JP2716644B2 - Production method of bioactivity inhibitor - 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 a bioactivity inhibitor, and more particularly to a bioactivity inhibitor capable of sterilizing or inhibiting the activity of various fungi such as Escherichia coli and water moss in a water tank. Related to the production method.

[0002]

2. Description of the Related Art Conventionally, methods for sterilizing microorganisms or suppressing their activity include, for example, heat sterilization, ultraviolet sterilization, cell membrane destruction by ultrasonic waves, sterilization using electricity or gas, sterilization using toxic substances, Various methods are used in a wide range of fields, such as a high magnetic field sterilization method and a drug sterilization method using a halogen-based or surfactant-based drug.

[0003] However, such methods of sterilizing microorganisms or suppressing their activity all require relatively large-scale equipment, and the emphasis is placed on immediate effect, so that the products themselves to which bacteria have adhered at the same time as sterilization are used. Often accompanied by the risk of destruction or damage.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and simply by immersing in an aqueous system whose biological activity is to be suppressed without requiring a complicated apparatus. Another object of the present invention is to provide a method for producing a bioactivity inhibitor which can sterilize or effectively suppress the biological activity thereof.

[0005]

Means for Solving the Problems The present inventor has proposed an optical semiconductor,
For example, when a titania (TiO ₂ ) powder is irradiated with ultraviolet light in the presence of oxygen, it exhibits a property of decomposing a stable hydrocarbon, and the presence of water in a photoelectrochemical cell in which a metal is supported on the titania powder. Focusing on the fact that when exposed to ultraviolet light underneath, it has a strong oxidizing power and has the property of oxidizing water to generate oxygen, and the characteristics of such a photoelectrochemical cell are killed by microorganisms or their activity is suppressed. As a result of intensive research for use in the field, the coating formed from the mixture of fluorochemical resin powder in the photoelectrochemical cell in which the metal is supported on titania particles, when immersed in an aqueous system, can remove various fungi, moss and other microorganisms. The present inventors have found that they exhibit properties of sterilizing or inhibiting the activity thereof, that they are hard to adhere to contaminants such as oil, and that they have excellent hydrophobicity and durability.

Namely, the present invention provides bioactive suppressor, characterized in that in a mixture of photoelectrochemical cell and the fluororesin powder carrying a metal on the optical semiconductor particles sprayed on the substrate surface to form a film Regarding the manufacturing method.

[0007]

An ultraviolet light (wavelength 4) is applied to a film (or a substrate having the film) made of a mixture of an optical semiconductor fine particle, for example, a photoelectrochemical cell having a metal supported on titania and a fluororesin powder.
(Not more than 00 nm), electrons in the valence band of the titania are excited to the conduction band, and holes are generated in the valence band. These holes move to the surface along the potential gradient generated near the titania surface. Since these holes have a strong oxidizing power substantially by the energy of the band gap, if water is present on the titania surface due to the oxidizing power, the water is oxidized to generate oxygen. Therefore, when this coating or substrate is immersed in an aqueous system, the active oxygen can suppress the microbial activity or kill the microbe itself. Note that the electrons excited in the conduction band move to the metal supported on the titania, which is a counter electrode, and reduce water to generate hydrogen.

In the present invention, the optical semiconductor includes, for example, titania, strontium titanate, potassium niobate, etc., of which titania is preferably used. As the titania (tetravalent), those having a rutile type crystal structure can be used, but the anatase type is preferably used because it has a large surface area and is more active. In both the photosemiconductor ceramic and the supported metal, the function of suppressing the biological activity is extremely related to the surface area. Therefore, in principle, the thinner the better, the better. The particle size of the titania particles is preferably from 0.1 to 60 μm, particularly preferably from 1.0 to 10 μm.
μm is preferred. Examples of the metal supported on the titania particles include conductive metals having low toxicity such as silver (Ag), nickel (Ni), and platinum (Pt).
For example, Ag is suitably used as a bioactivity inhibitor for medical use, and Ni is suitably used as a bioactivity inhibitor for general industry for the purpose of suppressing the generation of moss.

In the present invention, as a method of supporting a metal on titania particles, for example, a physical method using centrifugal force, an electrolytic plating method, a composite coating forming method using ultrafine metal powder, a thermal spraying method, a metal spraying method, Known methods such as a method of dipping in a salt solution, a method of dipping in an organic metal such as an alkoxide, and a heat treatment can be applied, and are not particularly limited. Further, the amount of metal carried is preferably 0.5 to 30% by weight,
Particularly, 5 to 15% is preferable.

