JP2022145100A - Antibacterial/antiviral fine particle, antibacterial/antiviral composition and antibacterial/antiviral article - Google Patents

Abstract

To provide a fine particle having antibacterial/antiviral metal ions supported thereon, where the fine particle keeps antibacterial/antiviral properties for a long time and has excellent dispersibility in an organic solvent.SOLUTION: A antibacterial/antiviral fine particle comprises: a fine particle carrier having nonionic functional groups coordinatable to metal ions on its surface and inside it; and metal ions coordinated with the nonionic functional groups existing on the surface of and inside the fine particle carrier, the metal ions having one or both of antibacterial and antiviral properties.SELECTED DRAWING: None

Description

The present disclosure provides antibacterial and/or antiviral microparticles (hereinafter also referred to as “antibacterial/antiviral microparticles”), antibacterial and/or antiviral compositions (hereinafter also referred to as “antibacterial/antiviral compositions”), and antibacterial and/or antiviral articles (hereinafter also referred to as "antibacterial/antiviral articles").

Particles such as silicone particles are widely used as additives for synthetic resins, waxes, paints, inks, adhesives, cosmetics, films and sheets. Moreover, imparting various functions to the particles by supporting metal ions on the particles has been studied. For example, it has long been known that metal ions represented by silver ions have antibacterial properties, and antibacterial agents and antibacterial processed products utilizing the antibacterial properties of silver ions are widely used. It has also been confirmed that metal ions having such antibacterial properties have antiviral properties.

Conventionally, as a method for supporting particles with metal ions for imparting the above functions, a method is known in which a part or all of the ion-exchangeable ions in an inorganic particle carrier are replaced with metal ions by an ion exchange reaction. there is Generally, silicates such as zeolite and silica gel, or phosphates such as calcium phosphate and hydroxyapatite are used as inorganic particle carriers. The metal ions carried on the inorganic particle carrier are gradually released from the inside of the inorganic particle carrier, and the antibacterial and/or antiviral properties (hereinafter also referred to as "antibacterial/antiviral properties") based on the metal ions are continuously exhibited. do.

For example, Patent Document 1 discloses antibacterial zeolite particles in which some or all of the ion-exchangeable ions in the zeolite particles are replaced with silver ions and at least one kind of amine ions.

A method has also been proposed in which metal ions having antibacterial and antiviral properties are supported on particle carriers by complex formation instead of ion exchange reaction. Patent Document 2 discloses antibacterial particles in which a metal complex compound in which a specific ligand is coordinated to a metal ion is supported on a carrier particle. Patent Document 3 discloses particles obtained by coating silica gel particles with a polymer that forms a complex with silver ions.

JP-A-1-286913 JP-A-6-206803 JP 2018-076522 A

According to the study by the present inventors, it was found that the zeolite particles of Patent Document 1 have low dispersibility in organic solvents. Further, for example, fine particles whose primary particles have a small particle size tend to agglomerate over time to form secondary particles. When fine particles having a high cohesive force are blended in an organic solvent, the fine particles in the state of primary particles do not disperse in the organic solvent, but form secondary particles or aggregates thereof. Therefore, it becomes difficult to prepare a mixture in which the fine particles are well dispersed in the organic solvent, and the fine particles as an additive may not exhibit their functions, such as antibacterial and antiviral properties, well.

In addition, in the particles of Patent Documents 2 and 3, since metal ions are supported only on the surface of the particle carrier, it is considered that the amount of supported metal ions is not sufficient, or the antibacterial and antiviral properties are not sufficient. be done. This is believed to be due to the absence of groups coordinating with metal ions inside the particle carrier.

One object of the present disclosure is to provide fine particles carrying metal ions having antibacterial and antiviral properties, which are excellent in antibacterial and antiviral properties and excellent in dispersibility in organic solvents.

In order to solve the above-mentioned problems, the present inventors focused on supporting metal ions having antibacterial and antiviral properties on fine particle carriers by complex formation instead of ion exchange reaction. As a result, the present inventors have found microparticle carriers having nonionic functional groups capable of coordinating metal ions not only on the surface but also on the interior, and nonionic functional groups present on the surface and in the interior of the microparticle carriers. It has been found that fine particles containing the above-mentioned metal ions are excellent in antibacterial/antiviral properties and dispersibility in organic solvents.

The antibacterial/antiviral microparticles of the present disclosure are arranged by microparticle carriers having nonionic functional groups capable of coordinating metal ions on the surface and inside, and nonionic functional groups present on the surface and inside of the microparticle carriers. and metal ions that have either or both antibacterial and antiviral properties.

According to the present disclosure, fine particles supporting metal ions having antibacterial and antiviral properties, which are excellent in antibacterial and antiviral properties (and, for example, their persistence), and excellent in dispersibility in organic solvents are provided. can do.

FIG. 1 is a schematic diagram showing a typical example of microparticles of the present disclosure. 2 is an SEM image of the microparticles of Example 1. FIG. 3 is the result of SEM-EDX of the microparticles of Example 1. FIG. 4 is the result of SEM-EDX of the microparticles of Example 7. FIG.

In the present disclosure, "antibacterial" refers to the property of killing or damaging one or both of bacteria and fungi, or the property of continuously suppressing the growth and proliferation of one or both of bacteria and fungi. . Bacteria include, for example, Staphylococcus, Escherichia coli, Salmonella, Pseudomonas aeruginosa, Vibrio cholerae, Shigella, Anthrax, Mycobacterium tuberculosis, Clostridium botulinum, Clostridium tetani, and Streptococcus. Fungi (or molds) include, for example, Trichophyton, Candida and Aspergillus.

In the present disclosure, the term “antiviral property” refers to the property of inactivating a virus by denaturing or damaging a protein that constitutes the capsid or envelope of the virus. Viruses include, for example, norovirus, influenza virus, adenovirus, coronavirus, measles virus, rubella virus, hepatitis virus, herpes virus, and HIV.

[Antibacterial/antiviral microparticles]
The antibacterial/antiviral microparticles of the present disclosure are
a fine particle carrier having a nonionic functional group (hereinafter also referred to as "functional group (L)") capable of coordinating with metal ions on its surface and inside;
and metal ions having antibacterial and antiviral properties coordinated by functional groups (L) existing on the surface and inside of the fine particle carrier. Hereinafter, unless otherwise specified, metal ions refer to metal ions having antibacterial and antiviral properties.

Functional groups (L) function as ligands for metal ions. The functional group (L) coordinates to the metal ion to form a complex, so that the metal ion is well supported by the fine particle carrier. Since the functional group (L) is contained not only on the surface of the fine particle carrier but also on the inside, the metal ions are favorably supported not only on the surface of the fine particle carrier but also inside.

