Paper-wrapped polystyrene foam beverage container

Abstract

A beverage container having a polystyrene foam cup body wrapped in a paper covering is disclosed. The paper-wrapped polystyrene foam beverage container may provide thermal insulation while simultaneously providing a means to display high quality printed matter to the user. A method of making the paper wrapped polystyrene foam cups includes providing a polystyrene foam cup body that has been allowed to shrink to its stable proportions and thereafter applying the paper wrap. A promotional item may be attached to the paper wrap.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The subject matter disclosed and claimed herein is related to the subject matter disclosed in U.S. patent application no. [attorney docket RHC-0009], filed Dec. 17, 2004, entitled “Paper-Wrapped Polymer Beverage Container.” The disclosure of the above-referenced U.S. patent application is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

Generally, the invention relates to beverage containers. More particularly, the invention relates to paper-wrapped, expanded polystyrene beverage containers.

BACKGROUND OF THE INVENTION

Disposable hot-beverage containers, such as coffee cups, for example, are typically made of paperboard or polystyrene foam. Paperboard cups may be desirable for a number of reasons. For example, a paperboard cup may provide a high-quality printable surface from the lip of the cup to its base. Also, paperboard cups tend to be suitable for the attachment of promotional items, such as detachable coupons, labels, stickers, or game pieces, for example, that vendors frequently use for marketing purposes.

Paperboard cups, however, tend to be poor insulators of heat. A paperboard cup containing a hot beverage, therefore, may be difficult to hold. To compensate for the lack of insulation provided by a single paperboard cup, a plurality of such cups may be nested together. A separate cardboard sleeve may be used to provide insulation, or the cup may include handles.

Polystyrene foam cups typically provide better thermal insulation than do paperboard cups. Accordingly, polystyrene foam cups tend to be more suitable than paperboard cups for containing hot beverages—at least in terms of thermal insulation. The exterior surface of a polystyrene foam cup, however, typically does not provide for high-quality printing. Also, polystyrene foam cups are typically not as suitable for the attachment of promotional items as are paperboard cups.

It would be advantageous, therefore, if there were available a disposable beverage container having thermal insulation properties such as provided by polystyrene foam as well as an exterior surface that is suitable for the attachment of promotional items and for high-quality printing from the lip of the cup to its base.

SUMMARY OF THE INVENTION

A beverage container according to the invention may include a polystyrene foam body covered with a paperboard wrapping. The polystyrene foam body may provide thermal insulation and may be useful in containing hot beverages in a manner comfortable to a user. The paperboard wrapping may provide for high quality printing on the entire exterior of the cup. Additionally, the paperboard wrapping may permit the use of attachments such as those a beverage vendor may use as promotional items. Examples of such promotional items include detachable coupons, tear-off labels or stickers, or playing pieces for a game.

A method for producing such a beverage container may include providing a polystyrene foam cup body that has been allowed to shrink to its substantially stable proportions. After polystyrene foam shrinkage has occurred, a paper wrap may be applied to the exterior of the cup body using an adhesive, for example. The paper wrap may be pre-printed, or printing may occur after the paper wrap is applied to the cup body. A promotional item may be affixed to the paper wrap either before or after application of the paper wrap to the cup body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1D depict an example embodiment of a method according to the invention for manufacturing a beverage container.

FIGS. 2A-2E provide several views of an example embodiment of a beverage container according to the invention.

FIG. 3 is a partial cut-away view of an example embodiment of a beverage container according to the invention.

FIG. 4 depicts a typical promotional item attached to an example embodiment of a beverage container according to the invention.

FIG. 5 provides a flow diagram of an example embodiment of a method according to the invention for manufacturing a beverage container.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIGS. 1A-1D depict an example embodiment of a method according to the invention for manufacturing a beverage container. As shown in FIG. 1A, a first end 112 of a paper wrap 120 may be placed on a cup body 105 and held in place. The cup body 105 may be made of polystyrene foam, such as expanded polystyrene (EPS), for example. The paper wrap 120 may be made of paperboard, such as solid bleached sulfate (SBS) paperboard, for example. The SBS paperboard may have a clay coating that provides a smooth finish onto which high quality printing may be presented on the finished cup 100. The paperboard may have a thickness of between about eight and about fourteen mils. The paper wrap may have a smooth surface for the display of printed material. Alternatively, the paper wrap may be scored or ridged to provide additional slip resistance for a user holding a cup, for example, or for decorative or other purposes.

