A high barrier light shielding gas packaging composite film

Abstract

The utility model discloses a kind of high-barrier light-shielding inflatable packaging composite films, packaging composite films, including composite film, composite film is sequentially included from outside to inside along thickness direction: outer protective layer, first adhesive layer, light-shielding layer, second adhesive layer, high-barrier composite layer, third adhesive layer, buffer layer, fourth adhesive layer and heat-sealing layer, each layer is connected by co-extrusion composite, dry method composite or solventless composite process, the high-barrier composite layer of the utility model solves the problem that single EVOH or PVDC barrier layer long-term use due to environmental humidity change causes barrier property to drop, effectively blocks oxygen and water vapor, light-shielding layer is separately arranged, avoid the problem of uneven dispersion caused by sunscreen mixing into other layers, shielding rate to ultraviolet, near-infrared can be effectively improved, better protect the product sensitive to light, the setting of buffer layer enhances the puncture resistance and rubbing resistance of composite film in inflatable state, reduce air leakage, damage problem, meet long-term storage or long-distance transportation demand.

Description

Technical Field

[0001] This utility model relates to the field of composite film technology, specifically a high-barrier, light-blocking, inflatable packaging composite film. Background Technology

[0002] In the packaging of food, pharmaceuticals, and precision electronic components, the requirements for the barrier properties (blocking oxygen and water vapor) and light-shielding properties of packaging materials are extremely high. Existing inflatable packaging composite films mostly adopt a basic three-layer structure of "substrate layer - barrier layer - heat-sealing layer", which has the following shortcomings: First, the barrier layer is mostly a single EVOH (ethylene-vinyl alcohol copolymer) or PVDC (polyvinylidene chloride), and its barrier properties are prone to decline due to changes in environmental humidity over long-term use. Second, the light-shielding layer is mostly directly mixed into the substrate layer or heat-sealing layer, with limited light-shielding effect (especially the shielding rate against ultraviolet and near-infrared rays is less than 90%), and the light-shielding agent is prone to uneven dispersion due to the processing. Third, in the inflated state, the composite film has poor puncture resistance and abrasion resistance, and is prone to air leakage and damage, which cannot meet the needs of long-term storage or long-distance transportation. Therefore, it is necessary to design a high-barrier light-shielding inflatable packaging composite film to solve the above problems. Utility Model Content

[0003] The purpose of this invention is to provide a high-barrier, light-blocking, inflatable packaging composite film to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a high-barrier light-shielding inflatable packaging composite film, comprising a composite film, wherein the composite film comprises, from the outside to the inside along the thickness direction: an outer protective layer, a first adhesive layer, a light-shielding layer, a second adhesive layer, a high-barrier composite layer, a third adhesive layer, a buffer layer, a fourth adhesive layer, and a heat-sealing layer, wherein each layer is connected by co-extrusion composite, dry composite, or solvent-free composite process, and the total thickness is 50-120μm.

[0005] Preferably, the high-barrier composite layer adopts a sandwich structure of a first EVOH layer, an aluminum foil layer, and a second EVOH layer, wherein the thickness of the first EVOH layer and the second EVOH layer is 3-8 μm, and the overall thickness of the aluminum foil layer is 6-7 μm.

[0006] Preferably, the light-shielding layer is a PET substrate with a thickness of 8-20 μm, and both sides of the PET substrate are coated with a light-shielding coating with a thickness of 1-3 μm.

[0007] Preferably, the buffer layer is a blend of LLDPE and EVA with a thickness of 10-25 μm.

[0008] Preferably, the outer protective layer has a thickness of 5-15 μm, is made of BOPP or BOPA, and has a nano-silica coating with a thickness of 0.5-1 μm on its outer surface.

[0009] Preferably, the thickness of both the first adhesive layer and the second adhesive layer is 2-5 μm, and the material is PU adhesive or EAA.

[0010] Preferably, the thickness of the third adhesive layer and the fourth adhesive layer is 2-5 μm, and the material is EAA or POE.

