Ductile metallic foil sheet having hexagonal embossing elements for improved performance properties

Abstract

A metallic foil sheet, comprising a plurality of embossing elements provided on at least one surface of the sheet, wherein all or a majority of the plurality of the embossed elements comprise at least three linear segments that are positioned in a parallel, intersecting, or concentric layout relative to each other on a hexagonal grid or tiling to form a two-dimensional hexagonal close-packed array or tessellation.

Description

DUCTILE METALLIC FOIL SHEET HAVING HEXAGONAL EMBOSSING ELEMENTS FOR IMPROVED PERFORMANCE PROPERTIESField

[0001] The present disclosure generally relates to ductile metallic foils and, more particularly, to foil-specific improvements in performance properties derived from hexagonal embossing geometry.Background

[0002] The performance of embossed metallic foils, such as embossed aluminium foils for cooking and / or household applications, is a complex result of mechanical, functional and aesthetic properties including strength, tear resistance, puncture resistance, elasticity, stretchability, formability, ductility, heat conductivity, dead-foldability, liquid dispersion, aesthetic appearance, and geometry of embossing shapes and patterns.

[0003] These performance properties are also further influenced by important design-for-manufacture considerations including gauge or thickness of metallic foil, cost and grade of metallic foil, choice, cost, life and complexity of embossing dies, ease and speed of manufacture, direction, angle and complexity of embossing, depth and spacing of embossing, and strain hardening from embossing. For example, existing embossed aluminium foils are commonly formed by rolling aluminium foil between a metal embossing roller and a rubber embossing roller each cut with the desired embossing pattern. The rubber embossing roller is prone to wear and produces a weak embossing pattern in the embossed aluminium foil that is typically is not perceptible tactilely, and barely or faintly perceptible visually.

[0004] Existing embossed metallic foils for applications such as cooking suffer several shortcomings. For example, embossing generally increases strength but typically reduces tear resistance. Thin, low grade metallic foils with simple embossing patterns are cheap and easy to manufacture but typically have reduced stretchability and reduced resistance to punctures and tear propagation.

[0005] In order to address these problems, the present applicant previously developed a unique embossed metal foil described in US 8911877, the contents of which is hereby incorporated by reference in its entirety, having a regular repeating embossing pattern of a plurality of discrete S-shaped ribs spaced apart from and parallel to one another, wherein areas around the ribs form a plurality of channels that intersect one another to tortuous paths for fluids. By including the claimed S-shaped pattern, the embossed metal foil has an improved cooking performance. For example, the S-shaped rib pattern omnidirectionally controls the dispersion of fluids in the plane of foil, thereby avoiding pooling and runoff of the cooking fluid. In addition, the plurality of channels formed by the claimed S-shaped pattern increase the contact area of the food during cooking. The repeating S-shaped embossing pattern also has an increased rigidity and dimensional stability as compared with conventional smooth metal foils and prior art patterned foils. The resulting embossed metal foil has improved cooking benefits that enable tastier, healthier, cleaner, faster, and more convenient cooking of foods with less oil and fat. The S-shaped embossing pattern is, however, difficult to manufacture due to the complex shape of the S-shaped ribs.

[0006] In view of this background, there is an unmet need for embossed metallic foils having an improved combination, or better balance, of mechanical, functional, and aesthetic properties.Summary

[0007] According to the present disclosure, there is provided a flexible, ductile metallic foil sheet, comprising:a plurality of embossing elements provided on at least one surface of the sheet; wherein all or a majority of the plurality of the embossed elements comprise at least three linear segments that are positioned in a parallel, intersecting, or concentric layout relative to each other on a hexagonal grid or tiling to form a two-dimensional hexagonal close-packed array or tessellation.

[0008] All or a majority of the plurality of embossed elements may comprise at least two concentric hexagons that are closed or partially open on a plurality of adjacent sides.

[0009] In one example, all or the majority of the plurality of embossed elements may comprise a repeating pattern of a plurality of concentric hexagons each having two adjacent sides left open to form a plurality of concentric hexagonal arches.

[0010] In another example, all or the majority of the plurality of embossed elements may comprise a repeating pattern of three concentric hexagons comprising outer, middle and inner hexagons, wherein the outer hexagon is defined by three linear segments arranged to form three parallel zig-zag lines, and wherein the inner hexagon comprises a solid two-dimensional hexagon.

[0011] In a further example, all or the majority of the embossed elements may comprise a repeating pattern of a plurality of concentric hexagons, wherein a plurality of linear segments are arranged spaced apart in parallel inside an innermost concentric hexagon.

[0012] The plurality of embossed elements may be separated by a plurality of less embossed or unembossed areas of the metallic foil. The less embossed or unembossed areas form a continuous network surrounding the plurality of embossed elements.

