DESC:FIELD OF THE INVENTION
[0001] The present disclosure relates to a broad field of cold form laminates with barrier property against moisture, air, or both for a blister pack. More particularly, the present disclosure relates to a cold form laminate with sealing layer providing barrier to moisture, air, or cross migration of both and blister pack formed therefrom.

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 presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] For the packaging of moisture sensitive products for example solid formulations of pharmaceutical products laminates with aluminum as barrier layer are used mainly. Such laminates are formed into packages like pouch, sachet, strip pack, or converted into cold form foil (CFF). The products packed into such packaging are protected until the shelf live is over, which may be normally 3 to 5 years in case of pharmaceutical products.
[0004] However, one of the risks still remains that renders such packaging ineffective, which is related to the migration of gases through the sealed seam (Figure 1) of the final pack. After separating of the blisters in the blister machine, the land area is not protected by aluminum. Over the time the gases from environment will migrate into the pack and can influence the product like pharmaceutical formulation, more specifically active pharmaceutical ingredient (API). Such migration of gases into the pack is usually dependent on humidity, temperature, affinity of the product to humidity and/or oxygen, width of sealed seam, thickness of sealing layer, sealing geometry and ratio of volume of the cavity and size of the product. To this end many approaches have been tried to reduce the influence of environment for example, vacuuming of the pack; floating with dry inert gas like modified atmosphere packing (MAP) or air in cases where the oxygen is not the critical factor for the product stability; placing packs such as blister, strip, or pouch into a pouch, or container for example bottle with or without desiccant; use desiccant in the pack like pouch or desiccant integrated in the sealing layer.
[0005] To overcome such challenges, cold form foils are used in blister packaging of pharmaceutical dosage forms. A pharmaceutical packaging blister pack produced by cold forming is usually made of base laminate comprising of 25 µm of oriented polyamide (oPA) film, adhesive, 45 to 80 µm aluminum; and sealing layer made up of 60 or 100 µm PVC, adhesive and heat seal lacquer layer; and a lidding foil made of 15 / 20 / 25 or 30 µm thick hard or soft temper aluminum and heat seal lacquer which is generally 7.0 g/m2 with sealing area of 5.6 µm, for push through and peel/peel-push blister pack. Any reduction in thickness of heat seal lacquer could affect the seal integrity. This necessitates approach which could reduce migration of humidity and/or oxygen and still does not impact seal integrity.
[0006] As newer active pharmaceutical ingredients (APIs) are introduced, such new APIs as well as existing APIs and formulations need improved barrier to oxygen and humidity. To reduce such migration in blister packs, some of the solutions include separate cavity with desiccant (“fish-bone blister”), packaging of blister pack in pouch with desiccant, or sealing layer of the blister pack can be integrated with chemical desiccant such as calcium oxide. All such solutions require more material, additional machines for example for additional packaging in pouch or highly costly laminate such as those with integrated desiccant with complicated logistic in addition. Further, these solutions also do not adequately reduce the migration and thus impacting the shelf life of the drugs, or formulations packed therein.
[0007] To some extent in blister packs for increasing the shelf life, sealing layer is used which has better barrier properties. Cold form laminate with integrated desiccant material in the sealing layer for example EAA-LDPE/CaO-HDPE is available in the market. With this material humidity in the cavity is kept at 10% r.H. over a long time (approximately 17 years at normal and 2.25 years under accelerated conditions). Usually shelf life of pharmaceutical products is 2 to 3 years, in some cases 5 years, hence use of material with barrier to moisture, maintaining low humidity for as long as 17 years seems unnecessary. The product thus seems to be clearly overpacked with costly sealing layer having desiccant material integrated therein. Further, due to reduced humidity to such an extent, hard gelatin capsules become brittle and there is a possibility that they will break when pushed out of cavity. Cold form laminate with integrated desiccant material is not suitable for packaging of moisture sensitive dry powder for inhalation as well. Because of the extreme dry condition, the static of the power becomes high and too much of the product will stay in the cavity after inhalation, thus leading to patient getting insufficient dose, thus adversely affecting the treatment.
[0008] Beside this, logistic of cold form laminate with integrated chemical desiccant is complicated. If reel of the cold form laminate is at machine and taken out of the pouch with vacuum, it has to be used up or will be wasted adding to the cost.
[0009] Thus, there exists an unmet demand to provide materials for packaging and manner of packaging to provide barrier and reduce the migration of gas/air and humidity into blister packs, especially those used for packing pharmaceutical formulations, particularly for humidity and/or oxygen sensitive active pharmaceutical ingredients by cross diffusion.
[0010] The present invention satisfies the existing needs, as well as others, and generally overcomes the deficiencies found in the prior art.