[0011] Preferably, the thickness of the heat-sealing layer is 20-25μm, the material is mPE, the heat-sealing temperature is 100-120℃, and the heat-sealing strength is ≥50N / 15mm.

[0012] Compared with the prior art, the beneficial effects of this utility model are: This utility model's high-barrier composite layer solves the problem of decreased barrier properties caused by changes in environmental humidity during long-term use of single EVOH or PVDC barrier layers. It effectively blocks oxygen and water vapor, extending the product's shelf life. The separate light-shielding layer avoids uneven dispersion caused by the mixing of light-shielding agents into other layers, effectively improving the shielding rate against ultraviolet and near-infrared rays, thus better protecting light-sensitive products. The buffer layer enhances the composite film's puncture resistance and abrasion resistance in the inflated state, reducing air leakage and damage, and meeting the needs of long-term storage or long-distance transportation.

[0013] This invention features a double EVOH layer and aluminum foil forming a multi-layer system that effectively blocks oxygen and water vapor, preventing product oxidation, deterioration, and moisture absorption. The aluminum foil also shields most light, reducing the adverse effects of light on the product. The sandwich structure allows each layer to work synergistically, combining flexibility and rigidity to prevent breakage and delamination, thus adapting to various packaging needs. The reasonable thickness design of each layer ensures performance while controlling costs, and facilitates processing and use.

[0014] This invention features a PET substrate light-shielding layer with light-shielding coatings on both sides, significantly improving the shielding rate against ultraviolet and near-infrared rays, effectively protecting light-sensitive products. The buffer layer, a blend of LLDPE and EVA, enhances the composite film's puncture and abrasion resistance, reducing the risk of air leakage and damage during transportation and storage. The outer protective layer, made of BOPP or BOPA material with a nano-silica coating, improves wear resistance, scratch resistance, and moisture resistance, extending the packaging's lifespan. Different adhesives are selected for different bonding layers to ensure tight bonding between layers, preventing interlayer separation and guaranteeing stable composite film quality. The heat-sealing layer, made of mPE material, achieves good heat sealing at specific temperatures with high heat-sealing strength, ensuring packaging airtightness and meeting the long-term storage requirements of products. Attached Figure Description

[0015] Figure 1This is a cross-sectional view of the overall structure of this utility model; Figure 2 This utility model Figure 1 Enlarged view of point A; Figure 3 This is a schematic diagram of the overall structure of this utility model.

[0016] In the diagram: 1. Outer protective layer; 2. First adhesive layer; 3. Light-shielding layer; 4. Second adhesive layer; 5. High-barrier composite layer; 51. First EVOH layer; 52. Aluminum foil layer; 53. Second EVOH layer; 6. Third adhesive layer; 7. Buffer layer; 8. Fourth adhesive layer; 9. Heat-sealing layer. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Example 1 Please refer to Figure 1-3 As shown, this utility model provides a high-barrier light-shielding inflatable packaging composite film, which includes a composite film. The composite film includes, from the outside to the inside along the thickness direction: an outer protective layer 1, a first adhesive layer 2, a light-shielding layer 3, a second adhesive layer 4, a high-barrier composite layer 5, a third adhesive layer 6, a buffer layer 7, a fourth adhesive layer 8, and a heat-sealing layer 9. The layers are connected by co-extrusion, dry lamination, or solvent-free lamination processes, and the total thickness is 50-120μm.

[0019] Outer protective layer 1: As the outermost layer of the composite membrane, it resists external physical damage, such as scratches and abrasions, and provides basic protection for the internal layers.

[0020] First adhesive layer 2: firmly bonds the outer protective layer 1 and the light-shielding layer 3 together, ensuring tight bonding between the layers.

[0021] Light-shielding layer 3: Specially designed to effectively block ultraviolet and near-infrared rays through its own properties, reducing the damage of light to the products inside the packaging.

[0022] Second adhesive layer 4: connects the light-shielding layer 3 and the high-barrier composite layer 5 to ensure stable bonding between layers.

