US3507386A

US3507386A - Package for sterilized articles

Info

Publication number: US3507386A
Application number: US758922A
Authority: US
Inventors: Ichiro Ishii; Yasuo Kajihara
Original assignee: Jintan Terumo Co Ltd
Current assignee: Jintan Terumo Co Ltd
Priority date: 1968-09-10
Filing date: 1968-09-10
Publication date: 1970-04-21
Anticipated expiration: 1987-04-21

Description

A ril 21, 1970 ICHiRO lSHll ETAL v 3 507 335 PACKAGE FOR STERILIZED ARTICLES Filed Sept. 10, 1968 United States Patent 3,507,386 PACKAGE FOR STERILIZED ARTICLES Ichiro Ishii and Yasuo Kajihara, Tokyo, Japan, assignors to Jintan Terumo (30., Ltd., Tokyo, Japan, a corporation of Japan Filed Sept. 10, 1968, Ser. No. 758,922 Int. Cl. A61b 19/02 US. Cl. 206--63.2 6 Claims ABSTRACT OF THE DISCLOSURE A package for sterilized articles comprising receptacle made of gas-impermeable film for enclosing the articles, and gas-permeable germproof paper constituting a small passage inside the receptacle, through which sterile gas can be penetrated to sterilize articles contained Within the package.

The present invention relates to a package for sterilized articles which is not only suited for use in gas sterilization of medical implements and materials such as a syringe, gauze, etc. which must be clean and free from any kind of germs before use, but also capable of preserving such articles in their fully sterilized condition over a long period of time after sterilizing treatment.

Heretofore, this type of package has consisted of transparent plastics film for easy observation of the contents. However, since plastics have poor heat resistance, they present difficulties in thermal sterilization. Accordingly, it has been required to disinfect medical articles in advance and seal them up under a well sterilized condition. However, such sterilizing and packaging processes involve considerable complications and are also undesirable from the standpoint of operating efficiency.

Therefore as a means to eliminate the aforementioned drawbacks, one of the known methods proposed to date consists in preparing a package from a gas-impermeable film made, for example, of plastics, perforating a plurality of through apertures of a desired size at several appropriate points on the side of the package, bonding thereon, for example, a sheet of paper which has gaspermeability and yet does not permit the penetration of bacteria, so as to close up the aforesaid apertures, and disinfecting packaged articles by placing the package in an atmosphere of sterilizing gas such as ethylene oxide.

While such package may indeed be useful in disinfect ing enclosed articles with a sterilizing gas, the gas-permeable germproof paper available to this end has poor water repellency and is very vulnerable to water and moisture. Accordingly, it can not avoid encountering a great many inconveniences or difficulties. For example, where such kind of paper absorbed water or moisture, it naturally tended to be peeled off from its place, damaged or broken. As a result, elaborately disinfected articles were most likely contaminated and, unless sterilized again, could not be used safely soon after being taken out of the package, particularly under unfavorable conditions prevailing in areas such as those affected by natural calamities or other causes.

To make up for such shortcomings, it might be contemplated to reduce the aforementioned apertures to an extremely small size or to cover the part of the package, on which is superposed the germproof paper, with gasimpermeable film. However, this would have an undesirable effect, for example, of obstructing the introduction of sterilizing gases, consuming a great deal of time in completing sterilization, or presenting considerable difficulties in properly closing up the rugged side of the package after sterilization of enclosed articles.

3,507,386 Patented Apr. 21, 1970 The present invention has been accomplished with the view of providing a package for sterilized articles wherein efiicient sterilization can be carried out using sterilizing gases and, if required, the paper tape enclosed therein through which is sterilizing gas is allowed to permeate can be very easily rendered fully waterproof, thereby to preserve the packaged articles of their well sterilized condition over a long period of time. The invention is characterized in that along the inner wall of one lengthwise end portion of a package made of heat-scalable film is formed a tubular tape of gas-permeable germproof paper extending from one crosswise end to the other crosswise end of the package and open to the outside thereof at one end or both ends, sterilizing gas introduced into the tubular paper tape is allowed to penetrate the paper Walls into the package, and if required, both open ends of the tubular tape are sealed water-tight after sterilization.

In the drawing:

FIG. 1 is a plan view of a package according to an embodiment of the present invention where a syringe is enclosed;

FIG. 2 is a sectional view on line II-II of FIG. 1;

FIG. 3 is a sectional view on line III-III of FIG. 1; and

FIGS. 4 and 5 jointly represent a plan view, with a part broken away, of a package according to another embodiment of the invention, showing the process of packaging an article for sterilization.

