Title of Invention	A MULTILAYER THERMOFORMABLE PACKAGING LAMINATE
Abstract	A multilayer thermoformable packaging laminate comprising a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; a cost of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate; a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate.

Title of Invention

A MULTILAYER THERMOFORMABLE PACKAGING LAMINATE

Abstract

A multilayer thermoformable packaging laminate comprising a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; a cost of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate; a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate.

Full Text	FORM-2 THE PATENTS ACT, 1970 (39 of 1970) & THE PATENTS RULES, 2003 COMPLETE (See section 10 and rule 13) A MULTILAYER THERMOFORMABLE PACKAGING LAMINATE BILCARE LIMTIED, an Indian Company of 1028, Shiroli, Rajgurunagar (Taluka Khed), Pune 411 505, Maharashtra, India 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 multi-layer film laminates. Particularly, the present invention relates to multi-layer film laminates suitable for use in the pharmaceutical packaging industry. Background of the invention Today, a significant fraction of healthcare products are packed in blisters. Amongst many other advantages, blister packaging offers convenience in terms of portability and also helps to protect the packaged drug over a longer shelf life. One way to form blisters is by thermoforming a rigid polymer film. Blister packaging has proven to be a highly effective and successful packaging form for the pharmaceutical industry. Not only does it instill confidence regarding the quality and purity of a product, it also provides the manufacturer with a surface upon which information may be provided to the consumer. Counterfeiting is a severe problem for all industries including the pharmaceutical industry. Legitimate businesses are losing millions due to counterfeit activity. The International chamber of commerce estimates that US $ 900 Billion are lost by businesses worldwide. This translates to 10-30 % of the sales being lost to counterfeiters, forgers and duplicators. In some countries the figure in percentage is much higher. Counterfeiting is the fastest growing crime in the world. Studies show that consumers would prefer to buy products that are in tamper evident authenticated packaging so as to reduce the chance of buying imitation products. However, with the growing counterfeiting problem, that the pharmaceutical industry has to tackle (research by the World Health Organization shows that approximately 5% of the world's medicines are counterfeit, and in some areas this percentage can be as high as 50%), leading brands are prone to be attacked by unscrupulous individuals. It is the responsibility of the manufacturer or brand owner to ensure that a genuine unadulterated product reaches the consumer. Blister packaging, which is prone to counterfeiting, appears to be losing its 'sheen'. It can be a viable proposition if it evolves such that it is impossible for a counterfeiter to duplicate. Objects of the invention The present invention therefore has as an object a packaging film which will help against counterfeiting. Another object of this invention is to provide a packaging film which will act as a protective authentication and by which a lay person can easily indentify the product at a display counter and distinguish it from a fake. Summary of the invention According to this invention there is provided a multilayer thermoformable packaging laminate comprising (i)a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns, (ii) a coat of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate, (iii) a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and (iv) a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate. Typically, the polymeric substrate consists of at least one polymeric resin selected from a group of resins consisting of polyvinyl chloride (PVC), Polypropylene (PP), Polyethylene (PE), polyethylene terepthalate (PET) and co-polymers of theses resins. Typically, the polymeric substrate is transparent, translucent or coloured. In one embodiment of the invention, the substrate is colored and coloring of the polymeric substrate is done by using a colored lacquer or a pigment. Preferabely, the base is multilayered and is laminated to the substrate after the patterns is embossed. Preferably the sulphide of metal is (ZnS). Preferably, the metal oxide is silicon (SiOx and SiOx.nNx) which provides transparent coating on the surface of the polymer laminate and which can provide better adhesion for the nonuniform embossed differential grating pattern on the substrate.] Typically, the base is multilayered, having a plurality of polymeric layers bonded together, by adhesive bonding, thermal bonding or co-extrusion. In one embodiment, the substrate is multilayered having at least one transparent layer and at least one colored layer. In another embodiment, the substrate is multilayered, consisting of polymeric layers adhesive bonded to each other, the adhesive between the layers being pigmented. In accordance with this invention, the metal used for sulphide or oxide coating is at least 99% pure metal selected from zinc and silicon. In yet another embodiment, the film includes at least one colored or colorless lacquer layer having thickness of 0.5 to 8 microns applied between the substrate and the coat, between the coat and the metal sulphide or metal oxide layer or above the metal sulphide or metal oxide layer. The laminate may include an optional polymeric layer 0.5 to 250 microns thick. In yet another embodiment, the substrate or base includes at least one polymeric layer selected from a group consisting of a moisture barrier layer, an oxygen barrier layer, a gas barrier, and a vapor barrier layer, said optional layer being provided operably within the substrate, on the substrate and below the coat, or below the substrate, or within the base. Typically, the embossed pattern is a diamond pattern, a broken glass pattern, a square pattern, a honey comb pattern, a triangular pattern, a wavy line pattern, a star burst pattern; a circular pattern a striation pattern or a combination of patterns and includes text matter. In accordance with another aspect of this invention, there is provided a process for preparation of a multilayer thermoformable packaging laminate comprising the following steps: (i) applying a coat of an ester acrylic based primer, upto a thickness in the range of 0.1 to 1 micron upon a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; (ii)partially drying the said primer coat; (iii) depositing a metal compound selected from sulphide or metal oxide on the said partially dried primer coat to form a metal sulphide or metal oxide layer of thickness between .001 to 0.3 microns; and (iv) embossing the metalized layer with a shim to form an embossed pattern on the metal compound layer and to make the thickness of the metal compound layer non uniform; (v) laminating other side of the substrate with a polymeric base of thickness 50 to 1000 microns. Typically the metal sulphide or metal oxide layer is deposited on the primer coat by vacuum deposition. In accordance with another aspect of the process of the invention the process includes a step of applying a lacquer coat, typically a colored lacquer coat either on the film or on the primer coat. The multilayer thermoformable non uniform embossed film may be coated with a suitable adhesive selected from the group of Polyurethanes, Waterborne acrylic dispersion-type coatings, UV-curable formulations, and unsaturated polyesters (peroxide cured). Detailed description of the invention The present invention provides a multilayered thermoformable transparent non uniform metal sulphide or metal oxide coated polymeric laminate. A multilayer thermoformable laminate of thickness between 10 - 150 microns comprising a non uniform embossed metal sulphide or metal oxide coated polymeric film having first and second surfaces and at least one rigid thermoformable polymeric base of thickness between 50 - 1000 microns laminated to the non uniform embossed metallized film. The present invention is now described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention. In the case of any inconsistencies, the present disclosure, including any definitions therein will prevail. The term "coating" as used in the present text includes applying, layering and pressing or deposition of metal by vacuum evaporation process. The expression "a multi-layer laminate" as used in the present invention includes a multi-layer laminate comprising a thermoformable non uniform embossed metal sulphide or metal oxide coated polymer based laminate. The expression "a multi-layer laminate" as used in the present invention also includes a laminate comprising a thermoformable non uniform embossed metallised film laminated with at least one rigid thermoformable polymer with the help of a suitable polymeric adhesive. The thickness of individual layers in the multi-layer laminate can vary depending on specific intended use and also on the ease of operation. Also, the multi-layer laminate may additionally comprise additional layers of polymer, resin or other substances, if desired. Before coating adhesive to the first surface of the rigid polymeric substrate, the rigid thermoformable polymeric film can be pretreated, to impart uniformity or improve the adhesion of the coated material. In a typical process for preparation of a multi-layer laminate according to the present invention, the non uniform embossed metallised film of thickness between 10-150 microns having first and second surfaces is first prepared. The first surface of the substrate is coated with metal sulphide or metal oxide by vacuum evaporation/deposition technique. The non uniform embossed metal sulphide or metal oxide coated film is initially coated with suitable primer for assuring uniform coating and proper adhesion of the metal oxide/sulphide on the polymeric film during vacuum evaporation. The metallized thermoformable film is then subjected to non uniform embossing with a desired art work and design. Optionally coloring of the metallized film can be done to get a coloured metallized non uniform embossed metallized film. To achieve coloration of the metallized film, the former film is coated with a desired coloured lacquer of thickness 0.5 to 1.5 microns. The application of the colored lacquer can be done before the metallization process or after the metallization process of the polymeric film. Then, the coloured/ without colour metallized polymeric film is subjected to non uniform embossing with a predetermined art work design. The other side of this film is coated with a suitable adhesive of thickness between 0.5-8 microns and laminated with a rigid polymeric base having thickness between 50 to 1000 micron. The adhesive helps to fix the coloured/ without coloured metallized non uniform embossed metallized film to the rigid polymeric base on the second surface of the non uniform embossed metallized polymeric film efficiently. A wide variety of adhesives can be advantageously used according to the present invention. Preferably, the adhesive comprises a polymeric substance capable of undergoing polymerization at higher temperatures. The adhesive coat can be applied by several methods typically known to a person skilled in the art and includes coating and spraying. The wet adhesive coat is then pressed with the desired polymer film. If desired, before applying the colored/ without coloured non uniform embossed metallized film, the adhesive coat is partially dried. Such partial drying at elevated temperature removes volatile components. Once the desired polymer film is applied on the adhesive coat, say by pressing, the laminate may further be subjected to heat treatment. When the adhesive coat comprises a polymerizable substance, the curing of this polymerizable substance occurs through further polymerization, thereby imparting further adhesive strength. However, the post-heat treatment is optional and entirely depends on several parameters such as the nature of the individual constituents and the final properties desired. A wide variety of polymer films can be used for the thermoformable non uniform embossed metallized film according to the present invention. Typical non-limiting examples of such film include metallized color film such as a metallized polyvinyl chloride (PVC) film or high density polyethylene (HDPE) or low density polyethylene (LDPE) or polypropylene (PP) or amorphous polyethylene terephthalate (APET) and co-polymer of PET with glycol (PETg). The