Composite packaging material as well as preparation method and application thereof

Abstract

The invention relates to a composite packaging material as well as a preparation method and application thereof. The composite packaging material comprises a printing layer, a barrier layer, a supporting layer and a heat sealing layer which are sequentially arranged, the heat sealing layer comprises a corona layer, a core layer and an inner layer which are arranged in sequence; the corona layer comprises low-density polyethylene and linear low-density polyethylene; the core layer comprises low-density polyethylene and high-density polyethylene; the inner layer comprises low-density polyethylene, a styrene butadiene hydrogenated block copolymer and a compatilizer. The composite packaging material provided by the invention has relatively high stiffness, peeling strength of each layer, complete heat sealing strength and low oxygen and water vapor permeation amount, and can meet the characteristics of high barrier, low precipitation, complete sealing, easiness in uncovering and smooth interface.

Description

Technical Field

[0001] This invention relates to the field of plastic packaging technology, and in particular to a composite packaging material, its preparation method, and its application. Background Technology

[0002] Orally dissolving films are a novel drug delivery system characterized by their ability to dissolve spontaneously within seconds when placed on the tongue or in the mouth, eliminating the need for swallowing with water. They are widely used in pharmaceuticals, health supplements, and tobacco and e-cigarette alternatives. The packaging materials for orally dissolving films require multi-layered composite materials to achieve high barrier properties, low leaching, complete sealing, and easy opening.

[0003] Patent CN120552444A discloses a composite film for oral soluble packaging and its preparation method. It employs a three-layer composite structure: the surface layer is a stretched polyolefin (BOPP / MDOPE / MOPE); the barrier layer is an aluminized BOPP film coated with EVOH / PVDC or containing EVOH / PVDC; the heat-sealing layer consists of at least two of PE / PB / EVA, with the addition of 1-5% calcium oxide / calcium carbonate desiccant. The preparation method includes melt stretching, aluminized barrier treatment, and multi-layer composite curing process, exhibiting excellent oxygen barrier and moisture-proof properties, suitable for packaging highly humidity-sensitive products such as oral soluble films.

[0004] As is well known, adjusting the strength of the easy-open layer through PB can easily lead to an unsightly easy-open interface and problems such as stringing. Furthermore, the environmentally friendly material provided in this patent is prone to mismatch between the machine and the actual packaging machine, resulting in defects such as wrinkles and warping. Therefore, to overcome the shortcomings of the existing technology, it is necessary to provide a packaging material with high barrier properties, high stiffness, and a smooth easy-open appearance. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a composite packaging material, its preparation method, and its applications. The composite packaging material provided by this invention possesses high stiffness, heat-sealing strength, and peel strength between layers, with low oxygen and water vapor permeability, meeting the requirements of high barrier properties, low leaching, complete sealing, easy opening, and smooth interfaces.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a composite packaging material, the composite packaging material comprising a printed layer, a barrier layer, a support layer and a heat-sealing layer arranged sequentially thereon; the heat-sealing layer comprising a corona layer, a core layer and an inner layer arranged sequentially thereon.

[0008] The corona layer comprises linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE).

[0009] The core layer comprises low-density polyethylene (LDPE) and high-density polyethylene (HDPE).

[0010] The inner layer comprises low-density polyethylene (LDPE), styrene-butadiene hydrogenated block copolymer (SEBS), and a compatibilizer.

[0011] In this invention, a three-layer composite corona layer, core layer, and inner layer are used as the heat-sealing layer. The corona layer and the support layer are connected. In the corona layer, LLDPE and LDPE are compounded, which gives it high peel strength with the support layer. In the core layer, LDPE and HDPE are compounded, which provides high stiffness. In the inner layer, LDPE and SEBS are compounded to produce controllable heat-sealing strength. The resulting heat-sealing layer is connected to the printing layer, barrier layer, and support layer in sequence, which can effectively improve the stiffness, peel strength of each layer, and complete heat-sealing strength of the composite packaging material. At the same time, the oxygen and water vapor permeability is low, which can meet the characteristics of high barrier, low exudation, complete sealing and easy opening.

[0012] Preferably, the corona layer comprises 82-89 parts by weight of linear low-density polyethylene (e.g., 82, 84, 86, 88, 89, etc.) and 10-15 parts by weight of low-density polyethylene (e.g., 10, 11, 12, 13, 15, etc.).

