The present invention provides a plastic free oxygen and moisture barrier coated metallised paper based structure for packaging applications where water vapour and oxygen barrier properties are essential.
BACKGROUND OF THE INVENTION:
For packaging of items that can lose their desired end properties such as aroma, crispness, freshness, taste, texture and shelf-life due to the permeation of oxygen and/or water vapour, in particular food products, it is highly required to prevent the permeation of oxygen and/or water vapour through the surface of the packaging material.
To prevent the deterioration of such products several efforts have been made in the past, especially the efforts have centred on use of plastic films as one of the layers in the laminate. One such plastic film is polyethylene terephthalate (PET) or metallised PET to improve its barrier properties. Metallisation is the process of applying a metallic coating onto a substrate surface, and the metallisation can be done through various processes such as vacuum metallisation, physical evaporation, sputtering, indirect metallisation, plating, or painting. Most common method of metallisation is vacuum deposition, and the metal used for this purpose is aluminium. The metallisation process involves the steps of heating the metal (e.g. aluminium), melting and evaporating the metal in a chamber under high vacuum, and migration of the evaporated vapour through the chamber that condenses on cooler substrate surfaces to form the metallisation layer.
Of late, use of paper in packaging laminates is drawing attention because of environmental concerns of biodegradability of plastic films.
Paper is porous, has an uneven surface, and has pin holes, so metallised paper was introduced.
In some attempts, a laminate is formed by adding a PET layer between a paper layer and a foil. However because of the PET layer used and the biodegradability of the laminate material is an environmental concern.

CN102896857B discloses a paper-based aluminium-plastic composite material that consists of several polyethylene layers
US2017320305A1 discloses a laminate that includes a heat sealable material, a cyclic olefin copolymer layer, a metallic foil or metallised polymer material, and a thermoplastic film or paper layer.
JP2007090837A discloses a paper laminate obtained by applying an anchor coating agent on a paper substrate, and laminating a metal vapor-deposition layer on the above coated layer or impregnated layer.
US2007110932A1 discloses a packaging material comprising an outer layer of kraft paper, a centre layer of high-barrier metallised polyethylene terephthalate (PET), and an inner layer of linear low density polyethylene (LDPE).
JP2001088262A discloses a laminated material, where a metallic or inorganic oxide vapour deposition film is applied to one face of a thin polyester resin film.
Despite the presence of high-barrier films, the prior art does not provide a water vapour and oxygen barrier packaging materials which exhibit superior water vapour/ moisture and oxygen barrier properties, improved printability, excellent tear resistance.
Accordingly, it is required to provide a packaging material that provides the above said properties.
OBJECTS OF THE INVENTION:
The principal objective of the present invention is to provide a plastic free oxygen and moisture barrier coated metallised paper based structure for packaging applications with excellent water vapour and oxygen barrier properties.
A further objective of the present invention is to provide a plastic free oxygen and moisture barrier coated metallised paper based structure for packaging applications

that exhibits excellent printability.
Yet another objective of the present invention is to provide a plastic free oxygen and moisture barrier coated metallised paper based structure for packaging applications with improved tear resistance.
SUMMARY OF THE INVENTION:
The present invention provides a plastic free oxygen and moisture barrier coated metallised paper based structure obtained by providing a paper substrate (PAPER) having a first planar surface and a second planar surface, an oxygen barrier coating (OBC) is applied to the first planar surface of the paper substrate (PAPER), a layer of adhesive (ADH) is applied on the oxygen barrier coating (OBC), a metallised layer (MET) is deposited on ADH layer, a water vapour/moisture barrier coating (MBC) layer is applied above the metallised layer (MET), a printing ink (INK) layer is applied on the MBC layer; and a sealant i.e. a heat seal Lacquer (HSL) is applied to the second planar surface of PAPER.
The packaging material has excellent water vapour and oxygen barrier properties, improved printability, improved tear resistance.
The plastic free oxygen and moisture barrier coated metallised paper based structure in some embodiments of the present invention includes a protective gloss coating layer or a protective matte coating layer above the INK layer.
The plastic free oxygen and moisture barrier coated metallised paper based structure in some embodiments of the present invention includes a protective gloss coating layer or a protective matte coating layer between the MBC layer and the INK layer.
In some other embodiments, the plastic free oxygen and moisture barrier coated metallised paper based structure includes two protective coating layers, wherein a first protective coating layer is provided between the MBC layer and the INK layer, and a second protective coating layer is provided above the INK layer. The first and second protective coating layers can both be gloss coating, both be matte coating, or any one of them may be gloss coating and the other is matte coating.

