JPH05214262A - Antifungal colored powder - Google Patents

Abstract

PURPOSE:To obtain the title powder excellent in coloring, antifungal and deodorizing properties and reduced in the leaching of metallic ions by coating specified mica particles with a specified amount of fine particles of gold and/or silver. CONSTITUTION:Mica particles of a mean particle diameter of desirably 0.01-25mum surface-coated with a metal oxide (e.g. titanium oxide) of a refractive index of 2.0-3.0 in the form of a layer of a thickness of desirably 10-500nm are coated with 0.001-2wt.%, based on the mica particles, fine particles of gold and/or silver of a particle diameter of desirably 1-500nm.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an antibacterial colored powder blended in polymer products, textiles, paints and the like, and more specifically, it is excellent in coloring property, antibacterial property and deodorizing property, and is capable of eluting metal ions. A small amount of antibacterial colored powder.

[0002]

2. Description of the Related Art Conventionally, as an antibacterial powder composition, there has been proposed a composition in which copper, silver which is an antibacterial metal is supported on zeolite, amorphous aluminosilicic acid or layered silicate. JP-A-62-7748, JP-A-62-70
221 and JP-A-62-84993).

However, each of the above powders has a drawback that the metal is easily eluted since the antibacterial metal is carried on the carrier by the ion exchange method. For this reason, when compounded with polymer products, paints, etc., these products, paints, etc. are deteriorated, and when compounded with fibers, etc., they are in contact with the human body, which poses a safety problem, which is not preferable.

Also, a deposition method of an ion exchange method, for example,
A material in which an antibacterial metal is supported on an inorganic oxide by an electroless plating method is disclosed (Japanese Patent Laid-Open No. 2-268104).
(Japanese Unexamined Patent Publication (Kokai)), this is because it has an antibacterial metal such as silver or copper simply supported on the surface of an inorganic oxide, and is therefore dark and not suitable as a coloring material.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an antibacterial colored powder which is less likely to elute metal ions and is excellent in coloring and antibacterial properties.

[0006]

In view of such circumstances, the inventors of the present invention have conducted diligent research, and as a result, made a specific metal oxide adhere to mica, and further, fine particles of gold and / or silver on the surface thereof. If it is applied, there is no elution of metal ions, and the coloring property,
The present invention has been completed by finding that an antibacterial colored powder having excellent antibacterial properties and deodorizing properties can be obtained.

That is, according to the present invention, the surface has a refractive index of 2.0 to
On a mica coated with a metal oxide of 3.0, 0.001 to 2% by weight of fine particles of gold and / or silver with respect to the mica (hereinafter,
It is intended to provide an antibacterial colored powder characterized by being applied (simply indicated by "%").

The types of mica used in the present invention are
Examples thereof include mascobite, biotite, sericite, and filogobite, and particularly muscovite and sericite are preferable. The average particle size of the mica is preferably 0.01 μm to 25 μm, and the shape is not particularly limited, but is 0.1
.About.20 .mu.m is preferred.

The metal oxide to be deposited on the mica has a refractive index of 2.0 to 3.0. This metal oxide has a refractive index of It means a value measured by a known method of measuring by movement. It is not preferable to use a resin having a refractive index out of the above range because vivid color is not exhibited.

Examples of the metal oxide having such a refractive index include titanium oxide, zinc oxide, zirconium oxide, etc. These are used alone or as a mixture of two or more kinds. The thickness of the metal oxide layer is preferably 10 to 500 nm, and particularly preferably 50 to 150 nm. As a method of forming such a metal oxide layer, for example, a method of forming a predetermined metal oxide layer on the surface of mica is known, that is, mica having a thickness of 0.1 to 25 μm is formed of titanium, zinc or zirconium. The metal oxide is suspended in an aqueous salt solution and subjected to a precipitation reaction with an alkali,
A method of precipitating hydroxide on the surface of mica and, if necessary, performing heat treatment can be mentioned. Further, as the metal oxide-coated mica, a commercially available color pigment can be used. For example, TIM manufactured by Merck Japan KK
IRON (SUPER RED, SUPER BLU
E, SUPER GREEN, SUPER GOLD)
Etc.

