Milk carton blank and milk carton with pour spout

A milk carton blank formable into a liquid tight parallelepiped shaped milk carton. The milk carton blank comprises a generally rectangular shape having a plurality of panel portions formed by a gridwork of longitudinal and transverse fold lines. Cutout portions in oppositely positioned top and bottom panel portions allow the top and bottom panel portions to be folded and sealed with a relatively small number of operations. A perforated tab portion is described which may be removed from a tongue portion of the milk carton to provide a pouring spout. Additional folding lines are described which allow a portion of a top and lateral side panel of the milk carton to be thrust outwardly to facilitate pouring of liquid therefrom.

BACKGROUND OF THE INVENTION 
The present invention relates to milk carton blanks and, more particularly, 
to a milk carton blank formed from a sheet of laminated composite material 
having a central layer of paperboard material and having a single layer of 
plastic material adhesively secured to each surface of the paper material 
which is formable into a liquid tight carton having a right regular 
parallelepiped shape which may be provided with a pouring spout formed 
entirely from the unitary milk carton blank. 
Over the past several decades, a number of containers have been designed 
for use in storing consumable liquids such as milk and the like. 
Stetler, U.S. Pat. No. 3,985,287 discloses a one-piece blank which is 
formable into a carton having a rectangular cross-section. The carton is 
adapted for use as a half gallon milk carton and the sheet material used 
for the carton blank is 24 point paperboard coated with polyethylene on 
both sides. The sealing of the carton is effected by pressing adjacent 
portions together and applying heat to melt the polyethylene. 
The blank is provided with a plurality of crease/fold lines which allow it 
to be folded into a rectangular box-like configuration. Crease lines form 
four side panels. Two side panels of lesser width each are provided with 
"half flaps" at their ends. When the carton is folded, each half flap 
extends slightly more than half way across the end of the carton, 
overlapping enough to enable formation of a seal. A plurality of the 
blanks can be internested for cutting from a single sheet of material. For 
this purpose, the width of each of the greater width side panels is made 
equal to the sum of the width of one of the lesser width side panels plus 
twice the combined width of the pair of sealing flaps at the sides of one 
of the end panels. 
Steinke et al, U.S. Pat. No. 4,308,956, discloses a resealable container 
which may have a square or rectangular three-dimensional configuration 
formed from a generally rectangular carton blank. The carton blank may be 
constructed from cardboard, pasteboard, kraft, newsback board, solid 
bleached sulfate, or certain polymeric materials capable of being scored, 
folded, and die-cut, such as polyethylene. 
The blank from which the carton is cut is subdivided into a plurality of 
rectangular panel portion. The top panel portions having specially adapted 
cutout portions therein which, when folded together, create a resealable 
flap. A hinge flap portion is adapted to open and close the container with 
a diecut portion secured to the hinge flap. The carton is especially 
adapted for dispensing particulate or powdered material. 
Carlsson, U.S. Pat. No. 4,113,103, discloses an opening arrangement for 
packing containers and shows a packing container having a parallelepiped 
(rectangular box) shape which is made of a laminated carton forming 
material comprising a carrier layer of paper provided on both sides with 
layers of plastic material which are impervious to liquid. 
The opening arrangement is positioned partially on the carton top panel and 
partially on a lateral side panel of the carton. The opening arrangement 
comprises a lug which is an integral part of the material of the packing 
container but which is delimited by a weakening or perforated line which 
extends onto portions of both the top and side panels. To prevent the 
contents of the package from leaking out through the perforation holes and 
weakening line, a cover layer is provided underneath the openable part. 
The cover layer consists of a strip of plastic film and is joined to the 
inside of the laminated packaging material (the side facing towards the 
inside of the package) in a continuous sealing zone which extends between 
the edge line of the cover layer and the perforation line. The opening 
arrangement further comprises a flexible material strip situated between 
the cover layer and the packaging laminate. The material strip is 
positioned within the sealing zone in which cover layer is joined to the 
packing laminate. The main part of the flexible material strip is situated 
underneath and extends parallel with the top end surface while a front end 
of material strip extends over the edge dividing top and side panels. The 
material strip is manufactured from a flexible resilient and relatively 
stiff plastic material which after deformation or folding directly 
reassumes its original form. The outer edge of strip is folded at 
intersection line prior to the opening of lug. However, after the lug is 
opened, the strip extends outward to provide a pouring edge. A pouring 
opening is provided in the flexible strip and an upper portion of cover 
layer directly below the opening is adhered to the lower surface of lug 
whereby it is torn free from layer when the lug is opened, allowing 
passage of liquid through the opening. 
