Note: Descriptions are shown in the official language in which they were submitted.
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PACKAGE
FIELD OF THE INVENTION
The present invention relates to packaging article, more
particularly a stand up pouch for microwaving food
products, particularly liquid food products, in the
package.
BACKGROUND OF THE INVENTION
The amount of time available for preparation of meals has
been steadily diminishing in recent years. Microwave
cooking has been embraced by many consumers as one solution
to the problem of dwindling meal preparation time.
Microwave cooking often demands less attention than
conventional oven cooking and is usually completed in a
shorter period of time.
But it is not enough merely to shorten the amount of time
which must be devoted to cooking. For instance, consumers
would also prefer not to have to expend effort washing or
cleaning the microwave at the completion of microwave
cooking, to the extent that this can be avoided. There is a
need, therefore, for microwave packaging which can meet a
variety of consumer needs, including easy opening and
minimization of time spent cleaning the microwave.
Numerous microwavable containers have been disclosed over
the years.
Johnson et al. EP 823 388 (Kraft) discloses a stand up
pouch for a microwavable food entree. Notch 23 may be
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included to facilitate initiation of the opening procedure.
Hughes et al., U.S. Published Patent Application No.
US2004/0118839 relates to a stand up pouch that is a
convenient vehicle to eating, which uses a single partial
tear for venting. Igota, et al., US Patent No. 6,121,597,
discloses a notched bag for microwave ovens capable of
allowing escape of vapor generated during microwave heating
using joints of different weaknesses.
Chow, et al., US Published Patent Application No
2002/0068668, discloses a method for producing an easy
open, easy tear package using a laser. A microprocessor
modulates the laser to create tear initiation areas along a
score line.
Tang, US Published Patent Application No. 2002/0001645, is
directed in Fig. 12 to a package made from an ACE sheet and
an inner layer. The ACE sheet has nicks on each of two
lines of weakness to permit sequential opening of three
compartments. In the embodiment of Fig. 9j, prior to
microwave cooking, the consumer tears the bag open along
lines of weakness 34 to create a small opening allowing
partial release of gas vapor during cooking. Following
microwave cooking, the bag may be opened using further
aligned lines of weakness 45. The further aligned lines of
weakness 45 may extend substantially parallel to the lines
34, no greater than 15 mm apart.
None of the references create a tortuous path for venting
as a means of guarding against splatter in the microwave,
thereby being particularly useful for microwave heating
liquid food products.
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SUMMARY OF THE INVENTION
The present invention is directed to a new microwavable
package having a seal so configured as avoid splatter of
the product during heating or cooking in the microwave,
thereby avoiding the need for the microwave to be washed
after heating or cooking. The package is designed to permit
venting of the package during cooking while minimizing the
possibility for a messy and inadvertent escape of product
onto, for example, the floor and walls of the microwave.
The seal system sets up a tortuous path for vapors from
food products, particular liquid food products, to travel
during venting.
The package comprises a bottom end and a top end and first
and second side wall ends extending between the bottom and
top ends. A top seal is provided along the entire top end
to seal the package for storage of a food product. A
splatter guard seal is situated a sufficient distance below
the top end, spanning from the first side wall end
approximately half way along and parallel to the top end.
A tear area is provided which instructs cutting of at least
a portion of the top end and of the first side wall.
Removal of a portion of the top end along the tear area
assists cooking of the package contents by permitting
release of pressure accumulated within the package due to
elevated temperatures. However, after the original top end
is torn off, the splatter guard seal creates a tortuous
path between the opening at the torn top end and the food
contained within the package such that the chances of
spattering of the product during cooking are essentially
eliminated. The second partial seal, i.e., the splatter
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guard, prevents liquid food from splattering during
microwave cooking.
Since a purpose of the dual seal is to permit the food to
be cooked without splattering into the microwave, there
will generally be a vertical distance between the seals,
preferably one inch, especially at least 0.25 inch, and at
most one and one half inches when the height of the pouch
is 6 to 7 inches. The important thing is that the dual
seals have an adequate vertical distance between them and
that their configuration creates a tortuous path, so that
the goal venting without spilling is achieved.
Optionally, but preferably, a label or graphics are
provided on the pouch to indicate to the consumer where the
pouch should be cut prior to cooking.
The pouches may be sealed using a variety of techniques
known in the art, including for example by way of laser
sealer or ultrasonic sealer.
Preferably, the package is a microwavable stand up pouch
which, when food is contained therein, can be rested on the
bottom end on a tabletop or other flat surface with the
opening at the top. Typically the package will be a
flexible package comprised of a microwavable material,
preferably lamination containing polyethylene,
polypropylene, polyester and/or nylon.
For a more complete understanding of the above and other
features and advantages of the invention, reference should
be made to the following detailed description of preferred
embodiments and the accompanying drawings.
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BRIEF DESCRIPTION OF THE DRAWING
Fig. 1 is a cross sectional view of a pouch, after sealing,
5 according to the present invention;
Fig. 2 is a perspective view of the pouch of Fig. 1 filled
with food product.