Since the fine particles have a nonionic functional group as a functional group exposed on the surface of the fine particle carrier, they exhibit good dispersibility in organic solvents and resins. Since the fine particles have metal ions supported not only on the surface of the fine particle carrier, but also inside the fine particles, it is believed that they continuously exhibit antibacterial and antiviral properties based on the metal ions.

Examples of the organic solvent include organic solvents described later. Examples of the resin (matrix resin) include polyolefins such as polyethylene, polypropylene and cyclic polyolefins; polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate; Polymers, styrenic resins such as polystyrene; polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyacrylonitrile, polyamide, polyimide, polyamideimide, (meth)acrylic resin, (meth)acrylic Photocurable resins, polycarbonates, polyarylphthalates, polysulfones, polyethersulfones, polyphenylene sulfides, polyurethanes, acetal resins, cellulose resins, fluorine resins, phenolic resins, melamine resins, epoxy resins, unsaturated polyester resins and silicone resins. . In the present specification, (meth)acryl is used as a generic term for acryl and methacryl, and (meth)acryloyl is used as a generic term for acryloyl and methacryloyl.

The particle size of the antibacterial/antiviral microparticles is appropriately selected according to its use.
In one embodiment, the average primary particle size of the antibacterial/antiviral microparticles of the present disclosure is preferably 10 nm or more and 500 nm or less, more preferably 10 nm or more and 400 nm or less, and even more preferably 10 nm or more and 300 nm or less. When high transparency is required as in the case of dispersing the antibacterial/antiviral microparticles in a resin, the average primary particle diameter of the antibacterial/antiviral microparticles is preferably 10 nm or more and 100 nm or less. Aggregation of fine particles in an organic solvent is suppressed in spite of their small particle size. Therefore, for example, a composition containing fine particles and an organic solvent can be used to form a coating film with excellent transparency.

The average primary particle size of the antibacterial/antiviral microparticles is measured using a scanning electron microscope (SEM). Specifically, 100 microparticles in the SEM image are randomly selected, the average value of the major diameters of the primary particles is obtained, and the number average value of the major diameters is taken as the average primary particle diameter of the antibacterial/antiviral microparticles. do.

<Fine particle carrier>
The microparticle carrier has one or more functional groups (L) on its surface and inside. The fine particle carrier has functional groups (L) not only on the surface of the carrier but also inside the carrier. Accordingly, the antibacterial and antiviral microparticles contain metal ions coordinated by functional groups (L) not only on their surface but also on their interior.

The functional group (L) is not particularly limited as long as it is a nonionic functional group capable of forming a complex by coordinating with a metal ion. Examples include an ethylenically unsaturated bond (C=C); ₆ H ₆ ); hydroxy group (--OH), carbonyl group (>C(=O)), mercapto group (--SH), amino group (--NH ₂ ), isothiocyanate group (--N=C =S) and nitro groups (--NO ₂ ). Among these, an ethylenically unsaturated bond is preferable from the viewpoint of imparting appropriate hydrophobicity to the fine particle carrier and further improving the dispersibility of the fine particles in the organic solvent and the resin.

When the fine particle carrier has an anionic functional group such as a carboxy group, a sulfo group and a sulfate group instead of a nonionic functional group, the fine particle carriers aggregate due to the ionic interaction between the metal ion and the anionic functional group. There is a tendency. Therefore, such fine particle carriers tend not to exhibit good dispersibility in dispersion media such as organic solvents. In contrast, when the fine particle carrier has a nonionic functional group (L), the aggregation of the fine particle carriers is suppressed. Therefore, such a fine particle carrier exhibits good dispersibility in a dispersion medium such as an organic solvent.

In one embodiment, the particulate carrier has groups containing functional groups (L), such as groups containing ethylenically unsaturated bonds (hereinafter also referred to as "ethylenically unsaturated groups"). Examples of ethylenically unsaturated groups include alkenyl groups such as vinyl group (-CH=CH ₂ ) and allyl group (-CH ₂ -CH=CH ₂ ); acryloyl group (-C(=O)-CH=CH ₂ ), a methacryloyl group (-C(=O)-C( _CH3 )= _CH2 ), an acryloyloxyalkyl group (-ROC(=O)-CH= _CH2 )) and a methacryloyloxyalkyl group (--R--O--C(=O)--C(CH ₃ )=CH ₂ ). In the formula, R is an alkanediyl group. Among these, an alkenyl group is preferable, and a vinyl group and an allyl group are more preferable, from the viewpoints of coordinating ability to metal ions having antibacterial and antiviral properties and easiness in producing fine particle carriers.

Although the material of the fine particle carrier is not particularly limited, it is preferably an organic-inorganic hybrid polymer. The inorganic component of the organic and inorganic hybrid polymer constitutes the backbone of the particulate carrier. The organic component of the organic and inorganic hybrid polymer enhances the dispersibility of the particulate carrier in organic solvents and resins. At least a portion of the organic component is a group containing a functional group (L).

The organic-inorganic hybrid polymer is, in one embodiment, an organopolysiloxane in which silicon atoms (Si) having organic groups are linked by siloxane bonds (≡Si—O—Si≡). That is, the particulate carrier, in one embodiment, is an organopolysiloxane particulate having groups containing functional groups (L).

Examples of the organopolysiloxane include the average unit formula (1):
(R13SiO1/ ² ) _a (R12SiO2 _{/ 2} ) _b ( _R1SiO3 ^/ ₂ ) _c ( _SiO4/ ² _{) d}
A polymer having

In the average unit formula (1), each R ¹ is independently a monovalent organic group, preferably a monovalent ethylenically unsaturated group or a monovalent hydrocarbon group (excluding an ethylenically unsaturated group ), or monovalent substituted hydrocarbon groups (excluding ethylenically unsaturated groups). The number of carbon atoms in R ¹ is preferably 1 or more and 8 or less, more preferably 1 or more and 6 or less. The monovalent substituted hydrocarbon group has a hydrocarbon group as a basic skeleton, and at least one functional group selected from the group consisting of, for example, a hydroxy group, a mercapto group, an amino group, an isothiocyanate group, a nitro group and a carbonyl group. including. R ¹ is preferably a monovalent ethylenically unsaturated group or a monovalent hydrocarbon group, more preferably a monovalent ethylenically unsaturated group.

Monovalent ethylenically unsaturated groups include, for example, alkenyl groups such as vinyl groups, allyl groups, butenyl groups, pentenyl groups and hexenyl groups. The number of carbon atoms in the alkenyl group is preferably 2 or more and 8 or less, more preferably 2 or more and 6 or less, and still more preferably 2 or more and 3 or less. The monovalent ethylenically unsaturated group also includes a (meth)acryloyloxyalkyl group, that is, a group represented by the formula: -R ¹² -OC(=O)-CR ¹¹ =CH ₂ , specifically , acryloyloxypropyl group and methacryloyloxypropyl group. In the formula, R ¹¹ is a hydrogen atom or a methyl group, R ¹² is an alkanediyl group, preferably an alkanediyl group having 1 to 5 carbon atoms.