Christensson, U.S. Pat. No. 3,613,986, discloses a liquid container having 
a cardboard outer container formed from a carton blank and a inner plastic 
liner. The carton has side panel portions each having two end flaps which 
are separated by cutouts and which are inwardly foldable to define a 
rectangular box configuration. On an inner most top flap is formed a 
pouring opening comprising a hole through the cardboard and the plastic 
liner and a pair of additional plastic layers, one on the inside of the 
opening and one on the outside of the opening. The additional pair of 
plastic layers are welded to each other at the opening. A grip tongue is 
provided for tearing away parts of the two additional plastic layers. 
Meyer-Jagenberg, U.S. Pat. No. 3,127,082, discloses a generally rectangular 
container of paper cardboard or the like consisting of a tubular body, the 
ends of which are provided with closures. One of the closures is a roof 
shaped bellows fold closure. In the region of one of the inwardly folded 
gable portions of such closure, a pouring aperture 2 is provided. Pouring 
aperture may be formed by punching end portion 1. 
Farfaglia et al, U.S. Pat. No. 3,825,408 discloses a hot air heater for 
heat sealing a thermoplastic coated, paperboard milk carton. 
Frydendal, U.S. Pat. No. 4,300,969 discloses a laminate for use in cartons 
for milk, etc. consisting of a cardboard web, a layer of heat sealable 
thermoplastic material such as polyethylene on the side of the laminate 
forming the outside of the cartons and three layers of plastic material on 
the other side, the inner most layer of which may be colored. 
Rausing et al, U.S. Pat. No. 3,347,444 discloses a generally rectangular 
container having a pouring spout formed by tearing out a portion of an end 
wall flap. 
A problem inherent in prior art configurations has been that a carton 
design capable of providing an adequate pouring spout has either required 
an elaborate fabrication procedure or must be provided in a shape which 
does not lend itself to easy, convenient and space-saving storage and 
packaging. Another problem with prior art containers has been that the 
milk carton blank configurations have required elaborate cutting, folding, 
and sealing operations to provide a liquid tight container. 
SUMMARY OF THE INVENTION 
The present invention comprises a milk carton blank having a generally 
rectangular configuration which is formed from a unitary sheet of 
laminated composite material. The laminated composite material may 
comprise an inner layer of paper material; a first layer of plastic 
material bonded to one side of the paper material by a first adhesive 
layer and a second layer of plastic material bonded to a second side of 
the paper material by a second adhesive layer. The first plastic layer may 
be back printed with predetermined carton display graphics and the second 
plastic layer may be back printed with predetermined interior side 
graphics such as a white ink used to produce a white interior appearance. 
The milk carton blank has a series of longitudinal and transverse fold 
lines provided thereon which forms a rectangular grid work dividing the 
blank into first, second, third, fourth and fifth longitudinal portions 
which, in one embodiment, have first and third relatively narrow width 
longitudinal portions and second and fourth relatively large width 
longitudinal portions, and a fifth extremely narrow edge flap longitudinal 
portion. Upper and lower transverse fold lines divide each of the 
longitudinal portions into top, middle and bottom portions respectively, 
thus defining fifteen (15) rectangular milk carton panels. Four of the top 
and bottom panels are provided with laterally, symmetrically positioned 
rectangular cutout portions therein in one embodiment of the invention. 
