U.S. patent number 3,615,711 [Application Number 04/794,307] was granted by the patent office on 1971-10-26 for package for storing and heating food and method of forming same.
This patent grant is currently assigned to National Biscuit Company. Invention is credited to Joseph Markus, James H. Rowe, John B. Sortor.
United States Patent |
3,615,711 |
Markus , et al. |
October 26, 1971 |
PACKAGE FOR STORING AND HEATING FOOD AND METHOD OF FORMING SAME
Abstract
A package for containing and storing food and heating the
contained food in a toaster including a top margin folded upon
itself at least twice, a longitudinal margin folded upon itself and
flattened to the package to form a longitudinal fold line, and a
tear notch aligned with the longitudinal fold line whereby the
package may be vented by tearing through the top margin on the
longitudinal fold line from the tear notch and the food may be
readily removed after tearing the longitudinal fold line by pulling
the longitudinal margin from the top to the bottom of the package.
A method of forming the package including spacing food portions
along a strip of sheet material, folding the sides of the sheet
material over the food portions, forming the longitudinal margin by
sealing the side edges of the strip and folding the longitudinal
margin upon itself, sealing the strip at areas between food
portions, severing the strip to form top and bottom margins,
folding the top margin upon itself twice, and cutting a tear notch
at the top margin.
Inventors: |
Markus; Joseph (Hicksville,
L.I., NY), Rowe; James H. (New Hyde Park, L.I., NY),
Sortor; John B. (Oakland, NJ) |
Assignee: |
National Biscuit Company (New
York, NY)
|
Family
ID: |
25162285 |
Appl.
No.: |
04/794,307 |
Filed: |
January 27, 1969 |
Current U.S.
Class: |
426/110; 426/107;
383/200; 426/113; 383/103 |
Current CPC
Class: |
B65D
75/52 (20130101); B65D 81/3492 (20130101) |
Current International
Class: |
B65D
81/34 (20060101); B65D 75/52 (20060101); B65d
081/34 () |
Field of
Search: |
;99/171H,171LP,171M,174,171 ;229/3.5,66,51IS |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
509,364 |
|
Mar 1952 |
|
BE |
|
797,651 |
|
Oct 1968 |
|
CA |
|
Primary Examiner: Lutter; Frank W.
Assistant Examiner: Mentlik; William L.
Claims
I claim:
1. A sealed package, for storing food and heating the food by
insertion into a toaster, formed of pliable, heat-resistant,
tearable, thermally conductive, nonporous sheet material enclosing
said food; a sealed top margin for said package, said sealed top
margin being folded upon itself to form a top fold line, said
folded top margin being of such length as to yield upon unfolding a
handling tab which extends out of the toaster; and a tear notch in
said folded top margin at a point on said top fold line
intermediate the sides of the package whereby the package may be
vented by tearing through said folded top margin at said tear notch
to divide said folded top margin into two portions and whereby said
extended handling tab is formed by unfolding one of the portions to
facilitate insertion and removal of the package from the
toaster.
2. The package as claimed in claim 1 wherein said package and said
folded top margin are formed from a single sheet of said sheet
material having an upper edge, a lower edge and two side edges,
said sheet being folded upon itself to form a front panel and a
rear panel by aligning said two side edges and causing said upper
and lower edges to be folded upon themselves, said lower edge being
sealed to form a bottom margin, said upper edge being sealed to
form said folded top margin, and said two side edges being sealed
to form a longitudinal margin.
3. The package as claimed in claim 1 wherein said sheet material is
formed with a sealed longitudinal margin disposed intermediate the
sides of the package, said longitudinal margin being folded upon
itself and flattened against said package to form a longitudinal
fold line along the entire length of the package, and said tear
notch is aligned with said longitudinal fold line whereby the
package may be accurately vented by tearing through the top margin
on said longitudinal fold line and subsequently opened by
continuing the tearing through the entire length of the
package.
4. The package as claimed in claim 3 wherein said longitudinal
margin is flattened against that portion of said top margin that is
adapted to be unfolded to present an extended handling tab.
5. The package as claimed in claim 3 wherein a hole is cut through
said top margin in alignment with said longitudinal fold line and
said tear notch whereby said hole may be used to support the
package on a hook or rod without substantially weakening the
structure of the package.
