US 2319956 A
Description (OCR text may contain errors)
. y 1943- J. a. SNYDER 2,319,956
PACKAGING PROCESS CHEESE AND THE LIKE Filed June 20. 1940 a) cfamasfi'nya ek Patented May 25, 1943- 2,319,956 PACKAGING PROCESS CHEESE AND THE LIKE James E. Snyder, Akron, Ohio, assignor to Wingfoot Corporation, Wilmington, Del., a corporation of Delaware Application June 20, 1940, Serial No. 341,490
This invention relates to packaging and more particularly to the closing of bags and the like made from a heat-sealable film. The heat-sealable film employed is preferably a rubber hydrochloride film, such as that now on the market, although other heat-scalable films may be used such as films of plasticized polyvinyl derivatives, heat-seala-ble cellulosic materials, 'etc. The invention will be described more particularly as related to the packaging of process cheese in rubber hydrochloride film, although the/invention is not limited thereto.
Process cheese is made by heating and emulsifying one or more grades of cheese often with the addition of seasoning, etc., and it is desirable to package the product in a heated, molten condition. The invention is particularly adapted for the packaging of such cheese, although it may likewise be employed for packaging other hot or cold materials and particularly a fluid product. For example, the process may be used in packaging scrapple, corn mush, chili con came, peanut butter, frozen foods, lard, margarine, etc.
According to this invention the molten process cheese or other material to be packaged is run into a bag of rubber hydrochloride film or other heat-scalable film material. The open end of the bag is then folded to the top of the package and not gas. applied to cause contacting portions of the film to coalesce. A gas fiame or blast of hot air or other suitable source of gas-conducted heat, such as radiant heat, etc., is used for heating the film. It is also ordinarily desirable to press the flaps of the bag to the cheese .package to insure the formation of an air-tight seal. When packaging hot materials the bag may then be inverted so that the weight of the hot contents presses the flaps together thu assisting in forming a tight seal. This is advantageous in the packaging of molten process cheese, for example. Even in packaging cold products, inverting the package is desirable since the weight of the contents insures contact at all point of the sealing surfaces.
When the flaps of the bag arefolded to the cheese and the heat is applied, it will be found that the layer of film adjacent the cheese is not readily raised to the temperature at which it will completely coalesce with the layers above it.
This i due to thefact that the cheese conducts the heat away from the film which is in contact with it and prevents it from being heated to the temperature necessary for coalescence, except when extremely high temperatures are employed,
. in which case there is danger of damaging the of the heat-seal.
The box I is made of wood. It is lined with a bag 2 of rubber hydrochloride film. The bag is a of the envelope type which may be made by folding a sheet of film and uniting the two edges adjoining the fold. The bag is fitted into the box I and filled with the molten cheese. The top of the bag is now closed in the following manner. The swinging fingers 3 are pivoted on the rods 4. The arrows indicatethe motion of the fingers. As the fingers swing down into th bag, they extend the ends of the top until the edge 4 of the sides of the top are brought together. Then by manual operation or by mechanical means, the edges 4 are folded fiat onto the top of the bag or package as shown in Fig. 2. As shown in this figure, the folded over portion of the top of the bag rest on another portion of the top of the bag which is in contact with the cheese.
Gas-conducted heat is now applied from above. This causes the overlapping edges 4 to coalesce and a moisture-tight and air-tight seam is formed all the way across the top of the package. A hot blast of air or a gas flame may be used for forming the seam. The heat is brought to the film thru the surrounding atmosphere and without contact with any heated instrument. Although the gas or hot air may contact the portions of the bag adjacent the edges which have been folded over, these portions which are in contact with the cheese are not readily heated to the sealing temperature. It is the over-lapping portions or edges 4 and the ears formed at the ends of the top of the bag on folding which are readily heated and coalesce. When the cars which protrude over the ends of the box are heated to the temperature at which they coalescethey may wilt as rubber hydrochloride film is apt to wilt when heated. However such wilting does not interfere with the formation of an air-tight and moisture-tight package.
Instead of closing the bag with this particular type of seam, the top of the bag may be folded together in other ways and all exposed edges heated to form a tight seam. The seam shown in the drawing is preferred since in order to form such a seam it is not necessary to heat more than two layers of film.
Pressure on the newly formed seam to maintain the heated portions of the film in contact until they cool may be advantageous. Mere patting by the hand of the operator may be beneficial, particularly where molten cheese or other material is packaged which it is desirable to spread out to some extent to more evenly fill the package.
Such a seal has advantages over one made by pressure with a heated instrument, because pressure on the heated film with a heated instrument tends to make the film thinner at the seam and thus weakens the package.
