Packaging materials for plastic surgery

Abstract

The present invention provides a packaging material comprising a first layer formed from a thermoplastic polyurethane (TPU) and a second layer formed from a heat-activatable olefin-based polymer coupling agent containing an ethylene-vinyl acetate (EVA) copolymer and a second polar comonomer, the packaging material having a total thickness of 2 mils (50 μm) to 24 mils (600 μm), the first layer having a thickness of 0.8 mils (20 μm) to 16 mils (400 μm), and the second layer having a thickness of 0.8 mils (20 μm) to 8 mils (200 μm). The packaging material of the present invention can be used to provide thermoformed containers and trays for storing sharp, abrasive articles such as orthopedic devices, including bone implants.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates generally to packaging, and in particular to packaging materials for sharp, abrasive articles such as orthopedic implants. [Background technology]

[0002] Orthopedic implants have extremely sharp edges to ensure minimal tolerances during surgical placement. Packaging such sharp objects presents challenges as the sharp edges can create debris from contact and abrasion of the packaging material. Surgical implants are typically packaged in plastic bags for transport from the manufacturer to the hospital for implantation.

[0003] The packaging bag must be durable enough on the outside to prevent punctures, exhibit adequate barrier properties to control oxygen and moisture transmission, and be resistant to contaminants such as bacteria. Tensile strength is required to resist bursting, tearing, and cutting over a wide temperature range. This allows for a resilient product, which is desirable for all applications where there is a risk of abrasion.

[0004] Composite structures made from established materials are known in the art, most commonly consisting of a bladder made from PET-G for rigidity and dimensional stability and thermoplastic polyurethane for excellent surface abrasion resistance.

[0005] Challenges to overcome in producing such packaging include, for example, the additional handling of PET-G blisters with separate pouches, including increased raw material input. This results in high manufacturing costs for the additional pouches as well as high costs for manual assembly of the packaging. It can also create difficulties for in-hospital users, such as nurses / end users who need to handle multiple parts during surgery. While nested blister packaging offers some benefits, it still has high processing costs because two different materials and two separate tools are required for thermoforming and deep drawing. The same concerns apply equally to nested PET-G blisters with alternative materials such as silicone. In either case, there is still a risk of the implant slipping and damaging the packaging.

[0006] Medical device packaging materials must also exhibit the appropriate barrier properties required to maintain the proper composition of the bodily fluids with which they interact and ensure that oxygen, moisture, and potential contaminants cannot penetrate through the film or tube. Such packaging, despite its rigidity, must also be durable to withstand the rigors and fast pace of the medical environment. Finally, it is desirable for medical device packaging to exhibit a clear history of biocompatibility.

[0007] Multilayer medical packaging made from elastomeric TPU films combined with PET-G films is available in the art and has been used to package orthopedic implants. Examples include grades such as Covestro's BAYFOL MA502 or MA504, all of which exhibit excellent performance. Such structured films offer higher strength and durability and have proven suitable for form-fill-seal (FFS) packaging on highly automated lines. Summary of the Invention [Problem to be solved by the invention]

[0008] Nevertheless, those skilled in the art continue to search for solutions that provide better adhesion between the various layers. A combination of cheaper material economy and technically superior material performance is desired.

[0009] There continues to be a need in the art for methods to overcome the lack of adhesion between incompatible polymers. [Means for solving the problem]

[0010] Thus, the present invention provides composite film structures with improved adhesion of thermoplastic polyurethane (TPU) to a variety of target thermoforming materials intended for lamination. Such laminates can then be thermoformed into containers and trays to package abrasive sharp medical articles such as orthopedic devices, including bone implants.

[0011] These and other advantages and benefits of the present invention will be apparent from the detailed description of the invention that follows.

[0012] The present invention will now be described, by way of illustration and not limitation, in conjunction with the drawings. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a cross-sectional view of a packaging material of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will now be described for purposes of illustration and not limitation. Except in the operating examples or where otherwise indicated, all numbers expressing quantities, percentages, and the like herein are understood to be modified in each instance by the term "about."

