DESC:FIELD
The present disclosure relates to PVC free, high barrier, thermoformable blister laminates.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
The term “Aspect Ratio” of a geometric shape refers to the ratio of its sizes in different dimensions. For example, the aspect ratio of a rectangle is the ratio of its longer side to its shorter side (the ratio of width to length).
The term “Masterbatch” refers to a solid additive for coloring of plastics (color masterbatch) or imparting other properties to plastics (additive masterbatch). Masterbatch is a concentrated mixture of additives encapsulated during a heat process into a carrier resin which is then cooled and cut into a granular shape.
The term “thixotropic” refers to a property of a fluid by virtue of which the apparent viscosity of the fluid is temporarily reduced by previous deformation. This means that with thixotropic material, the viscosity depends on the time of stirring as compared with a pseudoplastic material which depends on the rate of shear.
The term “GSM” refers to “grams per square meter” For this standard, the weight of various types of paper/film is measured from a sample sheet cut to one square meter in size.
The term “blister pack” refers to a formable web/multilayer laminate into which blisters or cavities are formed to pack the product, and a lid or a sealing layer, which is employed as a seal support/ cover the product. The product is placed within the blisters or cavities. It is a pre-formed plastic packaging used for small consumer goods, foods, and for pharmaceuticals.
The term “support” or “base” refers to a layer of a film made up of aluminium foil or a polymer, covering/ protecting the blister pockets or cavities. The term “base” also refers to the plane surface of the laminate sheet from where the stretching takes place to form the cavity or a recess. The recess is thus formed within the laminate, and with a shoulder defining the base material in between the recesses; the recesses of the base are filled with the products; and the base, with the filled recesses, is then covered with a lid, wherein the lid is sealed or otherwise adhered to the shoulder of the base. The lid material provides the base or structural component upon which the final blister package is built. Lid material is made of heat seal lacquer coated paper or a polymer or an aluminium laminate and combination of all these materials that is often called peel off–push through foil.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
For Blisters packaging as well as flexible packaging, thermoformable polymer films or laminates or cold formable aluminum foil based laminates are utilized. Polymers offer good chemical, mechanical and gas/ water vapour barrier to products packaged inside blisters. Polymer packaging materials have distinct advantages over conventional packaging materials like glass bottles, metal containers/ cans or paper boxes. Most of the polymers are processable and recyclable. They are chemically inert so interaction with the product packaged inside does not lead to harmful products. For packaging application purpose, polymeric films or laminates usually are monolayer or multilayered. Polymers that are used for packaging applications are Polyvinyl Chloride, polyolefins, Polyesters, Polystyrene and polyamide as monolayer or multilayer films. Monolayer film alone is unable to offer requisite properties necessary for safety of the packaged product. Therefore, coatings or multilayer laminates are used. Further, solvent based or water based polymeric dispersion are used as coating, lacquers and adhesives. Well known examples of polymers used as water or solvent based dispersions are polyvinylidene dichloride, Polyurethane, polyacrylate and polyesters.
In the present scenario, a disposal of a generated polymer based waste is of great concern. For the disposal of the polymer based waste, methods like incineration, recycling and reuse are generally recommended. Incineration of PVC based waste creates great concern for environment and human beings. Incineration of PVC generates hazardous mutagenic dioxin based compounds under incineration temperature. Dioxin and its various derivatives such as chlorinated Di-Benzodioxins and chlorinated Di-Benzofurans are highly stable and hazardous compounds which pose environmental threat as they are poisonous and mutagenic in nature. As reported, for an oxidation and combustion of the PVC based polymers, the factors such as temperature, humidity, pressure and presence of chlorine, oxygen, carbon and metal salt based stabilizers, play a key role in generation of dioxins and its related compounds. As PVC based polymers has chlorine in the range of 53 mass% to 55 mass%, this chlorine generates hydrogen chloride gas and in turn play key role in the formation of dioxins and related compounds along with carbon monoxide, carbon dioxide, benzene, and toluene under the incineration temperature.
Efforts such as either modification in the monomer itself or copolymerization of two or more monomers resulting in to copolymer, or laminating existing polymeric films with other polymeric films having better barrier properties, for example cyclic olefin copolymer (COC), ACLARTM (poly Chloro-Trifluoro ethylene) laminating with PVC or PET are being carried out to offer better option as polymeric films and laminates with improved barrier properties. Typically, ACLAR is laminated with PVC to form PVC-ACLAR laminates where in PVC usually 250 micrometers thick while thickness of ACLAR varies as per the barrier requirement. ACLARTM films display good thermoformability, better barrier properties than PVC, PET, Polyolefins and other and available in various thicknesses ranging from 21 microns to 102 microns. Thus use of ACLAR film of higher thickness for example 102 micrometer with PVC 250 micrometer will demonstrate highest barrier property than 250 PVC/ 21 ACLAR. However, as ACLAR is expensive, use of ACLAR laminated PVC laminates is economically not viable option.
There is, therefore, felt a need to provide PVC free, high barrier, thermoforming blister laminates that ameliorates the drawbacks mentioned herein above or at least provides a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to ameliorate one or more problems of prior art or to at least provide a useful alternative.
An object of the present disclosure is to provide PVC free, high barrier, thermoformable blister laminates.
Another object of the present disclosure is to provide PVC free, high barrier, thermoforming blister laminates which are economical.
Still another object of the present disclosure is to provide high barrier thermoformable blister laminates at lower PVdC coating thickness.
Yet another object of the present disclosure is to provide high barrier thermoformable blister laminates which can be produced with reduced consumption of materials.
Still another object of the present disclosure is to provide a process for the preparation of the PVC free, high barrier, thermoformable blister laminates.
Yet another object of the present disclosure is to provide a simple process for the preparation of high barrier thermoformable blister laminates.
SUMMARY
The present disclosure relates to PVC free high barrier thermoformable blister laminates. The blister laminates comprise at least one substrate, defining an operative surface. The substrate comprises at least one first polymeric film defining an operative surface, wherein the first polymeric film is devoid of PVC. The substrate also comprises, optionally, at least one second polymeric film, adhered to the operative surface of the first polymeric film by means of an adhesive and at least one third polymeric film on the operative surface of the substrate.
