JPH0352804A - Antibacterial titanium oxide and preparation thereof - Google Patents

Abstract

PURPOSE:To prepare an antibacterial titanium oxide having excellent antibacterial activity persistence, high hydrophilicity and masking power, no skin irritation property and excellent UV light absorbability by substituting one part or all of ion-exchangeable ions contained in the titanium oxide with antibacterial metal ions. CONSTITUTION:A mixture solution containing four valent titanium and three valent titanium in a molar ratio of 6-720:1 is preferably hydrolyzed and subsequently mixed with an antibacterial metal solution adjusted to a pH of 5-10 to substitute one part or all of ion-exchangeable ions contained in the titanium oxide with antibacterial metal ions, preferably the ions of silver, copper, zinc, mercury, lead, cadmium, chromium and/or thallium to provide an antibacterial titanium oxide which has high ion exchange stability without damaging the fundamental physical properties (hydrophilicity, masking power, stability and UV light absorbability) of the titanium and which has the above-mentioned properties and the antibacterial property imparted by the introduction of the above-mentioned ions.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to antibacterial titanium oxide and a method for producing the same, and more specifically, to antibacterial titanium oxide that is highly safe for the human body and has excellent long-lasting antibacterial effects. It is. [Prior art] Titanium oxide has been widely used as mf-1, a white pigment for plastics, and cosmetics, and its production method is also the titanium hydroxide gel pyrolysis method (Tokuma No. 59-123532).
, titanium alkoxide thermal decomposition l removal (JP-A-60-186)
No. 418) etc. are shown. However, until now, no consideration has been given to the ion exchange properties of titanium oxide, and no attempt has been made to provide new functionality using substituted ions. [Problem to be solved by the invention] Titanium oxide is known as an amphoteric oxide, and its surface dissociates into acid groups and bases depending on the surrounding liquid, exhibiting amphoteric ion exchange properties. However, regular titanium oxide has extremely low exchange capacity, weak ion selectivity, and weak affinity, making it unsafe as an ion exchange material. [Means for solving the problem] The present inventors have discovered that titanium oxide has high hydrophilicity,
It has high hiding power, does not leave any irritation on the skin, does not impair its basic physical properties of excellent UV absorption, and has improved ion exchange stability and imparts antibacterial properties by introducing antibacterial metal ions. As a result of intensive research on the method, we found that antibacterial titanium oxide, which is made by substituting some or all of the ion-exchangeable ions in titanium acid containing both trivalent and tetravalent titanium with antibacterial metal ions, satisfies all of the above conditions. They found that the results were satisfactory and completed the present invention.

That is, according to the present invention, antibacterial titanium oxide, which has excellent long-lasting antibacterial effects, is highly hydrophilic, has high hiding power, is non-irritating to the skin, and has excellent ultraviolet absorption properties, is suitable for cosmetics and the like. Can be provided. The details of the present invention will be specifically explained below. In the present invention, titanium oxide has an ion exchange capacity of 0.3 meq/g from the shin point, which can stably hold a considerable amount of antibacterial metal ions necessary to impart antibacterial properties.
Titanium oxide with the following properties is required. The titanium oxide that satisfies this article I'l: is one that contains both trivalent titanium and tetravalent titanium in its structure. In general, titanium oxide has a structure in which the T14+ ion is surrounded by a slightly irregular octahedron consisting of six U2- ions, and the basic unit is TiO●, where the coordination number of the T144 ion to the 02- ion is roughly 3. It is more established. In this structure, the moisture in the air is strong on the crystal surface.
Coordination polarization occurs on Ti'' ions, then TO, 01 on the surface
``In order to polarize and stabilize the negative charge of the ion, the hydrogen of the adsorbed water molecule is taken away as a proton and two OH groups are created.This becomes an acid group or a hydroxyl group depending on the liquid property, and is the standard for ion exchange capacity. This surface hydroxyl group is influenced by the alpha character and has the drawbacks of weak bonding strength and low ion exchange stability. When a portion of titanium is introduced, there will be an excess of negative tR compared to tetravalent titanium ions, and in order to neutralize it electronically, a large exchange capacity jl (more than 0.3 milliequivalent m/g) of the structure in which cations are ionically bonded A titanium oxide having the following properties is obtained.

