WO2025019243A1 - Method and composition providing enhanced alcohol barrier for paper packaging applications - Google Patents

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.

Description

METHOD AND COMPOSITION PROVIDING ENHANCED ALCOHOL BARRIER FOR PAPER PACKAGING APPLICATIONS CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This Application claims the benefit of U.S. Provisional Application No.63/513,798, filed on July 14, 2023, entitled “METHOD AND COMPOSITION PROVIDING ENHANCED ALCOHOL BARRIER FOR PAPER PACKAGING APPLICATIONS”, the contents of which are incorporated herein by reference as though set forth in their entirety. This Application also takes priority to U.S. Non-Provisional Patent Application No. 18/768,751, filed on July 10, 2024, entitled “METHOD AND COMPOSITION PROVIDING ENHANCED ALCOHOL BARRIER FOR PAPER PACKAGING APPLICATIONS”, the contents of which are incorporated herein by reference as though set forth in their entirety and to which priority is claimed. FIELD [0002] The present disclosure relates to a method and composition providing multi-dimensional and multi-surface barrier layer(s) applied to a packaging paper blank specifically used for open top rigid packaging used for cups. The coatings may be used for the prevention of fiber discoloration and deterioration resulting from liquid or alcohol permeation. Most particularly, the present disclosure provides a method of providing finished packaging barrier protection using a coating process preventing edge cut permeation. Further, the methods used include improving cross linking density by applying post curing heat and pressure which improves barrier and adhesion performance. Although not a limitation, this method is particularly useful on foodservice cups and trays, such that they require a barrier on both flat surfaces at one angle and barrier protection on a second axis, applied to the edge cuts. Therefore, the barrier layers are applied at more than one angle (e.g., multiple fiber surfaces). The paper blanks include outer facing flat surfaces with cut edges normally die cut at ninety-degree angles, however, could also be cut in the range of about 30 to 140 degree angles from the outer facing surfaces. Additionally, the coatings can be used to prevent permeation when the inner edge of the cup blank is cut from the top and from the front edge of the blank, separating the edge into two surfaces which may then be folded and bonded before the cup is formed. Further, the coatings can provide a heat seal and alcohol barrier inside the folded and sealed edges of the finished package or cup. BACKGROUND [0003] Foodservice packaging is used for a variety of fast-food applications having short “shelf life” requirements. The packaging includes, for example, hot cups, cold cups, trays, etc. Sometimes the outer facing paper layers are coated for barrier protection and individual components are typically cut to specification from rolls and sheets, creating blanks that are then formed and sealed into finished packages. These “cut to size package parts” are known as flat “blanks”. For example, a hot cup might be comprised of a flat blank for the side wall that is then sealed and formed into a formed bottom flat blank, resulting in a completed cup. This can be the case with a wide variety of packages requiring paper blanks that are used in the forming, sealing, or gluing process. [0004] However, for one example, a paper cup sidewall blank has key shortcomings, created by the process of cutting the blanks from paper sheets by using a knife and die cutting. This non coated and exposed side section is known as the “cut edge” or “cut score line”. When the packaging blanks are formed, glued, adhered, or heat sealed, and become a finished package, the unprotected cut edge is vulnerable to barrier permeation from liquids along the cut line, thus facilitating rapid and direct permeation into the fibers. Cut edge permeation rapidly advances across the inside of the fiber structure and into the interfacial surface between the coatings and the fibers. The fibers become wet from the attacking liquid and the package begins to lose strength, reducing strength and shelf life. Also, as the liquid proceeds further into the fiber layer the compromised fibers become discolored and very unattractive to the consumer, particularly in the case of consumer liquid and food packaging. The discoloration can be placed into categories, such as grayish-black, brownish-black, bluish black, grayish- white, brownish white, bluish white. The speed of discoloration depends upon the type of paper fiber, the thickness, alcohol content, paper porosity, and fiber sizing. Examples include a cup shaped package formed from solid fiber with one or more extrusion coated polyolefin barrier coatings with paper coat weights from 10 gsm to 28 gsm, applied to one or more outer facing sides of the formed sidewall and up to two sides of the bottom cup stock. In this case, a representative sampling of cups was filled with beverage solutions containing a range of alcohol content from 10% to 55% by volume of alcohol, the alcohol having a density in the range of .77 to .82 g/cm3. The cup having a Tappi Brightness of from 85 to 95, a CIE whiteness of from 65 to 95, a fiber density of between .3 to .7 g/cml, and Elmendorf tear strength of approximately 5-25 mN, the cup paper weight ranging from 129 lbs/msf to about 273 lbs/msf with calipers from .010” to .028” and a fiber moisture content from 2% to 18%. [0005] 88 mL of an alcohol containing liquid was introduced into a representative sampling of a current cup package. The liquid permeation results were observed at 15 minutes, 30 minutes, 1 hour, 2 hours, 12 hours, and 24-hour time frames. Observations include the exterior and interior of the package on both the sidewall and bottom areas. The rate of degradation and failure criteria was determined upon the total overall average surface area on the inner side of the cup. Terminal failure identified at 5% overall average surface discoloration, a 5% overall reduction in inner surface brightness, a 5% or more reduction in inner surface whiteness, and a 5% inner wall tear strength reduction. Representative sampling observations are illustrated in Table 1 and Table 1B below. Table 1, Example % Degradation Rates (Surface Area) Time Brightness Whiteness Tear strength Discoloration

