The functional group to which the antimicrobial metal component can be chemically bonded may be derived from the above-mentioned monomer or cross-linking agent which is a raw material of the polymer, and is introduced into the formed polymer by utilizing a polymer reaction or the like. May be. As a method for introducing the functional group into the polymer using a polymer reaction, for example, a conventional method according to a method for preparing a metal ion-adsorbing resin such as a chelate resin can be adopted. For example, mercapto and bipyridyl groups are described in Ueyama, N, et al. Inorg. Chem. Acta. 8
9, 19-23 (1984). The imidazole group can be introduced, for example, by reacting a polymer having a chloromethyl group with, for example, histidine.

The antimicrobial metal component is supported on the polymer particles by, for example, swelling the polymer particles with a solvent as necessary, adding and mixing a solution containing the antimicrobial metal component, and chemically bonding the antimicrobial metal component to the polymer. It can be carried out. After supporting the antibacterial metal component, the polymer is washed and dried to obtain the antibacterial polymer particles of the present invention.

The antimicrobial polymer particles of the present invention exhibit high antimicrobial activity over a long period of time because the antimicrobial metal component and the hydrophilic polymer particles are chemically bonded. In particular, because it is composed of hydrophilic polymers, it has recently become responsive to environmental responsiveness in high-humidity environments where microorganisms can easily propagate, due to water absorption, particles swelling and releasing antibacterial metal components inside the particles. ing. In particular, in the case of fine particles (for example, nano-sized particles), the distance until the antibacterial metal component inside the particle reaches the particle surface is short, and the contact efficiency between the antibacterial metal component and bacteria or microorganisms is increased by increasing the particle surface area. Can be improved. Furthermore, it is also possible to regenerate the hydrophilic polymer particles having reduced antibacterial activity simply by dipping them in a solution (aqueous solution) containing an antibacterial metal component. Furthermore, the antibacterial metal component can be stably supported, and does not discolor even when irradiated with ultraviolet rays or the like. Moreover, since the carrier is an organic polymer, it has high affinity for both hydrophobic and hydrophilic organic polymers, high dispersibility of polymer particles, and can form a highly transparent antibacterial coating film. is there. Therefore, the antibacterial polymer of the present invention is useful for constituting an antibacterial resin composition in combination with a resin (for example, a resin used for an ultraviolet curable paint or a water-based paint).

[Antimicrobial Resin Composition] In the antimicrobial resin composition, the resin can be selected from a wide range according to the application. Examples of the resin include thermoplastic resins [olefin resins (polyethylene, polypropylene, polyethylene and modified polypropylene modified with carboxyl groups, acid anhydride groups, epoxy groups, etc.), acrylic resins (polymethyl methacrylate, containing carboxyl groups). Acrylic resin, hydroxyl group-containing acrylic resin, epoxy group-containing acrylic resin, etc., styrene resin (polystyrene, AS resin, ABS resin, copolymer of styrene and (meth) acrylic monomer, etc.), vinyl acetate Resins (polyvinyl acetate, ethylene-vinyl acetate copolymer, vinyl acetate-vinyl chloride copolymer, etc.), vinyl alcohol polymers (polyvinyl alcohol, ethylene-vinyl alcohol copolymer, etc.), vinyl chloride resins (poly Vinyl chloride, etc.), polyester resin (poly Alkylene terephthalate, polyalkylene naphthalate, copolymerized polyester resin, modified polyester resin, etc.), polyurethane resin, polyamide resin, rubber, etc.), thermosetting resin [epoxy resin, phenolic resin, urethane resin, unsaturated polyester resin, vinyl ester Resin, diallyl phthalate resin, silicone resin, amino resin (urea resin, melamine resin, etc.)], photocurable resin [photocurable oligomers such as epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, etc. And photo-curable monomers such as polyfunctional (meth) acrylates and nitrogen-containing monomers]. These resins can be used alone or in combination of two or more.
The resin may be a water-soluble resin or an organic solvent-soluble resin. Further, the resin can be used as an aqueous dispersion (emulsion, latex, etc.) or a non-aqueous dispersion (organosol, etc.).

The resin composition of the present invention includes an antibacterial molding resin composition containing a molding resin and a resin composition containing an adhesive resin, which are used for molding such as extrusion molding and injection molding. Preferably, the coating resin composition includes a coating resin (binder resin) such as a paint. When a coating film (coating film) containing antibacterial polymer particles is formed, high antibacterial activity can be effectively maintained on the surface of the product for a long period of time. The form of the coating resin composition is a powder coating agent composed of a powder, an aqueous coating agent in which the solvent is composed of an aqueous solvent,
The solvent may be any of a solvent type coating agent composed of an organic solvent and a non-solvent type coating agent such as an ultraviolet curable paint. The amount of antibacterial polymer particles used is
The resin can be selected from a wide range.
0.01 to 200 parts by weight, preferably 0.1 to 100 parts by weight, more preferably 0.5 to 5 parts by weight with respect to 00 parts by weight.
It is about 0 parts by weight. The thickness of the coating film (antibacterial layer) can be appropriately selected, for example, from the range of 1 to 500 μm, preferably about 5 to 300 μm.