Among the monovalent ethylenically unsaturated groups, an alkenyl group is preferred, a vinyl group and an allyl group are preferred, and a vinyl group is more preferred.

Examples of monovalent hydrocarbon groups include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group and heptyl group; aryl groups such as phenyl group, tolyl group and xylyl group; Aralkyl groups such as benzyl and phenethyl groups are included. The number of carbon atoms in the monovalent hydrocarbon group is preferably 1 or more and 8 or less, more preferably 1 or more and 5 or less, and still more preferably 1 or more and 3 or less.

Monovalent substituted hydrocarbon groups include, for example, a 3-mercaptopropyl group (--(CH ₂ ) ₃ --SH) and a 3-aminopropyl group (--(CH ₂ ) ₃ --NH ₂ ).

R ¹ is preferably each independently an alkyl group or an alkenyl group, more preferably each independently an alkyl group having 1 to 3 carbon atoms, a vinyl group or an allyl group, from the viewpoint of microparticulation; A methyl group or a vinyl group is preferred.

However, in one organopolysiloxane molecule having the average unit formula (1), at least a portion of R ¹ is a group containing a functional group (L) such as a monovalent ethylenically unsaturated group, an aryl group or an aralkyl group. is preferably a monovalent ethylenically unsaturated group, more preferably an alkenyl group. The total ratio of monovalent ethylenically unsaturated groups, aryl groups, or aralkyl groups is preferably 50 mol% or more, more preferably 60 mol% or more, and even more preferably 60 mol% or more, based on all R ¹ in one organopolysiloxane molecule. is 70 mol % or more, more preferably 80 mol % or more, particularly preferably 90 mol % or more. A monovalent ethylenically unsaturated group, an aryl group or an aralkyl group is a hydrophobic group containing a nonionic functional group capable of coordinating to a metal ion.

a, b, c and d in the average unit formula ( ¹ ) are respectively the constituent units (R ¹³ SiO _1/2 ), (R _{12 SiO 2/2 )} , (R ¹ _{SiO 3/2 )} and ( SiO _4/2 ) represents the average molar fraction. The sum of a, b, c and d, which is the sum of the mole fractions of each structural unit, is 1.

a is the mole fraction of siloxane units represented _{by R 13 SiO 1/2} ⁽ _M units). a is 0 or more and 0.5 or less, preferably 0.4 or less, more preferably 0.3 or less, still more preferably 0.2 or less, and particularly preferably 0.1 or less.

b is the mole fraction of siloxane units represented by R ¹ ₂ SiO _2/2 (D units). b is 0 or more and 0.5 or less, preferably 0.4 or less, more preferably 0.3 or less, still more preferably 0.2 or less, and particularly preferably 0.1 or less.

c is the mole fraction of siloxane units represented by R ¹ SiO _3/2 (T units). c is 0.3 or more and 1 or less, preferably 0.4 or more, 0.5 or more, or 0.6 or more, more preferably 0.7 or more, still more preferably 0.8 or more, and particularly preferably 0.8 or more. 9 or more.

d is the mole fraction of siloxane units represented by SiO _4/2 (Q units). d is 0 or more and 0.7 or less, preferably 0.6 or less, 0.5 or less, or 0.4 or less, more preferably 0.3 or less, still more preferably 0.2 or less, and particularly preferably 0.2 or less. 1 or less.

The sum of c and d representing the sum of branched structural units is preferably 0.6 or more, more preferably 0.7 or more, even more preferably 0.8 or more, and particularly preferably 0.9 or more.

When the organopolysiloxane has the structural unit (R ¹³ SiO _1/2 ) in the average unit formula ( ₁ ), it may have only one type of the structural unit, or may have two or more types of the structural unit. The same applies to the structural units (R ¹ ₂ SiO _2/2 ) and (R ¹ SiO _3/2 ) in the average unit formula (1).

The organopolysiloxane may have structural units in which at least part of R ¹ in each structural unit is replaced with R ² O. In said formula, ^R2 is a hydrogen atom or an alkyl group. R ² O means a hydroxy group or an alkoxy group bonded to a silicon atom contained in the organopolysiloxane skeleton. Alkyl groups include, for example, methyl, ethyl and propyl groups. The number of carbon atoms in the alkyl group is preferably 1 or more and 3 or less.

The amount of the structural unit in which at least part of the R ¹ in each structural unit is replaced with R ² O is the sum of the molar fractions of the structural units, with respect to the sum of 1 of a, b, c and d is preferably 0 or more and 0.10 or less, more preferably 0 or more and 0.05 or less, and still more preferably 0 or more and 0.03 or less. The alkoxy group in this structural unit is, for example, an alkoxy group that is a hydrolyzable group contained in an alkoxysilane described later and remains in the molecule without hydrolysis/polycondensation. The hydroxy group in this structural unit is, for example, a hydroxy group remaining in the molecule without polycondensation after hydrolysis of the alkoxy group.

Organopolysiloxanes are preferably silsesquioxanes. In the present specification, silsesquioxane is an organopolysiloxane having a main chain skeleton composed of Si—O bonds, containing (R ¹ SiO _3/2 ) units as main structural units, and having c of 0.7 or more. is. The structure of silsesquioxane includes, for example, a random structure, a complete cage structure, an incomplete cage structure and a ladder structure. Oxane is preferred.

The fine particle carrier preferably has a pore structure that serves as a passage for metal ions, which will be described later. The size of the pores is not particularly limited, but is, for example, 0.1 nm or more and 1 nm or less. It is preferred that the particulate support typically have micropores comparable to conventional zeolite particles. Pore size and pore distribution are determined by gas adsorption methods. The pore structure can be formed by a method for producing fine particles, which will be described later.

The shape of the fine particle carrier does not have to be strictly spherical because it has little effect on the antibacterial/antiviral properties. Virtual shapes formed by projecting particulate carriers onto a plane include, for example, geometric shapes such as circles, ellipses, triangles and squares; and irregular shapes.

The microparticle carrier and antimicrobial/antiviral microparticles of the present disclosure, in one embodiment, are insoluble in water and organic solvents. "Insoluble in water and organic solvents" means that the fine particle carriers and the fine particles maintain their particle shape when the fine particle carriers and the fine particles are immersed in water or an organic solvent.

