FIELD OF THE INVENTION

The present invention relates generally to beverage carton made from paper or paperboard and more particularly, to a liquid abseal-abhesive that is applied to an opening spout region of a beverage cartons to keep the opening spout region from being fused together during the filling process.

BACKGROUND OF THE INVENTION

This invention relates to paperboard containers of the type often used for the packaging of liquids such as milk and fruit juices. Such containers are fashioned from a unitary blank of paperboard, usually coated on both its interior and exterior forming surfaces with one or more barrier layer materials, cut and scored, erected and filled on automatic machinery to form gable top liquid packages. Such containers have a flat bottom and a gable top upper or roof section, the latter being adapted to form a pour spout when is opened. These containers are generally fused on one side of the gable top and only sealed in the opposite side (pour spout area) of the gable top liquid packages.

During the manufacturing process of the beverage cartons it is critical that only one side of the gable top is fused and the opposite side (pour spout area) is only sealed so that a user can easily open the pour spout area for dispensing the liquid. Currently, during the manufacturing process of the beverage carton, a solution is applied to the pour spout area which acts as a barrier between the polyethylene coatings of the beverage carton. This barrier prevents fusing of the polyethylene layers to one another and improves opening the pour spout area by a user.

However, one problem of this solvent solution is that it is invisible to the naked eye and could only be seen when blue dye or iodine was applied directly to the pour spout area. Another problem of this solvent solution is that it requires human resources for applying blue dye or iodine to the beverage cartons to determine if the solvent solution is applied properly. In addition, the solution may inadvertently track into the beverage carton and not be seen by the naked eye and therefore, the solvent solution which tracked into unwanted areas of the cartons causes the beverage carton to leak when filled with liquid.

Therefore, the present invention solves the above-mentioned problems.

SUMMARY OF THE INVENTION

One aspect of the present invention relates to a bank and a gable top carton constructed therefrom. The blank comprises a plurality of panels having top portions. The top portions of the plurality of panels are cooperated with one another to define a gable top. The plurality of panels are consecutively articulated to one another along parallel fold lines. At least one of the plurality of panels includes a fluorescent whitening agent on all or a portion of an inner surface of the top portion of the at least one panel. The top portion of the at least one panel glow when subjected to a black light.

Another aspect of the present invention relates to a method of producing a blank having a plurality of panels. The method comprising the steps of applying a fluorescent whitening agent on all or a portion of an inner surface of the top portion of the at least one panel of the blank and subjecting the portion of the inner surface of the top portion of the at least one panel of the blank having the fluorescent whitening agent to a black light so that top portion of the blank glow.

Yet another aspect of the invention relates to sealed carton comprising a body having a plurality of side walls consecutively articulated to one another along parallel fold lines. A plurality of panels is configured to cooperate with one another to define a gable top having first and second sides and a bottom of the sealed carton. At least one of the plurality of panels of the gable top includes a fluorescent whitening agent on all or a portion of an inner surface of the first side of the gable top in which the at least one panel glow when subjected to a black light. The second side of the gable top being fused to one another and wherein the first side of the gable top define a pour spout formed by the plurality of the panels. The pour spout is capable of periodically opened and closed to access the material stored in the carton.

BRIEF DESCRIPTION OF THE DRAWINGS

A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:

FIG. 1 is perspective view of a gable top carton in accordance with the present invention;

FIG. 2 is a view similar to FIG. 1, illustrating the manner in which the gable top is opened by a user;

FIG. 3 is similar to FIG. 1, shown the gable top carton in an opened position;

FIG. 4 is a plan view of a paperboard blank having composition of a fluorescent whitening agent and used to form the gable top carton of FIG. 1 in accordance with the preferred embodiment of the present invention; and

FIG. 5 is a side elevation view of a portion of a printing process having incorporated therein the fluorescent whitening agent storage tank, black light device, and depicting the flow of the blanks into and through the printer.

DETAIL DESCRIPTION OF THE INVENTION

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.

FIGS. 1-3 depicts a gable top carton in accordance to the present invention. The gable top carton 10 is formed from a single sheet of paperboard material that is folded to define upstanding side walls 12, 14, 16, and 18, a sealed bottom 20 and an initially sealed top 22 that is capable of being periodically opened and closed to access the material stored in the carton 10. The paperboard sheet or blank (shown in FIG. 4), from which the gable top carton 10 is formed typically is coated or laminated on both sides with a plastic and/or may also include foil on one side to prevent the material stored in the carton from leaking and to prevent liquids from wicking into the paperboard material of the carton 10.

