JP2002003239A - Glass based antibacterial agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antibacterial agent composed of glass, which exhibits an excellent antibacterial property by compounding it with a resin and is also excellent in discoloration resistance, water resistance, and external appearances. SOLUTION: The agent is composed of glass which contains 54-60 mol% ZnO, 25-32 mol% B2O3, 7-12 mol% SiO2, and 5-8 mol% an alkali metal oxide, based on the total amount of components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass-based inorganic antibacterial agent containing zinc oxide at a high concentration and an antibacterial resin molded article comprising the antibacterial agent and a resin. Inorganic antibacterial agents are resins,
It is kneaded during the molding of synthetic fibers and is used to kill or suppress the growth of bacteria attached to the surface of plastic molded products and textile products, or dispersed in coating materials to produce plastic molded products, textile products, It is applied to various molded products such as wood products, paper products, ceramic products and the like, and is used for the purpose of imparting antibacterial properties, as well as fungicidal properties and anti-algal properties to the surface thereof. The inorganic antibacterial agent of the present invention is useful for producing these antibacterial, antifungal and antialgal products.

[0002]

2. Description of the Related Art Conventionally, as an inorganic antibacterial agent, an antibacterial metal such as silver or copper supported on apatite, zeolite, glass, zirconium phosphate, silica gel or the like is known. These are highly safe compared to organic antibacterial agents, are hardly eluted, do not volatilize or decompose, have a long lasting antibacterial effect, and have excellent heat resistance. Therefore, by mixing these antibacterial agents with various polymer compounds, they are widely used in the production of antibacterial resin products such as fibers, films or various molded articles.

[0003] Above all, a glass-based antibacterial agent containing an antibacterial metal such as silver, copper or zinc in glass is easy to adjust the particle size, and the refractive index and the antibacterial property are changed by variously changing the composition of the glass component. It has the characteristic that the dissolution rate of the reactive metal can be easily controlled according to the purpose.

Japanese Patent Publication No. 74453/1992 discloses an antibacterial agent comprising a glass containing silver, Japanese Patent Application Laid-Open No. 2-307968 discloses an antibacterial agent comprising a glass containing silver or copper, and an antibacterial agent comprising a glass containing zinc. Japanese Patent Application Laid-Open No. 7-257938 proposes various inventions. However, antibacterial agents made of conventional silver-containing glass,
Despite the high antibacterial effect, the resin processed product may be discolored or deteriorate due to the effects of heat applied when kneading the resin or UV exposure after molding, etc. There was a problem.

[0005] Further, the antibacterial agent made of copper-containing glass is colored blue, and the resin molded product obtained by kneading the same also turns blue, so that it is difficult to use it for white and light-colored products. However, there is a problem that the range of use is limited, for example, in products of colors other than the above, such as hindrance to color matching. Furthermore, an antibacterial agent consisting of glass containing copper or zinc,
Because antibacterial properties are low compared to silver-containing glass, when trying to sufficiently exhibit antibacterial effects in the resin composition,
There is a problem that the amount added to the resin must be increased, and the original resin physical properties are deteriorated.

In order to solve these problems, P ₂ O ₅
40-55 mol%, ZnO 35-45 mol%, Al
The ₂ O ₃ 5 to 15 _mol%, the B 2 _{O 3} with respect to 100 parts by weight of glass containing 1 to 10 mol%, 0.01 for Ag ₂ O
An antibacterial agent containing 1.0% by weight has been proposed (JP-A-8-175843). However, the amount of Ag ₂ O added to enhance the antibacterial performance of this antibacterial agent is limited in order to suppress discoloration due to silver ions, so that the antibacterial property is just one step away. Further, the glass used here has a high elution rate of the antibacterial metal (Zn), and although the initial antibacterial property is high, the persistence of the antibacterial effect is not sufficient.