The fine particles of gold and / or silver deposited on the metal oxide layer on the mica have a particle size of 1 to 500 nm, and the deposited amount is preferably 0.001 to 2% with respect to the mica. .. If it deviates from this range, vivid color development and low elution property may not be obtained, which is not preferable. Examples of the method of depositing fine particles in such a range include a method of depositing gold and / or silver particles on the surface of the metal oxide layer from an aqueous solution of silver nitrate, chloroauric acid, or the like. For example, as a method for depositing 0.001 to 2.000% of gold or silver fine particles, the metal oxide layer-coated mica is suspended in a chloroaurate solution, a silver nitrate solution or the like, and citric acid or Although a known method of wet reduction with sodium acid or the like can be used, the following method is preferable in order not to impair the effects of the present invention. That is, the concentration of the chloroaurate solution and the silver nitrate solution is 0.01 to 1.0 mol / l, the suspension concentration of the metal oxide layer-coated mica in the solution is 0.1 to 10.0%, and the reduction is The addition amount of citrate as an agent is 0.1 to 10.0 with respect to the gold and silver mole concentrations in the chloroauric acid solution and the silver nitrate solution.
Double amount is desirable, and it is usually used as an aqueous solution of 0.1 to 10%. Further, the reaction temperature is preferably 30 to 90 ° C. Outside this range, the deposited gold and silver particles have a particle size of 1 to 50.
It is outside the range of 0 nm, and the effect of the present invention may be impaired.

[0012]

The antibacterial colored powder of the present invention obtained as described above has an elution amount of gold or / and silver of 10 ppm or less, and CIE1976 (L ^* , a ^* , b ^* ) even perception. L ^* value displayed in color space = 20 to 95, a ^* value = −5 to 3
0, b ^* value = −30 to 20 is exhibited. Further, its antibacterial property and deodorizing effect are superior to those of conventional antibacterial powders. Therefore, when blended in polymer products, textile products, paints, etc., the coloring power, antibacterial properties and safety are higher than conventional products.
It is industrially useful.

[0013]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The measured values in this example and the comparative example were measured by the following method.

1) Particle Size of Adhered Particles On a magnified observation image of 100,000 times by a high resolution scanning electron microscope, the diameter of 500 adhered particles is Fere.
The particle size distribution and the average particle size were determined by measuring with the t diameter.

2) Deposited amount 1 g of the antibacterial colored powder was dissolved in aqua regia, and the ion concentration of silver or gold in the solution was measured by plasma emission spectrometry to determine the deposited amount of silver or gold.

3) Color measurement Spectral color difference meter SZ-Σ8 in accordance with JIS Z8722
0 (manufactured by Nippon Denshoku Industries Co., Ltd.) was used for color measurement. Then, the measurement results are L ^* value, a ^* value, b ^* value (CIE 1
976 (L ^* , a ^* , b ^* ) values displayed in the uniform perceptual color space).

4) Elution amount of adherend: 0.1 g of the antibacterial colored powder was suspended in 100 ml of pure water, and 1
After stirring for 2 hours, solid-liquid separation is performed by centrifugation. The supernatant was filtered using a membrane filter having a pore size of 0.22 μm, the concentration of silver or gold in the filtrate was measured by plasma emission spectrometry, and the elution amount of silver or gold was determined.

Example 1 Blue mica titanium pigment (average particle size = 21.1 μm, TIMIR) in which a TiO ₂ layer having a thickness of 124 nm was coated on the surface of mica.
ON SUPER BLUE, Merck Japan KK
2 g) was suspended in 400 g of ion-exchanged water, and
Add 1.8 ml of a silver nitrate aqueous solution with a concentration of 0.1 mol / l, and add 9
Warmed to 0 ° C. While stirring this mixture, 1%
2.2 g of sodium citrate solution was added dropwise to 90 ° C for 2
After maintaining for a time, it was cooled to room temperature and filtered.
Furthermore, after washing with 2 liters of ion-exchanged water, it was dried at 100 ° C. for 24 hours using a blow dryer to obtain the silver-coated antibacterial colored powder of the present invention. The color of the obtained powder was bluish purple, L ^* = 39.3 a ^* = 12.4 b ^* =-10.3, and it showed pearl luster. It was observed by a high resolution scanning electron microscope (FE-SEM) that ultrafine silver particles having a particle size of 15 to 60 nm (average particle size = 31.5 nm) were deposited on the surface of titanium mica. The amount of silver deposited is
0.7% of base material, silver elution amount 0.18 ppm
Met.