[0015] Additionally, any numerical range recited herein is intended to include all subranges of the same numerical precision subsumed within the recited range. For example, a range of "1.0 to 10.0" is intended to include all subranges between (and including) the recited minimum value of 1.0 and the recited maximum value of 10.0, i.e., subranges having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein, and any minimum numerical limitation recited herein is intended to include all higher numerical limitations subsumed therein. Accordingly, applicants reserve the right to amend this specification, including the claims, to explicitly recite any subranges subsumed within the ranges expressly recited herein. All such ranges are intended to be inherently described herein, such that amending to explicitly recite any such subranges complies with the requirements of 35 U.S.C. § 112(a) and § 132(a). The various embodiments disclosed and described herein may comprise, consist of, or consist essentially of the features and characteristics as variously described herein.

[0016] Any patent, publication, or other disclosure material identified herein is incorporated herein by reference in its entirety, unless otherwise stated, but only to the extent that the incorporated material does not contradict existing definitions, statements, or other disclosure material expressly set forth herein. Accordingly, to the extent necessary, the explicit disclosure set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated herein by reference but that contradicts existing definitions, statements, or other disclosure material set forth herein is incorporated only to the extent that no conflict arises between the incorporated material and the existing disclosure material. Applicant reserves the right to amend this specification to explicitly recite any subject matter, or portion thereof, incorporated herein by reference.

[0017] Throughout this specification, references to "various non-limiting embodiments," "certain embodiments," and the like mean that particular features or characteristics can be included in certain embodiments. Thus, the use of phrases such as "various non-limiting embodiments," "in certain embodiments," and the like herein does not necessarily refer to a common embodiment, but may refer to different embodiments. Furthermore, particular features or characteristics may be combined in any suitable manner in one or more embodiments. Thus, particular features or characteristics illustrated or described in connection with various or certain embodiments can be combined, in whole or in part, with features or characteristics of one or more other embodiments without limitation. Such modifications and variations are intended to be within the scope of this specification.

[0018] As used herein, the grammatical articles "a," "an," and "the" are intended to include "at least one" or "one or more," unless otherwise specified, even if "at least one" or "one or more" is explicitly used in a particular instance. As such, these articles are used herein to refer to one or more than one (i.e., "at least one") of the grammatical object of the article. By way of example and without limitation, "a component" means one or more components, and thus, more than one component is conceivable and may be employed or used in the practice of the described embodiments. Furthermore, unless otherwise specified in the context of the usage, the use of a singular noun includes the plural, and the use of a plural noun includes the singular.

[0019] In one aspect, the present invention relates to a packaging material comprising a first layer formed from a thermoplastic polyurethane (TPU) and a second layer formed from a heat-activatable olefin-based polymer coupling agent containing at least an ethylene-vinyl acetate (EVA) copolymer and a second polar comonomer, the packaging material having a total thickness of from 2 mils (50 μm) to 24 mils (600 μm), the first layer having a thickness of from 0.8 mils (20 μm) to 16 mils (400 μm), and the second layer having a thickness of from 0.8 mils (20 μm) to 8 mils (200 μm).

[0020] Thermoplastic polyurethanes (TPUs) are well known in the art for their abrasion-resistant properties. TPUs are robust materials, and TPU products exhibit high tear strength and resistance, durability even in soft grades, good chemical resistance, desirable clarity, significant abrasion resistance, and excellent low-temperature performance. Packaging solutions are provided, including nested blister packs and composite blister packs.

[0021] Thermoplastic polyurethane (TPU) is an ideal material for use in the construction of various medical devices, such as tubing and fluid collection bags, due to its customizability. Because medical supplies often need to deliver drugs, blood, or other bodily fluids, the materials used in their development must not exude any harmful substances that could leach into these fluids and compromise their integrity, making the safety of TPU products for use on or within the body important. The combination of materials does not have to be done in a single process. Lamination of materials is the preferred method for obtaining thermoformable products for subsequent thermoforming or FFS packaging.

