JP3325381B2 - Production method of antibacterial zeolite with little discoloration action - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an antibacterial zeolite having a small action of discoloring an organic polymer containing the antibacterial zeolite when the polymer is exposed to heat or sunlight.

[0002]

2. Description of the Related Art It has long been known that silver ions, copper ions, zinc ions and the like have antibacterial properties. For example, silver ions have been widely used as disinfectants and antibacterial agents in the form of silver nitrate solutions. However, the use of a solution is inconvenient in terms of handling, and the use is limited. In order to eliminate such disadvantages, products in which metal ions are held in a solid such as zeolite have been developed. For example, French Patent Application No. 1061158 describes a marine paint containing 20 to 30% by weight of a zeolite saturated with copper, zinc, silver and the like. Also, Japanese Patent Publication 63-5401
3, JP-A-63-260810 and JP-A-63-2608
JP-A-70764 describes a zeolite composition having further improved antibacterial properties.

[0003] An antibacterial zeolite which does not discolor over time with ultraviolet rays such as sunlight has been proposed (JP-A-63-163).
No. 265809). This relates to an antibacterial zeolite and an antibacterial polymer composition in which part or all of ion-exchangeable ions in the zeolite are replaced with ammonium ions and antibacterial metal ions. However, this antibacterial zeolite lacks thermal stability when only silver ions are retained as an antibacterial metal. In particular, when an A-type zeolite is used, the zeolite itself turns already ocher upon heating at 300 ° C. , Polypropylene resin (kneading temperature 240
C), there is a problem that the color changes to light brown, and the commercial value is significantly impaired.

It is known that antibacterial zeolite particles having a silicone coating are prepared by treating the antibacterial zeolite particles with a solution of a silicone coating agent (Japanese Patent Publication No. 3-80814). This has the advantage that the hygroscopicity can be suppressed to a necessary level, the material has hydrophobicity or water repellency, and no water is released when the compound is molded with the organic polymer to form the compound, so that the forming can be advantageously performed.

[0005]

SUMMARY OF THE INVENTION The present invention has an effect of discoloring a polymer or the like under the influence of heat during processing or under ultraviolet rays such as sunlight when blended with an organic polymer or the like, particularly an organic polymer containing a solvent. It is an object of the present invention to provide a method for producing an extremely small amount of antibacterial zeolite and an antibacterial zeolite thus produced.

[0006]

Means for Solving the Problems The present inventor has focused on the excellent weather resistance of an ethylenically unsaturated compound and the property of being able to form a uniform thin film. By treating the zeolite surface by forming a copolymer of, while maintaining the adhesive force to the zeolite surface originally possessed by the alkoxysilane compound,
The inventors have found that the above-mentioned characteristics can be imparted, and zeolite can be imparted with unprecedented weather resistance, and the present invention has been completed.

That is, the present invention relates to a method for suppressing the discoloring effect of a zeolite supporting an antibacterial metal, wherein the amount of 0.1% by weight of the zeolite supporting an antibacterial metal is reduced.
At least 05 parts by weight of an alkoxysilane monomer containing an ethylenically unsaturated bond and at least 9.95 parts by weight of an ethylenically unsaturated monomer; Sum of 10 to 2
The method is characterized in that the surface of the zeolite is treated with a copolymer which is 00 parts by weight.

[0008] Zeolites carrying antimicrobial metals are known per se and can be made by ion exchange of antimicrobial metals into zeolites. Antibacterial metals include silver, copper,
Zinc, mercury, tin, lead, bismuth, cadmium, chromium,
Cobalt, nickel, or a combination of two or more thereof. Preferably, silver, copper, zinc, or a combination thereof is used. In particular, silver alone or a combination of silver and copper or zinc has excellent antibacterial properties. The effect of the present invention is remarkable particularly in the case of an antibacterial zeolite carrying silver, since the discoloration of the organic polymer under the action of heat and light is relatively large. A method for producing an antibacterial zeolite is described in, for example,
3-54013 and JP-B-3-80814.

[0009] Zeolite is a generally aluminosilicate having a three dimensionally developed skeletal structure, typically based on the _{Al 2 O 3 xM 2 / n} O · Al 2 O 3 · yS
It is represented by iO ₂ .zH ₂ O. M represents an ion-exchangeable metal ion, which is usually a divalent metal;
Corresponds to this valence. On the other hand, x and y represent the coefficients of metal oxide and silica, respectively, and z represents the number of water of crystallization. Many types of zeolites having different composition ratios, pore sizes, specific surface areas, and the like are known.

