Method and composition providing enhanced alcohol barrier for paper packaging applications

Abstract

The methods and compositions of the present disclosure pertain to a package blank, having one or more fiber containing layers and having die cut edges. The methods and compositions provide multi-surface barrier protection for alcohol and liquid permeation along multiple axis of the packaging blank. The packaging blank can have many exposed surfaces depending upon how the blank is designed and cut from a sheet or roll. The methods and compositions provide permeation protection for the entire package, including the flat surfaces and the cut edge surfaces that make liquid contact, particularly alcohol, which are found enclosed or within the finished packaging structure. This is accomplished by both coating the blanks and structural methods of cutting, die cutting, and folding techniques.

What is claimed is: 
     
         1 . A method for preparing coated packaging blanks comprising:
 a. providing a paper, wherein said paper comprises a plurality of cellulose fibers;   b. applying a surface coating said paper on at least one of a planar top surface and a planar bottom surface with at least one layer of a polymer-containing coating;   c. cutting said coated paper, such that a coated packaging blank is created that has a specific geometrical form and size and that has a plurality of side edges;   d. applying at least one layer of a side coating on at least one of said plurality of side edges of said packaging blank;   e. wherein each of said plurality of side edges has a smaller surface area as compared to a surface area of said planar top surface or said planar bottom surface.   
     
     
         2 . The method of  claim 1 , further comprising, performing one or more curing or drying steps after said applying of said surface coating. 
     
     
         3 . The method of  claim 1 , further comprising, performing one or more curing or drying steps after said applying of said side coating. 
     
     
         4 . The method of  claim 1 , wherein said paper is selected from one or more of a paper sheet and a paper roll. 
     
     
         5 . The method of  claim 1 , wherein said side coating is a dispersion coating or an emulsion coating. 
     
     
         6 . The method of  claim 1 , wherein the applying of said side coating step is selected from the group consisting of: an extrusion coating; an extrusion lamination; a dispersion coating; and an emulsion coating. 
     
     
         7 . The method of  claim 5 , wherein when said dispersion coating or emulsion coating is used, said dispersion coating or emulsion coating is selected from the group consisting of: a blade coating; an air knife coating; a roll coating; a size press coating; and a curtain coating. 
     
     
         8 . The method of  claim 1 , wherein said polymer-containing coating comprises a polyolefin. 
     
     
         9 . The method of  claim 8 , wherein said polyolefin is selected from the group consisting of: polyethylene; polypropylene; polyester; and vinyl alcohol. 
     
     
         10 . The method of  claim 5 , wherein said side coating is an acrylic coating or an acrylic-latex coating, selected from the group of polymers consisting of: polyvinyl acetate; polyurethane; styrene butadiene; poly vinyl chloride; ethyl vinyl acetate; alkyd resins; polyethylene; polyvinyl pyrrolidone; polyethylene glycol; polyester; fluro-polymers; acrylic; acrylic-latex; ethyl acrylate; and methyl methacrylate co-polymer. 
     
     
         11 . The method of  claim 10 , wherein all of said plurality of side edges are coated and both said planar top surface and said planar bottom surface are coated, such that said coated packaging blank is coated on all sides and surfaces. 
     
     
         12 . The method of  claim 2 , further comprising:
 performing one or more curing or drying steps after the applying of said side coating.   
     
     
         13 . The method of  claim 12 , wherein said one or more curing or drying steps of said polymer-containing coating is completed before the cutting step; and
 wherein said one or more curing or drying steps of said side coating is completed by applying heat and pressure.   
     
     
         14 . The method of  claim 1 , wherein the step of cutting said coated paper is done at an angle between about 30 to 140 degrees with respect to one said planar top surface or said planar bottom surface. 
     
     
         15 . The method of  claim 14 , wherein the step of cutting said coated paper is done at an angle between about 80 to 110 degrees with respect to one said planar top surface or said planar bottom surface. 
     