The side walls 12, 14, 16, and 18 of the gable top carton 10 comprises a total of four rectangular side walls consecutively jointed to one another and disposed in opposed parallel pairs. One rectangular side wall is securely adhered by heat sealing to a side seam panel that is hingedly connected to an adjacent rectangular side wall panel. The bottom 20 of the gable top carton is defined by an array of bottom panels, not shown in FIG. 1, that are folded into overlapping relationship to one another and that are securely and substantially permanently sealed. The top of the gable top carton 10 includes a pair of rectangular roof panels 24, 26 that converge toward one another. Arrays of hingedly connected triangular panels 28, 30 extend between and connect the rectangular roof panels. Top seal panels 22a, 22b are articulated to the rectangular roof panels 24, 26 and to the arrays of triangular panels 28 and 30. The top seal panels 22a, 22b are secured in face to face relationship to seal the top of the gable top carton 10.

As illustrated in FIG. 2, the gable top carton 10 is opened by folding corner regions of the rectangular roof panels 24, 26 backwardly to more conveniently access one of the arrays of triangular panels 28, 30 extending therebetween. This first step of the carton opening generally can be carried out easily. The top seal panels 23a, 23b of the triangular panels are then separated from the top seal panels 22a, 22b of the rectangular roof panels 24, 26, such that the triangular panels 28, 30 can be folded outwardly to define a pour spout 32.

FIG. 4 is plan view of a paperboard blank 40 used to form the gable top carton 10 in FIGS. 1-3. The blank 40 is provided with an array of score lines or fold lines for defining a plurality of hingedly connected panels. The blank 40 includes a rectangular first side panel 42, a rectangular second side panel 44, a rectangular third side panel 46, a rectangular fourth side panel 48, and a rectangular side seam panel 50 which are consecutively articulated to one another along parallel fold lines 52, 54, 56 and 58 respectively.

The first side panel 42 is further defined by an edge 60 which extends parallel to the fold line 52. Additionally, the first side panel 42 is defined by a first bottom fold line 62 and a first top fold line 64. A first bottom panel 66 is articulated to the first side panel 42 along the first bottom fold line 62.

A rectangular first top panel 68 is articulated to the first side panel 42 along the first top fold line 64. The rectangular first top panel 68 also is defined by side edge 70 which extends collinearly from the edge 60 of the first side panel 42. The rectangular first top panel 68 is further defined by fold line 72 extending substantially collinearly from the fold line 52 and by fold line 74 extending between the edge 70 and the fold line 72 and substantially parallel to the first top fold line 64. A pour spout score line 76 extends diagonally from the intersection of the fold lines 64 and 72 to a point along the fold line 74 intermediate its length. The triangular corner defined by the pour spout score line 76 on the rectangular first top panel 68 will define a portion of the pour spout 32 on the gable carton 10 as described above.

A first exterior top seal panel 78 is articulated to the rectangular first top panel 68 along fold line 74. The first exterior top seal panel 78 is further defined by edge 80 which extends collinearly from the edge 70 and by fold line 82 which extends collinearly from the fold line 72. Additionally, the first exterior top seal panel 78 is defined by a fold line 84 extending substantially parallel to the fold line 74 and between the edge 80 and the fold line 82. A first top seal flap 86 is articulated to the first exterior top seal panel 78 along the fold line 84.

The second side panel 44 of the blank 40 is further defined by a second bottom fold line 88 and a second top fold line 90. An isosceles triangular second bottom panel 92 is articulated to the second bottom panel 44 along the second bottom fold line 88. The triangular second bottom panel 92 is further defined by converging fold lines 94 and 96. A triangular bottom web panel 98 is articulated to the first bottom panel 66 along fold line 100 and to the second bottom panel 92 along fold line 94. Similarly, a triangular bottom web panel 102 is articulated to the second bottom panel 92 along fold line 96, and is further defined by fold line 104 extending collinearly from the fold line 54. An isosceles triangular second top panel 106 is articulated to the second side panel 44 along the second top fold line 90. The triangular second top panel 106 will define a major portion of the pour spout 32 on the carton 10 formed from the blank 10. The triangular second top panel 106 is further defined by converging fold lines 108 and 110. A triangular first top web panel 112 is articulated to the rectangular first top panel 68 along fold line 72 and to the triangular second top panel 106 along fold line 108. The triangular first top web panel 112 is further defined by fold line 114 which extends substantially collinearly from the fold line 74 and parallel to the second top fold line 90. Similarly, a triangular second top web panel 116 is articulated to the triangular second top panel 106 along fold line 110. The triangular second top web panel 116 is further defined by fold line 118 which extends collinearly from the fold line 110, and by fold line 120 which extends collinearly from the fold line 114.

A first top interior top seal panel 122 is articulated to the triangular web first top panel 112 along the fold line 114 and is further articulated to the first top exterior seal panel 78 along fold line 82. A second interior top seal panel 124 is articulated to the triangular second top web panel 116 along the fold line 120. The second interior top seal panel 124 is articulated to the first interior top seal panel 122 along fold line 126 and is further defined by fold line 128 extending collinearly from the fold line 118.