As the zeolite material used in the present invention, any natural or synthetic zeolite can be used.

For example, natural zeolites include analcin, chabazite, clinoptilolite, erionite, faujasite, mordenite, and philipsite. On the other hand, typical synthetic zeolites include A-type zeolite, X-type zeolite, Y-type zeolite, mordenite and the like, and these synthetic zeolites are suitable as the zeolite material of the present invention. Particularly preferred is a synthetic A-type zeolite, which has a large discoloration effect, so that the effects of the present invention are remarkably exhibited.

The shape of the zeolite is preferably in the form of powder particles, and the particle size may be appropriately selected according to the application. When a thick molded article, for example, various containers, pipes, granules, or thick denier fibers, etc., is used by mixing the bactericidal zeolite of the present invention, the particle size is several microns to several tens microns or several hundred microns or more. On the other hand, when forming into fine denier fiber or film, it is preferable that the particle size is small, for example, in the case of clothing fibers, 5 μm or less,
In particular, it is desirable that the thickness be 2 microns or less. Also, when used for synthetic resin paints such as household paints and various synthetic resin adhesives, those having a small particle size, for example, 3 to 5 microns or less are preferable.

The metal is preferably supported on the zeolite solid particles by an ion exchange reaction. If the metal compound is simply adsorbed or adhered irrespective of ion exchange, the durability of the antibacterial effect of the final product may be insufficient. It is preferred to ion exchange with metal ions in an amount less than the ion exchange capacity of the solid zeolite particles, especially less than about 90% thereof. If the ion exchange is carried out beyond the saturation, the antibacterial effect and its durability may be poor.

As a method for retaining metal ions, a case where various zeolites are converted to Ag-zeolites will be described as an example. Usually, a solution of a water-soluble silver salt such as silver nitrate is used for the conversion of Ag-zeolite, but it is necessary to pay close attention to the concentration and pH of the solution. For example, when an A-type or X-type zeolite (sodium-type) is loaded with silver ions using an ion exchange reaction, if the silver ion concentration is high (for example, when 1 to 2 M AgNO _{3 is} used), ion exchange is performed. As a result, silver ions may be replaced with sodium ions in the solid phase, and at the same time, silver oxides may precipitate in the zeolite solid phase. It is known that the antibacterial activity decreases when silver oxide is deposited. In order to prevent the formation of such a precipitate, the concentration of the silver solution is kept in a diluted state, for example, 0.3 M or less, or an acid is added at the time of ion exchange to prepare the solution.
Preferably, the pH is adjusted to the acidic side. When a silver nitrate solution having such a concentration is used or the pH of the solution is kept on the acidic side, the antibacterial effect can be exerted under the optimum conditions.

When the above-mentioned ion exchange reaction is carried out by a batch method, the zeolite material may be immersed in a salt solution having the above-mentioned concentration or an acidic pH. In order to increase the metal content in the zeolite material, the number of batch processes may be increased. On the other hand, when the zeolite material is treated by the column method using a salt solution having the above-mentioned concentration and pH, the zeolite material is filled in the adsorption tower,
If a salt solution is passed through this, the target metal can be easily
A zeolite is obtained.

The amount of metal in the above-mentioned metal-zeolite (based on anhydrous zeolite) is preferably 20% by weight or less, particularly 0.001 to 5% by weight for silver. For copper and zinc, the amount of copper or zinc in the metal-zeolite (based on anhydrous zeolite) is preferably not more than 25% by weight, especially 0.01 to 15% by weight. Silver,
Copper, zinc and other metal ions can also be used in combination.
In this case, the total amount of the metal ions depends on the composition ratio of the metal ions, but is preferably 25% by weight or less, particularly preferably 0.005% by weight, based on the metal-zeolite (based on anhydrous zeolite).
It is about 1 to 15% by weight.

Further, even if metal ions other than the antibacterial metal, for example, sodium, potassium, calcium, magnesium or other metal ions coexist, they do not hinder the bactericidal effect. No problem.

After ion exchange, the zeolite is usually separated from the liquid and washed. Separation can be performed by any method such as filtration and decantation. The washing treatment method is optional, and for example, washing may be performed with a small amount of distilled water. The washed zeolite may be optionally subjected to a drying treatment. The drying is preferably performed at a temperature of 100 to 500 ° C. under normal pressure or reduced pressure. Particularly preferred drying conditions are 100 to 3 under reduced pressure.
50 ° C. The process may proceed to the next step without drying.