The antimicrobial resin composition of the present invention may contain various additives such as stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, etc.), plasticizers, antistatic agents, flame retardants, dispersants, It may contain a surfactant, a filler, a colorant, a viscosity modifier, a preservative, a fungicide, a leveling agent, and the like.

The antibacterial resin composition (or resin composition for coating) can be prepared by mixing the antibacterial polymer particles, a resin or a binder resin, and if necessary, a solvent or an additive. For the preparation of the resin composition, depending on the form of the resin composition, a conventional apparatus, if it is, a kneading machine,
Dispersers, mixers, etc. can be used.

The coating film can be formed by applying a coating resin composition to a substrate by a conventional coating method and drying (heating and curing if necessary) or irradiating light (ultraviolet light or the like). As the substrate, paper, wood, plastic, ceramics including glass, metal, and the like can be used.

When the antimicrobial polymer particles (antimicrobial agent) of the present invention are used in a coating agent such as a paint, the antimicrobial agent can be uniformly and easily dispersed, and the dispersion stability is high.
It is possible to prevent sedimentation and separation from occurring. Therefore, the activity of the antibacterial agent can be effectively exhibited even with a small amount of the antibacterial agent.
Furthermore, since it has high affinity and adhesion to an organic binder, a coating film having high mechanical strength and high transparency can be formed.

[0042]

According to the present invention, since the antibacterial metal component of the antibacterial agent is chemically bonded to the hydrophilic polymer particles having a crosslinked structure, despite the use of the inorganic antibacterial metal component,
High antibacterial activity can be expressed effectively and over a long period of time, and the durability is high. In addition, since the polymer particles are hydrophilic, antibacterial properties can be effectively exhibited with an increase in humidity or moisture, and thus have environmental responsiveness. Further, even when used as a resin composition such as a coating agent, the antibacterial agent is excellent in dispersibility, affinity with organic polymers, and film properties.

[0043]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples. Example 1 [Preparation of Crosslinked Hydrophilic Polymer Fine Particles] Acrylamide 4
g (0.056 mol, 72.2 mol%), methylene bisacrylamide 2.4 g (0.0156 mol, 20.1 mol%)
Mol.) And 1.6 g (0.006 mol, 7.7 mol%) of 4- (N, N-diethyldithiocarbamate) styrene were mixed with 86 ml of ethanol and 6 ml of water.
To the mixed solvent of azobisisobutyronitrile 0.1.
17 g at 60 ° C. in an argon atmosphere using
Precipitation polymerization was carried out for an hour. In this reaction, after heating to a temperature of 60 ° C., about 2.5 hours later, the polymerization system became cloudy and polymer particles were generated.

[Hydrolysis] Ethanol 1 was added to the reaction mixture.
A mixed solution of 00 ml, 50 ml of water and 2 g of sodium hydroxide was added thereto, and the mixture was hydrolyzed by stirring at 70 ° C. for 5 hours in an argon atmosphere, then centrifuged, and the precipitated particles were mixed with a mixed solvent of 100 ml of ethanol and 100 ml of water. Washed twice. In order to generate a mercapto group, the precipitated particles were added to water, the pH was adjusted to about 5 by adding 1N-hydrochloric acid, and the mixture was stirred for 24 hours to hydrolyze. The mixture was then centrifuged and the precipitated particles were washed with 100 ml of ethanol and 1 ml of water.
Wash three times with 00 ml of the mixed solvent, and further add 150 ml of water.
And washed twice.

[Preparation of Silver Complex-Supported Polymer Particles] A mixture of 1.05 g (0.006 mol) of silver nitrate and 150 ml of water was added to the washed precipitated particles, and the mixture was stirred at room temperature for 2 hours. Colored orange. The mixture was centrifuged, and the precipitated particles were washed with 150 ml of water once with 150 ml of methanol.
After washing twice with water and drying under reduced pressure, silver complex-carrying polymer particles (average particle diameter of about 60 to 90 nm) were obtained (yield 7.8 g (in terms of dry solid content), water content 14.
9% by weight, silver content 22.8% by weight, yield 89.9
%).