The antibacterial titanium oxide used in the present invention is prepared by replacing some or all of the ion-exchangeable ions in the titanium oxide with antibacterial metal ions. As examples of antimicrobial metal ions, mention may be made of ions of silver, copper, zinc, mercury, tin, lead, cadmium, chromium or thallium, preferably daughter ions of copper or zinc.

From the viewpoint of antibacterial properties, it is appropriate that the antibacterial metal ions are contained in titanium oxide in an amount of 1.5 to 10%.

In this specification, % refers to % by weight based on drying at 110°C.

Below are the antibacterial titanium oxides used in the present invention! ! Let me explain about the passing away. Examples of trivalent titanium compounds used in the present invention include titanium trichloride, titanium tribromide, and titanium sulfate (m), but titanium trichloride is preferred because of its safety during the synthesis process and its low cost. preferable. In addition, the four titanium compounds include titanium tetrachloride, titanium tetrabromide, titanium dichloride,
@late titanium l'), li# titanium acid, titanium hydroxide, titanium acetate, titanium brobinate, titanium chloride, late titanium kabrone, titanium benzoate, etc. organic acid salts, isobrobyl titanate, titanium ethoxylate, Titanium alkoxide compounds such as monoacyloxyalkyl titanium, dianloxydiethoxytitanium, and trioquine titanium monohalite can be mentioned, but titanium tetrachloride is preferable from the viewpoint of safety during the synthesis process and reasonable price.

The above jH combination of trivalent titanium and tetravalent titanium (α is 4-field titanium and 3-sake titanium; it is preferable that the molar ratio thereof is 6 to 720. If the amount is less than this range, the titanium oxide itself will evaporate and the range of use will be limited, and if it is more than this range, the effect of Mitsuki Titanium Coating will not be exhibited and only a material with a low exchange capacity will be produced.

The mixed solution of trivalent titanium and tetravalent titanium prepared as described above is hydrolyzed by a conventionally known method to obtain forged titanium oxide particles. Hydrolysis methods include, for example, thermal decomposition in water, spraying under water vapor, etc.
The titanium oxide imitated particles obtained by hydrolysis are then brought into contact with an antibacterial metal rWa to convert the ion-exchangeable ions in the titanium oxide and the antibacterial metal ions. Have it replaced. The contact temperature is 10-70℃,
Preferably at 40-60°C for 3-24 hours, preferably 1
It can be carried out by a batch method or a continuous method (for example, a column method) for 0 to 24 hours. The pH of the above mixed aqueous solution is 5
It is appropriate to adjust it to 10 to 10, preferably 5 to 7.

The PA adjustment is preferable because it can prevent silver oxides and the like from being deposited on the titanium oxide surface and can stably replace antibacterial metals. In addition, each ion in the 7konhe water i1JjFl is normally supplied as a liao. For example, silver ions include silver nitrate, @silver acid, silver perchlorate, l! Silver nitrate, silver diamine nitrate, silver diamine sulfate, etc. Steel ions include steel nitrate (III), copper sulfate, copper perchlorate, copper acetate,
Zinc ion, such as potassium tetracystinate, is zinc nitrate (
II), zinc sulfate, zinc perchlorate, zinc thiocyanate,
Zinc acetate, etc., mercury ions include mercury perchlorate, mercury nitrate, mercury acetate, etc., tin ions include tin sulfate, etc., lead ions include @lead acid, lead nitrate, etc., cadmium ions include cadmium perchlorate,
Chromium ions such as cadmium acid, cadmium nitrate, cadmium acetate, chromium perchlorate, chromium sulfate,
Thallium ions such as chromium nitrate, thallium chlorate, etc.
Thallium sulfate, thallium nitrate, thallium acetate, etc. can be used.

The content of silver ions, etc. in titanium oxide can be appropriately controlled by adjusting the degree of each ion (salt) in the 7-containing solution. For example, when the antibacterial titanium oxide contains silver ions, steel ions, and zinc ions, the silver ion concentration of the mixed aqueous solution is 0.02M/1 to 0.6.
M/l. ii! Ion J degree 0.05M/
I ~1.2M/l, zinc ion 14 degrees 0.07M
/1 to 1.8 M/I, it is possible to obtain antibacterial titanium oxide containing 1.5 to 10% of each of silver ions, steel ions, and zinc ions.