[0010] The particle diameter of the fluororesin powder mixed with the photoelectrochemical cell in which titania particles carry a metal is not particularly limited as long as a uniform mixture can be formed. The mixing ratio of the fluororesin powder to the titania photoelectrochemical cell is, for example, 5 to 90 % by weight, preferably 10 to 2%.
0%. In the present invention, as a method of heating a mixture of a photoelectrochemical cell in which titania fine particles carry a metal and a fluororesin powder (hereinafter, sometimes referred to as a raw material mixture) to a temperature equal to or higher than the melting point of the fluororesin, and forming a film. Is
Known film forming methods, for example, an inflation method, a calender roll method, a casting method and the like can be used. The thickness of the coating can be appropriately selected depending on the application.

In the present invention, in order to form a film of the raw material mixture on the substrate, a method of spraying the raw material mixture on the substrate is preferable. Thermal spraying can be performed using a spray gun, but it is desirable to use a low-temperature thermal spraying apparatus in order to minimize deterioration of the fluororesin in the raw material. As an apparatus of this kind, for example, an air curtain is formed by an air jet flow on an outer periphery of a gas frame formed at a tip portion of a gas nozzle, a spray material is supplied from outside the air curtain, and heat of the gas frame is indirectly transmitted. The sprayed material is softened by being applied to the sprayed material, and the softened sprayed material is sprayed onto the surface of the coated base material. To form a strong bonding film. As such a low-temperature spray gun, for example, French Society
te Nouvelle deMetallisati
A JET-PMR type gun manufactured by on Industries.

The substrate is not particularly limited as long as it can form a film of the raw material mixture on its surface. Examples of the substrate include sheets, films, cylinders, and cylinders made of various polymer materials.
Examples include molded articles such as ring honeycombs, boards, papers, cloths, nonwoven fabrics, and fiber laminates (webs). The fluororesin in the present invention imparts film forming properties to the raw material mixture, improves water repellency and hydrophobicity of the film or the base material, and also has stain resistance, for example, suppresses adhesion of contaminants such as oil, and has durability. Work to improve.

The bioactivity inhibitor produced according to the present invention can be used alone or in combination with other materials,
By immersing or contacting in an aqueous system in which sterilization or biological activity is to be suppressed, the activity of microorganisms and the like existing in the system can be suppressed. The field of application of the bioactivity inhibitor of the present invention includes, for example, the following fields.
That is, in the medical field, for example, disinfection of instruments that cannot be sterilized at high temperature, disinfection of disinfectants, application to disinfection of Staphylococcus aureus, etc., in the field of food industry, for example, maintaining freshness of tofu and the like, various water tanks Purification, sterilization of food storage containers, application to rot prevention of edible oil, etc., in the field of biochemicals, for example, application to aseptic plant raising, hydroponic cultivation, etc., in the general industrial field, for example, cutting oil It can be used as a coating for preventing corrosion of water, preventing the occurrence of algae in water intake and drainage, preventing water-related pollution, and suppressing plant activity in all fields such as marine development and general households. By applying the bioactivity inhibitor produced according to the present invention to the ship bottom,
It is possible to prevent shellfish and algae from adhering to the ship bottom.

[0014]

Next, the present invention will be described in more detail with reference to examples. Example 1 A composite film forming method was applied to 5 to 15 μm titania particles.
Ni is supported at 10% by weight to form a photoelectrochemical cell, and 90% by weight of tetrafluoroethylene powder (trade name: Teflon: a trademark of DuPont) having a particle size of 1.0 μm or less is mixed into the photoelectrochemical cell. The mixture was prepared using a SNMI JE
Using a T-PMR type gun, a coating is formed directly on a polyester non-woven fabric at about 3000 ° C. without using a binder so that the film pressure becomes 50 μm, thereby forming an optical semiconductor cloth of the present invention. did. Cut this one
Two 3.8 cm × 17.8 cm optical semiconductor cloths were obtained.

Next, 1 mg of ammoniacal nitrogen as nutrients was placed in a 7-liter water tank (manufactured by Nippon Water Tank Co., Ltd.).
/ Liter, phosphorus 0.1mg / liter, algal breeding species 5m
1 was added to tap water, and the two optical semiconductor cloths were immersed, and the occurrence of water moss was observed. The water temperature is 1
The temperature was kept at 9 ° C. ± 1 ° C., and observation was continued by adding an amount of water corresponding to the reduced water. The aquarium continued to be inflated with an air diffuser. As a result, no moss was generated even after 22 days from the start of observation. On the 22nd day after the start of the observation, one of the optical semiconductor cloth was removed, and 5 more algal breeding species were obtained.
Further observation was continued after adding ml, and no generation of water moss was observed even after 18 days had elapsed. On the 40th day after the start of the observation, the remaining optical semiconductor cloth was taken out, and the observation was further continued. No generation of moss was observed even after 44 days from the start of the observation.

