JP3353446B2 - Antibacterial sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to baths, toiletries,
The present invention relates to a sheet having a bactericidal or antibacterial property in a living environment such as a room, and particularly to an antibacterial sheet without using a chemical for bactericidal or antibacterial.

[0002]

2. Description of the Related Art Conventionally, various attempts have been made to provide a particularly clean environment for the purpose of improving a living environment such as a home and a building. For example, for housing equipment, as a means of imparting sterilization or antibacterial properties, there are various methods such as an ultraviolet irradiation method using an ultraviolet lamp, an ozone oxidation method, a cleaning method using a sodium hypochlorite solution, and the like.
Each is selected according to the purpose. Furniture and merchandise, especially those requiring sterilization or antibacterial properties for hygiene, in the case of plastic sheets and resin molded products, by kneading antibacterial agents such as chemicals into the resin, or by coating the surface, Has bactericidal or antibacterial properties. Also, silver zeolites and metal materials are used as antibacterial agents, and are kneaded into resin or applied to the surface to similarly impart sterilization or antibacterial properties to articles.

[0003]

However, the ultraviolet irradiation method and the ozone oxidation method require an apparatus for generating ultraviolet light and ozone, and also cause discoloration and deterioration of the resin surface of an article to be sterilized. When used for a long time, there is a problem that the effect on the human body cannot be ignored.

Also, an antibacterial agent is kneaded in the resin in advance,
When it is used as a material, only the antibacterial agent bleed out to the surface of the article is effective, so the antibacterial agent present inside the resin cannot exert its effect, but also the antibacterial agent exposed on the surface In order to increase the number of agents, it is necessary to mix a large amount.Addition of an antibacterial agent causes a decrease in physical properties such as mechanical strength, weather resistance, and durability of the resin. We needed to consider.

In the case of applying to an article, it is necessary to expose the surface of the antibacterial agent at a high concentration in order to effectively maintain and exhibit the sterilizing and antibacterial effects of the antibacterial agent.
As described above, it was necessary to consider the effects on the human body, such as the safety of drugs. Furthermore, even when an inorganic substance other than a chemical is kneaded into a resin similarly as an antibacterial agent and coated, addition of the resin to the resin causes a decrease in physical properties, and the coating also has a problem of peeling during use of the article.

Accordingly, an object of the present invention is to provide an antibacterial sheet which is highly safe against an external environment, especially a human body, and which can maintain antibacterial properties for a long period of time.

[0007]

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is a metal film or a metal oxide film on at least one surface of a substrate film.
An insulating thin film layer consisting of
It becomes Te, and it is an antibacterial sheet according to claim obtained by forming a large number of small holes penetrating in the substrate film and the insulating thin film layer.

[0008]

[0009]

[0010]

The antibacterial sheet of the present invention has a structure in which gold
Insulating thin film layer consisting of oxides or carbides, antibacterial metals
By laminating the thin film layers sequentially, and by forming a large number of small holes in the base film and the insulating thin film layer, metal ions released from the metal thin film layer formed in the insulating thin film layer are formed in the insulating thin film layer. It is adsorbed and stored in the porous part, and gradually elutes or oozes through the pores of the base film to the surface of the base film, thereby exhibiting antibacterial properties. Since the metal is gradually eluted through the small holes of the base film to provide antibacterial properties, stable antibacterial properties can be maintained for a long time with safety.

Further, the antibacterial sheet of the present invention has an anchor function of further increasing the adhesion between the base film and the antibacterial metal thin film layer by providing an insulating thin film layer made of a metal oxide on the base film. When forming the small holes, the small holes can be easily formed by utilizing the charging at the time of forming the thin film.

Further, the antibacterial sheet of the present invention may contain silver or / and / or silver.
And antibacterial metal thin film layer such as copper and bacteria
Antibacterial properties can be exhibited by the effect of suppressing proliferation .