[0013] The plurality of less-embossed areas may be micro-embossed to have a contrasting visual appearance relative to the plurality of embossed elements. The microembossed areas may have a frosted or satin visual appearance. The plurality of embossed elements may have a glossy or shiny visual appearance.

[0014] A non-stick coating, such as a silicon non-stick coating, may be provided on one or both of the plurality of embossed elements and the plurality of less embossed or unembossed areas. The non-stick coating may be provided on one or both sides of the metallic foil.

[0015] The metallic foil may comprise a shiny side and a dull side, wherein the plurality of embossed elements are embossed in the shiny side.

[0016] The plurality of embossed elements may have a height and / or depth between 0.05 mm and 1 mm, for example, between 0.1 mm and 0.5 mm.

[0017] The plurality of embossed elements may have a width of between 0.05 mm and 5 mm.

[0018] The plurality of embossed elements may be spaced apart from each other by between 1 mm and 3 mm. The plurality of embossed elements may be perceptible visually and tactilely on one or both sides of the metallic foil.

[0019] The metallic foil may have a thickness between 0.010 mm and 0.20 mm.

[0020] The metallic foil may comprise 8011 or 8006 aluminium alloy.

[0021] The present disclosure also provides a metallic product made from or comprising the metallic foil described above.

[0022] The metallic product may comprise a foil sheet, a foil roll, a foil roll dispenser, a receptacle, a tray, a container, a lid, cookware, bakeware, a food package, and combinations thereof.

[0023] The present disclosure also provides an embossed metallic foil, comprising a plurality of embossed elements separated by a plurality of less-embossed areas, wherein the plurality of embossed elements have a shiny visual appearance, wherein the plurality of less-embossed areas have a frosted or satin visual appearance, and wherein a nonstick coating is provided on one or both sides of the embossed metallic foil.

[0024] The embossed metallic described above may be formed by rolling metallic foil between two metal embossing rollers.Brief Description of Drawings

[0025] Non-limiting and non-exhaustive examples are described with reference to the following figures:Figure 1 is an example of an “all-purpose” or “standard-duty” embossed metallic foil (Example 1);Figure 2 is an example of a “heavy duty” embossed metallic foil (Example 2); andFigure 3 is an example of a “non-stick” embossed metallic foil (Example 3).Detailed Description

[0026] Referring to the drawings, examples of ductile metallic foils 10, 20, 30 according to embodiments of the present disclosure may generally comprise a plurality of elevated and / or depressed embossed elements 12, 22, 32 that are provided on at least one surface or side of metallic foil sheets or substrates 10, 20, 30. In some examples, all or a majority of the plurality of the embossed elements 12, 22, 32 may comprise at least three linear segments that are positioned in a parallel, intersecting or concentric layout relative to each other on a hexagonal grid or tiling to form a two-dimensional hexagonal close-packed array or tessellation.

[0027] In some examples, the majority of the plurality of embossed elements 12, 22, 32 may comprise a plurality of concentric hexagons that are closed or partially open on a plurality of adjacent sides. In one example shown in Figure 1, all or the majority of the embossed elements 12 may comprise a repeating pattern of a plurality of concentric hexagons 12a, 12b, 12c, wherein a plurality of linear segments 12d are arranged in parallel inside an innermost concentric hexagon 12c. In some examples, the plurality of embossed elements 12, 22, 32 may comprise a nested configuration of hexagonal cells that define structural reinforcement zones across the substrate. In some examples, the plurality of embossed elements 12, 22, 32 may be configured to redirect tear propagation forces, resulting in an increase in tear resistance compared to the foil sheet or substrate in an unembossed state.

[0028] In another example shown in Figure 2, the majority of the plurality of embossed elements 22 may comprise a repeating pattern of three concentric hexagons comprising outer, middle and inner hexagons 22a, 22b, 22c. The outer hexagon 22a may be defined by three linear segments arranged to form three parallel zig-zag lines 22d, 22e, 22f, and the inner hexagon 22c may comprise a solid two-dimensional hexagon.

[0029] In a further example shown in Figure 3, the majority of the plurality of embossed elements 32 may comprise a repeating pattern of a plurality of concentric hexagons 32a,32b, 32c, 32d each having two adjacent side left open to form a plurality of concentric hexagonal arches.