[0022] New packaging designs may combine the mechanical puncture and abrasion resistance of TPU elastomers with the thermoformability of rigid polymers, such as polyethylene terephthalate glycol (PETG), cycloolefin copolymers (COC), or polyolefins, such as cross-linked polyethylene (PE) foam. This can be done by forming laminates of separate materials and customizing these laminates with a thermoforming process. When these layers are consistently and reliably bonded, they can be formed together into specific shapes that address the need to hold orthopedic medical implants securely in place. Such user-friendly designs help avoid more complex packaging structures consisting of a separate sleeve or pouch of abrasion-resistant layers and a rigid thermoformed outer box.

[0023] Thermoplastic polyurethane (TPU) formulations can be tailored to meet the requirements of medical industry use. No plasticizers are required in TPU manufacturing, eliminating harmful by-products. TPU is known for its reliability in the medical field, and its formulations have previously been proven biocompatible.

[0024] Ease of sealing is required to ensure the longevity of medical articles. Such sealing techniques, such as ultrasonic and solvent bonding, can provide consistent weld quality more efficiently than other conventional methods. The use of these sealing techniques with thermoplastic polyurethanes (TPUs) is well known to those skilled in the art.

[0025] As shown in FIG. 1, the packaging material according to the present invention comprises a first layer 1 made of thermoplastic polyurethane (TPU) and a second layer 2 containing modified ethylene vinyl acetate (EVA).

[0026] In certain embodiments, the second layer 2 comprises a TPU-modified EVA copolymer made by blending both TPU and EVA, which improves bonding to dissimilar polymers. This blending approach provides excellent bonding properties to both TPU and rigid thermoforming polymers. In these embodiments, the packaging material according to the present invention has at least one layer of a TPU / EVA blend.

[0027] The second layer 2 also contains a polar comonomer, such as that disclosed in U.S. Patent No. 5,593,775. Ethylene is preferred as the comonomer. In the packaging material according to the present invention, at least two different polar oxygenated olefin copolymers A and B are mixed and melted together under sufficient shear. In various embodiments, the total proportion of polar oxygenated comonomer units is 18 wt% to 40 wt%, based on the total weight of the polymer resin used. The olefin comonomer A is preferably present in a higher amount, with the total proportion being at least 60% of the total weight of the comonomer units. In certain embodiments, the comonomers used in the polar olefin copolymers A and B are methacrylic acid and / or its salts and / or esters, in unsaponified and / or saponified form, and / or acrylic acid and / or its salts and / or esters, and / or vinyl acetate.

[0028] In some embodiments, TPU ether-based films are preferred over TPU ester-based films due to the improved hydrolysis resistance of TPU ether-based films.

[0029] Furthermore, coextrusion production of films with a simple TPU layer on one surface and at least one TPU / EVA layer on the other surface for bonding purposes improves the performance of the packaging material of the present invention. The coextrusion process provides further bridging options when combined with additional layers. Such coextruded films are particularly suitable for flame welding to cross-linked polyethylene (PE) foam. Surface-modified PE foam is known in the art to be suitable for packaging medical devices, particularly those intended for surgical implants.

[0030] Adhesive-modified EVA provides improved adhesion between the TPU and the structured olefin surface. Adhesion can be introduced by inserting an adhesive layer between the TPU and the olefin or by blending the TPU with the olefin. In certain embodiments, this can be achieved by blending the TPU with the EVA and providing a bridge layer that combines compatibility with the TPU surface layer.

[0031] Olefinic materials suitable for use in the present invention include, but are not limited to, polyethylene (e.g., high density HDPE, low density LDPE, and linear low density LLDPE), polypropylene, polymethylpentene, polyisobutylene, polybutylene, and ethylene propylene diene monomer (EPDM) rubber.

