JPS6121102B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultraviolet sterilizer that can simultaneously wash and sterilize dirt, bacteria, etc. adhering to the surface of a sheet.

Generally, there are two types of sterilization methods for packaging materials: chemical sterilization methods and physical sterilization methods.

Chemical sterilization methods include ethylene oxide gas sterilization,
Possible methods include propylene oxide gas sterilization and hydrogen peroxide sterilization.

Ethylene oxide gas sterilization and propylene oxide gas sterilization are effective sterilization methods because they are gas sterilizations and can sterilize at the final stage of packaging material production.

However, since both ethylene oxide gas and propylene oxide gas are toxic gases, their residue in packaging materials often becomes a problem.

Hydrogen peroxide sterilization is a very effective method for sterilizing packaging materials, but in recent years its carcinogenicity has been pointed out, making it difficult to use it as before.

Furthermore, hydrogen peroxide has a bleaching effect, which is not good for the health of workers.

On the other hand, physical sterilization methods include τ ray sterilization and ultraviolet sterilization, which are very effective sterilization methods.

In particular, since τ rays can penetrate plastic packaging materials, it has the advantage of being able to sterilize in the final step of packaging material production, similar to gas sterilization.

However, even with this method, deterioration in physical properties such as a decrease in heat sealing strength and yellowing of the plastic film after irradiation with τ rays is observed.

Next, the ultraviolet sterilization method is safe because the ultraviolet rays themselves have less of an effect on the human body than gamma and beta rays. Moreover, it has the advantage of being easy to install.

However, ultraviolet rays only have a sterilizing effect on the surface, making complete sterilization difficult.

As mentioned above, all sterilization methods have advantages and disadvantages, and the current situation is that no one is perfect.

The present invention was invented in view of the above-mentioned current situation, and includes an ultraviolet sterilizer installed in a sterilization treatment tank in which the sheet-like material passes through an ultraviolet-transparent solution, and the sheet-like material is irradiated with ultraviolet light. The sheet material is constructed so that it can be washed and sterilized at the same time while it passes through the solution.

By the way, as mentioned above, the sterilization method using ultraviolet rays has various advantages such as ease of equipment installation, low sterilization cost, and ability to sterilize in a dry state. Complete sterilization cannot be expected if dust etc. adhere to the product.

However, the method of the present invention utilizes the advantages of sterilization using ultraviolet rays, eliminates the disadvantages of sterilization using ultraviolet rays, removes dust from the sheet-like material by passing it through an ultraviolet-transparent solution, and also performs chemical sterilization. It also allows for complete sterilization.

The following description will be made based on the embodiments shown in the drawings.
First, the embodiment shown in FIG. 1 will be explained. A sheet-shaped packaging material 3 is advanced from A to B, and is passed through a sterilization treatment tank 1 in the process of progressing.

Tank 1 contains an ultraviolet-transparent solution, which contains boiling water, alcohol, hydrogen peroxide, β-propiolactone, mustard powder, advanced mustard powder, sodium hypochlorite, peracetic acid, polyethylene glycol, Formaldehyde, organic acids, etc. However, this solution is not effective unless the ultraviolet rays with a wavelength of 254 hm are sufficiently transmitted to the packaging material.

On the wall of the tank 1, a sheet-like material is sandwiched between the upper and lower walls of which are made of quartz glass, etc., and ultraviolet transmitting windows 7, 7 are provided to sufficiently transmit ultraviolet rays with a wavelength of 254 hm.
Correspondingly, ultraviolet sterilization lamps 2, 2, 2, 2 are installed as ultraviolet sterilizers.
The germicidal wavelength of this UV germicidal lamp is, for example, 254h.
The bactericidal power depends on the intensity and irradiation time of the lamp itself, so in order to increase its effectiveness, either increase the intensity of the lamp itself, increase the number of lamps and lengthen the irradiation time, or bring them closer together. , or by reducing the packaging material line speed.

Further, the solution in the sterilization treatment tank 1 is circulated by a pump 8.

In this circulation pipe 9 there is a sterile filter 4.

This filter 4 is provided to prevent dust and microorganisms removed in the tank 1 from remaining in the tank 1.

In this way, the sheet-like packaging material moves through the tank 1 from A to B via the guide roller 10, and is irradiated with ultraviolet light in the tank 1 to remove dust and microorganisms adhering to the surface.

The sheet-like packaging material 3 that has passed through the tank 1 is first blown off most of the liquid adhering to it by jet sterile air jetted from the nozzle 6 in the piping 11, and then from the sterile dry air jetting ports 5, 5. dried with air. 2 shows a sterilization treatment tank 1 connected to a chemical disinfectant cleaning tank 12, and the same parts as in FIG. 1 are designated by the same reference numerals.