     
         16 . The method of  claim 1 , wherein the step of cutting said coated paper provides a shape selected from the group of shapes consisting of: a circle; a straight; a radius edge, and combinations thereof. 
     
     
         17 . The method of  claim 13 , wherein after completing the applying of said side coating by applying heat and pressure, said polymer-containing coating and said side coating are cross-linked. 
     
     
         18 . The method of  claim 1 , wherein the cutting of one or more of said plurality of side edges exposes a plurality of fibers that are unprotected from alcohol permeation. 
     
     
         19 . The method of  claim 17 , wherein the cross-linking of said polymer-containing coating and said side coating is between about 104 to 108 cross-links per nm3. 
     
     
         20 . The method of  claim 10 , wherein the applying of said acrylic coating or said acrylic-latex coating is done during one or more of the following: stacking, moving, and transporting to a package forming and converting station. 
     
     
         21 . The method of  claim 1 , wherein the applying of said polymer-containing coating is applied with weights between about 10 to 40 gsm. 
     
     
         22 . The method of  claim 1 , wherein the applying of said polymer-containing coating is applied with weights between about 10 to 30 gsm. 
     
     
         23 . The method of  claim 1 , wherein said polymer-containing coating comprises a mineral content. 
     
     
         24 . The method of  claim 1 , wherein the applying of said side coating is applied with weights between about 3 to 20 gsm per coating layer. 
     
     
         25 . The method of  claim 1 , wherein the applying of said side coating is applied with weights between about 3 to 20 gsm total for all layers. 
     
     
         26 . The method of  claim 1 , wherein at least one of said polymer-containing coating and said side coating impregnate into one or more of said plurality of cellulose fibers of said paper at one or more positions to be present between about 3 to 80 microns from a nearest edge, such that an edge horizontal is created and there is vertical permeation resistance. 
     
     
         27 . The method of  claim 13 , wherein curing temperatures are between 100° C. (212° F.) to 200° C. (392° F.). 
     
     
         28 . The method of  claim 27 , wherein said one or more curing or drying steps are performed in one or more of: hot air ovens; drying sections; and drying tunnels. 
     
     
         29 . The method of  claim 23 , wherein said polymer-containing coating has a mineral content between about 1 and 50 wt. % based on a total paper weight. 
     
     
         30 . The method of  claim 29 , wherein said polymer-containing coating has a mineral content between about 1 and 30 wt. % based on said total paper weight. 
     
     
         31 . The method of  claim 1 , wherein said plurality of cellulose fibers comprise fibers having a diameter/width between about 16-42 microns, as measured according to TAPPI T271 OM-15: “Fiber Analysis of Paper and Paperboard” or as measured according to TAPPI T233 OM-15: “Fiber Length of Pulp and Paper by Automatic Image Analysis”. 
     
     
         32 . The method of  claim 1 , wherein one or more of said polymer-containing coating and said side coating comprises one or more components selected from the group of components consisting of: binders; pigments; dispersing agents; thickeners; rheology modifiers; coalescing agents; surfactants; crosslinkers; and combinations thereof. 
     
     
         33 . The method of  claim 1 , wherein a thickness of said paper is between about 0.025 to 0.066 cm (0.010 to 0.026 inches). 
     
     
         34 . The method of  claim 1 , wherein said paper weighs between about 129 to 273 lbs/msf. 
     
     
         35 . The method of  claim 34 , wherein said paper weighs between about 129 to 173 lbs/msf. 
     
     
         36 . The method of  claim 1 , wherein a thickness of said coated packaging blank corresponds to a length of a shorter side edge of said plurality of side edges if a 900 cut or no cut has been made to obtain said shorter edge;
 wherein said thickness of said coated packaging blank less than said length of said shorter side edge when a degree other than 90° is used for cutting.   
     
     
         37 . The method of  claim 1 , wherein a plurality of coated packaging blanks are created. 
     
     
         38 . The method of  claim 37 , wherein at least two of said plurality of coated packaging blanks are heat sealed together. 
     