[0013] Preferably, the core layer comprises 70-80 parts by weight of low-density polyethylene (e.g., 70, 72, 75, 78, 80, etc.) and 20-30 parts by weight of high-density polyethylene (e.g., 20, 22, 25, 28, 30, etc.).

[0014] Preferably, the inner layer comprises, by weight, 55-72 parts of low-density polyethylene (e.g., 55, 60, 65, 70, 72, etc.), 22-40 parts of styrene-butadiene hydrogenated block copolymer (e.g., 22, 25, 30, 35, 40, etc.), and 1-5 parts of compatibilizer (e.g., 1, 2, 3, 4, 5, etc.).

[0015] Preferably, the linear low-density polyethylene has a melt index of 1-4 g / 10 min at 2.16 kg and 190 °C (e.g., 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, etc.).

[0016] Preferably, the linear low-density polyethylene has a density of 0.92-0.94 g / cm³. 3 (For example, it could be 0.92 g / cm³) 3 0.925g / cm 3 0.93g / cm 30.935g / cm 3 0.94g / cm 3 wait).

[0017] Preferably, the melt index of the low-density polyethylene at 2.16 kg and 190 °C is independently 0.3-4 g / 10 min (e.g., 0.3 g / 10 min, 0.5 g / 10 min, 0.8 g / 10 min, 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, etc.).

[0018] Preferably, the density of each low-density polyethylene is independently 0.92-0.94 g / cm³. 3 (For example, it could be 0.92 g / cm³) 3 0.925g / cm 3 0.93g / cm 3 0.935g / cm 3 0.94g / cm 3 wait).

[0019] Preferably, the melt index of the high-density polyethylene at 2.16 kg and 190 °C is 0.5-4 g / 10 min (e.g., 0.5 g / 10 min, 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, etc.).

[0020] Preferably, the density of the high-density polyethylene is 0.94-0.97 g / cm³. 3 (For example, it could be 0.94 g / cm³) 3 0.95g / cm 3 0.96g / cm 3 0.97g / cm 3 wait).

[0021] Preferably, the mass content of polystyrene in the styrene-butadiene hydrogenated block copolymer is 10-30% (e.g., 10%, 15%, 20%, 25%, 30%, etc.).

[0022] Preferably, the melt index of the styrene-butadiene hydrogenated block copolymer at 2.16 kg and 230 °C is 2-10 g / 10 min (e.g., 2 g / 10 min, 4 g / 10 min, 6 g / 10 min, 8 g / 10 min, 10 g / 10 min, etc.).

[0023] Preferably, the density of the styrene-butadiene hydrogenated block copolymer is 0.90-0.94 g / cm³. 3 (For example, it could be 0.90 g / cm³) 30.91g / cm 3 0.92g / cm 3 0.93g / cm 3 0.94g / cm 3 wait).

[0024] Preferably, the compatibilizer comprises maleic anhydride-grafted polyethylene.

[0025] Preferably, the melt index of the maleic anhydride-grafted polyethylene at 2.16 kg and 190 °C is 2-4 g / 10 min (e.g., 2 g / 10 min, 2.5 g / 10 min, 3 g / 10 min, 3.5 g / 10 min, 4 g / 10 min, etc.).

[0026] Preferably, the density of the maleic anhydride-grafted polyethylene is 0.92-0.94 g / cm³. 3 (For example, it could be 0.92 g / cm³) 3 0.925g / cm 3 0.93g / cm 3 0.935g / cm 3 0.94g / cm 3 wait).

[0027] Preferably, the corona layer further includes a fluorine-free processing aid.

[0028] Preferably, the corona layer further includes 1-3 parts by weight of a fluorine-free processing aid (e.g., 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc.).

[0029] Preferably, the inner layer further includes an opening agent and / or a fluorine-free processing aid.

[0030] Preferably, the inner layer further includes 1-2 parts by weight of an opening agent (e.g., 1 part, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts, etc.) and / or 1-3 parts by weight of a fluorine-free processing aid (e.g., 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc.).

[0031] Preferably, both the printed layer and the support layer comprise polyethylene terephthalate.

