Description:[0001] The present disclosure relates to a broad field of cold form laminates with barrier to cross migration in a blister pack. More particularly the present disclosure relates to a moisture repellent polymeric material for packaging solution.

BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the present invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Blister packaging, or blister packs, are pre-formed packaging materials composed of a cold formed and thermoformed plastic cavity and a pliable lid. In this type of packaging, the product is placed in deep-drawn pockets or cavities resembling a blister. A backing material, or lidding mates to the flat area of the plastic cavity enclosing the product inside, and A heat seal bonds the two structures. Blister packaging has various types depending on the application. The most popular use of blister packs is for packaging pharmaceutical products such as pills, tablets, capsules, lozenges and medical packaging for syringes, ampules etc.
[0004] Pharmaceutical products are often packaged in blister packs. A blister pack consists of a flat backing sheet called a lid, usually of cardboard, plastic or metal foil; and a base provided with a formed plastic blister or blister, generally of clear plastic, the backing sheet and blister being joined to form a sealed cavity where the products are. Cold forming packaging materials with effective barrier properties still remains challenge for pharmaceutical packaging. Over the time migration of water vapors from environment into the pack and can adversely influence the product like pharmaceutical formulation, more specifically active pharmaceutical ingredient (API). To reduce the influence of environment and migration of water vapors and oxygen many approaches have been tried. For moisture sensitive products such as solid formulations of pharmaceutical products, laminates with aluminium as barrier layer are used mainly. When such laminates with aluminium layer are used for blister packaging, one of the risks still remains that renders such packaging ineffective is migration of water vapors through the sealed seam of the final pack. In order to improve barrier properties laminates with multiple layers are provided comprising of polymeric layers in addition to the aluminium film.
[0005] Most commonly used blisters are the push-through blisters wherein the cover is made of aluminum foil or an aluminum foil laminate. Aluminum foil is used as the thickness of the material used requires relatively little force to break it. Generally, the base of the blister pack is made of polymeric material such as polyvinyl chloride (PVC), polyamides, polyolefins, polyesters and laminates or multilayer materials containing at least one of these materials and, if desired, aluminum foil.
[0006] Cold-formable laminates made of an aluminium foil covered on both sides with plastics material are used, inter alia, for producing base parts of blister packagings for pharmaceutical products. Wells for receiving individual tablets or other forms of individual doses are formed in the base parts. The aluminium foil is used here primarily as a barrier layer against the passage of water vapour and gases and protects the products primarily from absorbing or giving off moisture.
[0007] Conventional laminates for producing base parts of blister packagings for pharmaceutical products frequently have the structure oPA/aluminium foil/sealing layer. Conventional sealing layers consist of PVC, PP or PE. After filling the wells, an optionally peelable outer foil is sealed against the base parts. Conventional outer foils are optionally aluminium foils which are coated with plastics material, covered with film or lacquered. Blister Packaging Machines for pharmaceutical industry mostly use PVC plastic films as forming materials; however, it is now being replaced due to its negative effects on the environment.
[0008] Accordingly, it would be desirable to provide a barrier offering with sustainable solutions, non-carcinogenic and having lower moisture absorption tendency.

OBJECTS OF THE INVENTION
[0009] It is an object of the present disclosure to provide a multilayer cold form laminate with high barrier to cross migration of water vapor and reduced ingress of oxygen through sealed seam of a blister pack.
[0010] It is a further object of the present disclosure to provide a multilayer cold form laminate comprising double layers of biaxially-oriented polyethylene terephthalate film; an aluminum foils to provide moisture repellent polymeric materials for packaging solution with high barrier to cross migration of water vapor and oxygen through sealed area into cavities when formed into a blister pack.
SUMMARY OF THE INVENTION`
[0011] Accordingly, in a general aspect the present disclosure provides moisture repellent polymeric materials for packaging solution.
[0012] In an aspect the present disclosure provides moisture repellent polymeric materials for packaging solution (multilayer cold form laminate) with high barrier to cross migration of water vapor. The multilayer cold form laminate comprises an intermediate metallized layer laminated with a first substrate on a first side of said metallized layer as an inner layer and a second substrate on a second side of said metallized layer as an outer layer. In an embodiment of the present invention, the metallized layer has a thickness in the range of 200 angstrom to 350 angstrom, the first substrate has a thickness in the range of 15 microns to 50 microns and the second substrate has a thickness in the range of 20 microns to 70 microns.
[0013] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments.