DETAILED DESCRIPTION
The present disclosure relates to PVC free, high barrier, thermoformable blister laminates.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Terms such as “inner,” “outer,” "beneath," "below," "lower," "above," "upper," and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.
For Blisters packaging as well as flexible packaging, thermoformable polymer films or laminates or coldformable aluminum foil based laminates are utilized. Polymers offer good chemical, mechanical and gas/ water vapour barrier to products packaged inside blisters. Polymer packaging materials have distinct advantages over conventional packaging materials like glass bottles, metal containers/ cans or paper boxes. Most of the polymers are processible and recyclable. They are chemically inert so interaction with the product packaged inside does not lead to harmful products. For packaging application purpose, polymeric films or laminates usually are monolayer or multilayered. Polymers that are used for packaging applications are Polyvinyl Chloride, polyolefins, Polyesters, Polystyrene, EVA, EVOH and polyamide as monolayer or multilayer films. Monolayer film alone is unable to offer requisite properties necessary for safety of the packaged product. Therefore, coatings or multilayer laminates are used. Further, solvent based or water based polymeric dispersion are used as coating, lacquers and adhesives. Well known examples of polymers used as water or solvent based dispersions are polyvinylidene dichloride, Polyurethane, polyesters and polyacrylic acid.
In the present scenario, a disposal of a generated polymer based waste is of great concern. For the disposal of the polymer based waste, methods like incineration, recycling and reuse are generally recommended. Incineration of PVC based waste creates great concern for environment and human beings. Incineration of PVC generates hazardous mutagenic dioxin based compounds under incineration temperature. Dioxin and its various derivatives such as chlorinated Di-Benzodioxins and chlorinated Di-Benzofurans are highly stable and hazardous compounds which pose environmental threat as they are poisonous and mutagenic in nature. As reported, an oxidation and combustion of the PVC based polymers, the factors such as temperature, humidity, pressure and presence of chlorine, oxygen, carbon and metal salt based stabilizers play key role in generation of dioxins and its related compounds. As PVC based polymers has chlorine in the range of 53 mass% to 55 mass%, this chlorine generates hydrogen chloride gas and in turn play key role in the formation of dioxins and related compounds along with carbon monoxide, carbon dioxide, benzene, and toluene under the incineration temperature.
Efforts such as either modification in the monomer itself or co-polymerization of two or more monomers resulting in to copolymer, or laminating existing polymeric films with other polymeric films having better barrier properties, for example cyclic olefin copolymer (COC), ACLARTM (poly-Chloro trifluoroethylene) laminating with PVC or PET are being carried out to offer better option as polymeric films and laminates with improved barrier properties. Typically, ACLAR is laminated with PVC to form PVC-ACLAR laminates where in PVC usually 250 micrometers thick while thickness of ACLAR varies as per the barrier requirement. ACLARTM films display good thermoformability, better barrier properties than PVC, PET, Polyolefins and other and available in various thicknesses ranging from 21 microns to 102 microns. Thus, use of ACLAR film of higher thickness for example 102 micrometer with PVC 250 micrometer will demonstrate highest barrier property than 250 PVC/ 21 ACLAR. However, as ACLAR is expensive, use of ACLAR laminated PVC laminates is economically not viable option.
In an aspect, the present disclosure provides PVC free high barrier thermoformable blister laminates.
The blister laminates comprise:
a) at least one substrate, defining an operative surface, wherein the substrate comprising;
i. at least one first polymeric film defining an operative surface, wherein the first polymeric film is devoid of PVC;
ii. optionally, at least one second polymeric film, adhered to the operative surface of the first polymeric film by means of an adhesive;
and
b) at least one third polymeric film, wherein the third polymeric film is disposed on the operative surface of the substrate.
In accordance with an embodiment of the present disclosure, the first polymeric film comprises at least one first polymer.
In accordance with an embodiment of the present disclosure, the first polymer is optionally modified.
In accordance with an embodiment of the present disclosure, the second polymeric film comprises at least one second polymer.
In accordance with an embodiment of the present disclosure, the second polymer is optionally modified.
In accordance with an embodiment of the present disclosure, the third polymeric film comprises at least one third polymer.
In accordance with an embodiment of the present disclosure, the third polymer is optionally modified.
In accordance with an embodiment of the present disclosure, the first polymer is a thermoplastic polymer. In an accordance with an embodiment of the present disclosure, the thermoplastic polymer is optionally modified.
In accordance with an embodiment of the present disclosure, the thermoplastic polymer is at least one selected from the group consisting of polyolefin, polyester, polyamide and polystyrene (PS).
In accordance with an embodiment of the present disclosure, the polyolefin is selected from polyethylene polymer and polypropylene polymer.
In accordance with an embodiment of the present disclosure, the polyethylene polymer is selected from the group consisting of high density polyethylene (HDPE), medium density polyethylene, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), cross-linked polyethylene, chlorinated polyethylene and ultra-high molecular weight polyethylene (UHMWPE).
In accordance with an embodiment of the present disclosure, the polypropylene polymer can be selected from the group consisting of Propylene homopolymer, polypropylene co-polymer, polypropylene random copolymers, polypropylene impact copolymers and polypropylene block copolymers
In accordance with an embodiment of the present disclosure, the polyamide polymer is a blend of semicrystalline polyamide and amorphous copolyamide. The semicrystalline polyamide polymer is selected from the group consisting of Nylon 6, nylon 6,6, Nylon 6,9, Nylon 6,12, Nylon 12,12 and amorphous polyamide copolymer and combinations thereof.
In accordance with an embodiment of the present disclosure, the polyester is selected from the group consisting of amorphous polyethylene terephthalate (APET), polyethylene Terephthalate (PET), glycol modified PET (PETg), Poly (1,3- propylene) terephthalate, Poly (1,4- butylenes) terephthalate, elastomeric polyester comprising poly (1,4-butylene) terephthalate and Poly (tetramethylene ether) glycol blocks.
In accordance with an embodiment of the present disclosure, the polystyrene is selected from the group consisting of atactic polystyrene, syndiotactic polystyrene, isotactic polystyrene, oriented polystyrene, styrene-butadine copolymer and acrylonitrile-butadiene styrene copolymer.
In accordance with an embodiment of the present disclosure, a thickness of the first polymeric film is in the range of 100 µ to 500 µ.
In accordance with an embodiment of the present application, the first polymeric film is a coloured film and the colour is selected from amber, blue, red, peach, orange, white, opaque and green.