'The outer container is now closed. If the outer container is of wood, the lid is nailed onto the box. If the outer container is cardboard, the flaps are folded down and preferably sealed. The package may then be inverted. The weight of the heated cheese on the overlapping layers of the film at the seam gives added assurance of getting a tight seam. The package preferably remains in the inverted condition until the film and contents have cooled. The duration of the cooling period will 'depend upon the size of the package. the temperature of the contents, etc. For process cheese, which is heated to a temperature in the range of 150 to 190 F. when placed in the package, a cooling period of twelve hours certainly will give a tight seal and a lesser cooling period may be found satisfactory.
This method of packing has many advantages over the other methods of heat-sealing now employed. These include the fact that this method may be, made actually continuous. It eliminates the mechanically moving heat-sealing platens which are employed in many of the processes now currently'used. Any danger of a hot platen cutting through the heated film or sticking to the film is eliminated. The union of the film is not limited to the area which is brought in contact with the heated platens, but all the contacting surfaces may be heated and sealed together. This is accomplished without heating the film through any intervening material, such a paper or the like. The seal ,formed is not only superior to most or all of the seams formed by other methods, but no complicated equipment is required, and the labor cost of making the seal is low.
1. The method of packaging molten process cheese in a rubber hydrochloride film which comprises lining an outer rigid container with a rubber hydrochloride bag of the envelope type, running molten, process cheese into the bag, extending the upper ends of the bag outward to cause the top of the sides of the bag to come into fiat contact with one another, folding the top edges of the sides of the bag to the top of the package without substantially changing the relation of the two sides of the top of the bag with respect to one another, and then applying heat through the surrounding atmosphere from above to unite the upper edges of the bag and form a tight seam while simultaneously heating the adjoining film ning molten, process cheese into the bag, extending the upper ends of the bag outward to cause the top of the sides of the bag to come into fiat contact with one another, folding said contacting portions of the sides of the bag to be fiat on the top of the package, and then applying heat thru the surrounding atmosphere from above to unite the upper edges of the bag and form a tight seam while simultaneously heating the adjoining film which is in contact with the cheese without heating it to the heat-sealing temperature.
3. The method of packaging molten process cheese in a rubber hydrochloride film which comprises lining an outer rigid container with a rubber hydrochloride bag of the envelope type, running molten, process cheese into the bag, extending the upper ends of the bag outward to cause the top of the sides of the bag to come into contact with one another, folding said contacting portions of the sides of the bag to the top of the package without substantially changing the relation of the two sides of the top of the bag with respect to one another, bringing heat through the surrounding atmosphere to the top layer of the folded film without substantially changing its relation to the other folded portions of the film so as to soften the top layer and unite it to the layer of film immediately below it and thereby form a moisturetight and. air-tight seam throughout the length of the top of the bag while simultaneously heating the adjoining film which is in contact with the cheese without heatingit to the heat-sealing temperature.
4. The method of packaging a material in a bag of rubber hydrochloride film which comprises putting the material into the bag. folding the top of the bag onto the filled portion of the bag and by bringing heat through the atmosphere to the folded portion of the bag, uniting overlapping portions of the folded portion of the bag to form an air-tight enclosure for the material while simultaneously heating the adjoining film which is in contact with the material in the bag without heating it to the heat-sealing temperature.
5. The method of forming a package which comprises putting material into a bag made of heat-sealable film, folding the top edges of the bag to the filled portion of the bag in such a way that only two layers of film rest on that portion of the bag which is filled with the material and then conducting heat through the atmosphere to the top layer of the folded film to unite it to the layer immediately thereunder to form a tight seal whilesimultaneouslyheating the adjoining film which is in contact with the material in the bag without heating it to the heat-sealing temperature.
6. The method of filling a bag of heat-scalable film with a fluid which comprises causing the fluid to run into the bag. bringing the upper edges of the bag together and folding them to the filled portion of the bag in such a way that above the filled portion of the bag there are no more than two layers of the film, then applying a flame to the outer layer of the folded film to cause it to unite to the contacting layer to form an air-tight seam throughout the length of the bag, and simultaneously applying the flame to the adjoining film and maintaining contact between said adjoining film and the contents of the bag to conduct heat away from said adjoining film through the contents of the bag to prevent its being raised to the heat-sealing temperature.
7 JAMES E. SNYDER.
CERTIFICATE OF CORRECTION. 3 Patent N032, 519, 956. May. 2 1915.
JAMES E. SNYDER.
It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Rage 1, first I column, line 29, for "not" read --hot--'; page 2, first column, line fijf'for "packing" read "packaging-q and that the said Letters Petent should be read with this correction therein that the same may conform to the record of the case in the Patent Office. v
Signed and sealed this 29th day of June, A. D, 191;}.
V i Henry Van Arsdale, (Seal) Acting Commissioner of Patents.