6. A method of packaging food in pliable, heat-resistant, tearable,
thermally conductive, nonporous sheet material comprising the steps
of placing measured portions of food in spaced relation on a strip
of the sheet material; folding the strip of sheet material over the
portions of food until the side margins of the strip of sheet
material meet in inner face to inner face relationship to form a
rear panel; sealing the side margins of the strip of sheet material
to form a longitudinal margin; folding the longitudinal margin upon
itself; flattening the folded longitudinal margin to the rear panel
to form a longitudinal fold line; sealing the strip of sheet
material in the spaces between food portions; severing the strip of
sheet material in the sealed spaces to provide a top margin for a
first package and a bottom margin for a second package adjacent to
first package; folding the top margin upon itself at least once;
and cutting a tear notch in the top margin aligned with said
longitudinal fold line.
7. The method as claimed in claim 6 wherein the top margin is
folded upon itself twice.
8. The method as claimed in claim 7 including the step of cutting a
hole through the top margin in alignment with the tear notch and
the longitudinal fold line.
Description
BACKGROUND OF THE INVENTION
The present invention pertains to food packages and more
particularly to convenience food packages for storing and cooking
food without removal from the package.
Some dry foods, such as rice, flour, sugar etc., which are not
adversely affected by exposure to air have been packaged for both
storage and transportation in containers, such as cardboard boxes
and paper bags, which provide protection from moisture and foreign
matter. In the past foods that require protection from air have
been either canned or, more recently, packaged in flexible
containers that do not have the disadvantages of cans which are
relatively heavy, bulky, rigid and of fixed shape.
With the advent and popularity of frozen foods, flexible packages
have become more or less a necessity in that they permit maximum
utilization of freezer space and the packaging of foods of varying
shapes and sizes. They also are more convenient to handle during
preparation and heating. These advantages have made flexible
containers popular for a wide variety of foods. However, flexible
packages have not reached their full potential because they have
not as yet efficiently eliminated the inconvenience of placing the
package containing the food, or first removing the food from the
package and placing it, in suitable cooking pots or pans, heating
or cooking on a stove or in an oven and measuring out portions
before serving. This procedure consumes a large amount of time and
even more time is wasted in the cleaning of heating or cooking
equipment such as stoves, ovens, pots, and pans after use.
Moreover, misjudgment in the amounts of prepared food needed
results in too much food leftover or not enough. Misjudgments in
the amount of each serving also results in wasted food which is
left uneaten.
These problems are of considerable importance in the restaurant and
institutional industries including airlines, cafeterias, hotels,
motels, hospitals, drug stores, department stores, vending
machines, clubs, schools and the like since it is desired to serve
food to large numbers of patrons or patients in a minimum of time
with a minimum of effort and manpower.
The armed services are faced with similar problems where large
numbers of people are served meals. The problems are further
multiplied by the wide range of tastes of patrons or patients
further increasing the size and number of cooking equipment to be
used, the amount of cleanup time and effort needed and the amount
of wasted food.
Similar problems, on a smaller scale, however, are faced in the
home and the intensity of the problems varies with the size of the
family. There is great interest for the housewife in eliminating or
reducing food preparation and cleanup time and effort.
In small families or with persons living alone it is very difficult
if not impossible to purchase food for preparation in single
serving portions or even two or three portions. For such families
or persons leftovers are inevitable. Elderly people and others who
are concerned with their diet have difficulty in controlling the
size of servings consistent with their dieting needs or
objectives.
Members of most families have different likes and dislikes in
foods, thus adding to the feeding problems of the housewife and
potential waste because of leftovers and spoilage. Families having
infants or small children who are not able to consume the usual
family menu repeatedly face the problem of leftovers and potential
spoilage of baby foods. Busy families whose members have different
schedules are on the increase in our way of life and present
problems to the housewife in serving adequate nourishment to the
family in appetizing form.
As an example, meats tend to be both the highest cost and most time
consuming element of at-home meals. The housewife probably spends
more time in preparing meats and in cleaning up after preparation
of meats than any other food. Yet very little has been done to
provide modern convenience and effective economy in the meat
category. There is every indication of a great demand by the
housewife as well as institutions, restaurants and other food
servers for a high quality, precooked, portion-controlled, easily
stored ready to heat-and-eat packaged meat product as well as other
food servings such as soups, sauces, gravies, vegetables, rice and
all other kinds of cooked or heated table foods.