OBJECTS OF THE INVENTION
[0011] It is an object of the present disclosure to provide a cold form laminate including one or more sealing layer(s) for providing barrier to humidity, oxygen, or both.
[0012] It is a further object of the present disclosure to provide a blister pack formed from a cold form laminate comprising one or more sealing layer(s) to provide barrier to humidity, oxygen, or cross migration of both.

SUMMARY OF THE INVENTION
[0013] Aspects of the present disclosure relate to a cold form laminate to be formed into base parts of blister packs for products which are sensitive to moisture, oxygen or both.
[0014] In one aspect, presented herein is a cold form laminate comprising one or more sealing layer(s) for providing barrier to moisture, oxygen, or both. In a particular aspect, the cold form laminate has the structure: polymer layer/oriented polymer film/Aluminum foil/sealing layer. The sealing layer of the cold form laminate can be a heat seal lacquer (HSL) with a thickness of about = 0.5 µm, preferably a thickness of from about 4 µm to about 10.5 µm. In some embodiments, the sealing layer can be a polymeric film with a thickness of about = 4 µm made of polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof. Preferably, a polymeric film having a thickness of from about 4 µm to about 40 µm can be used as the sealing layer. By using a sealing layer of reduced thickness, the present disclosure achieves a laminate structure with excellent barrier to oxygen, moisture or both along with good physical characteristics. In various embodiments, the cold form laminate of the present disclosure can be used to form the base parts of blister packs for pharmaceutical products which are sensitive to moisture, oxygen or both.
The blister pack includes a blister base part formed from a cold form laminate according to the present disclosure and a lidding foil. The lidding foil can include an aluminum foil and a = 0.5 µm thick heat seal lacquer layer coated on a sealing side of the aluminum foil. Such blister pack with the cold form laminate of the present disclosure provides multifold better cross barrier to humidity and gases as compared to the blister packs with the cold form laminates having sealing layer(s) of regular thickness used conventionally.
[0015] 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
[0016] The following drawings form part of the present specification and are included to further illustrate aspects of the present disclosure. The disclosure may be better understood by reference to the drawings in combination with the detailed description of the specific embodiments presented herein.
[0017] Figure 1 is a representative cross-sectional view of conventional blister pack (100) showing passage of humidity and oxygen (110) in cavity through land area of sealing layer (120).
[0018] Figure 2 is a bar graph showing oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) in gram per cavity per day through lacquer sealing layer with thickness of 5.6 µm, PVC sealing layer with 15 µm thickness, PVC sealing layers with 30 µm thickness in accordance with an exemplary embodiments of the present disclosure in comparison with PVC sealing layer having 60 µm thicknesses as per the conventional cold form laminate.

