JP2002059910A - Method and apparatus for sterilizing packaging film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constantly reliably perform complete sterilization which does not influence an object to be packaged in a single process by a simple and compact apparatus. SOLUTION: The method for sterilizing packaging film lies in such manner that one side of the packaging film is heated while another side is kept cool, preferably heated at 40 deg.C or lower. Adherent bacteria will be completely sterilized by heating one side of the film with flame, infrared radiation, far infrared radiation and the like. In case of sterilizing the film in such manner, it is desirable to continuously run the packaging film through the heating and the cooling corner for high effect in sterilization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for sterilizing bacteria adhering to a packaging film. For example, the present invention relates to a method for easily and reliably sterilizing a packaging film that is repeatedly run in a filling and packaging machine. The present invention relates to a method and an apparatus capable of performing processing.

[0002]

2. Description of the Related Art In so-called flexible packaging using a packaging film, in order to prevent a substance to be packaged from being stained by bacteria adhering to the packaging film, the packaging film is used in a filling and packaging machine. Inside or outside,
There have been various proposals for passing a sterilizing solution through a sterilizing solution or spraying a sterilizing solution on a packaging film.

[0003]

However, in such a conventional technique, a liquid tank of a sterilizing liquid such as hydrogen peroxide for dipping the packaging film or a means for spraying the sterilizing liquid is required. Liquid drying means, sterilization liquid circulation heating means, etc. are required, and the number of sterilization steps increases,
There has been a problem that the sterilizer has to be enlarged. Moreover, according to this conventional technique, there is a possibility that the sterilizing component adhered to the packaging film may have other effects on the packaged object, and on the other hand, deterioration of the sterilizing performance due to the continuous use of the sterilizing solution can be avoided. There was another problem.

[0004] The present invention has been made in view of such problems of the prior art, and is capable of performing complete sterilization in only one step and having no effect on the packaged object. The present invention provides a method for sterilizing a packaging film, which does not have a decrease in sterilization performance, and a simple and small sterilizer suitable for use in the method.

[0005]

A method of sterilizing a packaging film according to the present invention comprises heating one surface of a packaging film and cooling the other surface. Heat to above ℃ C, the other surface 40
It should be kept below ℃. In this method, for example, by heating one surface of the film with a flame, infrared rays, far-infrared rays, etc., it is possible to sufficiently sterilize bacteria attached to the film surface, which means that the surface is heated to 150 ° C. or more. This is particularly noticeable when heating is performed. In this case, in particular, accidental melting of the packaging film during heating can be sufficiently prevented by cooling the other surface of the film. The cooling temperature at this time is preferably as low as possible, for example, 40 ° C. or lower, more preferably 30 ° C. or lower, in order to enhance the cooling effect. When sterilization is performed in this way, it is preferable to continuously run the packaging film and pass it through the heating and cooling locations in order to enhance sterilization efficiency.

[0006] Further, the packaging film sterilizing apparatus of the present invention is provided with at least one roll around which the packaging film is wound, and is provided with a heater over a required angle range in close proximity to the peripheral surface of the roll. It is provided. In this apparatus, by heating one surface of the packaging film wound around the roll with a heater, it is possible to smoothly and surely sterilize bacteria adhered to the surface. In this case, the packaging film Can be appropriately selected in accordance with the angle range of the heater along the roll peripheral surface. Here, when two rolls are arranged in parallel with each other, the front and back surfaces of the packaging film are sterilized by supplying the heat of the heater to the packaging film wound around each of them in opposite directions. Can be processed.

As the heater, a flame radiation heater, a heating wire heater, a far infrared heater, or the like can be used.
Preferably, a flame radiant heater that can obtain a higher temperature and is well suited for high-speed processing is preferable.

[0008] In the case where the above-mentioned roll is used as a cooling roll to forcibly remove heat, the packaging film can be cooled as expected.

