JPS6045643B2 - Method for manufacturing antibacterial materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an antibacterial material in which silver ions as antibacterial metal ions are ionically bonded to particles, fibers, or various molded articles made of a polymeric substance.

It has been well known for a long time that silver ions exhibit excellent antibacterial properties, and these antibacterial metal ions are widely used in various fields as bactericidal or disinfectant agents in the form of salts such as silver nitrate.

However, although this antibacterial agent has strong antibacterial activity, it is difficult to handle because it is in the form of a solution, and its uses are limited. This invention enables the antibacterial ions to react with a solid material made of a specific polymer having a functional group, and fixes the antibacterial ions with the functional groups, thereby producing emulsions, cypendions, pastes, and powders. , can be used in individual forms such as granules, sheets, films, etc., or supported on carriers such as woven fabrics and plastic films, expanding its uses, and has sustained release properties with excellent long-term sustainability. There are some attempts to provide antibacterial materials.

That is, the present invention provides particles, fibers or porous materials comprising a sulfone group-containing (meth)acrylic acid alkyl ester polymer having a sulfone group content of 0.008 to 2.4 milliequivalents per polymer. By treating molded products such as coagulated products, films, and sheets with an aqueous solution of silver nitrate, 0 silver ions as antibacterial metal ions are added to the sulfone groups contained in the particles, fibers, or molded products per 1 Da of the polymer. This invention relates to a method for producing an antibacterial material, characterized in that the ionic bonding is carried out at a ratio of 0.0009 to 0.9 mmol.

In this invention, a (meth)acrylic acid alkyl ester polymer containing a sulfonic group is obtained.

To obtain this polymer, for example, one or more monomers containing a sulfonic group, an alkyl (meth)acrylic acid ester monomer, and, if necessary, other monomers copolymerizable with these are combined by emulsion polymerization, solution polymerization, or bulk polymerization. Copolymerization may be carried out according to a conventional polymerization method such as. In the case of emulsion polymerization, many sulfone groups are distributed on the particle surface, which has the advantage that reaction with silver ions can be carried out favorably, and is therefore particularly preferred. Examples of the monomer containing the sulfonic group include styrene sulfonic acid, allyl sulfonic acid, sulfopropyl acrylate, sulfopropyl methacrylate, 3-chloro-4-vinylbenzenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2- Examples include acryloyloxybenzenesulfonic acid, 2-acryloyloxynaphthalene-2-sulfonic acid, 2-metharyloyloxynaphthalene-2-sulfonic acid, 2-hydroxy-3-sulfopropyl methacrylate, and their potassium, sodium, and ammonium salts. .

Further, the above-mentioned copolymerizable monomers can be selected from a wide range depending on the use of the antibacterial material, but specific examples include vinyl chloride, vinylidene chloride, vinyl acetate, styrene and its derivatives, Examples include butadiene, acrylamide and its derivatives, allyl compounds such as allylpropyl ether, vinyl ether, acrylonitrile, methacrylonitrile, and glycidyl methacrylate.

In addition to the above, the sulfonic group-containing (meth)acrylic acid alkyl ester polymer can be produced by using, for example, a (meth)acrylic acid alkyl ester monomer and another monomer copolymerizable with it, instead of using a sulfonic group-containing monomer. After copolymerizing and forming this polymer into a porous coagulate as necessary, this is treated with sodium bisulfite, concentrated sulfuric acid, chlorosulfonic acid, etc. to introduce sulfone groups into the copolymer molecules. It can also be obtained by this method.

Sulfonic group-containing (meth) obtained by these methods
The sulfone group content in the acrylic acid alkyl ester polymer is from 0.008 to 1 Da per polymer.
2.4 milliequivalents, preferably 0.08 to 0.8 milliequivalents.

In this invention, the polymer is then treated with an aqueous solution of silver nitrate, and this treatment is carried out while the polymer is in the form of a solid material such as particulates, fibers, porous coagulates, films, sheets, etc. conduct.

By doing so, silver ions as antibacterial metal ions are introduced mainly onto the surface of each solid substance through ionic bonding, so that antibacterial performance can be better exhibited. In addition, when the sulfonic group-containing (meth)acrylic acid alkyl ester polymer is obtained by the above-mentioned emulsion polymerization, etc., this is used as emulsion particles,
In other words, since it is in the form of particulate matter, it is better to treat it directly with an aqueous silver nitrate solution. Molded articles such as fibers, porous coagulates, films, and sheets are prepared in various forms from the above-mentioned particulate matter or from the above-mentioned polymer solution in a conventional manner, and then treated with an aqueous silver nitrate solution. In addition,
It goes without saying that various additives can be added depending on the purpose of use when producing the above-mentioned molded product. After treatment with an aqueous silver nitrate solution, excess silver ions are washed away and dried to obtain an antibacterial material in which silver ions are ionically bonded primarily to the surface of particles, fibers, or molded objects. .