As shown in FIG. 1B, the paper wrap 120 may be wrapped around the cup body 105 such that a second end 114 of the paper wrap 120 is made available for mating with the first end 112. As shown in FIG. 1C, the first end 112 may be mated with the second end 114 to create a seam 116 on the finished container 100. The finished seam 116 shown in FIG. 1C may be finished as either a lap joint edge or a butt-edge joint. An adhesive or crimp may be used to form the seam.

An adhesive may be used to attach the paper wrap 120 to the exterior sidewall of the cup body 105. One or more beads of adhesive may be applied at the edges 112 and 114 of the paper wrap or across the inside surface of the paper wrap 120. As shown in FIG. 1D, one or more lines of adhesive 121 may be placed on the inside face of the paper wrap such that an adhesive overlap joint is constructed when the paper wrap is applied around the cup body. Alternatively or additionally, one or more lines of adhesive 122 and 123 (two exemplary lines are shown) may be placed transversely on the inside face of the paper wrap. A surface coat of adhesive, from a spray of adhesive, for example, may be used. A butt-edge joint may be used where the paper wrap edges 112 and 114 are joined edge-to-edge with little or no overlap. This type of attachment may be realized by applying an adhesive to either the cup body in the area of the resulting edge joint (see 116, FIG. 1C) or by applying an adhesive to the inside face of the paper wrap near the ends of edges 112 and 114.

FIG. 2A depicts an assembled beverage container 100 in an isometric view showing the top of the cup assembly 100. The view depicts an inside surface of the cup body 105b as well as the lip 110 and the paper wrap 120. Although a blank paper wrap is shown, it is to be understood that the paper wrap 120 may contain printed material.

FIG. 2B depicts an isometric view showing the bottom of cup 100. As shown, the paper wrap 120 may extend along the full length of the cup 100, from the lip 110 to the bottom of the cup. It should be understood, however, that the paper wrap need not extend the full length of the cup. For example, the paperboard may be sized to expose a portion of the cup body sidewall just above the bottom of the cup body.

The exterior surface 105a of the bottom wall of the cup body may be recessed a distance 260 to accommodate the protrusion of dimples resulting from manufacturing. The exterior of the bottom wall of the cup body may be covered, in part or entirely, with paper wrap. This may be accomplished via a folding and crimping of the paperboard covering the exterior of the bottom wall of the cup body. Alternately, a bottom paper cover may be realized using a separate disc of paperboard attached to the bottom of the cup.

FIG. 2C depicts a side view of a paper wrapped polystyrene foam cup 100 having a cup height H, a top diameter D1, and bottom diameter D2. Table 1 provides example dimensions. Though the dimensions provided in Table 1 are examples only, it should be understood that such dimensions provide for assembly of the cup 100 via standard manufacturing techniques and for shipping of a plurality of such cups in standard containers. Dispensing of the assembled cups may be accommodated by size standardization.

TABLE 1
Descriptive			Bottom Diameter
Cup Size	Height (H)	Top Diameter (D1)	(D2)
12 Ounce	4.288 inches	3.650 inches	2.100 inches
16 Ounce	5.170 inches	3.650 inches	2.193 inches
20 Ounce	6.061 inches	3.650 inches	2.376 inches

FIGS. 2D and 2E are bottom and top views, respectively, of an example embodiment of a paper-wrapped EPS cup according to the invention. The bottom view of FIG. 2D shows the outside surface 105a of the bottom wall of the cup body and the paper wrap 120. The top view of FIG. 2E shows, from the outside of the drawing,moving inward, the cup lip 110, the inside wall 105b of the cup body, a stacking shelf 108 of the inside cup body wall 105c, a straight section 109 at the bottom of the cup body and the inside surface 105c of the bottom wall of the cup body. The stacking shelf 108 and the straight section at the bottom of the cup appear as concentric rings on FIG. 2E but are more clearly depicted in FIG. 3.

FIG. 3 depicts a cross section of an embodiment of paper wrapped polystyrene foam cup 100, having a lip 110 and a paperboard wrap 120. Details of the cup body include an inner wall 105b, a stacking shelf 108 on the inside cup body wall 105b, a straight section 109 at the bottom of the cup body, the inside surface 105c of the bottom wall of the cup body and the outside surface 105c of the bottom wall. The stacking shelf 108 allows a plurality of such paper-wrapped polystyrene foam cups to be stacked one cup upon another such that a desirable pitch may be achieved between stacked cups.

