JP2911282B2 - Antimicrobial agent and antimicrobial resin or rubber composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel antimicrobial agent. More specifically, it is non-toxic or extremely non-toxic in itself, has high heat resistance and weather resistance, is fine particles and has excellent dispersibility in resins, rubbers and paints. An antimicrobial agent having features such as improving thermal stability, specifically, an antibacterial agent,
It relates to an antifungal agent.

[0002]

2. Description of the Related Art The temperature is relatively high and the humidity is high.
Climate climates such as Japan are suitable for microbial propagation. For this reason, microorganisms (germs) may be generated in drinking water, food, and the like, which may have a serious effect on human life. Food, cosmetics, plastic products, wallpaper, interior and exterior products for automobiles, building materials, electric wires, cables, synthetic leather, sealants, rubber hoses, adhesives, roofing, flooring, wood,
Microorganisms (molds) occur in paints and the like, causing discoloration, odor, and strength deterioration. For example, an electric wire leads to electric leakage, which may cause fire, electric shock, and the like. In addition, damage of precious cultural assets by microorganisms, cancer caused by mold on plastics, development of allergic pneumonia, occurrence of large numbers of mites feeding on the generated bacteria, athlete's foot caused by Trichophyton parasite,
It causes damage such as the onset of vulgaris.

[0003] The need to prevent the above-mentioned microbial disaster has been increasing more and more in recent years, and various antimicrobial agents are commercially available. When these antimicrobial agents are classified, halogen compounds containing chlorine, bromine, iodine, etc .; inorganic compounds such as glass containing copper arsenite, cuprous oxide, silver nitrate, silver, copper, etc .; amines, triazines, etc. Organic compounds such as arsenic, copper, mercury, tin and zinc; organic sulfur compounds such as isothiazolone, pyrithione and thiocyanate; quaternary ammonium compounds such as alkyldimethylbenzylammonium compounds; chlorinated phenols and bisphenols And phenol compounds such as O-phenylphenol.

[0004]

As a recent trend, safety and impact on the environment have been emphasized, and this trend is considered to be further strengthened. However, many of the existing antimicrobial agents are highly toxic, and many of them are water-soluble and environmental pollution cannot be ignored.

[0005] Furthermore, the addition of existing antimicrobial agents can reduce the heat resistance and weather resistance of products, decompose resins and rubbers at processing temperatures,
Foaming, poor dispersion in paint due to coarse particles,
Problems such as a decrease in the appearance of the product and a decrease in the mechanical strength have occurred.

An object of the present invention is to provide an antimicrobial agent which is non-toxic or nearly non-toxic and insoluble or hardly soluble in water or an organic solvent and does not cause a problem of environmental pollution. Further, the present invention is itself heat and ultraviolet light stable, resin,
An object of the present invention is to provide an antimicrobial agent that is well dispersed in rubber and paint and does not impair the characteristics of products, and a resin or rubber composition containing the antimicrobial agent.

[0007] The present invention has the following formula _{^{(1) (M 1 2+)}} 1-x (M 2 2+) x (OH) 2 (1) [ in the _formula, the ^{M 1 2+} is Mg and / or Ca, _{M 2}
²⁺ represents Cu and / or Zn, and x is 0.000
1 ≦ x <0.9, preferably 0.0001 ≦ x ≦ 0.
4, more preferably a number in the range of 0.0001 ≦ x ≦ 0.2] is provided as an active ingredient.

In the present invention, the antimicrobial agent is added in an amount of 0.001 to 50 parts by weight, preferably 0.001 to 15 parts by weight, more preferably 0.01 to 5 parts by weight, based on 100 parts by weight of the resin or rubber. An antimicrobial resin or rubber composition is provided.

The present inventors have found that existing organic antimicrobial agents have problems in toxicity, heat resistance, and weather resistance, while inorganic compound agents have low effects and impair the properties of resins and rubbers. Therefore, attention was paid to the fact that copper ions and zinc ions are extremely low in toxicity or non-toxic and inexpensive. Furthermore, as a result of earnestly studying the cause of the above problems of the copper and zinc based inorganic antimicrobial agents, it was presumed that they were poorly soluble in water.