.Table 2, Alcohol Permeation Ranges Time % Permeation Volume Permeation mL

when placed into the container. SUMMARY [0006] To minimize the limitations in the prior art, and to minimize other limitations that will become apparent upon reading and understanding the present specification, the present disclosure discloses a new and useful method and composition providing enhanced alcohol barrier for paper packaging applications. [0007] The following presents a simplified overview of the example embodiments in order to provide a basic understanding of some embodiments of the example embodiments. This overview is not an extensive overview of the example embodiments. It is intended to neither identify key or critical elements of the example embodiments nor delineate the scope of the appended claims. Its sole purpose is to present some concepts of the example embodiments in a simplified form as a prelude to the more detailed description that is presented herein below. It is to be understood that both the following general description and the following detailed description are exemplary and explanatory only and are not restrictive. [0008] It is therefore the object of this disclosure to provide methods of alcohol barrier protection for single and multiple layer flat blank cut edges prior to forming and sealing the final package. Further, to act as a sealing and barrier coating for the rounded interior two cut edge and inner contact surfaces of the hemmed edge of the cup blank and internal flat contact surfaces of the hemmed edge of the cup blank structure, the coatings used in combination with paper specifications required for this use. More particularly to apply the exposed cut edge fibers with acrylic or acrylic-latex particle containing coatings from 3 gsm to 30 gsm in coat weight such that the coating better protects the outer blank edge. Also, for better performance, the cut edge coating permeates horizontally into the open fibers at depths from about 10-80 microns from the outer edge. The next step may be applying post curing heat and pressure in the cut edge areas to increase polymer cross linking density, thus creating a higher barrier performance that protrudes from the cut edge deeply into the fibers layer, therefore, greatly reducing or eliminating alcohol permeation due to edge wicking. The enhanced permeation barrier may also reduce or eliminate discoloration, adhesion, and tensile strength of the package due to alcohol permeation into the fibers. Further, the methods and compositions of the present disclosure may reduce or eliminate coating surface permeation on the flat blank planar surface interfacial areas. [0009] It is object of the present disclosure to provide paperboard containers such that all the interior and exterior surfaces have been modified in such a way that the edges provide barrier protection from alcohol permeation damage and wherein edge wicking is greatly reduced. [0010] It is a further object of the present disclosure to reduce or eliminate alcohol permeation using acrylic and acrylic-latex containing coatings that are applied to the raw cut edges of blanks. [0011] It is a further object of the present disclosure to improve cut edge barrier performance by applying post curing heat and pressure that improves coatings cross link density. [0012] It is still another object of the present disclosure to provide a novel and improved paperboard container which greatly reduces fiber discoloration from liquid edge wicking, particularly from alcohol permeation. [0013] It is still another object of the present disclosure to provide a novel and improved paperboard container that greatly reduces fiber strength loss from edge wicking. [0014] It is still another object of the present disclosure to reduce package discoloration and improving surface print quality of the package, particularly from discoloration due to alcohol permeation. [0015] It is still another object of the present disclosure to provide barrier protection to fibers from permeation originating at the interfacial layer below the coatings applied on the outer facing planar surfaces. [0016] It is still another object of the present disclosure to provide barrier protection by knife cutting the outer flat wall of the cup blank comprised of specific fiber, thickness and strength parameters, separating the paper layers, folding along the cut edge, and sealing the reverse folded contact surfaces, securing the fold on the outside of blank and thus removing the inner cut edge that was previously exposed to liquid cut edge of the blank. [0017] It is an object to overcome the limitations of the prior art. [0018] These, as well as other components, steps, features, objects, benefits, and advantages, will now become clear from a review of the following detailed description of illustrative embodiments, the accompanying drawings, and the claims. BRIEF DESCRIPTION OF THE DRAWINGS [0019] The drawings are of illustrative embodiments. They do not illustrate all embodiments. Other embodiments may be used in addition or instead. Details which may be apparent or unnecessary may be omitted to save space or for more effective illustration. Some embodiments may be practiced with additional components or steps and/or without all of the components or steps which are illustrated. When the same numeral appears in different drawings, it refers to the same or like components or steps. [0020] Fig. 1 is an illustration of a top view of a rectangular blank showing from outer planar coated surface 1 bound directly to the fiber layer 2 by polyolefin extrusion coating. [0021] Fig.2 is an illustration of a perspective view of a blank with both straight and radius edges having three layers. [0022] Fig.3 is an illustration of a top perspective view of an irregularly shaped blank having one top fiber layer planar surface 6 bound to a top coating layer and one bottom fiber planar surface 7. [0023] Fig.4 is an illustration of a cross-section view of the embodiment shown in FIG.1 of an example blank side view showing a flat planar outer facing coating layer 1 bound along the interfacial surface of outer facing fiber layer 2. [0024] Fig.5 is an illustration of a top front perspective view of a square shaped cut blank having one coating layer and one fiber layer. [0025] Fig.6 is an illustration of a perspective view of an example showing a section of the seam area after the skiving knife has cut and separated the seam in preparation for folding and sealing. [0026] Fig.7 is an illustration of a front view of the inside of the post sealed package wall blank seam area. [0027] Fig.8 is an illustration of a top view of a reverse folded sidewall package blank. DETAILED DESCRIPTION [0028] In the following detailed description of various embodiments of the present disclosure, numerous specific details are set forth in order to provide a thorough understanding of various aspects of one or more embodiments of the present disclosure. However, one or more embodiments of the present disclosure may be practiced without some or all of these specific details. In other instances, well-known methods, procedures, and/or components have not been described in detail so as not to unnecessarily obscure aspects of embodiments of the present disclosure. [0029] While multiple embodiments are disclosed, still other embodiments of the devices, systems, and methods of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the devices, systems, and methods of the present disclosure. As will be realized, the devices, systems, and methods of the present disclosure are capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present disclosure. Accordingly, the screenshot figures, and the detailed descriptions thereof, are to be regarded as illustrative in nature and not restrictive. Also, the reference or non-reference to a particular embodiment of the devices, systems, and methods of the present disclosure shall not be interpreted to limit the scope of the present disclosure. [0030] Before the present methods and systems are disclosed and described, it is to be understood that the methods and systems are not limited to specific methods, specific components, or to particular implementations. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. [0031] As used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. [0032] “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not. [0033] Throughout the description and claims of this specification, the word “comprise” and variations of the word, such as “comprising” and “comprises,” means “including but not limited to,” and is not intended to exclude, for example, other components, integers or steps. “Exemplary” means “an example of” and is not intended to convey an indication of a preferred or ideal embodiment. “Such as” is not used in a restrictive sense, but for explanatory purposes. [0034] Disclosed are components that may be used to perform the disclosed methods and systems. These and other components are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these components are disclosed that while specific reference of each various individual and collective combinations and permutation of these may not be explicitly disclosed, each is specifically contemplated and described herein, for all methods and systems. This applies to all embodiments of this application including, but not limited to, steps in disclosed methods. Thus, if there are a variety of additional steps that may be performed it is understood that each of these additional steps may be performed with any specific embodiment or combination of embodiments of the disclosed methods. [0035] The present methods and systems may be understood more readily by reference to the following detailed description of preferred embodiments and the examples included therein and to the Figures and their previous and following description. [0036] In the following description, certain terminology is used to describe certain features of one or more embodiments. For purposes of the specification, unless otherwise specified, the term “substantially” refers to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, in one embodiment, an object that is “substantially” located within a housing would mean that the object is either completely within a housing or nearly completely within a housing. The exact allowable degree of deviation from absolute completeness may in some cases depend on the specific context. However, generally speaking, the nearness of completion will be so as to have the same overall result as if absolute and total completion were obtained. The use of “substantially” is also equally applicable when used in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result. [0037] As used herein, the terms “approximately” and “about” generally refer to a deviance of within 5% of the indicated number or range of numbers. In one embodiment, the term “approximately” and “about”, may refer to a deviance of between 0.001-10% from the indicated number or range of numbers. [0038] Various embodiments are now described with reference to the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that the various embodiments may be practiced without these specific details. In other instances, well- known structures and devices are shown in block diagram form to facilitate describing these embodiments. [0039] The methods and compositions of the present disclosure are designed to, and do, provide improved functional barrier performance along multiple cut blank surface axis and cut blank cut edge protection across and inside the score line perimeter, the method and composition comprised of the following steps: [0040] Step 1: Coat on one or two sides a paper sheet or roll with polymer containing coating(s), the coating(s) applied on the flat outer facing planar surfaces of the roll or sheet to include extrusion coating or extrusion lamination, dispersion, or emulsion coatings. The dispersion and emulsions coating methods include blade coating, air knife coating, roll coating, size press coating, curtain coating. [0041] Step 2: Apply acrylic or acrylic-latex dispersion or emulsion coatings and other coatings comprised of the chemicals described herein, on the cut score edge at approximately 90-degree angle. However, depending on die design, applied in the range of 30 to 140 degrees, from the flat planar surface of the blank. The coating is applied and cured at the cut blank edges, the edges having exposed fibers that are unprotected from alcohol permeation. This coating application is done during the process of blank stacking, moving, or transporting to the package forming and converting station. The acrylic or acrylic-latex barrier containing coatings are applied with weights from 3 gsm to 20 gsm. The coating then seeps into the fibers to about 3 to 80 microns from the cut edges, creating cut edge horizontal as well as vertical permeation resistance. The coating can be applied using spray, single and multiple rollers, pads, flexible plates, and cylinders among many other techniques know to the art. Depending upon the coating formulation a drying and curing station could be located after the coating material is applied to the fiber, curing temperatures between approximately 100°C (212°F) to 200°C (392°F) in hot air ovens, drying sections, or drying tunnels. Upon coating application, the packaging blank has 360-degree barrier protection along two axes, diminishing or preventing liquid permeation. After curing the first coatings have been completed, post curing heat and pressure is applied to the edge trim area into the interior fibers to up to about 0.5” from the outer edge of the blank, therefore, cross linking density improvements are achieved along a wide area including the exposed edge and the interior fibers of the blank including the interfacial surface. [0042] During the above stated step, other chemicals and other ingredients can be mixed or used alone and applied to the package surface as part of the coatings. They include the chemical components of dispersion and emulsion coatings such as: [0043] Binders. The binder is the primary film-forming component of the coating. It provides adhesion and cohesion to hold the coating together. Common binder types used in dispersion and emulsion coatings include pigments, acrylics, styrene-butadiene (SB) latex, polyvinyl acetate (PVA), and polyurethane. Pigments can be organic or inorganic, such as titanium dioxide, iron oxides, carbon black, phthalocyanines, and many others. [0044] Dispersing Agents. Dispersing agents are chemicals added to the coating formulation to ensure proper dispersion and stabilization of the pigments or other solid particles. They help prevent settling or clumping of the particles, ensuring uniform distribution within the coating. Common dispersing agents include polymeric dispersants and surfactants. [0045] Thickeners or rheology modifiers may be added to control the viscosity and flow characteristics of the coating. They help achieve the desired consistency and prevent sagging or running during application. Common thickening agents include cellulose derivatives, acrylic thickeners, and associative thickeners. [0046] Coalescing agents. Coalescing agents may be added to aid in the film formation process of dispersion and emulsion coatings. They promote the fusion of polymer particles during drying, leading to the formation of a continuous film. Common coalescing agents include glycol ethers, such as ethylene glycol monobutyl ether (EGBE) or propylene glycol ethers. [0047] Surfactants. Surfactants are surface-active agents that help to stabilize emulsions or dispersions by reducing surface tension and preventing coagulation or flocculation of particles. They assist in maintaining stability and ensure