There will now be described the present invention with reference to the illustrated embodiments.

Numeral 11 in the drawing represents a package consisting of transparent gas-impermeable heat-sealable film. The package is prepared by folding in two a piece of such film cut in a rectangular form and heat sealing the superposed

open edges

13, 14 and 15, and is intended to enclose an article to be sterilized, for example, a syringe as shown in FIG. 1. In the lengthwise direction of the package along the inside of the sealed edge 14 is formed a tape 16 of gas-permeable germproof paper folded in two which extends from one cross-wise end 13 to the other crosswise end 15. The germproof paper tape is arranged in such a manner that its folded side faces the interior of the package. Further, tape, except for the folded part and its vicinity, is heat sealed to the inner walls of the package. The term gas-permeable germproof paper, as used in the present invention, means that type of paper which is gas-permeable at a higher gas pressure than the atmospheric but little gas-permeable at an atmospheric pressure, so that it has a property of preventing the penetration of bacteria under normal conditions. The concrete examples of such paper include kraft paper and the like.

Especially those consisting of long filaments, and having good permeability and smooth surface are preferable. Concerning the thickness of the gas-permeable paper, it should neither be too thin to hinder the passage of germ therethrough, nor too thick to create a gap likely to be formed between the gas-impermeable film and the crease of the paper heat-sealed to the film. Generally a thickness in the range of 30 to microns to be appropriate.

The paper can be easily heat-sealed to heat-scalable film such as plastics film but not to each other. Consequently, when the superposed crosswise ends 13 and 15 of the package 11 are heat-sealed, the opposite films of the folded paper tape 16 are not mutually heat-sealed, but remain separated as shown in FIG. 2 thereby to form a tubular hollow space or aperture 17 extending from one crosswise end 13 to the other crosswise end 15. Thus the inside and outside of the package 11 communicate with each other through said aperture 17.

When the package 11 constructed in the aforementioned manner is placed in a vessel filled with sterilizing gas, the gas is introduced from both open ends of the tubular aperture 17. Then as shown in FIG. 3, the gas penetrates the wall of that part 16a of the paper tape 16 which is not sealed to the inner walls of the package, namely, the folded section thereof, and is carried into the package thereby to sterilize a syringe 12 placed therein. In this case, the non-sealed part 16a of the paper tape 16 through which the sterilizing gas permeated has a broad area, and permits very effective sterilization. The interior of the sterilizing gas vessel is kept at a higher pressure than the atmospheric with sterilizing gas introduced under pressure, so that the gas can easily penetrate the gaspermeable walls of the paper tape 16.

In the package of the present invention, the gas-permeable paper is surrounded by gas-impermeable plastic sheeting, so that there is little danger of the paper relatively weak to water and moisture being damaged or broken due to an external cause, so that, once sterilized, a packed article can be preserved of its sterilized condition over a long period of time. Consequently the paper can well serve ordinary uses as it is. However, for better protection of the paper from water and moisture, it is advisable to attach, as shown in FIG. 4, a small heatsealable tab 18 made of the same material as the package 11 to the vicinity of the open ends of the tubular aperture of the paper tape 16, and after sterilizing of a packaged article, fold it in the direction of the arrow a and heat seal said opening. Then the opening can be fully sealed up as shown in FIG. 5, completely preventing the intrusion of water and moisture or bacteria through a medium of water into the interior of the package. Such arrangement could keep packaged articles fully sterilized even under extremely unfavorable conditions most likely exposed to heavy rainfalls or storms in particular, for example, in such environments as prevailing in affected areas.

The width of the non-sealed part 16a on the folded side of the paper tape 16 may be suitably selected taking into account the gas permeability of paper material and the conditions for sterilization. For example, when the width of the non-sealed part 16a is too narrow, the passage of sterile gas becomes difficult, and when it is too wide, the possibility of a packed article being contaminated by germs will considerably increase and the article may not be assured of its sterile condition.

One of the preferred example is as follows: Gas-permeable paper 16, having a width of 16 mm. is folded in two and fixed as shown in FIG. 1 to the inside of package 11, 50 mm. x 195 mm. in size, leaving non-sealed zone of about 8 mm. This package 11 is evacuated to remove the air filled therein taking about 20 minutes, and is sterilized in the atmosphere comprising 20 volume percent of ethylene oxide and 80 volume percent of carbon dioxide and having the humidity of 60-80%, at the temperature of 50-60" C., and at the pressure of 2.3-2.5 kg./cm. (absolute pressure) taking hours. Thus treated package proves to be maintainable of its sterilized condition over a long period of time. The air permeability of the paper employed in the above example is such that it takes 23 seconds to pass 100 ml. of air through the area of 645.16 mm. of the paper under the pressure of 87.9 g./cm.