That is, since it is hardly soluble, the concentrations of copper ions and zinc ions, which are active ingredients, are hardly increased to a concentration at which an effect is obtained, and existing antimicrobial agents such as cuprous oxide, zinc oxide, etc. It is presumed that the solid acidity deteriorates the heat resistance and weather resistance of the resin and rubber.

Accordingly, the present inventors have made intensive studies to simultaneously solve the problems of the above-mentioned inorganic compound antimicrobial agents and completed the present invention. That is, the present inventor has proposed that Ca (OH) ₂ and / or
Or Mg (OH) _2, by solid solution Cu ²⁺ and / or Zn ²⁺ as an active ingredient, a Cu ²⁺ and / or Zn ^2+, Ca (OH) ₂ or Mg (OH) ₂
Solubility in water, that is, a level of
It was found that the antimicrobial activity could be remarkably improved. Ca (OH) ₂
Since Mg and (OH) ₂ are solid bases, they have the function of improving the heat resistance and weather resistance of resins and rubbers.
The decomposition onset temperature of the composite metal hydroxide of the present invention is about 30.
The temperature is 0 ° C. or higher, and there is no problem of decomposition or foaming at the processing temperature of resin or rubber. Further, it has been found that the use of the compound of the formula (1) in which the concentrations of copper ions and zinc ions are considerably reduced has the advantage that the antimicrobial property can be exerted, the toxicity is further reduced, and further, the toxicity is reduced. Was. Further, the compound of the formula (1) containing zinc ions has an advantage that it has excellent whiteness and does not color the added resin and the like.

The compound of the present invention represented by the formula (1) is a novel compound discovered by the present inventor and disclosed in Japanese Patent Application No. 3-36.
No. 813 and the patent application “Composite metal hydroxide and method for producing the same” on Nov. 7, 1991
Ca (OH) ₂ or M in which Cu ²⁺ and / or Zn ²⁺ are dissolved in a (OH) ₂ and / or Mg (OH) ₂
It is a compound having the same crystal structure as g (OH) _2, and gives almost the same diffraction pattern as Ca (OH) ₂ and Mg (OH) ₂ by powder X-ray diffraction.

In the equation (1), when the value of x is 0.9 or more,
Does not produce the solid solution of the formula (1) and shows almost no antimicrobial effect. If the value of x exceeds 0.4, Ca (O
H) ₂ or basic salts and oxides of copper and zinc which do not form a solid solution in Mg (OH) ₂ are liable to be produced as by-products, so that the antimicrobial effect levels off, which is not preferable. If the value of x is too small, the release concentration of copper ions and / or zinc ions, which are active ingredients, will be low, and the effect of the present invention will be insufficient. In addition, as the concentration of copper and / or zinc in the compound of the formula (1) increases, the release of copper ions and / or zinc ions from water tends to decrease, and the antimicrobial effect tends to be insufficient. Therefore, the range of x of the antimicrobial agent of the present invention is:
0.0001 ≦ x <0.9, preferably 0.0001 ≦
x ≦ 0.4, more preferably 0.001 ≦ x ≦ 0.2
It is. In the present invention, the by-produced basic salts, oxides and hydroxides of copper and zinc may be used as an antimicrobial agent in a state of being mixed with the composite metal hydroxide of the formula (1). Absent.

[0014] The method for producing an antimicrobial agent of the present invention comprises the ^{steps of:}
And / or Mg ²⁺ and Cu ²⁺ and / or Zn ²⁺
And an aqueous solution containing substantially no more than the equivalent of the total amount of these cations, and allowed to react under stirring. If necessary, the reaction product was further heated to about 100 to 200 ° C.
After hydrothermal treatment using an autoclave in step (1), it is manufactured by appropriately selecting and using conventional means such as washing, dehydration, drying, pulverization, and classification. Dispersibility in resin and rubber,
To further enhance the affinity, using an anionic surfactant, aluminum, titanate coupling agent, etc.
Surface treatment may be performed by a conventional method.

