Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BACKGROUND OF T~E I~JENTION
This invention relates generally to packages having a
peelable film. Particularly, the present invention relates
to packages wherein a barrier layer or film may be peeled
and separated from a non-i~arrier film and to a method for
packing a product in a pac~age having a peelable barrier
film.
In U.S. Pat. No. 3,574,6~ which issued on Apr. 13,
1971 to Carl Frederick Weinke, a package for a method of
pack.agin~ meats is disclosed. The package includes an inner
oxygen-permea~le mem~er which may ~e gas flushed or
evacuated. The package preserves the freshness of the meat
until the meat is ready to be marketed to the consumer. For
marketing, the outer wrapper is removed and the inner
package is displayed to the consumer. Being oxyq~n-
pcrmeable, the inner wrapper admits oxygen ~o the interior
of the package causing the fresh meat product to change to a
¦ bright red color which the consumer associates with! freshness. ~he inner pouch of the WsinXe package may
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consist~o~ polyethylene ~ilm and the outer pouch may be
cellophane fil~ with a coating of saran (vinylidene chloxide
copolymer.) Another patent showing portions of fresh meat
individually packaged in oxygen permea~le plastic film and
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inserted into an outer contalner of impermeable film is U.S.
Pat. No. 3,681,092 whic~ issued to Oliver R. Titchnell et
al, on Aug. 1, 1972.
Another prior art pac~age is described is U.S. Pat. No.
3,713,849 which issued to Paul E. Grindrod et al. on Jan 30,
197~. In the Grindrod et al. patent a fresh meat pac~age
having an outer oxygen impermeable lamina which is readily
and entirely peelable from an inner oxygen-permeable lamina
is disclosed. The pac.~age includes means for initiating the
peeling separation along an edge of the package. The outer
oxygen barrier main~ains meats in well preserved condition
in spite of the purplish color which has low consumer
appeal. Shortly prior ~o display for sale to the consumer
the outer lamina is removed by the retailer and the product
develops a healthy,,bright red "bloom" due to the high
oxygen through-put of the inner remaining film package. The
material disclosed in Grindrod et al. is a laminate of
PVC/Saran and EVA/Saran. (EVA designates ethylene/vinyl-
acetate copolymer and PVC designates polwinyl-chloride. )
Th~ EVA and PVC la~ers are the inner layers and at the
periphery of the package they are sealed together. The
saran layers can be readily peeled ~rom the respective EV~
or PVC layers with gripping tabs that arQ provided.
Yet another peelable package i5 shown in U~S. Pat. No.
4,055,672 which issued on Oct. Z5, 1977 to Arthur Hir~ch et
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al. In the Hirsch et al. patent a semi-rigid preformed tray
of oxygen imp~rmeable material is formed, a meat product
placed therein, and then thè tray is sealed around its upper
periphery or flange area by a composite lid which has an
inner layer of oxygen permea~le material, an adhesive layer,
and an outer layer of oxygén impermeable material. When the
pac~aye is ready for retail display, in order that oxygen
I can reach the ~resh meat packaged withln permeable material,
¦ the outer, impermeable lid is peeled away so that the oxygen
can penetrate through the remaininy portion of the lid.
In the foregoing Grindrod et al. and Hirsch et al.
patents, a complication arises in that the non-barrier layer
must be sufficiently adhered to the tray member so that
force of removing the barrier layer, especially the force
required to initiate removal of the barrier layer, does not
¦ damage or remove the non-barrier layer.
It is the principal object of the invention to provide
a peelable barrier film pac~age wherein removal of the
barrier film does not adversely affect the non-barrier film
or its seal to-an underlying support or tray member.
Numerous peelable barrier layer pac~ages are prepared
with a co-extrusion or laminating process wherein a formable
composite of the various layers is produced and applied to a
product.
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After removal o~ the barrler layer, the package must b~
marked or tagged by the grocer before it i5 placed in a
display case. It is another object of the invention to
provide a package wherein a label is placed on the non- ~
barrier layer ~etween the two layers so that the label is ~-
exposed upon removal of the ~arrier layer.
It is a further object of the invention to pr~vide a
method for manufacturing a barrier pac~aqe in accordance
with the invention.
other objects and advantag~es will appear hereinbelow.
SUMMARY OF THE INVENTIOM ;~
In accordance with the invention, a peelable barrier
layer pac~age for a product, par~icularly a ~resh red meat
product, comprises a support member supporting the product;
a permeable film means sealed to the support member at a
first seal for enclosing the product; and an impermeable
f'ilm means sealed to the support member at a second seal for
enclosing the permeable film means whereby breaking of the
second seal and removal of the impermeable film means is
accomplished without breaking the first seal.
According to the invention the package is formed by a
method comprising the steps o~ prcviding a support member
having a product supported thereon; sealing a permeable film
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to the support member at a firs~ seal so as to enclose the
product; and sealing an impe~meable film to the support
member at a second seal so as ~o enclose the permeable film,
wher~by breaXing of the second seal and peeling of the
impermeable film means is accomplished without breaking the
first seal.