[0032] The adhesiveness of the second layer 2 exhibits optimal performance at a TPU / EVA blend ratio of 0.3% to 3.0% by mass. In a specific embodiment, the blend ratio of TPU to modified EVA is 0.7% to 1.5% by mass.

[0033] TPU and EVA are available in thermoplastic technology due to a bonding processing window, making them suitable partners for enhancing adhesion. The use of a bonding thermoplastic window can be implemented in film extrusion processes, allowing for the co-extrusion of various layers.

[0034] In some embodiments, EVA-maleic anhydride (MSA) terpolymers can be selected. These polymers can be randomly copolymerized, or in some embodiments, the MSA can be grafted onto the EVA backbone. Certain embodiments of the packaging material of the present invention have at least two layers: one TPU layer 1, which provides abrasion resistance, and one TPU / EVA blend layer 2, which provides adhesion.

[0035] In certain embodiments, the coupling material resin used in the second layer 2 contains ethylene, vinyl acetate, and maleic anhydride as comonomers, with the total amount of maleic anhydride not exceeding 5000 ppm.

[0036] The first layer 1 of the packaging material according to the invention comprises at least one TPU elastomer, preferably a linear TPU elastomer, in which the longer chain diol component is a polyester or polyether, preferably having a Shore hardness measured according to ASTM D 2240 of 75A to 95A. TPU ether based films are preferred over TPU ester based films due to the improved hydrolysis resistance of TPU ether based films.

[0037] Suitable thermoplastic polyurethanes are available from various commercial suppliers under the trade names DESMOPAN, ELASTOLLAN, ESTANE, MORTHANE and TEXIN.

[0038] Packaging materials according to various embodiments of the present invention may contain additional processing additives in the first layer 1, such as: a) antiblocking agents, inorganic or organic spacers, b) lubricating or separating aids, usually surface active; c) pigments or fillers, and d) Stabilizers. The sum of additives a, b, c, and d in selected embodiments is between 0% and 30%, and in certain embodiments, the sum is greater than 0% to 30%.

[0039] In various embodiments, the film has a total thickness of 2 mils (50 μm) to 24 mils (600 μm). In these embodiments, the first (TPU) layer 1 has a thickness of 0.8 mils (20 μm) to 16 mils (400 μm), and the second (blend) layer 2 has a gauge of 0.8 mils (20 μm) to 8 mils (200 μm).

[0040] Known thermoforming procedures for processing plastic materials can be used to produce multilayer structures such as packaging materials. Coextrusion techniques are preferred, particularly to achieve better levels of bond strength between layers at temperatures between 160°C and 200°C. Blown film coextrusion is a particularly preferred method for making packaging materials according to the present invention.

[0041] In the manufacture of the packaging material of the present invention, the film may be subjected to a surface treatment such that at least one of the outer layers of the packaging material is subjected to a chemical or physical treatment.

[0042] The packaging materials according to the invention can be used to manufacture containers (e.g. bags, trays, etc.) for sharp and abrasive articles by lamination to a rigid plastic material followed by thermoforming. They offer the advantage of being compatible with a variety of thermal and solvent-based sealing methods. The packaging materials according to the invention are particularly advantageous for packaging sharp and abrasive articles such as medical, especially orthopedic, implants. [Example]

[0043] The following non-limiting and non-exhaustive examples are intended to further illustrate various non-limiting and non-exhaustive embodiments without limiting the scope of the embodiments described herein. All amounts given in "parts" and "%" are understood to be by weight unless otherwise specified.

[0044] The following examples and comparative examples were produced by blown film extrusion. Suitable extrusion processes for processing thermoplastic materials are described in particular in Wortberg, Mahlke and Effen, Kunststoffe, 84 (1994) 1131-1138, Pearson, Mechanics of Polymer Processing, Elsevier Publishers, New York, 1985, and Davis-Standard, Paper, Film & Foil Converter, 64 (1990) pp 84-90. Blown film tooling for forming a melt into a film is described in Rauwendaal, Polymer Extrusion, Hanser Publishers, New York, 1986, and Michaeli in: Extrusions-Werkzeuge, Hanser Verlag, Munich, 1991.