BRIEF DESCRIPTION OF THE DRAWINGS:
Fig. 1 illustrates a plastic free oxygen and water vapour barrier paper based packaging structure represented as sealant/ paper/ oxygen barrier coating/ adhesive/ metallisation layer/ moisture barrier coat / printing Ink.
Fig. 2 illustrates a plastic free oxygen and water vapour barrier paper based packaging structure represented as sealant/ paper/ oxygen barrier coating/ adhesive/ metallisation layer/ moisture barrier coat / printing Ink/ protective gloss coating.
Fig. 3 illustrates a plastic free oxygen and water vapour barrier paper based packaging structure represented as sealant/ paper/ oxygen barrier coating/ adhesive/ metallisation layer/ moisture barrier coat / printing Ink/ protective matte coating.
Fig. 4 illustrates a plastic free oxygen and water vapour barrier paper based packaging structure represented as sealant/ paper/ oxygen barrier coating/ adhesive/ metallisation layer/ moisture barrier coat / first protective gloss or matte coating / printing Ink/ second protective gloss or matte coating.
DETAILED DESCRIPTION OF THE INVENTION:
The preferred embodiments of the present invention will be described in detail with the following disclosure and examples. The foregoing general description and the following detailed description are provided to illustrate only some embodiments of the present invention and not to limit the scope of the present invention. The invention is capable of other embodiments and can be carried out or practiced in various other ways.
Unless otherwise specified, all the technical and scientific terms used herein have the same meaning as is generally understood by a person skilled in the art pertaining to the present invention. All the patents, published patent applications referred to throughout the entire disclosure herein, unless specified otherwise, are incorporated by reference in their entirety.
Reference throughout this specification to "one embodiment," "an embodiment," "one example," or "an example" means that a particular feature, structure, or characteristic

described in connection with the embodiment or example is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” “one example,” or “an example” in various places throughout this specification are not necessarily all referring to the same embodiment 5 or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combinations and/or sub-combinations in one or more embodiments or examples. In addition, it should be appreciated that if any figures are provided herewith, they are for explanation purposes to persons ordinarily skilled in the art and that the drawings of them are not necessarily drawn to scale.
10
In this specification, certain aspects of one embodiment include process steps and/or operations and/or instructions described herein for illustrative purposes in a particular order and/or grouping. However, the particular order and/or grouping shown and discussed herein are illustrative only and not limiting. Those of skill in the art will
15 recognise that other orders and/or grouping of the process steps and/or operations and/or instructions are possible and, in some embodiments, one or more of the process steps and/or operations and/or instructions discussed above can be combined and/or deleted and/or interchanged. In addition, portions of one or more of the process steps and/or operations and/or instructions can be re-grouped as
20 portions of one or more other of the process steps and/or operations and/or instructions discussed herein. Consequently, the particular order and/or grouping of the process steps and/or operations and/or instructions discussed herein do not limit the scope of the disclosure.
25 In this specification, the terms “water vapour”, “vapour” and “moisture” may have been used interchangeably and they mean the same.
Similarly, the terms “water vapour barrier”, “vapour barrier” and “moisture barrier” may have been used interchangeably and they mean a layer of barrier coating 30 provided in the packaging material structure of the present invention to curtail or stop the permeation of water vapour from the surroundings through the surface of the packaging material structure.
The present invention provides a plastic free oxygen and moisture barrier coated
35 metallised paper based structure obtained by providing a paper substrate (PAPER)
having a first planar surface and a second planar surface, an oxygen barrier coating
(OBC) is applied to the first planar surface of the paper substrate (PAPER), a layer of
[6]