BRIEF DESCRIPTIOM OF TUE DR~WING5
A detailed description of Freferr~d embodiments of the
invention follows, with reference to the accompanying
drawinqs, ~herein:
Fig. 1 is a cross-section of a package, according to
the invention;
Fig. 2 is an enlarged sectional view of a flan~e of a
package, according to the invention, showing the seals of
¦ 15 the permea~le and imperm~able films;
Fig. 3 is another embodiment of the inventlon, similar
to Fig. 2, and including a tab for initia~ing peel of the
peelable impermeable film, according to the invention;
Fig. 4 is an alternate embodiment similar to Fig. 2;
and
Flg. S is a portion of a packaged top surface of a
product including a label on the permeable film, according
to the invention.
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DETAILED DESCRIPTION
The invention relates to a package for products,
particularly fresh red meat products, ha~ing an inner non~
~arrier film or layer, and a peelable ~uter barrier film or
S layer. .
Fig. 1 illustrates a pac~age 10 in accordance with the
invention. According to the invention, package 10 comprises
a support member 1~ supporting a product 12 and having a
permeable film 16 enclosing the product and sealed to the
support member 14, and a peelable impermeable ~ilm 18 se~led
to the support member 14 and enclosing permeable film 16.
The permeable film 16 is preferably a stretch ~ilm ~pplied
over the product and sealed to the support member 14;
however, the film could be a skin film formed around the
product by vacuum or differential air pressure, that is, a ::
vacuum skin packaging film.
Product 12 packaged in this manner provides fresh red
meat with a longer shelf life while peelable impermeable
film 18 is in place. Impermeable film 18 can be peeled so
that oxygen permeates permeable layer 16 and oxygenates the -
fresh red meat and provides it with a bright red color or
"bloom" for placement in a ret~il display case. The bright
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red "~loom" is desirable as t~e consumer assosiates a bright
red color with freshness.
According to the invention, permeable film 16 is sealed
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to support member 14 through any means known to those
skilled in the art so as to enclose product 12. Preferably,
permeable film 16 is heat séaled to support member 14 around
a periphery of product 12 so that a por~ion 20 of support`-~
mem~er or tray 14 is not covered by permeable film 16.
Imper~eable film 18 is then sealed to support member 14 ;~
around a periphery of the seal ~f permeable film 16 so as to
enclose permeable film 16. Package 10 p~eferably has an -
inner space 15 which is evacuated or flushed with a low
oxygen atmosphere so as to improve the shelf life of ;~
products contained therein.
According to the invention, impe~meable film 1~ and
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permeable ~ilm 16 are sealed to tray 14 in a non-overlapping
~; fashion so that the seal of impermeable film 18 can be
broken and impermeable film 18 peeled ~ithout adversely
affecting the integrity of permeable film 16. Fig. 2 shows
an enlarged portian of tray 14 with im~ermeable film 18 and
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permeable ~ilm 16 sealed thereto.
Tray 14 preferably has upstanding wall portions 22 with
a flange 24 extending outwardly there~rom, pre~erably around
substantially the entire periphery of tray 14. According to
the invention, permeable film 16 is sealed to flange 24 at a
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;~ first seal 26, preferably formed about an inner edge of
flange 24. Impermeable ~ilm 18 is then pre~era~ly applied
over permeable film 16 and sealed to tray 14 at a second
seal 28, pre~erably formed along an outer edge, outside of
first seal 26, so that, advantageously, second seal 28 can
be ~roken for peeling without significant forces being
exerted upon or transferred to the second seal 28.
The sealing of permeable film 16 and impermea~le film
18 is such that first seal 26 defines a .irst perimeter with
tray 14 and second seal 28 de.ines a second perimeter with
tray 14 which is larger and entirely encloses the first
perimeter without overlapping same. In ~his manner, peeling
of impermeable film 18, with the expected force necessary to
breaX seal 28, does not transmit or translate the breaking
force to first seal 26. Seal 26 and permeable film 16 are -
t~erefore left intact on package 10 as desired.
Fig. 3 illustrates a similar embodiment wherein a tab
30 is provided to form a flap 31 ~y which impermeable fi:Lm
18 can be removed from package 10 when desired. Any
suitable tab or other structure may be incorporated so as to
facilitate peeling.
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It is desirable to pr~vide package 10 having a "stretch
wrapped" appearance. In this regard, impermeable ~ilm 13,
as shown in Fig. 4, may be sealed to flange 24 at a bottom
surface 32 thereof. In ~his manner, seal 28a is not visible
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from the tsp and package 10 has the appearance of having
been stretch wrapped. ~ote that in this configuration as
well, seal 28a can be broken and impermeable ~ilm 18 peeled
and removed without damaging permeable film 16.
Permeable film 16 is an oxygen permeable or non-barrier
film or skin which may ~e f'ormable or stretchable material.
T~lpical materials for permeable film 16 include any material
which may ~e securely sealed and bonded to tray 14, such as
ethylene vinyl acetate (EVA), polyethylene film, Surlyn,
stretch olefin film, blown film and the like. Further,
permeable film 16 may be a single or multilayer film having
other layers for numerous other purposes.