The third side panel 46 is further defined by a third bottom fold line 130 and a third top fold line 132 which extend orthogonally between the fold lines 54 and 56 respectively. A third bottom panel 67 is articulated to the third side panel 20 along the third bottom fold line 65. The third bottom panel 134 is articulated to the bottom web panel 102 along fold line 104, and is further defined by fold line 136.

A rectangular third top panel 138 is articulated to the third side panel 46 along the third top fold line 132. The third top panel 138 is articulated to the triangular second top web panel 116 along fold line 118. The third top panel 138 is further defined by fold line 140 extending generally collinearly from the fold line 114 and by fold line 142 extending generally parallel to the third top fold line 132 and orthogonally between the fold lines 118 and 140. The third top panel 138 is further defined by a pour spout score line 144 which extends diagonally from the intersection of fold lines 118 and 132 to a point intermediate the length of the fold line 142. The pour spout score line 144 on the third top panel 138 generally corresponds to the pour spout score line 76 on the first top panel 68. Thus, the corner of the rectangular third top panel 138 defined by the pour spout score line 144 will define a portion of the pour spout on the carton formed from the blank 10, as described above.

A second exterior top seal panel 146 is articulated to the third top panel 138 along the fold line 142. The second exterior top seal panel 146 is articulated to the second interior top seal panel 124 along the fold line 128. The second exterior top seal panel 146 is further defined by fold line 148 extending generally collinearly from the fold line 140 and by fold line 150 extending generally parallel to the fold line 142. A second top seal flap 152 is articulated to the second exterior top seal panel 146 along the fold line 150 and will be adhered in face to face contact with the first top seal flap 86 on the carton 10 erected from the blank 10.

The fourth side panel 48 is further defined by a fourth bottom fold line 154 and a fourth top fold line 156. A triangular fourth bottom panel 158 is articulated to the fourth side panel 48 along the fourth bottom fold line 154. The fourth bottom panel 158 is triangular in shape, and is further defined by converging fold lines 160 and 162. A triangular web panel 164 is articulated to the fourth bottom panel 158 along the fold line 160 and is further articulated to the third bottom panel 134 along fold line 136. Similarly, a triangular web panel 166 is articulated to the fourth bottom panel 158 along fold line 162 and is further defined by fold line 168.

A triangular fourth top panel 170 is articulated to the fourth side panel 48 along the fourth top fold line 156. The fourth top panel 170 generally corresponds to the second top panel 106, but is not intended to be opened into the pour spout 32. The fourth top panel 170 is further defined by converging fold lines 172 and 174.

A triangular third top web panel 176 is articulated to the third top panel 138 along fold line 140 and to the fourth top panel 170 along fold line 172. The triangular third top web panel 176 is further defined by fold line 178 which extends generally collinearly from the fold line 142. A triangular fourth top web panel 180 is articulated to the fourth top panel 179 along fold line 174. The triangular fourth top web panel 180 is further defined by fold line 182 which extends generally collinearly from the fold line 58, and by fold line 184 which extends collinearly from the fold line 178. Third and fourth interior top seal panels 186 and 188 are articulated to the triangular web panels 176 and 180 along fold lines 178 and 184 respectively. The third interior top seal panel 186 is articulated to the second exterior top seal panel 146 along fold line 148 and is articulated to the fourth interior top seal panel 188 along fold line 190. The fourth interior top seal panel 188 is further defined by fold line 192.

A bottom seal panel 194 is articulated to the side seam panel 50 along fold line 196 and to the triangular bottom web panel 166 along fold line 168. Similarly, a top seal panel 198 is articulated to the side seam panel 50 along fold line 200 and to the triangular fourth top web panel 180 along fold line 182.

The blank 10 may be coated or laminated with an appropriate plastic, foil or the like to achieve sufficient impermeability. Additionally, selected regions of the panels may have heat and/or pressure applied thereto for subsequent sealing during formation of the blank 40 into the gable top carton 10.