The cutouts may be provided in the top and bottom second and fourth 
longitudinal portions or in another embodiment, in the top and bottom 
first and third longitudinal portions. Diagonal fold lines are included in 
each of the top and bottom portions containing the rectangular cutouts and 
co-act with the cutouts when the carton blank is folded to form 
trapezoidal tongues. In a first folding sequence, the milk carton blank is 
sealed in an open ended rectangular tubular configuration by overlapping 
sealing engagement of the fifth longitudinal edge flap portion and the 
first longitudinal portion. In further folding sequences, the top and 
bottom portions of the blank are folded into a first planar configuration 
having top and bottom overlapping seams which are fixedly sealed together 
and which form two outwardly extending trapezoidal tongues. The parts of 
the blank forming the tongues are next folded inwardly to form a second 
planar configuration which is again sealed to form a liquid-tight, 
parallelepiped shaped container. 
In another embodiment of the invention, one of the cutout portions is 
replaced by a perforated tab portion which forms a triangular projection 
at one end of a tongue during the first planar sealing operation described 
above. In this embodiment, in the subsequent planar sealing operation, the 
tongue portion containing the perforated tab portion is loosely sealed in 
parallel planar relationship with the top of the milk container carton. In 
use, the tongue may be pivoted upwardly and outwardly away from the milk 
container top and the perforated tab may then be ripped off to create a 
pouring spout. In this embodiment of the invention, further folding lines 
may be provided allowing a top and side wall portion of the container to 
be thrust outwardly by squeezing the container sidewalls to further 
facilitate the operation of the pouring spout. In this embodiment, as in 
the previously discussed embodiment, the cutout and pouring spout portion 
may be provided in any two longitudinal portions of the milk carton which 
are positioned in opposed relationship when the carton blank is folded 
into the open ended tubular configuration. Thus, a pouring spout may be 
provided in association with either a wide wall or a narrow wall portion 
of the milk carton. 
The perforated tab portion of the milk carton is constructed and arranged 
whereby it initially forms a liquid tight seal which may be subsequently 
ruptured by tearing to form an open pouring spout. 
It is among the objects of the present invention to provide a milk carton 
which may be easily stored in a relatively small space. 
It is also among the objects of the present invention to provide a milk 
carton blank in a configuration which allows a number of cartons formed 
from the milk carton blank to be packaged and sold as a compact unit in a 
packaging configuration occupying a relatively small amount of space. 
It is a further object of the present invention to provide milk cartons 
which are relatively inexpensive to produce. 
It is a further object of the present invention to provide milk cartons 
having attractive external graphics which are resistant to surface 
abrasion.

DETAILED DESCRIPTION OF THE INVENTION 
The present invention comprises a milk carton blank 10, FIG. 1, which may 
be folded and sealed to produce a container 20 for milk or the like having 
a right regular parallelepiped shape or, more colloquially, a rectangular 
box-like shape as illustrated by FIG. 5. 
FIG. 1 illustrates the milk carton blank 10 of the present invention viewed 
from the surface which becomes the exterior surface of the carton 20 after 
the folding and sealing operations have been performed. The carton 
comprises four peripheral edge surfaces including a left side edge 22, a 
right side edge 24, a top edge 26, and a bottom edge 28. Edges 22 and 24 
are perpendicular to edges 26 and 28 defining a rectangle. The 
designations of left, right, top and bottom are arbitrary and are used 
herein only for purposes of reference. 
First, second, third and fourth longitudinal fold lines 32, 34, 36, 38 are 
provided running from top edge 26 to bottom edge 28 in perpendicular 
relationship thereto. Upper and lower transverse fold lines 42, 44 are 
provided extending from side edge 22 to side edge 24 in perpendicular 
relationship thereto. The fold lines may be provided by conventional 
creasing methods and apparatus well known in the art. The longitudinal 
fold lines divide the carton into first, second, third, fourth and fifth 
(left, front, right, back, and edge flap, respectively) longitudinal 
portions 50, 52, 54, 56, 58. The first longitudinal portion 50 is 
identical in width to the third longitudinal portion 54 and the second 
longitudinal portion 52 is identical in width to the fourth longitudinal 
portion 56. The fifth longitudinal portion 58 is substantially narrower 
than the other longitudinal portions. The transverse fold lines 42, 44 
divide the carton into upper, middle and lower transverse portions 62, 64, 
66. Opposite portions of upper and lower transverse portions 62, 66 have 
identical lengths, the length of portions 62, 66 being substantially 
shorter than the length of middle transverse portion 64. As used herein, 
"length" refers to a dimension extending parallel the longitudinal fold 
lines and "width" refers to a dimension extending perpendicular to the 
longitudinal fold lines. 