The fields of application of the antimicrobial agent of the present invention include:
Drinking water, food, resin, rubber, wallpaper, bathroom interior materials, electric wires,
Flooring, shower curtain, urethane foam, buoy rope,
Vinyl sheets, agricultural films, synthetic leather, sealants, building materials, furniture, textiles such as cloth, tents, socks,
Non-woven fabrics, paints, adhesives, wood, bamboo, cosmetics, pools,
Examples include various fields that may be adversely affected by microorganisms, such as cooling towers.

The amount of the antimicrobial agent of the present invention depends on the amount of the target substance 1
0.001 to 50 parts by weight, preferably 0.001 to 15 parts by weight, more preferably 0.01 part by weight, per 100 parts by weight.
The amount is 1 to 5 parts by weight, but can be appropriately selected depending on the application. The antimicrobial agent of the present invention has an average secondary particle size of about 0.1 to 1 μm.
And are stable at processing temperatures up to about 300 ° C., and are also stable to ultraviolet light.
Therefore, the fibers can be kneaded and dispersed before being spun and then spun. In addition, since good dispersibility is exhibited without causing troubles such as decomposition and foaming at the processing temperature of resin or rubber, not only the appearance of the molded product but also the mechanical strength is not impaired.

Since the antimicrobial agent of the present invention is a solid base, it acts to neutralize acids and halogens and inactivate them.
Since it is equal to or more than (OH) ₂ or Ca (OH) _2, it improves the thermal stability and weather resistance of resin and rubber.

The resins and rubbers used in the present invention are exemplified as follows, but are not limited to these resins and rubbers. Polyethylene, copolymers of ethylene and other olefins, ethylene and vinyl acetate, copolymers of ethyl acrylate or methyl acrylate, polypropylene, copolymers of propylene and other α-olefins, polybutene-1, Polystyrene, copolymer of styrene and acrylonitrile, ethylene and propylene diene rubber or butadiene, vinyl acetate, polyacrylate, polymethacrylate, polyurethane, polyester, polyether, polyamide, polyvinyl chloride, copolymer of vinyl chloride and vinyl acetate Thermoplastic resins such as phenolic resin, melamine resin, epoxy resin, unsaturated polyester resin, alkyd resin, EPDM, SBR, NBR, butyl rubber, isoprene rubber, chlorosulfonated resin Rubber such as ethylene.

Hereinafter, the present invention will be described in more detail with reference to examples. Example 1 500 ml of 2.0 mol / l Ca (OH) ₂ slurry and 5 mol of 1.0 mol / l zinc nitrate aqueous solution
The whole amount of 0 ml was added to a 1-liter stainless steel container previously containing 200 ml of deionized water at 40 ° C. under stirring for about 2 minutes, and then stirring was continued for another 10 minutes to cause a reaction. The obtained white slurry was dehydrated, washed with water, dried and pulverized.

The powder X-ray diffraction pattern of the pulverized material was Ca (OH) ₂ except that it was slightly shifted to the higher angle side.
The diffraction pattern was the same. After the chemical composition was subjected to dispersion treatment with ultrasonic waves by a chelate titration method, the average secondary particle diameter was measured by a microtrack method using a laser beam. In the antibacterial test, the minimum concentration at which the growth of bacteria was inhibited was defined as the minimum growth inhibitory concentration after the bacterial solution for inoculation prepared at an arbitrary concentration was spread on an agar plate medium and cultured. The lower the concentration, the higher the antibacterial property. Table 1 shows the measurement results.

Example 2 500 ml of a mixed aqueous solution of 1.1 mol / l of calcium chloride and 0.9 mol / l of zinc nitrate,
500 ml of 4 mol / l sodium hydroxide was simultaneously added to a 2 liter stainless steel container preliminarily added with 300 ml of deionized water at 40 ° C. under stirring for about 5 minutes, and reacted. The reaction was filtered, washed with water, dried and pulverized.