Permeable film 16 preferably admits at least about 2000
cc of a gas (oxygen) per square meter of the material per 24
hour period at a temperature of 73 F. This oxygen
permeability or non-barrier characteristic is desirable so
that, when impermeable film 18 is peeled, oxygen can quic~ly
~` ~ permeate package 10 and oxygenate the fresh meat product to
provide the desirable bright red "bloom" associated by the
consumer with freshness.
Impermeable ~ilm 18 may be any suitable barrier or
laminate film which is substantially impermeable to gas such
as oxygen so that a fresh meat product contained in a vacuum
or other atmosphere in package 10 possesses an enhanced
shel~ e over a pac~age without the barrier layer.
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Impermeable film 18 may suitabl~ be for~able or may be
str~tched for application to product 12, and may like~ise be
a si~gle or multi layer film having other layers for other -~ ;
purposes as desired.
Imper~ea~le ~ilm 18 ls preferably substantially
impermeable to gas, especially oxygen, and preferably allows
less than or equal to about 50 cc of oxygen to pass per
s~uare meter per 24 hour period at a te~perature of 73 F.
It is noted that, because i~permeable film 18 is to be
removed prior to display to the consu~e-, the appearance of
impermeable film 18 is not critical. Thus, impermeable film
18 could acceptably be wrinkled, opa~ue, or translucent
without adverse consumer impact. Impermeable film 18 is,
howeverl preferably sufficiently translucent so as to allow
the product 12 contained in package 10 to be identlfied.
Suitable impermeable films for use in the present invention
include ethylene vinyl alcohol copoly~ers, vinylidene ~ -
chloride copolymers, ethylene-vinyl alcohol or hydrolyzed
ethyl/vinyl acetate (EVO~) and others known im the art.
Tray 14 must be a barrier type tray, because package 10
is to be a barrier package. Thus, tray 14 is preferably
laminated or otherwise provided with a barrier film or layer
contained therein for inhibiting the flow of gases through
the tray. Alternatively, tray 14 may itself be provided
from a substantially impermeable material.
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Tray 14 prefera~ly has upstanding walls 22 which are
not as high as the product 12 to be packaged. This allows
films 16, 1~ to be skin wrapped, stretch wrapped or formed
,~ or otherwise intimately wrapped over a top surface 36 (Fig.
~i 5 1) of the product which also provides impxoved consumer
appeal.
Fig. 5 illustrates an alternate emsodiment wherein a
label 34 or tag or the like is disposed between permeable
film 16 and impermeable film 18 for use in properly
labelling product 12 when pac~age 10 is to be displayed for
sale. Label 34 is preferably a~fixed to permeable film 16
so that it remains in placP upon permeable film 16 when
impermeable film 18 is remo~ed.
Product 12 can be packaqed, according to the invention,
by positioning the product on tray 14 or any other suitable
barrier support member. Product 12 may ~e positioned one at
a time on individual trays or may be positioned in rows or
other patterns on sheets of support tray material to be
subsequently cut into individual unit~, all as is known in
the art.
Permeable film 16 is then applied as a stretch film or
ski~ and sealed around the perimeter of product 12 to tray
14 so as to enclose product 12. Excess permeable film
outside of seal 26 is preferably trimmed away to expose the
portion 20 of tray 14, preferably on flange 24, to which the
12
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impermeable film 18 i5 to be seaLed. Label 34 may be
affixed to permeable film 16 if desired. Impermeable film
18 is then seaLed over permeable film 16 to tray 14 at a
seal 28, 28a which is peripherally outside o~ and does not
S overlap seal 26 of permeable film 16. Package 10 ls then
ready for shlpping or sto~ase and, due to the ~arrier layer,
possesses an excellent shelf life.
When pac~age 10 ls to be dlsplayed rOr sale,
lmpermeable film 18 is easily removed without risk of damage
to permeable film 16 or seal 2~. In this manner, package 10
is provided and requires a minimal amount of handling to
provide a package having excellent consumer appeal.
Permeable film 16 and support member 14 define an inner
space 15 of package 10 which, accordlng to the invention,
may be evacuated or flushed with a low oxygen gas before
sealing the permeable ~ilm 16 to the support member 14~ The
low oxygen gas preferably has an oxygen content of less than
or equal to abcut 0.05~ by volume.
It is noted tha~, as is well known in the art, films
16, 18 may suitably 1nclude additional film layers suited to
other specific purposes such as abuse layers, moisture
barrier layers, light barrier layers, and the like.
Thus provided is a pac~age and method for pacXaging
which yields a package having impermeable and permeable
films wherein the impermeable film provides enhanced shelf
life and is easily removable without adversely affecting the
integrity of the inner permeable film.
It i5 to be understocd that the invention is not
limited to the illustrations described and shown herein,
which are deemed to be merely illustrative of the best modes
of carrying out the invention, and which axe susceptible of
modification cf form, size, arrangement of parts and details
of cperation. The invention rather is intended to encompass
all such modifications which are within its spirit and scope
2s defin^d by the c1aims.
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