DETAILED DESCRIPTION
[0019] The following is a detailed description of embodiments of the 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.
[0020] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0021] 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.
[0022] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, 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 and attached claims 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. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0023] 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.
[0024] 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.”
[0025] 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. All methods described herein can be performed in any 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 illustrate 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.
[0026] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability.
[0027] The description that follows, and the embodiments described therein, is provided by way of illustration of an example, or examples, of particular embodiments of the principles and aspects of the present disclosure. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the disclosure.
[0028] It should also be appreciated that the present disclosure can be implemented in numerous ways, including as a system, a method or a device. In this specification, these implementations, or any other form that the invention may take, may be referred to as processes. In general, the order of the steps of the disclosed processes may be altered within the scope of the invention.
[0029] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
[0030] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus, if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
[0031] Various terms as used herein are shown below. 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.
[0032] The term, “humidity” as used herein refers to moisture content in the surrounding atmosphere, which can be on the outside and inside of the cavity and used interchangeably with “moisture” and “water vapors”.
[0033] The terms, “oxygen”, “air”, and “gas” are used interchangeably herein and refer to air, gas or oxygen in the atmosphere.
[0034] The present disclosure relates to a cold form laminate comprising one or more sealing layer(s), for providing barrier to humidity, oxygen, or cross barrier to both. The cold form laminate is used as a base part for cavity forming of blister pack.
[0035] The present disclosure also relates to a blister pack with blister base part formed of cold form laminate comprising one or more sealing layer(s), and a lidding foil with one or more sealing layer(s), which may be the same or different from the cold form laminate, for providing barrier to humidity, oxygen, or cross barrier to both.
[0036] The standard cold forming laminate used conventionally includes 25 µm oriented polyamide (oPA) film/ 45 to 60 µm aluminum foil/sealing layer usually made of 60 µm or 100 µm PVC film. The Aluminum foil and PVC film are laminated with each other with the help of adhesive usually 3 to 5 µm thick layer. The standard laminate additionally includes 5.6 µm thick heat seal lacquer applied on the aluminum of lidding foil. Despite such construction, conventional cold forming laminates do not provide desired effective barrier to cross migration of humidity and oxygen requiring additional approaches like packing of the blister in a pouch with desiccant, including desiccant in a separate cavity or including desiccant in sealing layer, thus making the packaging costly, requiring additional packaging machine and/or additional equipment at blister machine.
[0037] The present disclosure addresses the aforementioned disadvantages by providing a cold forming laminate comprising one or more sealing layers, wherein the sealing layer is selected from a heat seal lacquer (HSL) with a thickness of about = 0.5 µm, and a polymeric film with a thickness of about = 4 µm. The polymeric film may be formed of any suitable polymer including, but not limited to, polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof.
[0038] In one embodiment, the present disclosure provides a cold forming laminate comprising a sealing layer made of a polymeric film with the reduced thickness in place of PVC layer used in the standard cold forming laminates.