uniform coating properties. Non-ionic, anionic, or cationic surfactants can be used depending on the specific coating requirements. [0048] Crosslinkers. In some cases, crosslinkers may be added to improve the durability and chemical resistance of the coating. Crosslinkers promote the formation of chemical bonds between polymer chains, enhancing the coating's performance characteristics. Examples of crosslinkers include melamine-formaldehyde resins, isocyanates, and epoxy resins. These are the main chemical components typically found in dispersion and emulsion coatings. [0049] The specific formulation and composition may vary depending on the desired coating properties, application requirements, and industry standards. The viscosity of the coating is an important aspect when using dispersion or emulsion coatings for performance, processing, and application of the coating after die cutting is completed. The coatings used in the edge barrier viscosity can range from about few hundred to a few thousand centipoise (cP), medium-viscosity coatings typically have viscosities ranging from a few thousand to tens of thousands of centipoise (cP)T, and high-viscosity coatings having viscosities in the tens of thousands or even hundreds of thousands of centipoise (cP) range. These coatings offer a balance between flow and film build, making them suitable for various applications, including general industrial coatings, architectural paints, and certain specialty coatings. [0050] These coatings are thixotropic and may require additional mixing or dilution before application. high-viscosity coatings are commonly used in applications when gap-filling properties are desired, such as barrier coatings applied to the inconsistent and damaged blank edge fiber surface. Additionally, coatings that have a pH from about between 2 and 11 are preferably used for this barrier coating application. Other important aspects of the coating application into the edge cut area of the blank include, but not limited to polymer particles, e.g., the mean particle size of polymer particles in dispersion and emulsion coatings used in this application, including particle size ranges from submicron (less than 1 µm) to several micrometers. However, for certain specialized applications, smaller nanoparticles or larger microparticles may be utilized. Also, pigment particles can be used for cosmetic appearance and other reasons, such as inorganic pigments such as titanium dioxide having particle sizes ranging from a few hundred nanometers to micrometers. Organic pigments, on the other hand, can have smaller particle sizes, typically in the range of tens to hundreds of nanometers. Further, filler particles can have a wide range of particle sizes. Larger filler particles, such as calcium carbonate or talc, can have mean sizes ranging from several micrometers to tens of micrometers. Smaller fillers, like silica or nano-sized particles, can have mean sizes in the nanometer range. The polymer particles that can be used in the edge cut coating can include film-forming properties and contribute to the coating's adhesion, durability, and other desired characteristics. Examples of polymer particles used include acrylics, styrene- butadiene (SB) latex, polyvinyl acetate (PVA), and polyurethane, PP polypropylene, PE, polyethylene, HDPE, high density polyethylene, PVDC, PVA, acrylics, polyolefin, styrene- butadiene, polyvinyl acetate polystyrene, polyacrylates, carboxylated styrene butadiene, acrylics, polyester, or mixtures thereof in emulsion or powder form. [0051] Additionally, alcohol permeation can be reduced or halted via mechanical means during and after the paper die cutting process, this is preferably done before forming and sealing the package. Prior to die cutting, the blank paper having a planar surface coating weight range from about 10 to 30 gsm can be coated on one or both flat sides of the blank using coatings and methods previously described in the patent specification. However, alternatively, rather than coating the blank cut edge to prevent permeation, the edge of blank wall can be crosscut, and the half thickness seam folded back over from the inside to the outside of the sidewall up to about 6.35 to 12.8 mm from the cut edge of the blank. The 90-degree crosscut removes material from the blank seam such that it can folded and hemmed inside the cup. In this case, after folding and sealing, the exposed cut edge is now on the exterior of the cup instead of the inside of the cup which had previously allowed for alcohol permeation. Instead of an exposed cut edge, the round folded hemmed edge makes contact with the inside liquid and the folding action removes exposure of the inner blank cut edge from the cup liquid contents, thus preventing permeation through the blank inner cut edge. However, because of alcohol permeability, the newly exposed bent edge must be properly coated to prevent permeation on the bent inner edge of the sidewall blank. Also, in addition to using an alcohol resistant coated surface sealable using adhesives or heat seal methods. [0052] This mechanical process may be completed after a series of steps. First, during or after the die cutting process, the blank is cut with a skiving knife edge striking the blank outer surface from about a 25 degree to about at a 90-degree angle behind the liquid exposed cut edge of the sidewall blank. The knife can then crosscut at two angles and separate the inner paper walls along the seam into two overlapping pieces, of which the inner flap piece is reverse folded (see Figs. 7 and 8). When reverse folded, the now exposed uncoated blank inner paper surface is sealed, adhered using adhesive, or cold glued to outer blank surface and the coated surface of the cross cut blank is sealed or adhered using adhesive, heat seal, or using cold glue to outer blank surface to the rough uncoated surface of the inner side of the blank forming a seal zone in the heat or adhesive seal area, this seam area being sealed and having a width from about 6.35 mm to 12.8 mm. Another mechanical alternative not using a knife is possible. The blank seam can be folded and sealed such that the cut edge is now on the outside of the sidewall and not exposed to liquids, thus preventing permeation when the cut edge was located in the inner blank. For cutting operations the knife steel can be comprised of high carbon steel containing 0.6% to 1.0% carbon and having a hardness (HRC) of from about 50-70, also stainless steel can be used having approximately a 0.2% to 0.4% carbon and an approximate HRC of from 35-55, additionally Japanese steal can be used with a hardness in the approximate range of HRC 60-67. [0053] However, both mechanical processes rely on specific paper mechanical processes and specific production parameters. For example, the blank paper vertical seam that is heat or adhesive sealed would be the range of about 5.00 mm to about 10.00 mm wide, the coatings or adhesives used may have weights from about 8 gsm to about 35 gsm and paper calipers from about 300 to 700 microns, with a basis weight from about 110 gsm to 360 gsm. The paper used can be comprised from about 15% to 70% of bleached sulphate having a density from about 0.3 - 0.9 g/cm³ and from about 20% to 60% chemical thermomechanical pulp having a density in the range of about 0.3 - 0.8 g/cm³. Also, the paper can comprise from about 75% to 100% solid bleached sulphate pulp, 75-100% unbleached chemical pulps, all pulp with densities used in the structure from about 0.3 - 0.9 g/cm³. Further, the paper used preferably may have the Table 3, 4, 5 characteristics, below. Tables 3-5 do not include paper fillers or paper coatings that can be applied after the paper making machine wet end manufacturing step has been completed. Table 3, Paper Characteristic Ranges Fiber length Fiber diameter Density Strength (Tappi Moisture % 569) (ISO 287)