[0030] In some examples, the plurality of embossed elements 12, 22, 32 may be separated by a plurality of less embossed or unembossed areas of the metallic foil. The plurality of less-embossed areas may have a contrasting visual appearance, such as a contrasting matt or gloss appearance, relative to the plurality of embossed elements 12, 22, 32. In some examples, the plurality of less-embossed areas may be micro-embossed to have a contrasting matt appearance relative to the plurality of embossed elements 12, 22, 32. The micro-embossed areas may, for example, have a frosted or satin visual appearance. The plurality of embossed elements may, for example, have a shiny visual appearance. In some examples, the metallic foil may comprise a shiny side and a dull side, wherein the plurality of embossed elements are embossed in the shiny side. As used herein, "glossy" and "shiny" refer to surface finishes having a specific surface roughness (Ra) lower than that of the "frosted" or "satin" areas. In some examples, the plurality of embossed elements 12, 22, 32 may include a secondary micro-embossing within the primary hexagonal cells to enhance surface grip and thermal distribution.

[0031] In some examples, one or more of the depth, size, shape, emboss roll pressure, and orientation of the micro-embossing of the micro-embossed areas may be selectively controlled to have positive effects on one or more functional and / or aesthetic properties of the embossed metallic foils 10, 20, 30, such as visual appearance, strength, thinning of material, work or strain hardening, stress concentrations, etc.

[0032] In some examples, the depth of the micro-embossing of the micro-embossed areas may have a depth between 10 and 30 pm. This shallow micro-embossing may avoid or minimise the risk of weakening the embossed metallic foils 10, 20, 30 such that the metallic foil material is not significantly thinned. The micro-embossed areas may have different gloss levels that are provided with micro-embossings or a microstructure having a maximum depth of 30 pm. The greater the depth of the microstructure, the more the micro-embossed areas may have a matt texture or appearance. The lesser the depth of the microstructure, the more the micro-embossed areas may have a glossy appearance. The depth of the micro-embossing may vary over the surface of the embossed metallic foils 10, 20, 30 such that varying gloss levels are obtained.

[0033] In some examples, one or both of the shape and size of the micro-embossed areas may be selectively controlled to have positive effects on the mechanical properties of the embossed metallic foils 10, 20, 30, such as stiffness, strength, and resistance to deformation, by leveraging geometric principles. The hexagonal grid provides an isotropic mechanical response in the plane of the foil, allowing the sheet to deform uniformly in response to multi-axial strain. For example, the pattern of the micro-embossing may have a geometric shape, such as closed or partially open polygons, that is selected to provide geometric reinforcement to create a three-dimensional structure that increase the foil’s stiffness, rigidity, or resistance to bending. In some examples, the shape of the microembossing may comprise a grid of squares, hexagons, or honeycomb shapes, or a corrugated or ribbed pattern, that enhances stiffness without adding extra material. Further or alternatively, the micro-embossing pattern may comprise honeycombs or hexagonal grids that distribute applied loads more evenly across the surface, reducing stress concentrations and preventing localised deformation. The raised or recessed shapes and patterns created by micro-embossing may act to relieve stress making the foil less susceptible to tearing and puncturing.

[0034] Further or alternatively, the micro-embossing areas may have raised or recessed shapes or geometric features that act as structural supports, making the foil more resistant to buckling or crumpling under compression. The shape and size of the features or pattern of the micro-embossing areas of the embossed metallic foils 10, 20, 30 may be selected to increase the surface area which can improve the foil's ability to dissipate heat and / or liquid, absorb energy, or interact with other materials, such as non-stick coatings and / or macro-embossing patterns. In some examples, the shape and size of the features and / or pattern of the micro-embossed areas may have wave-like and / or sinusoidal shapes that enhance the flexibility and durability of the embossed metallic foils 10, 20, 30 by allowing the foil to flex and stretch without tearing making it more durable.

[0035] In some examples, the emboss roll pressure and other process parameters used to fabricate the micro-embossed areas of the embossed metallic foils 10, 20, 30 may be selectively controlled to induce work hardening in the metal to increase its hardness and strength in the embossed regions. The above considerations relating to selecting the parameters of the micro-embossed areas of the embossed metallic foils 10, 20, 30 toimprove the balance or combination of their properties may also be applied in different combinations at a macro-level to the plurality of elevated and / or depressed embossed elements 12, 22, 32 that are also embossed into the metallic foils 10, 20, 30.

[0036] In some examples intended for use in cooking applications, a non-stick coating, such as a silicon non-stick coating, may be provided on one or both of the plurality of embossed elements 12, 22, 32 and the plurality of less embossed or unembossed areas. The non-stick coating may be provided on one or both sides of the metallic foil. In some examples, the metallic foil 10, 20, 30 may comprise a plurality of embossed elements 12, 22, 32 separated by a plurality of less-embossed areas, wherein the plurality of embossed elements 12, 22, 32 have a shiny visual appearance, wherein the plurality of less-embossed areas have a frosted or satin visual appearance, and wherein a non-stick coating is provided on one or both sides of the embossed metallic foil 10, 20, 30.