When this material is in the form of particles, it can be used as an emulsion or suspension, as a powder or granules, in the form of various molded products, or as supported on a carrier. Molded products such as fibers, porous coagulates, films, and sheets can be used as they are, or after being further molded or supported on a carrier. The content of silver ions as antibacterial gold ions in these antibacterial materials in various forms is 0.0009 to 0.9 mmol, preferably 0.0045 to 0.45 mmol per 1y of polymer.

Next, in order to show how excellent the antibacterial material obtained by the method of the present invention is, the following test results using the antibacterial film obtained in Example 1 described later will be detailed. .

I Detailed antibacterial property: Antibacterial cathes by disc method
Test bacteria: Bacillus subtilis
Staphylococcus aureus (Sta.
PhylOCOCCllSaureus) Escherichia coli (Escherichia coli)
Oll) Pseudomonas aeruginosa
(PseudOmOnasaeruginOsa)
Candida albicans
aalbicans) Aspergillus niger
(Aspergillusni?r)
Chaetmium glabosum
OmiumglabOsunl) Cladosporium reginae (CladOspOriu
mresinae) Penicillium citrinum
) Trichoderma SP. (TrjchOderm
asp. ) Among the above test bacteria, for bacteria, 1 Cf'~1 (73 bacterial cells were dispersed and plated on a Nikko scratch agar medium, a test film was placed on top of the plate, and after culturing at 37°C overnight, the inhibition zone was The presence or absence of formation was observed.

On the other hand, for fungi, using a potato sucrose agar medium, approximately 1 Cf' of spores were dispersed in the medium to form a flat plate, a test film was placed on top of the plate, and after culturing at 30°C for one week, the presence or absence of masticulate band formation was determined. Observed.

The results of the above tests are shown in Table 1.

0: Inhibition zone formed ■ Killing rate of bacteria on the film Aspergillus flavus (Aapergillus flavus)
lavus) spore suspension (4). 0.1 ml (10i to 1σ pieces) of 0.05% sodium dodecylbenzenesulfonate was placed on each test film and stored at 30°C.

After a certain period of time, it was sampled, diluted, dispersed in SabOura medium, and plated. After cultivating this in a medium between two plates at 30'C, the number of surviving individuals was measured and the mortality rate was determined.
It was found that 99% mortality had occurred after 24VI1 period. ■
Sustainability of antibacterial activity Using Cladosporium resirlae as the test bacterium, a 5cm x 5cm test film was washed repeatedly with 5e of water each time, and the sustainability was determined by the number of washings until the antibacterial activity was lost. was evaluated.

The results are shown in Table 2. For comparison, a similar test was also conducted on an antibacterial film according to a comparative example described later in which antibacterial metal ions were simply blended without being fixed with a sulfone group.

The results are also listed in Table 2. As is clear from the above results, the antibacterial material according to the present invention exhibits excellent antibacterial properties against both bacteria and fungi, has a large ability to kill bacteria on the film, and has antibacterial activity. It also has excellent durability. As can be understood from what has already been described, the antibacterial material of the present invention having such effects can be applied to emulsions, suspensions, powders, granules, sheets or films, porous solids (including porous films). ), other molded articles, fibers, etc., or in the form of non-woven fabrics, foamed cynotes, paper, etc.
It can also be used in combination with carriers such as plastic films and inorganic plates, and can be used in various applications that take advantage of this advantage, such as various coating compositions such as marine paints and architectural wall paints, perforation materials, and ionizing materials. Can be widely used for replacement materials, dialysis membranes, valve slurry and slime prevention additives, packaging materials, air filters, wallpaper, hospital pet covers, sheets, sterile clothing, and underlay sheets for dressers, closets, cupboards, etc. can.

Next, the present invention will be explained in more detail with reference to Examples.

In addition, in the following examples, parts and % mean parts by weight and % by weight, respectively. Example 1 Monomer mixture 1 (1
) part of an aqueous solution containing 0.5% of ammonium persulfate and 5% of an emulsifier (manufactured by Neugen EAl6 Dai-ichi Kogyo Seiyaku Co., Ltd.).
5 (2) and heated to 70°C while stirring in a nitrogen atmosphere.
Polymerization was started at about 75° C. for 5 hours to complete the polymerization.

Next, some coagulated matter contained in the emulsion was removed by filtration to obtain an emulsion with a substantially uniform particle size.
The emulsion had a nonvolatile solids content of 40% and an average particle size of 0.10 microns.

