US 3247957 A
Description (OCR text may contain errors)
pril 26, 1966 M. s. KEMBLE STERILE PACKAGING AND THE LIKE Fil ed Aug. 17, 1964 b mm e K E. W8 n I e M United States Patent Ofiice 3,247,957 Patented Apr. 26, 1966 I 3,247,957 STERHLE PACKAGING AND THE HIKE Mern S. Kemble, Deeriield, Ohio, assiguor to Hospital Supply and Development Company, Braddock, 1921., a corporation of Pennsylvania Filed Aug. 17, 1964, Ser. No. 339,986v 4 Claims. (Cl. 206-632) This invention relates to sterile packaging, that is, a system in which the product is enveloped. in a sealed package of film, preferably plastic, thereby eliminating post sterilization, sealing and/or handling steps. More particularly, this invention pertains to the packaging of regular or irregularly shaped contents in a container comprising an impervious plastic film, e.g., polyethylene, which is presealed and contains an opening closed by a wafer cover of a material, e.g., paper, which will breathe so as to permit sterilization of said contents therethrough and through said opening. 4
Heretofore, it has been a common practice in the gas sterilizing of products packaged in plastic film to do such sterilizing with one side or end of the plastic package, or container, open, or with the edges of the open side or end stitched together with a cotton wick for air and gas ingress and egress. Such incompletely packaged products were then placed in a sterilizer chamber and put under vacuum withdrawing the air from the interior of the containers through the open side or end, or such cotton wicking. Following such expulsion, a sterilizing gas at appropriate temperature, such as a mixture of ethylene oxide and carbon dioxide, was admitted and the pressure raised to the level desired for the period 'of time required at the selected temperature for sterilization. Then, the sterilizing gas was removed from the chamber and package under vacuum and air readmitted until the interior of the chamber and the sterilized contents thereof were at atmospheric pressure. containers from the sterilizing chamber, care had to be exercised in performing the final edge closing seal on such containers if loss of sterility of the contents were to be avoided. In the case of the cotton-wicked operation, if the wicking were too far from the contents of the film container, such film could press against itself and might pinch off the flow of sterilizing gas to the inside. On the other hand, if the wicking were too close to the contents of the container, then it often became difficult to make the final edge seal, as by hot or cold sealing, between the wicking and the contents before cutting off the wicking strip outwardly of thenewly sealed edge. Further, while paper which breathes sufficiently for such air evacuation, gas sterilization and air readmittance has been used for the sterilized packaging of relatively flat objects, it has been considered impractical for use as a container for bulkier objects such as cartons and bottles which are to besold in viewable and/or sterilized condition. Such arises from the fact that in sterile products, even though paper container may be presealed before sterilization, it may not have any wrinkles therein and, further, normally cannot be used with bulkier objects to form an enveloping package in which the sealed edges are relatively close-to the contents of the container, as one can do with plastic film.
Deficiencies of prior practices are overcome by practices of this invention. In this invention, the enveloping package, substantially irrespective of the size and shape of the contents, can be completely sealed with the edges of the package relatively close to the contents, if desired, and suchpackaged products subjected to air and sterilizing gas alternately under vacuum and pressure conditions for effective sterilization, without rupture of the enveloping film container, or crushing of the contents thereof, and, without danger of loss of sterilization in the handling Upon removal of the open, or cotton wicked,
when they are taken out of the sterilization chamber. Instead, such sterilized sealed packages taken out of such chamber may be immediately placed in shipping cartons, or sent to the stock room without risking contamination of the contents of such containers.
Other objects, features and advantages of this invention will be apparent from the following description and the accompanying drawings, which are illustrative only, in which FIGURE 1 is a plan view of a sterile plastic film package containing a carton with goods therein, such package being constructed in accordance with one embodiment of this invention;
FIGURE 2 is a partial view, somewhat enlarged, taken along line IIII of FIGURE 1;
FIGURE 3 is a view of the foregoing embodiment of this invention prior to the affixation of a breathing wafer closure and with the plastic bag container ready for the reception of contents prior to final edge sealing and sterilization;
FIGURE 4 is an enlarged perspective view of a corner of the same embodiment prior to sterilization but after the contents have been inserted, the remaining edge sealed close to the contents and the wafer aflixed, one end of such wafer being shown turned up merely to better illustrate the mode of construction of such embodiment;
FIGURE 5 is a view of another embodiment of a packaging container of this invention; and
FIGURE 6 is a view of the container of FIGURE 5 in fully closed and sealed condition with a cylindrical bottled product therein as it would appear both before and after sterilization.
Referring to FIGURES 1 to 4, inclusive, of the drawings, a plastic container 10 comprising one embodiment of this invention is illustrated therein. Container 10 comprises a bag which is made of a film of plastic 11, such as polyethylene, which is impervious to air, gas and moisture. Such preferably is transparent, but may be translucent or opaque and provided in substantially any desired color. The plastic bag 11 is provided with a breathing opening 12 adapted to be closed by a breathable closure 13 affixed to the outside surface of the bag around the edges of opening 12 by a suitable adherent material.
