1. Field of Invention
The present invention relates generally to cartons for ice cream and the like, and more particularly to structures for effectively sealing the ends of such cartons.
2. Background Art
Conventional ice cream cartons generally consist of front, bottom, back, top and cover panels hingedly connected to each other. When forming the carton from a carton blank, the front panel and cover panel are glued to each other to form a rectangular tube. Each of the panels has a right and a left end flap associated therewith which are folded one at a time so as to be generally perpendicular with the panels in order to close each end of the rectangular tube. Because these cartons often contain liquid or semi-frozen liquid such as ice cream, it is important to form a good seal around the edges of the end flaps where those edges contact the panels. Absent a good seal, the contents of the carton may leak causing an undesirable appearance and possibly damaging other goods.
It is also important to have a good seal between the upper edge of the front panel and the line of juncture or hinge between the top panel and cover panel of the carton. Previously, applicant has formed such a seal by providing a line of weakness in the front panel adjacent the edge of that panel which contacts the line of juncture between the top panel and the cover panel. This line of weakness permits the front panel to bow slightly when the liquid material placed in the carton freezes and expands. The bowing of the panel permits the top edge of that front panel to remain at the line of juncture, thereby exhibiting a better seal. Absent the line of weakness, the expanding material in the carton might put pressure on the front panel and interfere with the seal between the top of that panel and the line of juncture.
A line of weakness has not heretofore been used on end flaps to create a better seal between those end flaps and the panels or their hinges. When the five end flaps on each side of the carton are folded onto each other and adhered, there may be as many as three or even four end flaps layered over each other at any one position. The numerous layers of end flaps provide a great deal of stiffness in those locations. Thus, it has not been desirable to place a line of weakness on any of the end flaps, since there would be one or more other end flaps present to prevent bowing at that line of weakness.