[0037] In some examples, the plurality of embossed elements 12, 22, 32 may have a height and / or depth between 0.03 mm and 2 mm, for example, between 0.1 mm and 0.5 mm. The plurality of embossed elements 12, 22, 32 may have a width of between 0.05 mm and 5 mm, for example, between 1 mm and 2 mm. The plurality of embossed elements 12, 22, 32 may be spaced apart from each other by between 0.3 mm and 3 mm, for example, between 2 mm and 2.5 mm. The metallic foil 10, 20, 30 may have a thickness between 0.010 mm and 0.20 mm, for example, between 0.012 mm and 0.017 mm. The plurality of embossed elements 12, 22, 32 may be perceptible visually and tactilely on one or both sides of the metallic foil. In some examples, the metallic foil 10, 20, 30 may comprise 8011 or 8006 aluminium alloy.

[0038] In some examples, the plurality of embossed elements 12, 22, 32 may be formed by cold rolling the metallic foils 10, 20, 30 between two rollers comprising a steel roller on which a relief was formed and a counter-roller of a resilient material. In other examples, both embossing rollers may comprise metal embossing rollers that in some examples provides roll-to-roll embossing. By impressing the relief of the male roller into the female counter-roller, the plurality of embossed elements 12, 22, 32 may be formed as single level embossing in the form of a plurality of elevated, embossed ribs 12, 22, 32 on one surface of the metallic foils 10, 20, 30. In other examples, the plurality of embossed elements 12, 22, 32 may be formed as multiple level embossing. In some examples, thecold working of the surface of the metallic foils 10, 20, 30 between the two rollers may increase the strength of the metallic foils 10, 20, 30 by cold strain hardening.

[0039] Examples of the present disclosure also provide metallic products (not shown) made from or comprising the metallic foils 10, 20, 30 described above. The metallic products may comprise foil sheets, foil rolls, foil roll dispensers, receptacles, trays, containers, lids, cookware, bakeware, food packages, and combinations thereof.

[0040] The following Examples are intended to illustrate the disclosure. They are not intended to limit the scope of the disclosure.Example 1 - All-purpose embossed aluminium foil

[0041] A all-purpose embossed aluminium foil 10 suitable for cooking and / or household applications was made from 8006 aluminium alloy by rolling between two metal embossing rollers. The aluminium foil 10 had a thickness of 0.012 mm or 12 pm. The plurality of embossed elements 12 had a height of 0.2 mm and a width of 1 mm, and were spaced from each other by 1.5 mm.

[0042] The plurality of embossed elements 12 comprised a repeating pattern of three concentric hexagons 12a, 12b, 12c, wherein four linear segments 12d are arranged in parallel inside an innermost concentric hexagon 12c. The repeating pattern was arranged diagonally across the aluminium foil 10.Example 2 - Heavy-duty embossed aluminium foil

[0043] A heavy-duty embossed aluminium foil 20 suitable for cooking and / or household applications was made from 8006 aluminium alloy by rolling between two metal embossing rollers. The aluminium foil 20 had a thickness of 0.015 mm or 15 pm. The plurality of embossed elements 22 had a height of 0.4 mm and a width of 2 mm, and were spaced from each other by 2 mm.

[0044] The plurality of embossed elements 22 comprised a repeating pattern of three concentric hexagons 22a, 22b, 22c. The three concentric hexagons 22a, 22b, 22ccomprised outer, middle, and inner concentric hexagons 22a, 22b, 22c. The outer hexagon 22a was defined by three linear segments arranged to form three parallel zigzag lines 22d, 22e, 22f. The inner hexagon 22c comprised a solid two-dimensional hexagon. The repeating pattern was arranged diagonally across the aluminium foil 20.Example 3 - Non-stick embossed aluminium foil

[0045] A non-stick embossed aluminium foil 30 suitable for cooking applications was made from 8011 aluminium alloy by rolling between two metal embossing rollers. The aluminium foil 30 had a thickness of 0.012 mm or 12 pm. The plurality of embossed elements 32 had a height of 0.2 mm and a width of 1 mm, and were spaced from each other by 1 mm. A non-stick silicon coating was provided on the embossing elements 32 and the unembossed areas.

[0046] The plurality of embossed elements 32 comprised a repeating pattern of four concentric hexagons 32a, 32b, 32c, 32d each having two adjacent sides left open to form four concentric hexagonal arches. The repeating pattern was arranged horizontally across the aluminium foil 30.Comparative Performance Testing

[0047] To evaluate the mechanical enhancements provided by the specific embossing patterns of the present disclosure, a series of comparative tests were performed on three distinct aluminum foil embodiments, namely the all-purpose foil of Example 1, the heavy-duty foil of Example 2, and the non-stick foil of Example 3. These examples were subjected to standardised tensile and durability testing in both their unembossed, flat state and their subsequent embossed state to quantify improvements in structural integrity. Tensile strength was measured using a vertical tensile tester to determine the maximum force in Newtons (N) before material failure, while puncture resistance was determined as the force required for a standardised probe to penetrate the foil surface. Additionally, tear resistance was evaluated by measuring the force required to propagate a tear across the material.