[0045] Example 1 A two-layer blown film die was used to produce coextruded films with a first layer formed from a TPU-ether having a Shore A hardness of 89 measured according to ASTM D2240, corresponding to a Shore D hardness of 36. The TPU-ether had a melt flow index (MFI) of 25 g / 10 min at 190 °C / 21.6 kg according to ISO 1133-1 and a melt flow index of 1.12 g / cm according to ISO 1183-1. 3 The 100 μm layer had a specific gravity of 1.04 μm and a thermomechanical analysis (TMA) onset temperature of 165° C. The 100 μm layer contained processing additives: 2.5% diatomaceous earth and 0.3% amide wax. All components of this first layer were processed in a single extruder.

[0046] The second layer has a melt flow index (MFI) of 3.5 g / 10 min at 230 °C / 2.16 kg according to ISO 1133-1 and a modulus of 0.94 g / cm according to ISO 1183-1. 3The resin was an ethylene-vinyl acetate copolymer having a specific gravity of 1000 ppm to which maleic anhydride had been grafted. The vinyl acetate (VA) content of the resin was 28% by weight, and the maleic anhydride content was less than 4000 ppm. The Shore hardness according to ASTM D2240 was 80A / 27D. The TMA onset temperature was 75°C. The second layer had a thickness of 50 μm.

[0047] The extrusion tool was set at a temperature of 160°C to 200°C. The two melt streams were joined in a two-layer blown film die at a processing temperature of 195°C and extruded through a circular die with a diameter of 130 mm. The circular melt was cooled by blowing cold air. The film was subsequently broken, flattened, separated, and wound up.

[0048] Example 2 A two-layer blown film die was used to produce coextruded films, with the first layer formed from a TPU-ether having a Shore A hardness of 89 measured according to ASTM D2240, corresponding to a Shore D hardness of 36. The TPU-ether had a melt flow index (MFI) of 25 g / 10 min at 190 °C / 21.6 kg according to ISO 1133-1 and a melt flow index of 1.12 g / cm according to ISO 1183-1. 3 The 90 μm layer had a specific gravity of 1.00 and a TMA onset temperature of 165° C. The 90 μm layer contained processing additives: 2.5% diatomaceous earth and 0.3% amide wax. All components of this first layer were processed in a single extruder.

[0049] The second layer has a melt flow index (MFI) of 25 at 190°C / 21.6 kg per ISO 1133-1, a Shore A hardness of A89 / D36 per ASTM D2240, and a hardness of 1.12 g / cm per ISO 1183-1. 3 The blend was a 50 wt% TPU-ether blend with a specific gravity of 1.0 g / 10 min at 230°C / 2.16 kg according to ISO 1133-1 and a TMA onset temperature of 165°C. The 50 wt% TPU-ether blend had a melt flow index (MFI) of 3.5 g / 10 min at 230°C / 2.16 kg according to ISO 1133-1 and a TMA onset temperature of 0.94 g / cm according to ISO 1183-1. 3The resin was a grafted ethylene-vinyl acetate / maleic anhydride copolymer having a specific gravity of 1000 ppm. The vinyl acetate content of the resin was 28% by weight, and the maleic anhydride content was less than 4000 ppm. The Shore hardness according to ASTM D2240 was 80A / 27D. The TMA onset temperature was 75°C. The second layer had a thickness of 60 μm.

[0050] The extrusion tool was set at a temperature of 160°C to 200°C. The two melt streams were joined in a two-layer blown film die at a processing temperature of 195°C and extruded through a circular die with a diameter of 130 mm. The circular melt was cooled by blowing cold air. The film was subsequently broken, flattened, separated, and wound up.