[0039] In one particularly preferred embodiment, the present disclosure provides a cold forming laminate comprising the layer sequence: a polymer layer/oriented polymer film/Aluminum foil/sealing layer. In such construction of the cold forming laminate, the sealing layer is provided on the rear side of the aluminum foil, which is on the rear side of the oriented film, and the polymer layer is laminated on top of the oriented film. The oriented film can be selected from oriented film of polyamide, polyester, polypropylene, polyethylene or the like, and a combination thereof. In some embodiments, the oriented film can be a biaxially oriented film, for example, a biaxially oriented polyamide (BOPA) film, a biaxially oriented polypropylene film (BOPP), a biaxially oriented polyethylene terephthalate (BOPET), or a combination thereof. In one embodiment, the oriented film used is an oriented film of polyamide (oPA).
[0040] In an embodiment, an oriented film, for example an oriented film of polyamide of thickness of about 10 µm to about 40 µm, preferable about 15 µm to about 30 µm may be used in the cold form laminate.
[0041] In at least one embodiment, the polymer layer is a film of polymer selected from the group consisting of but not limited to polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof.
[0042] In an embodiment, the polymer layer can have a thickness of from about 4 µm to about 60 µm, preferably from about 15 µm to about 40 µm.
[0043] The polymer layer acts as stiffening layer to provide the stiffness or rigidity to the cold form laminate in accordance with present disclosure.
[0044] In an embodiment, an aluminum foil of thickness of about 25 µm to about 100 µm, preferably from about 40 µm to about 80 µm may be used in the cold form laminate.
[0045] According to embodiments of the present disclosure, the sealing layer can be selected from a material that is inert and does not react with the product to be packed inside the blister pack made from the cold forming laminate of the present disclosure. In at least one embodiment, the sealing layer of the cold form laminate can be a heat seal lacquer (HSL) with a thickness of about = 0.5 µm, preferably a thickness of from about 4 µm to about 10.5 µm. When the heat seal lacquer (HSL) is included as a first sealing layer on the inner side of the aluminum foil, the layer preceding the oriented film is of a film or extrusion coating of HSL to provide better stiffness of formed cavity.
[0046] In some embodiments, the sealing layer can be a polymeric film having a thickness of about = 4 µm made of polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof. Preferably, a polymeric film having a thickness of from about 4 µm to about 40 µm can be used as the sealing layer.
[0047] In some embodiments, the sealing layer can comprise a polymeric film having a thickness of about = 4 µm , preferably a thickness of about 4 µm to about 40 µm, and a heat seal laquer (HSL) with a thickness of about = 0.5 µm, preferably a thickness of from about 4 µm to about 10.5 µm. The polymeric film can be selected from a group consisting of but not limited to polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof.
[0048] Sealing layer, polymer layer, oriented polymer layer and aluminum foil of the cold forming laminate can be laminated or coated to the other layer, film, or foil, with the help of suitable adhesive or tie layer to provide minimum bonding strength of film to foil and film to film (inner and outer side).
[0049] The film or coating to provide a polymer layer on the oriented film can be of the same material or different as the sealing layer and in same or different thickness as sealing layer to achieve desired stiffness.
[0050] In one embodiment, the present disclosure provides a cold forming laminate comprising 15 µm PVC /25 µm oPA/ 45 µm Al/5.6 µm HSL.
[0051] In one embodiment, the present disclosure provides a cold forming laminate comprising 15 µm PVC /25 µm oPA/ 45 µm Al/4.0 µm HSL.
[0052] In one embodiment the present disclosure provides a cold forming laminate comprising 20 µm PE /25 µm oPA/ 60 µm Al/15 µm PCTFE.
[0053] In one embodiment, the present disclosure provides a cold forming laminate comprising 20 µm PET /25 µm oPA/ 45 µm Al/5.6 µm HSL.
[0054] In one embodime,nt the present disclosure provides a cold forming laminate comprising 30 µm PVC /25 µm oPA/ 45 µm Al/5.6 µm HSL.
[0055] In one embodiment, the present disclosure provides a cold forming laminate comprising 30 µm PVC /25 µm oPA/ 45 µm Al/15 µm PVC.
[0056] In one embodiment, the present disclosure provides a cold forming laminate comprising 30 µm PVC /25 µm oPA/ 45 µm Al/30 µm PVC.
[0057] In one embodiment, the present disclosure provides a cold forming laminate comprising 40 µm PVC /25 µm oPA/ 45 µm Al/5.6 µm HSL.