[0048] The results of this testing demonstrate a measurable increase in durability and formability across all material grades following the application of the hexagonal geometric arrays. For the 8006 12 pm alloy of Example 1, the maximum force increased from 125 N to 128 N and puncture resistance reached 2.8 N, while the elongation value remained constant at 1.5. This embodiment demonstrated the most significant proportional improvement in tear resistance, increasing from a baseline of 0.3 N in its unembossed state to 0.5 N after embossing.

[0049] Similarly, the 8006 15 pm alloy of Example 2 transitioned from an unembossed state characterized by a maximum force of 135 N, an elongation of 2, a puncture resistance of 2.79 N, and a tear resistance of 0.4 N to an embossed state exhibiting 137 N of maximum force, an elongation of 2, a puncture resistance of 2.9 N, and a tear resistance of 0.55 N. The 8011 12 pm alloy utilised in Example 3, upon embossing, showed an increase in maximum force from 95 N to 98 N, a puncture resistance of 2.9 N, and a tear resistance of 0.65 N, while maintaining an elongation value of 2.

[0050] These consistent elongation values across the embossed and unembossed states of the specific samples tested serve to establish a ductility and elasticity floor for the starting material. This data confirms that the mechanical deformation inherent in the hexagonal embossing process maintains the inherent structural integrity of the foil without inducing material embrittlement. The overall observed characteristics indicate that the hexagonal geometry provides a measurable structural reinforcement that increases the maximum force capacity and failure resistance of the metallic foil across varying gauges and alloys. The resulting increases in puncture and tear resistance further improve the formability of the sheet for practical applications.

[0051] The three examples of the aluminium foils 10, 20, 30 described above were tested for their intended cooking and / or household uses. All three examples were found to have improved combinations of mechanical, functional, and aesthetic properties compared to unembossed or conventional embossed aluminium foils. Furthermore, similar to the present applicant’s previously proposed repeating S-shaped embossing pattern discussed above, all three examples of the present disclosure were found to have increased rigidity and dimensional stability as compared with conventional smooth metal foils and prior art patterned or embossed foils. Also like the present applicant’s previouslyproposed repeating S-shaped embossing pattern, all three examples of the present disclosure were found to have improved cooking benefits that enable tastier, healthier, cleaner, faster, and more convenient cooking of foods with less oil and fat compared to existing smooth and embossed aluminium foils. However, the embossing pattern of all three examples of the present disclosure was easier to manufacture compared to the present applicant’s previously proposed repeating S-shaped embossing pattern due to the hexagonal geometry of their embossing patterns. In addition, the use of two metal embossing rollers in all three examples of the present disclosure provided a distinctive and aesthetically pleasing embossing pattern which was clearly perceptible both visually and tactilely compared to the weak and barely perceptible embossing patterns of conventional embossed aluminium foils made using a metal embossing roller and a rubber embossing roller.

[0052] Without wishing to be bound by theory, it is believed that the embossed elements have increased tensile strength compared to the less embossed and any unembossed metallic foils material, due to the strain hardening of the metallic foil material during embossing and the resultant microstructural orientation of the embossed metallic material. The embossed pattern consists of alternating strong, thinner rib formation material and the less-embossed thicker material between the rib formation(s). When a strain is encountered in the embossed zone, the thinner, stronger rib formations resist further lateral stretching, while the thicker, weaker less-embossed material yields more easily to the strain. A cushioning effect is therefore created to absorb the strain, thereby increasing puncture and tear resistance.

[0053] The hexagonal rib formation of the embossed patterns assists this by ensuring that the metallic foil material of the embossed patterns is able to stretch in all directions in the plane of the metallic foil, preferably equally. In other words, it is believed that the two-dimensional hexagonal close-packed arrangement of the embossed elements is adapted to enable adjacent unembossed or less-embossed regions to stretch to thereby increase resistance to punctures, while also increasing resistance to tear propagation, in the sheet of metallic foil.

[0054] Moreover, due to the hexagonal geometry, the continuous less-embossed or unembossed areas do not provide any location where a continuous, straight line can bedrawn across the metallic foils 10, 20, 30. This is important because a tear propagating in the continuous less-embossed or unembossed areas cannot follow a continuous path in the embossing direction, where the metallic foil 10, 20, 30 is inherently weaker. Instead, assuming the tear follows the edges of the plurality of embossed elements 12, 22, 32, the tear will follow a longer path that will be, at least partially, in the cross direction. Thus, as a tear propagates across the metallic foil 10, 20, 30, it will necessarily intersect with one of the plurality of embossed elements 12, 22, 32. Such tears will tend to propagate around the edges of the plurality of embossed elements 12, 22, 32 and into varying directions.