colored film may be obtained commercially or prepared by metallizing a desired polymer film with a suitable metal like aluminum, silver, gold, through known a metallization process, such as for example, vacuum deposition. Thus the obtained multi-layer laminate having a colored film which is metallized and embossed with a pre determined pattern and having non uniform thickness is laminated with the rigid thermoformable polymeric base .. As mentioned earlier, the thickness of individual layers, including those of the rigid polymeric base, adhesive coat and colored metallized non uniform embossed metallized film can be selected from within a wide range, depending on the specific intended use and/or operational ease. The multi-layer laminates according to the present invention have excellent bursting strength, barrier properties and deformation resistance. Advantageously, the laminates according to the present invention have high abrasion resistance and also can withstand thermoforming processes without any damage to the non uniform embossed metallized design during the process of thermoforming the film in to blisters packaging. Further, the multilayered thermofromable non uniform embossed metallized film can act against counterfeiting effectively. From the foregoing description, it will thus be evident that the present invention provides novel multi-layer laminates comprising thermoformable ed non uniform embossed metallized layered polymeric films and at least one rigid polymeric base and a method for their preparation. While certain embodiments of the invention have been described, these embodiments have been presented by way of examples only, and are not intended to limit the scope of the inventions. Variations or modifications to the design and construction of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the invention. The invention will now be described with reference to the accompanying examples Example 1 A 35 micron pharmaceutical grade PVC film devoid of plasticizer having 600 mm width was subjected to an unwinder of a gravure coating machine. Ester -acrylic based primer from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using the gravure roller to the PVC film and extra primer was removed by doctoring process. Deposition of this primer had a thickness of 0.8 microns. Then this film was allowed to travel through on-line ovens via a conveyer. The oven temperature was set at a temperature of 75° C and the speed of 30 m/min for drying the primer on the film was maintained. The drying of the primer on the film was confirmed by non tackiness and by non blocking of the rewinding at the re winder roller. The two layer film formed above was then transferred to a vacuum deposition machine. This machine had an in situ plasma device and was fitted with an evaporation boat in which the material to be deposited was placed. The primer coated surface of the laminated film was first treated with plasma and thereafter was deposited with zinc silphide having 99.99% purity. Thickness of this deposited layer was 0.025 microns. The thickness was achieved by adjusting the speed, height of the gun and the vacuum level. This three layer film was exposed to a differential embossing grating process. A custom built machine was used for the embossing process. The three layered film was placed on an unwinder of this custom made machine, the film was passed through the roller having temperature of 130 to 150° C by which the film was softened. A diamond pattern shim was pressed on the metallized side of the film to create a diffraction grating embossed effect on the film. The shim made for the above purpose was cut with a diamond pattern by using a computerized laser cutting mechanism to avoid duplication of the pattern by any one else. The other side of this film was then laminated to a 250 micron rigid PVC base by applying an adhesive between 0.5 to 8 microns through the gravure lamination technique. Blisters packs were formed from this laminate by the thermoforming process which showed excellent thermoforming performance and showed the fine diamond non uniform embossed metallized pattern even after the thermoforming process. Specification of the film was as follows: Total thickness 287 micron Adhesion of embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength Tensile strength - Longitudinal -Transverse Elongation - Longitudinal - Transverse Heat seal strength WVTR of the blister 955 g 13.5 kg/cm2 13.7Kg/cm2 5.9% 5.8% 0.65 kg/cm 8 g/m2/day Example 2 A film was produced as per example 1 except thickness of the PVC film was 50 microns and pattern used for embossing was a rain-bow pattern. The three layer film was laminated to. a 250 micron rigid PVC base., \|This laminate demonstrated the following properties Total thickness 304 micron Adhesion of embossed pattern with scotch tape test: passes Thermoforming performance Impact strength Tensile strength - Longitudinal -Transverse Elongation - Longitudinal - Transverse Heat seal strength Excellent >950g 14.05 kg/cm2 14.13 Kg/cm2 6.2 % 6.15% 0.65 kg/cm2 Example 3 A film was produced as per example 1 except thickness of the PVC film was 100 microns and pattern used for embossing was fine grains pattern. The resulting multilayer film substrate was then laminated to a thermoformable, pharmaceutical grade PVC film of 250 microns devoid of plasticizer, using dry adhesion technology. Solvent based polyurethane adhesive of 4 microns was applied to the latter PVC mono layer film by using gravure coating process. The adhesive suspension that was applied had a viscosity of 24 sec, and was dried at 75° at a machine speed of 30 m/min. The multilayer film demonstrated the following properties. Total thickness 354 micron Differentially grated laminated film thickness 100 micron Adhesive coat 4 microns Adhesion to substrate & differentially grated laminated film 200 gm/cm Adhesion of differentially grated laminated with scotch tape test: passes Thermoforming performance Excellent Impact strength>950 g Tensile strength - Longitudinal 20.85 kg/cm -Transverse 20.6 kg/cm Elongation - Longitudinal 6.6 % - Transverse 6.7 % Example 4 A film was produced as per the example 1 except thickness of the PVC film which was 120 microns and pattern used for embossing was square pattern. The resulting multilayer film substrate was then laminated to a base consisting of three PVC films of thickness 300 microns bounded to each other by using polyurethane based adhesive of thickness 4 microns via gravure coating technique, using dry adhesion technology as per example 3. The multilayer film demonstrated the following properties Total thickness 1050 micron Differentially grated laminated film thickness 120 micron Adhesive coat 12 microns Adhesion to substrate & differentially grated laminated film 200 gm/cm Adhesion of differentially grated laminated with scotch tape test: passes Thermoforming performance not possible Impact strength > 900 g Tensile strength - Longitudinal 50.66 kg/cm -Transverse 45.44 kg/cm2 Elongation - Longitudinal 8.5 % - Transverse 7.6 % Example 5 A film was produced as per the example 2 in which a blue coloured pigmented 50 micron PVC film with text used for embossing with a flower like pattern. The resulting multilayered laminated demonstrated following properties: Total thickness 304 micron Differentially grated laminated film thickness 50 micron Adhesive coat 4 microns Adhesion to substrate & differentially grated laminated film 200 gm/cm Adhesion of differentially grated laminated with scotch tape test: passes Thermoforming performance Excellent Impact strength > 950 g Tensile strength - Longitudinal -Transverse Elongation - Longitudinal - Transverse 14.05 kg/cm2 14.13 kg/cm2 6.2 % 6.15% Example 6 A film was produced as per example 5 in which a blue coloured pigmented PVC film of thickness 75 microns and pattern used for embossing was broken glass pattern. The resulting multilayered laminated demonstrated the following properties: Total thickness blue tinted differentially grated laminated film thickness Adhesive coat Adhesion to substrate & differentially grated laminated film 330 micron 75 micron 5 microns 200 gm/cm Adhesion of differentially grated laminated with scotch tape test: passes Thermoforming performance Impact strength Tensile strength - Longitudinal -Transverse Elongation - Longitudinal - Transverse Excellent >950g 15.5 kg/cm2 15.2 kg/cm2 7.2 % 7.15% Example 7 A film was produced as per example 1 except that the thickness of the PVC film was 50 microns and the pattern used for embossing was a square pattern. The resulting multilayered film was laminated with a blue coloured tinted 250 micron thick pharmaceutical grade, thermoformable rigid PVC base devoid of plasticizer with the help of gravure coating process using a polyurethane based adhesive of thickness 4 microns . The lamination was effected at 75°C. The resulting film demonstrated the following properties Total thickness 304 micron Differentially grated laminated film thickness 50 micron Adhesive coat 4 microns Colour Blue Adhesion to substrate & differentially grated laminated film 200 gm/cm Adhesion of differentially grated laminated with scotch tape test: passes Thermoforming performance Excellent Impact strength > 950 g Tensile strength -Longitudinal 14.1 kg/cm -Transverse 14.0 kg/cm2 Elongation - Longitudinal 6.2 % - Transverse 6.15 % Example 8 A 35 micron thick thermoformable pharmaceutical grade gold pigmented PVC film with zinc sulphide metallization layer thickness of .033 microns was made to undergo differential grating embossing procedure as per example 1 and further was laminated with a thermoformable pharmaceutical grade PVC film of thickness 300 microns with the help of polyurethane based adhesive coat via gravure coating process. The resultant film demonstrated the following properties Total thickness 340 micron Gold tinted differentially grated laminated film thickness 35 micron Adhesive coat 5 microns Adhesion to substrate & differentially grated laminated film 200 gm/cm Adhesion of differentially grated laminated with scotch tape test: passes Thermoforming performance Excellent Impact strength > 950 g Tensile strength - Longitudinal 15.1 kg/cm2 -Transverse 15.0 kg/cm2 Elongation - Longitudinal 6.2% - Transverse 6.1% Example 9 A laminate was produced as per example 1 except that the polymeric film was used from the class of co-polymer of polyethylene terepthalate and glycol (PETg) film having 50 micron thickness and the pattern used for embossing was a rain-bow pattern. The resultant laminate demonstrated the following properties Total thickness 300 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength >950 g Tensile strength -Longitudinal 12kg/cm2 -Transverse 12.1 Kg/cm2 Elongation - Longitudinal 5.5% - Transverse 5.1% Example 10 A laminate was produced as per example 1 except that the polymeric film was used from the class of co-polymer of polyethylene terepthalate and glycol (PETg) film having thickness 100 microns and pattern used for embossing was diamond pattern. The resultant laminate demonstrated the following properties Total thickness 354 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength 950 g Tensile strength - Longitudinal 12.5 kg/cm2 -Transverse 12.4 Kg/cm2 Elongation - Longitudinal 5.9 % - Transverse 5.8 % Heat seal strength 0.65 kg/cm Example 11 A laminate was produced as per example 1 except that the polymeric film was used from the class of co-polymer of polyethylene terepthalate and glycol (PETg) film of thickness 12 microns and pattern used for embossing was a square pattern. The laminate demonstrated the following properties Total thickness 267 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance excellent Impact strength >950 g Tensile strength - Longitudinal 6.5 kg/cm Elongation -Transverse 5.75 kg/cm2 Longitudinal 5.5 % Transverse 5.1 % Example 14 A laminate was produced as per example 1 except that a cast polypropylene film was used as a base having thickness of 300 microns and pattern used for embossing was a diamond pattern. The three layer laminate demonstrated the following properties Total thickness 335 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength >350 g Tensile strength - Longitudinal 2.36 kg/cm2 -Transverse 2.2 Kg/cm2 Elongation - Longitudinal 11.2% - Transverse 11% Example 15 A film was produced as per example 1 except that the thickness of the PVC film was 35 microns and the pattern used was a broken glass pattern. The three layer film was further laminated with a 300 micron thick cast polypropylene film by using polyurethane based adhesive of thickness 5 microns with the help of