In this example, it was found that the algae-suppressing effect was maintained even after all of the optical semiconductor cloth was extracted. Comparative Example 1 The occurrence of water moss was observed in the same manner as in Example 1 except that the optical semiconductor cloth was not immersed. On the 6th day after the start of the observation, thin green algae were generated on the diffuser tube, wall surface, and the like. On the 8th day after the start of observation, the green color became deeper. On the 22nd day after the start of the observation, the water color changed to brown due to the death of the algae.

Table 1 shows the changes in nutrient concentrations in water in Example 1 and Comparative Example 1.

[0018]

[Table 1] Note 1) All of the added NH ₃ -N changed to nitrate nitrogen on the sixth day after the start of the test.

Note 2) On the 12th day after the start of the test, all the nitrogen of Comparative Example 1 was taken into the algae. Table 1 shows that Example 1 in which the optical semiconductor cloth was immersed effectively suppressed the generation of algae. Example 2 The photosemiconductor cloth prepared in Example 1 was cut into a piece of 5 mm × 5 mm, and an Escherichia coli culture solution adjusted to be about 10 ⁶ pieces / ml was uniformly inoculated into the cut piece, and then inoculated at 20 to 25 ° C. (room temperature). ), And preserved while irradiating with light of 750 to 800 lux (commercially available 40 w fluorescent lamp). After a certain period of time, surviving bacteria on the test piece were washed out with 10 ml of SCDLP (manufactured by Nippon Pharmaceutical Co.).
The number of viable bacteria was measured for this washed-out liquid by a pour plate method (35 ° C. for 2 days) using a culture medium for measuring the number of bacteria, and converted to the number of viable bacteria per test piece. 1
0 ⁵ was the number of bacteria after after 0.5 hours was 10 or less.

Comparative Example 2 The same bacterial solution as that inoculated to the test piece in Example 2 was dispensed into the same amount of petri dish, stored in the same manner, and subjected to the same test. The number of 10 ⁵ bacteria was 8.7 × 10 ⁵ after 1 hour, 1.1 × 10 ⁶ after 6 hours,
After 24 hours, the number was 1.1 × 10 ⁶ .

The results of Example 2 and Comparative Example 2 are shown in Table 2.

[0022]

[Table 2] In Example 2, in order to correct the sterilizing function of Ag carried on the titania particles in the process of manufacturing the optical semiconductor cloth, the sterilizing function of the substrate electrolessly plated with Ag was examined in the same manner as in Example 2. After a lapse of about 30 minutes, no definitive effect was observed.

From the above, it can be seen that the photosemiconductor cloth of Example 2 has a remarkable bactericidal action against Escherichia coli. Example 3 The raw material mixture used in Example 1 was supplied to a melt extruder having a slit nozzle and extruded into a sheet at about 300 ° C.
A sheet having a thickness of about 1 mm was obtained. This sheet was cut into test pieces having the same dimensions as in Example 1 and tested in the same manner as in Example 1. As a result, similar test results were obtained.

[0024]

According to the invention of claim 1, wherein, according to the present invention, the molded with a mixture of photoelectrochemical cell and the fluororesin powder metal to titania is an optical semiconductor microparticles carrying
By immersing or contacting the substrate having the membrane in the water to be treated, an excellent bactericidal action and a biological activity suppressing action can be obtained, so that it can be usefully used as a biological activity suppressing material in various industries. Claim 2 of the present application
According to the invention, as the thermal spraying device, the outer periphery of the gas frame
Forming an air curtain, and indirectly through the air curtain
By using a thermal spraying device that heats the thermal spray material
Degradation of fluororesin in the material can be minimized
You.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B32B 27/30 B32B 27/30 D D06M 15/256 D06M 15/256 D21H 19/10 D21H 1/34 Z (72) Inventor Tsukasa Sakurada 1391-3 Ogiwara, Agematsu-cho, Kiso-gun, Nagano Pref. Shinshu Ceramics Co., Ltd. (56) References JP-A-63-278954 (JP, A) JP-A-61-76160 (JP, A) JP-A-62-66861 (JP, A) JP-A-3-8448 (JP, A) JP-A-6-254139 (JP, A) JP-A-58-125602 (JP, A)

Claims (2)

(57) [Claims] 1. A method for producing a bioactivity inhibitor, comprising spraying a mixture of a photoelectrochemical cell in which a metal is supported on fine particles of an optical semiconductor and a fluororesin powder onto the surface of a substrate to form a coating. 2. The photoelectrochemical cell and a fluororesin powder.
Gas spray as a device for spraying a mixture of
An air curtain is formed on the outer periphery of the
To use a thermal spraying device to indirectly heat the thermal spray material
The method for producing a biological activity inhibitor according to claim 1.