[0032] Preferably, the barrier layer comprises aluminum.

[0033] Preferably, the thickness of the printed layer is 12-23 μm (e.g., it can be 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 23 μm, etc.).

[0034] Preferably, the thickness of the barrier layer is 7-9 μm (e.g., it can be 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, etc.).

[0035] Preferably, the thickness of the support layer is 23-50 μm (e.g., it can be 23 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, etc.).

[0036] Preferably, the thickness of the heat-sealing layer is 50-70 μm (e.g., it can be 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, etc.).

[0037] Preferably, the thickness of the corona layer, core layer and inner layer in the heat-sealing layer is 1:(2-4):(0.8-1.2) (for example, it can be 1:2:0.8, 1:3:0.8, 1:4:0.8, 1:2:1.2, 1:4:1.2, etc.).

[0038] In a second aspect, the present invention provides a method for preparing a composite packaging material according to the first aspect, wherein the materials of the corona layer, the core layer and the inner layer are melt-extruded and granulated respectively, and then subjected to three-layer co-extrusion and corona treatment to obtain a heat-sealing layer; the printing layer, the barrier layer, the support layer and the heat-sealing layer are sequentially bonded and cured to obtain the composite packaging material.

[0039] Thirdly, the present invention provides an application of the composite packaging material according to the first aspect in oral dissolving film packaging.

[0040] Compared with the prior art, the present invention has at least the following beneficial effects:

[0041] The composite packaging material provided by this invention includes a printed layer, a barrier layer, a support layer, and a heat-sealing layer arranged in sequence. The heat-sealing layer includes a corona layer, a core layer, and an inner layer arranged in sequence. By setting a heat-sealing layer with specific components, the resulting composite packaging material has high stiffness, peel strength of each layer, and complete heat-sealing strength. At the same time, it has low oxygen and water vapor permeability, which can meet the characteristics of high barrier, low exudation, complete sealing, easy opening, and smooth interface, and can be used for oral dissolving film packaging. Detailed Implementation

[0042] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0043] The materials used in the following embodiments are as follows:

[0044] LLDPE: Melt index 2 g / 10 min (2.16 kg, 190℃), density 0.92 g / cm³ 3The manufacturer's brand name is Shanghai SECCO LD 0220AA;

[0045] LDPE: Melt index 0.75 g / 10 min (2.16 kg, 190℃), density 0.92 g / cm³ 3 The manufacturer's brand name is CNOOC Shell 2420D;

[0046] HDPE: Melt index 1 g / 10 min (2.16 kg, 190℃), density 0.94 g / cm³ 3 The manufacturer's brand name is Dow Chemical AT 6900;

[0047] SEBS: Polystyrene content 13%, melt index 4 g / 10 min (2.16 kg, 230℃), density 0.92 g / cm³ 3 The manufacturer's brand name is KETEN G 1645;

[0048] PE-g-MAH: Melt index 3 g / 10 min (2.16 kg, 190℃), density 0.92 g / cm³ 3 The manufacturer's brand name is Dow Chemical Bynel 4157;

[0049] Fluorine-free processing aid: Manufacturer's brand name is Kinzu 7M8017;

[0050] Opening agent: Manufacturer's brand name is Mitsui EAZ-10.

[0051] Example 1

[0052] This embodiment provides a composite packaging material, comprising a printed layer, a barrier layer, a support layer, and a heat-sealing layer arranged sequentially.

[0053] The printing layer is a 12μm PET film (Sanfangxiang), the barrier layer is a 7μm aluminum film, the support layer is a 50μm PET film (Yongsheng), and the heat-sealing layer is 50μm. It includes a corona layer, a core layer, and an inner layer arranged sequentially with a thickness ratio of 1:3:1. The composition is shown below:

[0054]

[0055] The method for preparing the composite packaging material includes the following steps:

[0056] The materials of the corona layer, core layer, and inner layer are melt-extruded and granulated at 180°C, 190°C, and 200°C respectively using a twin-screw extruder. Then, they are melted at 200°C in a co-extrusion blown film equipment. After three-layer co-extrusion, cooling and shaping, and corona treatment, a heat-sealing layer is obtained. The printing layer, barrier layer, support layer, and heat-sealing layer are bonded sequentially with polyurethane adhesive, cured at 45°C, cooled, and slit to obtain the composite packaging material.