Japanese Patent Application Laid-Open No. 11-29343 discloses a ZnO—B ₂ O ₃ —SiO ₂ system (ZnO 25-80).
_{Mol%, B} 2 O 3 _{5~50 mol%,} SiO 2 1 to 7
0 mol%, and the total of these three components in Examples 1 to 9 is 72.5 to 100 mol%. ), And an antibacterial glass powder having a Na ₂ O content of 4 mol% or less has been proposed. Na ₂ O content of 4 mol%
The following is intended to improve the appearance of the resin product mixed with the glass powder, that is, the roughness of the resin product and the decrease in gloss over time. On the other hand, it contains only a very small amount of an alkali metal ion which is a glass network modifying component having a low binding force, so that the solubility of the glass is low and the antibacterial property is not sufficient. .

[0008]

DISCLOSURE OF THE INVENTION The present invention provides excellent antibacterial properties when blended with a resin, and also has resistance to discoloration, water resistance,
An object of the present invention is to provide an antibacterial agent made of glass excellent in appearance.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, they have found that ZnO is contained at a very high concentration and SiO ₂ , B ₂ O ₃ and alkali metal oxides are contained. The silicate glass containing a specific concentration of the substance has a high antibacterial property, and is also an excellent antibacterial agent that is excellent in discoloration resistance and water resistance, which are concerned, and solves all the above-described problems. The present invention has been completed.
That is, in the present invention, ZnO is added in an amount of 54 to 60 mol% and B ₂ O ₃
The 25 to 32 mol%, the SiO ₂ 7 to 12 mol%, an antibacterial agent consisting of glasses containing 5-8 mol% of alkali metal oxides. Hereinafter, the above glass in the present invention is referred to as an antibacterial glass.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. ○ Antibacterial glass The antibacterial glass of the present invention contains ZnO in an amount of
The ₂ O ₃ 25 to 32 mol%, the SiO ₂ 7 to 12 mol%, a glass containing 5-8 mol% of alkali metal oxides. It is generally known that the oxide component contained in glass is divided into a component forming a glass network serving as a framework, a network modifying component located in a gap between the components, and an intermediate component between the two. In the antibacterial glass of the present invention, B ₂ 0 ₃ and SiO ₂ is a glass network forming component acts to keep the predominantly stable glass framework, ZnO is an intermediate component, mainly contributes to the expression of antimicrobial activity, mesh It is considered that the alkali metal oxide as a modifying component facilitates melting and moldability of glass and contributes to adjustment of solubility and the like. The preferred ZnO content is 55 to 58 mol%. A preferable content ratio of B ₂ O ₃ is 26 to 29 mol%.
And the preferable content ratio of SiO ₂ is 8 to 11 mol%.
And a preferable ratio of the alkali metal oxide is 6 to 8 mol%.

[0011] 4 components of _{ZnO, B} 2 O _3, preferably the content of SiO ₂ and alkali metal oxides is not determined for each component, _{ZnO, B} 2 O _3, SiO ₂ and alkali metal oxides Only when the ratio is the above-mentioned specific ratio, the antibacterial property is high, the discoloration resistance and the water resistance are excellent. If the ratio is outside these ranges, the antibacterial activity is insufficient, or the water resistance and discoloration resistance of the resin molded article to which the antibacterial agent is added are reduced.

That is, the content of ZnO in the glass of the present invention is from 54 to 60 mol%, but if it is less than 54 mol%, the antibacterial activity is reduced, and if it exceeds 60 mol%, it is difficult to form a stable glass network. . The content ratio of P ₂ O ₅ is 20 to 3
Although it is 5 mol%, if it is less than 20 mol%, a stable glass network cannot be obtained, and if it exceeds 25 mol%, the water resistance of the glass is impaired. The content ratio of the alkali metal oxide is 5
However, if it is less than 5 mol%, the solubility of the glass becomes too small to exhibit sufficient antibacterial properties,
On the other hand, if it exceeds, the solubility is too large, and the water resistance is impaired.
Preferred examples of the alkali metal contained in the antibacterial glass of the present invention include Li, Na, and K, and Na is particularly preferred.

The glass network forming component contained in the antibacterial glass of the present invention is essentially SiO _2, but other glass network forming components can be partially added as desired. Preferred examples of the glass network forming component other than SiO ₂ include ZrO ₂ , TiO ₂ , P ₂ O ₅ , and Al ₂ O ₃ . In order not to impair the excellent antibacterial properties, water resistance and discoloration resistance, which are features of the present invention, the content of glass network forming components other than SiO ₂ is preferably 5 mol% or less in total.