Example 2 Red mica titanium having a 100 nm thick TiO ₂ layer coated on the surface of mica (average particle size = 18.3 μm, TIMIRON)
SUPER RED, manufactured by Merck Japan Ltd. was used. Using 4 g of this powder as a substrate, a silver-coated antibacterial colored powder was obtained by the same procedure as in Example 1. The obtained powder had a reddish purple color, L ^* = 54.0 a ^* = 9.4 b ^* = 5.0, and showed a pearl luster. The particle size distribution of ultrafine silver particles deposited by FE-SEM is 10 to 50 nm.
It was observed that (average particle size = 23.2 nm). The amount of deposited silver was 0.4% with respect to the base material, and the amount of silver eluted was 0.10 ppm.

Example 3 TiO ₂ having a thickness of 124 nm was formed on the surface of the mica used in Example 1.
Layer coated blue mica titanium pigment (average particle size = 21.1
(5 μm) was suspended in 1000 g of an aqueous solution of chloroauric acid having a concentration of 0.01 mol / l, and the suspension was heated to 80 ° C. To this suspension was added 10 g of a 1% citric acid solution heated to 80 ° C. Hold at 80 ° C for 30 minutes and then at 90 ° C for 10 minutes.
Aged for minutes. Then, it was cooled to room temperature, filtered, washed, and then dried at 100 ° C. for 24 hours using a blow dryer to obtain the gold-coated antibacterial colored powder of the present invention. The color of the obtained powder was green, L ^* = 51.2 a ^* = 10.3 b ^* = − 2.9, and showed a pearl luster. The particle size distribution of ultrafine gold particles deposited by FE-SEM is 15 to 60 nm.
It was observed that (average particle size = 32.1 nm). The amount of deposited gold was 0.9% of the substrate, and the amount of gold eluted was 0.13 ppm.

Example 4 5 g of mica having an average particle size of 18.2 μm was suspended in 1000 ml of a 0.2 mol / l zinc sulfate solution, 150 ml of 2N sodium hydroxide solution was added, and then aged at 80 ° C. for 10 minutes. By doing so, a zinc oxide-coated mica was prepared. The same procedure as in Example 1 was performed using 2 g of the powder as a base material to obtain a silver-coated antibacterial colored powder. The color of the obtained powder was gold, and L ^* = 43.9 a ^* = 3.3 b ^* = 10.6. As a result of observation by FE-SEM, the particle size of the deposited silver particles is 10 to 60 nm and the average particle size is 24.7.
was nm. The amount of silver deposited is 0.8% of the base material.
The elution amount was 0.21 ppm. By the same procedure, powders of Examples 5 to 11 were obtained (Table 1). A bright color was observed in all the powders. No agglomeration was observed on the adhered fine particles, and the elution amount of the adherend was 1 in each case.
It was 0 ppm or less.

Comparative Example 1 2 g of mica powder having an average particle size of 18.6 μm was added to 4 parts of ion-exchanged water.
It was suspended in 00 g, to which was added 5.4 ml of 0.1 mol / l silver nitrate aqueous solution, and the mixture was heated to 90 ° C. While stirring this mixed solution, 8 g of a 1% urea solution was dropped, and the mixture was boiled and maintained for 2 hours. Subsequently, it was cooled to room temperature, and after filtration 3 l
It was washed with ion-exchanged water. Then, it was dried at 100 ° C. for 24 hours using a blow dryer to prepare silver-coated mica. The powder obtained was off-white. The particle size of the deposited silver particles was 140 to 750 nm, and many particles of 500 nm or more and agglomerated particles were observed.

Comparative Example 2 A silver-coated zeolite was prepared by the same procedure as in Comparative Example 1 using 2 g of zeolite powder having an average particle size of 3.5 μm as a base material. The powder obtained was off-white. Although it was confirmed by chemical analysis that silver was contained at 2.9%, no silver fine particles were observed on the surface of the zeolite by observation with a high resolution scanning electron microscope.