In the past packages have been designed with the object of both
storing and cooking relatively small measured portions of food
therein. However, none of these packages have in practice proved
adequate in eliminating or reducing the problems connected with
food preparation while also providing a container that may be both
economically formed and sufficiently rigid and sturdy to withstand
the punishment concomitant with the purveying of food which
includes handling by the producer, transporter and server.
Some disadvantages of prior packages for both storing and cooking
food are that such packages have a considerable tendency to tear to
permit air to enter and spoil the food. Also, prior packages have
not been formed in such a manner as to facilitate handling without
unduly damaging the package and because of their structure the
venting of such packages for cooking or heating cannot be easily
and precisely accomplished. The removal of food from the prior
packages has been difficult and because of the fragile and easily
tearable nature of the metallic foil used in the construction of
such packages structural sturdiness has not heretofore been
achieved. In addition, the prior packages have been designed for
specific foods rather than having a universal design capable of
containing a large variety of foods.
U.S. Pat. Nos. 2,609,301 to Lindsey, 2,633,284 to Moffett et al.,
2,807,550 to Zarotschenzeff et al., 2,881,078 to Oritt, 2,912,336
to Perino, 3,117,875 to Burns et al., 3,132,029 to Beck, 3,185,372
to Gerraro, 3,322,319 to Sweeney et al., and 3,361,576 to Jacobsen
disclose packages for storing food and cooking food in the packages
in toasters; however, the packages disclosed in these patents all
suffer from one or more of the above mentioned disadvantages. For
instance, none of these patents disclose a package that is both
compact and yet can be rendered readily accessible in a toaster.
None of these patents have overcome the main problems concomitant
to packages made of metallic foil, namely, its propensity for
undesired tearing, puncturing and mutilation and, in practice, none
have proved adequate in eliminating or reducing the problems
mentioned above.
Specifically, it is desirable to package foods such that
conventional electric toasters can be utilized for cooking or
heating and such that the portions of food therein are
individualized.
The toaster is one of the most common, least expensive and probably
least used appliances in home, commercial and institutional
kitchens. Almost every kitchen has one or more. The toaster also is
one of the easiest heating appliances to operate and maintain and
very seldom requires cleaning. As such it provides an almost ideal
implement of convenience in "instant" meal preparation.
SUMMARY OF THE INVENTION
The present invention is directed to food packages and methods for
making same providing a practical system for storing an almost
unlimited variety of cooked, partially cooked and uncooked foods in
measured or controlled portions, such as individual servings, for
prolonged periods of time while maintaining nutritional values and
in a form which permits rapid and convenient preparation and
serving with little or no loss of tastiness, flavor and freshness.
Unlike most packaging systems currently in use, the invention
provides unitary food packages containing measured or controlled
portions which can be individual servings or low multiples of
individual servings. The invention also admits of merchandising a
wide variety of foods, for example, in combination packs of
individual foods making up a balanced meal which can be fully
prepared solely through the use of any conventional toaster.
Illustrative of foods which can be packaged in accordance with the
present invention are beef burgundy, hamburgers (seasoned and
unseasoned), pizza burgers, beef stew, beef stroganoff, corned beef
slices, boneless short ribs of beef, hickory smoked beef slices,
roast beef slices (with and without gravy), barbecued beef, ham
slices and steaks, chicken slices, turkey slices, meat loaf (with
and without gravy), veal parmesan, veal cutlet (breaded and
otherwise), chicken fried steak, meat balls, meat balls in
spaghetti sauce, Swedish meat balls, Salisbury steak (with or
without onions) lamb chops, Swiss steak, beef steaks, pork chops,
fish, breaded filets, mushrooms (with and without gravy), gravies
(chicken, brown, beef, etc.), sauces (white, hollandaise, barbecue,
etc.), stuffings (turkey, meat, bread, etc.), cocktail franks,
corn-muffins, dinner rolls, spaghetti sauce, spag O's with
meatballs, shrimp fried rice, chicken chow mein, tamales, chicken
a-la king, chicken fricassee, Manhattan clam chowder, New England
clam chowder, chili, ravioli, sloppy Joe, beef gravy, cream corn,
sweet peas, chocolate fudge sauce, fried clams, clam sticks, fish
sticks, shrimp cakes, shrimp marinara, sweet sausage and peppers,
instant mashed potatoes, instant sweet potatoes, egg rolls,
stuffing, rice, garlic bread, soup (dehydrated), coffee, baby
foods, hot chocolate, cereals, tea, pet foods, hot gravies for pet
foods, pie fillings, custards, toppings (chocolate, butterscotch,
etc.), desserts (puddings, etc.), vegetables (with and without
sauces, butter, etc.).