A zeolite carrying an antibacterial metal (hereinafter referred to as an antibacterial zeolite for simplicity) is
Next, it is treated with a copolymer of an alkoxysilane monomer containing an ethylenically unsaturated bond and an ethylenically unsaturated monomer. The treatment is preferably carried out with the antimicrobial zeolite dispersed in an organic solvent, preferably an alcoholic solvent. Solvent dispersions of common synthetic zeolites (and thus antibacterial zeolites) show strong alkalinity, even after several hours or one day, even with the addition or neutralization of acids. In that case, the treatment with the copolymer according to the present invention is preferably carried out at a pH of less than 7, preferably at a pH of 6.5 or less, so that it is necessary to maintain the pH by adding an acid before the treatment.

Therefore, preferably, before, after or simultaneously with supporting the antibacterial metal, zeolite is disclosed in JP-A-3-1973.
No. 13, No. 3-131513, No. 3-164423, No. 3-242317 and Japanese Patent Application No. 2-29.
It is preferable to perform acid immersion according to the method described in the specification of Japanese Patent No. 7841. This basically means that the synthetic zeolite is immersed in an acidic aqueous liquid, and the pH of the immersion liquid is adjusted to a predetermined value of about 7 or less (preferably 4.5 to 7.0, particularly 5.0 to 6.5). The acid is added to keep it, and the immersion lasts until an almost constant pH is maintained for at least 0.5 hour without additional acid. The synthetic zeolite is then washed or used without washing, dried or dried for the next step.

The acidic aqueous solution in which the synthetic zeolite is immersed is an aqueous solution of an inorganic acid and / or an organic acid. For example, hydrochloric acid,
Inorganic acids such as sulfuric acid, nitric acid and phosphoric acid, and organic acids such as formic acid, acetic acid, oxalic acid and tartaric acid can be used. Among them, weak acids, for example, acetic acid, formic acid, tartaric acid, adipic acid,
Boric acid and the like are preferred. Further, it is preferable to add a buffer to the aqueous acid solution. The buffering agent may be any one that imparts a buffering action to the aqueous acid solution, and is typically a combination of various weak acids and salts thereof, for example, acetic acid and sodium acetate, potassium acetate or ammonium acetate, oxalic acid and sodium oxalate, Examples include, but are not limited to, potassium oxalate or ammonium oxalate, combinations of tartaric acid and sodium tartrate, potassium tartrate or ammonium tartrate, phosphoric acid and sodium phosphate, potassium phosphate or ammonium phosphate, and the like. Two or more acids and / or
Alternatively, a buffer may be mixed and used.

Although a certain effect can be obtained by washing instead of the above immersion, the effect is small. In addition,
In the case of natural zeolites, since they do not originally exhibit alkalinity, the above-mentioned immersion or washing effect is not so significant.

In the present invention, the copolymer for treating the antibacterial zeolite is used in an amount of 0.05 part by weight or more, preferably 0.5 part by weight or more, particularly preferably 2.0 parts by weight, per 1000 parts by weight of the antibacterial zeolite. At least 9.95 parts by weight, preferably at least 9.5 parts by weight, particularly preferably at least 8.0 parts by weight of an ethylenically unsaturated monomer having an ethylenically unsaturated bond in an amount of at least 9. Consists of at least a body. If the amount is less than the above, discoloration of zeolite cannot be prevented, which is not preferable. In the above copolymer,
The copolymerization ratio of the alkoxysilane monomer to the ethylenically unsaturated monomer is preferably at least 0.5 / 9.5, more preferably at least 2.0 / 8.0 by weight. By employing the copolymerization ratio, the adhesion strength of the alkoxysilane monomer and the weather resistance and the film forming property of the ethylenically unsaturated monomer can be produced in a well-balanced manner.
A film having no unevenness and excellent adhesion can be formed on the zeolite surface. Therefore, there is no peeling of the film due to kneading with the organic polymer, and extremely good weather resistance can be provided.

In the above copolymer, the total of the alkoxysilane monomer and the ethylenically unsaturated monomer is 10 to 200 parts by weight, preferably 20 to 150 parts by weight, per 1000 parts by weight of the antibacterial zeolite. Parts, particularly preferably 25 to 100 parts by weight. If the total is less than the above lower limit, the discoloring action of the antibacterial zeolite will not be improved, and if it exceeds the upper limit, the antibacterial zeolite will not be able to maintain the antibacterial activity, which is not preferable. As the alkoxysilane monomer used in the present invention, those represented by the following formula (I) are preferable.