adhesive (ADH) is applied on the oxygen barrier coating (OBC), a metallised layer (MET) is deposited on ADH layer, a water vapour/moisture barrier coating (MBC) layer is applied above the metallised layer (MET), a printing ink (INK) layer is applied on the MBC layer; and a sealant i.e. a heat seal Lacquer (HSL) is applied to the 5 second planar surface of PAPER.
In one embodiment of the present invention, as shown in Fig. 1, a plastic free oxygen and moisture barrier coated metallised paper based structure (10) is provided. The plastic free oxygen and moisture barrier coated metallised paper based structure (10)
10 comprising of a paper substrate (PAPER) (101) having a first planar surface (101a) and a second planar surface (101b), a layer of oxygen barrier coating (OBC) (102) applied on the first surface (101a) of the PAPER, a layer of adhesive (ADH) (103) is applied on the OBC, a metallised layer (MET) (104) deposited on the ADH (103), a moisture barrier coating (MBC) layer (105) applied above the MET layer (104), a
15 printing ink layer (INK) (106) formed on the MBC layer (105); and a sealant i.e. a heat seal Lacquer (HSL) (107) applied to the second planar surface (101b) of the PAPER. The structure of Fig. 1 may be defined as HSL/ PAPER/ OBC/ ADH/ MET/ MBC / INK.
20 It is also observed that providing a protective gloss coating layer or a protective matte coating layer above the printing ink layer provides the plastic free oxygen and moisture barrier coated metallised paper based structure with additional benefits such as better aesthetics, and improved barrier properties.
25 In a second embodiment of the present invention, the plastic free oxygen and moisture barrier coated metallised paper based structure may optionally comprise of a protective gloss coating layer on top of the printing ink layer. As shown in Fig. 2, a plastic free oxygen and moisture barrier coated metallised paper based structure (20) is provided. The plastic free oxygen and moisture barrier coated metallised paper
30 based structure (20) comprising of a paper substrate (PAPER) (201) having a first planar surface (201a) and a second planar surface (201b), a layer of oxygen barrier coating (OBC) (202) applied on the first surface (201a) of the PAPER, a layer of adhesive (ADH) (203) is applied on the OBC, a metallised layer (MET) (204) deposited on the ADH (203), a moisture barrier coating (MBC) layer (205) applied
35 above the MET layer (204), a printing ink layer (INK) (206) formed on the MBC layer
[7]

(205), a protective gloss coating (PGC) layer (207) applied on the INK layer (206); and a sealant i.e. a heat seal Lacquer (HSL) (208) applied to the second planar surface (101b) of the PAPER. The structure of Fig. 2 may be defined as HSL/ PAPER/ OBC/ ADH/ MET/ MBC / INK/ PGC. 5
In a third embodiment of the present invention, the plastic free oxygen and moisture barrier coated metallised paper based structure may optionally comprise of a protective matte coating layer on top of the printing ink layer. As shown in Fig. 3, a plastic free oxygen and moisture barrier coated metallised paper based structure (30)
10 is provided. The plastic free oxygen and moisture barrier coated metallised paper based structure (30) comprising of a paper substrate (PAPER) (301) having a first planar surface (301a) and a second planar surface (301b), a layer of oxygen barrier coating (OBC) (302) applied on the first surface (301a) of the PAPER, a layer of adhesive (ADH) (303) is applied on the OBC, a metallised layer (MET) (304)
15 deposited on the ADH (303), a moisture barrier coating (MBC) layer (305) applied above the MET layer (304), a printing ink layer (INK) (306) formed on the MBC layer (305), a protective matte coating (PMC) layer (307) applied on INK layer (306); and a sealant i.e. a heat seal Lacquer (HSL) (308) applied to the second planar surface (301b) of the PAPER. The structure of Fig. 3 may be defined as HSL/ PAPER/ OBC/
20 ADH/ MET/ MBC / INK/ PMC.
In a fourth embodiment of the present invention, two protective coating layers are provided in the plastic free oxygen and moisture barrier coated metallised paper based structure, wherein a first protective coating (FPC) layer is provided between
25 the MBC layer and the INK layer, and a second protective coating (SPC) layer is provided above the INK layer. The FPC and SPC layers can both be gloss coating, both be matte coating, or any one of them may be gloss coating and the other matte coating. Such an arrangement provides the plastic free oxygen and moisture barrier coated metallised paper based structure with additional benefits of better aesthetics,
30 and further improved barrier properties.
As shown in Fig. 4, a plastic free oxygen and moisture barrier coated metallised
paper based structure (40) is provided. The plastic free oxygen and moisture barrier
coated metallised paper based structure (40) comprising of a paper substrate
35 (PAPER) (401) having a first planar surface (401a) and a second planar surface
[8]