When compounding the antimicrobial glass of the present invention with a resin,
Usually in the form of powder, those having an average particle diameter of 20 μm or less are generally preferable for dispersion processing into resin, and are preferably used for textile products and paints.
In the case of processing into a film or the like, those having an average particle size of 5 μm or less and a maximum particle size of 20 μm or less are preferable so as not to cause deterioration in physical properties.

The method for producing the antimicrobial glass of the present invention is not limited, and a known production method can be employed. In general, after a raw material mixture of glass is melted at 1000 to 2000 ° C. in a melting pot, the melt is quenched, and the glass is prepared. Obtainable.

The antibacterial glass of the present invention contains a large amount of zinc oxide (melting point: about 2000 ° C.) as compared with conventional glass-based antibacterial agents so as to exhibit remarkably excellent antibacterial properties. Glass having the composition of the present invention can be obtained by selecting an appropriate melting temperature and using quenching means suitable for the cooling characteristics of the melt, although it has a property of not easily forming a skeleton.

In order to enhance the quenching effect, it is effective to increase the contact area between the melt and the cooling body. For example, the melt of glass is sandwiched between two rotating metal rollers cooled by a coolant such as water. Is passed through at a high speed to obtain an extremely large cooling effect. By using this cooling method, vitrification is extremely easy. Further, when cooled by this method, since the glass that has come out between the rollers is formed into a thin plate, it can be very easily crushed into a powder.

When the antibacterial glass of the present invention is kneaded into a resin or a fiber, the antibacterial performance is exhibited by an antibacterial agent present on the surface of the resin molded product or the fiber. May fall off. When shedding is remarkable, the antibacterial effect decreases, and in some cases, the effect disappears in a very short time. When kneading the antibacterial glass of the present invention into a resin or the like, to improve the adhesion and adhesion,
In order to prevent the antibacterial glass from falling off, it is preferable to treat the surface of the antibacterial glass itself with a silane coupling agent or the like.

The surface treatment agent used for improving the performance of the antimicrobial glass of the present invention may be appropriately selected depending on the use, the type of resin, the processing method, and the like. Any of those used as coupling agents can be used, and there is no particular limitation. Specific examples of the surface treatment agent include vinyl silanes such as vinyl triethoxy silane and vinyl trimethoxy silane, and (meth) acryloxy silanes such as γ- (methacryloxy propyl) trimethoxy silane and γ-glycidoxy propyl trimethoxy silane. Sidoxysilane, tetraethoxysilane, silicone oil, tetraisopropoxytitanium, aluminum ethylate and the like can be mentioned. The surface treatment method is not particularly limited, and any method conventionally known as a surface treatment method for inorganic powders, for example, a dry method, a wet method, a spray method, a gasification method, or the like can be used.

By blending the antimicrobial glass of the present invention with various resins, an antimicrobial resin composition can be easily obtained. The type of resin that can be used is not limited, and may be any of a natural resin, a synthetic resin, and a semi-synthetic resin, and may be any of a thermoplastic resin and a thermosetting resin. The specific resin may be any of a molding resin, a fiber resin, and a rubber-like resin. Examples thereof include polyethylene, polypropylene, vinyl chloride, ABS resin, AS resin, nylon resin, polyester, polyvinylidene chloride, and polystyrene. , Polyacetal, polycarbonate, PBT,
Acrylic resin, fluororesin, polyurethane elastomer, polyester elastomer, melamine, urea resin, tetrafluoroethylene resin, unsaturated polyester resin,
Polyethylene, polypropylene, rayon, acetate
Resin for molding or fiber such as acrylic, polyvinyl alcohol, cupra, triacetate, vinylidene, natural rubber, silicone rubber, styrene butadiene rubber, ethylene propylene rubber, fluorine rubber, nitrile rubber, chlorosulfonated polyethylene There are rubber-like resins such as rubber, butadiene rubber, synthetic natural rubber, butyl rubber, urethane rubber, and acrylic rubber.