[0055] The geometry of the embossing shapes creates structural reinforcement that enhances dead-foldability and aesthetic appearance through deep deformations formed by metal-on-metal rollers.

[0056] The isotropic nature of the hexagonal grid ensures that properties such as liquid dispersion and heat conductivity are maintained uniformly across the sheet.

[0057] The hexagonal geometry described herein allows for significant performance improvements using standard 8011 or 8006 alloys, effectively substituting for higher-grade, more expensive aluminium alloys, such that higher tensile grades need not be utilised. The structural reinforcement provided by the hexagonal close-packed array enables significant material cost-optimisation through strategic grade substitution. As demonstrated by the recorded increases in maximum force across all embodiments -reaching up to 137 N for the 15 pm gauge - the geometric integrity of the pattern allows lower-cost metallic foil grades to achieve mechanical performance metrics previously associated with higher-tensile or thicker materials. Furthermore, the cold-rolling process utilised to form the plurality of embossed elements induces a beneficial strain hardening effect. This mechanical cold working effectively increases the material's peak force resistance and overall durability without necessitating chemical additives or supplementary thermal treatments.

[0058] A distinction exists between the hexagonal embossing of the present disclosure and similar patterns applied to rigid metal articles. Unlike rigid bodies, one or more embodiments of the metallic foil of the present disclosure operate within a micro-gauge regime, specifically between 0.012 mm and 0.017 mm. Within this range, the hexagonalgrid does not merely serve as a surface treatment but acts as a structural reinforcement that transforms a low-ductility foil (exhibiting a baseline elongation of 1.5% to 2%) into a three-dimensional mechanical lattice. In this micro-gauge context, the ratio of embossing depth to material thickness is at least 2:1, and in one or more embodiments, at least 15: 1. This geometric scaling ensures that the foil achieves a peak force capacity of up to 137 N, as verified in the comparative testing of Example 2, by leveraging the strain hardening induced during the cold-rolling process.

[0059] The present disclosure further distinguishes itself through the calibration of specific surface roughness, denoted as Ra. In the micro-gauge foil of the present disclosure, the embossing process is utilised to create a localised surface roughness gradient. The glossy embossed elements are characterised by a lower Racompared to the satin or frosted less-embossed areas. This dual-topology serves a specific mechanical function in thin-film applications: it reduces the "coefficient of friction" across the foil surface, preventing the localized "self-collision" of patterns that occur when foils are nested or stacked. This provides a functional durability and "dead-foldability" unique to flexible sheets.

[0060] Furthermore, the hexagonal close-packed array described herein is geometrically optimized to account for the "elastic recovery" or "spring-back" inherent in micro-gauge aluminum alloys. Because the foil is a flexible, ductile material, the hexagonal angles are specifically calibrated to maintain their three-dimensional profile after being released from the metal-on-metal embossing rollers. This allows the foil to maintain its increased tear resistance (increasing from a baseline of 0.3 N to 0.5 N) and puncture resilience during consumer handling.

[0061] The technical classification of the metallic foil is defined by a range of thicknesses suited for specific functional uses and structural needs in global markets. Rolled foil applications typically utilize thicknesses from 0.008 mm up to 1.00 mm while higher rigidity formed trays or deep drawn industrial containers utilize a gauge range extending up to 4.00 mm. Within these micro gauge and tray specific ranges, the hexagonal close packed array serves as a structural stabilizer designed to support the geometric displacement of the embossing elements even at a manufacturing tolerance of plus or minus 8%. This configuration ensures that the structural integrity of the foil remains intact across the specified thickness spectrum.

[0062] Within the household sector, the metallic foil is categorized by thickness to optimize the structural performance of the hexagonal reinforcement for specific cooking tasks. Standard foil is approximately 0.015 mm to 0.016 mm for wrapping sandwiches and light baking while heavy duty foil ranges from 0.023 mm to 0.024 mm for grilling or roasting. Extra heavy-duty variants are specified between 0.028 mm and 0.040 mm for commercial style cooking and ultra heavy or survival grade reaches a thickness of 0.076 mm for extreme durability in campfire cooking. In regional markets such as Australia, the practical thickness range is defined between 0.008 mm and 0.040 mm.