(401b), a layer of oxygen barrier coating (OBC) (402) applied on the first surface (401a) of the PAPER, a layer of adhesive (ADH) (403) is applied on the OBC, a metallised layer (MET) (404) deposited on the ADH (403), a moisture barrier coating (MBC) layer (405) applied above the MET layer (404), a first protective gloss (FPG) 5 coating layer or a first protective matte (FPM) coating layer (406) applied on the MBC layer (405), a printing ink layer (INK) (407) formed on the FPG coating layer or the FPM coating layer (406), and a second protective gloss (SPG) coating layer or a second protective matte (SPM) coating layer (408) applied on the INK layer (407); and a sealant i.e. a heat seal Lacquer (HSL) (409) applied to the second planar 10 surface (401b) of the PAPER. The structure of Fig. 4 may be defined as HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPG or FPM/ INK/ SPG or SPM.
Specifically for the fourth embodiment, the following structures are possible according to the teachings of the present invention. 15
Structure comprising: HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPG / INK/ SPG
Structure comprising: HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPM/ INK/ SPM
20 Structure comprising: HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPG / INK/ SPM
Structure comprising: HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPM/ INK/ SPG
In a fifth embodiment of the invention, in the plastic free oxygen and moisture barrier 25 coated metallised paper based structure (40) of Fig. 4, where protective gloss coating is used in both the protective layers 406 and 408, and the FPG and SPG coatings are of the same composition, they are represented as FPGS and SPGS. This structure may be defined as HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPGS / INK/ SPGS. 30
In a sixth embodiment of the invention, in the plastic free oxygen and moisture barrier coated metallised paper based structure (40) of Fig. 4, where protective gloss coating is used in both the protective layers 406 and 408, and the FPG and SPG coatings are of different compositions, they are represented as FPGD and SPGD.
[9]

This structure may be defined as HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPGD / INK/ SPGD.
Similarly, when both the protective layers are of matte type, and the FPM and SPM 5 coatings are of the same composition, they are represented as FPMS and SPMS, and where the FPM and SPM coatings are of different compositions, they are represented as FPMD and SPMD, resulting in the following structures.
Structure comprising: HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPMS / INK/ SPMS. 10
Structure comprising: HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPMD / INK/ SPMD.

Abbreviations:
(HSL) heat seal Lacquer
(PAPER) paper substrate
(OBC) oxygen barrier coating
(ADH) adhesive layer
(MET) metallised layer
(MBC) moisture barrier coating
(INK) printing ink layer
(PGC) protective gloss coating
(PMC) protective matte coating
(FPG) first protective gloss coating layer
(FPM) first protective matte coating layer
(SPG) second protective gloss coating layer
(SPM) second protective matte coating layer
(FPGS, SPGS) FPG and SPG compositions are same
(FPMS, SPMS) FPM and SPM compositions are same
(FPGD, SPGD) FPG and SPG compositions are different
(FPMD, SPMD) FPM and SPM compositions are different
The oxygen barrier coating (OBC) is sold as MIchem® Flex B 1000 manufactured by Michelman.
35 The moisture barrier coating (MBC) is sold as VC1300® manufactured by Michelman.
[10]

The Adhesive (ADH) is selected from a one component solvent-less adhesive sold as HERBERTS 1K-LS 190N manufactured by Bostik, or a two component solvent base adhesive sold as EPS7280 / hardener KN 75 manufactured by Bostik. 5
The printing ink (INK) is selected from a Nitrocellulose-Polyurethane based ink, a Nitrocellulose based ink, preferably the INK is a Nitrocellulose based ink and procured from Yansefu® Inks and Coatings Pvt. Ltd. sold as Sarjo®foil.
10 The protective gloss coating (PGC) is selected from a Ultrviolet (UV) based gloss coating, a over protection varnish (OPV) based gloss coating, preferably the PGC is OPV based gloss coating and procured from Yansefu® Inks and Coatings Pvt. Ltd. sold as Sarjo®coat.
15 The protective matte coating (PMC) is selected from a over protection varnish (OPV) based matte coating, a Polyurethane (PU) based matte coating, preferably the PMC is PU based matte coating and procured from Yansefu® Inks and Coatings Pvt. Ltd. sold as Sarjo®film.
20 The heat seal Lacquer (HSL) is an acrylic copolymer sold as MIchem® Flex 1335 manufactured by Michelman.
The paper substrate in the plastic free oxygen and moisture barrier coated metallised paper based structure of the present invention is selected from a white paper, 25 gravure paper, art paper, kraft paper, glassine paper, glossy paper, matte paper, paraffin paper. Preferably white paper is used.
The areal density of the paper substrate is about 25 gsm to 100 gsm, preferably about 50 gsm to 75 gsm.
30
The oxygen barrier coating, the moisture barrier coating, the adhesive, and the protective coating layers can be applied by a suitable method known in the industry such as a gravure method, a knife coating method or comma method, an air knife method, a reverse roll method, or a hand coat method using a bar coater.
35
[11]