[0051] Comparative Example 1 A single-layer blown film die was used to produce films from the TPU-ether, which had a Shore A hardness of 89 measured according to ASTM D2240, corresponding to a Shore D hardness of 36. The TPU-ether had a melt flow index (MFI) of 25 g / 10 min at 190 °C / 21.6 kg according to ISO 1133-1 and a melt flow index of 1.12 g / cm according to ISO 1183-1. 3 The 150 μm layer had a specific gravity of 1.001 μm and a TMA onset temperature of 165° C. The 150 μm layer contained processing additives: 2.5% diatomaceous earth and 0.3% amide wax. All components of this layer were processed in a single extruder.

[0052] The extruder was operated at a temperature of 160°C to 200°C. The melt stream was introduced into a blown film die at a processing temperature of 195°C and extruded through a 130 mm diameter lip set. The circular melt was cooled by blowing cold air. The film was subsequently broken, flattened, separated, and wound up.

[0053] Comparative Example 2 A two-layer blown film die was used to produce coextruded films consisting of a layer formed from a TPU-ester with a Shore A hardness of 90 measured according to ASTM D2240, corresponding to a Shore D hardness of 40. The TPU-ester had a melt flow index (MFI) of 60 g / 10 min at 190 °C / 21.6 kg according to ISO 1133-1 and a melt flow index of 1.22 g / cm according to ISO 1183-1. 3 The 30 μm layer had a specific gravity of 1000 μm and a TMA onset temperature of 170° C. The 30 μm layer contained processing additives: 5% diatomaceous earth and 1% amide wax. All components of this layer were processed in a single extruder.

[0054] The second layer was made from an essentially linear hydroxyl polyester polyurethane. This highly crystalline, flexible hot melt adhesive polyurethane typically has excellent adhesion to many materials. Flat extruded products made from this raw material are known for their high quality. This TPU-ester has a viscosity of 1200 mPas measured according to ISO 3219 and a viscosity of 1.16 g / cm according to ISO 1183-1. 3 , a Shore A hardness according to ASTM D2240 of A94 / D45, and a TMA onset temperature of 55° C. The second layer had a thickness of 20 μm.

[0055] The extrusion tool was set at a temperature of 130°C to 180°C. The melt streams were joined in a multilayer blown film die at a processing temperature of 180°C and extruded through a set of circular lips with a diameter of 300 mm. The circular melt was cooled by blowing cold air. The film was then broken, flattened, separated, and wound up.

[0056] Comparative Example 3 A single-layer blown film die was used to produce films from the TPU-ester with a Shore A hardness of 90 measured according to ASTM D2240, which corresponds to a Shore D hardness of 39. The TPU-ester had a melt flow index (MFI) of 16 g / 10 min at 190 °C / 8.7 kg according to ISO 1133-1 and a melt flow index of 1.19 g / cm according to ISO 1183-1. 3 The 130 μm layer had a specific gravity of 1.5% and a TMA onset temperature of 162° C. The 130 μm layer contained processing additives: 1.5% diatomaceous earth and 0.4% amide wax. All components of this layer were processed in a single extruder.

[0057] The extruder was operated at a temperature of 160°C to 190°C. The melt stream was introduced into a blown film die at a processing temperature of 185°C and extruded through a 130 mm diameter lip set. The circular melt was cooled by blowing cold air. The film was subsequently broken, flattened, separated, and wound up.

[0058] In assessing the properties of the inventive and comparative samples, adhesion to polyethylene, both direct and during thermoforming, was considered an important characteristic. Bond strength to olefin layers was tested between the films prepared as samples and comparative samples.

[0059] Lamination of the sample and comparative films was performed using a HOTRONIX laminator. The films were laminated to a 0.0045 in. / 115 μm thick polyethylene (PE) film. PE has a melt flow index (MFI) of 0.4 g / 10 min at 190°C and 2.16 kg per ISO 1133-1 and 0.92 g / cm per ISO 1183-1. 3 and a Shore hardness of 45D / 94A. The PE film had a TMA initiation temperature of 103°C. Lamination was performed at 150°C for 10 seconds.