[0058] In some embodiments, the present disclosure provides a blister pack formed from a cold form laminate of the present disclosure for packing of products, especially those requiring protection from longer exposure of humidity and gas/air/oxygen, more particularly cross barrier to humidity and oxygen. The blister pack includes a blister base part made from a cold form laminate according to the present disclosure and a lidding foil. The lidding foil can include an aluminum foil and a = 0.5 µm thick heat seal lacquer layer coted on a sealing side of the aluminum foil. The lidding foil can be configured to open by tear, push through, rupture, peel, peel push or any suitable mechanism. Such blister pack with the cold form laminate of the present disclosure provides multifold better cross barrier to humidity and gases as compared to the blister packs with the cold form laminates having sealing layer(s) of regular thickness used conventionally.
[0059] The present disclosure is further explained in the form of following examples. However, it is to be understood that the examples are merely illustrative and are not to be taken as limitations upon the scope of the invention. Various changes and modifications to the disclosed embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the scope of the invention.
Methodology:
[0060] The oriented polymeric (oPA) film, with a polymeric film one side and an aluminium foil on the other side having thicknesses as mentioned below in the respective examples were laminated by means of an application of a layer of an adhesive at the rate of 4 g/m² between two films and the film and foil, further one or more sealing layer of HSL and/or polymeric layer was applied to provide the cold form laminate with constructions as mentioned below.
[0061] Blister packs were formed from the cold form laminates as per comparative Example A (standard conventional cold form laminate) as well as using cold form laminates in accordance with the present invention as per Examples 1a-1d and 2-5 as a base part for cavity forming and the same was sealed with a lidding foil of hard temper proof aluminum having a thickness of 28 µm, and coated with sealing layer of 5.6 µm heat seal lacquer for push through blister pack.
[0062] The water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) were studied of the blister packs made from the conventional standard cold form laminate as per Example A and the cold form laminates in accordance with the present disclosure as per Examples 1a-1d and 2-5. The WVTR and OTR were determined of the middle cavities and the edge cavities of blister packs having distance of 4 mm from the edge after 1 year, 2 years, 3 years and 4 years of packaging by calculating the values with a specially developed software. The input data for the transmission of oxygen and humidity were measured with standard test equipment, e.g. from company MOCON and the data were used for the calculation. The results of the WVTR and OTR determination studies are provided herein below is respective Tables
Example A
Conventional cold form laminate and blister pack formed therefrom
[0063] A standard blister pack was formed from the typical cold form laminate as a base part comprising of 25 µm of oriented polyamide (oPA) film, 40 µm aluminum, adhesive about 4 µm, and sealing layer including 60 µm PVC and 5.6 µm heat seal lacquer. This regular cold form laminate was sealed with a lidding foil of hard temper proof aluminum 28 µm with coating of sealing layer of 5.6 µm heat seal lacquer to form push through blister pack.
[0064] The WVTR and OTR were determined of the blister pack following the methods as described above under the “Methodology” section.
Example 1: Cold form laminate with 5.6 µm Heat seal lacquer (HSL) sealing layer
Table 1: Construction of cold form laminates in accordance with the present disclosure
Example Construction
1a 15µm PVC/ 25µm OPA/ 45µm Al / 5.6µm HSL
1b 30µm PVC/ 25µm OPA/ 45µm Al / 5.6µm HSL
1c 40µm PVC/ 25µm OPA/ 45µm Al / 5.6µm HSL
1d 20µm PET/ 25µm OPA/ 45µm Al / 5.6µm HSL
[0065] Cold form laminates with 5.6 µm Heat seal lacquer (HSL) sealing layer with constructions as per Examples 1a-1d in the above Table were prepared following the method disclosed in the “Methodology” section. Blister packs were prepared using these cold form laminates forming the base part of the blister pack and lidding aluminum foil coated with sealing layer of 5.6 µm heat seal lacquer. The WVTR and OTR were determined following the methods as described above under the “Methodology” section. Results of the WVTR and OTR determination studies are provided in below Table
Layer exposed to cross migration, WVTR & OTR:
[0066] Following are the details of the sealing layers which are exposed to the cross migration of moisture and gases (oxygen) and the respective WVTR & OTR:
(a) Table 2: Thickness in microns of the sealing layers exposed to the migration
Example A
(Regular cold form laminate) Examples 1a-1d (Present invention cold form laminates)
PVC 60 0
Adhesive 4 0
Heat seal lacquer 0 5.6
Total thickness 64.0 5.6