These foods, especially the meats, are preferably fully prepared,
precooked and frozen requiring only thawing and reheating prior to
serving. In this connection it has been unexpectedly found that the
toasting times and temperatures characteristic of conventional
toasters are fully adequate for thawing and adequately reheating
frozen foods to temperatures which are high enough for serving and
eating. Foods that are amenable to storage without freezing or
refrigeration, of course, need not be frozen or refrigerated but
simply stored on the shelf in the packages of this invention.
Cereals, dehydrated soups, hot chocolate powders, tea and other
shelf stable foods fall into this category. Also, those foods which
are of the instant type requiring only the addition of hot water
and those foods which require only a small amount of cooking time
need not be precooked. Cereals, rice, hot chocolate powders and tea
fall into this category.
The present invention drastically reduces the time, effort and
manpower needed for the preparation and serving of meals. It
substantially eliminates the need for measuring out portions, since
each package contains a controlled amount of food. It permits a
wide range of selectivity for serving a wide variety of personal
tastes at one sitting with almost no extra effort and in a minimum
amount of time. It also permits more precise control of food intake
without wastage for those concerned with diet and allows the
preparation of single meals which are well balanced for those who
live alone. It substantially eliminates leftovers and cuts cleanup
time to a minimum. Cleaning of cooking equipment is obviated, since
no pots and pans are used and the package after use is simply
discarded. The only heating appliance used is the conventional
toaster which, with a minimum of care, is not dirtied. The present
invention permits an ultimate of convenience in the preparation of
full, well-balanced, appetizing meals without any expenditures for
expensive heating or cooking equipment.
The packages of the present invention are not only useful in the
home but find extensive utilization in commerce in restaurants,
hotels, clubs, cafeterias, vending machines, snack bars, lunch
counters, food stands, in hospitals, nursing homes, prisons,
schools, colleges, in the armed services, employees cafeterias, and
in any kitchen whether private, commercial or institutional.
Specifically, it is an object of the present invention to construct
a package for storing and cooking foods that is pliable yet resists
tearing and mutilation.
Another object of the present invention is to construct a package
for storing and cooking foods in a toaster having a thickened top
margin to resist tearing and facilitate handling.
A further object of the present invention is to provide a handling
tab for a package to facilitate the cooking of food in a toaster
such that, when the package is in use, the handling tab extends
above the toaster to facilitate insertion into and removal from the
toaster, but, during shipping, handling and storage prior to use,
the handling tab is folded down or in a retracted position where it
is protected from mutilation or damage.
The present invention has another object in that a package for
storing and cooking food may be constructed of a single sheet of
pliable, heat resistant, thermally conductive, nonporous sheet
material folded upon itself and has a folded longitudinal margin
and a folded top margin to provide configuration strength for the
package.
Another object of the present invention is to utilize a
longitudinal sealing margin having a longitudinal fold line
associated therewith in alignment with a tear notch provided in a
transverse sealing margin of a package to provide precise venting
of the package for cooking and to provide a well-defined tear line
which facilitates opening and removal of food from the package
after cooking.
A further object of the present invention is to provide a method
for packaging food in pliable, heat resistant, thermally
conductive, nonporous sheet material such that food portions may be
individually packaged with the use of only three seals, two of
which are folded to provide thickened margins.
The package of the present invention is advantageous over
previously known packages in that the package is tear resistant due
to a thickened top margin, the package can be economically formed
from a single sheet of material, the package retains its
configuration due to the cooperation of a thickened longitudinal
margin and a thickened top margin, the package is easily and
precisely vented for cooking, food may be easily removed from the
package after cooking, and utilization of the package with
conventional toasters is facilitated by the provision of a handling
tab which is in a protected position during shipping and storage
but is extended when the package is prepared for heating.