Examples of the organic solvent include alcohol solvents such as methanol, ethanol, 2-propanol and n-butanol; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono Glycol solvents such as butyl ether, propylene glycol monomethyl ether and ethylene glycol monoethyl ether acetate; ester solvents such as methyl acetate, ethyl acetate and butyl acetate; hydrocarbon solvents such as n-hexane, benzene, toluene and xylene; methylene chloride and chloroform. ether solvents such as tetrahydrofuran; nitrogen-containing solvents such as acetonitrile and N,N-dimethylformamide; and sulfur-containing solvents such as dimethylsulfoxide.

<Metal ion>
The antibacterial/antiviral microparticles of the present disclosure contain metal ions that are coordinated by functional groups (L) present on the surface and inside of the microparticle carrier to form a complex. Metal ions in the present disclosure have antibacterial and antiviral properties. The metal ions carried on the microparticle carriers are gradually released from the inside of the microparticle carriers, and the antibacterial/antiviral properties based on the metal ions are continuously exhibited.

Examples of metal ions having antibacterial and antiviral properties include silver ions (Ag ⁺ ), copper ions (Cu ⁺ , Cu ²⁺ ), gold ions (Au ⁺ ), mercury ions (Hg ²⁺ ), zinc ions ( Zn ²⁺ ), aluminum ions (Al ³⁺ ), nickel ions (Ni ²⁺ ), iron ions (Fe ²⁺ ), cadmium ions (Cd ²⁺ ), cobalt ions (Co ²⁺ ) and lead ions (Pb ^{2 +} ).

In the present disclosure, the coordination number and stability of the functional group (L) in the metal ion affect the dispersibility of fine particles. From the viewpoint of further improving the dispersibility of fine particles, the coordination number of the functional group (L) in the metal ion is preferably 1 or 2. As metal ions satisfying these conditions, or from the viewpoint of fine particle dispersibility, monovalent cations, silver ions (Ag ⁺ ), copper ions (Cu ⁺ ), gold ions (Au ⁺ ) and mercury ions are selected. (Hg ²⁺ ) is preferred. When the coordination number of the functional group (L) in the metal ion exceeds 3, a plurality of fine particles may be crosslinked by coordinate bonds, resulting in aggregation of the fine particles.

Silver ions (Ag ⁺ ) and copper ions (Cu ⁺ ) are preferred because they form stable complexes with ethylenically unsaturated bonds due to the synergistic effect of σ-bonds and π-bonds. In addition, although silver ions may cause a problem of discoloration due to light or heat, such discoloration can be suppressed by forming a complex with an ethylenically unsaturated bond.

The amount of metal ions carried in the antibacterial/antiviral microparticles of the present disclosure is preferably 5% by mass or more and 70% by mass or less, more preferably 10% by mass or more and 60% by mass or less, from the viewpoint of antibacterial/antiviral properties. It is preferably 20% by mass or more and 60% by mass or less. The supported amount is a theoretical value and is a percentage calculated by the following formula.

Here, "mass of microparticle carrier g" and "mass of metal ion g" are theoretical values calculated from each starting material at a yield of 100%, and are not measured values.

FIG. 1 shows one embodiment of the antibacterial/antiviral microparticles of the present disclosure. The antibacterial/antiviral microparticles 10 are coordinated by microparticle carriers 11 having vinyl groups 12 as functional groups (L) on the surface and inside, and vinyl groups 12 present on the surface and inside of the microparticle carriers 11. and silver ions (Ag ⁺ ) 13 as metal ions. The fine particle carrier 11 is a carrier composed of organopolysiloxane 14 .

The antibacterial/antiviral microparticles of the present disclosure are useful as an antibacterial/antiviral additive. The antibacterial/antiviral microparticles of the present disclosure are useful, for example, as particles having antibacterial/antiviral properties in addition to functioning as an antiblocking agent used in sheets or films and as a filler for resins.

[Method for producing antibacterial/antiviral microparticles]
In one embodiment of the method for producing antibacterial/antiviral microparticles of the present disclosure, an alkoxysilane containing an alkoxysilane having a functional group (L) and water are mixed to form a hydrolyzate of the alkoxysilane (hereinafter “silane The step (1) of obtaining the silane hydrolyzate (also referred to as "hydrolyzate") is mixed with the obtained silane hydrolyzate and a compound that is a source of metal ions having antibacterial and antiviral properties, and the functional group (L) Step (2) of forming a complex monomer containing coordinated metal ions, and step (3) of mixing the obtained silane hydrolyzate containing the complex monomer with a base to polycondense the silane hydrolyzate. including.

In another embodiment of the method for producing antibacterial/antiviral microparticles of the present disclosure, the above step (1) is performed by mixing the obtained silane hydrolyzate with a base to polycondense the silane hydrolyzate. and a step (2') of obtaining a microparticle carrier, and a step (3') of mixing the obtained microparticle carrier with a compound serving as a source of metal ions having antibacterial and antiviral properties.

The cross-linking reaction proceeds in two steps. First, the alkoxy groups of the alkoxysilane are hydrolyzed to form silanol groups, and then the silanol groups are condensed to form siloxane bonds. A catalyst is usually used to accelerate the curing.

In addition, the production method of the present disclosure can produce fine particles containing a fine particle carrier having a functional group (L) on the surface and inside, and a metal ion coordinated by at least a part of the functional group (L). The method is not limited.

<Step (1)>
In step (1), an alkoxysilane containing an alkoxysilane having a functional group (L) is mixed with water. Alkoxysilane provides each structural unit in the organopolysiloxane. As the alkoxysilane, in one embodiment, an alkoxysilane capable of forming each structural unit in the average unit formula (1) by hydrolysis and polycondensation reaction is used.

_{Alkoxysilanes forming the structural unit (R 13 SiO 1/2} ⁾ _include compounds represented by R ¹³ Si ^{(OR 2} ₎ , such as methoxydimethylvinylsilane, ethoxydimethylvinylsilane and methoxydimethylphenylsilane. and ethoxydimethylphenylsilane; and methoxytrimethylsilane and ethoxytrimethylsilane.

_{Alkoxysilanes} forming the structural unit (R ¹² SiO _2/2 ) include compounds represented by R ¹² Si _{(OR 2 ) 2 ,} ^such as dimethoxymethylvinylsilane, diethoxymethylvinylsilane and dimethoxybenzyl methylsilane; and dimethoxydimethylsilane, dimethoxydiethylsilane, diethoxydimethylsilane, diethoxydiethylsilane, dipropoxydimethylsilane and dipropoxydiethylsilane.

Examples of alkoxysilanes forming the structural unit (R ¹ SiO _3/2 ) include compounds represented by R ¹ Si(OR ² ) ₃ such as trimethoxyvinylsilane, triethoxyvinylsilane, trimethoxyallylsilane, Ethoxyallylsilane, (3-(meth)acryloyloxypropyl)trimethoxysilane and (3-(meth)acryloyloxypropyl)triethoxysilane; and methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane. Silanes, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane and butyltrimethoxysilane.