In accordance with an embodiment of the present disclosure, the solid content of the material in the first polymer is in the range of 0.5 mass% to 30 mass% with respect to the total mass of the first polymer. The solid content of barrier material in the first polymer refers to the amount of material such as oil dispersion present in the first polymer. The solid content of the material affects the mechanical properties and the barrier properties of the resultant first polymer if the solid content is less than 0.5 mass% and more than 30 mass%. The material acts as a barrier additive for the laminate.
In accordance with an embodiment of the present disclosure, the second polymer is at least one selected from the group consisting of polypropylene (PP), polyethylene (PE), and polyamide (PA). In an exemplary embodiment, the second polymer is polypropylene (PP). In another exemplary embodiment, the second polymer is polyethylene (PE). In yet another exemplary embodiment, the second polymer is a polyamide (PA).
In accordance with an embodiment of the present disclosure, the adhesive is selected from the group consisting of pure acrylic adhesive, ester acrylic adhesive, polyurethane adhesive, polyester based adhesive and polyolefin based adhesive.
In accordance with an embodiment of the present disclosure, a thickness of the second polymeric film is in the range of 10 µ to 60 µ.
In accordance with an embodiment of the present disclosure, the solid content of the material in the second polymer is in the range of 0.5 mass% to 60 mass% with respect to the total mass of the second polymer. The solid content in the second polymer refers to the amount of material such as oil dispersion present in the second polymer. The solid content of the material affects the mechanical properties and the barrier properties of the resultant second modified polymer, if the solid content is less than 0.5 mass% and more than 60 mass%. The material acts as a barrier additive for the laminate.
In accordance with the present disclosure, the adhesive is selected from the group consisting of pure acrylic adhesive, ester acrylic adhesive, polyurethane adhesive, polyester based adhesive and polyolefin based adhesive.
In accordance with an embodiment of the present disclosure, the third polymer is polyvinylidene chloride (PVdC). The polyvinylidene chloride (PVdC) is in an aqueous suspension form.
In accordance with an embodiment of the present disclosure, a thickness of the third polymeric film is in the range of 12µ to 110µ.
In accordance with an embodiment of the present disclosure, an aqueous suspension of the third polymer is made. Typically, this aqueous suspension serves as a coating on the substrate which contributes towards better packaging material. The aqueous suspension of Polyvinylidene chloride (PVdC) (third polymer) serves as a barrier coating material which offers barrier against moisture, and other gases with comparatively better thermoforming ability and mechanical properties.
In accordance with an embodiment of the present disclosure, the solid content of polyvinylidene chloride in the suspension is always in the range of 58% mass to 61 mass % with respect to the total mass of the suspension. In an exemplary embodiment, the solid content of the polyvinylidene chloride in the suspension is 58 mass %with respect to the total mass of the suspension.
When the solid content is in the range of 58% to 61%, the coating of 40 of regular PVdC coated on a nanoparticle modified APET film of a thickness of 225µ provides a water vapour barrier of 0.73 g/m2/d. If the solid content is less than 58%, the coating of 40 gsm will not provide requisite barrier. It will show lower barrier property.
In accordance with an embodiment of the present disclosure, the third polymer is modified with at least one material selected from water absorbing material, water repelling material and a nanomaterial.
In accordance with an embodiment of the present disclosure, a water absorbing material or repelling material is added into the polyvinylidene chloride (PVdC) suspension to achieve better barrier properties at a comparatively lower coating thickness of PVdC material.
In accordance with an embodiment of the present disclosure, the water absorbing material is at least one selected from the group consisting of alumino-silicate clay, dry sodium sulphate, anhydrous calcium chloride, magnesium chloride, sodium chloride, molecular sieves, porous carbon microparticles, cellulose, polyvinyl alcohol, starch, silica, and alumina and biopolymers.
In an exemplary embodiment, the biopolymer is MA Pectin.
In accordance with an embodiment of the present disclosure, the water repelling material is at least one selected from the group consisting of polysiloxane, polyisobutene, polyisoprene, and microcellulose (natural fiber).
In accordance with an embodiment of the present disclosure, a particle size of the microcellulose (natural fiber) is in the range of 40 µ to 50 µ.
In accordance with an embodiment of the present disclosure, the first polymer, the second polymer and the third polymer are independently modified with at least one material selected from a nanomaterial and / or porous carbon microparticles.
In accordance with an embodiment of the present disclosure, the nanomaterial is at least one selected from the group consisting of metal, metal oxide, and clay.
In accordance with an embodiment of the present disclosure, the metal is at least one selected from the group consisting of copper, silver, gold, and zinc.
In accordance with an embodiment of the present disclosure, the metal oxide is at least one selected from the group consisting of alumina, silica, copper oxide, zinc oxide, magnesium oxide, cerium oxide, and iron oxide.
In accordance with an embodiment of the present disclosure, the clay is at least one selected from the group consisting of bentonite, smectite, montomorilonite, and hectrorite.
In accordance with an embodiment of present disclosure, cations such as Na+, K+, Fe+3, Ca+2 when exchanged with quaternary ammonium salts of organic compound form organoclay.
In accordance with the present disclosure, the clay is uniformly exfoliated in the first polymer to obtain a modified first polymer (clay-polymer nanocomposite). Exfoliation is achieved by blending organoclay with the first polymer and by exfoliating through polymerization.
In accordance with the present disclosure, the first polymeric film comprises thermoplastic polymer and nanomaterial masterbatch.
Nanomaterial masterbatch in the present disclosure is prepared by blending nanoparticles in the range of 0.5 mass% to 30 mass% into the first polymer.
In accordance with an embodiment of the present disclosure, the amount of the nanomaterial in the modified polymer is in the range of 0.5 to 30 mass % with respect to the total amount of the composite. In another embodiment, the amount of the nanomaterial in any of the modified polymer is in the range of 0.5 to 25 mass % with respect to the total amount of the composite. In still another embodiment, the amount of the nanomaterial in any of the modified polymer is in the range of 0.5 to 15 mass % with respect to the total amount of the composite. In yet another embodiment, the amount of the nanomaterial in any of the modified polymer is in the range of 0.5 to 10 mass % with respect to the total amount of the modified polymer. In an exemplary embodiment, the amount of the nanomaterial is 13.33 mass%. In another exemplary embodiment, the amount of the nanomaterial is 6.25 mass%. In yet another exemplary embodiment, the amount of the nanomaterial in the modified polymer is 0.8 mass%.