During manufacturing and printing process of the blank 40, a liquid known as abseal-abhesive is applied to the top seal panels 22a, 22b which keep certain portions of the gable top carton 10 from being fused together during filling process. The area that the abhesive-abseal is applied to is the pour spout 32 area which is intended to by open by users. The word â€œabhesive-absealâ€ defined herein as a chemical agent which reduces adhesion of two layers but permits the two layers sealed (not fused) to one another. Moreover, the word â€œabhesive-absealâ€ also means that the chemical agent prevent leakage of liquid from the gable top carton. A new fluorescent abseal-abhesive coating is discovered by the inventor of the present invention which eliminates human involvement with the quality control inspection of the abhesive application and substantially reduces the operation cost of the blank 40. The new fluorescent abseal-adhesive coating composition comprises of abseal-abhesive and t a fluorescent whitening agent. The whitening agent is generally an optical brightener known as â€œOBAâ€ . Optical brighteners are dye-like fluorescent compounds and are substances that absorb light in the invisible ultraviolet region of the spectrum and reemit it in the visible portion of the spectrum, particularly in the blue to blue violet wavelengths. This provides added brightness and can offset the natural yellow cast of a substrate such as paper. Optical brighteners used in the present invention may vary widely and any suitable optical brightener may be used. An overview of such brighteners is to be found, for example, in Ullmann's Encyclopedia of Industrial Chemistry, Sixth Edition, 2000 Electronic Release, and OPTICAL BRIGHTENERSâ€”Chemistry of Technical Products which is hereby incorporated, in its entirety, herein by reference. Other useful optical brighteners are described in U.S. Pat. Nos. 5,902,454; 6,723,846; 6,890,454; 5,482,514; 6,893,473; 6,723,846; 6,890,454; 6,426,382; 4,169,810; and 5,902,454 and references cited therein which are all incorporated by reference. Still other useful optical brighteners are described in; and U.S. Pat. Application Publication Nos. US 2004/014910 and US 2003/0013628; and WO 96/00221 and references cited therein which are all incorporated by reference. Illustrative of useful optical brighteners are 4,4â€²-bis-(triazinylamino)-stilbene-2,2â€²-disulfonic acids, 4,4â€²-bis-(triazol-2-yl)stilbene-2,2â€²-disulfonic acids, 4,4â€²-dibenzofuranyl-biphenyls, 4,4â€²-(diphenyl)-stilbenes, 4,4â€²-distyryl-biphenyls, 4-phenyl-4â€²-benzoxazolyl-stilbenes, stilbenyl-naphthotriazoles, 4-styryl-stilbenes, bis-(benzoxazol-2-yl) derivatives, bis-(benzimidazol-2-yl) derivatives, coumarins, pyrazolines, naphthalimides, triazinyl-pyrenes, 2-styryl-benzoxazole or -naphthoxazoles, benzimidazole-benzofurans or oxanilides. A significant advantage of the fluorescent whitening agent is the glow characteristic property when subjected to a black light. Another advantage of the fluorescent whitening agent is that the agent is harmless when is in direct contact with edible liquid. Moreover, as it mentioned above, the application of the new fluorescent abseal-adhesive coating composition onto the gable top carton 10 completely eliminates the manual inspection of the carton by applying other chemical agents (e.g., dye or iodine) to make the abseal-abhesive visible. Finally, the new fluorescent abseal-adhesive coating also eliminates the possibility of abseal-abhesive being tracked into unwanted areas of the carton and being invisible which then causes the cartons to leak. The new abseal-abhesive coating composition is used in a gable top liquid carton that is made from paper or paperboard. The abseal-abhesive composition is water based liquid that may not be observed with an unaided eye during or after the manufacturing process. The amount of fluorescent whitening agent can be varied widely depending on the process. The abseal-abhesive composition is made from preferably 3% of the fluorescent whitening agent to abseal-abhesive. The mixture whitening agent to abseal-abhesive has produced an unexpected coating characteristic that is an important aspect of the invention.

The other important aspect of the present invention is the discovery of using this new chemical in the liquid packaging industries. The new abseal-abhesive composition is applied to the gable top carton to prevent the gable top portion from being fused together during the filling process. The abseal-abhesive is applied to the gable top only in the area where the liquid carton is intended to be open by a user.

A conventional printing process such as Gravure printing/Flexo printing/Dry Offset printing/rotogravure printing/the ink jet printing is used to apply the new fluorescent abseal-adhesive coating composition onto the pour spout area 32 in accordance with the preferred embodiment of the present invention.

In operation, the blanks 40 are continuously fed through a printing station 300. The printing station 300 includes a print head 302 and a backup roll 304 disposed relative to the print head 302 as to define a gap 306 therebetween. Each blank 40, on the conveyor 308, is fed forward into and through the gap 306 in a continous forward motion (depicted by arrows), with printing the desired information onto the blank 40 while in the region of the gap 306. Next, the new fluorescent abseal-adhesive coating from a storage tank 310 is applied in the region (A), (B), and (C) of the blank 40 which these regions are clearly depicted in the FIG. 4. Finally, the blank 40 is moved forward to the location where a black light device 312 is installed. At this location, the blank 40 goes under complete inspection by receiving a light ray from the black light device 312. When the light rays are projected on the blank 40, the areas such as regions (A), (B), or (C) which the fluorescent abseal-adhesive coating is applied glow accordingly.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.