Alkoxysilanes forming the structural unit (SiO _4/2 ) include compounds represented by Si(OR ² ) ₄ such as tetramethoxysilane, tetraethoxysilane and tetrapropoxysilane.

In the above alkoxysilane, R ¹ has the same definition as R ¹ in the average unit formula (1), and R ² is an alkyl group. The number of carbon atoms in the alkyl group is preferably 1 or more and 3 or less. An alkoxysilane in which R ¹ is a vinyl group or an allyl group and R ² is a methyl group or an ethyl group is particularly preferred because it facilitates the production of fine particle carriers. Alkoxysilanes having these groups tend to form fine particles by polycondensation.

The amount of water to be mixed with the alkoxysilane is preferably 1 mol or more and 10 mol or less, more preferably 2 mol or more and 4 mol or less, relative to 1 mol of the alkoxysilane, from the viewpoint of favorably advancing the hydrolysis of the alkoxysilane. .

From the viewpoint of promoting hydrolysis of the alkoxysilane, step (1) is preferably carried out in the presence of an acid catalyst. Acid catalysts include, for example, inorganic acids such as hydrogen chloride, sulfuric acid and nitric acid; organic acids such as formic acid, acetic acid, oxalic acid, maleic acid and fumaric acid. The amount of the acid catalyst is preferably 0.0001 mol or more and 0.1 mol or less, more preferably 0.001 mol or more and 0.05 mol or less, relative to 1 mol of alkoxysilane. 1 type(s) or 2 or more types can be used for an acid catalyst.

In one embodiment, in step (1), the alkoxysilane and dilute hydrochloric acid are mixed.

A silane hydrolyzate is obtained by stirring a mixture of alkoxysilane and water. At least part of the silane hydrolyzate has a functional group (L). The stirring time is preferably 1 minute or more and 60 minutes or less. The temperature during stirring is preferably 5° C. or higher and 50° C. or lower, for example normal temperature.

In one embodiment, the silane hydrolyzate is diluted with water to prepare an aqueous solution having a silane hydrolyzate concentration of 1% by mass or more and 10% by mass or less. The particle size of fine particles can be controlled by the amount of water. At this time, a surfactant may be added to the solution in order to control the particle size of the fine particles. Generally, the higher the surfactant concentration, the smaller the particle size of the microparticles. In the aqueous solution, the final concentration of the surfactant is preferably 0.001% by mass or more and 10% by mass or less, more preferably 0.01% by mass or more and 3% by mass or less.

Surfactants include, for example, sodium dodecyl sulfate (SDS), polyoxyethylene (10) octylphenyl ether, polyoxyethylene (20) sorbitan monooleate, and cetyltrimethylammonium bromide (CTAB). Among these, SDS is preferred. 1 type(s) or 2 or more types can be used for surfactant.

<Step (2)>
In step (2), the silane hydrolyzate obtained in step (1) and a compound that serves as a source of metal ions having antibacterial and antiviral properties are mixed to form a complex monomer. In one embodiment, an aqueous solution of silane hydrolyzate and an aqueous solution of metal ions are mixed. The amount of the metal ion added is preferably 0.01 mol or more and 1 mol or less, more preferably 0.1 mol or more and 0.7 mol or less, per 1 mol of the silane hydrolyzate.

By stirring the mixture of the aqueous solution of the silane hydrolyzate and the aqueous solution of the metal ion, the functional group (L) in the silane hydrolyzate having the functional group (L) is coordinated to the metal ion to form a complex monomer. be done. The stirring time is preferably 1 minute or more and 30 minutes or less. The temperature during stirring is preferably 5° C. or higher and 40° C. or lower, for example normal temperature. In one embodiment, the complex formation between the functional group (L) in the silane hydrolyzate and the metal ion (step (2)) and the polycondensation reaction of the silane hydrolyzate (step (3)) are performed simultaneously. You may proceed.

An aqueous solution of metal ions can be obtained, for example, by dissolving in water a metal salt and/or a metal halide, which are compounds that serve as metal ion supply sources. Examples of metal salts and metal halides include silver (I) nitrate, silver (I) sulfate, copper (I) chloride, copper (II) chloride dihydrate, copper (II) sulfate pentahydrate, dicyanogold (I) Potassium Acid, Mercury (II) Thiocyanate, Zinc (II) Chloride, Zinc (II) Sulfate Heptahydrate, Aluminum (III) Chloride Hexahydrate, Nickel (II) Chloride Hexahydrate, Chloride Iron (II) tetrahydrate, cadmium (II) chloride, cobalt (II) chloride and lead (II) chloride. Among these, silver nitrate (I) is preferable from the viewpoint of the dispersibility of the resulting fine particles, antibacterial/antiviral properties, and safety. One or more metal salts and/or metal halides can be used.

<Step (3)>
In step (3), the silane hydrolyzate containing the complex monomer obtained in step (2) and a base are mixed for the purpose of promoting the polycondensation reaction of the silane hydrolyzate. In one embodiment, an aqueous solution of silane hydrolyzate and an aqueous solution of base are mixed.

Examples of bases include nitrogen-containing compounds such as ammonia, methylamine, ethylamine, triethylamine, ethanolamine and triethanolamine; alkali hydroxides such as sodium hydroxide. One or more bases can be used. In the above mixing, it is preferable to use an aqueous solution of a base, such as aqueous ammonia, triethanolamine aqueous solution and sodium hydroxide aqueous solution, preferably aqueous ammonia. The final concentration of the base after the mixing is preferably 0.1M or more and 10M or less, more preferably 0.5M or more and 3M or less. The particle size of fine particles can be controlled by the amount of base.

By stirring the mixture of the aqueous solution of the silane hydrolyzate and the aqueous solution of the base, the polycondensation reaction of the silane hydrolyzate proceeds to obtain fine particles. The stirring time is preferably 1 minute or more and 60 minutes or less. The temperature during stirring is preferably 5° C. or higher and 50° C. or lower, for example normal temperature.

<Step (2')>
In step (2'), the silane hydrolyzate obtained in step (1) is mixed with a base to polycondense the silane hydrolyzate to obtain a fine particle carrier. In one embodiment, an aqueous solution of silane hydrolyzate and an aqueous solution of base are mixed.

Specific examples of bases and aqueous solutions of bases are as described above. The final concentration of the base after the mixing is preferably 0.1M or more and 10M or less, more preferably 0.5M or more and 3M or less.