en ng ( ) en ng ( ) en ng L&W 15 degrees MD, mN L&W 15 degrees MD, mN L&W GM, mN

Taber Moment Taber Moment Taber Moment ZDT T-541 Bending Bending Bending

Table 4, Process Parameters, Knife Cutting, Folding, Sealing Paper Blanks Paper Feed Rate Line speed Cutting Depth Blade Length (including folding)

Blade Width Handle Length Total Knife Length Blade Thickness 430 mm 90160mm 125210 mm 04 t 12 mm

Table 5, Fiber Characteristics, Tear, Roughness, Burst Strength Fiber Weight g/m2 Tear Resistance Surface Burst Strength M R h kP

[0054] Other chemicals that could be present for the purpose of coating the exposed cut edge that is acting as seam adhesive or heat seal layer include polymers of monoolefins and diolefins, e.g., polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene, polyvinylcyclohexane, polyisoprene or polybutadiene, homogeneous mettallocene copolymers, and polymers of cycloolefins, e.g., cyclopentene or norbomene, polyethylene, cross-linked polyethylene, ethylene oxide and high density polyethylene, medium molecular weight high density polyethylene, ultra heavy weight high density polyethylene, low density polyethylene, very low density polyethylene, ultra-low density polytheylene; copolymers of monoloefins and diolefins with one another vinyl monomers, e.g., ethylene/propylene copolymers, linear low density polyethylene, and blends thereof with low density polyethylene, propylene but-1-ene, copolymers ethylene, propylene/isobutylene copolymers, ethylene/but-1-ene copolymers, ethylene/hexene copolymers, ethylene/octene copolymers, ethylene/methylepentene copolymers, ethylene/octene copolymers, ethylene/vinyelcyclohexane copolymers, ethylene/cycloolefin copolymers, COC, ethylene/I-olefin copolymers, the 1-olefin being produced in situ; propylene/butadiene copolymers, isobutylene/isoprene copolymers, ethylene/vinylcyclohexene copolymers, ethylene vinyl acetate copolymers, ethylene/alkyl methacrylate copolymers, ethylene/acrylic acid copolymers or ethyelene/acrylic acid copolymers and salts thereof (ionomers) and terapolymers of ethylene with propylene and diene, such as, for example, hexadiene, polytetrafluoroethylene (PTFE) or fluorinated ethylene propylene dicyclopentadiene or ethylidenenorbomene, pvdc, homopolymers and copolymers that may have any desired three dimensional structure (stereo-structure), such as, for example, syndiotactic, isotactic, bioPBS, hemiisotactic or atactic stereoblock polymers are also possible; polystyrene, poly methylstyrene, poly alph-methystyrene, aromatic homopolymers and copolymers derived from vinylaromatic monomers, including styrene, alpha-methylstyrene, all isomers of vinyltoluene, in particular p-vinyletoluene, all isomers of ethylstyrene, propylstyrene, vinylbiphenyl, vinylnaphthalene and blends thereof, homopolymers and copolymers of may have any desired three dimensional structure, including syndiotactic, isotatic, hemiisotactic or atactic, stereoblock polymers; copolymer, including the above mentioned vinylaromatic monomers and commoners selected from ethylene, propylene, dienes, nitriles, acids, maleic anhydrides, vinyl acetates and vinyl chlorides or acryloyl derivatives and mixtures thereof, for example styren/butadiene, styrene/acrylonitrile, styrene/ethylene (interpolymers) styrene/alkymethacrylate, styrene/butadiene/alkyl acrylate, styrene/butadiene/alkyl methacrylate, styrene/maleic anhydride, styrene copolymers; hydrogen saturated aromatic polymers derived from by saturation of said polymers, including polycyclohexylethylene; polymers derived from alpha, beta- unsaturated acids and derivatives; unstaturated monomers such as acrylonitrile/butadiene copolymers acrylate copolymers, halide copolymers and amines from acyl derivatives or acetals; copolymers with olefins, fluoropolymers, homopolymers and copolymers of cyclic ethers; polyamides and copolyamides derived from diamines and dicarboxylic acids and or from aminocarboxylicacides and coITesponding lactams; polyesters and polyesters derived from dicarboxylic acids and diols and from hydroxycarboxylic acids or the coITesponding lactones; blocked copolyetheresters derived from hydroxyl terminated polyethers; polyketones, polysulfones, polyethersufones, and polyetherketones; cross-linked polymers derived from aldehydes on the one hand phenols, ureas, and melamines such as phenol/formaldehyde resins and cross-linked acrylic resnes derived from substantial acrylates, e.g., epoxyacrylates, urethaneacrylates or polyesteracrylates and starch; polymers and copolymers of such materials as poly lactic acids and its copolymers, cellulose, polyhdyroxy alcanoates, polycaprolactone, polybutylene succinate, polymers and copolymers of N-vinylpyrroolidone such as polyvinylpyrrrolidone, and corsslinked polyvinylpyrrolidone, ethyl vinyl alcohol. More examples of thermoplastic polymers suitable for the mineral- containing composite include polypropylene, high density polyethylene combined with MS0825 Nanoreinforced POSS polypropylene, thermoplastic elastomers, thermoplastic vulcinates, polyvinylchloride, polylactic acid, virgin and recycled polyesters, cellulosics, polyamides, polycarbonate, polybutylene tereaphthylate, polyester elastomers,thermoplastic polyurethane, cyclic olefin copolymer; biodegradable polymers such as Cereplast-Polylactic acid, Purac-Lactide PLA, Nee Corp PLA, Mitsubishi Chemical Corp GS PLS resins, Natureworks LLC PLA, Cereplast-Biopropropylene, Spartech PLA Rejuven 8, resins made from starch, cellulose, polyhydroxy alcanoates, polycaprolactone, polybutylene succinate or combinations thereof, such as Ecoflex FBX 7011 and Ecovio L Resins from BASF, polyvinylchloride and recycled and reclaimed polyester such as Nodax biodegradable polyester by P & G. [0055] Alcohol and alcohol mixed with other liquids can be rapidly absorbed by fibers and therefore the permeation quickly discolors and degrades the appearance and cosmetics of the packaging structure and negatively effects the structural integrity of the package. The type of alcohol, such as methanol, ethanol, isopropanol, or higher alcohols, may have different permeation rates due to variations in their molecular size, polarity, and interactions with paper fibers. The composition of the paper, including the type of fibers and any additives or coatings present, can influence alcohol permeation rates. Papers with more porous structures or higher cellulose content tend to have higher permeation rates. Paper thickness, thicker papers typically have a higher permeation capacity, allowing for a greater amount of alcohol to be absorbed. However, the rate of permeation may still be influenced by factors such as the porosity and surface area of the paper. Temperature, humidity, and air circulation can affect the rate of alcohol permeation into paper. Higher temperatures and lower humidity levels generally enhance the permeation process due to increased molecular mobility and evaporation of solvents. One purpose of the invention is to reduce permeation of alcohols in the density range of about .77 g/cm3 to about .82 g/cm3. The invention is designed to reduce alcohol permeation when coating the inner blank wall cut edge into packaging structures containing fibers having the attributes illustrated in Table 6, below. Table 6, fiber characteristics Filled Fiber Content 1% to 30%