gravure coating process. The resulting laminate demonstrated the following properties Total thickness 340 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Excellent >953g 17.39 kg/cm2 16.78 Kg/cm2 6.4% 6.5% Thermoforming performance Impact strength Tensile strength - Longitudinal -Transverse Elongation - Longitudinal -Transverse Example 16 A laminate was produced as per example 1 except thickness of the PVC film was 100 microns and pattern used was a broken glass pattern. The three layer film was further laminated with a 250 micron thick co-polymer of polyethylene terepthalate and glycol (PETg) film base using a polyurethane based adhesive with the help of gravure coating process. The resulting film demonstrated the following properties Total thickness 360 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Excellent >953g 17.39 kg/cm2 16.78 Kg/cm2 6.4% 6.5% Thermoforming performance Impact strength Tensile strength - Longitudinal -Transverse Elongation - Longitudinal -Transverse Example 17 A 50 micron pharmaceutical grade PVC film roll devoid of plasticizer having 600 mm width was subjected to un winder of gravure coating machine . A coloured lacquer was then applied to this film having thickness of 4 micron with the help of gravure technology then after second pass the Ester -acrylic based special primer from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using gravure roller to this PVC film and extra primer was removed by doctoring process. Deposition of this primer had a thickness of 0.8 microns. Then this film was allowed to travel through on line ovens via a conveyer at a temperature of 75° C at the speed of 30 m/min. The drying of the film was ensured by non tacky and non blocking rewinding at the rewinder roller. Thus the two layer laminate film formed above was then transferred to a vacuum deposition machine. This machine had an in situ plasma device and was fitted with an evaporating boat in which the material to be deposited was placed. The primer coated surface of above laminated film was first treated with plasma and thereafter deposited with a zinc sulphide layer having 99.99% purity, thickness of this deposited layer was 0.020 microns. The thickness was achieved by adjusting the speed, height of gun and vacuum level. Further, this three layer laminated film was exposed to differential embossing grating process. Custom made machine was used for embossing process. The three layered laminated film was then placed on un winder of this custom made machine, the film then was passed through a roller having temperature of 130 to 150° C by which the film was getting soften, then diamond pattern shim was pressed on the metallized side of the laminate to create a diffraction grating on the film. The shim made for the above purpose was cut with a diamond pattern by using computerized laser cutting mechanism to avoid duplication of the pattern by any one else. Then this film was laminated to 200 micron PVC base devoid of plasticizer and having a vinyl chloride monomer concentration of less than 1 ppm and global migration less than 60 ppm. Blister packs were formed from this film by thermoforming process which showed excellent thermoforming performance and showed a fine diamond non uniform embossed metallized pattern even after the thermoforming process. This laminate exhibited the following properties, Total thickness 256 microns Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength 953 g Tensile strength -Longitudinal 5.11kg/cm2 -Transverse 4.88 Kg/cm2 Elongation - Longitudinal 5% - Transverse 4.8% Heat seal strength 0.65 kg/cm Example 18 A 50 micron pharmaceutical grade PVC film roll devoid of plasticizer having 600 mm width was subjected to the un winder of a gravure coating machine .Ester -acrylic based special primer from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using gravure roller to this PVC film and extra primer was removed by doctoring process. Deposition of this primer had thickness of 0.8 microns. Then this film was allowed to travel through in line ovens via a conveyer at a temperature of 75° C at a speed of 30 m/min. The drying of the film was ensured by non tacky and non blocking rewinding at rewinder roller. Colour lacquer was then applied to this film with the help of the gravure. Thus the three layer laminate film formed above was then transferred to a vacuum deposition machine. The primer coated surface of above laminated film was first treated with plasma and zinc sulphide having 99.99% purity, thickness of this deposited layer was 0.1 micron. The thickness was achieved by adjusting the speed, height of gun and vacuum level. Further, this three layer laminated film was exposed to differential embossing grating process. Custom made machine was used for the embossing process. The three layered laminated film was then placed on un winder of this custom made machine, the film was passed through a roller having temperature of 130 to 150° C by which the film was softened, then a diamond pattern shim was pressed on the metallized side of the laminate to create a diamond pattern on the film. Then this film was laminated as per example 17. Blister packs were formed from this film by a thermoforming process which showed excellent thermoforming performance and showed the fine diamond non uniform embossed metallized pattern even after thermoforming process. The laminate exhibited the following properties, Total thickness 256 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength 953 g Tensile strength - Longitudinal 5.11 kg/cm2 -Transverse 4.88 Kg/cm2 Elongation - Longitudinal 5% - Transverse 4.8% Heat seal strength 0.65 kg/cm Example 19 A 50 micron pharmaceutical grade PVC film roll devoid of plasticizer having 600 mm width was subjected to a un winder of gravure coating machine. Ester -acrylic based special primer with blue pigment in it from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using gravure roller to this PVC film and extra primer was removed by doctoring process. Deposition of this primer had a thickness of 0.8 microns. This film was allowed to travel through in line ovens via a conveyer at a temperature of 75° C at the speed of 30 m/min. The drying of the film was ensured by non tacky and non blocking rewinding at rewinder roller. This two layer laminate film formed above was deposited with a zinc sulphide layer of 0.025 microns as per the previous examples. The thickness was achieved by adjusting the speed, height of gun and vacuum level. Further, this three layer film was exposed to a differential embossing grating process. Custom made machine was used for embossing process. The three layered laminated film was then placed on un winder of this custom made machine, the film then was passed through a roller having temperature of 130 to 150° C by which the film was softened, then a diamond pattern shim was pressed on the metallized side of film to create a diamond pattern diffraction grating on the film as per the previous examples. The shim made for the above purpose was cut with a diamond pattern by using computerized laser cutting mechanism to avoid duplication of the pattern by any one else. Then this film was laminated as per example 17 to a base. blister packs were formed from this film by thermoforming process which showed excellent thermoforming performance and showed the fine diamond non uniform embossed metallized pattern even after the thermoforming process, the laminate exhibited the following properties, Total thickness 256 micron Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Excellent Impact strength 953 g Tensile strength - Longitudinal 5.11kg/cm2 -Transverse 4.88 Kg/cm2 Elongation - Longitudinal 5% - Transverse 4.8% Heat seal strength 0.65 kg/cm Example 20 Laminate made as per example 1 was coated with a PVDC coating on the other side of the diffraction grating with help of dispersion coating techniques to enhance the barrier properties of the laminate . the laminate exhibited the following properties, Total thickness 280 micron Excellent 953 g 5.11 kg/cm2 4.88 Kg/cm2 5% 4.8% 0.65 kg/cm 0.1 gm/cm2/day Adhesion of non uniform embossed pattern with scotch tape test: passes Thermoforming performance Impact strength Tensile strength - Longitudinal -Transverse Elongation - Longitudinal - Transverse Heat seal strength WVTR We Claim: [1] A multilayer thermoformable packaging laminate comprising (i)a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns, (ii) a coat of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate, (iii) a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and (iv) a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate. [2] A multilayer thermoformable packaging laminate as claimed in claim 1, in which , the polymeric substrate consists of at least one polymeric resin selected from a group of resins consisting of polyvinyl chloride (PVC), Polypropylene (PP), Polyethylene (PE), polyethylene terepthalate (PET) and co-polymers of theses resins. [3] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the polymeric substrate is transparent, translucent or coloured. [4] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate is colored and coloring of the polymeric substrate is done by using a colored lacquer or a pigment. [5] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the base is multilayered and is laminated to the substrate after the pattern is embossed. [6] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the sulphide of metal is (ZnS). [7] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the metal oxide is silicon (SiOx and SiOx.nNn). [8] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the base is multilayered, having a plurality of polymeric layers bonded together, by adhesive bonding, thermal bonding or co-extrusion. [9] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate is multilayered having at least one transparent layer and at least one colored layer. [10] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate is multilayered, consisting of polymeric layers adhesive bonded to each other, the adhesive between the layers being pigmented. [11] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the metal used for sulphide or oxide coating is at least 99% pure metal selected from zinc and silicon. [12] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the film includes at least one colored or colorless lacquer layer having thickness of 0.5 to 8 microns applied between the substrate and the coat, between the coat and the metal sulphide or metal oxide layer or above the metal sulphide or metal oxide layer. [13] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate or base includes at least one polymeric layer selected from a group consisting of a moisture barrier layer, an oxygen barrier layer, a gas barrier, and a vapor barrier layer, said layer being provided operably within the substrate, on the substrate and below the coat, or below the substrate, or within the base. [14] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the embossed pattern is a diamond pattern, a broken glass pattern, a square pattern, a honey comb pattern, a triangular pattern, a wavy line pattern, a star burst pattern; a circular pattern a striation pattern or a combination of patterns and includes text matter. [15] A process for preparation of a multilayer thermoformable packaging laminate as claimed in claim 1 ,comprising the following steps: (i) applying a coat of an ester acrylic based primer, upto a thickness in the range of 0.1 to 1 micron upon a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; (ii) partially drying the said primer coat; (iii) depositing a metal compound selected from sulphide or metal oxide on the said partially dried primer coat to form a metal sulphide or metal oxide layer of thickness between .001 to 0.3 microns;and (iv) embossing the metalized layer with a shim to form an embossed pattern on the metal compound layer and to make the thickness of the metal compound layer non uniform; (v) laminating other side of the substrate with a polymeric base of thickness 50 to 1000 microns. [16] A process as claimed in claim 15, in which the metal sulphide or metal oxide layer is deposited on the primer coat by vacuum deposition. [17] A process as claimed in claim 16, which includes a step of applying a lacquer coat, typically a colored lacquer coat either on the film or on the primer coat. ABSTRACT A multilayer thermoformable packaging laminate comprising a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; a coat of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate; a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate.