By stirring the mixture of the aqueous solution of the silane hydrolyzate and the aqueous solution of the base, the polycondensation reaction of the silane hydrolyzate proceeds to obtain fine particle carriers. The stirring time is preferably 1 minute or more and 60 minutes or less. The temperature during stirring is preferably 5° C. or higher and 50° C. or lower, for example normal temperature.

<Step (3')>
In step (3′), the microparticle carrier obtained in step (2′) is mixed with a compound serving as a source of metal ions having antibacterial and antiviral properties to obtain microparticles. In one embodiment, an aqueous dispersion of particulate carriers and an aqueous solution of metal ions are mixed. The amount of the metal ion added is preferably 0.01 mol or more and 1 mol or less, more preferably 0.1 mol or more and 0.7 mol or less, relative to 1 mol of the functional group (L).

By stirring a mixture of an aqueous dispersion of fine particle carriers and an aqueous solution of metal ions, the functional group (L) in the fine particle carriers is coordinated with the metal ions to obtain the antibacterial/antiviral fine particles of the present disclosure. Here, it is believed that the metal ion forms a complex with the functional group (L) by penetrating into the inside of the fine particle carrier. The stirring time is preferably 1 minute or more and 30 minutes or less. The temperature during stirring is preferably 5° C. or higher and 40° C. or lower, for example normal temperature.

Specific examples of metal salts and metal halides are as described above.

<Other processes>
In the method for producing antibacterial/antiviral microparticles of the present disclosure, the microparticle carriers or antibacterial/antiviral microparticles obtained as described above are treated with at least a portion of R ¹ being a monovalent ethylenically unsaturated group, an aryl group, or A step of treating with the alkoxysilane, which is a group containing a functional group (L) such as an aralkyl group, may be further included. In particular, when the microparticle carrier obtained as described above does not have a functional group (L), the functional group (L) can be introduced later by this step.

The method for producing antibacterial/antiviral microparticles of the present disclosure may further include a purification step. Examples of the purification method include a centrifugal sedimentation method, a purification method using an ion exchange resin, and a dialysis method, and the centrifugal sedimentation method is preferable from the viewpoint of convenience.

[Antibacterial/antiviral composition]
The antibacterial/antiviral composition of the present disclosure contains one or more of the antibacterial/antiviral microparticles of the present disclosure. The compositions of the present disclosure are used in antibacterial and/or antiviral applications.

The antibacterial/antiviral composition of the present disclosure, in one embodiment, contains at least one selected from the group consisting of water and organic solvents. For example, the antibacterial/antiviral microparticles are dispersed in at least one selected from the group consisting of water and organic solvents. Examples of the organic solvent include the specific examples described above.

Examples of methods for dispersing the antibacterial/antiviral fine particles in water or an organic solvent include methods using a magnetic stirrer, a motor with stirring blades, a homogenizer, or an ultrasonic cleaner.

In one embodiment, the antibacterial/antiviral composition of the present disclosure contains one or more resins. For example, antibacterial/antiviral fine particles are dispersed in a resin (matrix resin). Since the antibacterial/antiviral microparticles are excellent in dispersibility in the resin, the transparency of the resin can be maintained.

Examples of resins include polyolefins such as polyethylene, polypropylene and cyclic polyolefins; polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate; styrenes such as acrylonitrile-styrene copolymers, acrylonitrile-butadiene-styrene copolymers and polystyrene; system resin; polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyacrylonitrile, polyamide, polyimide, polyamide-imide, (meth)acrylic resin, (meth)acrylic photocurable resin, polycarbonate, Polyarylphthalate, polysulfone, polyethersulfone, polyphenylene sulfide, polyurethane, acetal resin, cellulose resin, fluororesin, phenolic resin, melamine resin, epoxy resin, unsaturated polyester resin and silicone resin.

The antibacterial/antiviral fine particles and the resin can be mixed using a known mixing device such as a Henschel mixer, a V-type blender, a tumbler, a roll and a kneader.

The content ratio of the antibacterial/antiviral fine particles in the antibacterial/antiviral composition can be arbitrarily selected according to the use of the composition, and in one embodiment, it is 0.01% by mass or more and 70% by mass or less, preferably 0% by mass. .1 mass % or more and 50 mass % or less, more preferably 0.1 mass % or more and 5 mass % or less.

The content of the dispersion medium in the antibacterial/antiviral composition can be arbitrarily selected according to the application of the composition. % by mass or less, more preferably 60% by mass or more and 98% by mass or less. The dispersion medium is, for example, water or an organic solvent.

In one embodiment, the antibacterial/antiviral fine particles of the present disclosure are 0.1 parts by mass or more and 50 parts by mass or less, preferably 0.5 parts by mass or more and 40 parts by mass or less, more preferably 100 parts by mass of the resin. It can be used in an amount of 1 part by mass or more and 30 parts by mass or less.

The antibacterial/antiviral composition of the present disclosure may optionally contain one or more other antibacterial/antiviral ingredients such as sodium hypochlorite and quaternary ammonium salts. The antibacterial/antiviral composition of the present disclosure is optionally selected from the group consisting of polymerizable monomers, polymerization initiators, dispersion stabilizers, moisturizers, thickeners, pH adjusters and surfactants. At least one may be included.

The antibacterial/antiviral composition of the present disclosure can be used to form various shaped bodies such as pellets, sheets, films, plates, containers and pipes. The antibacterial/antiviral compositions of the present disclosure may be applied to substrate surfaces like paints and coatings.

[Antibacterial and antiviral goods]
The antibacterial/antiviral article of the present disclosure has antibacterial and/or antiviral properties and is used for at least one of antibacterial and antiviral applications.

The antibacterial/antiviral article of the present disclosure is not particularly limited as long as it contains the antibacterial/antiviral composition of the present disclosure. The article is formed from the antimicrobial/antiviral composition of the present disclosure or comprises a component (eg, surface, member or part) formed from the antimicrobial/antiviral composition of the present disclosure. In one embodiment, the antibacterial/antiviral article of the present disclosure comprises a layer formed from the antibacterial/antiviral composition of the present disclosure, and the layer is the surface layer of the antibacterial/antiviral article of the present disclosure. constitutes at least part of Since the antibacterial/antiviral article of the present disclosure is excellent in antibacterial and/or antiviral properties, it can be widely used, for example, as an article that comes into contact with human hands.

In one embodiment, the thickness of the layer formed from the antibacterial/antiviral composition of the present disclosure is 0.05 μm or more and 200 μm or less, preferably 0.1 μm or more and 10 μm or less, more preferably 0.15 μm or more and 5 μm or less. be.

In the present disclosure, antibacterial properties of articles are evaluated according to ISO 22196 (JIS Z 2801), and antiviral properties of articles are evaluated according to ISO 21702.