The preferred proportion of the antibacterial glass contained in the antibacterial resin composition is 0.01 to 10 parts, more preferably 0.1 to 5 parts, per 100 parts of the antibacterial resin composition. If the amount is less than 0.01 part, the antibacterial property of the antibacterial resin composition may be insufficient. On the other hand, if the amount is more than 10 parts, the antibacterial effect is hardly further improved. In order to enhance the dispersibility of the antibacterial glass during molding, a masterbatch in which the antibacterial glass is pre-mixed with a resin so that the concentration of the antibacterial glass is higher than that in the final product is not poured into the molding machine as it is, It is preferable to prepare an intermediate product, which is referred to as an antibacterial product, by adding this master batch and a straight resin not containing antibacterial glass to a molding machine. In this case, the preferred blending ratio of the antibacterial glass according to the present invention in the master batch is
The amount is 10 to 200 parts by weight, more preferably 10 to 40 parts by weight, per 100 parts by weight of the master batch.

When compounding the antimicrobial glass of the present invention with a resin,
Various additives can be mixed with the resin as necessary in order to improve the kneading processability into the resin and other physical properties. Specific examples of the additives include pigments, dyes, antioxidants, light stabilizers, flame retardants, antistatic agents, foaming agents, impact strengthening agents, glass fibers, metal soaps, moisture inhibitors and extenders, coupling agents, Flow improvers, deodorants, wood flour, antifouling agents,
Rust inhibitors and the like. The antibacterial glass of the present invention can be used alone, but can be used in combination with other inorganic antibacterial agents to further enhance antibacterial properties. In particular, when used in combination with a silver-based inorganic antibacterial agent, the antibacterial effect is remarkably improved due to a synergistic effect of zinc ions in the antibacterial glass of the present invention and silver ions in the silver-based inorganic antibacterial agent.

By using an organic antibacterial / antifungal agent in combination with the antibacterial glass of the present invention, a quick effect of antibacterial performance can be exhibited or the antibacterial / antifungal effect can be improved. Preferred examples of the organic antibacterial antifungal compound used in combination with the antibacterial glass of the present invention include quaternary ammonium salt compounds, fatty acid ester compounds, biguanides, bronopol, phenolic compounds, anilide compounds, iodine. Compounds, imidazole compounds, thiazole compounds, isothiazolone compounds, triazine compounds, nitrile compounds, fluorine compounds, chitosan, tropolone compounds and organometallic compounds (zinc pyrithione,
OBPA).

A known method can be employed for blending the antimicrobial glass of the present invention with a resin. For example, a method of directly mixing a powder of antibacterial glass with an impregnant or a dispersant with a mixer in the form of a pellet or powder with a mixer, and extruding a pellet composition containing the antibacterial glass and the resin by an extruder in advance, A method of mixing the pellet composition with a straight resin containing no antibacterial glass, molding a pellet composition containing wax and a high concentration of antibacterial glass, and then compounding the pellet-shaped product with a straight resin containing no antibacterial glass. And a method in which a paste-like composition obtained by dispersing and mixing an antibacterial glass with a high-viscosity liquid material such as a polyol is blended with a straight resin containing no antibacterial glass.

For molding the compound comprising the antibacterial glass and the resin obtained above, any known processing techniques and machines can be used in accordance with the characteristics of various resins, and the molding is performed by heating at an appropriate temperature. Alternatively, it may be performed by a conventional method while increasing or decreasing the pressure at an appropriate pressure, and the form of the molded article may be various forms such as a lump, a sponge, a film, a sheet, a thread, a pipe, or a composite thereof. It is.

Since the antibacterial resin molded article thus obtained is blended with the antibacterial glass of the present invention having excellent antibacterial properties and resistance to discoloration, it has high antibacterial properties and can be used during molding and after storage. Also, there is no deterioration or discoloration during use.

The use form of the antimicrobial glass of the present invention is not particularly limited. In addition to being used by mixing with the resin as described above, it can be used in the form of powder or granules as it is. Or a composite with other materials, and can be used in various forms such as a liquid dispersion or a paint or an aerosol.