[0025]

Embedded image (Where R is a hydrogen atom or a methyl group; Z is-
(CH _{2) n} - or _{-C (O) O (CH 2} ) n - , wherein n is an integer of 0 to 3; X is -OCH _3,
-OC ₂ H ₅ or _{-O (CH 2) m -O- (} CH 2) p
-H, wherein m and p represent an integer of 1 to 3; Y is-(CH ₂ ) _q -H, wherein q represents an integer of 0 to 3; Indicates an integer. Examples of the alkoxysilane monomer include vinylethoxysilane, vinyltris (2-methoxyethoxysilane), and 3-methacryloxypropyltrimethoxysilane.

As the ethylenically unsaturated monomer, acrylic acid, methacrylic acid, or a derivative thereof is preferable.
For example, acrylic acid; methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, isobutyl acrylate, isooctyl acrylate,
Acrylates such as isononyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate; metal acrylates such as zinc acrylate; methacrylic acid; methyl methacrylate, butyl methacrylate;
Isobutyl methacrylate, tertiary butyl methacrylate, cyclohexyl methacrylate, 2-methacrylic acid
Examples include methacrylic acid esters such as hydroxyethyl and 2-hydroxypropyl methacrylate.

In a particularly preferred combination of the alkoxysilane monomer and the ethylenically unsaturated monomer, the alkoxysilane monomer is 3-methacryloxypropyltrimethoxysilane or vinyltris (2-methoxyethoxy) silane, The ethylenically unsaturated monomer is a methacrylate or an acrylate.

The polymerization reaction between the alkoxysilane monomer and the ethylenically unsaturated monomer is preferably carried out in an organic solvent. Preferably, the polymerization reaction can be carried out in a system in which an antibacterial zeolite is dispersed in a slurry in an alcoholic organic solvent such as methanol, ethanol, normal propyl alcohol, or isopropyl alcohol.
Some water may be present in the slurry;
A third substance such as an H regulator may also be present. The organic solvent is preferably used in an amount equal to or more than the above-mentioned zeolite in a weight ratio, particularly preferably in an amount equal to or more than twice the amount. The reaction temperature is preferably at least 30 ° C., particularly preferably the reflux temperature of the system used, at which temperature the copolymerization reaction is carried out preferably for at least 1 hour, particularly preferably for at least 2 hours. Thereby, the surface treatment of the zeolite is performed. Further, it is preferable to use a polymerization initiator, and the amount of the polymerization initiator to be used is preferably 0.001 to 5% by weight, particularly preferably, to the total amount of the alkoxysilane monomer and the ethylenically unsaturated monomer. It is in the range of 0.01 to 2% by weight. As the polymerization initiator, benzoyl peroxide or azoisobutyronitrile is preferably used, but is not limited thereto. Although the treatment of the antibacterial zeolite may be carried out after polymerization of the alkoxysilane monomer and the ethylenically unsaturated monomer to produce a copolymer in advance,
Preferably, by performing the polymerization and the antibacterial zeolite treatment simultaneously as described above, it is possible to carry out efficiently, more simply and economically.

Further, in order to facilitate the formation of a copolymer film on the zeolite surface, for example, butyl cellosolve, ethyl cellosolve, etc., and a silicone type antifoaming agent can be used as an auxiliary agent. The addition of the above substances does not prevent the polymerization of the alkoxysilane monomer and the ethylenically unsaturated monomer.

After the treatment with the copolymer, the antibacterial zeolite is usually separated from the organic solvent, and then washed and dried. The separation operation is optional, and can be performed by, for example, a method such as filtration or decantation. Further, the washing may be omitted. The drying treatment is preferably performed at normal pressure or reduced pressure at a temperature near the boiling point of the organic solvent used. By the treatment of the present invention, a copolymer comprising at least an alkoxysilane monomer and an ethylenically unsaturated monomer is formed on the surface of the antibacterial zeolite, but the antibacterial property is not impaired.
The antibacterial zeolite surface-treated according to the present invention is subjected to the treatment in a total amount of the alkoxysilane monomer and the ethylenically unsaturated monomer of 200 parts by weight or less based on 1,000 parts by weight of the antibacterial zeolite. It shows the same antibacterial properties that are practically comparable to those of the non-antibacterial zeolites.