[0063] The present disclosure involves the mechanical performance of the foil being enhanced by the interaction between the hexagonal pattern and the 8000 series alloys. These alloys are primarily delivered in a fully annealed O temper to provide the ductility necessary for the foil to conform to the hexagonal dies without fracture. Certified production logs show that the synergistic effect of the pattern on a standard 8011 alloy at 0.015 mm gauge allows a baseline tensile strength of 95.0 MPa to be structurally maximized by the embossing geometry.

[0064] To achieve the desired structural reinforcement, the chemistry of these alloys follows strict industry standards. The standard 8011 alloy comprises an Iron or Fe content of 0.60% to 1.0% and a Silicon or Si content of 0.50% to 0.90% while Manganese or Mn is restricted to less than 0.20%. Certified chemical analysis confirms Si levels ranging from 0.5590% to 0.5670% and Fe levels from 0.7330% to 0.7660%. For specialised flexible packaging, an 8111 alloy may be used with a higher Si and Fe range of up to 1.1% to improve flexibility and the adhesion of coatings.

[0065] In premium embodiments, the present disclosure is realised through the use of the 8006 alloy where the high Iron content of 1.2% to 2.0% and Manganese content of 0.30% to 1.0% provide the high elongation backbone required for deep draw hexagonal elements. Testing results show that an Iron concentration of 1.6300% and Manganese levels of 0.2630% when cold worked into the hexagonal grid results in a performance profile characterized by a tensile strength of 154.0 MPa. While the 8006 alloy represents a higher cost per ton and lower market availability compared to 8011 , its combination withthe hexagonal embossing enables a premium performance without increasing material gauge.

[0066] For industrial grade tray applications, the hexagonal pattern is applied to 3003 series alloys to resolve the conflict between rigidity and formability. In a hard tempered H24 state, 3003 alloy production samples exhibit a tensile strength of 143.0 MPa and a high elongation of 21.30%. The chemical profile, which features Manganese levels up to 1.0780% and Iron levels of approximately 0.53%, provides a robust substrate that allows the hexagonal embossing to act as a structural lattice that prevents the buckling or collapse of tray walls.

[0067] The strategic tiering of these alloys validates the universal applicability of the hexagonal embossing elements where the 8011 alloy is utilised for cost sensitive applications to provide a competitive performance floor while the 8006 alloy is combined with the hexagonal embossing grid to produce the strongest available foil for premium brands. This combination of metallurgical grade and geometric reinforcement is intended to maintain the structural integrity of the foil across household and commercial gauges by leveraging the work hardening capacity of the material during the embossing process. This synergy ensures that the hexagonal pattern significantly improves the puncture resistance of the finished product.

[0068] To achieve a highly precise tactile feel and mechanical performance, the present disclosure contemplates a transition toward a very fine embossing scale. To achieve this refined profile, in one or more embodiments the plurality of embossed elements are calibrated to a height or depth range of 0.03 mm to 2 mm. At this detailed scale, the spacing between individual embossed elements is further optimized to a range of 0.03 mm to 3 mm. This micro scale configuration creates a dense structural matrix that improves the dead fold and tear propagation resistance of the foil.

[0069] The hexagonal reinforcement is adapted to operate across a wide range of global material standards from the thinnest Australian rolled foils to the thickest variants found in the United States. For rolled foil applications, the hexagonal pattern is applied to gauges ranging from 0.008 mm up to 1.00 mm which encompasses the 0.076 mm survival grade categories common in the United States market. This range is intended to maintain thestructural advantages of the hexagonal array as the material transitions from standard wrapping foil to high durability roasting applications.

[0070] The scope of the present disclosure extends to high thickness formed applications where the metallic substrate reaches a gauge of 4.00 mm. Within this gauge regime, the hexagonal elements function as a dynamic reinforcement lattice tailored to the strain hardening capacity of cold rolled and ductile alloys. This distinguishes the present disclosure from macro gauge rigid bodies such as non-deformable structural vessels because the reinforcement relies on the ductile elongation and surface roughness contrast of the microstructure to maintain structural integrity under load. By linking this thickness range to the tensile peaks of 154.0 MPa for the 8006 alloy (as used in Examples 1 and 2) and 143.0 MPa for the 3003 alloy, embodiments of the present disclosure provide a solution for high-capacity formed receptacles.

[0071] The present disclosure is not limited to the examples that have just been given. Those skilled in the art will appreciate that the examples may be reproduced without difficulty, and with similar success, by substituting or varying any of the generically or specifically described elements or sequence of method steps, mentioned anywhere in this specification forthose actually used in the preceding examples.

[0072] Embodiments of the present disclosure provide embossed metallic foils that are both generally and specifically useful for cooking and / or household applications.

[0073] Unless the context requires otherwise, the word "comprising" means "including but not limited to," and the word "comprises" has a corresponding meaning.