The grid formed by the longitudinal and transverse fold lines divide the 
carton into left lateral side panel 70, left top panel 71, left bottom 
panel 72, front lateral side panel 73, front top panel 74, front bottom 
panel 75, right lateral side panel 76, right top panel 77, right bottom 
panel 78, back lateral side panel 80, back top panel 81, back bottom panel 
82, edge flap lateral side panel 85, edge flap top panel 86, and edge flap 
bottom panel 87. Panels 71, 72, 77 and 78 comprise longitudinally outer 
edge surfaces 96, 97, 98, and 99, respectively. Right angle cutout 
portions 91, 92, 93, 94 are provided in panels 74, 75, 81, and 82 
respectively. The cutout portions 91, 92, 93, 94 each comprise an 
outwardly positioned longitudinal edge surface 102, 103, 104, 105, an 
inwardly positioned longitudinal edge surface 106, 107, 108, 109 and a 
transversely extending edge surface 110, 111, 112, 113 connecting and 
perpendicular to associated outwardly and inwardly positioned longitudinal 
edge surfaces 102 and 106, etc. The cutout portions are constructed and 
arranged such that the cutouts are identical in size and shape and the 
length of a cutout longitudinal edge surface is less than the width of a 
cutout transverse edge surface but greater than one half the width, i.e. 
1/2W L W where W is the width and L is the length. This arrangement 
produces an overlapped seam 220 as illustrated in FIG. 3 and described in 
further detail hereinafter. 
Diagonal fold lines 120-127 are provided between the corners 130-137 formed 
by two associated longitudinally extending edge surfaces 102, 106 etc. and 
the associated transverse edge surface 110 etc. of each cutout portion and 
an adjacent longitudinally inwardly positioned corner 140-147 of an 
associated panels 74, 75, 81, 82. The construction and arrangement of 
panel portions 74, 75, 81, 82 and cutouts 91, 92, 93, 94 are such that the 
diagonal fold lines bisect associated right angles at corners 140-147 
forming two 45.degree. angles, x and y, as illustrated at corner 140 in 
FIG. 1. The diagonal fold lines divide each of panels 74, 75, 81, 82 into 
a mid-section A, an outer wing section B, and an inner wing section C. 
Each wing section B, C is bordered by portions of a longitudinal folding 
line which define a wing longitudinal folding edges 150-157. Each wing 
section B, C is also bordered by a portion of upper edge 26 or lower edge 
28 which defines a wing outer edge 160-167. Each middle section A has a 
regular trapezoidal shape having a larger base 170-173 formed by an 
associated portion of upper or lower transverse line 42, 44 and a smaller 
base formed by associated cutout portion transverse edge surface 110, 111, 
112, 113. 
As illustrated by the cross sections of FIGS. 6 and 7, the material from 
which the blank 10 is formed is preferably a composite material having a 
first surface 11 which after folding forms the exterior surface of the 
carton 20, and a second surface 12 which after folding forms the interior 
surface of the carton 20. 
As illustrated in FIG. 6, in the preferred embodiment both interior and 
exterior surfaces 11, 12 comprise a layer of plastic sheet material 13, 
14. Layer 13 is bonded to one side of a paperboard material 17 by a 
suitable adhesive layer 15. The other plastic layer 14 is bonded to the 
opposite side of the paperboard 17 by a second adhesive layer 16. Both 
plastic layers 13, 14 are preferably printed on the inside surfaces 18, 19 
thereof prior to lamination with the paperboard 17. The plastic layer 13 
at the interior surface 12 of the carton 20 provides an impervious vapor 
and liquid barrier preventing a food product stored in the container from 
penetrating into paperboard 17. The plastic layer 14 at the exterior 
surface 11 of the carton provides an abrasion resistant surface. Back 
printing of the inside surfaces 18, 19 of the plastic layers may be used 
to enhance the appearance of both the interior and exterior surfaces of 
the package. For example, white ink may be back-printed on plastic layer 
14 to provide a package with a white interior appearance and various 
trademark and display type graphics may be back-printed on plastic layer 
13 to create an attractive exterior appearance. 