In accordance with the present disclosure, the clay/ metal oxide nanoparticles are blended with the first polymer in the range of 0.5 mass% to 30 mass% to form polymer-organoclay/metal oxide nanocomposite. Masterbatch of organoclay/ metal oxide nanoparticle is blended with masterbatch polymer in the range of 60 mass% to 80 mass% and then pelletized. These masterbatch pellets then are blended into polymer matrix and a film is formed either by calendaring or by extrusion process.
In accordance with an embodiment of the present disclosure, the solid content of the nanomaterial is in the range of 0.1 mass% to 10 mass% in the suspension with respect to the total mass of the suspension. The solid content in the suspension refers to the amount of material such as oil dispersion present in the suspension. Higher weight percentage of the additive affects stability of the polymer suspension therefore, weight percentage of the additive is optimized to obtain better barrier property with stability of the suspension.
In accordance with an embodiment of the present disclosure, the nanomaterial is in the form of nanoparticles, nanoplatelets, nanotubes, and nanofibers.
In accordance with an embodiment of the present disclosure, an aspect ratio of the nanoplatelet is in the range of 5 to 100.
In accordance with an embodiment of the present disclosure, a particle size of the nanomaterial is in the range of 20 nm to 100 nm. In another embodiment, a particle size of the nanomaterial is in the range of 20 nm to 80 nm. In yet another embodiment, a particle size of the nanomaterial is in the range of 20 nm to 40 nm.
In accordance with an embodiment of the present disclosure, the first polymer, the second polymer and the third polymer are modified with porous carbon microparticles.
In accordance with an embodiment of the present disclosure, a particle size of the porous carbon microparticles is in the range of 10 µ to 70 µ. In another embodiment, the particle size of carbon microparticles is in the range of 20 µ to 50 µ. In yet another embodiment, the particle size of carbon microparticles is in the range of 20 µ to 40 µ.
In accordance with an embodiment of the present disclosure, APET having a thickness in the range of 100 to 500 µ is coated with polyvinylidene chloride (PVdC) suspension with variable coating thickness in the range of 5 GSM to 180 GSM. PVdC is associated with various properties such as economical price, enhanced moisture and gas barrier properties.
In accordance with the present disclosure, the modified PVdC based suspension displayed improved barrier properties. This improvement is achieved through introduction of porous carbon microparticles in the PVdC suspension. PVdC suspension can be available in base coat (Solvay A-736) and Top coat (Solvay D-193).
In accordance with the present disclosure, the carbon microparticles are introduced in the base coat and found that these particles are uniformly dispersed in the base coat without change in the pH and the solid content. Coating of these carbon microparticles based suspension applied on thermoformable film/ laminate by air- Knife process or rotogravure process, a uniform coating formed and coated film showed better barrier property at lower coating thickness than conventional PVdC coated thermoformable film/ laminate.
In accordance with an embodiment of the present disclosure, the solid content of the porous carbon microparticles is in the range of 0.1 mass% to 10 mass% in the suspension.
In accordance with the present disclosure, due to crystallinity and polymer chain packing of Polyvinylidene chloride (PVdC), the barrier properties such as low permeability to a wide variety of gases and moisture are obtained. Degree of crystallinity in case of PVdC can reach up to 80%. Further, during the film forming, the polymer chains pack themselves close proximity, thus increasing packing density and leaving less free volume. These two characteristics such as high degree of crystallinity and high packing density of the PVdC provides high barrier properties toward gases and moisture. These characteristics find their roots in symmetric nature of vinylidene chloride unit that would facilitate good packing of polymer chains with very low free volume in amorphous phase.
Conventionally available PVdC suspension contains anti-oxidants, surfactants, and the like with minimum solid content maintained in the range of 58 mass% to 61 mass%. Aqueous PVdC composition is acidic and very sensitive in nature. Incorporation of additional material other than original material to PVdC suspension leads to either breaking of suspension and precipitation, or an increase in pH. The pH of the suspension or dispersion should be maintained below 3. Thus, while mixing of the materials, pH and stability of suspension has to be considered to improve the properties of PVdC.
In accordance with the present disclosure, the porous carbon microparticles are utilized as a filler in the PVdC suspension. The excellent adsorption properties of the porous carbon microparticles find their roots in very high surface area and interactive sites and porosity. These particles are non-hazardous and environmentally friendly. Addition of porous carbon microparticles in the PVdC suspension is carried out in very simple mechanical mixing process. This process does not require any addition of surfactants or stabilizing agents to achieve uniform dispersion. The inventors of the present disclosure have surprisingly found that the use of the porous carbon microparticles do not alter the pH of the PVdC suspension drastically and do not affect stability of the suspension.
In accordance with the present disclosure, the carbon microparticles are added directly to the PVdC suspension under mechanical stirring to obtain a uniform dispersion. Addition of microparticles can also be carried out by preparing aqueous suspension of microparticles and aqueous suspension of microparticles can then be mixed with PVdC suspension under mechanical stirring at room temperature. This microparticle based PVdC suspension is then applied on the polymer substrate to form a uniform transparent coating on polymer substrate which acts as barrier layer to moisture and gases. This suspension is found to be flexible enough so that can easily be used for thermoforming as well as cold forming laminates.
The modified APET films and coated laminates offer an eco-friendly dioxinless alternative to conventional PVC films and coated PVC laminates. In case of APET, there are very less chances of generation of dioxins and related compounds during incineration process due to absence of chlorine in APET. The inventors of the present disclosure have surprisingly found the metal oxide nanoparticles or organoclay or carbon microparticles based APET nanocomposite films and coated laminates as an eco-friendly and safe alternative to PVC based films and laminates with enhanced barrier and mechanical properties.
In accordance with an embodiment of the present disclosure, the PVC free high barrier multilayer blisters laminates comprise:
a. at least one substrate, defining an operative surface, wherein the substrate comprises;
i) at least one polymeric film comprising a polymer devoid of PVC, optionally modified with at least one nanomaterial, defining an operative surface;
ii) optionally at least one polyethylene film comprising a polyethylene polymer optionally modified with at least one nanomaterial, adhered to the operative surface of the first polymeric film by means of an adhesive; and
b. at least one PVdC film comprising a PVdC polymer optionally modified with at least one nanomaterial, disposed on the operative surface of the substrate.