     
         39 . A method for preparing coated packaging blanks comprising:
 a. providing a paper, wherein said paper comprises a plurality of cellulose fibers;   b. coating said paper on at least a planar top surface or a planar bottom surface with at least one layer of a polymer-containing coating;   c. curing or drying said coated paper;   d. cutting said coated paper, such that a coated packaging blank is created that has a specific geometrical form and size, and that has a plurality of side edges;   e. applying at least one layer of a side coating on at least one of said plurality of side edges; and   f. curing or drying said coated packaging blank.   
     
     
         40 . The method of item  39 , wherein the polymer-containing coating step is selected from the group consisting of: extrusion coating; extrusion lamination; dispersion coating; and emulsion coating. 
     
     
         41 . The method of  claim 40 , wherein the side coating step is selected from the group consisting of: a blade coating; an air knife coating; a roll coating; a size press coating; a curtain coating, and combinations thereof. 
     
     
         42 . The method of  claim 41 , wherein said polymer-containing coating comprises polyolefin and one or more biopolymers. 
     
     
         43 . The method of  claim 42 , wherein said one or more biopolymers are selected from the group of biopolymers consisting of: polyethylene; polypropylene; polyester; vinyl alcohol; polylactic acid; bio-polybutylene succinate (PBS); and combinations thereof. 
     
     
         44 . The method of  claim 43 , wherein at least one of said plurality of side edges is folded to prevent exposure of the plurality of cellulose fibers that are exposed by the cutting. 
     
     
         45 . The method of  claim 44 , wherein said folding of said at least one of said plurality of side edges reduces permeation of a liquid contained by said coated and folded packaging blank into said at least one of said plurality of side edges. 
     
     
         46 . The method of  claim 45 , wherein said coated and folded packaging blank forms a container for containing said liquid; and
 wherein all of said planar surfaces and said plurality of side edges that come into contact with said liquid are coated.   
     
     
         47 . The method of  claim 46 , wherein said plurality of cellulose fibers have:
 a. lengths between about of 0.5 to 6 mm;   b. diameters between about 10 to 40 microns; and   c. densities between about 225 to 675 kg/m3.   
     
     
         48 . The method of  claim 45 , wherein a pulp of said paper is selected from the group of pulp of: between about 75% to 100% of solid bleached sulphate pulp, with densities between about 0.3-0.9 g/cm 3 ; between 75-100% unbleached chemical pulps, with densities between about 0.3-0.9 g/cm 3 ; and combinations thereof, and wherein said coated and folded packaging blank having:
 a. an ISO 2493 MD Bending L & W, 15 degrees MD, mNm, in the range of 247 to 1320;   b. an ISO 2493 CD Bending L &W 15 degrees MD, mN, in the range of 94 to 510;   c. a Bending L & W, GM mN in the range of 152 to 811;   d. a Taber Movement Bending 15 degrees MD, mNm in the range of 10 to 64 degrees;   e. a Taber Moment Bending 15 degrees CD mNm in the range of 4.5 to 30 degrees;   f. a Taber Moment Bending GM, mNm in the range of 6.0 to 44; and   g. a T-541 ZDT kPa range from 310 to 259.   
     
     
         49 . The method of  claim 45 , wherein, a knife and paper blade have:
 a. a feed rate between about 10 to 160 meters per minute;   b. a line speed, including folding, between about 10 to 205 meters per minute;   c. a cutting depth between about 0.3 to 0.9 mm;   d. a blade length between about 25 to 70 mm;   e. a blade width between about 4 to 30 mm;   f. a handle length between about 90 to 160 mm;   g. a total knife length between about 125 to 210 mm; and   h. a blade thickness between about 0.4 to 1.2 mm.   
     
     
         50 . The method of  claim 45 , wherein a pulp of said paper comprises:
 a. between about 15 to 70% of bleached sulphate having a density between about 0.3 to 0.9 g/cm 3 ; and   b. between about 20 to 60% of chemical thermomechanical pulp having a density between about 0.3 to 0.8 g/cm 3 .