The exterior plastic layer 13 may be linear, low strength blends, or 
coextrusions, of low density polyethylene. The exterior plastic layer 14 
may also be a low density polyethylene. The adhesive may be a hot melt 
adhesive. The paperboard may be a natural Kraft board. The method of 
creating a plastic paper laminated composite and materials therefore 
suitable for the purposes of this invention are described in Peer, Jr. 
U.S. Pat. No. 4,254,173 which is hereby incorporated by reference for all 
that it contains. 
As illustrated in FIG. 7, a carton may also be constructed from a composite 
having a single plastic layer 14 provided on the interior surface 12 of a 
carton 20. In this embodiment the plastic layer 14 is secured to one 
surface of a paperboard sheet 17 by an adhesive layer 16 in the same 
manner as described in the Peer patent. In this embodiment the opposite 
side of the paperboard 17 is not laminated and forms the exterior surface 
11 of the carton. The exterior surface 11 may be conventionally printed 
with display graphics and the like and the plastic layer A may be back 
printed as described above. 
In other embodiments (not shown materials having either a plastic material 
on the interior or exterior or both face surfaces or any liquid impervious 
layer of material may be used. The operations used in folding and sealing 
the blank 10 to provide a milk carton 20 are illustrated in FIGS. 2 
through 5. The blank 10 is initially folded into a rectangular tubular 
configuration by folding each of the longitudinal portions 50, 52, 54, 56, 
58 into right angle relationship with the adjacent longitudinal 
portion(s). Portion 58 is positioned in overlapping relationship with 
portion 50. In another embodiment (not shown) portion 50 overlaps portion 
58. The folding between the longitudinal portions takes place along 
longitudinal fold lines 32, 34, 36, 38. The blank is thereafter sealed 
along seal line 150 (which may be as wide as the overlap) affixing portion 
50 to portion 58. In a preferred embodiment, the carton is constructed of 
the paper plastic composite illustrated in FIG. 6, and seals are made by 
hot air, ultrasonic, radiation or other well known melting and/or welding 
process or by adhesives which bond opposite plastic surfaces of 
overlapping portions of the blank to one another. When cartons are used 
which do not have plastic on both face surfaces, as in FIG. 7, the seals 
are made by any adhesive bonding of opposed surfaces together. 
As illustrated by FIG. 3 the upper and lower portions 62, 66 of the blank 
are next folded into a planar perpendicular relationship with the lateral 
side surfaces by movement of panel mid-sections 74A, 75A, 81A, 82A in a 
laterally outward direction causing inward folding of the wing portions B 
and C of each associated panel 74, 75, 81, 82 about the associated 
diagonal fold lines 120-127. The panel portions 74, 75, 81, 82 are 
constructed and arranged such that the wing portions B, C when folded 
inwardly comprise an overlapping configuration having an identical shape 
to the mid-portion A. As discussed above, the length of each cutout 
longitudinal edge portions 102, 106, etc. is greater than one half the 
width of an associated cutout transverse edge portion 110, etc. portion. 
The length of each panel portion 74, 75, 81, 82 having a cutout therein is 
greater than one half of its width. Each folded panel 74, 75, 81, 82 forms 
a multilayered trapezoidal tongue 202, 204, 206, 208. In the embodiment 
illustrated in FIGS. 3-5 left top panel 71 and associated wings 74B, 81B 
is folded inwardly slightly before right top panel 77 and associated wings 
74C, 81C. A straight outer seam line 220 comprising edges 161, 89, and 164 
and a straight inner seam line 221 comprising edges 96, 160, and 165 are 
thus formed by this sequence of folding. (Of course, the order of folding 
could be reversed in which case the upper edges of left top panel 71 and 
associated wings would form the outer seam.) Folding at the bottom portion 
of the blank, FIG. 3A, is provided in an identical manner to produce 
overlapped outer seam 222 comprising edges 163, 99, and 166 and inner seam 
223 comprising edges 97, 162 and 167. A top seal 230 is provided between 
seams 220 and 221 in generally parallel relationship therewith. Seal 232 
is similarly positioned between seams 222 and 223 at the carton bottom. 