The antimicrobial zeolite obtained in the present invention can be used in the same field as conventional antimicrobial zeolites, and is particularly blended with any low molecular weight or high molecular weight organic polymer to exhibit antimicrobial properties. Does not discolor the organic polymer formulation. Examples of the organic polymer include polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyamide, polyester, polyester elastomer, polyvinyl alcohol, polycarbonate, polyacetal, ABS resin,
Thermoplastic synthetic polymers such as acrylic resin, vinyl acetate resin, fluorine resin and polyurethane; thermosetting synthetic polymers such as phenolic resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, urethane resin, rayon, cupra , Acetate, triacetate and the like, or regenerated or semi-synthetic polymers. Further, it can be blended with paper raw materials in papermaking and the like. In particular, in the case of polyolefins such as residual catalyst, polyethylene having a reactive end group, and polypropylene, when a conventional antibacterial zeolite, especially a silver-supported zeolite is blended, heat over processing or ultraviolet light such as sunlight at the time of use causes Where discoloration was liable to occur, discoloration was significantly suppressed when the antibacterial zeolite treated according to the present invention was used. In addition, the antibacterial zeolite itself obtained in the present invention also has high whiteness,
In addition, since it can be well dispersed in synthetic polymer resins in a wide range of low molecular weight to high molecular weight, it is suitable for use in the food, medical and environmental fields, for example, in the form of fibers, films and other molded articles. Further, since the antibacterial zeolite itself is stable, it can be applied to a wide range of polymers including coating agents, adhesives and the like. In addition, it can also be used together with another antibacterial agent, especially an organic antibacterial agent.

In particular, the antibacterial zeolite obtained in the present invention tends to have excellent dispersibility and compatibility with low-molecular-weight organic polymers, and is required to have various coating properties such as pressure-sensitive adhesives, adhesives and paints. It can be effectively used for paints that can be used. The antibacterial zeolite has excellent antibacterial properties, high whiteness, and excellent compoundability with organic polymers, particularly low molecular weight organic polymers. Therefore, use in fields where discoloration prevention is important, for example, application to a wide range of polymers including various life-related polymer materials requiring cleanliness and comfort such as bedrooms, bathrooms, kitchens, washrooms, living rooms, etc. Is possible. In addition, it has become possible to obtain antibacterial polymer products that can guarantee long-term stable quality, such as wallpaper adhesives, woodwork and wall repair agents, enamel fillers, jointing agents, and water leakage inhibitors.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0034]

【Example】

[0035]

Examples 1 to 7 and Comparative Examples 1 to 8 The whiteness was determined by blending a surface-treated antibacterial zeolite with an organic polymer as described below to prepare a plate, and determining the Hunter whiteness of each plate by T.
It was measured and evaluated with a C-1 type colorimeter (manufactured by Tokyo Denshoku Industries Co., Ltd.).

Antibacterial properties include Escherichia coli,
Pseudomonas aeruginosa or Aspergillus (Asper)
gillus niger) and the minimum inhibitory concentration (MIC) of each surface treated antimicrobial zeolite was determined and evaluated.

Carrying of antimicrobial metal (ion exchange ) Commercial zeolite A (Ethyl, average particle size 2.0 μm)
m) 2000 g was dispersed in 10 liters of ion-exchanged water, boiled for 1 hour, and then sufficiently washed and filtered. The zeolite A was used as a starting material.

The A-type zeolite after the above-mentioned boiling and washing was put into a reaction tank equipped with a stirrer having a capacity of 20 liters, and dispersed in ion-exchanged water to form a slurry of 10 liters.
Stirring was continued at 00 rpm (initial pH 11). Then 1
The pH of the zeolite slurry was adjusted to 5.5 by slowly adding 0% nitric acid aqueous solution. After stirring for 30 minutes, silver nitrate (A
Gno ₃₎ 120 g, zinc nitrate _{(Zn (NO 3) 2 ·} 6
H ₂ O) 700 g was added gradually over 30 minutes a solution prepared by dissolving in deionized water for 5 liters then the temperature 65 ° C.
And the mixture was further stirred for 5 hours to complete the ion exchange reaction of the antibacterial ions. Subsequently, after solid-liquid separation using a Buchner filter and washing with ion-exchanged water, the solid was
Dry for hours and crush the mass. An antibacterial zeolite with high whiteness was obtained.

