FORM 2
THE PATENT ACT, 1070
(39 OF 1970)
AND
THE PATENT RULES, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. TITLE OF THE INVENTION
EMBOSSED FOIL FOR PRESERVING AND PACKING FOOD

2. APPLICANT:
(a). Name: Gujarat Foils Limited
(b). Nationality: Indian Company
(c). Address: 3436-3439, Chhatral, G.I.D-C, Phase-IV, Tal. - Kalol, Dist. Gandhinagar Gujarat - 382729, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
The present invention relates to an embossed metal foil for preserving and packing of food stuffs. The invention further relates to a process of preparing the embossed metal foil.
BACKGROUND AND PRIOR ART
Foil wraps for packaging of food stuffs are widely known in the art. Metallic foils such as aluminium foils have been used for several years for household cooking purposes, food packaging and other applications. These household metal foils generally consist of smooth shiny thin sheet material. However, these conventional metal foils are slippery and exhibit problems such as running off of the cooking fluids and sticking of the foils to cooked food. These foils also display poor strength, rigidity, stretchability, foldability and tearability.
To eliminate the above-stated drawbacks several techniques have been proposed in the prior art. Plastic laminates have been added to smooth metal foils to reduce sticking, prevent run-off of the foodstuff and increase the strength of the foil.
WO2008022397 discloses a household metal foil which is embossed. The embossing pattern includes undulations having an S-shaped plan shape

as illustrated in FIGURE 1. The undulations are mutually arranged closely adjacent to each other so that the passage of the cooking fluids from the plane of the sheet is omni-directionally controlled. However, such foils are expensive to manufacture.
Hence, there is a need to manufacture a metal foil for preserving and packing food stuff, wherein the foil displays increased tensile strength and is highly tamper-proof while being aesthetically appealing to the eyes. There is a further need to develop a simple, cost-effective and a satisfactory method of manufacturing the metal foil for preserving and packaging foodstuffs.
SUMMARY OF THE INVENTION
The invention relates to a metal foil for preserving and packaging food stuffs, wherein at least one side of the metal foil is embossed with an embossing pattern, the embossing pattern comprising:
a plurality of outer polygons, wherein the plurality of the outer polygons is interconnected on the sides to form a continuous symmetric network on the at least one side of the metal foil; and,
a plurality of inner polygons, wherein the plurality of the inner polygons is enclosed within the plurality of outer polygons.

The invention relates to a metal foil for preserving and packaging food stuffs, wherein at least one side of the metal foil is embossed with an embossing pattern, the embossing pattern comprising:
a plurality of outer quadrangular structures, wherein the plurality of the outer quadrangular structures is interconnected on the sides to form a continuous symmetric network on the at least one side of the metal foil;
and,
a plurality of inner quadrangular structures, wherein the inner quadrangular structures are enclosed within the outer quadrangular structures.
A metal foil for preserving and packaging food stuffs, wherein at least one side of the metal foil is embossed with an embossing pattern, the
embossing pattern comprising:
a plurality of outer curved structures, wherein the plurality of the outer curved structures is interconnected on the sides to form a continuous symmetric network on the at least one side of the metal foil; and,
a plurality of inner curved structures, wherein the inner curved structures are enclosed within the outer curved structures.
The invention further relates to a process of embossing a metal foil, the process comprising steps of:

a. providing a parent roll of a metal foil, wherein the metal
foil has a thickness gauge of and less than 200 microns;
b. passing the metal foil through a plurality of guide rollers to
reach an embosser; and,
c. pressing the metal foil in between at least two rolls in the
embosser to impart an embossed texture to the metal foil.
The invention further relates to the use of the embossed metal foil in manufacturing articles for preserving and packing of food materials.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of embodiments of the invention.
FIGURE 1 illustrates an exploded view of a prior art embossed metal foil having an embossing pattern which includes undulations having an S- shaped plan shape.
FIGURE 2 illustrates a front view of an embossed metal foil in accordance with an embodiment of the invention.
FIGURE 3 illustrates an exploded view of the embossing pattern of the metal foil in accordance with an embodiment of the invention.