(b) Table 3: WVTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A
Middle cavity 0.1571 0.3142 0.4713 0.7855
Examples 1a-1d Middle cavity 0.0542 0.1084 0.1626 0.271
Example A
Edge cavity 0.2757 0.5514 0.8272 1.3786
Examples 1a-1d Edge cavity 0.0951 0.1903 0.2854 0.4757

(c) Table 4: OTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A
Middle cavity 0.0001 0.0004 0.0006 0.0009
Examples 1a-1d Middle cavity 0.0001 0.0003 0.0004 0.0007
Example A
Edge cavity 0.0002 0.0007 0.0011 0.0018
Examples 1a-1d Edge cavity 0.0002 0.0006 0.0009 0.0015

Example 2: Cold form laminate with sealing layer including 15 µm PCTFE (Aclar) &HSL
Table 5: Construction of cold form laminate in accordance with the present disclosure
Example Construction
2 20µm PE/ 25µm OPA/ 60µm Al / 15µm PCTFE (Aclar)
[0067] Cold form laminates with the construction as per the above Table was prepared following the method disclosed in the “Methodology” section. Blister pack was prepared using this cold form laminate forming the base part of the blister pack and lidding aluminum foil coated with sealing layer of 5.6 µm heat seal lacquer. The WVTR and OTR were determined following the methods as described above under the “Methodology” section. Results of the WVTR and OTR determination studies are provided in below Table

Layer exposed to cross migration, WVTR & OTR:
[0068] Following are the details of the sealing layers which are exposed to the cross migration of moisture and gases (oxygen) and the respective WVTR & OTR:
(a) Table 6: Thickness in microns of the sealing layers exposed to the migration
Example A
(Regular cold form laminate) Example 2(Present invention cold form laminates)
PVC 60 0
Aclar 0 15
Adhesive 4 4
Total thickness 64.0 19.0

(b) Table 7: WVTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.1571 0.3142 0.4713 0.7855
Example 2 Middle cavity 0.104 0.2081 0.3121 0.5202
Example A
Edge cavity 0.2757 0.5514 0.8272 1.3786
Example 2 Edge cavity 0.1826 0.3652 0.5478 0.913

(c) Table 8: OTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.0001 0.0004 0.0006 0.0009
Example 2 Middle cavity 0.0001 0.0002 0.0003 0.0005
Example A
Edge cavity 0.0002 0.0007 0.0011 0.0018
Example 2 Edge cavity 0.0001 0.0004 0.0006 0.001

Example 3: Cold form laminate with sealing layer including 15 µm PVC & HSL
Table 9: Construction of cold form laminate in accordance with the present disclosure
Example Construction
3 30µm PVC/ 25µm OPA/ 45µm Al / 15µm PVC
[0069] Cold form laminates with the construction as per the above Table was prepared following the method disclosed in the “Methodology” section. Blister pack was prepared using this cold form laminate forming the base part of the blister pack and lidding aluminum foil coated with sealing layer of 5.6 µm heat seal lacquer. The WVTR and OTR were determined following the methods as described above under the “Methodology” section. Results of the WVTR and OTR determination studies are provided in below Table
Layer exposed to cross migration, WVTR & OTR:
[0070] Following are the details of the sealing layers which are exposed to the cross migration of moisture and gases (oxygen) and the respective WVTR & OTR:
(a) Table 10: Thickness in microns of the sealing layers exposed to the migration
Example A
(Regular cold form laminate) Example 3 (Present invention cold form laminates)

PVC 60 15
Adhesive 4 4
Total thickness 64 19.0

(b) Table 11: WVTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.1571 0.3142 0.4713 0.7855
Example 3 Middle cavity 0.1172 0.2343 0.3515 0.5859
Example A
Edge cavity 0.2757 0.5514 0.8272 1.3786
Example 3 Edge cavity 0.2057 0.4113 0.617 1.0283

(c) Table 12: OTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.0001 0.0004 0.0006 0.0009
Example 3 Middle cavity 0.0001 0.0002 0.0003 0.0006
Example A
Edge cavity 0.0002 0.0007 0.0011 0.0018
Example 3 Edge cavity 0.0001 0.0004 0.0007 0.0011