[0023] High-barrier composite layer 5: It adopts a special material combination to overcome the shortcomings of single material barrier properties that are easily affected by environmental humidity, effectively blocking oxygen and water vapor, and preventing external gases from entering the packaging and affecting product quality.

[0024] The third adhesive layer 6: tightly connects the high-barrier composite layer 5 to the buffer layer 7.

[0025] Buffer layer 7: When the composite membrane is punctured or rubbed by external force in the inflated state, it absorbs energy through its own elastic deformation, reduces damage to the internal structure, and enhances puncture resistance and rubbing resistance.

[0026] Fourth adhesive layer 8: connects buffer layer 7 and heat-sealing layer 9 to ensure the integrity of the overall structure.

[0027] Heat seal layer 9: During the packaging process, the heat seal layer is melted and bonded by heating to achieve a sealed package.

[0028] The high-barrier composite layer 5 solves the problem of decreased barrier properties caused by changes in environmental humidity during long-term use of a single EVOH or PVDC barrier layer. It effectively blocks oxygen and water vapor, extending the product's shelf life. The separately set light-shielding layer 3 avoids the problem of uneven dispersion caused by the mixing of light-shielding agents into other layers. The shielding rate against ultraviolet and near-infrared rays can be effectively improved, potentially exceeding 90%, providing better protection for light-sensitive products. The buffer layer 7 enhances the composite film's puncture resistance and abrasion resistance in the inflated state, reducing air leakage and damage, and meeting the needs of long-term storage or long-distance transportation.

[0029] Specifically, the high-barrier composite layer 5 adopts a sandwich structure of a first EVOH layer 51, an aluminum foil layer 52, and a second EVOH layer 53, wherein the thickness of the first EVOH layer 51 and the second EVOH layer 53 is 3-8 μm, and the overall thickness of the aluminum foil layer 52 is 6-7 μm.

[0030] The core of aluminum foil layer 52 is to provide light shielding and basic barrier. The outer EVOH layer initially blocks external moisture and oxygen, the middle aluminum foil layer 52 blocks most gases and light, and the inner EVOH layer intercepts trace amounts of penetrating small molecules and protects the aluminum layer from corrosion by contents such as acidic substances. It can reduce the oxygen and water vapor permeability to 1 / 5 to 1 / 10 of that of a single aluminum foil layer 52, meeting the requirements of ultra-long shelf life and zero pollution.

[0031] In the field of precision packaging, such as pharmaceuticals and electronics, the barrier properties of a single aluminum foil layer 52 are insufficient. The oxygen barrier rate of EVOH is more than 1,000 times that of PE. When combined with aluminum foil layer 52, the two complement each other through their properties. Aluminum foil layer 52 ensures light shielding and mechanical strength, while EVOH achieves ultimate barrier properties, meeting the multi-functional needs of high-grade packaging.

[0032] The double EVOH layer and aluminum foil form a multi-layer system that effectively blocks oxygen and water vapor, preventing product oxidation, deterioration, and moisture absorption. The aluminum foil shields most of the light, reducing the adverse effects of light on the product. The sandwich structure allows each layer to work together, combining flexibility and rigidity, making it less prone to breakage and delamination, and adapting to various packaging needs. The reasonable thickness design of each layer ensures performance while controlling costs, and facilitates processing and use.

[0033] The light-shielding layer 3 is a PET substrate with a thickness of 8-20μm, and both sides of the PET substrate are coated with a light-shielding coating with a thickness of 1-3μm. The buffer layer 7 is a blend of LLDPE and EVA with a thickness of 10-25μm. The outer protective layer 1 has a thickness of 5-15μm and is made of BOPP or BOPA. The outer surface of the outer protective layer 1 is coated with a nano-silica coating with a thickness of 0.5-1μm. The first adhesive layer 2 and the second adhesive layer 4 are both 2-5μm thick and are made of PU adhesive or EAA. The third adhesive layer 6 and the fourth adhesive layer 8 are both 2-5μm thick and are made of EAA or POE. The heat-sealing layer 9 has a thickness of 20-25μm and is made of mPE. The heat-sealing temperature is 100-120℃ and the heat-sealing strength is ≥50N / 15mm.