[0060] Visual interpretation of manual separation and pull test results with a test device were determined.

[0061] For pull testing, 1 inch / 25.4 mm wide sample strips were cut from the laminate using a parallel blade sample cutter. Separation force was determined using the normal sample clamp and load cell of the tensile test setup.

[0062] To obtain the thermoforming results, blanks approximately 125 mm in diameter were cut from the laminate and heated using a MINISTAR S thermoforming device. The blanks were heated in an infrared (IR) field for approximately 20 seconds and then drawn into a cylindrical round-bottom shape (75 mm height and 75 mm diameter).

[0063] The results of the examples detailed above are summarized in Table I.

[0064] [Table 1]

[0065] As can be seen by looking at Table I, the films made in accordance with the present invention are superior to the comparative films.

[0066] This specification has been described with reference to various non-limiting and non-exhaustive embodiments. However, those skilled in the art will recognize that various substitutions, modifications, or combinations of any of the disclosed embodiments (or portions thereof) may be made within the scope of this specification. Accordingly, it is intended and understood that this specification supports additional embodiments not expressly set forth herein. Such embodiments may be obtained, for example, by combining, modifying, or rearranging any of the disclosed steps, components, elements, features, aspects, properties, limitations, etc., of the various non-limiting embodiments described herein. In this manner, applicants reserve the right to amend the claims during prosecution to add features variously described herein, and such amendments are subject to the requirements of 35 U.S.C. § 112(a) and 35 U.S.C. § 132(a).

[0067] Various aspects of the subject matter described herein are presented in the following numbered sections:

[0068] Item 1. A packaging material comprising a first layer formed from a thermoplastic polyurethane (TPU) and a second layer formed from a heat-activatable olefin-based polymer coupling agent containing an ethylene-vinyl acetate (EVA) copolymer and a second polar comonomer, the packaging material having a total thickness of 2 mils (50 μm) to 24 mils (600 μm), the first layer having a thickness of 0.8 mils (20 μm) to 16 mils (400 μm), and the second layer having a thickness of 0.8 mils (20 μm) to 8 mils (200 μm).

[0069] Item 2. The packaging material of item 1, wherein the first layer comprises a TPU-ether.

[0070] Item 3. The packaging material according to any one of Items 1 and 2, wherein the first layer has a Shore hardness of 75A to 95A measured in accordance with ASTM D 2240.

[0071] Item 4. The packaging material according to any one of items 1 to 3, wherein the second layer is a blend comprising thermoplastic polyurethane (TPU) and ethylene-vinyl acetate (EVA) copolymer.

[0072] Item 5. The packaging material according to any one of Items 1 to 4, wherein the ethylene-vinyl acetate (EVA) copolymer contains at least 15% vinyl acetate.

[0073] Item 6. The packaging material according to any one of Items 1 to 5, wherein the olefin-based polymer coupling agent contains less than 5000 ppm of maleic anhydride.

[0074] Item 7. The packaging material according to any one of Items 1 to 6, wherein the second layer comprises a blend of thermoplastic polyurethane (TPU) and modified ethylene-vinyl acetate (EVA) in a ratio of 0.3% to 3.0% by mass.

[0075] Item 8. The packaging material according to any one of items 1 to 7, wherein the second layer comprises a blend of thermoplastic polyurethane (TPU) and modified ethylene-vinyl acetate (EVA) in a ratio of 0.7% to 1.5% by mass.

[0076] Item 9. The packaging material according to any one of Items 1 to 8, wherein the second polar comonomer comprises one or more comonomers selected from the group consisting of vinyl acetate, acrylic acid, acrylic acid esters, acrylic acid salts, methacrylic acid, methacrylic acid esters, and methacrylic acid salts.

[0077] Item 10. The packaging material according to any one of Items 1 to 9, wherein 0% to 30% of an additive selected from the group consisting of an antiblocking agent, an inorganic or organic spacer, a lubricating or separation aid, a pigment, a filler, and a stabilizer is added to the first layer.