The present invention is generally characterized in a package for
storing food and heating the food by insertion into a toaster
comprising a pouch of pliable, heat resistant, thermally
conductive, nonporous sheet material, a sealed top margin for the
pouch being folded upon itself and a tear notch cut in the top
margin intermediate the sides of the package to facilitate venting
of the package and to provide, after manipulating a portion of the
top margin, a handling tab for insertion and removal of the package
from the toaster. The present invention is further generally
characterized in a method of packing food in pliable, heat
resistant, thermally conductive, nonporous sheet material
comprising the steps of spacing food portions on a strip of the
sheet material folding the sides of strip of sheet material over
the food portions, sealing the side edges of the strip to form a
longitudinal margin, folding the longitudinal margin upon itself,
flattening the longitudinal margin, sealing the sheet material in
the spaces between the food portions, severing the sheet material
in the sealed spaces to provide a top margin and a bottom margin,
folding the top margin upon itself and cutting a tear notch in the
top margin.
The apparatus shown and described in Griner patent U.S. Pat. No.
3,402,524 and the method shown and described in Griner patent U.S.
Pat. No. 3,403,033 with modification are available for the
low-cost, automatic mass-production of filled food packages of the
present invention. Also, the conveying, collecting and metering
method and apparatus shown and described in Griner patent U.S. Pat.
No. 3,402,803 with modification are available for handling and
packing the filled food packages of this invention. It can be
readily seen that the methods, apparatus and technology are
available for producing, handling and packing the filled food
packages of this invention at high rates of production and low
cost.
Further objects and advantages of the present invention will become
apparent from the description of the preferred embodiments as shown
in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation of a package constructed in accordance
with the present invention;
FIG. 2 is a rear elevation of the package of FIG. 1;
FIG. 3 is a front elevation of a modification of the package of
FIG. 1 having a different configuration for the heat absorptive
area;
FIG. 4 is an enlarged, broken view of the sheet material utilized
in the construction of the packages of the present invention;
FIG. 5 is a simplified perspective view illustrating the steps of
forming packages according to the present invention;
FIG. 6 is a sectional view of a partially formed package taken on
line 6--6 of FIG. 5;
FIG. 7 is a sectional view of a partially formed package taken on
line 7--7 of FIG. 5, illustrating the first fold of the
longitudinal margin;
FIG. 8 is a sectional view of a partially formed package taken on
line 8--8 of FIG. 5, illustrating the second fold of the
longitudinal margin;
FIG. 9 is a sectional view of a partially formed package taken on
line 9--9 of FIG. 5, illustrating the flattened longitudinal
margin;
FIG. 10 is a sectional view taken on line 10--10 of FIG. 5,
illustrating the manner of severing the individual packages;
FIG. 11 is a sectional view taken on line 11--11 of FIG. 5,
illustrating the first fold of the top margin;
FIG. 12 is a sectional view of a partially formed package taken on
line 12--12 of FIG. 5, illustrating the second fold of the top
margin;
FIG. 13 is a sectional view of the completed package taken on line
13--13 of FIG. 5;
FIG. 14 is a rear elevation of the package after venting the top of
the package;
FIG. 15 is a rear elevation of the package after the unfolding of a
portion of the top margin to form a handling tab; and
FIG. 16 is a rear elevation of the package showing the longitudinal
fold partially torn downwardly in the process of opening the
package.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A package 20 according to the present invention is shown in front
elevation in FIG. 1 and in rear elevation in FIG. 2 and includes a
sealed top margin 22 and a pouch including a sealed bottom margin
24 and a sealed longitudinal seam or margin 26. Package 20 is
formed of a single sheet of material folded upon itself to form a
front panel 28 and a rear panel 30 with the upper portions of the
inner faces sealed together to form top margin 22, the lower
portions of the inner faces sealed together to form bottom margin
24 and the side portions of the inner faces sealed together to form
longitudinal margin 26.
As will be described in more detail hereinafter, top margin 22 is
advantageously folded upon itself twice. The increased strength of
the top margin 22 due to the double fold permits it to be used as a
grip or handle to decrease the chance of tearing or mutilation of
the package during handling, and also permits the package to be
stored on a hook inserted through a hole 32 through the center of
top margin 22 without the danger of damaging or seriously weakening
the package. When cooking or heating the contents of the package,
it is desirable to permit the inside of the package to communicate
with the atmosphere to release internal pressures which tend to
build up during heating. Thus, a tear notch 34 is cut at the top
fold line 35 of top margin 22 to indicate where the package should
be vented and to aid in tearing the material in a straight line
just through the lower edge of the top margin 22 to provide the
small vent required.