Example 2 [Preparation of Crosslinked Hydrophilic Polymer Fine Particles] Acrylamide 4
g (0.056 mol), 2.4 g (0.0156 mol) of methylenebisacrylamide, and 1.6 g (0.0152 mol) of 4-vinylpyridine were added to a mixed solvent of 86 ml of ethanol and 6 ml of water. Then, precipitation polymerization was carried out using 0.05 g of azobisisobutyronitrile in an argon atmosphere at a temperature of 60 ° C. for 17 hours. In this reaction, about 1.5 hours after heating to a temperature of 60 ° C., the polymerization system became cloudy and polymer particles were formed. The reaction mixture was centrifuged, and the precipitated particles were washed twice with 150 ml of water.

[Preparation of Silver Complex-Supported Polymer Particles] 2.58 g (0.0152 mol) of silver nitrate was added to the washed precipitated particles.
Of water and 150 ml of water were added, and the mixture was stirred at room temperature for 2 hours. The mixture is centrifuged and the precipitated particles are treated with methanol 150
After washing twice with water and drying under reduced pressure, silver complex-carrying polymer particles (average particle size of about 90 to 120 nm) were obtained (yield 8.6 g (in terms of dry solid content), water content 1).
3.3% by weight, silver content 35.2% by weight).

Example 3 [Preparation of Crosslinked Hydrophilic Polymer Fine Particles] 4.5 g (0.063 mol) of acrylamide, 2.4 g (0.0156 mol) of methylenebisacrylamide, and 1.1 g (0.0152 mol) of acrylic acid ) Was added to a mixed solvent of 86 ml of ethanol and 6 ml of water, and precipitation polymerization was carried out using 0.05 g of azobisisobutyronitrile in an argon atmosphere at a temperature of 60 ° C. for 17 hours. In this reaction, after heating to a temperature of 60 ° C., about 0.5 hour later, the polymerization system became cloudy and polymer particles were generated. The reaction mixture was centrifuged, and the precipitated particles were washed twice with 150 ml of water.

[Preparation of Silver Complex-Supported Polymer Particles] 2.58 g (0.0152 mol) of silver nitrate was added to the washed precipitated particles.
Of water and 150 ml of water were added, and the mixture was stirred at room temperature for 2 hours. The mixture is centrifuged and the precipitated particles are treated with methanol 150
After washing twice with water and drying under reduced pressure, silver complex-carrying polymer particles (average particle size of about 90 to 120 nm) were obtained (yield 11.5 g (in terms of dry solid content), water content 1).
3.9% by weight, silver content 25.7% by weight).

[Evaluation of Antibacterial Activity] Antibacterial activity was evaluated by the minimum alienation concentration (MIC, ppm) according to the standard method of the Japanese Society of Chemotherapy as follows. (1) Sample Silver complex-carrying polymer particles obtained in Examples 1 to 3 Comparative Example 1: Commercially available silver silica gel antibacterial agent (silver ion amount: about 3% by weight) Comparative Example 2: Commercially available silver zeolite antibacterial agent ( (Amount of silver ions: about 3% by weight) (2) Strain used Staphylococcus: Staphylococcus aureus
lococcus aureus) 209P JC-1 Escherichia coli: Escherichia coli NIHJ J
C-2 (3) Medium A broth medium for sensitivity measurement and an agar medium for sensitivity disk were used. (4) Test method Since each specimen was insoluble, it was suspended in purified water to prepare a suspension having a concentration 10 times the test concentration. In the test, 1 part by volume of the test suspension was mixed with 9 parts by volume of the culture medium. On the other hand, test bacteria were cultured overnight at 37 ° C. using a sensitive bouillon medium, and then appropriately diluted with the same medium to prepare a test bacterial solution of 10 ⁶ cfu / ml. Table 1 shows the results
Shown in

[0051]

[Table 1] As is clear from Table 1, the antibacterial polymer particles of Examples 1 to 3 exhibit higher antibacterial properties than commercial products.

Example 4 1 part by weight of the silver complex-carrying polymer particles obtained in Example 2 was mixed with 99 parts by weight of an ultraviolet-curable paint (Aronix UV-3701 manufactured by Toagosei Co., Ltd.). The dispersion mixture was applied to a polyethylene terephthalate film with a bar coater, and irradiated with ultraviolet light using a high-pressure mercury lamp.
Irradiation was performed for 0 minutes to form a cured film. Comparative Example 3 Comparative Example 2 was conducted in place of the silver complex-supported polymer particles of Example 2.
A cured film was formed in the same manner as described above except that the antibacterial agent was used.

