Disposable cup assembly system and method

A disposable paper cup for serving cold food products and beverages is converted into a hot cup by the addition of an insulating sleeve assembled on the cold cup by the user. One part of a cohesive compound carried by the cold cup cooperates in registry with another part of the cohesive compound carried by the insulating sleeve to instantaneously and aggressively adhere the sleeve in assembly with the cold cup when the sleeve is mounted on the cold cup by the user.

BACKGROUND OF THE INVENTION 
This invention relates in general to disposable containers and deals more 
particularly with an improved means for providing disposable insulated 
containers or hot cups for use in serving hot foods and beverages. 
A cup particularly designed for containing a cold beverage is generally not 
well suited for serving a hot beverage such as coffee. This is 
particularly true of cups of larger size, since there is a tendency to 
more firmly grasp a large cup, which increases the rate of heat transfer 
from the cup to the hand and may result in considerable discomfort. 
Heretofore, various dual purpose disposable containers and cups have been 
provided which are suitable for serving either hot or cold foods or 
beverages. However, such containers and cups generally include some form 
of insulation and are usually more expensive than those required for cold 
food or beverage service. Further, such dual purpose cups are often made 
from environmentally unfriendly plastic materials which are not readily 
biodegradably or recyclable and which present difficult disposal problems. 
Consequently, many restaurants and fast food establishments prefer to stock 
two types of containers, one for cold food and beverage service and 
another for serving hot foods and beverages. Such practice generally 
results in improved customer satisfaction. However, a relatively large 
inventory of disposable containers is required which results in increased 
cost. A further problem may be encountered by the small food establishment 
having limited storage space for maintaining cup inventory. The present 
invention is concerned with these problems. 
It is the general aim of the present invention to provide an improved 
disposable cup assembly system which reduces the cost of providing 
insulated hot cups and enables reduction in the users required cup 
inventory. 
SUMMARY OF THE INVENTION 
In accordance with the invention, a disposable cup assembly comprises a 
basic cold cup made from sheet material and having a frustoconical 
sidewall, a radially disposed bottom wall and a radially disposed annular 
rim at the upper end of the sidewall which defines a circular opening at 
the upper end of the cup. A frustoconical insulating sleeve made from 
sheet material comprises a means for converting the cold cup into a hot 
cup for containing hot liquid and receives the cold cup in an assembled 
condition therein. Spacing means associated with the sleeve may be 
provided for engaging the sidewall in assembled condition to retain 
portions of the sleeve in outwardly spaced insulating relation to 
associated portions of the sidewall. The assembly further includes a 
cohesive material which has a first part disposed on a portion of the 
outer surface of the sidewall and a second part disposed on a portion of 
the inner surface of the sleeve for registry with the first part when the 
sleeve and cold cup are in assembled condition. The first and second 
cohesive parts instantaneously cooperate in adhering engagement with each 
other when the cold cup and the insulating sleeve are moved in assembled 
condition and secure the insulating sleeve and the cold cup in the 
assembled condition.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS AND METHODS 
Turning now to the drawings an insulated hot cup embodying the present 
invention and assembled in accordance with the invention is shown in FIG. 
1 and indicated generally by the reference numeral 10. The illustrated hot 
cup assembly 10 is particularly adapted for containing and serving a hot 
beverage or food product and essentially comprises a basic cold cup, shown 
in FIGS. 2-4 and indicated generally by the reference numeral 12, and an 
insulating sleeve, illustrated in FIG. 5 and designated generally by the 
numeral 14. The cold cup 12 and the insulating sleeve 14 are secured in 
assembly by a two part cohesive material hereinafter designated generally 
by the letter C which includes a first part indicated by the letter A and 
carried by the cold cup 12 and a second part designated by the letter B 
and carried by the insulating sleeve 14. 
In accordance with the invention basic cold cups 12, 12 and insulating 
sleeves 14, 14 are supplied by the cup manufacturer to the user as 
separate elements. The cold cups 12, 12 may be used in the usual manner to 
serve cold beverages and food products. However, when a hot cup is 
required for serving a hot beverage such as coffee or a food product such 
as hot soup, the user may convert a cold cup 12 into an insulated hot cup 
10 by adding an insulating sleeve 14 to the cold cup 12. When the sleeve 
and the cold cup are brought together in assembly the sleeve 
instantaneously adheres to the sidewall of the cold cup to form an 
insulated hot cup assembly, all of which will be hereinafter further 
discussed. 