Full Text

FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE
(See section 10 and rule 13)
A MULTILAYER THERMOFORMABLE PACKAGING LAMINATE
BILCARE LIMTIED,
an Indian Company
of 1028, Shiroli, Rajgurunagar (Taluka Khed), Pune 411 505,
Maharashtra, India
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 multi-layer film laminates. Particularly, the present invention relates to multi-layer film laminates suitable for use in the pharmaceutical packaging industry.
Background of the invention
Today, a significant fraction of healthcare products are packed in blisters. Amongst many other advantages, blister packaging offers convenience in terms of portability and also helps to protect the packaged drug over a longer shelf life. One way to form blisters is by thermoforming a rigid polymer film.
Blister packaging has proven to be a highly effective and successful packaging form for the pharmaceutical industry. Not only does it instill confidence regarding the quality and purity of a product, it also provides the manufacturer with a surface upon which information may be provided to the consumer.
Counterfeiting is a severe problem for all industries including the pharmaceutical industry. Legitimate businesses are losing millions due to counterfeit activity. The International chamber of commerce estimates that US $ 900 Billion are lost by businesses worldwide. This translates to 10-30 % of the sales being lost to counterfeiters, forgers and duplicators. In some countries the figure in percentage is much higher.
Counterfeiting is the fastest growing crime in the world. Studies show that consumers would prefer to buy products that are in tamper evident

authenticated packaging so as to reduce the chance of buying imitation products.
However, with the growing counterfeiting problem, that the pharmaceutical industry has to tackle (research by the World Health Organization shows that approximately 5% of the world's medicines are counterfeit, and in some areas this percentage can be as high as 50%), leading brands are prone to be attacked by unscrupulous individuals. It is the responsibility of the manufacturer or brand owner to ensure that a genuine unadulterated product reaches the consumer.
Blister packaging, which is prone to counterfeiting, appears to be losing its 'sheen'. It can be a viable proposition if it evolves such that it is impossible for a counterfeiter to duplicate.
Objects of the invention
The present invention therefore has as an object a packaging film which will help against counterfeiting. Another object of this invention is to provide a packaging film which will act as a protective authentication and by which a lay person can easily indentify the product at a display counter and distinguish it from a fake.
Summary of the invention
According to this invention there is provided a multilayer thermoformable packaging laminate comprising