[0057] Example 2

[0058] This embodiment provides a composite packaging material, comprising a printed layer, a barrier layer, a support layer, and a heat-sealing layer arranged sequentially.

[0059] The printing layer is a 23μm PET film (Yongsheng), the barrier layer is a 9μm aluminum film, the support layer is a 23μm PET film (Yongsheng), and the heat-sealing layer is 60μm. It includes a corona layer, a core layer, and an inner layer arranged sequentially with a thickness ratio of 1:4:1. The composition is shown below:

[0060]

[0061] The preparation method is the same as in Example 1.

[0062] Example 3

[0063] This embodiment provides a composite packaging material, comprising a printed layer, a barrier layer, a support layer, and a heat-sealing layer arranged sequentially.

[0064] The printing layer is a 23μm PET film (manufacturer's brand), the barrier layer is a 9μm aluminum film, the support layer is a 50μm PET film (manufacturer's brand), and the heat-sealing layer is 70μm. It includes a corona layer, a core layer, and an inner layer arranged sequentially with a thickness ratio of 1:3:1. The composition is shown below:

[0065]

[0066] The preparation method is the same as in Example 1.

[0067] Example 4

[0068] This embodiment provides a composite packaging material, which differs from Embodiment 1 only in that the corona layer contains 85 parts LDPE and 12 parts LLDPE, while other aspects are the same as in Embodiment 1.

[0069] Comparative Example 1

[0070] This embodiment provides a composite packaging material, which differs from Embodiment 1 only in that the core layer is entirely LDPE and contains no HDPE; otherwise, it is the same as Embodiment 1.

[0071] Comparative Example 2

[0072] This comparative example provides a composite packaging material that differs from Example 1 only in that the inner layer does not contain SEBS, and its amount is allocated to LDPE; otherwise, it is the same as in Example 1.

[0073] Comparative Example 3

[0074] This comparative example provides a composite packaging material, which differs from Example 1 only in that the inner layer does not contain PE-g-MAH, and its amount is allocated to LDPE. Other aspects are the same as in Example 1.

[0075] The composite packaging materials of Examples 1-4 and Comparative Examples 1-3 were subjected to performance tests according to the following standards:

[0076] (1) Heat seal strength: The heat seal strength shall be tested in accordance with the test method provided in QB / T 2358-1998;

[0077] (2) Peel strength: The interlayer peel strength shall be tested in accordance with the provisions of GB / T 8808-1988;

[0078] (3) Oxygen permeability: The conditions are 0.1 MPa, 23℃, 0%RH, and the oxygen permeability is tested according to the test method provided in GB / T 19789-2005;

[0079] (4) Water vapor transmission rate: The conditions are 38℃ and 90%RH. The water vapor transmission rate is tested according to the test method provided in GB / T 26253-2010.

[0080] (5) Stiffness: Tested in accordance with GB / T 22364-2018.

[0081] Examples 1-4 and Comparative Examples 1-3 were tested according to the above method, and the results are shown in Table 1.

[0082] Table 1

[0083]

[0084] in conclusion:

[0085] As can be seen from Examples 1-4 in Table 1, the composite packaging material provided by the present invention has an easy-to-open heat-seal strength (3-6 N / 15 mm) and a peel strength of each layer (≥1.8 N / 15 mm), and low oxygen permeability (<0.1 cm). 3 / m 2 • 24h), low water vapor permeability (<0.1g / m³) 2 • 24h), PE film has high stiffness (50-60mN), which can meet the characteristics of high barrier, low exudation, complete sealing and easy peeling with smooth interface.

[0086] A comparison of Examples 1 and 4 shows that when the LDPE content in the corona layer is too high, the peel strength of the support layer and the heat seal layer is low, below 2N / 15mm.

[0087] By comparing Example 1 and Comparative Example 1, it can be seen that when the core layer in the heat-sealing layer does not contain HDPE, the stiffness of the heat-sealing PE layer is relatively small.

[0088] A comparison of Example 1 and Comparative Examples 2-3 shows that SEBS and PE-g-MAH in the inner layer have a synergistic effect. When SEBS is lacking, the heat-sealing strength is high, but the easy-peeling effect is not achieved. When PE-g-MAH is lacking, the compatibility between LDPE and SEBS is poor, and the easy-peeling appearance is not smooth and does not meet customer needs.