Example 5 1 part by weight of the silver complex-carrying polymer particles obtained in Example 2 was mixed with 99 parts by weight (in terms of solid content) of an aqueous emulsion paint (Aron NS-1200, manufactured by Toagosei Co., Ltd.). Then, the obtained dispersion mixture was applied to a polyethylene terephthalate film with a bar coater, and dried at room temperature to form a coating film. Comparative Example 4 Comparative Example 2 was repeated in place of the silver complex-carrying polymer particles of Example 2.
A coating film was formed in the same manner as described above except that the antibacterial agent was used.

Then, the antibacterial property of the coating film against the strain was examined as follows. Staphylococcus aureus 209P JC-
1) and Escherichia coli (Escherichia col
i) After culturing NIHJ JC-2) in a normal broth medium (NB, Eiken) at 37 ° C. for 18 to 20 hours, appropriately dilute it in a normal broth medium (NB, Eiken) diluted to a concentration of 1/500, A test bacterial solution of 10 ⁵ cfu / ml was prepared. Diameter 3
1 ml of the test bacterial solution is placed in a 5 mm mesh plastic dish (Sumilon), and the sample coating film is brought into contact with the test bacterial solution with the film surface of the sample down, the lid is placed on the Petri dish, and sealed at room temperature (25 ° C.). For 24 hours. As a control, the same operation as above was performed using only the bacterial solution (no treatment). The bactericidal action at the start and the bacterium count after 24 hours were measured by a pour method using a normal agar medium (NA, Eiken) and evaluated by the change in the bacterium count. Table 2 shows the antibacterial properties of the coatings.

[0055]

[Table 2] As is clear from Table 2, the antibacterial polymer particles of the examples exhibit higher antibacterial properties than commercial products. In addition,
The cured film formed in Example 4 was a highly transparent cured film except that it was colored slightly yellow. On the other hand, the cured film formed in Comparative Example 3 was colored red-brown and the transparency was also reduced.
As described above, the antibacterial polymer particles of Example 2 are stable to ultraviolet light probably because silver ions exist as a complex. Further, the antibacterial polymer particles of Example 2 had a very small particle diameter and were formed of an organic polymer, so that there was no difference in the refractive index from the base resin (ultraviolet curable resin), and the particles were transparent. High in nature. On the other hand, Comparative Example 2
The antibacterial agent of (1) has a low silver ion stability and is colored, has a large particle diameter of about 1 to 3 μm, and has a large difference in refractive index from the base resin, and therefore has low transparency.

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Claims (9)

[Claims] 1. An antibacterial polymer particle in which an antibacterial metal component composed of a metal ion or a metal compound is chemically bonded to a polymer particle and supported, wherein the polymer particle is a hydrophilic unit. A unit having at least one atom selected from an oxygen atom, a nitrogen atom and a sulfur atom, and having a functional group capable of chemically bonding to an antibacterial metal component, and a crosslinking unit. Antibacterial polymer particles composed of a hydrophilic polymer. 2. A hydrophilic polymer having a cross-linked structure, wherein a hydrophilic unit containing a nitrogen atom and at least one selected from a carboxyl group, a pyridyl group and a mercapto group are used.
The antimicrobial polymer according to claim 1, comprising a hydrophilic polymer gel including a unit having two functional groups and having a functional group capable of chemically bonding to an antimicrobial metal component, and a crosslinking unit. particle. 3. An average particle diameter of the polymer particles is 0.1 nm.
The antibacterial polymer particle according to claim 1, which has a thickness of from 100 to 100 µm. 4. The antibacterial polymer particles according to claim 1, wherein the antibacterial metal component is at least one metal component selected from the group consisting of silver, platinum, copper, zinc, nickel, cobalt, molybdenum and chromium. 5. The antibacterial polymer particles according to claim 1, wherein the supported amount of the antibacterial metal component is 0.01 to 70% by weight in terms of metal. 6. An average particle diameter of 1 nm having a nitrogen-containing hydrophilic unit, a unit having an oxygen-containing functional group, a nitrogen-containing functional group or a sulfur-containing functional group, and a crosslinking unit.
A hydrophilic polymer particle of 10 μm and an antibacterial silver component supported by being chemically bonded to the functional group of the polymer particle, and the supported amount of the antibacterial silver component is calculated as silver.
2. The antibacterial polymer particles according to claim 1, which accounts for 1 to 50% by weight of the whole. 7. An antibacterial metal component composed of a metal ion or a metal compound, which contains at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a phosphorus atom, and has a crosslinked structure. A method for producing antibacterial polymer particles which are chemically bonded to and supported on functional groups of hydrophilic polymer particles. 8. A resin composition comprising the antibacterial polymer particles according to claim 1 and a resin. 9. A method for producing an antibacterial resin composition, comprising mixing the antibacterial polymer particles according to claim 1 with a resin.