(i)a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns,
(ii) a coat of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate,
(iii) a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and
(iv) a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate.
Typically, the polymeric substrate consists of at least one polymeric resin selected from a group of resins consisting of polyvinyl chloride (PVC), Polypropylene (PP), Polyethylene (PE), polyethylene terepthalate (PET) and co-polymers of theses resins.
Typically, the polymeric substrate is transparent, translucent or coloured.
In one embodiment of the invention, the substrate is colored and coloring of the polymeric substrate is done by using a colored lacquer or a pigment.
Preferabely, the base is multilayered and is laminated to the substrate after the patterns is embossed.
Preferably the sulphide of metal is (ZnS). Preferably, the metal oxide is silicon (SiOx and SiOx.nNx) which provides transparent coating on the surface of the

polymer laminate and which can provide better adhesion for the nonuniform embossed differential grating pattern on the substrate.]
Typically, the base is multilayered, having a plurality of polymeric layers bonded together, by adhesive bonding, thermal bonding or co-extrusion.
In one embodiment, the substrate is multilayered having at least one transparent layer and at least one colored layer.
In another embodiment, the substrate is multilayered, consisting of polymeric layers adhesive bonded to each other, the adhesive between the layers being pigmented.
In accordance with this invention, the metal used for sulphide or oxide coating is at least 99% pure metal selected from zinc and silicon.
In yet another embodiment, the film includes at least one colored or colorless lacquer layer having thickness of 0.5 to 8 microns applied between the substrate and the coat, between the coat and the metal sulphide or metal oxide layer or above the metal sulphide or metal oxide layer.
The laminate may include an optional polymeric layer 0.5 to 250 microns thick.
In yet another embodiment, the substrate or base includes at least one polymeric layer selected from a group consisting of a moisture barrier layer, an oxygen barrier layer, a gas barrier, and a vapor barrier layer, said optional layer being

provided operably within the substrate, on the substrate and below the coat, or below the substrate, or within the base.
Typically, the embossed pattern is a diamond pattern, a broken glass pattern, a square pattern, a honey comb pattern, a triangular pattern, a wavy line pattern, a star burst pattern; a circular pattern a striation pattern or a combination of patterns and includes text matter.
In accordance with another aspect of this invention, there is provided a process for preparation of a multilayer thermoformable packaging laminate comprising the following steps:
(i) applying a coat of an ester acrylic based primer, upto a thickness in the
range of 0.1 to 1 micron upon a pharmaceutical grade polymeric film
substrate, devoid of plasticizer, and having vinyl monomer content less than
60 ppm, said substrate, having thickness in the range of 10 to 150 microns;
(ii)partially drying the said primer coat;
(iii) depositing a metal compound selected from sulphide or metal oxide on
the said partially dried primer coat to form a metal sulphide or metal oxide
layer of thickness between .001 to 0.3 microns; and
(iv) embossing the metalized layer with a shim to form an embossed pattern
on the metal compound layer and to make the thickness of the metal
compound layer non uniform;
(v) laminating other side of the substrate with a polymeric base of thickness
50 to 1000 microns.
Typically the metal sulphide or metal oxide layer is deposited on the primer coat by vacuum deposition.

In accordance with another aspect of the process of the invention the process includes a step of applying a lacquer coat, typically a colored lacquer coat either on the film or on the primer coat.
The multilayer thermoformable non uniform embossed film may be coated with a suitable adhesive selected from the group of Polyurethanes, Waterborne acrylic dispersion-type coatings, UV-curable formulations, and unsaturated polyesters (peroxide cured).
Detailed description of the invention
The present invention provides a multilayered thermoformable transparent non uniform metal sulphide or metal oxide coated polymeric laminate. A multilayer thermoformable laminate of thickness between 10 - 150 microns comprising a non uniform embossed metal sulphide or metal oxide coated polymeric film having first and second surfaces and at least one rigid thermoformable polymeric base of thickness between 50 - 1000 microns laminated to the non uniform embossed metallized film.
The present invention is now described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention. In the case of any inconsistencies, the present disclosure, including any definitions therein will prevail.
The term "coating" as used in the present text includes applying, layering and pressing or deposition of metal by vacuum evaporation process.

The expression "a multi-layer laminate" as used in the present invention includes a multi-layer laminate comprising a thermoformable non uniform embossed metal sulphide or metal oxide coated polymer based laminate. The expression "a multi-layer laminate" as used in the present invention also includes a laminate comprising a thermoformable non uniform embossed metallised film laminated with at least one rigid thermoformable polymer with the help of a suitable polymeric adhesive.
The thickness of individual layers in the multi-layer laminate can vary depending on specific intended use and also on the ease of operation. Also, the multi-layer laminate may additionally comprise additional layers of polymer, resin or other substances, if desired.
Before coating adhesive to the first surface of the rigid polymeric substrate, the rigid thermoformable polymeric film can be pretreated, to impart uniformity or improve the adhesion of the coated material.
In a typical process for preparation of a multi-layer laminate according to the present invention, the non uniform embossed metallised film of thickness between 10-150 microns having first and second surfaces is first prepared. The first surface of the substrate is coated with metal sulphide or metal oxide by vacuum evaporation/deposition technique. The non uniform embossed metal sulphide or metal oxide coated film is initially coated with suitable primer for assuring uniform coating and proper adhesion of the metal oxide/sulphide on the polymeric film during vacuum evaporation. The metallized thermoformable film is then subjected to non uniform embossing with a desired art work and design. Optionally coloring of the metallized film can be done to get a coloured

metallized non uniform embossed metallized film. To achieve coloration of the metallized film, the former film is coated with a desired coloured lacquer of thickness 0.5 to 1.5 microns. The application of the colored lacquer can be done before the metallization process or after the metallization process of the polymeric film. Then, the coloured/ without colour metallized polymeric film is subjected to non uniform embossing with a predetermined art work design. The other side of this film is coated with a suitable adhesive of thickness between 0.5-8 microns and laminated with a rigid polymeric base having thickness between 50 to 1000 micron. The adhesive helps to fix the coloured/ without coloured metallized non uniform embossed metallized film to the rigid polymeric base on the second surface of the non uniform embossed metallized polymeric film efficiently. A wide variety of adhesives can be advantageously used according to the present invention. Preferably, the adhesive comprises a polymeric substance capable of undergoing polymerization at higher temperatures. The adhesive coat can be applied by several methods typically known to a person skilled in the art and includes coating and spraying. The wet adhesive coat is then pressed with the desired polymer film. If desired, before applying the colored/ without coloured non uniform embossed metallized film, the adhesive coat is partially dried. Such partial drying at elevated temperature removes volatile components. Once the desired polymer film is applied on the adhesive coat, say by pressing, the laminate may further be subjected to heat treatment. When the adhesive coat comprises a polymerizable substance, the curing of this polymerizable substance occurs through further polymerization, thereby imparting further adhesive strength. However, the post-heat treatment is optional and entirely depends on several parameters such as the nature of the individual constituents and the final properties desired.