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing one embodiment of the antibacterial sheet of the present invention, FIG. 2 is a schematic diagram illustrating an example of an apparatus for producing the antibacterial sheet of the present invention, and FIG. FIG. 3 is a schematic diagram illustrating formation of an insulating thin film layer and porosity on a base film of a conductive sheet.

The antibacterial sheet 1 of the present invention shown in FIG. 1 comprises a base film 2 on which an insulating thin film layer 3 and a metal thin film layer 4 are sequentially formed. Many small holes 5 penetrating both layers are formed.

The base film 2 is mainly in the form of a film or sheet made of various natural resins and synthetic polymer resins, but is not particularly limited thereto. Specifically, polyethylene, polypropylene, polyvinyl alcohol, polyethylene terephthalate, polyvinyl chloride,
Uses general-purpose plastics such as polyvinylidene fluoride, polyamide, polyimide, polycarbonate, cellulose, methylcellulose, methylethylcellulose, carboxymethylcellulose, and engineering plastics such as polyetheretherketone, polyethersphone, polyetheretherimide, and polyphenylene sulfide. can do. Although the layer thickness of the base film 2 is not particularly limited, it is appropriately selected and designed from a film shape of about 6 μm to 1 mm to a sheet shape according to the use and the like. In particular, it is possible to use a roll-up type continuous vapor deposition apparatus by making it long so that it can be formed continuously.

The insulating thin film layer 3 is made of magnesium (M
g), a compound thin film made of a compound of a metal oxide such as aluminum (Al), silicon (Si), zirconium (Zr), titanium (Ti), zinc (Zn), or a carbide, and having the above characteristics. It is not particularly limited. Considering the processability of forming the small holes together with the base film 2 by using the charging of the base film described below, the surface resistance value of the insulating film layer is 10 ¹⁵ (Ω / □).
It is preferable that it is above.

The thickness of the insulating thin film layer 3 is 2 to 500 nm.
And preferably 10 to 200 nm. 5
When the thickness is larger than 00 nm, the thin film is cracked and the thin film falls off the surface of the base film 2, which is not preferable. If the thickness is less than 2 nm, poor adhesion to the metal thin film layer and a problem of small hole processing with the base film 2 utilizing the chargeability of the insulating thin film described below will occur. As a method for forming the insulating thin film layer 3, a known dry process such as a vacuum deposition method, a sputtering method, a plasma deposition method, and an ion plating method can be used. In particular, in the case of the vacuum vapor deposition method, a large-scale processing can be performed continuously at high speed and at a low cost by using the long base film 2.

The metal thin film layer 4 is made of silver (Ag), copper (C
u), antibacterial from metals such as titanium (Ti), zinc (Zn), zirconium (Zr), gold (Au), iron (Fe), tin (Sn), oxides or other compounds thereof The material is selected, and any metal material having antibacterial properties other than those listed above can be used.
The thickness of the metal thin film layer 4 is in the range of 5 to 500 nm,
If the thickness is smaller than 500 nm, the antibacterial properties are insufficient, and 500
If the thickness is more than 10 nm, there is a problem that the insulating film 3 or the base film 2 may fall off. Preferably it is in the range of 5-200 nm.

The method for forming the metal thin film layer 4 is the same as the method for forming the insulating thin film layer 3 described above, and utilizes a known dry process such as vacuum deposition, sputtering, plasma deposition, or ion plating. be able to. Similarly, according to the vacuum deposition method, a long base film 2
It is possible to mass-process continuously at high speed and at low cost.