[0056] When applying the multi axial coatings, which include the flat planar surfaced and the cut edges of the blank, the package cut blanks can comprise multiple paper layers and have cut edges for each layer, each layer possibly exposed to liquids and therefore requiring multi axial protective coatings on the preformed packaging blanks, e.g., on the cut edges and also the flat. The coatings applied to the planar surfaces of the blank facing approximately 90 degrees from the cut edge with actual knife cut angle from about 30 degrees to 140 degrees. The package blanks can weigh from about 129 lbs/msf to about 173 lbs/3msf and have a thickness from about .010” to about .026”. The package blank surface having a TAPPI Brightness (TAPPI T 452) of a range of 75-100, and for bagasse papers a Tappi Brightness from about 25 to 75. Also, the paper cut blanks having a consistent brightness and strength with no discoloration or reduced tear strengths due to alcohol permeation wetness. [0057] EXAMPLE [0058] In this example, a customer requested a more environmental alternative to 100% thermoformed plastic cups. Therefore, paper packaging was preferred. However, due to alcohol permeation, previously available paper cups failed to provide an acceptable barrier solution. Therefore, seeking a paper cup having alcohol and liquid barrier, a representative sampling of various cup packaging blanks were prepared. The paper fibers in the cup samplings had properties found within Table 3. Also, the paper blanks with a Tappi Brightness of from 79 to 95, a CIE whiteness of from 65 to 95, a fiber density of between .3 to .7 g/cml, and Elmendorf tear strength of from 5-25 mN, the blank paper weights from 129 lbs/msf to about 273 lbs/ msf with calipers from .010” to .026” and fiber moisture content from 2% to 8%. Prior to cutting the blanks, the parent paper roll was polyolefin extrusion coated. The extrusion coatings applied to one or two sides of the planar surfaces of the blanks in the coat weight range of about 10 gsm to about 28 gsm. The extrusion coatings included some having by weight up to 45% diatomaceous filler content. The blank samples edges were cut to shape at 90 degrees from the outer facing sides of the blank planar surfaces. The cut blank edges comprising circular, straight, straight with radius sections, and combinations thereof. Next, an acrylic containing dispersion coating was prepared having a PH within a range of about 2 to 11, a viscosity from about 150 to 250 cps, a coating particle molecular weight greater than 100,000, a TG in the range of 55 to 75 C, and post application density at 25 C from about .95 to about 1.15 g/cm3. The dispersion coating was then applied to the exposed cut blank edges in weight ranges from about 3 to 20 gsm, with the coating seeping into the cut edge fibers from 10 to 80 microns for the outer edge of the cut blank, thus providing permeation protection inside the fiber structure of the blank. Upon completion of the coating process, the blanks have a multi axial coating coverage. For example, axis one being the outer facing flat planar surface, axis two being the outer facing exposed edge of the cut blank, and the third axis having coating coverage along the varying cut edge angles formed through circular, straight, and radius edges of the blank cuts, or combination thereof. Adhesion and curing of the above coatings is preferably completed prior to the next step. [0059] Next, to enhance cross linking density and therefore improve permeation barrier to alcohol, the coating was cured a second time along the outer blank edge areas. This second curing step applied heat and pressure to the cut edge surface area up to 410 F, with pressures up to 2.5 mPA up to 0.5” from the outer exposed cut edges. The heat and pressure applied simultaneously in time durations up to 4.25 seconds. The secondary heat and pressure compressing and rapid curing the edge of the blank, improving cross-linking density across the linear outer edge and three dimensionally across the entire surface of the blank edge. The minimum finished cross linking densities found in the edge cut area were from about 10^4 to 10^6 cross-links per nm3 to approximately 10^6 to 10^8 cross-links per nm3. Upon completion of the secondary curing process, at room temperature, the packages were then exposed to a range of 88 mL liquid solutions containing from 15% to 55% by volume of alcohol, the alcohol having a density in the range of .77 to .82 g/ml. The paper with a Tappi Brightness of from 70 to 95, a CIE whiteness of from 65 to 95, a fiber density of between .3 to .7 g/cml, and Elmendorf tear strength of from 5-25 mN, and a fiber moisture content from 2% to 18%. The liquid permeation in the cup was observed at 15 minutes, 30 minutes, 1 hour, 2 hours, and 12-hour time frames. Observations included the exterior and interior of the package on both the outermost coated areas and the outer facing fiber surface adhesion to the coating. The permeation rate of degradation and failure criteria was determined upon the total overall average surface area on the inner side of the planar surface and along the perimeter of the cut edges of the tested samples. Terminal failure identified at 5% overall average discoloration of the inner package surface, a 5% overall reduction in surface brightness, a 5% or more reduction in whiteness, and a 5% tear strength reduction. Example 1 sampling results and averages across the surface area of the samples are illustrated in Table 7, below. Table 7, Example 1, ranges of permeation degradation rates, inner surface area Time Brightness Whiteness Tear Discoloration

2 hours fail-100% fail-99% 95-100% >11% 12 hours fail-98% fail-99% fail-100% >16%

Time % Permeation Permeation mL 15 minutes 0-4 0-352 of

[0061] Regarding the Figures, Fig.1 is an illustration of a top view of a rectangular blank showing from outer planar coated surface 1 bound directly to the fiber layer 2 by polyolefin extrusion coating. Fig.1 illustrates four cut edges around the outer perimeter of the blank. Fig.1 shows the possibility of triaxial coating on several different surfaces, e.g., four cut edges and top coated surface 1. [0062] Fig.2 is an illustration of a perspective view of a blank with both straight and radius edges having three layers. Fig. 2 shows the blank with both straight and radius edges having three layers, layer 3 is an outer coated surface comprising dispersion or aqueous coatings, fiber layer 4, which is directly bound by a shared interfacial bonding surface. Directly bound to the bottom of fiber layer 4 is a second coated surface 5, which can be comprised of extrusion, dispersion, or emulsion coatings. Fig. 2 illustrates multi axial coatings, for example, four layers of coating on the four cut edges of the blank, the top planar surface of the blank and the bottom planar surface of the blank. Also, the four cut edges of the blank in this area were post curing heat and pressure is applied up to 0.5 inches inside the cut edge and coating seeping from 3 to 80 microns to improve cross linking density and improve permeation resistance of alcohol. [0063] Fig.3 is an illustration of a top perspective view of an irregularly shaped blank having one top fiber layer planar surface 6 bound to a top coating layer and one bottom fiber planar surface 7. Fig. 3 illustrates multi-axial coating surfaces, comprised of two flat outward facing planar surfaces, and connected but individually shaped and not in a flat plane, outer cut edges. When applied, the cut edge coatings seeping from 3 to 80 microns horizontally into the fibers. Also, it is this area up to 5” from the cut edge, the secondary curing heat and pressure is added to improve cross linking density and improve permeation resistance of alcohol and improved adhesion. [0064] Fig. 4 is an illustration of a cross-section view of the embodiment shown in Fig. 1 of an example blank side view showing a flat planar outer facing coating layer 1 bound along the interfacial surface of outer facing fiber layer 2. Fig.4 shows flat planar outer facing coating layer 1 and fiber surface 2 that is an example of a cut edge surface that is also shown in Figs.1, 2, 3, and 5, and, when coated, the coating seeping from 3 to 80 microns horizontally into the fiber layer(s). Also, it is this area the post curing heat and pressure is applied to the facing edge 2 then up to 5” from the outer edge 2 into to improve cross linking density and improve permeation resistance of alcohol and improved adhesion. [0065] Fig.5 is an illustration of a top front perspective view of a square shaped cut blank having one coating layer and one fiber layer. Fig.5 shows one embodiment of a square blank 100 having four different edge cut surfaces 10, 11,12, 13, available for triaxial coatings, and shows one layer of coating on each side of the blank. [0066] Fig.6 is an illustration of a perspective view of an example showing a section of the seam area after the skiving knife has cut and separated the seam in preparation for folding and sealing. Fig.6 shows one embodiment of a section of the seam area of blank 600 after the skiving knife has cut and separated the seam in preparation for folding and sealing. The outer blank paper surface 605 represents the inner side of the cup blank that is coating with a selection of identified chemicals found this specification and once folded along the axis of score line 603, the paper surface 604 is heat or adhesive sealed to blank paper surface 602. In order to bond and sealing with paper surface 602, paper surface 604 is coated with chemicals previously described for that purpose within this specification. Seam edge 607 illustrated the opposite side from seam edge 603 and after folding, the line edge between 603 and 607 form the new interior package seam edge making contact with the liquid in the package, eliminating the cut edge and reducing alcohol permeation inside the package. 601 and 606 represent the continuing edge of the package lip are such that after hemming their 360-degree area around the package does not make contact with liquids. [0067] Fig.7 is an illustration of a front view of the inside of the post sealed package wall blank seam area. Fig.7 shows blank 700 may be folded in on itself to create a package, such as a cup. Fig. 7 shows and V indicates the crosscut and folded sections 704, 708, which may be adhesively, heat sealed, or otherwise bonded together, and hemmed into a continuous vertical seem from about 6.35mm to 7.8 mm width. Fig. 7 also shows that section 704 is the cut and folded over portion of coated surface 702, which may then be bonded with surface 708. Surface 706 may be a coated or uncoated outer planar surface of blank 700. Coated surface 702 may be the inner opposite planar surface of the blank and coated with adhesive or heat coatings such that surface 708 and surface 704 are bonded into a vertical seam. [0068] Fig. 8 is an illustration of a top view of a reverse folded sidewall package blank. Fig. 8 shows that package blank 800 has an inner area 802 of the formed package containing a volume of liquid or solid product. Surface 804 is the inner planar surface of the coated blank 800 after forming the package. The blank 800 may also include coated outer planar surface 806 and cut edge 808, which, after reverse folding, will be on the outside of the package vertical seam, such that it is not exposed to internal liquid permeation. As shown, blank 800 may have surface 810, which may be the outer coated blank planar surface location after the reverse fold. Preferably, surface 810 may be adhesive or heat sealed to the inner coated surface 804. Fig. 8 also shows that the blank 800 may have coated outer blank surface 812, which, after reverse folding, may be sealed by a finished vertical seal to surface 804 and 810. Fig. 8 also shows edge 814 (which may be referred to alternatively as a reverse fold or bend line), which may replace the cut edge on the inside of the cup formed from blank 800. Because there are no exposed fibers, edge 814 prevents alcohol permeation on the inside seam of the package. [0069] Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, locations, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain. [0070] The foregoing description of the preferred embodiment has been presented for the purposes of illustration and description. While multiple embodiments are disclosed, still other embodiments will become apparent to those skilled in the art from the above detailed description. These embodiments are capable of modifications in various obvious aspects, all without departing from the spirit and scope of protection. Accordingly, the detailed description is to be regarded as illustrative in nature and not restrictive. Also, although not explicitly recited, one or more embodiments may be practiced in combination or conjunction with one another. Furthermore, the reference or non-reference to a particular embodiment shall not be interpreted to limit the scope of protection. It is intended that the scope of protection not be limited by this detailed description, but by the claims and the equivalents to the claims that are appended hereto. [0071] Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent, to the public, regardless of whether it is or is not recited in the claims.