A wide variety of polymer films can be used for the thermoformable non uniform embossed metallized film according to the present invention. Typical non-limiting examples of such film include metallized color film such as a metallized polyvinyl chloride (PVC) film or high density polyethylene (HDPE) or low density polyethylene (LDPE) or polypropylene (PP) or amorphous polyethylene terephthalate (APET) and co-polymer of PET with glycol (PETg). The colored film may be obtained commercially or prepared by metallizing a desired polymer film with a suitable metal like aluminum, silver, gold, through known a metallization process, such as for example, vacuum deposition.
Thus the obtained multi-layer laminate having a colored film which is metallized and embossed with a pre determined pattern and having non uniform thickness is laminated with the rigid thermoformable polymeric base .. As mentioned earlier, the thickness of individual layers, including those of the rigid polymeric base, adhesive coat and colored metallized non uniform embossed metallized film can be selected from within a wide range, depending on the specific intended use and/or operational ease.
The multi-layer laminates according to the present invention have excellent bursting strength, barrier properties and deformation resistance. Advantageously, the laminates according to the present invention have high abrasion resistance and also can withstand thermoforming processes without any damage to the non uniform embossed metallized design during the process of thermoforming the film in to blisters packaging. Further, the multilayered thermofromable non uniform embossed metallized film can act against counterfeiting effectively.

From the foregoing description, it will thus be evident that the present invention provides novel multi-layer laminates comprising thermoformable ed non uniform embossed metallized layered polymeric films and at least one rigid polymeric base and a method for their preparation. While certain embodiments of the invention have been described, these embodiments have been presented by way of examples only, and are not intended to limit the scope of the inventions. Variations or modifications to the design and construction of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the invention.
The invention will now be described with reference to the accompanying examples
Example 1
A 35 micron pharmaceutical grade PVC film devoid of plasticizer having 600 mm width was subjected to an unwinder of a gravure coating machine. Ester -acrylic based primer from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using the gravure roller to the PVC film and extra primer was removed by doctoring process. Deposition of this primer had a thickness of 0.8 microns. Then this film was allowed to travel through on-line ovens via a conveyer. The oven temperature was set at a temperature of 75° C and the speed of 30 m/min for drying the primer on the film was maintained. The drying of the primer on the film was confirmed by non tackiness and by non blocking of the rewinding at the re winder roller.

The two layer film formed above was then transferred to a vacuum deposition machine. This machine had an in situ plasma device and was fitted with an evaporation boat in which the material to be deposited was placed. The primer coated surface of the laminated film was first treated with plasma and thereafter was deposited with zinc silphide having 99.99% purity. Thickness of this deposited layer was 0.025 microns. The thickness was achieved by adjusting the speed, height of the gun and the vacuum level.
This three layer film was exposed to a differential embossing grating process. A custom built machine was used for the embossing process. The three layered film was placed on an unwinder of this custom made machine, the film was passed through the roller having temperature of 130 to 150° C by which the film was softened. A diamond pattern shim was pressed on the metallized side of the film to create a diffraction grating embossed effect on the film. The shim made for the above purpose was cut with a diamond pattern by using a computerized laser cutting mechanism to avoid duplication of the pattern by any one else. The other side of this film was then laminated to a 250 micron rigid PVC base by applying an adhesive between 0.5 to 8 microns through the gravure lamination technique.
Blisters packs were formed from this laminate by the thermoforming process which showed excellent thermoforming performance and showed the fine diamond non uniform embossed metallized pattern even after the thermoforming process.
Specification of the film was as follows:
Total thickness 287 micron
Adhesion of embossed pattern with scotch tape test: passes
Thermoforming performance Excellent

Impact strength
Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
- Transverse Heat seal strength WVTR of the blister

955 g
13.5 kg/cm2 13.7Kg/cm2 5.9% 5.8%
0.65 kg/cm 8 g/m2/day

Example 2
A film was produced as per example 1 except thickness of the PVC film was 50 microns and pattern used for embossing was a rain-bow pattern. The three layer film was laminated to. a 250 micron rigid PVC base., |This laminate demonstrated the following properties
Total thickness 304 micron
Adhesion of embossed pattern with scotch tape test: passes

Thermoforming performance
Impact strength
Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
- Transverse Heat seal strength

Excellent >950g 14.05 kg/cm2 14.13 Kg/cm2 6.2 % 6.15% 0.65 kg/cm2

Example 3
A film was produced as per example 1 except thickness of the PVC film was
100 microns and pattern used for embossing was fine grains pattern. The

resulting multilayer film substrate was then laminated to a thermoformable, pharmaceutical grade PVC film of 250 microns devoid of plasticizer, using dry adhesion technology. Solvent based polyurethane adhesive of 4 microns was applied to the latter PVC mono layer film by using gravure coating process. The adhesive suspension that was applied had a viscosity of 24 sec, and was dried at 75° at a machine speed of 30 m/min. The multilayer film demonstrated the following properties.
Total thickness 354 micron
Differentially grated laminated film thickness 100 micron
Adhesive coat 4 microns
Adhesion to substrate & differentially grated laminated film 200 gm/cm
Adhesion of differentially grated laminated with scotch tape test: passes
Thermoforming performance Excellent
Impact strength>950 g
Tensile strength - Longitudinal 20.85 kg/cm
-Transverse 20.6 kg/cm
Elongation - Longitudinal 6.6 %
- Transverse 6.7 %
Example 4
A film was produced as per the example 1 except thickness of the PVC film which was 120 microns and pattern used for embossing was square pattern. The resulting multilayer film substrate was then laminated to a base consisting of three PVC films of thickness 300 microns bounded to each other by using polyurethane based adhesive of thickness 4 microns via gravure coating

technique, using dry adhesion technology as per example 3. The multilayer film demonstrated the following properties
Total thickness 1050 micron
Differentially grated laminated film thickness 120 micron
Adhesive coat 12 microns
Adhesion to substrate & differentially grated laminated film 200 gm/cm
Adhesion of differentially grated laminated with scotch tape test: passes
Thermoforming performance not possible
Impact strength > 900 g
Tensile strength - Longitudinal 50.66 kg/cm
-Transverse 45.44 kg/cm2
Elongation - Longitudinal 8.5 %
- Transverse 7.6 %
Example 5
A film was produced as per the example 2 in which a blue coloured pigmented 50 micron PVC film with text used for embossing with a flower like pattern. The resulting multilayered laminated demonstrated following properties:
Total thickness 304 micron
Differentially grated laminated film thickness 50 micron
Adhesive coat 4 microns
Adhesion to substrate & differentially grated laminated film 200 gm/cm
Adhesion of differentially grated laminated with scotch tape test: passes
Thermoforming performance Excellent
Impact strength > 950 g

Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
- Transverse

14.05 kg/cm2 14.13 kg/cm2 6.2 % 6.15%

Example 6
A film was produced as per example 5 in which a blue coloured pigmented
PVC film of thickness 75 microns and pattern used for embossing was broken
glass pattern. The resulting multilayered laminated demonstrated the following
properties:

Total thickness
blue tinted differentially grated laminated film thickness
Adhesive coat
Adhesion to substrate & differentially grated laminated film

330 micron 75 micron 5 microns
200 gm/cm

Adhesion of differentially grated laminated with scotch tape test: passes

Thermoforming performance
Impact strength
Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
- Transverse

Excellent
>950g 15.5 kg/cm2 15.2 kg/cm2 7.2 % 7.15%

Example 7
A film was produced as per example 1 except that the thickness of the PVC film was 50 microns and the pattern used for embossing was a square pattern. The resulting multilayered film was laminated with a blue coloured tinted 250

micron thick pharmaceutical grade, thermoformable rigid PVC base devoid of plasticizer with the help of gravure coating process using a polyurethane based adhesive of thickness 4 microns . The lamination was effected at 75°C. The resulting film demonstrated the following properties
Total thickness 304 micron
Differentially grated laminated film thickness 50 micron
Adhesive coat 4 microns
Colour Blue
Adhesion to substrate & differentially grated laminated film 200 gm/cm
Adhesion of differentially grated laminated with scotch tape test: passes
Thermoforming performance Excellent
Impact strength > 950 g
Tensile strength -Longitudinal 14.1 kg/cm
-Transverse 14.0 kg/cm2
Elongation - Longitudinal 6.2 %
- Transverse 6.15 %
Example 8
A 35 micron thick thermoformable pharmaceutical grade gold pigmented PVC film with zinc sulphide metallization layer thickness of .033 microns was made to undergo differential grating embossing procedure as per example 1 and further was laminated with a thermoformable pharmaceutical grade PVC film of thickness 300 microns with the help of polyurethane based adhesive coat via gravure coating process. The resultant film demonstrated the following properties