Number of coats of each of the oxygen barrier coating, the moisture barrier coating, the adhesive, and the protective coating layers is not particularly limited, preferably about 1 to 2 coats to make it cost effective.
5 The purpose of applying the metallisation layer on the adhesive layer in the plastic free oxygen and moisture barrier coated metallised paper based structure of the present invention is to help in providing a water vapour transmission rate (WVTR) of the structure <3.0 (g/m2/24 hours), and an oxygen transmission rate (OTR) <3.0 (cc/m2/24 hours).
10
Examples of the metal used for the deposition of metallised layer include aluminium, copper, zinc, tin, magnesium, and oxides thereof, and also silica. For a packaging article involving food, pharmaceuticals, and cosmetics, considering safety and hygiene, the metal used for the deposition of metallised layer preferably include
15 aluminium, and silica, more preferably the metal used is aluminium.
The metallisation layer can be formed by using any suitable method known in the industry selected from transfer metallisation, vacuum metallisation. Preferably the metallisation layer can be formed by transfer metallisation method.
20
In the embodiments, where a protective coating is applied in the plastic free oxygen and moisture barrier coated metallised paper based structure of the present invention, the purpose of applying such protective coating layer is to provide protection to the structure while using the structure in the packaging machine as well
25 as to provide improved barrier properties to the structure.
In the plastic free oxygen and moisture barrier coated metallised paper based structure of the present invention, the oxygen barrier coating is applied in an amount of about 2.0 to 5.0 gsm, preferably about 4.0 gsm. 30
The adhesive is applied in an amount of about 2.0 to 4.0 gsm, preferably about 3.0 gsm.
The moisture barrier coating is applied in an amount of about 2.0 to 4.0 gsm, 35 preferably about 3.0 gsm.
[12]

The protective coatings are applied in an amount of about 0.5 to 2.5 gsm, preferably about 1.0 gsm.
5 The heat seal lacquer is applied in an amount of about 2.0 to 4.0 gsm, preferably about 3.0 gsm.
The metallisation layer is deposited with optical density (OD) of about 1.0 – 3.0, preferably about 2.0. 10
Examples:
The present disclosure will now be explained in further detail by the following examples. These examples are illustrative of certain embodiments of the invention without being limited to the specific examples given here. 15
Example 1 to 4
According to seven preferred embodiments of the invention, the arrangements of the plastic free oxygen and moisture barrier coated metallised paper based structure are given below in Table 1. 20
Table 1

Structure
Example 1 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / INK
Example 2 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / INK/ PGC
Example 3 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / INK/ PMC
Example 4 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPG / INK/ SPG
Example 5 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPM/ INK/ SPM
Example 6 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPG / INK/ SPM
Example 7 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPM/ INK/ SPG
25
[13]

Example 8 to 11
According to four other preferred embodiments of the invention, the arrangements of the plastic free oxygen and moisture barrier coated metallised paper based structure, where two protective coatings are used, (a first protective coating is applied on the 5 barrier coating layer, and the second protective coating is applied on the printing ink layer) and both the protective coatings are gloss type or both are matte type, however having different compositions are given below in Table 2.
Table 2

10
Abbreviations
(HSL)
(PAPER)
(OBC) 15 (ADH)
(MET)
(MBC)
(INK)
(PGC) 20 (PMC)
(FPG)
(FPM)
(SPG)
(SPM) 25 (FPGS, SPGS)
(FPMS, SPMS)
(FPGD, SPGD)
(FPMD, SPMD)

