US2384720A

US2384720A - Chemical heating container

Info

Publication number: US2384720A
Application number: US507348A
Authority: US
Inventors: Gordon M Babcock; Francis B Rethwisch; Vincent E Furnas
Original assignee: Reynolds Metals Co
Current assignee: Reynolds Metals Co
Priority date: 1943-10-22
Filing date: 1943-10-22
Publication date: 1945-09-11
Anticipated expiration: 1962-09-11

Description

p 1945. M. BABNCOCK ETAL Q 2,384,720

CHEMICAL HEATING CONTAINER Filed Oct. 22, 1943 2 Sheets-Sheet 1 P 1 G; M. BABCOCK EIAL 2,384,720

' CHEMICAL HEATING CONTAINER Filed Oct. 22, 1943 2 Sheets-Sheet 2 llly.

IN ENTOR. MM I I BY "mi 7 W Patented eph 11, 1945 srrss PA 'FFlCE CHEMICAL HEATING WM corporation off Delaware Application October 22, 1943, Serial No. %,348

3 ms. (CH. filth-$63) used structure consistsof a double compartment can, the foodstuffs being in one compartment, usually a central one, and the heating charge in the other. 'Whilesuch a method is entirely operative it is objectionable from the standpoint of bulk and cost and the structure is not readily adapted for re-use.

The object of the present invention is to provide an eilective and inexpensive heating container which may be folded fiat or substantially so, and which may be re-used, being readily transportable without bulk or other than nominal weight. In the use of chemical heating compounds there is generally produced a substantial evolution of gases, and the container is of such character as to readily allow the escape of the gases. In a phase of the present invention means are provided for reducing the surfacetension of the liquid resulting from the addition of water to the reactive chemicals so thatfoaming is controlled and the heating operation may be performed without loss of the heating chemicals or damage to a ration container should the letter be open or looselycovered.

The invention will be described with reference to the accompanying drawings, in which-- Fig. v1 is a view in elevation showing the heating container in condition for use'with a can received therein. v I

Fig. 2 is a sectional e1 vation, the section being through the container ofFig. 1 with the can in position.

Fig. 3 is a composite view showing the end and also the side of the container in collapsed form.

Fig. 4 is a perspective view of the chemical cartridge. r

Fig. 5 is a fragmentary horizontal section on the line 65, Fig. l.

Fig. 6 is a vertical section through the chemical cartridge.

Fig. 7 is a view in elevation, partlyin dotted lines, showing the containertadapted as a sealing envelope for a can and with tear means for exposing the can and chemical cartridge for heating operation.

Fig; 8 is a vertical section through the sealed container on the line 8--8, Fig'. 7.

Fig. 9 is a horizontal section on the line 9-9, Fig. 8, the section being through the container only.

Fig. 10 is a view in elevation showing the position oi the container ears as folded against the walls of the container and over upon the can, for compact shipment. I

Fig. 11 is a view in elevation showing the structure of Fig. 7 with the top of the container torn away and the device ready for use.

Referring to the drawings as shown in Fig. 3, our preferred form of container, for use as a unit of the invention, consists ofa composite sheet folded upon itself and sealed at its longitudinal margins, the container being generally indicated at i and its sealed margins at Ix. In Fig. 3, only one layer of the envelope sheet is shown, for convenience of illustration. However the sheet from which the envelope is made will have an inner foil layer I an: as shown in Fig. 5, so that a surface resistant to caustic action and the general reaction of the heating chemicals is provided. The outer layer of the sheet is preferably an asphaltic-impregnated paper such as kraft paper, although it will be understood that the carrier for the metal foil may be any suitable flexible material, including cloth.

It will be seen that the side margins of the envelope are brought together and sealed. These margins may be heat-sealed by the application of any suitable heat sealing material to the foil surface and applying heat and pressure. The envelope has an unbroken wall at its base, and the marginal bonding of its two walls will provide a strong and readily flexible cup-like container when the envelope is expanded to the shape of Fig. 1. Due to the characteristic of the metal foil in retaining the general shape to which it is distended, the envelope will, when brought to the shape of Fig. 1, maintain such open and cup-like shape during the heating operation.