Uses The antibacterial glass of the present invention can be used in various fields where antibacterial, antifungal and antialgal properties are required. Specific applications include, for example, dishwashers, dish dryers, refrigerators, washing machines, pots, TVs, personal computers, CD radio cassettes, cameras, video cameras, water purifiers, rice cookers, vegetable cutters, registers, futon drying Appliances, facsimile, ventilation fan, electric appliances such as air conditioner, tableware, cutting board, push-off,
Trays, chopsticks, old tea utensils, thermos bottles, kitchen knives, ladle handles, fly-backs, lunch boxes, rice scoops, balls, drainers, triangular corners, awaashii, garbage baskets, drainers, and other kitchenware
Shower curtain, futon cotton, air conditioner filter, pantyhose, socks, towel, sheet, futon side lining, pillow, gloves,
Textile products such as aprons, curtains, diapers, bandages, masks, sportswear, decorative boards, wallpapers, floorboards, window films, handles, carpets, mats, artificial marble, handrails,
Home and building material products such as joints, tiles, waxes, toilet seats, bathtubs, tiles, pots, garbage cans, toilet brushes, bath lids, pumice stones, soap containers, bath chairs, clothing baskets, showers, wash basins, and other toiletry products. Paper products such as medicine packing paper, medicine chests, sketchbooks, medical records, origami, dolls, stuffed animals,
Paper clay, blocks, puzzles and other toys, shoes, bags, belts,
Watch bands, interiors, chairs, gloves, leather products such as hanging leather, ball pens, sharp pens, pencils, erasers, crayons, papers, notebooks, floppy disks,
Stationery such as rulers, post-it, stapler, etc., as well as insoles, makeup containers, scourers, makeup puffs, hearing aids,
Musical instruments, cigarette filters, cleaning adhesive paper sheets, hanging leather grips, sponges, kitchen towels, cards, microphones, barber supplies, vending machines, razors, telephones, thermometers, stethoscopes, slippers, costume cases, toothbrushes , Sandbox sand, food packaging films, sprays and other products.

[0029]

The mechanism by which the antibacterial glass of the present invention has excellent antibacterial properties and discoloration resistance is presumed as follows. Z
Since nO-SiO ₂ based glass easily form crystals, it is necessary to add B ₂ O ₃ in order to obtain the stability of the glassy state. Glass _ZnO-B 2 _{O 3} -SiO ₂ system is generally well known and used in the electronic materials and the like. These glasses contain a high concentration of ZnO but do not have sufficient solubility to exhibit antibacterial performance and are not suitable as antibacterial agents. However, since the alkali metal is appropriately added to the antibacterial glass of the present invention, appropriate solubility is generated, and a glass excellent as an antibacterial agent is obtained. That is,
The high concentration of Zn ions contained in the antimicrobial glass of the present invention, due to the presence of a specific amount of alkali metal oxide,
Since it dissolves at an appropriate rate, it has the advantage of high antibacterial properties and high persistence of antibacterial properties. In addition, since it does not contain silver and does not contain an excessive amount of alkali, it is hardly discolored even when it is mixed with a resin at a high temperature and molded, or when a molded product is irradiated with light, and has discoloration resistance. .

[0030]

The present invention will now be described more specifically with reference to examples. ○ Example 1 (Preparation of antibacterial glass) A raw material mixture having the composition (antibacterial glass No. A, B) shown in Table 1 was heated and melted at 1000 to 1400 ° C., and then cooled.
The obtained glass was pulverized with a ball mill to have an average particle size of about 8
A powdered antibacterial agent consisting of μ glass was obtained.

Example 2 5 kg of the antibacterial glass No. A obtained in Example 1 was put into a Hensel mixer, 200 g of an ethanol solution containing 50 g of γ-aminopropyltrimethoxysilane was sprayed with stirring, and then taken out. Surface treatment was performed by heating at 120 ° C. for 12 hours (the treated antibacterial glass is referred to as Sample No. C).

Comparative Example 1 (Preparation of antibacterial glass) In place of antibacterial glass Nos. A and B in Example 1,
Antibacterial glasses DF having the compositions shown in Table 1 were prepared in the same manner as in Example 1.

