FI94043C - Method for providing an odorless and sterile package and a sterilizable product package obtained by the method - Google Patents

Description

94043

The invention relates to a method for providing an odorless and sterile package, in which a nonwoven and / or plastic textile product is packaged in a substantially gas-impermeable package for sterilization by irradiation. The invention also relates to a sterilizable product package provided by the method.

Sterile packaging, such as packaging for hospital equipment, often uses pouch-like, airtight, or breathable, but bacteria-impermeable, packages in which the media to be packaged is placed prior to sealing the packages. Sterilization is accomplished by irradiating the package with ionizing radiation, such as gamma radiation, ultraviolet light, or other means. The products to be packaged can be surgical textiles, surgical instruments, various hoses, syringes, cannulas, etc.

The problem with these types of packages is the strong odor emanating from them when opened. The radiation causes the oxygen inside the package to be converted to ozone, which usually reacts with the molecular chain of the plastic-based product to form malodorous compounds such as acetic acid and butanal. In addition, the oxidizing environment impairs the mechanical strength of the plastic products in the package. This problem has been clarified and solved e.g. EP 218003. The package disclosed in this publication 30 uses an oxygen scavenger such as activated iron oxide to eliminate odor. However, the solution requires a two-layer package, a breathable inner and a tight outer layer, between which the oxygen and thus odor-corrosive substance is placed. The disadvantages of such a package 35 are its complexity and the 2 k 94045 iron oxide to be added to it separately.

A method is also known for sterilizing mainly small plastic articles, in which the formation of ozone is prevented by displacing the oxygen contained in the packages placed in a separate container with a shielding gas, cf. e.g., U.S. Patent 5,014,494. The purpose is to prevent deterioration of the mechanical strength and appearance of the products. However, the displacement method is not suitable for packaging containing textiles, as they always leave 10 enough oxygen in their folds and folds so that odor nuisances are not eliminated.

The object of the invention is to provide such a method for sterilizing a package and a method sterilized by a method by means of which the product can be easily and safely packaged for sterilization and in which the odor nuisance of known packages after irradiation is minimized. To achieve this, the method according to the invention is characterized by the following steps, directed at individual packages: - placing the folded textile product in the package; 20 - creating a vacuum in the package by removing air from it; - adding shielding gas to the package; - sealing the package by irradiation; for processing.

The advantages of the invention include not only the odorlessness of the package but also its simplicity and the speed with which the various steps can be performed. The air can be removed and the shielding gas added with the same nozzle. The package can be a simple plastic package, so it also becomes inexpensive.

Other preferred embodiments of the method according to the invention and the product package according to the invention are characterized by what is stated in the claims below. The invention will now be described in more detail with reference to the accompanying drawings, in which Figures 3 to 94043 show a package according to the invention at various stages of its manufacture, Figures 5 to 8 show gas chromatograms of the contents of packages and reference packages according to the invention.

A sterile package according to the invention containing a product to be sterilized (e.g. a surgical jacket) is obtained by placing the product 1 in a plastic package 2 (Fig. 1), after which the package is deaerated e.g. by a vacuum pump (not shown) through a hose 3 (Fig. 10 2) . A protective gas such as nitrogen or carbon dioxide is then added to the package 2 (Figure 3). The package is sealed and sterilized by gamma radiation (Figure 4), after which the package is ready for use.

Practical experiments have shown that the bad odor from the radiation-15 sterilized package when opening the package is almost completely eliminated when using the packaging method according to the invention.

Table 1 shows the results based on the • sensory evaluation of the odor (scale 0 ... 3). Sample A is a 20 gamma-sterilized package without a shielding gas, Sample B a corresponding package with a shielding gas nitrogen, and Sample C a corresponding package with a shielding gas carbon dioxide. As can be seen from the table, most evaluators perceive the odor of samples A to 7 to be strong (mean about 1.8), while the odor of samples B and C is typically just detectable (mean about 1). In samples B and C, the oxygen content of the packages was less than 1%, in sample A it was the normal oxygen content of the air (21%). Depending on, among other things, the size of the product to be sterilized, a suitable oxygen content in the package has been estimated at 0.5 to 5%.

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SAMPLES

EVALUATION ABC

1 0.75 1.25 0.5 2 2 0.5 1 5 3 2.25 0.25 1.75 4 2 1.5 1.5 5 1.75 1.25 0.5 6 2 1 0, 5 7 1.5 1.25 1 10 TOTAL 12.25 7 6.75 X ± SD 1.8 ± 0.5 1.0 ± 0.5 1.0 ± 0.5 TABLE 1

Absence or significant reduction of odor. Fifteen reasons have been studied at the University of Jyväskylä by gas chromatography and mass spectrometry measurements (Figures 5-8). Figure 5 shows a Gas Chromatogram of an unirradiated, air-containing package showing only relatively low concentrations of various compounds. Fig. 6 shows the effect of irradiation when the air-containing package (cf. Fig. 5) is irradiated with gamma radiation. The gas chromatogram shows not only a significant increase in the compounds already present in the package, but also mainly the strong formation of two previously missing compounds. These compounds are butanal and acetic acid, both of which are known to smell very strong! makkaiksi. The formation of butanal and acetic acid is likely to be caused by the reactions of ozone caused by gamma radiation with the plastic materials in the package.

Reactive ozone reacts with plastic polymers, causing oxidation reactions in which e.g. malodorous compounds-. this is born.

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Figures 7 and 8 show gas chromatograms of the respective packages when the packages according to the invention have first been evacuated and then filled with shielding gas, nitrogen (Figure 7) or carbon dioxide (Figure 58). It is observed that the butanal and acetic acid peaks have disappeared almost completely or even completely. Thus, the sensory absence or significant reduction in odor appears to be due to the fact that the shielded gas-filled packages show almost no evidence of the two highly odorous substances, butanal and acetic acid, present in the air-irradiated package (Figure 6). Protective gases other than those mentioned above can also be used for a similar purpose within the scope of the invention.

Due to the low oxygen content, little or no ozone formation during irradiation (cf. EP 218003) causes the pungent odor in known packages (sample A in Table 1) to be eliminated in the packages provided according to the invention (samples B and C in table 1). ).

It will be apparent to those skilled in the art that the various embodiments of the invention are not limited to the examples set forth above, but may vary within the scope of the claims below.

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Claims (7)

A method of providing an odorless, sterile package, wherein, according to the method, a textile product (1) of nonwoven fabric and / or plastic is packed in a gas-impermeable package (2) to be sterilized by training, characterized by that it comprises the following stages, which are applied to the individual packages: 10. a weighted textile product (1) is placed in the packaging (2)? - in the package, a vacuum is formed by removing the air from it; - in the package (2), protective gas is supplied; 15. the package is sealed to be sterilized by irradiation. 2. A method according to claim 1, characterized in that nitrogen is used as protective gas. A method according to claim 1, characterized in that carbon dioxide is used as a protective gas. 4. A method according to claim 1, 2 or 3, characterized in that air is removed from the package such that the amount of residual acid has been minimized to make up at most 1% of the amount of gas in the package, after the supply of the protective gas. An odorless and gas-impermeable package (2) for a textile product of nonwoven fabric and / or plastic to be sterilized by irradiation, characterized in that the package is formed by the package containing the weight of the textile product (1), r and in which after the removal of the air, protective gas has been added for sterilization by irradiation. A product package according to claim 4, characterized in that the package contains nitrogen as protective gas. • 94043 7. A product package according to claim 4, characterized in that the package contains carbon dioxide as protective gas. ♦