Next, according to the method of the present invention for forming a large number of small holes through the base film 2 on which the insulating thin film layer 3 is formed, the film is wound in a vacuum vessel 20 by the vapor deposition device 6 shown in FIG. The evaporation source 22 is heated by the electron beam 23 on the film base material 2 supplied from the take-up roll 25 by the electron beam heating method.
It is evaporated and cooled by the metal roll 21 to continuously form the insulating thin film layer 3, and is wound up by the winding roll 27 via the guide roll 26. Here, small holes are formed in the base film 2 and the insulating thin film layer 3 by utilizing the arc discharge 24 generated when the metal roll 21 is peeled off. That is, a thin film of an insulating thin film material is formed on the base film 2 by an electron beam method.
Are charged by reflected electrons or secondary electrons generated by the irradiation of the electron beam 23, and at the same time, the metal roll 2 is charged.
A reverse potential is induced on the surface of the base film 2 that is in contact with 1, and when the base film 2 separates from the metal roll 21, an arc discharge 24 is generated. The holes can be easily formed.

Further, the base film 2 and the insulating thin film layer 3
The number and diameter of the small holes 5 formed in
By adjusting various parameters of the plasma discharge unit 28 used for removing the charge of the film substrate 2 to be deposited, the charge can be controlled, that is, the number and diameter of the small holes can be controlled. The number and size of the generated small holes vary depending on the type and thickness of the film substrate 2 used and the type and thickness of the insulating thin film layer 3. It can be controlled by changing the supply power 29 supplied to the section 28, the composition of the plasma generating gas 30, and the discharge pressure.

The method for producing the small holes formed in the base film 2 and the insulating thin film layer 3 may be a laser method, a hot-needle penetration method, a diamond roll method, or the like, in addition to the above-described arc discharge by charging. it can.

In the present invention, the opening diameter of the small hole 5 formed through the base film 2 and the insulating thin film layer 3 is 0.1 mm.
About 1 to several tens μm is preferable. When the thickness is 0.1 μm or less, the elution of metal ions from the metal thin film layer 4 decreases, and antibacterial properties become insufficient. When the thickness exceeds tens of μm, the elution rate of metal ions from the metal thin film layer 4 increases, Although it has excellent antibacterial properties, it has a problem that its antibacterial effect decreases with time. The number of holes is based on the hole density, and the hole density is 10 to 100 holes / cm ² . If the number is less than 10, the antibacterial properties are insufficient, and if it exceeds 100, the mechanical strength of the base film 2 is reduced.

Although not shown in the drawings, the non-laminated surface side of the base film 2 is coated with a resin containing various surfactants, coloring pigments and fillers, and visible information such as characters and pictures and designs are known as print layers. It can be arbitrarily provided by a gravure printing method, an offset printing method, or a silk screen printing method.

A more specific embodiment will be described. (Embodiment 1) A manufacturing apparatus 7 shown in FIG. 2 uses a vacuum apparatus 9 to form an insulating thin film on a biaxially oriented polyester having a layer thickness of 12 μm as a long base film 2 supplied from a winding roll 11. The layer 3 is made of magnesium oxide having a layer thickness of 50 μm, and is heated by an electron beam 13 from an electron gun 12 by an electron beam 13, and is continuously formed on a metal roll 15. Sent to Next, a silver thin film having a thickness of 20 nm was formed as a metal thin film layer 4 by a DC sputtering method on a metal roll 17 by a sputtering unit 18 and wound around a winding roll 19. The small holes 5 are formed by supplying an argon / oxygen (80/20 wt%) gas to the plasma discharge unit 10 shown in the vacuum apparatus 9 of the manufacturing apparatus 7 in FIG. Then, small holes of 0.7 μm were continuously formed in 50 to 70 pieces / cm ² .

Comparative Example 1 A silver thin film was formed on the base film of Example 1 (biaxially oriented polyester having a layer thickness of 12 μm)
It was produced continuously by the C sputtering method. Comparative Example 2 A vinyl chloride-vinyl acetate copolymer resin containing 10% by weight of silver zeolite was coated on a polyester film having a layer thickness of 12 μm to a layer thickness of 3 μm by a gravure coating method to prepare a composite film.