Bottom margin 24 is sealed in face-to-face relationship and need
not be folded since handling and storing may be accomplished
through top margin 22.
Longitudinal margin 26 is folded twice, as will be described in
more detail hereinafter, to give longitudinal strength to the
package, to provide a guide for venting, and to provide a simple
and effective tear strip to facilitate opening the package and
removing the contents.
An example of a pliable, heat resistant, tearable, thermally
conductive, nonporous material suitable for use with the present
invention is illustrated in FIG. 4 and includes an outer layer 36
consisting of a coating of dark colored epoxy resin approximately
one ten-thousandth of an inch in thickness, bonded to an internal
layer 38 of a coating of dielectric material having a thickness of
approximately two ten-thousandths of an inch. The internal layer 38
is bonded to a base layer 40 of metallic foil having a thickness of
approximately fifteen ten-thousandths of an inch, and an inner
layer 42 bonded to layer 40 of heat sealable material approximately
one ten-thousandth of an inch in thickness.
Especially preferred as the metallic foil is aluminum foil which
can be used in the thickness given above or in thicker or thinner
sizes as desired or required for specific applications. Stainless
steel foil is also available and can be used if desired.
Substantially any heat-conductive sheet material can be used as
layer 40. For example, heat-resistant plastic films, such as Mylar,
having thin coatings of vapor deposited metals are useful. Also,
plastic films formed with substantial amounts of metallic particles
dispersed throughout are also useful.
The dielectric layer 38 is for the purpose of electrically
insulating the package in the event of contact with the heating
elements of the toaster. Substantially all thermosetting plastics
and high heat-resistant thermoplastics in the absence of
electrically-conductive additives are dielectrics or electrically
insulative and any suitable thermosetting or high heat-resistant
thermoplastic can be used. For example, epoxy resins similar to
layer 36 can be used. Phenolic resins, melamine-formaldehyde
resins, urea-formaldehyde resins and polyester resins are examples
of suitable resins that can be employed in making layer 38.
The inner heat-sealable layer 42 comprises a transparent,
heat-activatable adhesive, for example, a thermoplastic material
having softening temperatures above those temperatures usually
encountered in an electric toaster, for example, above about
500.degree. F. The layer 42 is transparent so that the shiny,
reflective inner surface of base layer 40 is preserved.
High-melting polyester resins, vinyl chloride resins, vinyl
chloride-vinyl acetate resins, polyacrylic resins and the like can
be employed. When thermoplastic materials are used in any of layers
36, 38 or 42, such materials should not melt or soften to any
undesirable extent at temperatures normally encountered in toasters
and preferably not below 500.degree. F.
Any type of lettering or designs such as labels, instructions,
trademarks, etc. may be placed on the front and rear panels of the
package. The outer layer 36 which, for example, may be formed of
dark blue epoxy which is primarily heat-absorptive may be
over-printed with various patterns of white which is primarily
heat-reflective to control heat absorption and distribution inside
the package in accordance with the heating requirements of the food
product contained in the package.
For example, in FIGS. 1, 2 and 3, those portions above line 44 are
of a dark color such as dark blue and those portions below line 44
are of a light color, such as white. Although heated air rises, a
sizable proportion of heat escapes from the mouth of the toaster by
radiation or convection currents such that temperatures in the
lower portions of the conventional upright toaster tend to be
considerably higher than temperatures near the mouth. The same
considerations apply to horizontal toasters to the extent that
temperatures deep within the toaster cavity tend to be much higher
than the temperature near the mouth. In addition, the temperatures
of the central portions of a toaster pack in a toaster tend to be
higher than those portions adjacent the side edges. In order to
obtain as uniform a temperature as possible throughout the package
for the purpose of more uniform heating or cooking of the contained
food, it is preferred that the primarily heat-reflective, e.g.,
white, pattern extend centrally upwardly from the bottom portion of
at least one of the panels of the package as best shown in FIGS. 1
and 3. The temperatures of the lower corner portions of the package
also tend to build up because of proportionately greater surface
area per local contained volume exposed to radiation and the higher
temperatures and lower rate of heat loss in the depths of the
toaster cavity. Thus, in order to maintain a more even temperature
distribution in the lower corner areas, they too are preferably
light colored, e.g., white, as illustratively shown in FIGS. 1 and
3. The light, primarily heat-reflective areas which extend upwardly
on the sides and in the center of the panel are preferably tapered
upwardly as shown in FIGS. 1, 2 and 3 to correspond to the
temperature gradient in the toaster cavity. The upwardly extending
tapered, primarily heat-reflective areas can be truncated with
primarily heat-absorptive areas as shown in FIG. 3, if desired, at
any desired point to result in a higher temperature in the
truncated areas.