In the present invention, in addition to the above-mentioned mixed aqueous solution 1α, ion exchange can also be performed by using an aqueous solution containing each ion alone and bringing each water, container, and titanium oxide into continuous contact with each other. . The concentration of each ion in each water I'81α can be determined based on the concentration of each ion in the mixed water solution.

After ion exchange, the titanium oxide is thoroughly washed with water and then dried. Drying is carried out at 105°C to 115°C under normal pressure or . 70-90' under pressure (1-30t or r)
It is preferable to use C.

The antibacterial acid monohititanium of the present invention can be used not only in the form of fine particles (powder) but also in various other forms.

For example, a binder may be added to form the product into a honeycomb shape, a bead shape, or a bead shape, or a resin component may be added to form a plastic molded product, cream, ointment, spray, etc.

The antibacterial titanium oxide of the present invention can be used in various fields. For example, chemical products such as makeup and foundation, medical products such as hospital clothes, treatment equipment, hospital interior materials, and wound plasters, clothing products such as sportswear and work clothes, water from cooling towers, and water from metal cutting wells. Preservative/
Suitable for use in the algaecide field, paint field, resin additive field, etc.

〔Effect of the invention〕

The antibacterial titanium oxide of the present invention has an unprecedented long-lasting antibacterial effect, is highly hydrophilic, has high hiding power, is non-irritating to the skin, has excellent ultraviolet absorption, and can be suitably used for various purposes. There is some effect. [Example] The present invention will be explained in more detail below with reference to Examples.

Example l 1.2M/I titanium tetrachloride water iW f&0. 5
Add titanium trichloride aqueous solution to 1 with a Ti''/Ti2+ molar ratio of 7.
20, and the mixed solution 1α was kept at a temperature of 100°C for 3 hours to hydrolyze, then heating was stopped,
It was rinsed and aged overnight in the mother liquor. After aging, 15M/l ammonia water was added dropwise to the titanium oxide suspension L at night to make it neutral, and then filtered and fl! It was washed with water until no chlorine ions were detected during i. j The titanium oxide slurry was adjusted to pH 6.
2 liters! ! L/ta antibacterial metal iiF iff
(0.IM silver nitrate, 1.8M zinc nitrate mixed water, W solution) 11 and maintained at 24° C. while stirring for 24 hours to reach an equilibrium state. After the ion exchange was completed, the titanium oxide phase was filtered and washed with room temperature water or hot water until the excess antibacterial metal ions in the titanium oxide were removed. The obtained titanium oxide was then heated and dried at 110° C. to obtain a sample.

Examples 2 to 12 In Examples 2 to 12, the molar ratio of Ti''/Ti3+ was changed, and in addition to silver nitrate and zinc nitrate as antibacterial metal salts, Cu(N03)t, }Ig(No,)2 , SnS
O4, Pb(NO,〉2, Cd(NOs)z, Cr(N
The same operation as in Example 1 was performed using O2)z and TINI)3. Eleven types of samples were prepared. Detailed data for the preparation of each sample are shown in Table 1. As comparative examples, a sample without titanium trichloride (Comparative Example 1) and a commercially available titanium oxide (Comparative Example 2) that complies with the standards for cosmetic raw materials were also treated in the same manner and used as comparative samples.

Test Example 1 (Antibacterial titanium oxide physical properties) Antibacterial acid 1 titanium obtained in Examples 1 to 12 and Comparative Example 1
, 2, the amount of surface hydroxyl groups, amount of cation exchange, crystal type, crystallite diameter, and color difference were measured. The results are shown in Table 2.

The amount of surface hydroxyl groups is O. 0.1 g of sample was added to OIM/I sodium fluoride solution adjusted to pH 4-5 by adding sodium acetate monoacetate iiia, and after stirring for 1 hour, Jl! The fluorine concentration in the liquid was measured, and the amount of OH'' on the surface was calculated from that amount. Add sample 1 to the solution adjusted to 300mgCaO/l.
After stirring for 2 hours under room rinsing, the residual calcium concentration in the filtrate was measured and determined from the amount. The crystal type was measured using an X-ray diffraction device and was
10) Surface diffraction peak half Il! The crystallite diameter was determined from @. The X-ray diffraction pattern of the sample of Example 1 is shown in Figure 1. The color difference is determined by measuring the color value L. in the CIE color system using a color difference meter.
A and b were measured. Furthermore, the ultraviolet absorption curve of the sample of Example 1 based on barium sulfate is shown in FIG.