FIG. 3 depicts a plane P formed by the external side wall of cup body 105. In typical polystyrene foam cup designs, the exterior side wall juts out to provide additional thickness to the cup wall under the lip. As shown in FIG. 3, the external wall under the lip may be straight to maximize contact between the exterior side wall of the cup body 105 and the paper wrap 120. Extra thickness of the lip may be achieved by the addition of wall thickness on the inside wall, at 105d, to provide extra strength and rigidity to the lip 110. The thickness L1 of the lip 110 may be roughly equal to or greater than the height L2 of the lip 110. In an example embodiment, the thickness L1 of lip 110 may be roughly 50% more than the height L2 of the lip. A typical set of dimensions for lip width L1 and lip height L2 are 0.100 and 0.150, respectively.

FIG. 4 depicts an assembled paper-wrapped polystyrene foam beverage container with an attached promotional item 450. The cup 400 of FIG. 4 includes a cup body 405 having a lip 410 and a paper wrap 420. The optional promotional item 450 is attached to the paper wrap 420. The promotional item 450 may be attached to the paper wrap 420 via an adhesive after the cup 400 has been assembled. Alternatively, the promotional item 450 may be attached to the paper wrap 420 before the cup 400 is assembled. An additional alternative is to fabricate the promotional item 450 into the paper wrap 420 so that no separate process for attachment of the promotional item is necessary. For example, the promotional item may be integral to the paper wrap or a second layer of the paper wrap 420.

As shown, the promotional item 450 may have a separable portion 457 which may be removed. The removal of the separable portion 457 may be accommodated by either a tab or a cut-out in allowing a user to pull on the separable item. Perforations 455 in the promotional item layer allow the separable portion to be easily removed. The separable item 457 may be a useful marketing item such as a coupon for merchandise or a game piece. Other methods of displaying and attaching a promotional item 450 to a paper wrap 420 may be accommodated such as are commonly used in making separable labels. Examples include promotional labels similar to those on medicine containers where a topmost layer can be removed to expose information printed on either the topmost layer or a second, non-separable, layer.

FIG. 5 is a depiction of a process 500 of making a paper wrapped polystyrene foam cup assembly. The process begins by providing a polystyrene foam cup body (step 502). In one embodiment the cup body is an expanded polystyrene cup body. The cup body may have an integral cup lip. The polystyrene foam cup body may be allowed to cure or shrink (step 506) before being used in the cup assembly. Since shrinkage may occur in polystyrene foam materials as the material cures after manufacture, the invention accommodates the effect by preferably using cup bodies that have been reduced to their substantially stable proportions before application of a paper wrap on the body.

In an ambient environment, shrinkage will occur in roughly a week. However, as local ambient environments are subject to pressure, temperature, and humidity variations, the one week time period may have a tolerance of about two days. In a controlled environment, where temperature, pressure, and or humidity are regulated, the shrinkage time may be altered to shorten the average one week period for shrinkage. It has been discovered that, if the paperboard is applied before the cup is allowed to shrink to its stable proportions, the paperboard wrinkles as the polystyrene foam body shrinks. Allowing the cup body to shrink before application of the paperboard prevents wrinkling of the paperboard.

A paper wrap is preferably provided (step 508) before the assembly of the cup. The paper wrap may be made of clay-coated SBS paperboard, which provides for high-quality printing on the paper wrap. The paper wrap may be pre-printed, or printing may occur after the wrap is applied to the cup body.

The paper wrap may then be applied (step 510) to the polystyrene foam cup body. An adhesive may be placed on the paper wrap, the cup body, or both. The paper wrap may be attached to the cup body via a technique that includes overlapping the paper wrap ends, and then crimping or butt-joining the paper wrap ends.

After the paper wrap is affixed to the cup body, the cup assembly may be allowed to cure if an adhesive is used. A promotional item may be attached to the paper wrap (step 512). The promotional item may be affixed to the exterior of the paper wrap using any commonly known technique such as an adhesive or a crimp. The optional step of promotional item attachment may be skipped if no promotional item is desired or if the promotional item is pre-affixed to the paper wrap before the paper wrap is attached in step 510.