The envelope is readily formed into cup-like shape by inserting a can 2 and pressing the can downwardly to the bottom of the envelope, the sides of the latter moving outwardly and lower portions thereoi being brought under the can, with the formation of side ears 3, Figs. 1 and 2, serving as feet for the better support of the structure.

Within the envelope container will be positioned a cartridge containing the chemical heating compound, the latter being reactive in the presence of water.

The cartridge may consist of a piece of flexible material folded upon itself to enclose the chemical compound 6, the contacting margins of the foil or other material being bonded together in any suitable manner, as by heat sealing. The cartridge is generally indicated at 5.

We have found that dry sodium hydroxide and coarse aluminum granules, which may be dross aluminum, or aluminum foil "rose buds" give the type of reaction we desire. although any type of aluminum might be used, the speed of the reaction varying largely with the type of aluminum particles. We have also discovered that upon the addition of water to form a heating charge, the presence of a material adapted to reduce the surface tension of the liquid will control foaming and greatly reduce its volume.

As an example:

Foil "rose buds" of aluminum oz- /2 Dry sodium hydroxide -grams 5 Aerosol (sulfonated bi-carboxylic acid ester) do A, Water c c 75 The above heating charge is sufilcient to brin a sealed one pint can of water from a temperature of approximately 40 F.- to a temperature of 145- 150 F. in six minutes.

Our heating containers may be made in all required sizes, including very large containers, as for example, for five gallon cans. As the cans to be heated increase in size, the proportions of the The toil internal surface of the container may be lead foil, the latter being resistant to the chemical reaction.

Prior to subjecting the cartridge to the action of water it may be punctured or cut; and it is desirable that the material of the cartridge be waterprooied so as to preserve its contents prior to use.

The cartridge may consist of aluminum foil carried by a flexible material, for example, paper. which is non-reactive with respect to the chemical charge, so that the aluminum foil oi thecartridge can be part of the heat producing charge.

Reference has been made to foil rose buds, which defines small pieces of foil, as for example about one inch square, which have been crumpled up to form a small wad.

What we claim is as follows:

1. A chemical-heating structure for the contents oi cans and the like which consists in a composite sheet folded upon itself and sealed at its longitudinal margins, the container having an inreactive chemical mixture and the water will be Y en above, which example is suitable for cans of one pint capacity or thereabouts.

In Figs. '7 to 9. inclusive, we have shown our container, with its cartridge, the-container completely sealing the article-containing can to be heated. The container is constructed as in ac- .cordance with Fig. 3, but is longer. After the can is placed in the container the top margin of the container is sealed. In or below the top marginal seal a rip cord 3 may be positioned. As an alternative or along with the rip cord the container may be formed with a weakened line as at w so that the top of the container may be torn away to leave a cup-like body surrounding and supporting the cans as shown in Figs. 7 and 11. In preparing the device of Fig. '1 for shipment the top and bottom or the container may closely conform with the top and bottom of the can, as by pressing those areas of the container toward each other. This will form two sets of opposed ears 8 of the character shown in Fig. 1, and these ears may be folded parallel with the adjacent container walls as shown in Fig. 10.

' correspondingly increased over the example givner layer consisting or metallic foil, the fold of the sheet being at its base. the walls of the container being adapted for distension upon the insertion of a round-wall body such as a can and in such manner that the can is engaged by the container at opposite areas thereof, while at other opposite areas the container is spaced therefrom for the emission of gases, and a cartridge within the container, the cartridge enclosing a chemical mixture adapted to produce heat in the presence of water. i g

2. In combination with a can containing contents for heating, a chemical heating structure which consists of a flexible envelope having an internal metallic foil surface. the can being enclosed within the envelope, a cartridge within the envelope, the cartridge enclosing a chemical mixture adapted to. produce heat in the presence of water, sealing means tor the envelope, the envelope having a weakened line for removal of an upper area thereof to expose the top area of the can. i

3. A device constructed in accordance with claim 2 in which the envelope consists of a composite sheet iolded upon itself and sealed at its longitudinal margin and at its top, the fold of the sheet being atits base, the inner face of the sheet consisting of lead foil, the envelope having spaced sets of ears loldable toward the outer wall ing support of the latter. GORDON M. BABCOCK.

FRANCIS B. RETHWISCH. VINCENT E. FURNAS.