[0078] Item 11. The packaging material according to any one of Items 1 to 10, which is produced by a coextrusion process at a temperature of 160°C to 200°C.

[0079] Item 12. The packaging material according to any one of Items 1 to 10, which is produced by a blown film coextrusion process at a temperature of 160°C to 200°C.

[0080] Item 13. The packaging material according to any one of Items 1 to 12, wherein at least one layer is subjected to a physical or chemical surface treatment.

[0081] Item 14. One of a container and a tray comprising the packaging material according to any one of Items 1 to 13.

[0082] Item 15. One of the containers and trays according to Item 14, wherein the packaging material is laminated to polyethylene or cross-linked polyethylene by a method selected from the group consisting of heat lamination and flame welding.

[0083] Item 16. One of the container and tray according to any one of items 14 and 15, which is thermoformed.

[0084] Item 17. A method for transporting a sharp, abrasive article, comprising placing the article in the thermoformed container of item 16.

[0085] Item 18. A method for transporting sharp, abrasive articles, comprising contacting the articles with the thermoformed tray of item 16.

[0086] Item 19. The method of any one of items 16 and 17, wherein the sharp, abrasive article is an orthopedic device.

[0087] Item 20. The method of item 19, wherein the orthopedic device is a bone implant.

[0088] Item 21. A sharp, abrasive article in a thermoformed container comprising the packaging material of any one of items 1 to 13.

[0089] Item 22. A sharp, abrasive article that comes into contact with a thermoformed tray containing the packaging material according to any one of Items 1 to 13.

Claims

1. 1. A packaging material comprising: a first layer formed from a thermoplastic polyurethane; a modified ethylene-vinyl acetate copolymer formed from a heat-activated olefinic polymer modifier containing an ethylene-vinyl acetate copolymer and a second polar comonomer; and Thermoplastic polyurethane in a proportion of 0.3% to 3.0% by weight and a second layer comprising a blend of wherein the packaging material has a total thickness of 50 μm to 600 μm, the first layer has a thickness of 20 μm to 400 μm, and the second layer has a thickness of 20 μm to 200 μm.

2. The packaging material of claim 1 , wherein the first layer comprises a thermoplastic polyurethane-ether.

3. 10. The packaging material of claim 1, wherein the first layer has a Shore hardness of 75A to 95A measured in accordance with ASTM D 2240.

4. 10. The packaging material of claim 1, wherein the ethylene-vinyl acetate copolymer contains at least 15% vinyl acetate.

5. 10. The packaging material of claim 1, wherein the olefinic polymer modifier contains less than 5000 ppm maleic anhydride.

6. 2. The packaging material of claim 1, wherein the second layer comprises a blend of a thermoplastic polyurethane and the modified ethylene-vinyl acetate copolymer in a ratio of 0.7% to 1.5% by weight.

7. 2. The packaging material of claim 1, wherein the second polar comonomer comprises one monomer selected from the group consisting of maleic anhydride, acrylic acid, acrylic acid esters, acrylic acid salts, methacrylic acid, methacrylic acid esters, and methacrylic acid salts.

8. 2. The packaging material of claim 1, wherein 0% to 30% of an additive selected from the group consisting of an antiblocking agent, an inorganic or organic spacer, a lubricating or separating aid, a pigment, a filler, and a stabilizer is added to the first layer.

9. The packaging material of claim 1 made by a coextrusion process.

10. 10. The packaging material of claim 9 made in a blown film coextrusion process.

11. 10. The packaging material of claim 1, wherein at least one layer is subjected to a physical or chemical surface treatment.

12. A container or tray comprising the packaging material of claim 1 which has been thermoformed.

13. 13. The container or tray of claim 12, wherein the packaging material is laminated to polyethylene or cross-linked polyethylene by a method selected from the group consisting of heat lamination and flame welding.

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