Though aspects of the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications and additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the claimed invention should not be limited to any single embodiment, but rather should be construed in breadth and scope in accordance with the appended claims.

Claims

1. A beverage container, comprising:

a polystyrene foam cup body having a bottom and a side wall extending from the bottom, the side wall forming an open end opposite the bottom; and

a paper wrap disposed circumferentially around an exterior of the cup body.

2. The beverage container of claim 1, wherein the side wall has a length and the paper wrap extends the length of the side wall.

3. The beverage container of claim 1, wherein the cup body comprises a lip disposed on the open end thereof.

4. The beverage container of claim 3, wherein the paper wrap extends from an underside of the lip toward the bottom of the cup body.

5. The beverage container of claim 4, wherein the paper wrap extends to the bottom of the cup body.

6. The beverage container of claim 5, wherein the paper wrap has an external surface that is suitable for displaying printed material.

7. The beverage container of claim 1, wherein the paper wrap has a smooth external surface.

8. The beverage container of claim 1, wherein the paper wrap comprises a solid bleached sulfate (SBS) paper.

9. The beverage container of claim 8, wherein the SBS paper is clay coated.

10. The beverage container of claim 9, wherein the SBS paper has a thickness of between about eight and about fourteen mils.

11. The beverage container of claim 1, further comprising a promotional item affixed to an exterior surface of the paper wrap.

12. The beverage container of claim 11, wherein the promotional item is removable from the paper wrap.

13. The beverage container of claim 1, wherein the paper wrap is affixed to the exterior of the cup body via an adhesive.

14. The beverage container of claim 13, wherein edges of the paper wrap are at least one of adhesively overlapped and adhesively edge joined.

15. The beverage container of claim 13, wherein the adhesive is applied to an inside face of the paper wrap.

16. The beverage container of claim 1, wherein edges of the paper wrap are crimped together.

17. The beverage container of claim 1, wherein the polystyrene foam is expanded polystyrene.

18. The beverage container of claim 1, wherein the side wall has an inner surface that is perpendicular to the cup bottom.

19. The beverage container of claim 1, wherein cup body is substantially stabilized in size before the paper wrap is disposed around the exterior of the cup body.

20. A beverage container, comprising:

an expanded polystyrene cup body having a bottom, a straight side wall extending from the bottom, the side wall forming an open end, and a lip disposed on the open end; and

a paper wrap disposed around an exterior surface of the side wall, the paper wrap extending from an underside of the lip to the bottom of the cup body and having an external surface that is suitable for displaying printed material.

21. The beverage container of claim 20, wherein the paper wrap comprises a clay-coated, solid bleached sulfate (SBS) paper.

22. The beverage container of claim 20, further comprising a promotional item affixed to an exterior surface of the paper wrap.

23. A method of manufacturing a beverage container, the method comprising:

providing a polystyrene foam cup body having a bottom and a side wall that extends from the bottom;

allowing the cup body to shrink to a substantially stable size; and

affixing a paper wrap around the cup body.

24. The method of claim 23, wherein allowing the cup body to shrink comprises allowing the cup body to shrink while exposed to at least one of an ambient environment and a controlled environment.

25. The method of claim 24, wherein the controlled environment comprises at least one of a pressure controlled environment and temperature controlled environment.

26. The method of claim 23, wherein allowing the cup body to shrink comprises allowing the cup body to shrink for about five to nine days.

27. The method of claim 23, wherein affixing the paper wrap around the cup body comprises extending the paper wrap along a length of the side wall.

28. The method of claim 23, wherein affixing the paper wrap around the cup body comprises affixing the paper wrap around the cup body via an adhesive.

29. The method of claim 28, wherein the adhesive is applied to the paper wrap such that edges of the paper wrap become at least one of adhesively overlapped and adhesively edge joined.

30. The method of claim 28, wherein the adhesive is applied to an inside face of the paper wrap.

31. The method of claim 23, wherein affixing the paper wrap around the cup body comprises affixing the paper wrap by crimping edges of the paper wrap together.

32. The method of claim 23, wherein the paper wrap comprises a solid bleached sulfate (SBS) paper.

33. The method of claim 23, wherein affixing a paper wrap around body portion comprises affixing a paper wrap having at least one detachable promotional item.

34. The method of claim 23, further comprising affixing a detachable promotional item to the paper wrap.