Example 2 In the same manner as in Example 1, a vacuum device was used to form a base film 2 on a transparent polypropylene sheet having a thickness of 0.8 mm and aluminum oxide as an insulating thin film layer 3 to a thickness of 30 nm. Then, aluminum oxide was formed to a thickness of 40 nm as a metal thin film layer 4 by DC sputtering. (Example 3) As in Example 1, silicon oxide was formed to a thickness of 60 nm as the insulating thin film layer 3, and copper was formed to a thickness of 100 nm as the metal thin film layer 4.

The antibacterial properties of the antibacterial sheets of Examples and Comparative Examples obtained as described above were evaluated by the following methods. <Test 1> The antibacterial sheets obtained from Examples 1 to 3 and Comparative Examples 1 and ² were cut out by 100 cm ² to prepare test pieces. The surface of the base film 2 on the non-laminated surface of these test pieces and the surface coated with the silver zeolite of Comparative Example 2 were aseptically sterilized with 100 ml of sterilized distilled water to which 0.1% of a surfactant (TWEEN80) was added. I washed it. The number of bacteria in this washing solution was measured by a pour method using an ordinary agar medium. Table 1 shows the results.

[0029]

[Table 1]

<Test 2> Each test piece 100
cm ² and Staphylococcus aureus (Staphyloc
occus aureus) 100cm ²
The coating is ¹⁰⁵ per, the test piece was measured number of bacteria after standing 24 hours at room and evaluated antimicrobial properties after one month after the year in the same manner.

[0031]

[Table 2]

From the test results, those of Examples 1 to 3 exhibited good antibacterial properties at the beginning of the test, after one month, and after one year, and the antibacterial effect of the antibacterial sheet of the present invention was low. It is effective for a long time. Moreover, although the antibacterial properties of Comparative Examples 1 and 2 show an initial antibacterial property, the antibacterial properties decrease with time.

[0033]

As described above, according to the present invention, an insulating thin film layer and a metal thin film layer are sequentially laminated on a base film,
And since it is an antibacterial sheet in which many small holes are formed in the base film and the insulating thin film, metal ions released from the metal thin film layer formed on the insulating thin film layer are formed in the insulating thin film layer. It is adsorbed and stored in a large number of holes, and gradually elutes or oozes out to the surface of the base film through the holes of the base film, thereby exhibiting antibacterial properties. In addition, the metal gradually elutes through the small holes of the base film and imparts antibacterial properties to the sheet. Unlike the one that is embedded, it is possible to maintain stable antibacterial properties for a long time with safety.

Further, since the insulating thin film and the metal thin film layer can be formed by an inexpensive dry process, and particularly, the small holes provided in the base film and the insulating thin film can be continuously formed in the vapor deposition step, the antibacterial sheet can be formed. Can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the antibacterial sheet of the present invention.

FIG. 2 is a schematic diagram illustrating an example of an antibacterial sheet manufacturing apparatus of the present invention.

FIG. 3 is a schematic view of a perforation apparatus for explaining formation of an insulating thin film layer on a base film of the antibacterial sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antibacterial sheet 2 Base film 3 Insulating metal layer 4 Metal thin film layer 5 Small hole 6 Evaporation apparatus 7 Manufacturing apparatus 9, 20 Vacuum apparatus 10, 28 Plasma discharge part 11, 25 Unwind roll 19, 27 Take-up roll 12 Electron gun 13,23 Electron beam 14,22 Evaporation source 15,17,21 Metal roll 16,26 Guide roll 18 Sputtering unit 24 Arc discharge 29 Supply power 30 Gas for plasma generation

Claims (1)

(57) [Claims] 1. A method according to claim 1, wherein at least one surface of the base film is coated with a metal acid.
Insulating thin film layer made of oxide or carbide, antibacterial metal thin film
An antibacterial sheet comprising a plurality of layers sequentially laminated, and a large number of small holes penetrating the base film and the insulating thin film layer.