Disposable cups are routinely used in fast food and take-out restaurants to contain hot drinks. Such cups are of standardized sizes, normally frusto-conical in shape and having an upwardly open top rim adapted to receive one of several standard sizes of plastic lid. These cups are also generally made from wax-covered paper, paperboard or and polystyrene. While polystyrene is an excellent thermal insulator, it is not easily recyclable or biodegradable and thus has fallen out of favor. On the other hand, paper and paperboard are easily recyclable and biodegradable but are poor thermal insulators. As a result, because cups made from paper and paperboard materials have relatively thin walls, when they are filled with a hot beverage, such as coffee, tea or soup, they are difficult to handle comfortably due to the elevated temperature of the contents of the paper cup.
As a result, many dispensers of such hot drinks “double-cup” the beverage, i.e., use two nested cups instead of a single cup. Double cupping is, of course, very wasteful and increases the burden on the environment.
In an effort to provide adequate insulation for comfortable handling of a paper cup, the art has proposed many versions of an insulating sleeve for holding the cup. These sleeves are frequently made from a paperboard blank that is configured to closely embrace the paper cup and protect the user's fingers from high temperatures. These sleeves, being disposable like the cup itself, still represent a much smaller burden on the environment than does an extra cup.
One such insulating sleeve, disclosed in U.S. Pat. No. 5,425,497 to Sorensen, is made from an arcuate blank or band with oppositely extending slots at the ends, the band being of a sheet material characterized by a plurality of discrete, spaced-apart, approximately hemispherically-shaped depressions covering substantially the entire surface of the band, thus creating a plurality of insulating air gaps between the band and a cup around which the band is placed. Another such sleeve, disclosed in U.S. Pat. No. 5,842,633 to Nurse, is an arcuate band of flexible corrugated material with curved side walls, oppositely extending slots adjacent the ends of the band and tabs lying alongside the slots, the tabs projecting only part-way across the width of the band, to facilitate the setting up of the sleeve.
These configurations suffer from several drawbacks. In order to be used for holding a cup, the flat arcuate band must be rolled into a circle and its notched ends must be interlocked to form a tapered sleeve for holding the cup. This type of cup holder sleeve has the disadvantage that it must be assembled on site by the food service worker or the customer, which can be inconvenient and take additional time during food service. In addition, the need to interlock the notched ends on-site risks possible breakage or improper assembly. Other types of sleeves that also require on-site assembly of opposing ends, such as with a fastener, e.g., a pressure-sensitive strip, have similar disadvantages.
Other configurations have been devised that require no on-site assembly other than changing the configuration of the sleeve from a folded, stored position to an open position. For example, in U.S. Pat. No. 5,454,484 to Chelossi, the insulating sleeve is made from a folded arcuate paper stock blank whose ends have been adhered or glued to each other. This folded sleeve, which expands to an oval or eye like shape by squeezing the folded sleeve at the folds, thereby providing an opening to receive the bottom end of a tapered beverage cup, has become the standard in the field.
These conventional insulating cup holders typically are formed from a paperboard blank, as shown in FIG. 1, having arcuate top and bottom edges. When the ends of the blank have been adhered together, the blank may be folded for storage and shipping, as shown in FIGS. 2 and 3. When the blank is formed into an assembled configuration, the holder forms a tapered sleeve that may be positioned about a tapered container. However, manufacturing of these cup holders is very inefficient. Because of the arcuate top and bottom edges, a large portion of a sheet of material from which the insulating holder blanks are cut remains unused. In addition, the arcuate top and bottom edges lead to nonuniform spacing of the container holder blanks within the sheet of material such that advertising material printed on a sleeve is not predictably centered thereon.
It is therefore desirable to provide an insulating cup sleeve that is pre-assembled to allow its immediate use without taking up any time on site, is made not from an arcuate blank and can be stored flat without any complicated handling.
It is further desirable to provide an insulating cup sleeve that facilitates efficient use of materials and efficient use of storage and shipping space.