Examples of the above-mentioned articles include film products for protecting touch panels, face shields, handrails, buttons, switches and windows; textile products such as socks, underwear, towels, curtains and carpets; flooring materials, wallpaper, tiles and paint kitchen utensils such as sponges, cutting boards, film packaging materials, brushes and lunch boxes; bath and toilet utensils such as bath mats, brushes with toilet cases and bottles; daily life such as toothbrushes, shoe insoles, masks and antibacterial sprays goods; toys such as stuffed animals and building blocks; household appliances such as washing machines, vacuum cleaners and refrigerators;

The present disclosure relates to, for example, the following [1] to [11].
[1] Microparticle carriers having nonionic functional groups capable of coordinating metal ions on the surface and inside, and antibacterial and antibacterial and/or antiviral microparticles containing either or both antiviral metal ions.
[2] The microparticles according to [1] above, wherein the microparticle carrier is composed of an organopolysiloxane having a group containing a nonionic functional group.
[3] The microparticles according to [1] or [2] above, wherein the nonionic functional group is an ethylenically unsaturated bond.
[4] The microparticles according to [2] above, wherein the group containing a nonionic functional group is at least one selected from the group consisting of a vinyl group and an allyl group.
[5] The microparticles according to any one of [1] to [4] above, wherein the coordination number of the nonionic functional group in the metal ion is 1 or 2.
[6] The microparticles according to any one of [1] to [5] above, wherein the metal ion is a monovalent cation.
[ ^{7 ]} The ^{above [} 1] The microparticles according to any one of [5].
[8] The microparticles according to any one of [1] to [7] above, wherein the amount of metal ions supported on the microparticles is 10% by mass or more and 70% by mass or less.
[9] The microparticles according to any one of [1] to [8] above, wherein the average primary particle diameter of the microparticles is 10 nm or more and 500 nm or less.
[10] An antibacterial and/or antiviral composition comprising the microparticles according to any one of [1] to [9] above.
[11] An antibacterial and/or antiviral article comprising the composition according to [10] above.

The antibacterial/antiviral microparticles of the present disclosure will be described below using specific examples, but the antibacterial/antiviral microparticles of the present disclosure are not limited to the examples.

[Example 1]
2 g of triethoxyvinylsilane and 0.6 mL of 0.1 M diluted hydrochloric acid were mixed and stirred for 30 minutes to obtain a silane hydrolyzate. 24 mL of pure water (H ₂ O), 6 mL of 10% by mass SDS aqueous solution (SDSaq), 2 mL of 1M silver nitrate aqueous solution (AgNO ₃ aq), and 2 mL of 15 M aqueous ammonia (NH ₃ aq) were sequentially added. After 5 minutes, an aqueous dispersion containing microparticles was obtained. The amount (theoretical value) of silver ions supported on the fine particles was 20% by mass.

[Dispersibility evaluation]
The dispersibility of the fine particles obtained in Example 1 in propylene glycol monomethyl ether (PGME), methyl isobutyl ketone (MIBK) and methyl ethyl ketone (MEK) was evaluated as follows.

Using a centrifuge, the microparticles in the aqueous dispersion obtained in Example 1 are allowed to settle, and the supernatant is discarded. redispersed in the This washing operation was repeated one more time.

Finally, 10 mL of PGME was added to the microparticles, and the microparticles were redispersed in PGME in an amount of 1% by weight by sonication. A scanning electron microscope (SEM; "SU-8000" manufactured by Hitachi High-Technologies Corporation) image of the obtained fine particles is shown in FIG. According to the SEM image of FIG. 2, the particle diameter of the fine particles obtained was in the range of 50 nm or more and 90 nm or less, and the average primary particle diameter was 77 nm. Similar operations were performed using MIBK and MEK, respectively. The microparticles obtained dispersed very well not only in PGME, but also in MIBK and MEK.

When the obtained fine particles were subjected to SEM-EDX (elemental analysis; "SU-8000" manufactured by Hitachi High-Technologies Corporation), silver (Ag) was detected (Fig. 3). It was confirmed that silver ions (Ag ⁺ ) were supported on the substrate.

As is clear from the above production process, the vinyl group of the silane hydrolyzate is coordinated with silver ions to form a complex monomer, and the complex monomer polycondenses to form fine particles. Therefore, it can be said that the fine particles obtained have fine particle carriers having vinyl groups as functional groups (L) on the inside and on the surface, and silver ions coordinated by the vinyl groups.

[Antibacterial test]
The microparticles obtained in Example 1 were added to a polyoxyethylene (10) octylphenyl ether aqueous solution having a concentration of 0.05% by mass to obtain 10 mL of a specimen having a concentration of microparticles of 0.01% by mass. When an antibacterial test was conducted according to the following method, a long-lasting antibacterial effect was observed (Table 1).

The antibacterial properties of microparticles (aqueous dispersion) were evaluated according to the following procedure.
First, Escherichia coli (NBRC 3972) used for the test was enriched and cultured in a liquid medium at 35°C for 24 hours. After culturing, the E. coli concentration was adjusted to 10 ⁸ cfu/mL (cfu: colony forming unit) using sterilized normal broth medium (1/500 NB medium). 0.1 mL of this bacterial solution was inoculated into 10 mL of the specimen containing fine particles, and allowed to stand at 25° C. for 1 hour or 24 hours. Thereafter, 10-fold serial dilutions of the specimen were prepared using sterilized phosphate-buffered saline (PBS). 1 mL was taken from each dilution series and mixed with SCDLP agar medium. After culturing this at 30° C. for 48 hours, grown colonies were counted and converted to the number of viable cells. As a negative control, PBS without microparticles (which may contain less than 0.1% by weight of surfactant) was also tested. Finally, the antibacterial activity value was calculated using the following formula (Log is a common logarithm with a base of 10). Antibacterial activity value (24 hours) of 3.0 or more was determined to be effective.

[Examples 2 to 6]
Fine particles were obtained in the same manner as in Example 1, except that the amount of each component used was changed as shown in Table 1. All of the fine particles obtained in Examples 2 to 6 had good dispersibility in PGME, MIBK and MEK. Table 1 shows the evaluation results of the antibacterial test.

[Example 7]
2 g of triethoxyvinylsilane and 0.6 mL of 0.1 M diluted hydrochloric acid were mixed and stirred for 30 minutes to obtain a silane hydrolyzate. Here, 24 mL of pure water, 6 mL of 10% by mass SDS aqueous solution, and 2 mL of 15 M ammonia water were sequentially added. After 5 minutes, an aqueous dispersion containing fine particle carriers having vinyl groups as functional groups (L) was obtained. 2 mL of 1M silver nitrate aqueous solution was added thereto and stirred for 30 minutes. As described above, fine particles in which silver ions were supported on fine particle carriers were obtained. The particle diameter of the obtained fine particles was in the range of 50 nm or more and 90 nm or less, and the average primary particle diameter was 71 nm. The amount (theoretical value) of silver ions supported on the fine particles was 20% by mass. The fine particles obtained in Example 7 had good dispersibility in PGME, MIBK and MEK. An antibacterial activity test was conducted in the same manner as in Example 1, and the antibacterial activity value was 8.2 after 24 hours, indicating an excellent antibacterial effect.