FIGURE 4 is an enlarged view of the embossing pattern illustrating the dimensions in accordance with an exemplary embodiment of the present invention.
It is to be understood that the drawings are not to scale and are schematic in nature. In certain instances, details which are not necessary for an understanding of the present invention or which renders other details difficult to perceive, may be omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
DETAILED DESCRIPTION OF THE INVENTION
In describing the embodiments of the invention, specific terminology is used for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.
While the present invention is susceptible of embodiments in various forms, there will hereinafter be described presently preferred embodiments with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments described.

The present invention relates to a metal foil for preserving and packaging of food stuffs.
The metal foil is embossed on one side or on both the sides with an embossing pattern. The embossing pattern includes a plurality of outer polygons which are interconnected on the sides to form a continuous symmetric network on the surface of the metal foil. The embossing pattern further includes a plurality of inner polygons which are enclosed within the plurality of the outer polygons.
According to an embodiment, the outer polygons can have three or more sides. The outer polygons can have shapes such as triangles, quadrilaterals, pentagons, hexagons, octagons, star polygons, etc. One skilled in the art will appreciate that other polygonal shapes known in the art are also within the scope of the present invention.
According to another embodiment, the inner polygons can have three or more sides. The inner polygons can have shapes such as triangles, quadrilaterals/ pentagons, hexagons, octagons, star polygons, etc. One skilled in the art will appreciate that other polygonal shapes known in the art are also within the scope of the present invention.

According to an embodiment as shown in FIGURE 2, the metal foil (200) is embossed with an embossing pattern (210). The embossing pattern (210) can be provided on one or on both the sides of the metal foil.
According to an embodiment as shown in FIGURE 3, the embossing pattern (210) has a plurality of outer quadrangular structures (310) on the surface of the foil (200). The plurality of outer quadrangular structures (310) is interconnected on the sides to each other to form a continuous symmetric network (330) on the surface of the metal foil.
The embossing pattern further Includes a plurality of inner quadrangular structures (320). These inner quadrangular structures (320) are enclosed within the plurality of outer quadrangular structures (310).
According to an embodiment of the invention, the metal foil (200) is made of aluminium or an aluminium alloy. The aluminium foils may be of the series AA1XXX, AA3XXX, or AA8XXX.
According to a further embodiment, the metal foil is preferably made of aluminium. However, it will be appreciated by those skilled in the art that other thermally conductive foil materials may be substituted for the aluminum or aluminum alloy foil.
According to a further embodiment of the invention, the metal foil (200) has a thickness gauge of and less than 200 microns.

According to a still further embodiment, the embossing pattern on the metal foil has a height of about 0.01 mm. to about 5 mm.
According to one exemplary embodiment, as shown in FIGURE 4, the length (410) of the outer quadrangular structure (310) is about 1.14 mm. The lengths of the first diagonal (420) and the second diagonal (430) of the outer quadrangular structure (310) are about 2.263 mm. each. The length (450) of the inner quadrangular structure (320) is about 0.65 mm. The lengths of the first diagonal (460) and the second diagonal (470) of the inner quadrangular structure (320) are about 1.273 mm. each. The distance (440) between the outer quadrangular structure (310) and the inner quadrangular structure (320) is about 0.25 mm. The embossing pattern (400) on the surface of the metal foil (200) has a height (480) of about 1.14mm. However, those skilled in the art will appreciate that the above-stated dimensions are only exemplary and that the embossing pattern comprising the outer quadrangular structure (310) and the inner quadrangular structure (320) having varying dimensions is well within the scope of the invention.
According to another embodiment, the invention relates to a metal foil for preserving and packaging food stuffs. The metal foil is embossed on one or both the sides with an embossing pattern which includes a plurality of outer curved structures which are interconnected on the sides to form a

continuous symmetric network on the foil surface. The outer curved structures can have either a circular or an oval shape. The embossing pattern further includes a plurality of inner curved structures, wherein the inner curved structures are enclosed within the outer curved structures. The inner curved structures can also be circular or oval in shape.
According to a further embodiment, the invention relates to a process of embossing the metal foil useful for the packaging of the food stuffs. The process involves providing a parent roll of a metal foil having a thickness gauge of and less than 200 microns. The metal foil is unwound from the parent roll and passed through a plurality of guide rollers to reach an embosser. When the foil reaches the embosser, it gets pressed between at least two rollers in the embosser to impart an embossed texture to the metal foil. The rollers include an engraved roller precisely engraved with the desired embossing pattern and a rubber roller of a pre-determined hardness. The pattern on the engraved roller is thereby transferred to the metal foil.
According to another embodiment, the invention relates to the use of the embossed metal foil in manufacturing articles for storing and packing of food materials.