In accordance with an embodiment of the present disclosure, the high barrier multilayer laminate for thermoforming blisters comprises:
a. at least one polymeric film comprising a polymer devoid of PVC, defining an operative surface and
b. at least one PVdC film comprising PVdC optionally modified with at least one nanomaterial, disposed on the operative surface of the polymeric film devoid of PVC.
In accordance with an embodiment of the present disclosure, the high barrier multilayer laminate for thermoforming blisters comprises:
a. at least one polymeric film comprising a polymer devoid of PVC defining an operative surface; and
b. at least one PVdC film comprising PVdC modified with cellulose (natural fiber), disposed on the operative surface of the polymeric film devoid of PVC.
In accordance with an embodiment of the present disclosure, the high barrier multilayer laminate for thermoforming blisters comprises
a. at least one polymeric film comprising a polyolefin devoid of PVC optionally modified with at least one nanomaterial, defining an operative surface; and
b. at least one PVdC film disposed on the operative surface of the polyolefinic film devoid of PVC.
In accordance with an embodiment of the present disclosure, the high barrier multilayer laminate for thermoforming blisters comprises:
a. at least one substrate, defining an operative surface, the substrate comprising;
i. at least one polymeric film comprising a polymer devoid of PVC, defining an operative surface; and
ii. at least one polypropylene (PP) film, adhered to the operative surface of the polymeric film devoid of PVC, by means of an adhesive;
and
b. at least one PVdC film comprising PVdC optionally modified with at least one nanomaterial, disposed on the operative surface of the substrate.
In accordance with an embodiment of the present disclosure, the high barrier multilayer laminate for thermoforming blisters comprises:
a. at least one substrate, defining an operative surface, the substrate comprising;
i. at least one polymeric film comprising a polymer devoid of PVC, defining an operative surface;
ii. at least one polypropylene (PP) film comprising polypropylene (PP) modified with at least one nanomaterial, adhered to the operative surface of the polymeric film devoid of PVC, by means of an adhesive;
and
b. at least one PVdC film disposed on the operative surface of the substrate.
In accordance with an embodiment of the present disclosure, the high barrier multilayer laminate for thermoforming blisters comprises:
a. at least one substrate, defining an operative surface, the substrate comprising;
i. at least one polymeric film comprising a polymer devoid of PVC, defining an operative surface;
ii. at least one polypropylene (PP) film comprising polypropylene (PP) modified with at least one nanomaterial, adhered to the operative surface of the polymeric film devoid of PVC film, by means of an adhesive;
and
b. at least one PVdC film comprising PVdC optionally modified with porous carbon microparticles, disposed on the operative surface of the substrate.
In accordance with an embodiment of the present disclosure, the PVC free high barrier multilayer blisters laminates comprise:
a. at least one APET film, defining an operative surface; and
b. at least one PVdC suspension modified with at least one nanomaterial disposed on the operative surface of the APET film.
In accordance with an embodiment of the present disclosure, the PVC free high barrier multilayer blisters laminates comprise:
a. at least one substrate, defining an operative surface comprises;
iii. at least one polymeric film comprising APET modified with at least one nanomaterial, defining an operative surface; and
iv. at least one PP film, adhered to the operative surface of the polymeric film by means of an adhesive;
and
b. at least one PVdC suspension modified with at least one nanomaterial disposed on the operative surface of the substrate.
In accordance with an embodiment of the present disclosure, the PVC free high barrier multilayer blisters laminates comprise:
a. at least one substrate, defining an operative surface comprises;
i. at least one polymeric film comprising APET modified with at least one nanomaterial, defining an operative surface; and
ii. at least one PP film adhered to the operative surface of APET modified with at least one nanomaterial film by means of an adhesive;
and
b. at least one PVdC suspension modified with porous carbon microparticles disposed on the operative surface of the substrate.
PVdC suspension modified with nanomaterial and coated on PVC laminates; regular PVC and PVC coated with regular PVdC films are studied as per method for determining Water vapour transmission rate (WVTR) given under USP 671. Typically, the films are formed in to blisters and then filled with pre- dried coloured silica beads. The silica filled blisters are then sealed with aluminium foil based lidding foil and exposed to 40°C and 75% RH in a Humidity chamber or stability study chamber. A study of weight gain for the exposed blister is carried out for at least 35 days.
In another aspect, the present disclosure relates to a process for the preparation of a high barrier thermoforming blister laminate. In the process, a predetermined amount of a first polymer is obtained. Optionally, the first polymer is modified by using a predetermined amount of a material to obtain a modified first polymer. Thereafter, a film of the first polymer is made to obtain a first polymeric film.
In the next step, a second polymeric film, is obtained and adhered to the first polymeric film using at least one adhesive to obtain a substrate. Thereafter, a predetermined amount of a third polymer suspension is obtained. The third polymer is optionally modified by adding a predetermined amount of a material to the third polymer to obtain a modified suspension. Thereafter, the suspension is coated on the substrate to form a coating of a predetermined thickness, followed by drying the coating at a predetermined temperature to obtain a high barrier thermoforming blister laminate.
In accordance with an embodiment of the present disclosure, the blister laminates are characterized by having a weight gain per day of less than 0.04 g/day as per USP 671 method.
The foregoing description of the embodiments has been provided for purposes of illustration and is not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial scale.