DETAILED DESCRIPTION OF THE INVENTION
The package of the invention will generally be made of
flexible packaging, e.g., thermoplastic, and will typically
take the form of a bag or pouch. The package material may,
for instance, be a reverse printed multi-layer lamination
such as one comprising a layer of polyester and a layer of
polypropylene.
With reference to Fig. 1, pouch 10 is prepared by placing
two layers of the packaging lamination one atop the other,
or folding a single layer, and sealing along the sides to
provide first side wall end 12 and an opposing second side
wall end 14 and side sealing margins 31, 32, respectively,
and along the bottom end 34 to provide bottom sealing
margin 24. Sealing may be effected, for example, by heat
sealing, using laser or ultrasonic techniques for example.
Areas of sealing prior to filling of the pouch are along
these margins, leaving top end 30 open. Sealing margins 31,
32 may have a variety of cross sectional shapes, e.g.,
rectangular, triangular, circular, oval, etc.
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Bottom end 34 is preferably provided with a gusset or other
arrangement (not shown) at bottom end 34 to promote
standing up of the pouch when it is filled with food, as is
known in the art. In this way, once the package has been
filled, it can be rested by means of bottom end 34.
Prior to filling, pouch 10 is typically open only at top
end 30 for filling, followed by sealing with the dual
sealer according to the present invention. After pouch 10
is filled with microwavable food product 26, it is sealed
continuously along the upper edges of the sheets at upper
end 30 of the pouch to form upper seal 18. A second seal,
splatter guard seal 20 is provided an effective distance,
preferably 1 inch, below upper seal 18, running parallel to
seal 18 from first side wall 12 but only partially along
the width of the pouch. Preferably, splatter guard seal 20
spans 0.50 the width of the package or less, such as 0.25
to 0.75 the width of the package.
Side sealing margin 31 is on side 12 has an end of the
pouch which is to be cut open prior to microwave heating,
referred to as tear area 22. optionally, but preferably, a
label or graphics (not shown) are provided on pouch 10 to
indicate to the consumer where pouch 10 should be cut prior
to cooking. The label or graphics denote tear area 22
which promotes cutting of only a portion of top wall 30 of
pouch 10 to create opening 23 for venting and subsequently
for dispensing liquid food product. Cutting may be along a
single line to remove a substantially triangular section,
as shown in Fig. 2, or along two substantially
perpendicular lines to remove a substantially rectangular
area, as denoted by dotted lines in Fig. 1.
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In use, when ready to microwave the product, a consumer
cuts the pouch along tear area 22, removing only a portion
of top end 30 of pouch 10 to create opening 23. Opening 23
permits pouch 10 to vent while it is being microwaved.
However, after the original top end is torn off, the
splatter guard seal 20 creates a tortuous path 28(shown by
the arrow in Fig. 2) between the opening at the torn top
end and the food contained within the package such that the
chances of spattering of the product during cooking are
essentially eliminated. The tortuous path for venting
vapors, indicated with an arrow in Fig. 1. When cooking is
completed, the pouch is removed from the microwave and then
the food product is allowed to be fed by gravity to exit
from pouch 10 through opening 23.
Suitable microwave ovens will typically operate at powers
of 800 Watts to 1200 Watts.
Although not limited by size, preferred pouches according
to the present invention will hold 5 weight oz to 15 weight
oz of product, with most preferred capacities being 8 oz
and 13.5 oz weight sizes. Although not limited by fill
methods, preferably, product is filled to 0.75 of the full
volume capacity of the pouches.
EXAMPLES
EXAMPLE 1
For all the examples, a 1000 W microwave was used. Pouches
were filled to about 0.75 of full capacity.
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Pouch 10 according to the present invention was filled with
product, sealed with top seal 18 and splatter guard seal
20. Pouch 10 was then cut along tear area 22 and heated
with product inside in a microwave on high for 90 seconds.
No splatter was observed.
EXAMPLE A
A pouch having the same dimensions as that of Example 1 was
provided, except that the splatter guard seal was not used.
The pouch was then cut along a tear area as in Example 1.
When heated in the same microwave with the same amount of
the same product, food splattered onto the microwave floor
and/or walls within 90 seconds of heating on high.
EXAMPLE B
A pouch having the same dimensions as that of Example 1 was
provided, except that the splatter guard seal was not used
and the pouch was cut along the entire width of the top
end. When heated in the same microwave with the same amount
of the same product, food splattered onto the microwave
floor and/or walls within 90 seconds of heating on high.
Example 1 and comparative Examples A and B demonstrate how
essential the splatter guard is for avoiding soiling of the
microwave.
The term "comprising" is used herein in its ordinary
meaning and means including, made up of, composed of,
consisting and/or consisting essentially of. In other
words, the term is defined as not being exhaustive of the
steps, components, ingredients, or features to which it
refers.