Total thickness 340 micron
Gold tinted differentially grated laminated film thickness 35 micron
Adhesive coat 5 microns
Adhesion to substrate & differentially grated laminated film 200 gm/cm
Adhesion of differentially grated laminated with scotch tape test: passes
Thermoforming performance Excellent
Impact strength > 950 g
Tensile strength - Longitudinal 15.1 kg/cm2
-Transverse 15.0 kg/cm2
Elongation - Longitudinal 6.2%
- Transverse 6.1%
Example 9
A laminate was produced as per example 1 except that the polymeric film was
used from the class of co-polymer of polyethylene terepthalate and glycol
(PETg) film having 50 micron thickness and the pattern used for embossing
was a rain-bow pattern. The resultant laminate demonstrated the following
properties
Total thickness 300 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance Excellent
Impact strength >950 g
Tensile strength -Longitudinal 12kg/cm2
-Transverse 12.1 Kg/cm2
Elongation - Longitudinal 5.5%
- Transverse 5.1%

Example 10
A laminate was produced as per example 1 except that the polymeric film was used from the class of co-polymer of polyethylene terepthalate and glycol (PETg) film having thickness 100 microns and pattern used for embossing was diamond pattern. The resultant laminate demonstrated the following properties
Total thickness 354 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance Excellent
Impact strength 950 g
Tensile strength - Longitudinal 12.5 kg/cm2
-Transverse 12.4 Kg/cm2
Elongation - Longitudinal 5.9 %
- Transverse 5.8 %
Heat seal strength 0.65 kg/cm
Example 11
A laminate was produced as per example 1 except that the polymeric film was used from the class of co-polymer of polyethylene terepthalate and glycol (PETg) film of thickness 12 microns and pattern used for embossing was a square pattern. The laminate demonstrated the following properties
Total thickness 267 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance excellent
Impact strength >950 g
Tensile strength - Longitudinal 6.5 kg/cm

Elongation

-Transverse 5.75 kg/cm2
Longitudinal 5.5 %
Transverse 5.1 %

Example 14
A laminate was produced as per example 1 except that a cast polypropylene film was used as a base having thickness of 300 microns and pattern used for embossing was a diamond pattern. The three layer laminate demonstrated the following properties
Total thickness 335 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance Excellent
Impact strength >350 g
Tensile strength - Longitudinal 2.36 kg/cm2
-Transverse 2.2 Kg/cm2
Elongation - Longitudinal 11.2%
- Transverse 11%
Example 15
A film was produced as per example 1 except that the thickness of the PVC
film was 35 microns and the pattern used was a broken glass pattern. The three
layer film was further laminated with a 300 micron thick cast polypropylene
film by using polyurethane based adhesive of thickness 5 microns with the help
of gravure coating process. The resulting laminate demonstrated the following
properties
Total thickness 340 micron

Adhesion of non uniform embossed pattern with scotch tape test: passes

Excellent >953g 17.39 kg/cm2 16.78 Kg/cm2 6.4% 6.5%
Thermoforming performance
Impact strength
Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
-Transverse Example 16
A laminate was produced as per example 1 except thickness of the PVC film was 100 microns and pattern used was a broken glass pattern. The three layer film was further laminated with a 250 micron thick co-polymer of polyethylene terepthalate and glycol (PETg) film base using a polyurethane based adhesive with the help of gravure coating process. The resulting film demonstrated the following properties
Total thickness 360 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes

Excellent >953g 17.39 kg/cm2 16.78 Kg/cm2 6.4% 6.5%
Thermoforming performance
Impact strength
Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
-Transverse Example 17
A 50 micron pharmaceutical grade PVC film roll devoid of plasticizer having 600 mm width was subjected to un winder of gravure coating machine . A coloured lacquer was then applied to this film having thickness of 4 micron

with the help of gravure technology then after second pass the Ester -acrylic based special primer from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using gravure roller to this PVC film and extra primer was removed by doctoring process. Deposition of this primer had a thickness of 0.8 microns. Then this film was allowed to travel through on line ovens via a conveyer at a temperature of 75° C at the speed of 30 m/min. The drying of the film was ensured by non tacky and non blocking rewinding at the rewinder roller.
Thus the two layer laminate film formed above was then transferred to a vacuum deposition machine. This machine had an in situ plasma device and was fitted with an evaporating boat in which the material to be deposited was placed. The primer coated surface of above laminated film was first treated with plasma and thereafter deposited with a zinc sulphide layer having 99.99% purity, thickness of this deposited layer was 0.020 microns. The thickness was achieved by adjusting the speed, height of gun and vacuum level. Further, this three layer laminated film was exposed to differential embossing grating process. Custom made machine was used for embossing process. The three layered laminated film was then placed on un winder of this custom made machine, the film then was passed through a roller having temperature of 130 to 150° C by which the film was getting soften, then diamond pattern shim was pressed on the metallized side of the laminate to create a diffraction grating on the film. The shim made for the above purpose was cut with a diamond pattern by using computerized laser cutting mechanism to avoid duplication of the pattern by any one else. Then this film was laminated to 200 micron PVC base devoid of plasticizer and having a vinyl chloride monomer concentration of less than 1 ppm and global migration less than 60 ppm.

Blister packs were formed from this film by thermoforming process which
showed excellent thermoforming performance and showed a fine diamond non
uniform embossed metallized pattern even after the thermoforming process.
This laminate exhibited the following properties,
Total thickness 256 microns
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance Excellent
Impact strength 953 g
Tensile strength -Longitudinal 5.11kg/cm2
-Transverse 4.88 Kg/cm2
Elongation - Longitudinal 5%
- Transverse 4.8%
Heat seal strength 0.65 kg/cm
Example 18
A 50 micron pharmaceutical grade PVC film roll devoid of plasticizer having 600 mm width was subjected to the un winder of a gravure coating machine .Ester -acrylic based special primer from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using gravure roller to this PVC film and extra primer was removed by doctoring process. Deposition of this primer had thickness of 0.8 microns. Then this film was allowed to travel through in line ovens via a conveyer at a temperature of 75° C at a speed of 30 m/min. The drying of the film was ensured by non tacky and non blocking rewinding at rewinder roller. Colour lacquer was then applied to this film with the help of the gravure.
Thus the three layer laminate film formed above was then transferred to a vacuum deposition machine. The primer coated surface of above laminated film

was first treated with plasma and zinc sulphide having 99.99% purity, thickness of this deposited layer was 0.1 micron. The thickness was achieved by adjusting the speed, height of gun and vacuum level.
Further, this three layer laminated film was exposed to differential embossing
grating process. Custom made machine was used for the embossing process.
The three layered laminated film was then placed on un winder of this custom
made machine, the film was passed through a roller having temperature of 130
to 150° C by which the film was softened, then a diamond pattern shim was
pressed on the metallized side of the laminate to create a diamond pattern on
the film. Then this film was laminated as per example 17.
Blister packs were formed from this film by a thermoforming process which
showed excellent thermoforming performance and showed the fine diamond
non uniform embossed metallized pattern even after thermoforming process.
The laminate exhibited the following properties,
Total thickness 256 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance Excellent
Impact strength 953 g
Tensile strength - Longitudinal 5.11 kg/cm2
-Transverse 4.88 Kg/cm2
Elongation - Longitudinal 5%
- Transverse 4.8%
Heat seal strength 0.65 kg/cm
Example 19
A 50 micron pharmaceutical grade PVC film roll devoid of plasticizer having
600 mm width was subjected to a un winder of gravure coating machine. Ester