Claims

CLAIMS What is claimed is: 1. A method for preparing coated packaging blanks comprising the steps of: a. providing a paper sheet or paper roll, wherein said paper comprises cellulose fibers; b. coating said paper sheet or paper roll on at least one of the opposing planar top and bottom surfaces with at least one layer of a polymer-containing coating; c. optionally performing a curing and/or drying step; d. cutting the coated paper sheet or coated paper roll to provide the desired geometrical form and size of the coated packaging blanks; e. applying at least one layer of a dispersion or emulsion coating on at least one of the side edges (each side edge/side surface has a (significantly) smaller surface area compared with the opposing planar top and bottom surfaces, which are the main surfaces) of said packaging blanks, and f. optionally performing a curing and/or drying step.

2. The method of item 1, wherein the coating step(s) comprise at least one method selected from the group consisting of extrusion coating, extrusion lamination, dispersion coating, and emulsion coating.

3. The method of claims 1 or 2, wherein the dispersion coating methods and emulsion methods are selected from the group consisting of blade coating, air knife coating, roll coating, size press coating, curtain coating.

4. The method according to any preceding claim, wherein the polymer-containing coating is a coating comprising, consisting of, or consisting essentially of polyolefin; such as polyethylene or polypropylene; polyester, and/or vinyl alcohol.

5. The method according to any preceding claim, wherein the dispersion or emulsion coating is an acrylic or acrylic-latex dispersion or emulsion coating, such as a coating comprising, consisting of, or consisting essentially of one or more polymers selected from the group 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, methyl methacrylate co-polymer; preferably all (side) edges are provided with said dispersion or emulsion coatings, thereby providing packaging blanks which are fully coated by either the polymer-containing coating of step (a) or the dispersion or emulsion coatings of step e), preferably, the first coating step with polymer- containing coating provides a coating on the planar/flat opposing planar top and bottom surfaces (i.e. the outer facing surfaces of the blank).

6. The method according to any preceding claim, wherein the curing of the polymer- containing coating on the planar/flat opposing planar top and bottom surfaces is completed before the next coating step, which is preferably, the coating of the side edges, which further coating step is preferably completed by applying heat and pressure.

7. The method according to any preceding claim, wherein the step of cutting the coated paper sheet or coated paper roll provides a cutting (side) edge which has an angle of about 30 to about 140 degrees with respect to one of said opposing planar top and bottom surfaces, preferably wherein the angle is between 80 and 110 degrees, preferably approximately 9- degrees, or is between 30 and 80 degrees.

8. The method according to any preceding claim, wherein the step of cutting the coated paper sheet or coated paper roll provides one or more cutting (side) edges having a shape selected from the group consisting of a circular, a straight, a radius edge, and combinations thereof.

9. The method according to any preceding claim, wherein after applying and curing the coating(s) on at least one of the (side) edges/surfaces, post-curing heat and pressure is applied to the (side) edge trim area, preferably thereby achieving cross-linking of one or more of said coating(s).

10. The method according to any preceding claim, wherein after cutting the (side) edges have exposed fibers that are unprotected from alcohol permeation.

11. The method according to any preceding claim, wherein the curing of the coating on at least one of the (side) edges /surfaces is performed by applying heat and pressure to the (side) edge trim area, preferably thereby achieving cross-linking of one or more of said coating(s), wherein the degree of finished cross-linking in the edge cut area/coating(s) on at least one of the (side) edges/surfaces is from about 104 cross-links per nm3 to approximately 106 to 108 cross- links per nm3, preferably from 106 to 108 cross-links per nm3.

12. The method according to any preceding claim, wherein the step of applying acrylic- or acrylic-latex dispersion or emulsion coatings on at least one of the (side) edges/side surfaces of said packaging blanks is done during the process of blank stacking, moving, or transporting to the package forming and converting station.

13. The method according to any preceding claim, wherein the polymer-containing coating(s) is/are applied with weights from 10 gsm to 40 gsm, such as 10 to 30 gsm (considering the total amount of all coatings on the coated packaging blanks), and/or wherein the polymer-containing coating on at least one of the opposing planar top and bottom surfaces is not an acrylic or acrylic- latex coating, and/or wherein one or more of the polymer-containing coating(s) on at least one of the opposing planar top and bottom surfaces has a mineral content and/or wherein the coating(s) on the (side) edges/surfaces do not contain minerals.