Although shown figuratively as straight lines, the seals 230, 232 may 
extend over the entire width of the overlap. The laterally extending 
trapezoidal tongues 202, 204, 206, 208 formed from panels 74, 75, 81, 82 
are next folded inwardly as illustrated by FIGS. 4 and 5. The altitude of 
the trapezoidal mid portion A of each of panels 74, 75, 81, 82 in the 
preferred embodiment comprise a length equal to one half the width of 
lateral side panels 70 and 76. Thus when the trapezoidal shaped panels 74, 
75, 81, 82 are folded inwardly the inward edges thereof are positioned in 
abutting or near abutting contact forming seams 240, 242. As illustrated 
by FIG. 5, seal lines 244, 246, 248, 250 are provided perpendicular to 
seams 240, 242 fixedly sealing the wings 202, 204, 206, 208 to associated 
panels 71, 72, 77, 78 to complete carton 20. 
In a typical application of the embodiment of the invention illustrated in 
FIG. 1 wherein it is used as a one quart milk container, the transverse 
dimension of the milk carton blank between edges 22 and 24 is 13.000 
inches; the transverse dimension of the first and third longitudinal 
portions of the carton is each 2.500 inches; the transverse dimension of 
the second and fourth longitudinal portions of the carton are each 3.750 
inches; the transverse dimension of the fifth longitudinal portion of the 
carton is 0.500 inches; the total longitudinal dimension of the carton 
between edges 26 and 28 is 10.500 inches; the top and bottom transverse 
portions of the carton each have a longitudinal dimension of 2.125 inches 
and the middle transverse portion has a dimension of 6.250 inches; each 
cutout portion has a transverse dimension of 1.250 inches and a 
longitudinal dimension of 0.875 inches. 
In another embodiment of the invention as illustrated in FIG. 8, upper and 
lower transverse fold lines 42, 44 are provided in a discontinuous, 
slightly offset arrangement. In this arrangement, the portions of the 
upper fold lines 42-1, 42-3, 42-5 which are positioned within the first, 
third and fifth longitudinal portions of the carton, are located slightly 
inwardly of the portions of the fold line 42-2, 42-4 which are positioned 
within the second and fourth longitudinal portions of the carton. 
Similarly, portions of the lower fold line 44-1, 44-3, 44-5 positioned 
within the first, third and fifth longitudinal portions of the carton are 
located inwardly of the portions of the fold line 44-2, 44-4 positioned 
within the second and fourth longitudinal portions of the carton. This 
arrangement facilitates folding of the various panel members, making 
adjustments for the thickness of the carton material. Of course, the 
amount of offset, i.e. the longitudinal distance between one portion of a 
transverse fold line and another portion, will be dependent upon the 
thickness of the associated carton blank, and in most cases will be 
greater than or equal to that thickness. For clarity, reference numerals 
other than those indicating transverse folding line portions have not been 
included in FIG. 8. However, the embodiment of FIG. 8, with the exception 
of discontinuous transverse fold lines 42, 44, is identical to the 
embodiment of FIG. 1. In a typical use of the embodiment of the invention 
as illustrated in FIG. 8, the dimensions may be identical to the 
dimensions as described above with reference to FIG. 1, except that 
transverse line portions 42-1, 42-3 and 42-5 are positioned inwardly of 
transverse line portions 42-2 and 42-4, a distance of, for example, 0.125 
inches. 