Alkoxysilane monomer and ethylenically unsaturated
Treatment with a copolymer comprising a sum monomer As an alkoxysilane monomer, 3-methacryloxypropyltrimethoxysilane [wherein R is a methyl group and Z is -COO (CH ₂ ) _3- Yes, X is -OC
H ₃ and a is 3], methyl methacrylate and 2-ethylhexyl acrylate as ethylenically unsaturated monomers, and azobisisobutyronitrile as a polymerization initiator.

Into a four-necked flask equipped with a stirring blade, a dropping funnel, a thermometer and a reflux condenser were charged 1000 g of the above antibacterial zeolite and 2000 g of isopropyl alcohol, and after stirring, the polymerization initiator was added to Tables 1 and 2. (G). Next, the amount (g) of each monomer shown in Tables 1 and 2 was put into the dropping funnel, and the mixture was dropped at reflux temperature for 4 hours under stirring to carry out a polymerization reaction. 0.05 g of isobutyronitrile was added, and the mixture was stirred for 2 hours to complete the reaction. Next, after the temperature was lowered to 65 ° C., isopropyl alcohol was recovered under reduced pressure, and the obtained antibacterial zeolite after the surface treatment was placed in a hot air dryer at 130 ° C. for 1 hour to remove the remaining isopropyl alcohol. Volatilized. Put the antibacterial zeolite in a ball mill, crush the lump and pass through a 325 mesh metal sieve,
Those that did not pass through were crushed again with a ball mill and the operation of passing through a 325 mesh metal sieve was repeated.

Blending to Organic Polymer As an organic polymer, a polypropylene chip (KJ-20)
9, Ace Polymer Co., Ltd.). Each of the antibacterial zeolite and the polypropylene resin is 105
It was used after preliminarily drying at 2 ° C. for 2 hours. The amount of the antibacterial zeolite in the resin was 2.0% by weight.

An antibacterial zeolite and a polypropylene resin were supplied to an injection molding machine (MODEL IS-EPN type, manufactured by Toshiba Machine Co., Ltd.), and an injection temperature of 200 ° C. and 50 mm
A 90 mm x 5 mm plate was made.

Tables 1 and 2 show the antibacterial properties of the antibacterial zeolite after the surface treatment and the Hunter whiteness of each plate.

[0044]

[Table 1]

[0045]

[Table 2] In Examples 1 to 5, the weight ratio of the alkoxysilane monomer to the ethylenically unsaturated monomer was kept constant at 0.053, and the total amount of both was changed within the range of the present invention. is there. Increasing the total amount increased hunter whiteness. It was also found that the antibacterial property maintained a good value. In Example 6, the weight ratio was set to 0.005, and in Example 7, the weight ratio was set to 0.429.
The total amount of the monomers is the same as in Example 3. It was found that when the weight ratio was decreased, the Hunter whiteness was decreased, and when the weight ratio was increased, the Hunter whiteness was increased. In addition, the antibacterial properties all maintained good values. In Comparative Examples 1 to 6, the alkoxysilane monomer was not added. Hunter whiteness was low in each case. In Comparative Example 6, the antibacterial property also deteriorated because the amount of the ethylenically unsaturated monomer added was large. Comparative Example 7
As in Examples 1 to 5, the weight ratio of the alkoxysilane monomer to the ethylenically unsaturated monomer was set to 0.053, but the sum of the added amounts exceeded the range of the present invention. Hunter whiteness was good, but antibacterial properties deteriorated.
In Comparative Example 8, the addition amount of the alkoxysilane monomer was small. Hunter whiteness was found to be low. In Comparative Example 9, the surface was treated only with the alkoxysilane monomer. Good antibacterial properties were obtained, but Hunter whiteness was low. In Comparative Example 10, no surface treatment was performed. Antibacterial properties are good, but hunter whiteness,
It was significantly lower than in the examples. From the above,
It was found that the antibacterial zeolite obtained according to the present invention had better antibacterial properties and whiteness than the comparative examples.

Each of these plates was placed for three months near a room window exposed to direct sunlight, and observation was continued. The whiteness of the plate of the present invention hardly changed, and the whiteness at the initial stage of molding was maintained.
On the other hand, the plate of the comparative example gradually decreased in whiteness and turned brownish, and after approximately one month, considerable coloring was noticeable.