BRIEF DESCRIPTION OF DRAWINGS THE INVENTION
[0001] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles:
FIG.1 illustrates an exemplary diagram of a construction of multilayer cold form laminate with high barrier to cross migration of water vapor in accordance with the present disclosure.
DETAILED DESCRIPTION
[0002] The following is a detailed description of embodiments of the present disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0003] Unless the context requires otherwise, throughout the specification which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense that is as “including, but not limited to.”
[0004] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0005] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0006] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable.
[0007] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein.
[0008] All methods described herein can be performed in suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0009] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
[00010] Various terms are used herein. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0014] The term, “water vapors”, “moisture” and “humidity” as used herein interchangeably refers to the moisture content which can be in the surrounding atmosphere on the outside and inside of the cavity/cavities of a blister pack.
[0015] The terms, “oxygen”, “air”, and “gas” are used interchangeably herein and refers to the air, gas or oxygen in the atmosphere as well as inside the cavity/cavities of a blister pack.
[0016] In one aspect the present disclosure relates to moisture repellent polymeric materials for packaging solution (multilayer cold form laminate) with high barrier to cross migration of water vapor.
[0017] The standard known cold forming laminate used conventionally includes oriented polyamide (oPA) film, aluminum foil and Polyvinyl chloride (PVC) film. The aluminum foil and PVC films are laminated with each other with the help of adhesive. Despite such construction, conventional cold forming laminates do not provide desired effective barrier to cross migration to humidity and oxygen.
[0018] Accordingly, the present disclosure provides a multilayer cold form laminate with high barrier to cross migration of water vapor (Fig. 1). In an aspect the present disclosure provides a multilayer cold form laminate with high barrier to cross migration of water vapor. The multilayer cold form laminate comprises an intermediate metallized layer laminated with a first substrate on a first side of said metallized layer as an inner layer and a second substrate on a second side of said metallized layer as an outer layer. In an embodiment of the present invention, the metallized layer has a thickness in the range of 200 angstrom to 350 angstrom, the first substrate has a thickness in the range of 15 microns to 50 microns and the second substrate has a thickness in the range of 20 microns to 70 microns. The present invention provides a cold form laminate with high barrier to cross migration of water vapor. Such construction is provided to minimize or avoid likelihood of failure during the sealing and cross migration of water vapor through sealed seam and sealed areas. The construction of the cold form laminate in accordance with the present invention is provided to afford high barrier to cross migration of water vapor and oxygen through pin holes present in the aluminium foil and any cracks that may be formed either during the forming or storage.
[0019] In another embodiment of the present invention, the first substrate and the second substrate are a biaxially-oriented film. In an exemplary embodiment of the present invention, the biaxially-oriented film is a biaxially-oriented polyethylene terephthalate film.
[0020] In yet another embodiment of the present invention, the metallized layer is selected from aluminum, copper, aluminum oxide and gold. In an exemplary embodiment of the present invention, the aluminum is selected from grade 8011, 8111, and 8021 and 8079.
[0021] Typically, the first and second substrate and the intermediate metallized layer are integral and monolithic.
[0022] Typically, the first and the second substrate and the intermediate metallized layer are integral and multilayered.
[0023] In an embodiment of the present invention, the multilayer cold form laminate comprises one or more adhesive layer(s) deposited between the first substrate layer and the metallized layer and between the second substrate layer and the metallized layer. The adhesive is selected from polyester base adhesive, polyethylene-based resin, urethane-based adhesives, olefin-based adhesives, butyl rubber-based adhesives, acrylic resin-based adhesives, polyester resin-based adhesives, epoxy resin-based adhesives and silicone resin-based. Typically, the adhesive layer is of the thickness ranging from 1 gsm to 10 gsm.
[0024] In another embodiment of the present invention, the laminate optionally includes at least one colored lacquer layer having thickness of 0.5 to 5 microns applied one of between the first substrate and the metallized layer, between the second substrate and the metallized layer; and above the first substrate.
[0025] In certain embodiments the multilayer cold form laminate comprises a first biaxially-oriented polyethylene terephthalate (BoPET) film, aluminium foil and the second biaxially-oriented polyethylene terephthalate film. Such cold form laminate can comprise of following construction:
- first BoPET film/adhesive/aluminium foil/adhesive/second BoPET film;
- first BoPET film/adhesive/lacquer/aluminium foil/adhesive/second BoPET film; and
- first BoPET film/adhesive/aluminium foil/adhesive/lacquer/second BoPET film.
[0026] The exemplary constructions of the multilayer cold form laminate with specific thickness of individual layers to provide high barrier to cross migration of water vapor and oxygen are shown in Figure 1 and Tables 1-6.
[0027] The cold form laminate in accordance with the present disclosure can be used as a blister base part that may be produced in the known manner.
[0028] The cold form laminate in accordance with the present disclosure can be used on flat forming flat sealing machine, rotary forming and flat sealing, rotary forming and rotary sealing, as well as on flat forming rotary sealing machines.
[0029] In some embodiments the present disclosure provides a blister pack formed from the cold form laminate provided in accordance with the present disclosure as a base part for packing of the product, especially those requiring protection from longer exposure of humidity/moisture and gas/air/oxygen, more particularly requiring cross barrier to water vapor and ingress of oxygen. The blister pack further includes lid layer comprising aluminium and a sealing layer.
[0030] Such blister pack with the cold form laminates provide multifold better cross diffusion barrier to water vapor and also reduce ingress of gases or oxygen, or both as compared to the blister packs with the standard cold form laminates having much thicker constructions. At the same time such a blister construction drastically reduces a fast-gaseous migration of substances out of the blister as needed in some of the products.
[0031] The invention is described in the following by way of examples and with reference to the accompanying drawing.