As illustrated in FIGS. 9, 10, 11 and 12, the milk carton blank of FIG. 1 
may be provided in a configuration which is foldable into a carton having 
a pouring spout 300, by the addition of folding lines 310, 312, 314, 316 
and use of a perforated tab portion 308 in place of cutout portion 91. The 
remainder of the carton blank of FIG. 9 is identical to that of FIG. 1 
and, again, many reference numerals have been excluded for purposes of 
clarity. A diagonally extending pour spout left upper fold line 310 is 
provided, extending between the lower left corner of left top panel 71 and 
the lower left corner of the perforated portion 308. Pour spout right 
upper fold line, 312, is provided extending between the lower right corner 
of top right panel 77 and the lower right corner of perforated tab portion 
308. A pour spout left central fold line 314 is provided extending between 
a left lower corner portion of front lateral side panel 73 and a mid 
portion of a transverse perforation line 366 of perforated tab portion 
308. A pour spout right central fold line 316 is provided, extending 
between the lower right corner of front lateral side panel 73 and a mid 
portion of transverse perforation line 366. Fold lines 310 and 314 are, 
respectively, mirror images of fold lines 312 and 316 about the central 
longitudinal axis (not shown) of the front panels 73, 74. 
The fold lines 310, 312, 314 and 316, in conjunction with the previously 
described longitudinal and transverse fold lines, the peripheral edge 
surfaces of the blank, and the perforation lines of the tab portion 308, 
further subdivide the milk carton into the following panel portions: left 
top panel trapezoidal portion 330; left top panel triangular portion 332; 
front top panel left outer trapezoidal portion 334; front top panel left 
triangular portion 336; front top panel left inner trapezoidal portion 
338; front top panel central trapezoidal portion 340; front top panel 
right inner trapezoidal portion 342; front top panel right triangular 
portion 344; front top panel right outer trapezoidal portion 346; right 
top panel triangular portion 348; right top panel trapezoidal portion 350; 
front lateral side panel left triangular portion 352; front lateral side 
panel trapezoidal portion 354; front lateral side panel right triangular 
portion 356. 
The perforated tab portion 308 is laterally symmetrically positioned within 
front top panel 74 having spaced-apart left and right longitudinal 
perforation lines 362, 364, extending perpendicularly inwardly from upper 
peripheral edge 26 and having a transverse perforation line 366 extending 
between longitudinal perforation lines 362, 364 in substantially 
perpendicular relationship therewith. A left diagonal fold line extension 
368, which is an extension of diagonal fold line 120, and a right diagonal 
fold line extension 370, which is an extension of diagonal fold line 121, 
extend into the tab portion 308 intersecting and terminating at diagonal 
fold line intersection point 372. In one preferred embodiment, a 
triangular cutout portion 375 is provided by cutting inwardly from the 
upper peripheral edge 26 along projections of left and right diagonal fold 
line extensions 368, 370 to form diagonal edge surfaces 369, 371 
respectively, and to define perforated tab portion left upper edge 374 and 
right upper edge 376. The fold lines 368, 370, perforation lines 362, 364, 
366 and diagonal edge surfaces 369, 371 thus define perforated tab left 
portion 380, middle portion 382 and right portion 384. 
Perforation lines 362, 364, 366 are preferably provided by piercing outer 
plastic layer 13, adhesive layer 15 and a portion of paper layer 17 
leaving the remainder of paper layer 17, adhesive layer 16 and plastic 
layer 14 in tact, FIG. 6. In this arrangement, the carton may be torn 
relatively easily along the perforation lines and yet retains its liquid 
barrier properties due to the fact that interior plastic layer 14 has not 
been punctured. 
The carton blank illustrated in FIG. 9 may be folded and welded into the 
pour spout container illustrated in a pouring configuration in FIGS. 10 
through 12 by the folding and welding sequence illustrated in FIGS. 13 
through 16. As shown by FIGS. 13 through 16, the folding sequence of the 
carton is identical to that described above with respect to FIGS. 2 
through 5 but with the tab portion 308 forming a triangular projection at 
the end of one of the tongues 202. Sealing in wing portion 202 is 
provided, initially, only between overlapping layers of the carton 
allowing fluid communication within the sides of an envelope defined by 
intersealed portions 334, 336, 344, 346, 380, 384, on one side and 
portions 338, 340, 342, 382 on the other side. Although a single line weld 
may be provided along the line illustrated generally by the numeral 220, 
in a preferred embodiment, the carton is welded along the entire 
overlapping layer. A further welding may be provided at the tab portion to 
cause adhesion of all touching tab portion layers. As illustrated by FIG. 