14. The method according to any preceding claim, wherein the coatings on the (side) edges/side surfaces, in particular the acrylic or acrylic-latex coating(s), is/are applied with weights from 3 gsm to 20 gsm (total weight of all coatings or weight of individual coating layers).

15. The method according to any preceding claim, wherein one or more of the coatings impregnate into the cellulose fibers at one or more positions to be present at about 3 to 80 microns from the nearest edge, preferably creating edge horizontal as well as vertical permeation resistance.

16. The method according to any preceding claim, wherein the two opposing planar top and bottom surfaces together with all side edges/side surfaces form the whole surface of the coated packaging blanks.

17. The method according to any preceding claim, wherein a drying and curing station is located after the coating material is applied to the fiber, wherein curing temperatures are between 100°C (212°F) to 200°C (392°F) in hot air ovens, drying sections, or drying tunnels.

18. The method according to any preceding claim, wherein the polymer- and mineral- containing coating, has a mineral content of between 1 and 50 wt.%, or between 1 and 30 wt.% based on the total paper weight.

19. The method according to any preceding claim, wherein the cellulosic fibers comprise fibers having a diameter/width of 16-42 microns, preferably as measured according to TAPPI T271 OM-15: “Fiber Analysis of Paper and Paperboard” and also TAPPI T233 OM-15: “Fiber Length of Pulp and Paper by Automatic Image Analysis.

20. The method according to any preceding claim, wherein one or more of the polymer- containing coating(s) and/or one or more of dispersion or emulsion coatings comprises one or more components selected from binders, pigments, dispersing agents, thickeners or rheology modifiers, coalescing agents, surfactants and crosslinkers.

21. The method according to any preceding claim, wherein the thickness of the paper blanks, i.e. the distance of the opposing flat surfaces thereof is between about 0.010” to about 0.026” and/or weigh from about 129 lbs/msf to about 273 lbs/3msf, preferably 129 lbs/msf to about 173 lbs/3msf.

22. The method according to any preceding claim, wherein the thickness of the paper blanks corresponds to the length of the shorter side (cut) edge if a 90° cut or no cut has been made to obtain said edge, but the thickness of the paper blanks is shorter than the length of the shorter side cut edge if a degree other than 90° is used for cutting.

23. The method according to any preceding claim, wherein the paper blanks correspond to the length of the shorter side (cut) edge if a 90° cut or no cut has been made to obtain said edge, but the thickness of the paper blanks is shorter than the length of the shorter side cut edge if a degree other than 90° is used for cutting.

24. The coated packaging blanks according to the previous claim, obtainable or obtained by the process of the invention, preferably a process as described in any of claims 1-23.

25. Packaging structure comprising at least one, preferably at least two or two, coated packaging blank(s) of claim 24.

26. The packaging structure of claim 26, assembled by heat sealing together at least two coated packaging blanks of any of claims 24 or 25.

27. A method for preparing coated packaging blanks comprising the steps of: a) providing a paper sheet or paper roll, wherein said paper comprises cellulose fibers, b) coating said paper sheet or paper roll on at least one of the opposing planar top and bottom surfaces with at least one layer of a polymer-containing coating, c) optionally performing a curing and/or drying step, d) cutting the coated paper sheet or coated paper roll to provide the desired geometrical form and size of the coated packaging blanks, e) applying at least one layer of a dispersion or emulsion coating on at least one of the side edges (each side edge/side surface has a (significantly) smaller surface area compared with the opposing planar top and bottom surfaces, which are the main surfaces) of said packaging blanks, and f) optionally performing a curing and/or drying step.

28. The method of Claim 27, wherein the coating step(s) comprise at least one method selected from the group consisting of extrusion coating, extrusion lamination, dispersion coating, and emulsion coating.

29. The method of Claim 27 or 28, wherein the dispersion coating methods and emulsion methods are selected from the group consisting of blade coating, air knife coating, roll coating, size press coating, curtain coating.

30. The method according to any preceding claim, wherein the polymer-containing coating is a coating comprising, consisting of, or consisting essentially of polyolefin and biopolymers; such as polyethylene or polypropylene; polyester, and/or vinyl alcohol, polylactic acid, and bioPBS.

31. The method according to any preceding claim, wherein the steps of cutting the coated paper blank, sheet or paper roll provides a cutting (side) edge which and of which is folded to prevent exposure of the cut edge of the blank to the internal contents of the package thus reducing inner permeation into the sidewall blank.

32. The packaging structure according to claim 28, which forms an open or closed container for containing a liquid, where no non-coated surfaces and no non-coated edges can come into contact with a liquid in filled state; wherein, the sidewall blank fibers having lengths in the range of about of .5mm to 6 mm, fiber diameters from a range of 10 microns to 40 microns, paper densities from about 225 kg/m3 to about 675 kg/m3.

33. The packaging structure according to claim 28, which forms an open or closed container for containing a liquid, where no non-coated surfaces and no non-coated edges can come into contact with a liquid in filled state; comprising from about 75% to 100% solid bleached sulphate pulp, 75-100% unbleached chemical pulps, all pulps with densities used in the structure from about 0.3 - 0.9 g/cm³; wherein, the sidewall blank having an ISO 2493 MD Bending L & W, 15 degrees MD, mNm, in the range of 247 to 1320, and having an ISO 2493 CD Bending L &W 15 degrees MD, mN, in the range of 94 to 510 and also having a Bending L & W, GM mN in the range of 152 to 811 and the sidewall blank having a Taber Movement Bending 15 degrees MD, mNm in the range of 10 to 64 degrees, a Taber Moment Bending 15 degrees CD mNm in the range of 4.5 to 30 degrees, a Taber Moment Bending GM, mNm in the range of 6.0 to 44 and a T-541 ZDT kPa range from 310 to 259.

34. The packaging structure, according to claim 28, wherein, the knife and paper blade having a feed rate of from 10 meters to 160 meters per minute, a line speed including folding of 10 meters to 205 meters per minute, a cutting depth of from .3mm to .9 mm, blade length from 25 mm to 70 mm, blade width from 4 mm to 30 mm, handle length 90 mm to 160 mm, a total knife length of 125 mm to 210 mm and blade thickness from .4 to 1.2 mm.

35. The packaging blank, according to claim 28, the paper used can be comprised from about 15% to 70% of bleached sulphate having a density from about 0.3 - 0.9g/cm³ and from about 20% to 60% chemical thermomechanical pulp having a density in the range of about 0.3 - 0.8 g/cm³.