The X-ray diffraction pattern of this powder was the same as that of Ca (OH) ₂ except that it shifted slightly to the higher angle side, and Ca [Zn (OH) ₃ ] ₂ .2H ₂ O
Showed a diffraction pattern. Table 1 shows the measurement results.

Example 3 500 ml of a mixed aqueous solution of 1.96 mol / l of calcium chloride and 0.04 mol / l of zinc chloride and 500 ml of 4 mol / l of potassium hydroxide were prepared in the same manner as in Example 2. The procedure yielded a powder. The X-ray diffraction pattern of this powder was the same as that of Ca (OH) ₂ except that it shifted slightly to the higher angle side. Table 1 shows the measurement results.

Example 4 A powder was obtained by operating 500 ml of a 2 mol / l Ca (OH) ₂ slurry and 150 ml of a 1.0 mol / l cupric chloride aqueous solution in the same manner as in Example 1. Was. The X-ray diffraction pattern of this powder was the same as that of Ca (OH) ₂ except that it shifted slightly to the higher angle side. Table 1 shows the measurement results.

Example 5 500 ml of a 2 mol / l Ca (OH) ₂ slurry and 550 ml of a 1.0 mol / l cupric chloride aqueous solution were stirred by adding deionized water at 30 ° C. in advance. The mixture was added almost at the same time to a reaction vessel having a capacity of 2 liters, and the whole amount was added in about 5 minutes. Then, stirring was continued for about 10 minutes to further react. Thereafter, the same treatment as in Example 1 was performed to obtain a powder. The X-ray diffraction pattern of this powder showed the same diffraction pattern as that of Ca (OH) ₂ except that it slightly shifted to a higher angle side, and the diffraction pattern of basic copper chloride.
Table 1 shows the measurement results.

EXAMPLE 6 2 mol / l of aqueous ammonia 600 was added to 5 liter of 3.0 mol / l aqueous solution of magnesium chloride while stirring.
Milliliter was added, and the reaction was maintained at 40 ° C. for 5 days. To this system was added 20 ml of a 1.0 mol / l cupric chloride aqueous solution, and the mixture was allowed to react for about 30 minutes. The mixture was then dehydrated, washed with water, and the dehydrated cake was heated to 90 ° C. at 5 mol / l. Sodium hydroxide solution 50
The mixture was added to 0 ml with stirring and reacted for about 20 minutes. After the reaction, the mixture was filtered, washed with water, dried, and then sieved. This powder was a crystal having a fibrous outer shape, and was the same as the diffraction pattern of Mg (OH) ₂ except that the powder X-ray diffraction pattern was slightly shifted to a lower angle side. Table 1 shows the measurement results.

Example 7 500 ml of a mixed aqueous solution of 0.2 mol / l of magnesium chloride and 0.12 mol / l of zinc nitrate and 50 mol of a 2.0 mol / l Ca (OH) ₂ slurry 50
0 ml was reacted in the same manner as in Example 1 to obtain a powder. The X-ray diffraction pattern of this powder was the same as that of Mg (OH) ₂ except that it shifted slightly to the lower angle side. Table 1 shows the measurement results.

COMPARATIVE EXAMPLE 1 500 ml of a mixed aqueous solution of 0.2 mol / l of calcium chloride and 1.8 mol / l of zinc nitrate,
The reaction was carried out in the same manner as in Example 2 with 4 ml / liter of sodium hydroxide (500 ml) to obtain a powder. The X-ray diffraction pattern of this powder was only ZnO. Table 1 shows the measurement results.

Comparative Examples 2 and 3 Table 1 shows the measurement results of commercially available antibacterial agents, cuprous oxide (Comparative Example 2) and copper-supported borosilicate glass (Comparative Example 3).