The basic cold cup 12 comprises a conventional disposable cup of a well 
known type and may be made from any suitable sheet material, but 
preferably, it is formed from a biodegradable material, such as paper, 
using conventional cup forming machinery. Referring particularly to FIG. 
3, the basic cup has a substantially smooth axially elongate frustoconical 
sidewall 16 formed by adhesively joining opposite marginal end portions of 
a sheet material blank (not shown) in overlapping face-to-face relation to 
each other to form a seam 18 which extends longitudinally of the sidewall. 
The upper end portion of the sidewall 16 is rolled or curled outwardly and 
downwardly forming an annular bead or rim 20 at the upper end of the 
sidewall 16 and defining a circular opening at the upper end of the cup 
10. 
A circular bottom wall, indicated at 22 and formed from another sheet 
material blank, preferably paper, includes a depending annular skirt 24. 
The skirt is attached in face-to-face relation to the inner surface of the 
sidewall 16 by a suitable adhesive compound (not shown). The lower 
marginal portion of the sidewall, indicated by the numeral 25, is rolled 
inwardly and upwardly into face-to-face relation with the annular inner 
surface of the skirt 24 and joined to the skirt by a suitable adhesive 
compound (not shown) to connect the bottom wall 22 in substantially liquid 
tight engagement to the frustoconical sidewall 16, as best shown in FIG. 
3. 
The sleeve 14, shown in FIG. 4, is formed from a sleeve blank cut from 
sheet material, preferably paper. A typical sleeve blank, shown in FIG. 6 
and indicated generally at 26, is preferably formed by a cutting or 
blanking machine operation. The resulting formed blank 26 has arcuate 
upper and lower edges indicated at 28 and 30, respectively, which have a 
common center of curvature but differing radii of curvature. The sleeve 
blank 26 is further defined by opposite side marginal portions 32 and 34 
and may be sized to cover the entire exposed outer surface of the sidewall 
or only a portion of the exposed sidewall surface, as shown in FIG. 1. 
The insulating sleeve 14 is further prepared by forming or scoring a 
plurality of spaced apart and generally radially extending shallow 
indentations 36, 36 in the outer surface of the blank 26 to produce 
corresponding radially extending ribs 38, 38 which project inwardly from 
the opposite or inner surface of the blank 26. The ribs 38, 38 are 
preferably equiangularly spaced apart and may terminate in spaced relation 
to the upper and lower marginal edges 28 and 30 or may extend across the 
entire blank 26 between the latter marginal edges substantially as shown 
in the drawings. The blank cutting and the rib forming operations are 
preferably simultaneously performed using a blanking and forming press. 
The frustoconical insulating sleeve 14 formed from the sleeve blank 26 is 
used to convert the basic cold cup, the cup 12, shown in FIGS. 2-4 into an 
insulated hot cup 10, shown in FIG. 1 and suitable for dispensing hot 
drinks or other hot food products. In order to assure that the insulating 
hot cup possess the required structurally integrity to withstand normal 
handling and resist separation of the sleeve from the cup the sleeve 14 is 
adhered to the cup 12, and it is for this reason that the cohesive 
material C is employed. 
Cohesive materials are well known in the adhesive art and have been used 
extensively in the production of other products such as selfsealing 
envelopes, for example, and various cohesive materials are presently 
available which are suitable for use in practicing the present invention. 
An ideal cohesive material for use in practicing the invention is one 
which comprises two parts or substances, neither of which is particularly 
tacky per se. Each of two substances is applied to a separate carrier. 
When the two substances are brought into contact with each other at least 
one of the substances becomes instantaneously tacky and forms an effective 
adhesive layer which immediately adhesively joins the two carriers in 
assembly. 
The cohesive compound used must be formulated so that the two parts of the 
compound remain stable and resist deterioration at ambient temperature 
while providing effective cohesion in the temperatures range normally 
encountered in use. 