Structure
Example 8 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPGS / INK/ SPGS
Example 9 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPGD / INK/ SPGD
Example 10 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPMS / INK/ SPMS
Example 11 HSL/ PAPER/ OBC/ ADH/ MET/ MBC / FPMD / INK/ SPMD
heat seal Lacquer
paper substrate
oxygen barrier coating
adhesive layer
metallised layer
moisture barrier coating
printing ink layer
protective gloss coating
protective matte coating
first protective gloss coating layer
first protective matte coating layer
second protective gloss coating layer
second protective matte coating layer
FPG and SPG compositions are same
FPM and SPM compositions are same
FPG and SPG compositions are different
FPM and SPM compositions are different
[14]

Property Evaluation results for Examples 1 to 7
Water vapour transmission rate (WVTR) of the plastic free oxygen and moisture barrier coated metallised paper based structures were measured at 90% relative humidity and at a temperature of 37.8 °C using Mocon Permatran-W, Model 3/34G. 5
Oxygen transmission rate (OTR) of the plastic free oxygen and moisture barrier coated metallised paper based structures were measured at 0% relative humidity and at a temperature of 23 °C using Mocon Ox-Tran, Model 2/22H.
10 INK printability on the moisture barrier coating (MBC), or the first protective coating (FPC) in the plastic free oxygen and moisture barrier coated metallised paper based structures were visually judged.
Tear resistance of the plastic free oxygen and moisture barrier coated metallised 15 paper based structures were measured using PRESTO TEARING TESTER.
The evaluation results for the plastic free oxygen and moisture barrier coated metallised paper based structures of Examples 1 to 7 have been provided in Table 3. 20
Table 3

WVTR (g/m2/24 hours) OTR (cc/m2/24 hours) Printability* Tear resistance (Grams)
Example 1 2.77 3.00 5 48
Example 2 3.18 3.08 5 51
Example 3 2.87 2.78 5 53
Example 4 2.55 2.50 5 47
Example 5 2.80 3.45 5 52
Example 6 2.60 3.15 5 49
Example 7 2.70 2.65 5 50
*Rating: 1=poor; 5=Excellent
25
[15]

Property Evaluation results for Examples 8 to 11
The evaluation results for the plastic free oxygen and moisture barrier coated metallised paper based structures of Examples 8 to 11 have been provided in Table 4. 5
Table 4

WVTR (g/m2/24 hours) OTR (cc/m2/24 hours) Printability* Tear resistance (Grams)
Example 8 2.55 2.65 5 52
Example 9 2.52 2.60 5 51
Example 10 2.67 3.10 5 49
Example 11 2.62 2.85 5 54
*Rating: 1=poor; 5=Excellent
10 Advantages
The plastic free oxygen and moisture barrier coated metallised paper based structures of the present invention has several advantages.
• Excellent water vapour and oxygen barrier properties
• Environment friendly as the structures of the present invention are
15 biodegradable
• Improved printability
• Excellent tear resistance
• Cost effective because it does not use any foils
• Ease of production because the handling is better than foil
20
Applications
The plastic free oxygen and moisture barrier coated metallised paper based structure of the present invention is primarily intended for packaging applications for packaging of items such as food, beverage, cosmetics, pharmaceuticals and other medical 25 supplied items, chemical products, electronic parts, where permeation of water vapour and oxygen through the surface of the packaging material degrades the quality of the products therein.
However a person skilled in the art can find other appropriate areas to use the plastic
[16]

free oxygen and moisture barrier coated metallised paper based structure of the present invention.
Although the present disclosure is described in terms of certain preferred embodiments and examples, other embodiments and examples will be apparent to those of ordinary skill in the art, given the benefit of this disclosure, including embodiments and examples that do not provide all of the benefits and features set forth herein, which are also within the scope of this disclosure. It is to be understood that other embodiments may be utilized, without departing from the true spirit and scope of the present invention being indicated by the following claims.