Table 1 Antimicrobial agent Average secondary particle size Antibacterial activity (%) (Μm) E. coli Staphylococcus aureus Example 1 A 0.96 0.125 0.1 Example 2 B 1.28 0.25 0.1 Example 3 C 0.80 0.125 0.1 Example 4 D 0.72 0.05 0.05 Example 5 E 1.91 0.25 0.1 Example 6 F 0.76 0.25 0.125 Example 7 G 0.43 0.25 0.125 Compare Example 1 H 5.14 1.0 or more 1.0 or more Comparative Example 2 Cu ₂ O 1.69 1.0 or more 1.0 or more Comparative Example 3 I 25.3 1.0 0.5 Note: A; Ca _0.95 Zn _0.05 (OH) ₂ B; Ca _0.55 Zn _0.45 (OH) ₂ · mH ₂ O C; Ca _0.98 Cu _0.02 (OH) ₂ D; Ca _0.85 Cu _0.15 (OH) ₂ E; Ca _0.55 Cu _0.45 (OH) _{2 -y Cl y · mH 2 O F} ; Mg 0.97 Cu 0.03 (OH) 2 G; Ca 0.84 Mg 0.10 Zn 0.06 (OH) 2 H; Ca 0.1 Zn 0.9 O y (OH) 2-2y · mH 2 O I: Borosilicate glass-copper antibacterial agent (trade name "Ion Pure", manufactured by Ishizuka Glass Co., Ltd.) Antibacterial property; Minimum growth inhibitory concentration

Examples 8 to 11 To prepare a sheet of soft vinyl chloride, the following compounding ratio: polyvinyl chloride (average degree of polymerization: 1300) 100 parts by weight Dioctyl phthalate 50 parts by weight Ba / Zn composite heat stabilizer (trade name " KV62B-4 ″, manufactured by Kyodo Yakuhin Co., Ltd.) 2 parts by weight Epoxidized soybean oil 2 parts by weight Antibacterial agent 1 part by weight, uniformly mixed, and then melt-kneaded at 170 ° C. for 3 minutes using a roll mill. Then, using a press molding machine, the thickness 1
200kg / cm at 170 ° C for 2 minutes
Molded with pressure of ²

The sheet was sprinkled with blue mold, and the growth of the mold was observed. On the other hand, this sheet
And the time until blackening was measured. Since vinyl chloride blackens when thermally degraded, the longer the time until blackening is, the better the thermal stability is. Table 2 shows the measurement results.

Table 2 Antifungal Agent Thermal Stability Antifungal Evaluation Results (Days of Culture) Time (min) 7 14 21 28 Example 8 J 70 0 0 0 0 Example 9 K 60 0 0 0 0 Example 10 L 60 0 0 0 1 Example 11 M 70 0 0 0 1 Comparative Example 4 No additive 40 Note: J; Ca _0.95 Zn _0.05 (OH) ₂ K; Ca _0.85 Cu _0.15 (OH) ₂ L; Mg _0.97 Cu _0.03 (OH) ₂ M; Ca _0.84 Mg _0.10 Zn _0.06 (OH) ₂ Evaluation method 0: No mold growth was observed. 1; Mold growth was slightly observed. 2; Mold growth was slightly observed. 3; Mold growth was observed moderately. 4: Mold growth was severely observed.

[0034]

According to the present invention, there is provided a novel antimicrobial agent obtained by dissolving copper ion and / or zinc ion in calcium hydroxide or magnesium hydroxide.
The antimicrobial agent of the present invention exerts antimicrobial properties by releasing copper ions and / or zinc ions in an appropriate amount, and does not impair the properties of the resin or rubber when contained in the resin or rubber. Not only these heat resistance,
It has the function of improving weather resistance rather.

Claims (2)

(57) [Claims] 1. A formula ^{_{(1) (M 1 2+)}} 1-x (M 2 2+) x (OH) 2 (1) [ in the formula, the M ₁ ²⁺ is Mg and / or Ca, M ₂ ²⁺ is C
u and / or Zn, and x is 0.0001 ≦ x <
0.9 as the active ingredient. 2. An antimicrobial resin or rubber composition containing 0.001 to 50 parts by weight of the antimicrobial agent according to claim 1 based on 100 parts by weight of the resin or rubber.