A sterilized article can be easily taken out simply by tearing open the package at a suitable part. However, to ease the tearing, the package may be provided in advance with a notch 19 at an appropriate part as shown in FIG. 1. The aforesaid embodiments relate to the case where the paper used for the permeation of sterilizing gas was folded in two and fitted to the inside of the package. However, the present invention is not limited thereto, but allows the use of gas-permeable germproof paper which has been fabricated in advance into a tubular form having at least one of its ends open to the outside of the package as in the preceding case.

As mentioned above, the sterilization package of the present invention contains a tape of gas-permeable germproof paper shaped into a tubular form which allows sterilizing gas to permeate through the walls thereof. Since the package has a broad area through which the sterilizing gas can permeate, sterilizing efficiency is prominently increased. Further, the outer surface of the paper tape is protected with waterproof material to prevent the paper tape from being damaged or broken due to absorption of water or moisture, thus eliminating the danger of the packaged article being contaminated with. bacteria. Moreover, the tubular paper tape has an extremely small aperture open at the edge of the package through which the sterilizing gas is introduced, and is open to the outside of the package only at one end or both ends thereof. Therefore the sealing of the open ends of the paper tape can be easily carried out without being obstructed by an enclosed article. The package of the present invention also has the advantage that it can not only take the place of a separate bag commonly used in sterilizing an article, but also, after sterilization, be used as an ordinary sterilization package as it is or by sealing both ends of the paper tape. Further, if the gas-permeable paper tape is colored in various shades to indicate the kinds of package articles, there will be obtained convenience in handling.

The foregoing embodiments were associated with a package prepared by folding a gas-impermeable film in two. But the present invention is not limited thereto, but permits the use of a rectangular bag sealed in advance on three sides. In this case, a tape of gas-permeable paper may be bonded along the remaining open side by heatsealing as described above or other similar means so as to form a tubular aperture. The open side is tightly sealed after the enclosed article is completely sterilized.

The sterilizing package of the present invention is most suited in disinfecting and preserving medical implements such as a syringe, blood transfusion set, petri disk, rubber gloves, etc. or auxiliary medical consumables such as gauze, absorbent cotton, bandage, suturing threads, etc.

What is claimed is:

1. A package for sterilized articles comprising a receptacle formed of gas-impermeable film for enclosing an article to be sterilized, said receptacle having a first longitudinal edge therein which is hermetically heat-sealed, a tubular member formed of gas-permeable, bacteria-impermeable paper having at least one end thereof extending through said first edge, the interior of said tubular member being open through said end to the outside of said receptacle, the outer surface of said end being hermetically sealed to said rfirst edge, the interior of said tubular member being sealed off from direct communication with interior of said receptacle.

2. A package as claimed in claim 1 wherein said receptacle has a second longitudinal edge intersecting said first edge and a third longitudinal edge intersecting said second edge, said tubular member being positioned adjacent said second edge and extending through said third edge with the outer surface of the end of the tubular member extending through said third edge being hermetically sealed to said third edge.

3. A package as claimed in claim 1 wherein the package includes a sealable tab that if foldable over said one end of the tubular member for hermetical sealing of said one end.

4. A package as claimed in claim 3 containing a sterilized article, said one end of said tubular member being hermetically sealed by said tab.

5. A package as claimed in claim 1 wherein said tubular member is formed of kraft paper having a thickness between about 30 to microns.

6. A package as claimed in claim 1 wherein said tubular member is formed of paper tape folded back upon 5 6 itself and the overlapping edges of the tape are sealed 2,883,262 4/1959 Borin 206-43 within a longitudinal edge in said receptacle. 2,947,415 8/1960 Garth 20663.2 3,092,249 6/ 1963 Chapman 20646 References Cited 3,084,793 4/1963 Pitrnan 20663.2 3,229,813 1/1966 Crowe et a1 229-53 UNITED STATES PATENTS 5 3,073,507 1/1963 Trewella et a1. 229-62 1,798,406 3/1931 Dunn 229-15 2,433,056 12/1947 Masci 206-632 WILLIAM T, DIXSON, JR. Primary Examiner