[0089] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A composite packaging material, characterized in that, The composite packaging material comprises a printing layer, a barrier layer, a support layer and a heat-sealing layer arranged in sequence; the heat-sealing layer comprises a corona layer, a core layer and an inner layer arranged in sequence; The corona layer comprises linear low-density polyethylene and low-density polyethylene; The core layer comprises low-density polyethylene and high-density polyethylene; The inner layer comprises low-density polyethylene, styrene butadiene hydrogenated block copolymer and a compatibilizer.

2. The composite packaging material according to claim 1, characterized in that, The corona layer comprises linear low-density polyethylene 82-89 parts by mass and low-density polyethylene 10-15 parts by mass; Preferably, the core layer comprises low-density polyethylene 70-80 parts by mass and high-density polyethylene 20-30 parts by mass; Preferably, the inner layer comprises low-density polyethylene 55-72 parts by mass, styrene butadiene hydrogenated block copolymer 22-40 parts by mass and a compatibilizer 1-5 parts by mass.

3. The composite packaging material according to claim 1 or 2, characterized in that, The linear low-density polyethylene has a melt index of 1-4 g / 10 min at 2.16 kg and 190℃, respectively and independently; Preferably, the linear low density polyethylenes have a density independently of each other of 0.92 to 0.94 g / cm3 3 ; preferably, the low density polyethylenes have a melt index at 2.16 kg, 190°C of 0.3 to 4 g / 10 min; Preferably, the low density polyethylene has a density of 0.92 to 0.94 g / cm3 3 .

4. The composite packaging material according to any one of claims 1-3, characterized in that, The high-density polyethylene has a melt index of 0.5-4 g / 10 min at 2.16 kg and 190℃; Preferably, the high density polyethylene has a density of 0.94 to 0.97 g / cm3 3 .

5. The composite packaging material according to any one of claims 1-4, characterized in that, The styrene butadiene hydrogenated block copolymer has a mass content of polystyrene of 10-30%; Preferably, the styrene butadiene hydrogenated block copolymer has a melt index of 2-10 g / 10 min at 2.16 kg and 230℃; Preferably, the styrene butadiene hydrogenated block copolymer has a density of 0.90 to 0.94 g / cm3 3 ; Preferably, the compatibilizer comprises maleic anhydride grafted polyethylene; Preferably, the maleic anhydride grafted polyethylene has a melt index of 2-4 g / 10 min at 2.16 kg and 190℃; Preferably, the density of the maleic anhydride grafted polyethylene is between 0.92 and 0.94 g / cm3 3 .

6. The composite packaging material according to any one of claims 1-5, characterized in that, The corona layer further comprises a fluorine-free processing aid; Preferably, the corona layer further comprises a fluorine-free processing aid 1-3 parts by mass; Preferably, the inner layer further comprises an opening agent and / or a fluorine-free processing aid; Preferably, the inner layer further comprises an opening agent 1-2 parts by mass and / or a fluorine-free processing aid 1-3 parts by mass.

7. The composite packaging material according to any one of claims 1-6, characterized in that, The printing layer and the support layer both comprise polyethylene terephthalate; Preferably, the barrier layer comprises aluminum.

8. The composite packaging material according to any one of claims 1-7, characterized in that, The thickness of the printing layer is 12-23 μm; Preferably, the thickness of the barrier layer is 7-9 μm; Preferably, the thickness of the support layer is 23-50 μm; Preferably, the thickness of the heat-sealing layer is 50-70 μm; Preferably, the thickness of the corona layer, the core layer and the inner layer in the heat-sealing layer is 1:(2-4):(0.8-1.2).

9. A method of producing a composite packaging material according to any one of claims 1-8, characterized in that, The materials of the corona layer, the core layer and the inner layer are respectively melt-extruded and granulated, then co-extruded in three layers and treated by corona to obtain the heat-sealing layer; the printing layer, the barrier layer, the support layer and the heat-sealing layer are bonded in sequence and subjected to curing treatment to obtain the composite packaging material.

10. Use of the composite packaging material according to any one of claims 1-8 in oral dissolving film packaging.

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