This is when a chemical disinfectant is used in the tank 1, and is intended to ensure that no chemical disinfectant remains on the sheet-like packaging material.

Sterile water made of sterile ethanol or the like is used in the chemical disinfectant cleaning tank 12 and is circulated using a pump 13.

If a chemical sterilization and decomposition tank 14 is provided in the circulation pipe 15, the residue can be completely removed from the sheet-like material.

Note that a system may be used in which the sterile water does not flow in a circulating manner but flows in one direction.

Next, an example in which a test was conducted using the ultraviolet sterilizer shown in FIGS. 1 and 2 will be described.

Example 1 This example is an example in which a test was conducted using the ultraviolet sterilizer shown in FIG.

The sterilization treatment tank 1 uses boiling water, the ultraviolet sterilizer 2 uses a UV-C type germicidal lamp manufactured by Braun Boverikampani (BBC) in Switzerland, and the sheet packaging material 3 uses PET with a thickness of 12μ and PET with a thickness of 40μ. A laminated plastic packaging material made of PE and sterile dry air 5 at 90°C was used. Packaging material 3 was sprayed with 10 ⁶ bacteria/10 cm ² of B. subtilis bacteria, and after drying, a sterilization test was performed using the above-mentioned apparatus. The line speed is 30m/min, and the intensity of ultraviolet rays on the packaging material surface is 70W/cm ² .S.

The packaging material put in from A as described above was completely sterilized when it came out from B.

Example 2 This example is an example in which a test was conducted using the ultraviolet sterilizer shown in FIG.

A 5% conc hydrogen peroxide solution at a temperature of 22°C is used in the sterilization treatment tank 1, a UV-C type sterilization lamp manufactured by Braun Boverikampani (BBC) of Switzerland is used as the ultraviolet sterilizer 2, and a sheet packaging material is used. 12 for 3
A laminated plastic packaging material made of μ-thick PET and 40 μ-thick PE is used, sterile dry air 5 is 90°C, water is used in the chemical disinfectant cleaning tank, and carbon dioxide is used in the chemical disinfectant decomposer 14. A manganese-filled filter was used in each case.

Packaging material 3 was sprayed with 10 ⁶ /cm ² of B. subtilis bacteria, and after drying, a sterilization test was performed using the above-mentioned apparatus.

The line speed is 50m/min, and the intensity of ultraviolet rays on the packaging material surface is 70mw/cm ² .S.

The packaging material put in from A as described above was completely sterilized when it came out from B.

In any case, since the present invention is configured to irradiate ultraviolet rays while the sheet-like material passes through an ultraviolet-transparent solution, it is possible to clean and remove dust, bacteria, etc. adhering to the sheet surface. It has the characteristic that it can completely sterilize and sterilize at the same time.

[Brief explanation of the drawing]

1 and 2 are schematic diagrams of the ultraviolet sterilizer of the present invention according to different embodiments, respectively. 1... Sterilization treatment tank, 2... Ultraviolet germicidal lamp,
3... Packaging material, 4... Sterile filter, 5...
Sterile dry air outlet, 6...Jet sterile air nozzle, 7...Ultraviolet transmitting window, 8...Pump, 12...Chemical sterilizer cleaning tank, 13...Pump, 14...Chemical sterilizer decomposer.

Claims (1)

[Scope of Claims] 1. An ultraviolet sterilizer is installed in a sterilization tank in which a sheet-like object passes through an ultraviolet-transparent solution, and the sheet-like object is irradiated with ultraviolet rays; An ultraviolet sterilizer that simultaneously cleans and sterilizes dirt, bacteria, etc. adhering to the sheet surface while objects pass through it. 2. The ultraviolet sterilizer according to claim 1, wherein an ultraviolet ray transmitting window made of quartz glass or the like is provided on the wall of the sterilization treatment tank, and the sheet material can be irradiated with ultraviolet rays through this window. 3. The ultraviolet sterilizer according to claim 1, wherein the solution in the sterilization tank is circulated through a sterile filter. 4 A chemical disinfectant cleaning tank configured to circulate or unilaterally circulate sterile water such as sterile ethanol, etc. is connected to the sterilization tank, and the sheet-like material that has passed through the sterilization tank is connected to the tank. The ultraviolet sterilizer according to claim 1, wherein the ultraviolet sterilizer is configured to allow the ultraviolet rays to pass through. 5. A jet nozzle for blowing off sterile air to blow off the sterilizing cleaning liquid adhering to the sheet-like object and a sterile dry air jet for drying the sheet-like object are connected to the sheet-like object next to the sterilizing treatment tank or chemical disinfectant cleaning tank. The ultraviolet sterilizer according to claim 1, wherein the ultraviolet sterilizer is arranged sequentially in the direction of travel.