EXAMPLES
Example 1A
Blister pack with base made from convention cold form laminate
[0032] A standard blister pack was formed from the typical cold form laminate as a base laminate comprising of 40 µm of BoPET film, first layer of adhesive about 5 µm, 50 µm aluminum, second layer of adhesive about 5 µm, and the same was sealed with 50 µm PVC. The total thickness of the blister pack was about 150 µm.

Example 1
Blister pack with base made from the multilayer cold form laminate in accordance with the present disclosure comprising the below mentioned components:
Top layer Adhesive Aluminum Adhesive Sealing layer
Structure 1 40µm BOPET 5 µm 50 µm 5 µm 50µm BOPET
Table 1: Base Laminate
A blister pack was formed from the cold form laminate in accordance with the present disclosure as per Table 1 as a base laminate and the same was sealed with a lidding foil as per components mentioned in Table 2.
Top layer Aluminum Sealing layer
Structure 0.1 g/m² to 5 g/m Primer 7 µm to about 30 µm 1 g/m² to about 15 g/m Heat seal lacquer
Table 2: Lidding foil

Example 2: Forming and sealing study
Machine used for forming and sealing trial: Flat forming, flat, and rotary sealing machine.
Machine speed: 10 cycles/ min to 50 cycles/ min
Sealing temperature: 120 °C to 240 °C
Structure 1 Structure 2
Structure BOPET/adhesive/ Al/ adhesive/ PVC BOPET/adhesive/ Al/ adhesive/ BOPET
Outer BOPET
BOPET MD Tensile (kg/cm2) 1250 to 1350 1250 to 1350
BOPET TD Tensile (kg/cm2) 1450 to 1550 1450 to 1600
BOPET MD Elongation (%) 150 to 225 150 to 225
BOPET TD Elongation (%) 125 to 175 125 to 175
Sealing side BOPET
BOPET MD Tensile (kg/cm2) NA 1250 to 1350
BOPET TD Tensile (kg/cm2) NA 1450 to 1600
BOPET MD Elongation (%) NA 150 to 225
BOPET TD Elongation (%) NA 125 to 175
Number of pinholes in percentage Less than 1% Less than 1%
Water leak test of sealed blisters with lidding foil (450mm hg vacuum for 3 min) Passed Passed
Forming OK/ Not OK Forming is as per the designed change-part and comparable to the conventional structure Forming is as per the designed change-part and comparable to the conventional structure
Table 3: Forming and sealing study

Example 3: Pinhole study with different laminate structures (during blister forming)
Sr. No Structure Observations
1 30 µm BOPET / 4 GSM adhesive / 50 µm Al foil / 4 GSM Adhesive/ 60 µm PVC 20% pinholes observed
2 30 µm BOPET / 4 GSM adhesive / 50 µm Al foil / 4 GSM Adhesive/ 30 µm BOPET 20% pinholes observed
3 36 µm BOPET / 4 GSM adhesive / 50 µm Al foil / 4 GSM Adhesive/ 60 µm PVC Less than 1 % pinholes observed
4 36 µm BOPET / 4 GSM adhesive / 50 µm Al foil / 4 GSM Adhesive/ 36 µm BOPET Less than 1 % pinholes observed
5 MET OD 2.2 / 36 µm PET / 4 GSM adhesive / 50 µm Al foil / 4 GSM Adhesive/ 36 µm BOPET 25% pinholes observed
6 36 µm BOPET / MET OD 2.2 /4 GSM adhesive / 50 µm Al foil / 4 GSM Adhesive/ 36 µm BOPET Less than 1 % pinholes observed
Table 4: Pinhole study with different laminate structures (during blister forming)
Example 4: Delamination study

In stability it is observed that, CFF with BOPET film is having less outer layer delamination tendency as compared with conventional CFF with Nylon film.