15, wing 206 is folded inwardly prior to the folding of wing 202, thus 
causing tab portion 308 to be positioned at the exterior of the carton 
when folding is completed, as illustrated in FIG. 16. Since the wing 
portion 202 containing the perforated tab portion 308 must be folded 
outwardly after sealing to form the pouring spout 300 illustrated in FIGS. 
10 through 12, the attachment of wing portion 202 to panel portions 71, 77 
of a sufficiently weak to allow the wing portion 202 to be pulled away 
from surfaces 71, 77 without rupture the milk carton. Thus, in a preferred 
embodiment, a relatively low strength adhesive is used to bond wing 202 to 
surfaces 71, 77. The bonding of wing 206 to surfaces 71, 77 may be 
provided in a similar manner, although in a preferred embodiment wing 206 
is sealed to portions 71, 77 by a bond of a substantially greater strength 
than that used to seal wing portion 202 thereto. In use, as illustrated by 
FIG. 17, wing 202 is pulled away from surfaces 71, 77 as by a person' s 
grasping portion 308 and pulling upwardly and outwardly thereon. Tab 
portion 308 is next ripped from wing portion 202 as illustrated in FIG. 
18. Thereafter, the carton is urged into the configuration shown in FIG. 
19 and in greater detail in FIGS. 10, 11, and 12 by application of inward 
pressure on the carton left and right lateral side surfaces 70 and 76. The 
carton may thereafter be urged back into the configuration illustrated in 
FIG. 18 by inwardly directed pressure on front and back lateral side panel 
portions 73, 80, thus forming a nominal seal at the formerly open spout 
300. 
Thus, it may be seen that a milk carton 20 having a right regular 
parallelepiped shape may be formed from a unitary milk carton blank 10. In 
one configuration, the carton may be provided with a pour spout formable 
entirely from the unitary carton blank 10. 
Of course a folding configuration and/or milk spout configuration of the 
same type as described above may be provided in a 90.degree. rotated 
arrangement by placement of the cutout portions and/or the perforated 
spout portion in the left and right top and bottom panels 71, 72, 77, 78 
rather than the front and back top and bottom panels 74, 75, 81, 82. A 
carton blank of such a configuration is illustrated in FIG. 20 in which 
cutouts 391, 392, 394 are provided in panels 71, 72, 78 respectively, and 
perforated tab portion 396 with tab cutout 397 are provided in panel 
portion 77. The relationship of the fold lines and the cutout and 
perforated portions to the left and right longitudinal blank portions is 
the same as the relationship which these portions occupied with respect to 
the front and back longitudinal portions in the embodiments described 
hereinbefore with reference to FIGS. 9-12. In a typical application using 
the type of blank illustrated in FIG. 20 to form a one quart milk carton, 
the overall transverse dimension of the blank is 13.000 inches; panel 
portions 85, 86, 87 have a transverse dimension of 0.500 inches; panel 
portions 70, 71, 72 and 76, 77, 78 have a transverse dimension of 2.500 
inches; panel portions 73, 74, 75 and 80, 81, 82 each comprise a 
transverse dimension of 3.750 inches; the transverse dimension of cutouts 
391, 392 and 394 are each 0.500 inches and the transverse dimension of the 
perforated portion 396 is 0.844 inches; the total longitudinal dimension 
of the blank is 9.250 inches; panel portions 86, 87, 74, 75 and 81, 82 
each have a longitudinal dimension of 1.600 inches and panel portions 71, 
72, 77, 78 each have a longitudinal dimension of 1.500 inches. Cutouts 
391, 392 and 394 each have a longitudinal dimension of 0.500 inches and 
perforated portion 396 has a longitudinal dimension of 0.750 inches with 
cutout 397 having a transverse dimension of 0.368 inches. 
The folding, sealing and use sequence for the embodiment illustrated in 
FIG. 20 is identical to that illustrated in FIGS. 13 through 19, except 
that the relative position of the folding flaps and/or pouring spout is 
rotated 90.degree., so that pouring take place at one of the narrower 
longitudinal portions of the carton 20.