Example 4: Cold form laminate with sealing layer including 30 µm PVC & HSL
Table 13: Construction of cold form laminate in accordance with the present disclosure
Example Construction
4 30µm PVC/ 25µm OPA/ 45µm Al / 30µm PVC

[0071] Cold form laminates with the construction as per the above Table was prepared following the method disclosed in the “Methodology” section. Blister pack was prepared using this cold form laminate forming the base part of the blister pack and lidding aluminum foil coated with sealing layer of 5.6 µm heat seal lacquer. The WVTR and OTR were determined following the methods as described above under the “Methodology” section. Results of the WVTR and OTR determination studies are provided in below Table
Layer exposed to cross migration, WVTR & OTR:
[0072] Following are the details of the sealing layers which are exposed to the cross migration of moisture and gases (oxygen) and the respective WVTR & OTR:
(a) Table 14: Thickness in microns of the sealing layers exposed to the migration
Example A
(Regular cold form laminate) Example 4 (Present invention cold form laminates)
PVC 60 30
Adhesive 4 4
Total thickness 64.0 34.0

(b) Table 15: WVTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.1571 0.3142 0.4713 0.7855
Example 4 Middle cavity 0.1305 0.261 0.3914 0.6524
Example A
Edge cavity 0.2757 0.5514 0.8272 1.3786
Example 4 Edge cavity 0.229 0.458 0.687 1.145

(c) Table 16: OTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.0001 0.0004 0.0006 0.0009
Example 4 Middle cavity 0.0001 0.0003 0.0004 0.0007
Example A
Edge cavity 0.0002 0.0007 0.0011 0.0018
Example 4 Edge cavity 0.0001 0.0005 0.0008 0.0013

Example 5: Cold form laminate with 4 µm Heat seal lacquer sealing layer
Table 17: Construction of cold form laminate in accordance with the present disclosure
Example Construction
5 15µm PVC/ 25µm OPA/ 45µm Al / 4.0µm HSL

[0073] Cold form laminates with the construction as per the above Table was prepared following the method disclosed in the “Methodology” section. Blister pack was prepared using this cold form laminate forming the base part of the blister pack and lidding aluminum foil coated with sealing layer of 5.6 µm heat seal lacquer. The WVTR and OTR were determined following the methods as described above under the “Methodology” section. Results of the WVTR and OTR determination studies are provided in below Table
Layer exposed to cross migration, WVTR & OTR:
[0074] Following are the details of the sealing layers which are exposed to the cross migration of moisture and gases (oxygen) and the respective WVTR & OTR:
(a) Table 18: Thickness in microns of the sealing layers exposed to the migration
Example A
(Regular cold form laminate) Example 5 (Present invention cold form laminates)
PVC 60 0
Adhesive 4 0
Heat seal lacquer 0 4
Total thickness 64.0 4.0

(b) Table 19: WVTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.1571 0.3142 0.4713 0.7855
Example 5 Middle cavity 0.0465 0.0929 0.1394 0.2323
Example A
Edge cavity 0.2757 0.5514 0.8272 1.3786
Example 5 Edge cavity 0.0816 0.1631 0.2447 0.4078

(c) Table 20: OTR (g/cavity)
For edge distance: 4 mm
After 1 year After 2 year After 3 year After 4 year
Example A Middle cavity 0.0001 0.0004 0.0006 0.0009
Example 5 Middle cavity 0.0001 0.0003 0.0004 0.0006
Example A
Edge cavity 0.0002 0.0007 0.0011 0.0018
Example 5 Edge cavity 0.0001 0.0005 0.0007 0.0012