The content of sulfone groups in the polymer was 0.22 equivalent per 1y of polymer. After this emulsion was cast onto a glass plate, it was immediately immersed in a medium prepared by dissolving 5% hydrochloric acid (water: methyl ethyl ketone 7:3) for about 5 minutes, resulting in porous solidification in which some of the particles were fused. Make it a thing. This coagulated material was immersed in pure water to replace the absorbed medium with water until it reached an equilibrium state, and then the coagulated material was peeled off from the glass plate, washed with water, and dried. 5% of the obtained porous coagulum
After being immersed in an AgNO3 aqueous solution for two days, the film was thoroughly washed with water and dried to obtain an antibacterial porous film in which Ag ions were fixed to the sulfone groups.

The content of Ag+ ions was 0.14 mmol per y of polymer. Antibacterial test results regarding this film are already available. In addition, to evaluate sustainability, we separately investigated the period of time until antibacterial activity was no longer observed after immersing in boiling water using the disk method, and the results showed that it lasted more than 6 months. However, the test bacterium used at this time was Etsuchierihiacoli. This kind of porosity. The sterile film can be used as it is or reinforced with non-woven fabric for use as a filter material for sterile water, air filters, etc. Example 2 Styrene 50%, ethyl acrylate 40%, 2-a4acrylamido-2-methylpropanesulfonic acid sorter 10
% was emulsion polymerized in the same manner as in Example 1 to obtain an emulsion with an average particle size of 0.09 P1 and a nonvolatile solid content of 45%.

The sulfone group content in the polymer is 0 per y of polymer.
．． The amount was 41 millimeters. This emulsion was cast onto a polyester film and dried at 120° C. for 3 minutes to obtain a uniform film.

The resulting film was immersed in a 5% AgNO3 aqueous solution for three times, thoroughly washed with water, and dried to obtain an antibacterial film in which Ag ions were fixed to the sulfone groups. The content of 8' ions was 0.15 mmol per y of polymer.
Example 3 Methyl methacrylate 30%, ethyl acrylate 60%,
100 parts of a monomer mixture consisting of 10% glycidyl methacrylate was dispersed in 1 part of an aqueous solution containing 5% of an emulsifier (Neugen EAl6O, manufactured by Daiichi No Kogyo Seiyaku Co., Ltd.), and the mixture was dispersed for 40' while stirring in a nitrogen atmosphere. C, polymerization was carried out using hydrogen peroxide-sodium ascorbate as an initiator.

After the polymerization is complete, some coagulated matter contained in the emulsion is removed by overnight filtration, resulting in almost uniform particles. A degree of emulsion was obtained. The resulting emulsion had a non-volatile solids content of 46%.
The average particle size was 0.15p.

This emulsion was made into a porous coagulate in the same manner as in Example 1. This porous coagulum was immersed in a 5% aqueous sodium bisulfite solution, treated at 60'C for 5 hours, and further reacted at 80°C for 2 hours.

As a result, a sulfone group was introduced into the glycidyl group. The amount of sulfone group introduced was 0.2 meq/da. After thoroughly washing this film with water, it was immersed in a 5% AgNO3 aqueous solution for 30 minutes, thoroughly washed with water, and then dried to obtain an antibacterial porous film in which Ag+ ions were fixed to the sulfone groups. A
The content of g+ ions was 0.11 mmol per y of polymer. Comparative Example A monomer mixture consisting of 50% styrene, 49% ethyl acrylate, and 1% divinylbenzene was emulsion polymerized in the same manner as in Example 1 to obtain an emulsion with an average particle size of 0.22p and a nonvolatile solid content of 44%. Obtained.

After adding 4 parts of 10% AgNO3 aqueous solution to 1 (4) parts of this emulsion, it was cast onto a polyester film,
A uniform film was obtained by drying at 145°C for 3 minutes. The obtained film is simply a blend of antibacterial agents, and as stated in the text, the results of testing the durability of antibacterial activity on this film showed that the antibacterial activity disappears relatively easily by washing with water. I found out.

Claims (1)

[Claims] 1 Sulfone group content is 0.008 to 1 g of polymer
Particles made of a (meth)acrylic acid alkyl ester polymer having a sulfonic group content of 2.4 milliequivalents,
By treating molded products such as fibers or porous coagulates, films, and sheets with an aqueous solution of silver nitrate, 1 g of the above polymer is added to the sulfone groups contained in the particles, fibers, or molded products as antibacterial metal ions. Per 0.
A method for producing an antibacterial material, characterized in that the ionic bonding is carried out at a ratio of 0009 to 0.9 mmol.