[0047]

Example 8 and Comparative Example 11 Commercially available aqueous white synthetic resin paints (Asahi Pen Co., Ltd., paints for home use, indoor walls and bathrooms, acrylic resin white No. 1 paint) were used in Examples 3 and Comparative Example 3. The antibacterial zeolite after the surface treatment prepared in the above was blended. The compounding amount was 0.5 part by weight of the antibacterial zeolite after the surface treatment with respect to 100 parts by weight of the paint, and the mixture was stirred for 10 minutes with a homogenizer. Separately, as a control, the antibacterial zeolite having no surface treatment and the paint were similarly mixed by stirring.

The paint containing the antibacterial zeolite was repeatedly applied to cedar wood twice, allowed to dry naturally, and one week later, the Hunter whiteness of the surface was measured. As a blank test, a paint containing no antibacterial zeolite was used. Table 3 shows the results. Example 8 had better hunter whiteness than Comparative Example 11 and the control. In addition, the decrease in hunter whiteness was smaller than that of the blank.

[0049]

[Table 3] The above painted cedar wood was hung outdoors and kept for three months, and observation was continued. The whiteness of the white painted plate of Example 8 hardly changed, and the whiteness at the initial stage of painting was maintained. On the other hand, Comparative Example 11
The whiteness of the control product gradually decreased, and the discoloration became noticeable after about one month.

[0050]

Example 9 and Comparative Example 12 Commercially available oil-based white synthetic resin paints (manufactured by Nippon Paint Co., Ltd., gates, fences, shutters, garage applications, indoor and outdoor paints, oil-based phthalate resins, white home paint) The antibacterial zeolite after the surface treatment or the untreated antibacterial zeolite was blended in the same manner as in Example 8.

The paint thus obtained was diluted with a paint thinner to a substantially equal weight ratio immediately before application. This was repeatedly applied to an aluminum plate twice and air-dried. One week later, the hunter whiteness of the surface was measured. The results are shown in Table 4. Example 9
Showed that the Hunter whiteness was better than that of Comparative Example 12 or the control. In addition, the decrease in hunter whiteness was smaller than that of the blank.

[0052]

[Table 4] The coated aluminum plate was suspended outdoors and kept for three months, and observation was continued. The whiteness of the white painted plate of Example 9 hardly changed, and the whiteness at the beginning of painting was maintained. On the other hand, it was observed that the discoloration gradually progressed in the comparative example and the control product.

[0053]

Example 10 1.4% by weight of the surface-treated antibacterial zeolite prepared in Example 3 was blended with an acrylic resin emulsion (Boncoat R-3020, trade name, manufactured by Dainippon Ink and Chemicals, Inc.). Polyester / cotton (30/70) fabric was immersed in the solution, and then squeezed through a mangle adjusted to a squeezing ratio of 70% to impregnate the fabric with the acrylic resin containing the antibacterial zeolite. Then, 1
Curing treatment was performed at 20 ° C. for 5 minutes and at 160 ° C. for 30 seconds to obtain a resin-treated cloth having a basis weight of about 140 g / m ² .

As a separate control, the same resin processing as described above was performed using an antibacterial zeolite that had not been surface-treated.

The antibacterial test was carried out according to the SEK method by a shake flask method. As a shaker, a wrist action shaker [Burrel Corporation (Bur
rell Corporation (Pittsburgh, PA, USA), Model-75]. The weight ratio of the dough: liquid was 1: 100. As the bacterial species, Klebsiella pneumoniae (K
lebsiella Pneumoniae) <K. Pneumoniae ATCC 4352> was used.

The outline of the antibacterial test method is as follows. (1) First, a bacterial solution is prepared, and the amount is adjusted so that the bacterial amount becomes 1.4 × 10 ⁴ . (2) 0.75 g of dough (a square having a side length of about 10 mm) is placed in a 200 ml sealed flask. Next, 75 cc of a solution containing 1.4 × 10 ⁴ bacteria is added. (3) After sealing the flask, it is shaken at 25 ° C. for 1 hour using the wrist action shaker described above. (4) After shaking, the bacterial solution and the dough are separated, the bacterial solution is applied to an agar medium, and cultured to form a colony. (5) Count the colonies and determine the number of viable bacteria one hour after shaking. Similarly, the number of viable bacteria at 0 hour of shaking is determined.

The washing test was performed according to JIS L-0217, 1
The test was performed in accordance with Method 03.

The weather resistance test was carried out with a weatherometer according to JIS L-0842. Irradiation time is 5
0 hours.