[0075] Cold forming laminate comprising a sealing layer with much less thickness as compared to the conventional cold forming laminates having PVC as sealing layer with 60 µm thickness unexpectedly shows much better barrier to humidity and oxygen as can be seen from Fig. 2. Replacement of PVC sealing layer having 60 µm thickness with PVC sealing layer having 15 µm thickness surprisingly resulted in 1.4 times better barrier. Replacement of PVC sealing layer having 60 µm thickness with HSL layer having 5.6 µm thickness unexpectedly resulted in 2.5 times better barrier against humidity. Similar barrier to oxygen can be observed in Fig. 2.
[0076] Cold forming laminate comprising polymer layer in the form of a polymer film and sealing layer and Al foil on top of the oriented film shows better stiffness as compared to a laminate without such polymer layer acting as stiffening layer as evident from the below Table 21:
Table 21: Increasing stiffness (%)
Structure Stiffness (%)
25 µm oPA/ 45 µm Al/15 µm PVC 100
30 µm PVC /25 µm oPA /45 µm Al/15 µm PVC 153
60 µm PVC /25 µm oPA /45 µm Al/15 µm PVC 253

[0077] The cold forming laminates provided in accordance with the present disclosure comprising one or more sealing layer(s) provide requisite stiffness, better flatness, aids ease in transportation, reduces the tendency of delamination and denting of cavities of blister pack during logistics. The yield that is area per unit weight of cold forming laminate despite being multilayer is not adversely impacted. The cold forming laminate provided in accordance with the present disclosure advantageously provides better barrier properties related to cross migration of humidity and gases, especial oxygen, as well as physical characteristics rendering it overall suitable for forming base part of blister pack.
[0078] 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:1. A cold form laminate for producing a base part of a blister pack, the laminate comprises the layer sequence:
polymer layer/oriented polymer film/Aluminum foil/sealing layer.
2. The laminate as claimed in claim 1, wherein the sealing layer is a heat seal lacquer layer having a thickness of = 0.5 µm, or a polymeric film having a thickness of = 4 µm.
3. The laminate as claimed in claim 1, wherein the sealing layer is a heat seal lacquer layer having a thickness of from 4 µm to 10.5 µm.
4. The laminate as claimed in claim 1, wherein the sealing layer is a polymeric film having a thickness of from 4 µm to 40 µm.
5. The laminate as claimed in claim 4, wherein the polymeric film is selected from the group consisting of polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof.
6. The laminate as claimed in claim 1, wherein the polymer layer is a film of polymer selected from the group consisting of polyvinyl chloride (PVC), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE), polypropylene, polyester, cyclo olefinic copolymer, cyclo olefinic polymer, polychlorotrifluoroethylene (PCTFE), or a combination thereof.
7. The laminate as claimed in claim 1, wherein the oriented polymer film is selected from the group consisting of polyamide, polyester, polypropylene, polyethylene, or a combination thereof.
8. The laminate as claimed in claim 1, wherein the oriented film is a biaxially oriented polyamide (BOPA) film, a biaxially oriented polypropylene (BOPP) film, a biaxially oriented polyethylene terephthalate (BOPET) film, or a combination thereof.
9. The laminate as claimed in claim 1, wherein the oriented film is an oriented polyamide (oPA) film.
10. The laminate as claimed in claim 1, wherein the polymer layer has a thickness of from 4 µm to 60 µm.
11. The laminate as claimed in claim 1, wherein the polymer layer has a thickness of from 15 µm to 40 µm.
12. The laminate as claimed in claim 1, wherein the oriented film has a thickness of from 10 µm to 40 µm.
13. The laminate as claimed in claim 1, wherein the oriented film has a thickness of from 15 µm to 30 µm.
14. The laminate as claimed in claim 1, wherein the aluminum foil has a thickness of from 25 µm to 100 µm.
15. The laminate as claimed in claim 1, wherein the aluminum foil has a thickness of from 40 µm to 80 µm.
16. A blister pack comprising:
a blister base part produced from a cold form laminate as claimed in any of claims 1 to 15; and
a lidding foil.
17. The blister pack as claimed in claim 16, wherein the lidding foil comprises an aluminum foil and a heat seal lacquer layer coated on a sealing side of the aluminum foil.
18. The blister pack as claimed in claim 17, wherein the heat seal lacquer layer has a thickness of = 0.5 µm.