0 days 30 days 60 days 90 days 120 days 150 days 180 days
Convention laminate with Nylon (Level of delamination) 0.5 1.2 1.5 1.5 1.5 2 2
CFF with BOPET laminate Level of delamination) 0.5 0.5 0.5 0.5 1 1 1
Table 5: Delamination study
Note:
‘0 level’: No delamination
‘5 level’: Maximum delamination

Example 5: Comparison with conventional material
Sr. No Parameter ASTM Method 25µm BOPA 60µm PVC 36µm BOPET
1 Thickness of film (µm) ASTM D1593 Min.22.5, Avg.25.0, Max.27.5 Min.54.0, Avg.60.0, Max.66.0 Min.32.4, Avg.36.0, Max.39.6
2 Density (g/cm³) ISO 1183 1.15 1.35 1.4
3 Tensile strength (kg/cm²) MD ASTM D882 2000 to 2500 450 to 650 1700 to 2000
4 Tensile strength (kg/cm²) TD ASTM D882 2000 to 2500 450 to 650 1700 to 2000
5 Elongation at break (%) MD ASTM D882 100 to 150 100 to 150 150 to 200
6 Elongation at break (%) TD ASTM D882 100 to 150 100 to 150 125 to 175
Table 6: Comparison with conventional material
[0033] As can be seen from the above Tables 1 to Table 6 it is very clear that the cold form laminate according to the present disclosure was unexpectedly able to provide significantly much higher barrier to the cross migration of the water vapor as compared to the conventional cold form laminate.
[0034] While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The scope of the disclosure is determined by the claims that follow. The disclosure is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art
, Claims:. A multilayer cold form laminate with high barrier to cross migration of water
vapor, said cold form laminate comprising an intermediate metallized layer having
thickness in the range 200 angstrom to 350 angstrom laminated with:
5 - a first substrate having a thickness in the range of 15 microns to 50 microns on
a first side of said metallized layer as an inner layer; and
- a second substrate having a thickness in the range of 20 microns to 70 microns
on second side of said metallized layer as an outer layer.
2. The multilayer cold form laminate as claimed in claim 1, wherein said first
10 substrate and said second substrate is a biaxially-oriented film.
3. The multilayer cold form laminate as claimed in claim 2, wherein said
biaxially-oriented film is a biaxially-oriented polyethylene terephthalate film.
4. The multilayer cold form laminate as claimed in claim 1, wherein said
metallized layer is selected from aluminum, copper, aluminum oxide and gold.
15 5. The multilayer cold form laminate as claimed in claim 4, wherein said
aluminum is selected from grade 8011, 8111, and 8021 and 8079.
6. The multilayer cold form laminate as claimed in claim 1, wherein said first and
second substrate and said intermediate metallized layer are integral and monolithic.
7. The multilayer cold form laminate as claimed in claim 1, wherein said first and
20 second substrate and said intermediate metallized layer are integral and multilayered.
8. The multilayer cold form laminate as claimed in claim 1 wherein said
multilayer cold form laminate comprises one or more adhesive layer(s) deposited
between said first substrate layer and said metallized layer and between said second
substrate layer and said metallized layer.
25 9. The multilayer cold form laminate as claimed in claim 8, wherein said adhesive
in said adhesive layer is selected from polyester base adhesive, polyethylene-based
resin, urethane-based adhesives, olefin-based adhesives, butyl rubber-based adhesives,
acrylic resin-based adhesives, polyester resin-based adhesives, epoxy resin-based adhesives and silicone resin-based.
10. The multilayer cold form laminate as claimed in claim 8, wherein said adhesive layer is of the thickness ranging from 1 gsm to 10 gsm.
11. The multilayer cold form laminate as claimed in claim 1, wherein said laminate includes at least one colored lacquer layer having thickness of 0.5 to 5 microns applied one of between said first substrate and said metallized layer, between said second substrate and said metallized layer; and above said first substrate.