Test Example 2 (Antibacterial Test) Antibacterial titanium oxide obtained in Example 1-12 and Comparative Example 1,
The minimum inhibitory concentration (
MIC) was measured and antibacterial properties were evaluated. The test strain was green @@ (Pseudomonas a
eruginosa) +4DP-1 and Esc.
herichia coroni) 1 F O 3301 was used. A plate for sensitivity measurement (Muelle) was prepared by diluting the M solution for inoculation with the number of times of drying of each bacterial species at 10'/n+l to an antibacterial titanium oxide concentration of 2000 pp or less.
rHinton medium> was streaked with a 2 cm strip using a nichrome wire loop, and cultured at 37°C for 18 hours. Judgment is made at the concentration at which growth is inhibited after culturing for a predetermined period of time.
c. The results are shown in Table 2.

Test Example 3 (Test on cosmetics) Using the antibacterial titanium oxide treated in Examples 1 to 12,
Apply O/W type foundation (finishing cosmetics) v4U+ according to the following recipe. ,Ta. Roughly grind the ingredients of ■. Heat and dissolve the ingredients in (2) and adjust the temperature to 80°C. Dissolve the ingredients in (2) by heating, add (2), and disperse uniformly with a homomixer until the temperature reaches 78°C. Add ■ to ■+■ while stirring with an anchor mixer, emulsify, and then disperse uniformly with a homomixer. Start cooling while stirring with an anchor mixer, and at 60'C add the fragrance (■) and cool to 30°C. (Formulation) ■Stearic acid 2.5 parts Brobylene glycol stearate 2.0 parts Cetal
0.3 liquid lanolin
2.0 liquid paraffin
5.0 silicone oil 1.
0 Isobrovir mystiphosphate 3.0 ■Purified water 63.5 Triethanolamine 1.0 Hentonite
1.01,3-butylene glycol
3.0■ Antibacterial titanium oxide
8.0 Hengara 0,7
Yellow iron oxide 0.2 black iron oxide
0.1 ■Fragrance
0.3 The above cosmetics were subjected to a rabbit skin IFi'l intense test and a 1-duration test. Also, comparative example 1
, 2 were also subjected to storage tests. The results are shown in Table 3.

For the rabbit skin irritation test, 50 rabbit specimens were shaved on the dorsal midline the day before application, and 6 application sites with a size of 25 x 25 ms were set. Apply roughly to the dermis in 6 areas!
The stratum corneum was peeled off using a needle to avoid staining. The cosmetic was applied to a cotton cloth, and the cloth was left on the cloth for 24 hours.

After application, the test substance was removed by wiping with absorbent cotton soaked in water. The presence of heat rash and red spots on the skin was determined.

In the storage test, the i used in Test Example 2 was applied to 30g of the cosmetic sample.
Spray 0.3 ml of liquid (lo'/1) and
The mixture was diluted with an α-body medium, and the number of viable bacteria was measured using a 7-disc plate culture method (37°C, 2 days) using a medium for measuring rI1.

Table 3

[Brief explanation of drawings]

The drawings relate to embodiments of the present invention, and FIG. 1 shows x&! of a sample of embodiment I. A diffraction pattern (diffraction angle 2θ
Figure 2 shows the absorption curve of the sample of Example 1 in the ultraviolet/visible wavelength range (wavelength 250-600 rv).

Claims (1)

[Claims] 1. Antibacterial titanium oxide in which some or all of the ion-exchangeable ions in titanium oxide are replaced with antibacterial metal ions. 2. Antibacterial metal ions include silver, copper, zinc, mercury, tin, lead,
The antibacterial titanium oxide according to claim 1, which is an ion of at least one metal selected from the group consisting of cadmium, chromium, and thallium. 3. The antibacterial titanium oxide according to claim 1, wherein the titanium oxide contains both trivalent titanium and tetravalent titanium. 4. The molar ratio of tetravalent titanium to trivalent titanium is 6 to 7.
20 was hydrolyzed, and then the pH was adjusted to 5 to 1.
1. A method for producing antibacterial titanium oxide, which comprises adding an antibacterial metal solution adjusted to zero and replacing it with antibacterial metal ions.