[0074] Any reference to prior art is not an admission that the prior art is common general knowledge.

[0075] The present disclosure is not limited to the examples given above. Instead, the scope of the present disclosure supported by the above examples is defined by the claims that follow.

Claims

Claims1. A metallic foil sheet, comprising:a plurality of embossing elements provided on at least one surface of the sheet; wherein all or a majority of the plurality of the embossed elements comprise at least three linear segments that are positioned in a parallel, intersecting, or concentric layout relative to each other on a hexagonal grid or tiling to form a two-dimensional hexagonal close-packed array or tessellation.

2. The metallic foil of claim 1, wherein all or a majority of the plurality of embossed elements comprise at least two concentric hexagons that are closed or partially open on a plurality of adjacent sides.

3. The metallic foil of claim 2, wherein an outer hexagon of the at least two concentric hexagons are defined by three linear segments arranged to form three parallel zig-zag lines.

4. The metallic foil of claim 3, wherein the three parallel zig-zag lines comprise a first zig-zag line, a second zig-zag line, and a third zig-zag line that collectively define the six vertices of the outer hexagon.

5. The metallic foil of claim 3, wherein an innermost hexagon of the at least two concentric hexagons comprise a solid two-dimensional hexagon.

6. The metallic foil of claim 2, wherein all or the majority of the plurality of embossed elements comprise a repeating pattern of a plurality of concentric hexagons each having two adjacent sides left open to form a plurality of concentric hexagonal arches.

7. The metallic foil of claim 2, wherein all or the majority of the plurality of embossed elements comprise a repeating pattern of three concentric hexagons comprising outer, middle and inner hexagons, wherein the outer hexagon is defined by three linear segments arranged to form three parallel zig-zag lines, and wherein the inner hexagon comprises a solid two-dimensional hexagon.

8. The metallic foil of claim 2, wherein all or the majority of the embossed elements comprise a repeating pattern of a plurality of concentric hexagons, and wherein a plurality of linear segments are arranged spaced apart in parallel inside an innermost concentric hexagon.

9. The metallic foil of claim 1, wherein the plurality of embossed elements are separated by a plurality of less-embossed or unembossed areas of the metallic foil wherein the less-embossed or unembossed areas form a continuous network surrounding the plurality of embossed elements.

10. The metallic foil of claim 9, wherein the plurality of less-embossed areas are microembossed to have a contrasting visual appearance relative to the plurality of embossed elements.

11. The metallic foil of claim 10, wherein the micro-embossed areas have a frosted or satin visual appearance, and the plurality of embossed elements have a shiny visual appearance.

12. The metallic foil of claim 11, further comprising a non-stick coating provided on one or both of the plurality of embossed elements and the plurality of less embossed or unembossed areas.

13. The metallic foil of claim 12, wherein the non-stick coating is provided on one or both sides of the metallic foil.

14. The metallic foil of claim 1 , wherein the metallic foil comprises a shiny side and a dull side, and wherein the plurality of embossed elements are embossed in the shiny side.

15. The metallic foil of claim 1, wherein the plurality of embossed elements have a height and / or depth between 0.03 mm and 2 mm.

16. The metallic foil of claim 15, wherein the plurality of embossed elements have a height and / or depth between 0.1 mm and 0.5 mm.

17. The metallic foil of claim 1, wherein the plurality of embossed elements have a width of between 0.05 mm and 5 mm.

18. The metallic foil of claim 1, wherein the plurality of embossed elements are spaced apart from each other by between 0.03 mm and 3 mm.

19. The metallic foil of claim 1, wherein the plurality of embossed elements are perceptible visually and tactilely on one or both sides of the metallic foil.

20. The metallic foil of claim 1 , wherein the metallic foil has a thickness between 0.008 mm and 4 mm.

21. The metallic foil of claim 1, wherein the metallic foil comprises 8011 or 8006 aluminium alloy.

22. The metallic foil of claim 1 , wherein a ratio of the height of the embossed elements to the thickness of the metallic foil is at least 2:1.

23. A metallic product or article made from or comprising the metallic foil of claim 1.

24. The metallic product or article of claim 23, wherein the metallic product or article comprises a foil sheet, a foil roll, a foil roll dispenser, a receptacle, a tray, a container, a lid, cookware, bakeware, a food package, and combinations thereof.

25. An embossed metallic foil, comprising a plurality of embossed elements separated by a plurality of less-embossed areas, wherein the plurality of embossed elements have a shiny visual appearance, wherein the plurality of less-embossed areas have a frosted or satin visual appearance, and wherein a non-stick coating is provided on one or both sides of the embossed metallic foil.

26. A method of manufacturing the metallic foil of claim 1, comprising rolling the metallic foil between two metal embossing rollers to induce strain hardening.

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