U.S. patent number 3,604,616 [Application Number 04/863,164] was granted by the patent office on 1971-09-14 for peelable envelope for sterile articles.
This patent grant is currently assigned to Edward Weck & Company, Inc.. Invention is credited to Edward E. Greif.
United States Patent |
3,604,616 |
Greif |
September 14, 1971 |
PEELABLE ENVELOPE FOR STERILE ARTICLES
Abstract
A sterilizable envelope for retaining articles before, during
and after sterilization and for maintaining sterility of the
contents for extended periods of time. One wall of the envelope is
made of an opaque material, such as paper, and the other wall is a
transparent material, such as a plastic film, these materials being
sealed together around the periphery of the envelope. A portion of
the periphery of the envelope is left open for receiving the
article to be stored, whereupon the seal may be completed for
subsequent sterilization and storage. Another portion of the
periphery of the envelope is configured for easy opening by
separating a portion of the two walls to expose the enclosed
sterile article.
Inventors: |
Greif; Edward E. (Philadelphia,
PA) |
Assignee: |
Edward Weck & Company, Inc.
(Long Island City, NY)
|
Family
ID: |
25340428 |
Appl.
No.: |
04/863,164 |
Filed: |
October 2, 1969 |
Current U.S.
Class: |
206/439; 206/440;
383/35; 383/908; 206/363; 206/484; 383/200 |
Current CPC
Class: |
B65D
75/30 (20130101); A61B 50/30 (20160201); A61B
2050/0065 (20160201); Y10S 383/908 (20130101) |
Current International
Class: |
A61B
19/02 (20060101); A61B 19/00 (20060101); B65D
75/28 (20060101); B65D 75/30 (20060101); B65d
033/02 (); A61b 019/02 () |
Field of
Search: |
;229/55,48T,3.5,62,66
;206/63.2,56A |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bockenek; David M.
Claims
What is claimed is:
1. An envelope for enclosing and retaining articles before, during
and after sterilization, comprising:
a unitary first wall of first flexible sheet material comprising a
first layer of said first material and a second layer of said first
material, said layers being mechanically bonded together; and
a second wall of second flexible sheet material being dimensionally
similar to said first wall;
said second wall being sealed to said first wall around three sides
of the periphery thereof to form said envelope having one end open,
said seal being in the form of a relatively narrow band.
2. The envelope of claim 1 wherein:
said second layer of said first flexible sheet material is thin
compared with said first layer and said second wall is arranged in
facing relation with and sealed to said second layer.
3. The envelope of claim 2, wherein:
said seal at the other end of said envelope is displaced inwardly
from at least one corner thereof to permit the confronting corners
of said walls to be freely separated.
4. The envelope of claim 1, wherein:
said sealed areas of said envelope being capable of withstanding
sterilization temperatures without deterioration of the seal
quality.
5. The envelope of claim 2, wherein:
said first and second layers comprising said first wall are paper
and said second wall is a thermoplastic film capable of being heat
sealed to said first wall.
6. The envelope of claim 4, wherein,
said second wall is nylon film.
7. The envelope of claim 3, wherein:
the open end of said envelope may be heat sealed to close the
interior of said envelope.
8. The envelope of claim 7, wherein:
said envelope may be opened by forcibly pulling said second wall
from said first wall, wherein said second layer in the vicinity of
said seal separates from said first layer and is ruptured from the
remainder of said second layer.
9. The envelope of claim 2, wherein:
said first flexible sheet material has a grain structure and is
arranged so that the grain of said first layer is oriented in a
transverse direction with respect to said envelope and the grain of
said second layer is oriented in a longitudinal direction with
respect to said envelope.
10. The envelope of claim 1, wherein:
said first and second walls are permeable to sterilizing gases and
steam while being impervious to dust and bacteria, said second wall
further being transparent.