According to yet another embodiment; the invention relates to articles formed from the embossed metal foil. The articles can be selected from a foil sheet, a foil roll, foil roll dispenser, a receptacle, a tray, a container, a lid, a cookware, a bakeware, a food package and combinations thereof.
The embossed metal foil of the present invention displays geometrical rigidity because of the embossing pattern attained during the process of embossing of the foil thereby increasing the strength of the foil. The embossed surface imparts better grip to the foil. The embossed foil has greater tensile strength and therefore does not get easily torn. The embossing reduces contact with the food material as compared to the plain foil thus minimizing sticking of the food to the surface of the foil. Further, the process used for the manufacture of the embossed metal foil of the invention is found to be highly cost effective.
Although the disclosure of system and method has been described in connection with the embodiment of the present invention illustrated in the accompanying drawings, it is not limited thereto. It will be apparent to those skilled in the art that various substitutions, modifications and changes may be made thereto without departing from the scope and spirit of the disclosure.

CLAIMS
We claim:
1. A metal foil for preserving and packaging food stuffs, wherein at
least one side of the metal foil is embossed with an embossing
pattern, the embossing pattern comprising:
a plurality of outer polygons, wherein the plurality of outer polygons is interconnected on the sides to form a continuous symmetric network on the at least one side of the metal foil; and, a plurality of inner polygons, wherein the plurality of the inner polygons is enclosed within the plurality of outer polygons.
2. The metal foil of claim 1, wherein the outer polygon comprises at least three sides.
3. The metal foil of claim 1, wherein the inner polygon comprises at least three sides.
4. The metal foil of claim 1, wherein the metal foil comprises one of an aluminium foil and an aluminium alloy foil.
5. The metal foil of claim 1, wherein the metal foil is an aluminium foil.

6. The metal foil of claim 1, wherein the metal foil has a thickness gauge of and less than 200 microns.
7. The metal foil of claim 1, wherein the embossing pattern has a height of about 0.01 mm to about 5 mm.
8. A metal foil for preserving and packaging food stuffs, wherein at least one side of the metal foil is embossed with an embossing pattern, the embossing pattern comprising:
a plurality of outer quadrangular structures, wherein the plurality of the outer quadrangular structures is interconnected on the sides to form a continuous symmetric network on the at least one side of the metal foil; and,
a plurality of inner quadrangular structures, wherein the inner quadrangular structures are enclosed within the outer quadrangular structures.
9. A metal foil for preserving and packaging food stuffs, wherein at
least one side of the metal foil is embossed with an embossing
pattern, the embossing pattern comprising:
a plurality of outer curved structures, wherein the plurality of outer curved structures is interconnected on the sides to form a continuous symmetric network on the at least one side of the metal foil; and,

a plurality of inner curved structures, wherein the inner curved structures are enclosed within the outer curved structures.
10.The metal foil of claim 9, wherein the outer curved structure is a
circle or an oval.
11. The metal foil of claim 9, wherein the inner curved structure is a
circle or an oval.
12. A process of embossing a metal foil, the process comprising steps of:
a. providing a parent roll of a metal foil, wherein the metal
foil has a thickness gauge of and less than 200 microns;
b. passing the metal foil through a plurality of guide rollers to
reach an embosser; and,
c. pressing the metal foil between at least two rolls in the
embosser to impart an embossed texture to the metal foil.
13. Use of the metal foil of claim 1 in manufacturing articles for storing and packing of food materials.
14. An article formed from the metal foil of claim 1.
15.The article of claim 14, wherein the article is selected from a foil sheet, a foil roll, a foil roll dispenser, a receptacle, a tray, a container, a lid, a cookware, a bakeware, a food package and combinations thereof.

16.A metal foil substantially as herein described with reference to the accompanying drawings.