[0034] Light-shielding layer 3: The PET substrate provides basic support, and the light-shielding coating on both sides absorbs or reflects light to prevent ultraviolet, near-infrared and other light rays from penetrating and protecting the products inside the packaging from light damage.

[0035] Buffer layer 7: The LLDPE and EVA blend has good elasticity and flexibility. When the composite film is punctured or rubbed by external force, this layer absorbs energy through deformation, reducing damage to the internal structure.

[0036] Outer protective layer 1: BOPP or BOPA material has a certain strength and wear resistance, protecting the internal layers; the outer surface nano silica coating enhances surface hardness, wear resistance and scratch resistance, and also improves moisture resistance.

[0037] The adhesive layers consist of a first adhesive layer 2, a second adhesive layer 4, a third adhesive layer 6, and a fourth adhesive layer 8. Adhesives of different materials are used to tightly bond adjacent layers, ensuring the stability and integrity of the overall structure of the composite film.

[0038] Heat-sealing layer 9: mPE material melts at a heat-sealing temperature of 100-120℃ and forms a strong seal after cooling, ensuring the airtightness of the packaging. The heat-sealing strength is ≥50N / 15mm to prevent air leakage.

[0039] The PET substrate of the light-shielding layer, combined with light-shielding coatings on both sides, significantly improves the shielding rate against ultraviolet and near-infrared rays, effectively protecting light-sensitive products. The buffer layer, a blend of LLDPE and EVA, enhances the composite film's puncture resistance and abrasion resistance, reducing the risk of air leakage and damage during transportation and storage. The outer protective layer, made of BOPP or BOPA material with a nano-silica coating, improves abrasion resistance, scratch resistance, and moisture resistance, extending the packaging's lifespan. Different adhesives are selected for different bonding layers to ensure a tight bond between layers, preventing interlayer separation and guaranteeing stable composite film quality. The mPE material of the heat-sealing layer achieves good heat sealing at specific temperatures and has high heat-sealing strength, ensuring packaging airtightness and meeting the long-term storage requirements of products.

[0040] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0041] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-barrier, light-blocking, inflatable packaging composite film, comprising a composite film, characterized in that: The composite film comprises, from the outside to the inside along the thickness direction, an outer protective layer (1), a first adhesive layer (2), a light-shielding layer (3), a second adhesive layer (4), a high-barrier composite layer (5), a third adhesive layer (6), a buffer layer (7), a fourth adhesive layer (8), and a heat-sealing layer (9). Each layer is connected by co-extrusion, dry lamination, or solvent-free lamination processes, with a total thickness of 50-120 μm.

2. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The high-barrier composite layer (5) adopts a sandwich structure of a first EVOH layer (51), an aluminum foil layer (52), and a second EVOH layer (53), wherein the thickness of the first EVOH layer (51) and the second EVOH layer (53) is 3-8 μm, and the overall thickness of the aluminum foil layer (52) is 6-7 μm.

3. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The light-shielding layer (3) is a PET substrate with a thickness of 8-20μm, and both sides of the PET substrate are coated with a light-shielding coating with a thickness of 1-3μm.

4. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The buffer layer (7) is a blend of LLDPE and EVA with a thickness of 10-25 μm.

5. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The outer protective layer (1) has a thickness of 5-15μm and is made of BOPP or BOPA. The outer surface of the outer protective layer (1) is provided with a nano-silica coating with a thickness of 0.5-1μm.

6. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The thickness of the first adhesive layer (2) and the second adhesive layer (4) is 2-5 μm, and the material is PU adhesive or EAA.

7. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The thickness of the third adhesive layer (6) and the fourth adhesive layer (8) is 2-5 μm, and the material is EAA or POE.

8. The high-barrier, light-blocking, inflatable packaging composite film according to claim 1, characterized in that: The thickness of the heat-sealing layer (9) is 20-25μm, the material is mPE, the heat-sealing temperature is 100-120℃, and the heat-sealing strength is ≥50N / 15mm.

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