[0009]

FIG. 1 is a schematic sectional view showing an embodiment of an apparatus according to the present invention. In the drawings, reference numerals 1 and 2 denote two rolls arranged in parallel and close to each other. As shown, these rolls 1 and 2 are preferably cooled by water or other refrigerant to maintain their surface temperature at a constant
For example, it is maintained at 10 ° C. Reference numeral 3 denotes a packaging film sequentially wound around each of the rolls 1 and 2, and the packaging film 3 is applied to the rolls 1 and 2 under the action of the respective guide rolls 4 and 5. For example, the vehicle runs continuously with the inner surface and the outer surface being alternately contacted.

Then, heaters, for example, infrared heaters 6 and 7 are arranged close to the peripheral surfaces of the respective rolls 1 and 2 and are arranged along the respective peripheral surfaces over a required angle range. Here, the distance between the heaters 6 and 7 and the peripheral surface of the roll, and the arrangement angle range of the heaters 6 and 7 with respect to the center of the roll depend on the outputs of the heaters 6 and 7 and the amount of heat supplied to the film 3. It can be selected appropriately.
For example, when the distance of the heaters 6 and 7 from the roll peripheral surface can be changed, the distance can be adjusted according to the type of the packaging film 3 and the like.
During the winding work on the rolls 1 and 2, the heaters 6 and 7 can be moved away to a position where they do not hinder the work.

[0011] In the apparatus having the above-described structure, the packaging film 3 wrapped around the rolls 1 and 2 with the infrared heaters 6 and 7 turned upside down, for example, a sealant layer and a base film layer. When the laminated film is continuously run, the bacteria adhering to one of the layers is
Bacteria adhering to the other layer are sufficiently sterilized by the radiant heat from the heater 7, and the unexpected melting of the packaging film 3 at this time is sufficiently prevented by the cooling action of the rolls 1 and 2. Will be done. Here, the heating time of each layer can also be controlled by adjusting the running speed of the film 3.

As shown in FIG. 2, when the sealant layer of the packaging film used in the present invention is made of polyethylene having a thickness of 50 μm and the base film layer is made of a biaxially stretched nylon film having a thickness of 15 μm, 30 ° C. by heating to 30 ° C.
Assuming that the film is heated to 0 ° C. and the surface of the base film layer is cooled to 10 ° C. by a roll, if the thermal conductivity in the packaging film is constant, the temperature distribution in the film is as shown in FIG. Becomes Here, even if the surface of the sealant layer exceeds its melting temperature, the heating time is very short, so there is no danger of melt flow down of the sealant layer, etc. It is more effective when the layer surface is cooled. The same applies to the case of heat sterilization of the surface of the base film layer. Therefore, by using the guide roll 5 shown in FIG. Can be dispelled.

[0013]

As is apparent from the above description,
According to the method of the present invention, the bacteria adhering to the packaging film can be easily and always sterilized by heat simply by passing the film through one roll. There is no risk that the package will be affected. Further, in the apparatus according to the present invention, the above-described heat sterilization can be performed by a small apparatus having a simple structure.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of an apparatus according to the present invention.

FIG. 2 is a diagram illustrating a temperature distribution in a packaging film.

[Explanation of symbols]

 1, 2 rolls 3 Packaging film 4, 5 guide rolls 6, 7 infrared heater

Claims (7)

[Claims] 1. A method for sterilizing a packaging film, comprising heating one surface of the packaging film and cooling the other surface. 2. While continuously running the packaging film,
The method for sterilizing a packaging film according to claim 1, wherein the film is passed through heating and cooling points. 3. One side of the packaging film is heated to 200 ° C.
The method for sterilizing a packaging film according to claim 1 or 2, wherein the heating is performed as described above, and the other surface is maintained at 40 ° C or lower. 4. An apparatus for sterilizing a packaging film, comprising: at least one roll around which the packaging film is wound, and a heater located close to the peripheral surface of the roll. 5. The packaging film sterilizer according to claim 4, wherein two rolls are arranged in parallel with each other. 6. The packaging film sterilizer according to claim 4, wherein the heater is an infrared heater. 7. The packaging film sterilizer according to claim 4, wherein the roll is a cooling roll.