One cohesive system employs an adhesive precursor layer which is applied to 
an associated carrier and a tackifier layer which is applied to the 
another carrier. The aforesaid product may be formulated to provide an 
instantaneous aggressive tack to secure the two carriers in substantially 
permanent assembly with each other when the two cohesive layers are 
brought together in substantial face-to-face engagement with each other. 
Cohesive materials of the type generally aforedescribed are discussed in 
U.S. Pat. No. 4,391,853, to Pointon, issued Jul. 5, 1983, and hereby 
adopted by reference as part of the present disclosure. 
Further considering the insulated cup assembly 10, one of the components A, 
B which comprise the cohesive compound C is carried by the cold cup 12 
whereas the other of the components A, B is carried by the insulating 
sleeve 14. At least one of the components A, B comprises a coaxial annular 
layer or band whereas the other of the components may comprise a single 
patch of cohesive material or a plurality of angularly spaced apart 
patches of material for registry with the annular band when the cup 12 and 
sleeve 14 are brought together in assembled condition. 
In accordance with the presently preferred method for practicing the 
invention the part A comprises an adhesive precursor layer or annular band 
applied to the outer surface of the cold cup 12 in downwardly spaced 
relation to the cup rim 20 so that a user's lips will not touch the band A 
during normal cup usage. Preferably, and as shown, the distance between 
the upper surface of the cup rim and the lower edge of the annular band A, 
measured in an axial direction, is less than the axial distance between 
the lower edge of the cup and the upper surface of the bottom wall. This 
dimensional relationship assures that when a plurality of cold cups are 
stored in nested relation to each other, as shown in FIG. 4, the adhesive 
precursor layer A on the nested cup will not enter the cup therebelow to 
contaminate the rim or inner surface of the cup. 
The other cohesive component or tackifier layer B is applied to the inner 
surface of the sleeve 14. The tackifier layer B may comprise a single 
patch of material, but preferably, and as shown, it also comprises an 
annular band. The two annular bands of material A and B are disposed on 
the cup and on the sleeve for registry with each other when the sleeve is 
assembled on the cup. The inner surfaces of the frustoconical sleeve 14, 
defined by the ribs 38, 38 are arranged for complementary engagement with 
the outer surface of the cup sidewall when the sleeve is in assembled 
condition with the cup. 
As shown, one of the cohesive bands is preferably somewhat wider than the 
other so that when the sleeve 14 is brought into assembled engagement with 
the cup 12 proper registration between the cohesive bands will be 
substantially assured. Since the inner surfaces of the sleeve, defined by 
the ribs 38, 38, substantially complement the outer surface of the 
sidewall 16 some degree of "taper lock" will occur when the sleeve is 
seated on the cup sidewall. This arrangement assures that the tackifier 
layer will be brought into activating engagement with the adhesive 
precursor layer as a result of the pressure normally applied to bring the 
two parts into assembly. Thus, the sleeve 14 will be instantaneously and 
permanently adhered to the cup 12 during assembly. 
The present concept of supplying separate cold cups and insulating sleeves 
for permanent assembly by the user at the time of use enables a 
substantial reduction in the cost of producing hot cups enabling the 
producer to make such cups available to the user at reduced cost. 
In accordance with a further concept of the invention insulated sleeves may 
be supplied to the user as flat sleeve blanks to be formed into sleeves 
and assembled by the user, as required. When sleeves are provided in flat 
blank form each sleeve carries a quantity of a cohesive compound B on the 
inner surface thereof for registry with a cohesive compound A carried by 
an associated cold cup. In addition, a strip of one of the compounds A, B 
is applied to the inner side of the blank at the marginal portion 32, as 
indicated at A' and another strip of the compound B is applied to the 
outer side of the blank at the marginal portion 34 as indicated at B', 
thereby enabling the sleeve blank to be wrapped about an associated cold 
cup 12 and joined by bringing the cohesive strips or layers A' and B' into 
engagement to form a seam such as the seam 18. 
Supplying the sleeve blanks to the ultimate user in fiat form substantially 
reduces the space required to maintain an inventory of hot cups. This 
space saving feature is particularly important to the operator of a small 
restaurant or fast food establishment having limited storage space.