[0033]

[Table 1]

Test Example 1 Various antibacterial agents (antibacterial glass No. A) prepared in Examples 1, 2 and Comparative Example 1 were added to 100 parts by weight of an isophthalic unsaturated polyester resin blended with fine-particle silica.
To F) were added and mixed in predetermined amounts, respectively, and then a predetermined amount of methyl ethyl ketone peroxide as a curing agent and a predetermined amount of cobalt naphthenate as a curing accelerator were added. 1-6 were obtained. As a comparison, paint composition No. 7 was prepared. The above coating composition was applied to the inside of a mold by a spray gun so as to have a thickness of about 0.5 mm, and was cured at room temperature. Subsequently, an isophthalic acid-based unsaturated polyester base resin composition containing 50% by weight of aluminum hydroxide was poured into a mold, cured at room temperature, and demolded to obtain an artificial marble molded article having a gel coat layer on the surface. The appearance of the molded article was evaluated by visually checking the color of the molded article.

The antibacterial activity of the molded article was evaluated by the following method. 5cm antibacterial artificial marble molding
0.5 ml of a Staphylococcus aureus solution was dropped on the surface of the sample so that the number of bacteria per sample was 105 to 106 pieces. Put a 5cm polyethylene film over the surface and contact it uniformly, temperature 35 ℃, humidity 95RH
% For 24 hours. 0 hours after the start of storage (the number of theoretically added bacteria) and after storage for 24 hours, the surviving bacteria on the sample are washed out in a medium for counting the number of bacteria (SCDLP liquid medium), and the washing solution is mixed using a normal agar medium. The number of viable bacteria was measured by a shaking plate culture method (37 ° C. for 2 days) and converted into the number of viable bacteria per 5 cm × 5 cm of the sample plate. The initial number of bacteria was 2.2 × 105, and the number of bacteria in the control bacterial solution 24 hours after performing the same operation without contacting the sample was 2.5 × 10 5. Further, the appearance of the test piece after being immersed in warm water of 50 ° C. for 500 hours and the antibacterial activity after immersing the test piece in warm water of 90 ° C. for 16 hours were evaluated. Table 2 also shows the results of the above tests.

[0036]

[Table 2]

[0037]

The antibacterial glass of the present invention has excellent antibacterial properties,
It has discoloration resistance and water resistance, and is extremely useful as an antibacterial agent capable of maintaining an antibacterial effect for a long time.
In addition, the antibacterial resin molded article obtained by blending the antibacterial glass of the present invention with a resin has an extremely small appearance deterioration such as discoloration during molding and during long-term storage and use, and exhibits a stable antibacterial effect. Antibacterial product.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 3/40 C08K 3/40 C08L 101/00 C08L 101/00 F-term (Reference) 4F071 AA00 AA09 AA11 AA12 AA12X AA15 AA15X AA20 AA20X AA22 AA22X AA24 AA25 AA26 AA29 AA33 AA34 AA34X AA40 AA41 AA43 AA45 AA47 AA49 AA50 AA53 AA54 AA67 AA77 AA78 AB28 BC01 BC07 4G062 AA10 DC01 EB01 EA01 EA01 EC03 ED01 EE01 EF01 EG01 FA01 FA10 FB01 FC01 FD01 FE01 FF01 FG01 FH01 FJ01 FK01 FL01 GA01 GA10 GB01 GC01 GD01 GE01 HH01 HH03 HH05 HH07 HH09 HH11 HH13 HH15 HH17 HH13 KK01 KK03 JJ01 JJ03 KK03 JJ01 JJ03 KK BC19 DH04 4J002 AA001 AB021 AC011 AC031 AC071 AC081 BB031 BB121 BB151 BB181 BB271 BC031 BC061 BD041 BD101 B D121 BD151 BE021 BG031 BG041 BN151 CB001 CC161 CC181 CF001 CF071 CF101 CF211 CG001 CK021 CL001 CP031 DL006 FD186

Claims (3)

[Claims] 1. ZnO based on the total amount of constituent components
From 54 to 60 mol%, B ₂O_ThreeFrom 25 to 32 mol%, S
iO₂From 7 to 12 mol%, and from 5 to 8 alkali metal oxides.
Antibacterial agent consisting of glass containing mol%. 2. The antibacterial agent comprising glass according to claim 1, wherein the alkali metal constituting the alkali metal oxide is Na. 3. An antibacterial resin molded product comprising the antibacterial agent according to claim 1 and a resin.