As shown in FIG. 2, the longitudinal fold 26 is coated almost
substantially completely with a primarily heat-absorptive coating
to enhance penetration of heat through the fold.
A method of forming package 10 with a food product therein is
illustrated in FIG. 5, and it should be clear that while a pattie
46 such as hamburger or sausage is illustrated the method can be
used with any food to be packaged.
A flat strip 48 of sheet material, such as the material illustrated
in FIG. 4, is conveyed in the direction of the arrows, and a
plurality of patties 46 or other portions of food are disposed
thereon and are spaced from each other to leave a sufficient amount
of the strip 48 therebetween to form top margin 22 and bottom
margin 24. A pair of heated rollers 50 and 52 are mounted above the
strip 48 and patties 46 at a suitable distance to permit a double
thickness of strip 48 and patties 46 to pass thereunder. To
commence the packaging operation the side edge portions of material
48 are threaded between heated rollers 50 and 52 which operate to
heat and press the side edge portions together in a face-to-face
relationship. The heat aided by pressure activate the inner layer
42 to seal the side edge portions together.
The bottom of strip 48 ultimately forms the front panel 28, as best
shown in FIGS. 6 through 9, and the rear panel 30 is formed from
the two folded over sides 54 and 56. The longitudinal side edge
portions of the folded over sides 54 and 56 are sealed in
face-to-face relation at right angles to rear panel 30 to form a
flange 58, best shown in FIGS. 5 and 6, as the first step in
forming longitudinal seal 26. As it continues down the production
line, flange 58 is folded once as shown in FIG. 7, folded again as
shown in FIG. 8 to form a longitudinal fold line 59 and flattened
or pressed onto side 54 of rear panel 30, as shown in FIG. 9. Thus,
longitudinal margin 26 is sealed and folded flat with the rear
panel of the package to provide a five-layer thickness of material
to add strength to the package as well as improving the integrity
of the seal.
After longitudinal margin 26 is double folded, the strip 48 is
sealed by applying heat and pressure in the spaces 60 between
patties to activate the heat sealable layer 42. The strip 48 then
is stamp cut to provide a top portion 62 of a first package and a
bottom portion 64 of a second package adjacent the first package.
Each package 20 is severed with a sealed top portion 62 which is
longer, for example, approximately three times longer than the
sealed bottom portion 64 and a longitudinal margin 26 running the
length thereof. If desired, cutouts 63 and 65 can be stamp cut at
the same time to provide a tear notch 34 after double folding the
top portion 62. Alternatively, the tear notch can be stamp cut
after the package has been completed.
Top margin 22 is then formed, as shown in FIG. 10, by folding
approximately one-third of top portion 62 onto itself, as shown in
FIG. 11, making another equal fold as shown in FIG. 12 to form top
fold line 35, and pressing or flattening the double-fold together
to form top margin 22, as shown in FIG. 14. The cutouts 63 and 65,
if properly positioned will then align themselves to form tear
notch 34.
Tear notch 34 is preferably formed in such position that its apex
is on longitudinal fold line 59 of longitudinal margin 26. Hole 32
may be punched or cut through top margin 22 directly below tear
notch 34 in alignment with longitudinal fold line 59. If desired,
hole 32 may be formed by stamp cutting during the severing step
three holes in the top portion 62 which become aligned after
folding to form hole 32.
The dimensions of package 20 should be less than those of the
heating compartment of a conventional household toaster. However,
the dimensions of package 20 are determined by the particular
heating appliance in which it is designed to be heated; and,
consequently, it is clear that packages according to the present
invention may be designed for larger and different heating
appliances in order to accommodate larger portions of food or to
provide quicker heating.
The use of package 20 for heating or cooking and serving will be
described with reference to FIGS. 14, 15 and 16.