EXPERIMENTAL DETAILS
Example 1: Nanomaterial modified APET (having a thickness of 225 µ) nanocomposite and carbon microparticle modified APET films, in accordance with the present disclosure
Virgin amorphous polyethylene terephthalate (APET) resin pellets were taken into silos/hoppers. 30 mass% of aluminium oxide nanoparticles having a size of 20 nm were obtained. The Virgin APET film resin pellets passed through the silos/hoppers to obtain an APET mixture and the aluminium oxide nanoparticles were added into the APET mixture to obtain an APET- aluminium oxide nanoparticles mixture. The APET- aluminium oxide nanoparticles mixture was charged into the extrusion screws to obtain nanoparticles modified APET molten mass. The temperature in the extrusion screws was maintained at 270 °C. The nanoparticles modified APET molten mass was pumped into T die to obtain nanoparticles modified APET film having a thickness of 225 µ. The temperature of the T die was also maintained at 270 °C. The nanoparticles modified APET film was used for blister preparation.
Carbon microparticles (0.7 mass %) modified APET (225 microns) was prepared with the same method as explained above by extrusion method.
Blisters (5 each) were formed at 130 °C by using a flatbed thermoforming machine. Barrier performance was studied according to USP 671 procedure. Also, normal APET blisters having a thickness of 250 µ were formed by conventional method. The formed blisters were then packed with previously dried colored silica desiccant beads and sealed at 170°C with aluminium lidding foil having water base HSL (heat sealing layer). Silica beads packed blisters were then exposed to 40°C and 75% relative humidity in a stability chamber and a weight gain were recorded. After 35 days, a rate of weight gain was recorded.
The weight gain of the resulting nanomaterial modified APET film is mentioned in Table 1:
Table 1: The weight gains of the normal APET and modified APET nanocomposite films at 35th day
Composite/film Values (weight gain in g/day) at 35th day
normal 250 µ of APET Blister 0.0222
225 µ of APET modified with nanomaterial blister 0.0226
225µ of APET modified with carbon microparticles blister 0.0186
From Table 1, it is evident that the weight gain per day of the blister formed by modified APET is lesser as compared to the normal APET film. Moreover, the WVTR of the normal 250 µ of APET Blister was found to be 4.96 g/m2/day, the WVTR of 225 µ of modified APET nanocomposite blister was found to be 4.66 g/m2/day and the WVTR of 225µ of modified APET with carbon microparticles was found to be 3.68 g/m2/day. Thus, it can be concluded that modification of the APET film leads to a lesser weight gain and in turn a lower WVTR values thereby providing improved barrier properties.
Example 2: PVdC coating on Nanomaterial modified APET (having a thickness of 225 µ) films, in accordance with the present disclosure
The same experimental procedure was repeated as per the example 1 for nanoparticle modification and preparation of the nanoparticles modified APET film. The nanomaterial modified APET film was used for blister preparation. Commercially available aqueous PVdC suspension from Solvay (A 736) was obtained. The PVdC suspension was coated on the nanomaterial modified APET films to obtain different thicknesses of 40 GSM and 60 GSM. The same procedure was followed as mentioned in example 1 for weight gain studies.
The weight gain of the resulting nanomaterial modified APET film material is mentioned and compared with 250µ PVC coated with 60 GSM regular PVdC in Table 2:
Table 2: The rate of weight gain of the resulting composite of 40 GSM and 60 GSM of PVdC coating on APET nanocomposite film of thickness 225 µ and 250µ PVC coated with 60 GSM regular PVdC after 35 days
Composite/film Values (weight gain in g/day) at 35th day
60 GSM regular PVdC coated on 250µ PVC 0.0122
40 GSM of regular PVdC coated on nanoparticle modified APET film of a thickness 225 µ 0.0117
60 GSM of regular PVdC coated on nanoparticle modified APET film of a thickness 225 µ 0.0089
From Table 2, it is evident that the weight gain of the blister formed by 60 GSM of regular PVdC coated on nanoparticle modified APET film of a thickness 225 µ is lesser as compared to 250 µ PVC coated with 60 GSM regular PVdC and 40 GSM regular of PVdC coated on nanoparticle modified APET film of a thickness 225 µ.
Moreover, the WVTR of the 40 GSM of regular PVdC coated on nanoparticle modified APET film of a thickness 225 µ was found to be 0.73 g/m2/day, and the WVTR of 60 GSM of regular PVdC coated on nanoparticle modified APET film of a thickness 225 µ was found to be 0.65 g/m2/day. Thus, it can be concluded that the increases in the thickness and due to modification of the APET film leads to a lesser weight gain and in turn a lower WVTR values thereby providing improved barrier properties.
Example 3: 1.5% organoclay modified PVdC having a thickness of 25 GSM coated on APET film (having a thickness of 250 µ), in accordance with the present disclosure
1.5 mass% of organoclay powder was dispersed uniformly in PVdC suspension (A- 736, Solvay, 58% solid) under mechanical stirring at 1400 rpm. Mixing of organoclay powder was carried out for 30 minutes. After uniform mixing, a uniform suspension was obtained without any appreciable change in pH, specific gravity and total solid content of the PVdC suspension. The organoclay based suspension was then coated on 250 µ of APET by using conventional commercial coating machine. Coating thickness thus achieved during coating found to be 25 GSM. The organoclay based PVdC coated APET films were then subjected to barrier testing under standard USP 671 protocol, wherein 5 blisters were formed on a flatbed thermoforming machine at 130°C, filled with pre dried silica beads and sealed with aluminium based lidding foil. These silica bead packed blisters were then exposed to 40°C and 75% RH in a humidity chamber. Samples were taken out periodically and kept to attain room temperature and weight gain for blisters was recorded. Weight gain exercise was carried out till 35 days as per the USP 671 protocol.
Table 3: The weight gains of the resulting organoclay modified 25 GSM of PVdC coated on APET film of 250 µ film
Composite/film Values (weight gain g/day) at 35th day
40 GSM of PVdC coated on 250 µ of APET 0.0133
1.5% organoclay modified 25 GSM of PVdC coated on 250 µ of APET 0.0125