Closure 13 in the illustrated embodiment is in the form 4 of a breathable paper wafer which will permit air and gas to pass therethrough sufficiently readily to pass in and out, as the case may be, of opening 12 when container 10 is completely presealed around all of the continuous marginal edge 14 after insertion thereinto of the desired contents 15 which may be in the form of a box containing wares, as shown, or other shape, or which may be loose contents. Sealed edges 14 may be thermally sealed as in the case of polyethylene film, or cold sealed together with some suitable material utilizing a suitable adherent material therebetween, such as a latex type or some pressure sensitive adhesive. As shown, film 11 is relatively transparent and has considerable strength. Hence, the box 15 can be viewed through container 10 and the corners thereof may pass sharply around the corners of the box 15 with the result that the sealed sides of edges 14 in container 10 are relatively close to the sides of the carton or box 15, thereby making for a neater and more sightly package with minimal use of the exterior packaging material in the form of film 11. The adherent material 16 may be applied, in the case of a latex-type adhesive, to the exterior of film 11 completely around opening 12 and to the marginal edge of the underside of wafer closure 13 so that upon contact between the layers of adherent material 16 on film 11 and on the underside of wafer 13, wafer 13 is firmly aflixed to film 12 becoming a part of container 10 and sealing 01f access to opening 12 except through the closure 13 itself. Closure 13 can breathe" and may be made of a breathable paper such as the brand known as Steriseal.
Printed label indicia 17 may be applied to the outside of wafer 13, if desired. While the latex-type adherent material 16 adheres upon contact as a cold seal, it is, of course, possible to use other adherent or packaging materials which may be sealed using heat for such sealing. Hence, in container 10, after product 15 is inserted therein and the remaining edge 14 is sealed, such edge seal extends continuously around the periphery of package 10 as shown in FIGURE 1 just as the closure seal extends continuously around the edge of the closure 13 and the opening 12. While all four sides of package 10 are completely presealed at 14 before sterilization in the illustrated embodiment of this invention, there may be fewer sides which need such sealing where there are no discontinuous edges present as when the upper and lower sides of a plastic bag are made by folding over a single sheet of plastic so that the side where the fold comes has no such discontinuous edges and thus requires no sealing. The opening 12 may be prepunched in the sheets or continuous Web of film 11 as received for use, or it may be placed therein either before or after the closure 13 is attached. Further, while opening 12 is shown as a single opening, it may be a plurality of openings as shown in the embodiment of FIGURES and 6, or there may be more than one opening in more than one place and/ or on more than one side of package in which event each would be covered by a closure 13 as described. Preferably, however, the number and size of the openings or gas-ports are kept as small as possible, consistent with proper sterilization by sterilizing gas techniques, to minimize entry of moisture and to reduce manufacturing costs. The porosity of the material of closure 13 will be such that it permits, when subjected to a suitable pressure differential, sufficiently free ingress and egress therethrough of gas, including air and vapor, in the course of sterilizing completely sealed package 10 with contents 15 therein. Thus, closure 13 acts as a barrier to bar the passage of any substance adverse to the sterile quality of the inside of package 10 and the contents thereof after sterilizing when there is no pressure differential to cause the closure 13 to breathe. And, the use of plastic film 11 and the relatively small size of closure 13 makes it extremely unlikely that any moisture can get into the interior of package 10 which is always shipped and/or handled so that it will not get wet.
The bag formed by film 11 in the embodiment in FIG- URES 1 to 4, is shown in FIGURE 3 as presealed continuously around three of the edges 14, with the fourth edge open to form a mouth 18 which is sealed to form the fourth remaining sealed edge 14 continuous with the others after the contents 15 are inserted into the bag through mouth 18. Further, the package 10 is completed by the affixation of closure 13, before or after such final edge sealing, and a complete package 10 is present ready for the market except in one respect, that is, it still requires sterilization. While closure 13 is shown as a single wafer member, it may be made in two parts, viz, a smaller breathable paper disc large enough to cover opening 12 and a still larger annular label coated for example with a pressure sensitive adhesive on the underside thereof with the opening in the annular label smaller than the diameter of the paper disc so that it can affix itself to the disc and in turn affix both itself and the disc to the film 11 so that the disc completely covers opening 12. The latter arrangement minimizes handling of the breathable disc or wafer and the possibility of damage thereto during the manufacturing operation. Moreover, the use of the overlying annular label, which obviously need not be a breathable material but rather can be the same material as the film 11, affords a more positive r'etainment for the disc or wafer.