The discoloration in the initial discoloration and discoloration was evaluated by evaluating the degree of discoloration by a gray scale (standard discoloration measure).
The numbers in Table 6 indicate the following contents.

5: Very good 4: Good 3: Somewhat bad 2: Bad 1: Notably bad The results are shown in Tables 5 and 6. In Table 5, “fabric only” is obtained by conducting an antibacterial test on a fabric not impregnated with an acrylic resin and an antibacterial zeolite,
In the blank test, an antibacterial test was performed using only bacteria without using any fabric.

[0061]

[Table 5] Table 5 Number of washings Shaking Shaking Sterilization rate (times) 0 hour 1 hour Colony Colony (%) Fabric of the present invention 0 1.4 × 10 ⁴ 900 93.6 10 1.4 × 10 ⁴ 1.6 × 10 ³ 88.6 Fabric for control product 0 1.4 × 10 ⁴ 400 97.1 10 1.4 × 10 ⁴ 1.0 × 10 ³ 92.9 Fabric only 0 1.4 × 10 ⁴ 1.2 × 10 ⁴ 14.2 10 1.4 × 10 ⁴ 1.4 × 10 ⁴ 0 Blank test 1.4 × 10 ⁴ 1.4 × 10 ⁴ 0

[0062]

[Table 6] The fabric impregnated with the acrylic resin blended with the antibacterial zeolite treated according to the present invention (the fabric of the present invention) is the fabric impregnated with the acrylic resin blended with the antibacterial zeolite not treated (control As compared with the product fabric), almost the same sterilization rate was obtained when the number of times of washing was 0 and 10 times, and it was found that good antibacterial properties could be maintained even when the treatment of the present invention was performed. Was. In addition, in the case of only cloth,
The sterilization rate is significantly lower. In the initial discoloration and discoloration, the fabric of the present invention is better than the control fabric,
It turned out that it was excellent in light resistance. Further, it was found that the fabric of the present invention had good initial fading and the same degree of discoloration and fading did not change even when compared with the fabric without any impregnation.

[0063]

The antibacterial zeolite treated according to the present invention, when incorporated into an organic polymer, has a very little effect of discoloring the polymer under the influence of heat during processing or under ultraviolet rays such as sunlight. There is no decrease in antibacterial properties due to the treatment.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-176423 (JP, A) JP-A-4-224505 (JP, A) JP-A-4-66512 (JP, A) 269030 (JP, A) JP-A-1-164722 (JP, A) JP-A-62-27746 (JP, A) JP-A-62-17748 (JP, A) JP-A-6-1680 (JP, A) JP-A-6-166830 (JP, A) JP-A-6-116530 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C01B 39/00-39/54 A01N 59/16 A01N 25/08 JICST file (JOIS)

Claims (5)

(57) [Claims] 1. A method for suppressing the discoloration effect of a zeolite carrying an antibacterial metal, comprising: an alkoxy containing 0.05% by weight or more of an ethylenically unsaturated bond with respect to 1000 parts by weight of a zeolite carrying an antibacterial metal. The silane monomer and at least 9.95 parts by weight of an ethylenically unsaturated monomer, and the total of the alkoxysilane monomer and the ethylenically unsaturated monomer is 10 to 200 parts by weight. A method comprising subjecting the above zeolite to a surface treatment with a copolymer. 2. The method of claim 1 wherein the weight ratio of said alkoxysilane monomer to ethylenically unsaturated monomer is 0.5 / 9.5 or more. 3. The alkoxysilane monomer is a substance represented by the following formula (I): (Where R is a hydrogen atom or a methyl group; Z is-
(CH _{2) n} - or _{-C (O) O (CH 2} ) n - , wherein n is an integer of 0 to 3, X is -OCH _3,
-OC ₂ H ₅ or _{-O (CH 2) m -O- (} CH 2) p
-H, wherein m and p each independently represent an integer from 1 to 3; Y is-(CH ₂ ) _q -H, where q
Represents an integer of 0 to 3; a represents an integer of 1 to 3), and the ethylenically unsaturated monomer is acrylic acid, methacrylic acid or a derivative thereof. 4. The treatment with the copolymer by carrying out a polymerization reaction of the alkoxysilane monomer and the ethylenically unsaturated monomer in the presence of a zeolite carrying an antibacterial metal. 3. The method according to any one of 3. 5. The method according to claim 1, wherein the alkoxysilane monomer is 3-methacryloxypropyltrimethoxysilane or vinyltris (2-methoxyethoxy) silane.