Comparative Example 3 As a base material, the blue mica titanium pigment used in Example 1 was used, and as a reducing agent, a 1% sodium citrate aqueous solution 6.6.
Using g, a silver particle-coated mica titanium was prepared by the same procedure as in Comparative Example 1. The obtained powder was blue-violet and had a pearlescent luster. The particle size of the deposited silver particles is 130 to 820 nm.
At this point, particles of 500 nm or more and aggregated particles were observed.

Table 1 shows the data of the above antibacterial colored powder.

[0026]

[Table 1]

Test Example 1 The following antibacterial test 1 was carried out using the antibacterial colored powders obtained in Examples 1 to 4 as samples. As a comparative example, in the case of no addition, the same test was conducted with 10 μg of silver powder and 1 mg of mica titanium having a titanium layer thickness of 140 nm. The results are shown in Table 2.

1) Antibacterial test 1 As a test strain, Escherichia coli (Esheric)
hia coli IFO13111), Proteus
Bulgaris (Proteus vulgaris IF
O3167), Pseudomonas aeruginosa (Pse
udomanas aeruginosa IFO13
275), Staphylococcus aureus (Stap)
hylococcus aureus IFO1327
6), Streptococcus mutans (Strep
tococcus mutans ATCC25175)
Was mixed with 1 mg of the antibacterial colored powder of the present invention in 1 ml of sterilized water. Then, it was diluted with sterile physiological saline and inoculated on SCD agar medium (Daigo). The number of growing colonies after culturing at 37 ° C. for 2 days was measured to determine the viable cell count (CFU / ml).

[0029]

[Table 2]

As shown in Table 2 above, the products of the present invention showed remarkable bactericidal activity against all strains.

Test Example 2 The following antibacterial property test 2 was conducted using the antibacterial colored powders obtained in Examples 1 to 4 as samples. As a comparative example, the same test was carried out with no addition, and with the powders obtained in Comparative Examples 1 to 3 and 5 μg of silver nitrate. The results are shown in Table 3.
Shown in.

2) Bactericidal test 2 Bacteria in saliva collected from adult males were used as test strains and mixed with 1 mg of the antibacterial colored powder of the present invention and 1 ml of sterilized water. Then, it was diluted with sterile physiological saline and inoculated on SCD agar medium. The number of growing colonies after culturing at 37 ° C. for 2 days was measured to determine the viable cell count (CFU / ml).

[0033]

[Table 3]

As shown in Table 3, the antibacterial colored powder of the present invention showed remarkable bactericidal properties against bacteria in saliva.

Test Example 3 Using the antibacterial colored powders obtained in Examples 1 to 4, the following deodorizing power test was conducted. As a comparative example, the same test was performed for the case of no addition and for the powder, titanium mica, and activated carbon obtained in Comparative Examples 1 to 3. The results are shown in Table 4.

3) Deodorizing Power Test 0.1 mg of the antibacterial colored powder of the present invention was weighed in a 10 ml gas chloride vial, 1 ml of ion-exchanged water was added, and the vial was tightly stoppered. 2 μl of a benzene solution of methyl mercaptan having a concentration of 100 μg / ml was injected into this. 37
After incubation at 5 ° C for 5 minutes, the concentration of methyl mercaptan contained in the headspace gas was measured by gas chromatography.

[0037]

[Table 4]

As shown in Table 4, the product of the present invention had a remarkable deodorizing ability.

Claims (5)

[Claims] 1. Fine particles of gold and / or silver are deposited on the surface of a mica having a surface thereof coated with a metal oxide having a refractive index of 2.0 to 3.0 in an amount of 0.001 to 2% by weight. An antibacterial colored powder characterized by the following. 2. The antibacterial colored powder according to claim 1, wherein the metal oxide is one kind or two or more kinds selected from titanium oxide, zinc oxide and zirconium oxide. 3. The antibacterial colored powder according to claim 1, wherein the mica has an average particle diameter of 0.01 to 25 μm. 4. The thickness of the metal oxide layer is 10 to 500 nm.
The antibacterial colored powder according to claim 1, which is 5. The particle size of fine particles of gold and / or silver is 1-5.
The antibacterial colored powder according to claim 1, which has a thickness of 00 nm.