Such sterilization may then be effected with the completely presealed package 10 under this invention and hence requires no post-sealing and/ or handling operations which may adversely affect such sterilization. Thus, in the case of completely presealed package 10 after insertion in an evacuation and sterilizing chamber, the air in container 10 can be evacuated under vacuum from the interior thereof and from the interior of box 15 through the opening 12 and closure 13, following which the sterilizing gas under pressure can flow in a reverse direction into the interior of the container 10 and box 15 for the prescribed time and at the prescribed temperature to effect the desired sterilization. Following such sterilizing step, the sterilizing gas can be removed under vacuum in the same way that the air was initially removed, following which the outside air can be admitted into the sterilizing chamber and will flow through closure 13 and opening 12 into the interior of the envelope comprising package 10 and into the interior of the box 15 without affecting the sterility of such box and the product therein, or the interior of the outside package. The complete package 10 and contents 15 then are ready to be placed into a shipping carton, or added to inventory, or otherwise handled without disturbance of the sterile quality which remains intact until the package is opened by the user.
A modified embodiment of this invention illustrated in FIGURES 5 and 6 illustrates the same inventive principal hereinabove disclosed, applied to a noncubical object in the form of a bottle 20, the inside contents of which have previously been sterilized, or the bottle 20 can be replaced by some other irregularly shaped object or inside container, or loose material may be the contents, as desired. Portions of the package embodiment of this invention shown in FIGURES 5 and 6 which correspond substantially in nature and function to parts illustrated in the above first-described embodiment are provided with the same reference numerals with the addition of a prime accent thereto. In the case of the embodiment shown in FIGURES 5 and 6, while the edge seams 14' have not been made relatively close to the contents 15', the use of film 11 to make container 10' is preferred in that instance because where the film 11' is transparent or translucent and the contents 15', as in the case of bottle 20, are readily viewable by a prospective purchaser, or by a prospective user who may wish to read a label on the bottle through the sterile packaging wall 11 before opening the package and handling the bottle itself. And, in the case of adherent material 16', it may be preapplied only in the modified embodiment to the outside of the film 11' around the group of openings 12', such adherent material 16' being in the nature of a pressure-sensitive adherent sealing material to affix closure 13'. Sterilization of package 10 would take place after the complete presealing of the package with the contents therein as shown in FIGURE 6, for achievement of benefits of this invention.
While reference has been made to plastic film because of its desirable strength and transparency properties, other impervious film materials may be used including papers such as those treated with resins to make them impervious. Moreover, embodiments of this invention may be made in which the impervious film material is provided with an integral porous breathable portion which does not have to be separately affixed for achievement of advantages of this invention. And, although the illustrated embodiments have been described in connection with gas sterilization of the interior thereof after complete presealing, it is understood that practices of this invention may be utilized in connection with the chemical treatment and/or the conditioning of contents and packages of this invention by the use of some gas or gases and a breathable closure portion without exposing such contents to outside contamination.
Various changes may be made in details and uses of the illustrated embodiments and other embodiments and uses devised without departure from the spirit of this invention or the scope of the appended claims.
1. A sterilizable package comprising an envelope of thin impervious packaging film relatively closely surrounding the contents thereof, said envelope having all discontinuous adjoining edges pre-sealed, said envelope having a gas-port opening therethrough, a gas-pervious Wafer closing said opening, and an annular Wafer retaining member having its inner periphery overlying the outer edges of said wafe and having its outer periphery extending outwardly thereof, said retaining member having its outer and inner peripheral portions sealingly affixed respectively to said envelope and to said wafe around said opening to complete the sealing of the inside of said package, the opening of said annular member being in substantial registration with the envelope opening.
2. The combination according to claim 1 characterized in that said pervious wafer is' a wafer of paper which is pervious to the passage of sterilizing gases when subjected to a differential pressure upon the two sides thereof, and said envelope and said retaining member openings are relatively small in size so as to admit suflicient sterilizational gas while minimizing admission of moisture.
3. A sterilizable package comprising an envelope of thin impervious packaging film relatively closely surrounding the contents thereof, said envelope having all discontinuous adjoining edges pre-sealed, said envelope having a gas-port opening therethrough, a gaspervious wafer closing said opening and sealed about the edges thereof to said envelope to complete the sealing of said envelope, and an annular Wafer retaining member having its inner periphery overlying the outer edges of said wafer and having its outer periphery extending outward-1y thereof, said retaining member having its outer and inner peripheral portions sealingly affixedrespectively to said envelope and to said wafer around said opening to ensure the sealing of the inside of said package, the opening of said annular member being in substantial registration with the envelope opening.
4. A packaging and sterilizing process comprising the steps in variable order of preparing a container of thin impervious packaging material, inserting contents into said container while at least one portion thereof is open to receive said contents, providing -a sterilizing gas pervious portion in said container including a breathable wafer secured thereto, said portion being of a size to admit sufiicient sterilizing gas while minimizing admission of moisture, registering the opening in an annular retainer for said wafer with said container pervious portion, sealing said retainer both to said wafer and to said container to ensure retention of said wafer on said container and the sealing of said container, evacuating the interior of said container, passing sterilizing gas through said pervious portion into said container, and reducing the ambient pressure of said container of withdraw said sterilizing gas through said pervious portion.
References Qited by the Examiner UNITED STATES PATENTS 8/1961 Stannard 229-3.1
FOREIGN PATENTS 8/1946 Great Britain.