-acrylic based special primer with blue pigment in it from Magma Polymers Private Limited having viscosity of 26 to 32 sec. was applied using gravure roller to this PVC film and extra primer was removed by doctoring process. Deposition of this primer had a thickness of 0.8 microns. This film was allowed to travel through in line ovens via a conveyer at a temperature of 75° C at the speed of 30 m/min. The drying of the film was ensured by non tacky and non blocking rewinding at rewinder roller.
This two layer laminate film formed above was deposited with a zinc sulphide layer of 0.025 microns as per the previous examples. The thickness was achieved by adjusting the speed, height of gun and vacuum level. Further, this three layer film was exposed to a differential embossing grating process. Custom made machine was used for embossing process. The three layered laminated film was then placed on un winder of this custom made machine, the film then was passed through a roller having temperature of 130 to 150° C by which the film was softened, then a diamond pattern shim was pressed on the metallized side of film to create a diamond pattern diffraction grating on the film as per the previous examples. The shim made for the above purpose was cut with a diamond pattern by using computerized laser cutting mechanism to avoid duplication of the pattern by any one else. Then this film was laminated as per example 17 to a base.
blister packs were formed from this film by thermoforming process which
showed excellent thermoforming performance and showed the fine diamond
non uniform embossed metallized pattern even after the thermoforming process,
the laminate exhibited the following properties,
Total thickness 256 micron
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance Excellent

Impact strength 953 g
Tensile strength - Longitudinal 5.11kg/cm2
-Transverse 4.88 Kg/cm2
Elongation - Longitudinal 5%
- Transverse 4.8%
Heat seal strength 0.65 kg/cm

Example 20
Laminate made as per example 1 was coated with a PVDC coating on the other
side of the diffraction grating with help of dispersion coating techniques to
enhance the barrier properties of the laminate .
the laminate exhibited the following properties,
Total thickness 280 micron
Excellent 953 g
5.11 kg/cm2 4.88 Kg/cm2 5% 4.8%
0.65 kg/cm 0.1 gm/cm2/day
Adhesion of non uniform embossed pattern with scotch tape test: passes
Thermoforming performance
Impact strength
Tensile strength - Longitudinal
-Transverse
Elongation - Longitudinal
- Transverse Heat seal strength WVTR

We Claim:
[1] A multilayer thermoformable packaging laminate comprising
(i)a pharmaceutical grade polymeric film substrate, devoid of plasticizer,
and having vinyl monomer content less than 60 ppm, said substrate, having
thickness in the range of 10 to 150 microns,
(ii) a coat of an ester acrylic based primer, having thickness in the range
of 0.1 to 1 micron provided on a first surface of said substrate,
(iii) a metallic compound layer the metallic compound being selected from
a group consisting of a metal sulphide and a metal oxide of non uniform
thickness between 0.001 to 0.3 micron deposited on said coat and embossed
with a predetermined pattern; and
(iv) a polymeric base of thickness between 50 to 1000 micron laminated
on the second surface of said substrate.
[2] A multilayer thermoformable packaging laminate as claimed in claim 1, in which , the polymeric substrate consists of at least one polymeric resin selected from a group of resins consisting of polyvinyl chloride (PVC), Polypropylene (PP), Polyethylene (PE), polyethylene terepthalate (PET) and co-polymers of theses resins.
[3] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the polymeric substrate is transparent, translucent or coloured.
[4] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate is colored and coloring of the polymeric substrate is done by using a colored lacquer or a pigment.

[5] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the base is multilayered and is laminated to the substrate after the pattern is embossed.
[6] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the sulphide of metal is (ZnS).
[7] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the metal oxide is silicon (SiOx and SiOx.nNn).
[8] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the base is multilayered, having a plurality of polymeric layers bonded together, by adhesive bonding, thermal bonding or co-extrusion.
[9] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate is multilayered having at least one transparent layer and at least one colored layer.
[10] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate is multilayered, consisting of polymeric layers adhesive bonded to each other, the adhesive between the layers being pigmented.
[11] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the metal used for sulphide or oxide coating is at least 99% pure metal selected from zinc and silicon.

[12] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the film includes at least one colored or colorless lacquer layer having thickness of 0.5 to 8 microns applied between the substrate and the coat, between the coat and the metal sulphide or metal oxide layer or above the metal sulphide or metal oxide layer.
[13] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the substrate or base includes at least one polymeric layer selected from a group consisting of a moisture barrier layer, an oxygen barrier layer, a gas barrier, and a vapor barrier layer, said layer being provided operably within the substrate, on the substrate and below the coat, or below the substrate, or within the base.
[14] A multilayer thermoformable packaging laminate as claimed in claim 1, in which the embossed pattern is a diamond pattern, a broken glass pattern, a square pattern, a honey comb pattern, a triangular pattern, a wavy line pattern, a star burst pattern; a circular pattern a striation pattern or a combination of patterns and includes text matter.
[15] A process for preparation of a multilayer thermoformable packaging laminate as claimed in claim 1 ,comprising the following steps:
(i) applying a coat of an ester acrylic based primer, upto a thickness in the range of 0.1 to 1 micron upon a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; (ii) partially drying the said primer coat;

(iii) depositing a metal compound selected from sulphide or metal oxide on
the said partially dried primer coat to form a metal sulphide or metal oxide
layer of thickness between .001 to 0.3 microns;and
(iv) embossing the metalized layer with a shim to form an embossed pattern
on the metal compound layer and to make the thickness of the metal
compound layer non uniform;
(v) laminating other side of the substrate with a polymeric base of thickness
50 to 1000 microns.
[16] A process as claimed in claim 15, in which the metal sulphide or metal oxide layer is deposited on the primer coat by vacuum deposition.
[17] A process as claimed in claim 16, which includes a step of applying a lacquer coat, typically a colored lacquer coat either on the film or on the primer coat.

ABSTRACT
A multilayer thermoformable packaging laminate comprising a pharmaceutical grade polymeric film substrate, devoid of plasticizer, and having vinyl monomer content less than 60 ppm, said substrate, having thickness in the range of 10 to 150 microns; a coat of an ester acrylic based primer, having thickness in the range of 0.1 to 1 micron provided on a first surface of said substrate; a metallic compound layer the metallic compound being selected from a group consisting of a metal sulphide and a metal oxide of non uniform thickness between 0.001 to 0.3 micron deposited on said coat and embossed with a predetermined pattern; and a polymeric base of thickness between 50 to 1000 micron laminated on the second surface of said substrate.

Documents:

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Patent Number

270897

Indian Patent Application Number

596/MUM/2008

PG Journal Number

05/2016

Publication Date

29-Jan-2016

Grant Date

27-Jan-2016

Date of Filing

24-Mar-2008

Name of Patentee

BILCARE LIMITED

Applicant Address

1028, SHIROLI, RAJGURUNAGAR, (TALUKA KHED), PUNE

Inventors:

#	Inventor's Name	Inventor's Address
1	BHANDARI MOHAN HARAKCHAND	FLAT NO. 604, MANTRI LAWNS, AUNDH PARK, PUNE 411008.
2	NAIK PRAFUL RAMCHANDRA	C/O.SHRI R.G.NAIK, SANTRUPTI, PRABHAT NAGAR, VADAGERI, HONNAVAR-581334, UTTARA KANADA
3	TILAK AMMANABROLU BALGANGADHAR	CA-6, CLARION PARK, D.P.ROAD, AUNDH, PUNE-411007.
4	BHARADIA RAHUL GOPIKISAN	BB-21, SWAPNASHILP, GANESHNAGAR, KOTHRUD, PUNE-411029.
5	SANJEEV DATTATRAYA KULKARNI	A1/402, VITHOBAKRIPA HOUSING SOCIETY, CHIKAN GHAR, MHASOBA MAIDAN, KALYAN(WEST)-421301.
6	NAIK SUDHIR GAJANANRAO	SUDHANJLI, PLOT NO.144/C SECTOR A, N-1, MIDC ROAD, CIDCO, AURANGABAD-431003.

PCT International Classification Number

B32B27/30; C08K3/32; C08K5/52

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1		1900-01-01	India