Method and Means for Enhancing Microwave Popping of Popcorn

1. Field of the Invention

The present invention relates to popping of popcorn using microwave energy.

2. Prior Art

A popcorn package for microwave popping is shown in U.S. Pat. No. 3,973,045, issued on Aug. 3, 1976. With minor differences, this publication reflects a type of popcorn package that the assignee of such patent has been marketing in the USA for the last several years. Normally, the popcorn package is kept frozen until ready to use. Also, it is normal for many unpopped kernels to remain in a correctly popped package.

It is therefore an object of the present invention to enhance the popping of a popcorn package provided for microwave popping.

According to the present invention, a layer of metallized ink is printed on the bag of a popcorn package, and in doing so, enhances the subsequent popping of popcorn in the package by microwave energy.

Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheet of drawings in which a preferred structural embodiment incorporating the princples of the present invention is shown by way illustrative example.

FIG. 1 is a front-end elevational view of a popcorn package provided in accordance with the principles of the present invention;

FIG. 2 shows in perspective, the package of FIG. 1, partially opened for popping and partially broken away for illustration;

FIG. 3 is an enlarged vertical cross-section taken generally along line III--III of FIG. 1; and

FIG. 4 is a plan view of a web, partially broken away, from which the bag of FIGS. 1-3 is made.

The principles of the present invention are particularly useful when embodied in a popcorn package as shown in FIGS. 1-3, generally indicated by the numeral 10. The package 10 includes a bag 11 which is sealed closed in an air-tight manner, there being a charge 12 of popcorn, shortening, and optionally salt, enclosed therein.

The bag 11 is manufactured from a web 13 as shown in FIG. 4, there being a severed edge 14 and a prospective severance edge 15 identified by a registration indicator 16 included thereon for being sensed by automatic machinery to provide a cut at the prospective severance line 15, thus, placing all printing (some of which is not shown) on the bag in registration with the severance lines 14.

The web 13 is made up of two plies 17, 18, both of which may be paper, one ply being receptive of printing and the other ply being grease-proof. Alternatively, a grease-proof ply may comprise a polyester such as "Mylar" (trademark).

The web 13 has six prospective longitudinal fold lines 19-24 for forming a pair of gussets 25, 26, (FIG. 3). The web 13 has a transverse prospective fold line 27 about which the end of the bag 11 is folded to provide one sealed end 28 (FIG. 2). Further, the web 13 has a pair of transverse fold lines 29, 30 to provide transverse folds 31, 32 (FIG. 2) about which the sealed end portions of the bag are folded.

The prospective side gusset folding lines 21, 22 represent the outer longitudinal edges of the bag 11, and jointly with the prospective folding lines 29, 30 define an area 33. When the web 13 is folded about the prospective longitudinal folding lines 19-24, the marginal portions of the web overlap one another and are sealed to one another to provide a backseam 34 (FIG. 3). Thus, the area 33 lies at the front side of the bag while the backseam 34 lies at the back of the web.

According to the present invention, during the fabrication of the web 13, there is a layer of metallized ink 35 applied by printing to one of the unexposed sides of one of the web plies 17, 18 so that it is separated by one ply from the atmosphere and by one ply from the contents or charge 12.

The metallized ink layer 35 is made from a commercially available metallic ink having aluminum powder. One example of such ink is Aquaflex Silver No. 4011316 as provided by Sinclair and Balantine, 4100 S. Pulaski, Chicago, Ill. 60632. This ink is modified before printing, by dilution. The diluent may consist entirely of water, and may be a mixture of water and isopropyl alcohol, such diluent mixture being no less than 50% water. The original strength of ink is diluted to contain 15-25% diluent, and thus the ink is diluted to 85-75% of its original strength. The layer of metallized ink 35 is applied to the area 33 so as to overlap its limits. The layer of metallized ink is of such quantity as to have an opacity level of light transmission in the range of 47% to 10% such as measured with a Tobias Densitoneter, model T.C.X.

After the web 13 has been fabricated and printed, the web is folded about its longitudinal prospective fold lines 19-24, the backseam 34 is sealed, and one end 28 is closed and sealed. At this point, marginal portions 35a and 35b of the layer 35 project into the gussets 25, 26, and the bag 11 is now ready to be sold by its manufacturer to a customer whose own indicia such as trademarks and popping instructions have been applied.

The customer now completes the package 10 by inserting the charge 12, sealing the opposite end 36, and applying two folds 31, 32 to complete the package 10 shown in FIG. 1. In that the fold lines 31, 32 made from prospective fold lines 29, 30 extend through the area 35, additional marginal portions 35c, 35d extend beyond such folds or fold lines. When the package of FIG. 1 is unfolded to the position of FIG. 2, the marginal portions 35a-d of the layer 35 extend upwardly from the area 33 at the edges thereof to form a pan-like configuration between the plies 17, 18 so that every portion of the charge 12 is underlaid and encircled by the layer 35 of metallized ink.

The popping instructions and procedures are the same as those now in commercial use. However, the popping results typically in a 40% reduction in unpopped kernels, thereby increasing the yield, and in addition, the kernels on popping experience a greater amount of expansion. Therefore, a higher percentage of the kernels are popped and each pops to a larger size. Thus the use of a layer of metallized ink printed on a bag of a popcorn package enhances the subsequent popping of the popcorn by microwave energy, such enhancement being in the form of both less unpopped kernels and in the form of a larger expansion of a kernel during popping.

Although various minor modifications may be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon, all such embodiments as reasonably and properly come within the scope of my contribution to the art.