When the fine particles obtained in Example 7 were subjected to SEM-EDX (elemental analysis), silver (Ag) was detected as in Example 1 (Fig. 4). From this result, it was confirmed that silver ions (Ag ⁺ ) were carried on the fine particle carrier. The SEM-EDX spectrum of FIG. 4 shows similar peaks to the SEM-EDX spectrum of FIG. Therefore, it can be said that the fine particles obtained in Example 7 also have fine particle carriers having vinyl groups as functional groups (L) inside and on the surface, and silver ions coordinated by the vinyl groups.

[Comparative Example 1]
Commercially available silver zeolite particles (Sinanen Zeomic Co., Ltd., AJ10N) were obtained, and an MIBK dispersion (particle concentration: 1% by mass) was prepared. When this dispersion liquid was dropped onto a slide glass and observed with an optical microscope, it was observed that particles with a particle diameter of about 2.5 μm were aggregated.

[Comparative Example 2]
2 g of triethoxymethylsilane and 0.6 mL of 0.1 M diluted hydrochloric acid were mixed and stirred for 30 minutes to obtain a silane hydrolyzate. Here, 24 mL of pure water, 6 mL of 10% by mass SDS aqueous solution, and 1 mL of 15 M aqueous ammonia were sequentially added. After 5 minutes, an aqueous dispersion containing fine particles having a particle size in the range of 50 nm to 90 nm was obtained. To this, 3 mL of 10 vol % 3-aminopropyltrimethoxysilane aqueous solution was added. After 5 minutes aminated microparticles were obtained. This was centrifuged, suspended in IPA and then centrifuged again. This was suspended in 40 mL of methanol and sonicated. 0.2 g of succinic anhydride was added thereto and reacted at 60° C. for 1 hour. As a result, a fine particle carrier having a carboxyl group as an ionic functional group capable of coordinating with metal ions was obtained. Although 20 mL of 0.1 M silver nitrate aqueous solution was added thereto, the fine particle carriers gradually aggregated. This is probably because the fine particle carriers having carboxyl groups were crosslinked by silver ions.

[Comparative Example 3]
Fine particles were obtained in the same manner as in Example 2, except that the amount of pure water was changed to 38 mL, the 1 M silver nitrate aqueous solution was changed to 0 mL, and the 15 M ammonia water was changed to 2 mL. The particle diameter of the obtained fine particles was in the range of 35 nm or more and 50 nm or less, and the average primary particle diameter was 41 nm. The fine particles obtained had good dispersibility in PGME, MIBK and MEK. When an antibacterial test was conducted in the same manner as in Example 1, no antibacterial effect was observed (Table 1). This is probably because there was no silver ion forming a complex with the vinyl group contained in the fine particle carrier.

[Comparative Example 4]
Fine particles were obtained in the same manner as in Example 4, except that triethoxymethylsilane was used instead of triethoxyvinylsilane. The particle diameter of the obtained fine particles was in the range of 35 nm or more and 50 nm or less, and the average primary particle diameter was 38 nm. The fine particles obtained had good dispersibility in PGME, MIBK and MEK. When an antibacterial test was conducted in the same manner as in Example 1, no antibacterial effect was observed (Table 1). This is probably because the methyl group contained in the fine particle carrier did not form a complex with the silver ion.
In Table 1, examples in which the antibacterial activity value (1 hour) column is hatched mean that the antibacterial activity value has not been measured.

[Example 8]
An ink containing the microparticles (MIBK dispersion) obtained in Example 1 was coated onto a polyethylene terephthalate (PET) film as follows.

First, an ink having the following composition was prepared.
Solvent: MIBK 5.046g
Antibacterial component: MIBK dispersion of microparticles obtained in Example 1 (concentration of microparticles: 2% by mass)
0.789g
UV curable resin: KRM8713B (Daicel Allnex) 0.157 g
Polymerization initiator: Omnirad 184 (BASF) 0.006 g

The above ink was applied to a PET film (Cosmo Shine A4100, Toyobo), dried, and then irradiated with ultraviolet rays. As a result, a cured film (thickness of about 200 nm) containing fine particles was formed on the surface of the PET film.

The antibacterial properties of the cured film obtained as described above were evaluated according to ISO 22196 (JIS Z 2801). As a result, the antibacterial activity value was 6.2, indicating an excellent antibacterial effect against Escherichia coli (NBRC 3972). The negative control was the PET film not coated with the ink.

10 Antibacterial/antiviral microparticles 11 Microparticle carriers 12 Functional groups (L)
13 ... Metal ion having antibacterial and antiviral properties 14 ... Organopolysiloxane

Claims (11)

a fine particle carrier having, on its surface and inside, nonionic functional groups capable of coordinating with metal ions;
For antibacterial and/or antiviral use, comprising metal ions having either or both antibacterial and antiviral properties coordinated by the nonionic functional groups present on the surface and inside of the microparticle carrier. Fine particles. The fine particle carrier is
2. The microparticles according to claim 1, which are carriers composed of organopolysiloxane having groups containing nonionic functional groups. 3. Microparticles according to claim 1 or 2, wherein the nonionic functional group is an ethylenically unsaturated bond. 3. The microparticles according to claim 2, wherein the group containing the nonionic functional group is at least one selected from the group consisting of vinyl groups and allyl groups. The fine particle according to any one of claims 1 to 4, wherein the coordination number of the nonionic functional group in the metal ion is 1 or 2. Microparticles according to any one of claims 1 to 5, wherein the metal ions are monovalent cations. Claims 1 to 3, wherein the metal ion is at least one selected from the group consisting of silver ions (Ag ⁺ ), copper ions (Cu ⁺ ), gold ions (Au ⁺ ) and mercury ions (Hg ²⁺ ). 6. Microparticles according to any one of 5. The microparticles according to any one of claims 1 to 7, wherein the amount of metal ions supported on the microparticles is 10% by mass or more and 70% by mass or less. The microparticles according to any one of claims 1 to 8, wherein the microparticles have an average primary particle diameter of 10 nm or more and 500 nm or less. An antibacterial and/or antiviral composition comprising the microparticles according to any one of claims 1-9. An antimicrobial and/or antiviral article comprising the composition of claim 10.

Images