11. An envelope for enclosing and retaining articles before, during
and after sterilization, comprising:
a flexible, unitary first wall comprising a first layer of
relatively thick paper and a second layer of similar relatively
thin paper, said layers being mechanically bonded together; and
a flexible second wall of transparent thermoplastic film
dimensionally similar to said first wall, said second wall being
heat sealed to said second layer of said first wall in confronting
relationship therewith, said seal being in the form of a relatively
narrow band around three sided of the periphery of said envelope
leaving one end thereof open;
said seal at the other end of said envelope being displaced
inwardly from at least one corner to permit the confronting corners
of said walls to be readily separated preparatory to opening said
envelope;
said first and second walls are permeable to steam and sterilizing
gases while being impervious to dust and bacteria.
Description
FIELD OF THE INVENTION
This invention relates in general to packaging techniques and, more
particularly, concerns a peel-open sterilizable envelope for
retaining articles before, during, and after sterilization and for
maintaining sterility of the enclosed articles for a substantial
length of time.
DISCUSSION OF THE PRIOR ART
It is common practice to package and store surgical instruments,
surgeons' gloves, dressings, sutures and like articles in sealed
envelopes in order to retain these articles in sterile condition
until they are used. In the commercial application of this
practice, a sterilized article or an article to be sterilized is
often furnished by the manufacturer thereof in a sealed envelope
capable of withstanding autoclave or gas sterilization. When the
article is to be used, the envelope is opened by some appropriate
method which is intended to expose the enclosed article for use
without causing it to become contaminated by contact with the
external portions of the package. Various envelope materials have
been used and, while paper is frequently employed because of its
ease of fabrication, its economy and its ability to permit
sterilization of enclosed articles, such packages have at times
been made of plastic, metal foil, metal foil laminates or some
combination of these materials.
Many prior packaging techniques give rise to certain problems. If
no portion of the package is transparent, care must be exercised to
ensure that each package is properly labeled as to its contents. On
the other hand, some wholly transparent plastic packages have no
provision for affixing the date of sterilization of the contents,
which is important in maintaining strict quality control over
stored sterilized articles. Another characteristic of many plastics
is that, after sealing, such a package is often difficult to open
without contaminating the contents. Another significant problem
common to many of the prior packages which are opened by separating
two layers which are sealed together is that the layers often tear
instead of at their bonding point with the result the package may
be only partially opened or not opened at all while a small portion
of one wall of the package is torn away.
SUMMARY OF THE INVENTION
Broadly speaking the present invention provides an envelope having
one wall preferably made of a dual-layered paper and the other wall
made of a transparent plastic film, such as nylon. Both the paper
and the plastic walls allow the contents of the envelope to be
sterilized after the envelope has been filled and sealed.
Provisions are made for easily opening the envelope by separating
the plastic from the paper so that the envelope always opens in
such a way as to expose the article contained therein for easy
accessibility to the user.
A particularly important feature of the envelope of this invention
is that the user, such as a doctor, nurse, or packager of medical
and surgical supplies, may place any desired article into the
envelope and seal it, after which the thus-completed package and
its contents may be sterilized by conventional means.
With one side of the envelope being transparent, the identity of
the contents is easily ascertained by visual inspection. The other
side of the envelope, being made of paper, provides a surface for
imprinting such words and symbols as desired by the manufacturer or
user and for recording information such as the date of
sterilization.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan view of a preferred embodiment of an envelope
constructed according to the principles of this invention;
FIG. 2 is a perspective view of the envelope of FIG. 1 being filled
through its open end;
FIG. 3 is a perspective view of the envelope of FIG. 2 after the
normally open end has been sealed;
FIG. 4 shows the envelope of FIG. 3 being opened to provide access
to the article enclosed therein;
FIG. 5 is an enlarged, broken away perspective view of a portion of
one side of the envelope of FIG. 1; and
FIG. 6 is a partial view of a second preferred embodiment of the
envelope of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference now to the drawing, and particularly to FIGS. 1
through 5 thereof, there is shown an envelope, designated generally
by reference numeral 11, having a rear wall 12 and a front wall 13.
