PLASTIC BAG FOR RECEIVING BLOOD

SACS DE PLASTIQUE POUR RECUEILLIR DU SANG

English Abstract

ABSTRACT OF THE DISCLOSURE
A bag that is suitable for receiving blood from
animals being exsanguinated is made by folding a sheet of
liquid impermeable thermoplastic film back upon itself and
folding down the top edges to form a top portion four sheet
layers thick. An aperture is cut out of the top portion using
a hot die which fuses the four layers together at the perimeter
of the aperture. The handle provided by the aperture is
strong enough to support the bag when filled with blood, and
it also partially closes the bag to reduce the potential for
contamination and spillage.

Claims

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:-
1. A bag comprising a sheet of plastic film folded
back upon itself to form front and back panels and a common
seamless bottom, two marginal edges, and two top edges, with
the top edges being folded down to define a top portion, the
top portion having a grip aperture with all layers of the
top portion being heat sealed together at the perimeter of
the aperture, the marginal edges being heat sealed, and the
upper portion defining a mouth open except for the closure
effected by the heat sealed perimeter of the grip aperture.
2. The bag of claim 1, wherein the front panel is
heat sealed to itself along a band generally parallel to the
top edges, and the back panel is heat sealed to itself along
a band generally parallel to the top edges.
3. The bag of claim 2 wherein the width of each heat
seal band is from one-quarter of an inch to three-quarters
of an inch.
4. The bag of claim 2 wherein the top portion includes
a strip of reinforcing film present in the fold of at least
one of the panels.
5. The bag of claim 2 wherein the section of at least
one of the panels forming the top portion is at least three
layers thick.

Description

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This invention relates to a plastic bag specially
suitable for receiving blood from animals being exsanguinated.
The bag comprises a sheet of water impermeable
thermoplastic film folded back upon itself to form front and
back panels having a common seamle,ss bottom, two marginal
edges, and two top edges. The top edges are folded down to
define a top portion. An aperture suitable for gripping the
bag is formed in the top portion by means of a hot die,
which heat seals the layers of the top portion together at
the perimeter of the aperture. The marginal edges are also
heat sealed together. The top portion defines a mouth which
is open except for the closure effected by the heat sealed
perimeter of the grip aperture.
The invention has generally been described and
will now be referred to more specifically by reference to
the accompanying drawings, illustrating a preferred embodi
ment, and in which:
Figure 1 is a front view of the bag of this invention.
Figure 2 is a sectional view ~f the bag of Figure
1 taken along line 2-2.
Figure 3 is a sectional view of the bag of Figure
1 taken along line 3-3.
The bag has a front panel 10 and a back panel 12
having a common seamless bottom 14. The top edges 16, 18 of
the panels are folded down to define a top portion 20. An
aperture 22 is made by cutting out part of the top portion
20 with a hot die. The temperature of the die is such that,
as it cuts through the top portion 20, it heat seals the
layers of the top portion 20 together at the perimeter 24 of
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the aperture 22. The top edges 16r 18 are shown as folded
to the inside, but they could just as well be folded to the
outside.
To improve the strength of the bag, the number of
layers comprising the top portion 20 can be increased from
four to five by inserting a reinforcing strip of film in the
fold of the front panel 10. Alternatively, instead of
inserting the strip of film, the number of layers of the top
portion 20 can be increased from four to five by increasing
the length of the front panel 10 by the height of the top
; portion 20 and creating another fold so that the top edge 16
extends to the top of the bag, with the result that the
section of the front panel 10 forming the top portion 20 is
three layers thick. To further improve the strength of the ~ ;
bag, the number of layers can be increased to six by doing
the same with respect to the back panel 12.
The front panel 10 and back panel 12 are joined
together at marginal edge 26 and marginal edge 28 by heat
seals.
The front panel 10 is heat sealed to itself along
a band 30 which is generally parallel to top edge 16 and
which extends across the aperture 22 near the lower section
of the perimeter 24. The back panel 12 is similarly heat
sealed to itself. The width of the heat seal band 30 and
the corresponding heat seal band on the back panel is pre-
ferably between one-quarter and three-quarters of an inch.
; The bag is specially suitable for receiving blood
from animals being exsanguinated. Blood is drained into the
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bag through a tube inserted in the opening between aperture
22 and either marginal edge 26 or marginal edge 2g. As the
bag receives the bloodl it is suspended from a support
passing through the aperture 22. An important feature of
the bag is that when it is filled -to capacity with blood, it
may be suspended and carried solely by the handle provided
by the aperture 20 without spillage. The top portion 20 of
the bag provides adequate support and stability, and the
partial closure effected by the perimeter 24 of the aperture
22 reduces the potential for contamination of the blood.
Typical dimensions of a polyethylene bag used for
this purpose are width 18 inches, height 20 inchès, and
nominal aperture dimensions 1.25 by 3.25 inches. The
thickness of the film is preferably 3 mils when the top
portion has five or more layers, and is more than 3 mils, up
to about 4.5 mils, when the top portion is only four layers
thick.
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