Package 20 is retrieved from its storage space, wherein it may be
stocked on a shelf or supported on a hook or rod through hole 32 in
a freezer or closet, by grasping top margin 22 as a handle to
prevent unintentional tearing or other damage to the package. Top
margin 22 is grasped by the server with both hands, and force is
applied to longitudinal margin 26 at tear notch 34 with one hand
while holding top margin 22 steady with the other hand to tear
package 20 just far enough downwardly to permit communication of
the interior of the package with the atmosphere. The tear line 66
starting from tear notch 34 for forming the vent, is directed down
longitudinal fold line 59 of longitudinal seal 26 and tearing is
facilitated due to the weakening or fatigue of the metallic foil
caused by the bend made in forming the fold. However, tearing is
stopped as soon as venting has been established. In order to assure
proper venting a mark may be printed on rear panel 30 to indicate
the proper termination of the vent tear line.
Venting of package 20 separates top seal 22 into two portions 68
and 70. Portion 70 may now be unfolded, as shown in FIG. 15, to
form a handling tab 72 which facilitates insertion of the package
20 into and removal from a toaster. Thus, by combining handling tab
72 with package 20 the package may be compactly formed to require
only a minimum of space for storage while retaining a gripping edge
or handling tab which extends out of the toaster and remains
sufficiently cool to facilitate easy access to the package.
Package 20 is protected from damage caused by the heating elements
inside the toaster due to its simplicity of design and smooth
surfaces which permit no loose edges or flaps that could be
accidentally snagged in the toaster. By keeping bottom margin 24
relatively short, package 20 has a good base of support at the
bottom of the toaster which support is enhanced by longitudinal
margin 26. Conventional toasters are ideal for use with the package
of the present invention since they provide good heat and have
timing devices constructed integrally therewith. Once package 20 is
inserted in the toaster, the toaster is energized under the control
of the timing device, and whether the food contained in package 20
is to be actually cooked or merely heated depends on the type of
food and its desired preparation. Vent 66 permits steam and vapors
to escape to the atmosphere and the size of the vent may vary with
desired cooking conditions.
Once the contents have been sufficiently heated or cooked, package
20 may be removed from toaster 73 with the aid of handling tab 72
which extends out of toaster 73 and remains cool. In order to serve
the food the top end of longitudinal margin 26 which also was out
of the toaster and remained cool is grasped and pulled from the top
to the bottom of the package. Thus, margin 26 is used as a tear
strip 74, and as previously mentioned margin 26 is easily torn
along longitudinal fold line 59 due to the weakening of the
metallic foil by the bend of the fold. Tear line 66 is now extended
through the entire length of the package to fully open the package
and permit easy removal of the food for serving or to permit the
food to be eaten directly from the package.
The characteristics of material 48, as structurally described with
respect to FIG. 4, are excellent for cooking or heating since inner
layer 42 is heat reflective to evenly distribute heat and since
outer layer 36 may be printed in a solid dark color to control heat
absorption and distribution.
The disadvantages heretofore present with the use of similar
materials are obviated by the construction of the package of the
present invention. That is, the great propensity of metallic foil
to tear during handling is greatly reduced or eliminated by the
double-folded top margin 22 and the double-folded longitudinal
margin 26 yet is advantageously utilized for venting and opening
the package. Double-fold top margin 22 has a multilayer thickness
of material 48, thus, top margin 22 is tear resistant yet easily
vented due to tear notch 34.
The precise alignment of tear notch 34 on longitudinal fold line 59
of longitudinal seal 26 permits advantageous cooperation between
top margin 22 and longitudinal margin 26. That is, when top margin
22 is grasped at longitudinal margin 26 for initial venting,
longitudinal margin 26 presents as much as 18 layers of material to
thereby assure the tearing of a precise vent and tear line.
Furthermore, top margin 22 and longitudinal margin 26 form a
T-shaped support structure for the package due to their multilayer
configurations whereby the material is strengthened in transverse
and longitudinal directions to retain its initial shape and to
resist tearing and mutilation.
By disposing hole 32 directly under tear notch 34 in alignment with
longitudinal fold line 59, top margin 22 is not weakened at a point
which could cause inadvertent tearing or imprecise venting and yet
the multilayer thickness of top margin 22 with the support of
longitudinal margin 26 permits hole 32 to be used for hook or rod
storage without danger of damage to the package.
Longitudinal margin 26 need not be centered on rear panel 30 of the
package and may be located anywhere on rear panel 30 or on either
of the sides of the package.
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