The front wall is sealed to the rear wall at localized areas of the
envelope to form the elongated U-shaped seal 14 as indicated in the
drawing by dotted lines around the periphery of the envelope
adjacent the edges thereof. In order to facilitate opening the
envelope after it has been filled and sealed, the seal at top end
15 of the envelope is chevron shaped to provide corners of the
walls which are easily separated. The envelope of this invention is
formed with bottom end 16 open in order to allow articles to be
inserted before the envelope is completely sealed.
There are several characteristics which walls 12 and 13 should have
in order that envelope 11 have all of the desired features. For
example, they should be flexible yet have sufficient strength to
allow envelopes containing odd-shaped articles to be safely handled
and stored while being capable of withstanding the conditions of
sterilization. Furthermore, the walls of the envelope should be
permeable to steam and sterilizing gas while at the same time being
substantially impervious to dust and bacteria. It is desired that
one wall or a portion thereof be adapted to be imprinted with
appropriate legends and be capable of being written upon for such
purposes as recording the date of sterilization. The other wall, on
the other hand, should be transparent so that the contents of the
envelope may be readily identified upon visual inspection.
The walls of the envelope may be sealed together in any desired
manner which provides a positive, semipermanent, bacteria and
dust-free seal which is capable of withstanding sterilization
temperatures without deterioration of the quality of the seal. An
adhesive may be used or the walls may be mutually heat sealable.
Whatever the manner of sealing, this invention is directed to the
situation where the seal is so positive that the walls may be
separated only by stripping of a small portion of one of the walls
at the seal line. This would normally mean that the sealing
material had penetrated a fraction of the depth of one wall and
does not itself readily separate from either of the walls at the
sealed zones. The specific example described is concerned with a
wall of one material being heat sealable to the other wall which is
a different material but it should be understood that the
principles of the invention apply equally well to envelopes sealed
by adhesive means and which use similar materials adhered
together.
Certain thermoplastic films, such as nylon, have been found to
satisfy all of the above desired characteristics for wall 13.
Polyethylene is also suitable, but its use is generally limited to
gas sterilization. Material such as sterilizable Claremont kraft
paper is among those which have been found to have the necessary
properties for rear wall 12. A relatively strong bond is formed
when heat is applied to the nylon to cause it to soften and flow
into the pores of the paper. When the heat is removed, the envelope
may be opened only by separating the two walls, whereupon that
portion of thickness of the paper which is impregnated with nylon
will be stripped away from the remainder of rear wall 12.
It has been found that due to inherent variations in the thickness
of kraft paper and normal variations in the depth of penetration of
nylon into the paper, a single sheet of paper has not been fully
satisfactory for rear wall 12. Where the paper is thin or the nylon
penetration deeper than normal, or both, the paper may tear through
when an attempt is made to open the envelope, This results in a
partially opened package or one that fails completely to open in
the normal manner.
This invention, the essence of which is shown in FIG. 5, provides
an envelope having all of the desired properties and which may be
opened easily and positively. Rear wall 12 is comprised of two
layers of paper; a relatively thick layer 17, and a relatively thin
layer 18. Layers 17 and 18 are formed together and mechanically
bonded at the paper mill when the paper is made without the aid of
any adhesive substance. By passing damp paper in its formative
stage in two layers between rollers at the proper pressure and
temperature, the layers are mechanically bonded to effectively form
a unitary sheet which remains in that form until a force is
properly applied to separate the layers. This invention is not
concerned with the method of manufacturing the paper, and more
detailed description of this known process is not necessary
here.
When nylon sheet 13 is heat sealed to paper rear wall 12, a small
portion of the plastic enters the pores of the paper as shown at 19
in FIG. 5, and may, indeed, penetrate the entire depth of layer 18.
However, when the envelope is opened by separating the layers
commencing at chevron 21, as shown in FIG. 4, the portion of nylon
impregnated paper layer 18 which is part of the sealed area 14 is
readily separated from paper layer 17 and at the same time is
ruptured from the remainder of paper layer 18 which remains firmly
bonded to layer 17. It is thus apparent that only the area of layer
18 which has been penetrated by the nylon, that is, seal area 14,
is removed from rear wall 12 of the envelope. While not necessary
to the concept of this invention, it has been found that proper
separation of front wall 13 from rear wall 12 is facilitated when
the grain of layer 17 extends transversely across the envelope and
the grain of layer 18 extends longitudinally of the envelope. In
that way there is no danger of tearing layer 17, while layer 18 is
easily torn at the edges of longitudinal heat seal lines 14 and the
heat-sealed portion is stripped from layer 17 to which it is
mechanically bonded. Thus, even if the nylon should penetrate
entirely through layer 18 and slightly into layer 17, the
separation would still readily occur at or just below the boundary
between the two layers. In any event, the nylon penetration would
not be sufficiently deep in layer 17 to cause that layer to tear
through as might occur with a single paper layer.
Although the use of seal chevrons, such as 21, permits the top
corners of the facing walls of the envelope to be easily separated
to start peeling the envelope open as shown in FIG. 4, it is also
desirable to make one wall slightly shorter than the other. This
allows the longer wall to be readily bent away from the other wall
so that both may be grasped for opening purposes. When the walls of
the envelope have been peeled apart for part or all of the length
of the envelope, the enclosed article may be readily removed in any
appropriate way. In this regard, it is well to note that the entire
interior of envelope 11 inward of the heat-sealed areas 14 is
sterile when the envelope is opened, so that the article may be
removed without any danger of coming contact with external surfaces
which may have become contaminated.
A relatively wide range of weights of paper and thicknesses of
plastic film may be used for envelope 11, but the preferable
dimensions are: layer 17 a kraft paper having a weight range of 27
to 33 pounds; layer 18 a kraft paper having a weight ranging
between 3 and 7 pounds; and plastic front wall 13 a nylon film
having a thickness ranging between 0.0005 inch and 0.005 inch. It
is entirely possible that variations from the above preferred
dimensions and materials may be made in constructing envelopes
having the desired characteristics. The only requirement is that
layer 18 be substantially thinner than layer 17 and that plastic
front wall 13 be capable, in response to the application of heat,
of penetrating to a substantial depth in layer 18 to achieve a
secure seal. The fact that thickness variations may occur both in
layers 17 and 18 and in the depth of penetration of the plastic
into the paper layers does not adversely affect any of the
characteristics of this envelope.
FIG. 6 shows an alternate preferred embodiment for the envelope of
this invention. Envelope 22 is formed with an offset chevron seal
23 which may be preferred by some users over the centered chevron
of FIG. 1. This configuration provides two differently shaped
unsealed facing corner flaps which may be separated for purposes of
opening the envelope.
For optimal usefulness, the envelope described herein must be
easily sealable after an article has been inserted so that it may
be filled and sealed "on the job" if desired or by a packaging
company if it intends to provide prepackaged medical and surgical
articles. A relatively inexpensive device which will properly heat
seal end 16 of the envelope is an Audion Impulse Sealer made for
Packaging Aids Corporation of New York City. With this device at
hand, a nurse, after thoroughly cleaning surgical instruments, may
insert them into individual envelopes, heat seal each envelope, and
place a number of the sealed packages into a sterilizer. When the
packages are properly sterilized, the contents are fully protected
and their sterility maintained by the sealed envelope during
subsequent handling and storage. The thus-sorted articles are then
ready for use at a later time without further processing.
Having described preferred embodiments of the invention, various
modifications may be made by those skilled in the art which are
within the scope of the invention described herein. For example,
the end of the envelope to be opened need not have a chevron-shaped
seal but may have only one corner where the seal line is displaced
inwardly.
* * * * *