We claim:

A plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article comprising:
a. a paper substrate (PAPER) having a first planar surface and a second planar
surface,
b. a layer of oxygen barrier coating (OBC) applied on the first planar surface of
PAPER,
c. a layer of adhesive (ADH) applied on the OBC,
d. a metallised (MET) layer deposited on the ADH layer,
e. a moisture barrier coating (MBC) layer applied on the MET layer,
f. a printing ink layer (INK) formed on the MBC layer; and
g. a heat seal lacquer (HSL) applied to the second planar surface of the
PAPER.
A plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article comprising:
a. a paper substrate (PAPER) having a first planar surface and a second planar
surface,
b. a layer of oxygen barrier coating (OBC) applied on the first planar surface of
PAPER,
c. a layer of adhesive (ADH) applied on the OBC,
d. a metallised (MET) layer deposited on the ADH layer,
e. a moisture barrier coating (MBC) layer applied on the MET layer,
f. a printing ink layer (INK) formed on the MBC layer,
g. a protective gloss coating (PGC) layer or a protective matte coating (PMC)
layer applied on the INK layer; and
h. a heat seal lacquer (HSL) applied to the second planar surface of the PAPER.
A plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article comprising:

a. a paper substrate (PAPER) having a first planar surface and a second planar
surface,
b. a layer of oxygen barrier coating (OBC) applied on the first planar surface of
PAPER,
c. a layer of adhesive (ADH) applied on the OBC,
d. a metallised (MET) layer deposited on the ADH layer,
e. a moisture barrier coating (MBC) layer applied on the MET layer,
f. a first protective coating (FPC) layer applied on the MBC layer
g. a printing ink layer (INK) formed on the FPC layer,
h. a second protective coating (SPC) layer provided above the INK layer; and i. a heat seal lacquer (HSL) applied to the second planar surface of the PAPER.
The plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article according to claim 3, wherein the first protective coating (FPC) layer, and the second protective coating (SPC) layer may be of same composition or different compositions; and wherein the first protective coating (FPC) layer is selected from a gloss coating or a matte coating, and the second protective coating (SPC) layer is selected from a gloss coating or a matte coating.
The plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article according to any of claims 1 to 3, wherein, the areal density of the PAPER is about 25 to 100 gsm, preferably about 50 to 75 gsm, the OBC is applied in an amount of about 2.0 to 5.0 gsm, preferably about 4.0 gsm, the ADH is applied in an amount of about 2.0 to 4.0 gsm, preferably about 3.0 gsm, the MET is deposited with an optical density (OD) of about 1.0 -3.0, preferably about 2.0, the MBC is applied in an amount of about 2.0 to 4.0 gsm, preferably about 3.0 gsm; and the HSL is applied in an amount of about 2.0 to 4.0 gsm, preferably about 3.0 gsm.
;. The plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article according to any of claims 2 and 3, wherein the

protective coatings are applied in an amount of about 0.5 to 2.5 gsm, preferably 1.0 gsm.
The plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article according to any one of the preceding claims has a calculated water vapour transmission rate (WVTR) of about 2.0 to 3.0 g/m2/24 hours; and a calculated oxygen transmission rate (OTR) of about 3.0 to 4.0 cc/m2/24 hours.
A method of forming a plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article comprising:
a. supplying a paper substrate (PAPER) having a first planar surface and a
second planar surface,
b. applying a layer of oxygen barrier coating (OBC) on the first planar surface of
PAPER,
c. applying a layer of adhesive (ADH) on the OBC,
d. depositing a metallised (MET) layer on the ADH layer,
e. applying a moisture barrier coating (MBC) layer on the MET layer,
f. printing an image (INK) on the MBC layer,
g. applying a protective gloss coating (PGC) or a protective matte coating
(PMC) on the INK layer; and
h. applying a heat seal lacquer (HSL) to the second planar surface of the PAPER.
A method of forming a plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article comprising:
a. supplying a paper substrate (PAPER) having a first planar surface and a
second planar surface,
b. applying a layer of oxygen barrier coating (OBC) on the first planar surface of
PAPER,
c. applying a layer of adhesive (ADH) on the OBC,
d. depositing a metallised (MET) layer on the ADH layer,
e. applying a moisture barrier coating (MBC) layer on the MET layer,

f. applying a first protective coating (FPC) on the MBC layer
g. printing an image (INK) on the FPC layer,
h. applying a second protective coating (SPC) layer above the INK layer; and i. applying a heat seal lacquer (HSL) to the second planar surface of the PAPER.
10. The method of forming a plastic free oxygen and moisture barrier coated metallised paper based structure for a packaging article of claims 8 or 9, wherein the metallised (MET) layer is deposited by metal deposition methods selected from transfer metallisation, vacuum metallisation, preferably deposited by transfer metallisation method.