From Table 3, it is evident that the weight gain of the blister formed by 1.5% organoclay modified 25 GSM of PVdC coated on 250 µ of APET is lesser as compared to 40 GSM of PVdC coated on 250 µ of APET.
Moreover, the WVTR of 40 GSM of PVdC coated on 250 µ of APET was found to be 0.8138 g/m2/day, and the 1.5% organoclay modified 25 GSM of PVdC coated on 250 µ of APET was found to be 0.7148 g/m2/day. Thus, it can be concluded that due to modification of the APET film leads to a lesser weight gain and in turn a lower WVTR values thereby providing improved barrier properties, even after reducing the thickness.
Example 4: 60 GSM of PVdC modified with 2.5 mass% of organoclay coated on polypropylene (PP) (having a thickness of 25 µ) and APET film (having a thickness of 225 µ) modified with aluminium oxide nanoparticles, in accordance with the present disclosure
2.5 mass% of organoclay was suspended in PVdC base coat (A- 736 Solvay, 58% solid) under mechanical stirring for 30 minutes. After uniform mixing, a uniform suspension was obtained without any appreciable change in pH, specific gravity and total solid content of the PVdC suspension. The organoclay based suspension was then coated on 25 µ of polypropylene (PP) and 225µ nanomaterial modified APET film by using conventional commercial coating machine to obtain a PVdC modified with organoclay coated on polypropylene (PP)- APET film. Coating thickness thus achieved during coating was found to be 60 GSM. This laminate is used for preparation of 5 blister packs. The same experimental procedure was followed for weight gain study as mentioned in example 1.
Table 4: The weight gains of the resulting 60 GSM of PVdC modified with 2.5 mass% of organoclay coated on polypropylene (PP) (having a thickness of 25 µ) and nanoparticle modified APET film (having a thickness of 225 µ) modified with aluminium oxide nanoparticles
Composite/film Values (weight gain g/day) at 35th
90 GSM of PVdC coated on 250 µ of PVC 0.0086
60 GSM of PVdC modified with 2.5 mass% of organoclay coated on polypropylene (PP) (having a thickness of 25 µ) and nanoparticle modified APET film (having a thickness of 225 µ) modified with aluminium oxide nanoparticles 0.0077
From Table 4, it is evident that the weight gain of the blister formed by 60 GSM of PVdC modified with 2.5 mass% of organoclay coated on polypropylene (PP) (having a thickness of 25 µ) and APET film (having a thickness of 225 µ) modified with aluminium oxide nanoparticles is lesser as compared to 90 GSM of PVdC coated on 250 µ of PVC.
Example- 5: 40 GSM and 60 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide nanoparticles, in accordance with the present disclosure
0.4 mass % of porous carbon microparticles were dispersed thoroughly in 2 liters of water to obtain a slurry and then this so obtained slurry was mixed with PVdC suspension with vigorous mechanical stirring. Uniform suspension of porous carbon microparticles in PVdC was obtained. The same experimental procedure was repeated as per the example 1 for nanoparticle modification and preparation of the nanoparticles modified APET film.
Modified APET film then laminated with 25µ PP film to obtain 225µmodified APET/ PP laminate. 60 GSM of carbon microparticle modified PVdC suspension then coated on APET/PP laminate. This laminate is used for preparation of 5 blister packs. The same experimental procedure was followed for weight gain study as mentioned in example 1.
Table 5: The weight gains of the resulting 40 GSM and 60 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide nanoparticles
Composite/film Values (weight gain g) at 35th day
90 GSM of PVdC coated on 250 µ of PVC 0.0086
40 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide 0.0094
60 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide 0.0085
From Table 5, it is evident that the weight gain of the blister formed by 60 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide is comparable to 90 GSM of PVdC coated on 250 µ of PVC.
Moreover, the WVTR of 40 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide was found to be 0.58 g/m2/day, and the WVTR of 60 GSM of PVdC modified with porous carbon microparticles coated on polypropylene (PP) (having a thickness of 25 µ) modified with aluminium oxide nanoparticles and APET film (having a thickness of 225 µ) modified with aluminium oxide was found to be 0.4038 g/m2/day. Thus, it can be concluded that the increases in the thickness and due to modification of the APET film leads to a lesser weight gain and in turn a lower WVTR values thereby providing improved barrier properties.
Example 6: carbon microparticle modified PVdC coated on carbon microparticle modified APET/ PP laminate
Carbon microparticle modified APET film (225 microns) was prepared as explained in example 1. Modified APET film then laminated with 25 microns PP film using ester acrylic based adhesive on lamination machine. In a vessel aqueous carbon microparticle suspension of precalculated mass % (0.4%) was mixed with polyvinylidene dichloride (PVdC) suspension under mechanical stirring. Carbon microparticle modified PVdC suspension applied of thickness 60 gsm on the modified APET/ PP laminate.
The modified APET/ PP/PVdC laminate from this example and, these samples were used for blister preparation. Blisters (5 each) were formed at 130 °C by using a flatbed thermoforming machine. Barrier performance was studied according to USP 671 procedure. Also, normal 90 gsm PVdC coated PVC 250 micron GC film was used for preparation of blisters for comparison of weight gain studies. The formed blisters were then packed with previously dried colored silica desiccant beads and sealed at 170°C with aluminium lidding foil having water base HSL (heat sealing lacquer). Silica beads packed blisters were then exposed to 40°C and 75% relative humidity in a stability chamber and a weight gain were recorded. After 35 days, a rate of weight gain was recorded.
Table 6: weight gain comparison for 1) 250 PVC/ 90 gsm PVdC, and 2) carbon microparticle modified APET 225 microns/ 25 microns PP/ 60 gsm carbon microparticles modified PVdC
Sr.No. Composite Weight gain (g) at 35th day
1 250 microns PVC/ 90 gsm PVdC 0.0086
2 225 microns modified APET/ 25 microns PP/ 60 gsm modified PVdC 0.0091
After comparing weight gain per day, it was found that laminate having modified 225 microns APET and modified PVdC showed comparable weight gain with 250 micron PVC/ 90 GSM PVdC.

TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of the PVC free, high barrier, thermoforming blister laminates:
• that achieved barrier property at lower PVdC coating thickness;
• that have high barrier against moisture, gases and light.
and
a process for the preparation of the PVC free, high barrier, thermoforming blister laminates is:
• simple and environment friendly.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step,” or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation 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 numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:WE CLAIM:
1. A PVC free high barrier thermoformable blister laminates comprising:
a) at least one substrate, defining an operative surface, wherein said substrate comprising;
i. at least one first polymeric film defining an operative surface, wherein said first polymeric film is devoid of PVC;
ii. optionally, at least one second polymeric film, adhered to the operative surface of said first polymeric film by means of an adhesive;
and
b) at least one third polymeric film wherein said third polymeric film is disposed on said operative surface of said substrate.

2. The blister laminates as claimed in claim 1, wherein
a. said first polymeric film comprises at least one first polymer, wherein said first polymer is optionally modified;
b. said second polymeric film comprises at least one second polymer, wherein said second polymer is optionally modified; and
c. said third polymeric film comprises at least one third polymer, wherein said third polymer is optionally modified.

3. The blister laminates as claimed in claim 2, wherein said first polymer is a thermoplastic polymer.

4. The blister laminates as claimed in claim 3, wherein said thermoplastic polymer is selected from the group consisting of polyolefin, polyester, polyamide and polystyrene (PS).

5. The blister laminates as claimed in claim 4, wherein
• said polyolefin is a polyethylene polymer and a polypropylene polymer, wherein said polyethylene polymer is selected from the group consisting of high density polyethylene (HDPE), medium density polyethylene, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), cross-linked polyethylene, chlorinated polyethylene and ultra-high molecular weight polyethylene (UHMWPE); and said polypropylene polymer is selected from propylene homopolymer, polypropylene co-polymer, polypropylene random copolymers, polypropylene impact copolymers and polypropylene block copolymers;
• said polyamide polymer is a blend of a semicrystalline polyamide and an amorphous copolyamide wherein said semicrystalline polyamide polymer is selected from the group consisting of Nylon 6, Nylon 6,6, Nylon 6,9, Nylon 6,12, Nylon 12,12 and copolymers thereof;
• said polyester is selected from the group consisting of amorphous polyethylene terephthalate (APET), polyethylene terephthalate (PET), glycol modified polyethylene terephthalate (PETg), poly (1,3- propylene) terephthalate, poly (1,4- butylenes) terephthalate, poly (tetramethylene ether) glycol block; and
• said polystyrene is selected from the group consisting of atactic polystyrene, syndiotactic polystyrene, isotactic polystyrene, oriented polystyrene, styrene-butadiene copolymer and acrylonitrile-butadiene styrene copolymer.

6. The blister laminates as claimed in claim 1, wherein a thickness of said first polymeric film is in the range of 100µ to 500µ.
7. The blister laminates as claimed in claim 6, wherein a thickness of said first polymeric film is in the range of 200 µ to 350 µ.

8. The blister laminates as claimed in claim 1, wherein said first polymeric film is a colored film.

9. The blister laminates as claimed in claim 2, wherein said second polymer is at least one selected from the group consisting of polypropylene (PP), polyethylene (PE), and polyamide (PA).

10. The blister laminates as claimed in claim 1, wherein said adhesive is selected from the group consisting of pure acrylic adhesive, ester acrylic adhesive, polyurethane adhesive, polyester based adhesive and polyolefin based adhesive.

11. The blister laminates as claimed in claim 1, wherein a thickness of said second polymeric film is in the range of 10 µ to 60 µ.

12. The blister laminates as claimed in claim 2, wherein said third polymer is polyvinylidene chloride (PVdC).

13. The blister laminates as claimed in claim 1, wherein a thickness of said third polymeric film is in the range of 12µ (20 gsm) to 110µ (180gsm).

14. The blister laminates as claimed in claim 1, wherein

• said first polymer is modified with at least one material selected from a nanomaterial and porous carbon microparticles, wherein an amount of said material is in range of 0.5 mass% to 30 mass % with respect to the total amount of said first polymer;
• said second polymer is modified with at least one material selected from a nanomaterial and porous carbon microparticles, wherein an amount of said material is in range of 0.5 mass% to 60 mass % with respect to the total amount of said second polymer; and
• said third polymer is modified with at least one material selected from a nanomaterial, a water absorbing material and a water repelling material, wherein an amount of said material is in range of 0.1 mass% to 10 mass % with respect to the total amount of said third polymer.

15. The blister laminates as claimed in claim 14, wherein said nanomaterial is at least one selected from the group consisting of metal, metal oxide, and clay.

16. The blister laminates as claimed in claim 15, wherein said metal is at least one selected from the group consisting of copper, silver, gold, and zinc.

17. The blister laminates as claimed in claim 15, wherein said metal oxide is at least one selected from the group consisting of alumina, silica, copper oxide, magnesium oxide, zinc oxide, cerium oxide, and iron oxide.

18. The blister laminates as claimed in claim 15, wherein said clay is at least one selected from the group consisting of bentonite, smectite, montomorilonite, hectrorite and organoclay.

19. The blister laminates as claimed in claim 14, wherein

• said water absorbing material is at least one selected from the group consisting of alumino-silicate clay, dry sodium sulphate, anhydrous calcium chloride, magnesium chloride, sodium chloride, molecular sieves, porous cabon microparticles, cellulose, polyvinyl alcohol, starch, silica, and alumina and biopolymers; and
• said water repelling material is at least one selected from the group consisting of polysiloxane, polyisobutene, polyisoprene, and microcellulose.

20. The blister laminates as claimed in claim 14, wherein a particle size of said nanomaterials is in the range of 20 nm to 100 nm.
21. The blister laminates as claimed in claim 14, wherein a particle size of said porous carbon microparticles is in the range of 10 µ to 70 µ.

22. The blister laminates as claimed in claim 1 characterized by having a weight gain of less than 0.04 g/day as per USP 671 method.
Dated this day of April, 2023

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K.DEWAN & CO.
Authorized Agent of Applicant

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI