Fold-resistant packaging material

Abstract

The application provides a folding-resistant packaging material, and relates to the field of packaging materials. The folding-resistant packaging material comprises, from bottom to top, a breathable control layer, a breathable support layer, a buffer layer and a leakage prevention layer. The breathable control layer is used to contact a product to be packaged. The buffer layer and the leakage prevention layer are provided with an array of rib-like structures that are compressed along the thickness direction of the packaging material. The strength of the breathable support layer is greater than that of the breathable control layer. The folding-resistant packaging material has good breathability and folding resistance.

Description

Technical Field

[0001] This application relates to the field of packaging technology, and more specifically, to a foldable packaging material. Background Technology

[0002] Desiccants are substances that can adsorb or absorb water vapor from the surrounding environment. Their core function is to reduce humidity in enclosed or semi-enclosed spaces, thereby preventing items from deteriorating, corroding, clumping, or becoming moldy due to moisture. Since desiccants are generally used for a long time and may be transported over long distances, the packaging material for desiccants needs to have good air permeability and moisture absorption, as well as a certain degree of strength and folding resistance.

[0003] Currently, traditional nonwoven fabric materials have good air permeability but poor folding resistance. After 100 bends, the air permeability decreases by more than 30%, and microcracks are easily generated, leading to desiccant leakage. Although conventional PTFE (polytetrafluoroethylene) membranes are waterproof and breathable, they are prone to permanent deformation after repeated folding, resulting in a decrease in porosity. Some composite film materials, such as PE (polyethylene) and PP (polypropylene) composites, have a certain degree of flexibility, but they have a high risk of delamination after long-term folding. Utility Model Content

[0004] The purpose of this application is to provide a foldable packaging material to improve the technical problem that current packaging materials cannot simultaneously achieve good breathability and foldability.

[0005] In a first aspect, embodiments of this application provide a foldable packaging material, including a breathable control layer, a breathable support layer, a buffer layer and a leak-proof layer arranged sequentially from bottom to top. The breathable control layer is used to contact the product to be packaged. The buffer layer and the leak-proof layer have arrayed rib structures pressed along the thickness direction of the packaging material. The strength of the breathable support layer is greater than the strength of the breathable control layer.

[0006] In the above implementation process, this application arranges the breathable control layer, breathable support layer, buffer layer and leak-proof layer in sequence from bottom to top to form a composite packaging material. The breathable control layer and breathable support layer have good breathability, while the buffer layer and leak-proof layer have an array of rib-like structures pressed along the thickness direction of the packaging material, which improves the resilience of the buffer layer and leak-proof layer to have good folding resistance. In other areas where no rib-like structures are formed, the porosity is high to maintain good breathability. In addition, it has a certain strength, so that the composite packaging material has both good breathability and folding resistance.

[0007] In one possible implementation, the rib-like structure is dot-like, and the dot-like rib-like structures are distributed in an array; or the rib-like structure is linear, and the linear rib-like structures are distributed in an array.

[0008] This application uses an array of dot-shaped or linear rib-like structures to improve the resilience of the buffer layer and the leak-proof layer, thereby enhancing their folding resistance.

[0009] In one possible implementation, the rib structure is linear, and the linear rib structures are distributed in an array along the plane of the foldable packaging material, with each row of linear rib structures forming an alternating V-shaped structure.

[0010] The linear rib-like structures in this application are arranged in an array, wherein each row of linear rib-like structures forms an alternating V-shaped structure, which helps to further improve the folding resistance of the buffer layer and the leak-proof layer, and further improves its strength.

[0011] In one possible implementation, the rib structure is a composite structure of point and line structures. The point rib structures are distributed in an array, and the line rib structures are distributed in an array, with a row of line rib structures placed between two adjacent rows of point rib structures.

[0012] This application uses a composite arrangement of dot-like and linear rib-like structures in an array pattern, which helps to further enhance the folding resistance and strength of the buffer layer and the leak-proof layer.

[0013] In one possible implementation, the ratio of the sum of the thicknesses of the buffer layer and the leak-proof layer to the thickness of the breathable support layer is (3~10):1.

[0014] This application sets the sum of the thicknesses of the buffer layer and the leak-proof layer to a suitable ratio with the thickness of the breathable support layer. This allows the buffer layer and the leak-proof layer to have good folding resistance while maintaining good breathability. At the same time, the breathable support layer has a certain mechanical strength and good breathability, so that the composite packaging material has a balance between a certain mechanical strength and good folding resistance and breathability.

[0015] In one possible implementation, the sum of the thicknesses of the cushioning layer and the leak-proof layer is 65% to 85% of the total thickness of the foldable packaging material.

[0016] This application sets the sum of the thicknesses of the buffer layer and the leak-proof layer to a suitable ratio with the total thickness of the packaging material. This allows the buffer layer and the leak-proof layer to have good folding resistance while maintaining good breathability and a certain strength. As a result, the composite packaging material has both good folding resistance and breathability, as well as a certain degree of impact resistance.

[0017] In one possible implementation, the combined thickness of the buffer layer and the leak-proof layer is 50~400 μm, and the mass per unit area is 30~100 g / m².

[0018] This application uses a buffer layer and a leak-proof layer with appropriate total thickness and appropriate unit area mass, so that the packaging material formed by combining with the breathability control layer and the breathability support layer has good breathability, good folding resistance and a certain impact resistance, while balancing an appropriate cost.

[0019] In one possible implementation, the total thickness of the foldable packaging material is 70~500 μm.

[0020] This application employs a packaging material formed by combining a breathable control layer, a breathable support layer, a buffer layer, and a leak-proof layer, with a suitable total thickness, so that the composite packaging material has good breathability, folding resistance, impact resistance, mechanical strength, and leak-proof properties, while balancing a suitable weight and cost.

[0021] In one possible implementation, the thickness of the buffer layer is 40~300 μm, and the thickness of the leak-proof layer is 10~100 μm.

[0022] This application uses a buffer layer and a leak-proof layer of appropriate thickness to meet certain leak-proof requirements and a certain strength. At the same time, they are easy to combine to form an appropriate thickness, so as to give full play to their advantages of good folding resistance and maintain good breathability. Thus, the packaging material formed by combining with the breathability control layer and the breathability support layer can meet certain puncture resistance and reduce leakage of the packaged product, while also having good breathability and folding resistance.

[0023] In one possible implementation, the thickness of the breathable control layer is 10~100 μm, and the thickness of the breathable support layer is 10~50 μm.

[0024] This application employs a breathable control layer of appropriate thickness to leverage its excellent breathability; simultaneously, it employs a breathable support layer of appropriate thickness to maintain good breathability while also possessing a certain degree of mechanical strength. Thus, the packaging material formed by combining the cushioning layer and the leak-proof layer has good folding resistance, as well as good breathability and a certain degree of mechanical strength.

[0025] In one possible implementation, the pore density of both the breathable control layer and the breathable support layer is 10~80 pores / cm², and the average pore diameter is 0.3~1.0 mm.

[0026] Both the breathable control layer and the breathable support layer of this application adopt appropriate pore density and average pore size so that the composite packaging material has good breathability while preventing leakage.

[0027] In one possible implementation, the leak-proof layer is selected from glass fiber filter paper, plant fiber filter paper, synthetic fiber filter paper, or microporous membrane; the buffer layer is selected from spunbond nonwoven fabric, thermally rolled nonwoven fabric, or meltblown nonwoven fabric; the breathable support layer is selected from polypropylene or polyethylene terephthalate; and the breathable control layer is selected from polyethylene membrane or polypropylene membrane.

[0028] The leak-proof layer of this application uses a suitable material, which facilitates stable contact with the product to be packaged and prevents leakage. It also facilitates the formation of an array of ribs pressed along the thickness direction of the packaging material when combined with the cushioning layer. The cushioning layer uses a suitable material, which facilitates the formation of an array of ribs pressed along the thickness direction of the packaging material when combined with the leak-proof layer to reduce punctures by the product to be packaged. Simultaneously, it facilitates the formation of an array of ribs pressed along the thickness direction of the packaging material when combined with the breathability control layer and the breathability support layer. Furthermore, it facilitates the formation of a breathable material when combined with the breathability control layer and the breathability support layer, reducing stress concentration and cracking. The breathability support layer uses a suitable material, which facilitates the formation of a packaging material with a certain mechanical strength when combined with the breathability control layer, the cushioning layer, and the leak-proof layer. The breathability control layer uses a suitable material, which facilitates the formation of a packaging material with good breathability when combined with the breathability support layer, the cushioning layer, and the leak-proof layer. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a cross-sectional view of the foldable packaging material provided in an embodiment of this application.

[0031] Figure 2 This is a top view of the foldable packaging material provided in Embodiment 1 of this application.

[0032] Figure 3 This is a top view of the foldable packaging material provided in Embodiment 2 of this application.

[0033] Figure 4 This is a top view of the foldable packaging material provided in Embodiment 3 of this application.

[0034] Icons: 1-Breathable control layer; 2-Breathable support layer; 3-Buffer layer; 4-Leak-proof layer; 5-Rib-like structure. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0037] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0038] In the description of this application, it should be noted that the terms "center," "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0039] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0040] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0041] This application aims to address the technical problem that existing packaging materials cannot simultaneously achieve good breathability and folding resistance, and proposes a folding-resistant packaging material, such as... Figure 1As shown, the packaging includes a breathable control layer 1, a breathable support layer 2, a buffer layer 3, and a leak-proof layer 4 arranged sequentially from bottom to top. The breathable control layer 1 is used to contact the product to be packaged. The buffer layer 3 and the leak-proof layer 4 have an array of rib-like structures 5 pressed together along the thickness direction of the packaging material. The strength of the breathable support layer 2 is greater than the strength of the breathable control layer 1.

[0042] By sequentially arranging the breathable control layer 1, breathable support layer 2, buffer layer 3, and leak-proof layer 4 from bottom to top, a composite packaging material is formed. The breathable control layer 1 and breathable support layer 2 have good breathability, while the buffer layer 3 and leak-proof layer 4 have arrayed rib-like structures 5 pressed along the thickness direction of the packaging material, which improves the resilience of the buffer layer 3 and leak-proof layer 4 to have good folding resistance. In other areas where the rib-like structures 5 are not formed, the porosity is high to maintain good breathability. In addition, it has a certain strength, thus enabling the composite packaging material to have both good breathability and folding resistance.

[0043] In some embodiments, the rib-like structures are dot-like, and the dot-like rib-like structures are distributed in an array; or the rib-like structures are linear, and the linear rib-like structures are distributed in an array. It should be noted that the diameter of the dot-like rib-like structures is 0.4~0.8 mm, and the spacing between two adjacent dot-like rib-like structures is 5~9 mm. Distributing the dot-like or linear rib-like structures in an array helps to improve the resilience of the buffer layer and the leak-proof layer, thus providing better folding resistance.

[0044] In some embodiments, the rib-like structures are linear, and these linear rib-like structures are distributed in an array along the plane of the foldable packaging material. Each row of linear rib-like structures forms an alternating V-shaped structure. It should be noted that the length of the linear rib-like structures is 0.6~1.2 mm, and the width is 0.3~0.6 mm. The linear rib-like structures distributed in an array, with each row forming an alternating V-shaped structure, further enhance the foldability and strength of the cushioning and leak-proof layers.

[0045] In some embodiments, the rib structure is a composite structure of dot-like and linear ribs. The dot-like ribs are distributed in an array, and the linear ribs are also distributed in an array, with a row of linear ribs spaced between adjacent rows of dot-like ribs. It should be noted that the spacing between adjacent rows of dot-like ribs in a row of linear ribs is equal. This composite arrangement of dot-like and linear ribs in an array helps to synergistically enhance the folding resistance and strength of the buffer layer and the leak-proof layer.

[0046] In some embodiments, the ratio of the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 to the thickness of the breathable support layer 2 is (3~10):1. As an example, the ratio of the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 to the thickness of the breathable support layer 2 may be, but is not limited to, 3:1, 3.5:1, 3.6:1, 3.8:1, 4:1, 4.5:1, 4.6:1, 4.7:1, 5:1, 5.5:1, 5.6:1, 5.8:1, 6:1, 6.5:1, 6.8:1, 7:1, 7.5:1, 7.8:1, 8:1, 8.5:1, 8.8:1, 9:1, 9.5:1, 9.8:1, 10:1. By setting the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 to a suitable ratio with the thickness of the breathable support layer 2, the advantages of the buffer layer 3 and the leak-proof layer 4 in terms of good folding resistance are brought into play, while maintaining good breathability in a balanced manner. At the same time, the advantages of the breathable support layer 2 in terms of certain mechanical strength are brought into play, while also having good breathability. This allows the composite packaging material to balance a certain mechanical strength with good folding resistance and breathability.

[0047] In some embodiments, the sum of the thicknesses of the cushioning layer 3 and the leak-proof layer 4 represents a percentage of 65% to 85% of the total thickness of the foldable packaging material. For example, the percentage of the sum of the thicknesses of the cushioning layer 3 and the leak-proof layer 4 to the total thickness of the foldable packaging material can be, but is not limited to, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, or 85%. Further, the percentage of the sum of the thicknesses of the cushioning layer 3 and the leak-proof layer 4 to the total thickness of the foldable packaging material is 69% to 75%. By setting the sum of the thicknesses of the cushioning layer 3 and the leak-proof layer 4 to a suitable ratio with the total thickness of the packaging material, the advantages of the good foldability of the cushioning layer 3 and the leak-proof layer 4 are utilized while maintaining good breathability, and a certain degree of strength is also achieved. This results in a composite packaging material that possesses both good foldability and breathability, as well as a certain degree of impact resistance.

[0048] In some embodiments, the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 is 50-400 μm, and the unit area mass is 30-100 g / m². As an example, the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 can be, but is not limited to, 50 μm, 70 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, or 400 μm. Further, the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 is 50-300 μm. Even further, the sum of the thicknesses of the buffer layer 3 and the leak-proof layer 4 is 50-100 μm. By using a buffer layer 3 and a leak-proof layer 4 with suitable total thickness and suitable unit area mass, the packaging material formed by combining it with the breathability control layer 1 and the breathability support layer 2 has good breathability, good folding resistance, and a certain degree of impact resistance, while balancing a suitable cost.

[0049] In some embodiments, the thickness of the buffer layer 3 is 40-300 μm, and the thickness of the leak-proof layer 4 is 10-100 μm. Exemplarily, the thickness of the buffer layer 3 may be, but is not limited to, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 220 μm, 250 μm, 280 μm, or 300 μm. Further, the thickness of the buffer layer 3 is 40-100 μm. Even further, the thickness of the buffer layer 3 is 40-60 μm. Exemplarily, the thickness of the leak-proof layer 4 may be, but is not limited to, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, or 100 μm. Furthermore, the thickness of the leak-proof layer 4 is 10~80 μm. Even further, the thickness of the leak-proof layer 4 is 10~40 μm. Using a buffer layer 3 and a leak-proof layer 4 of suitable thickness can meet certain leak-proof requirements and a certain strength. At the same time, they are easily combined to form a suitable thickness, allowing them to leverage their good folding resistance while maintaining good breathability. Thus, the packaging material formed by combining the leak-proof layer 1 and the breathable support layer 2, while meeting certain puncture resistance requirements and reducing leakage of the packaged product, also possesses good breathability and folding resistance.

[0050] In some embodiments, the thickness of the breathability control layer 1 is 10-100 μm, and the thickness of the breathability support layer 2 is 10-50 μm. Exemplarily, the thickness of the breathability control layer 1 can be, but is not limited to, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, or 100 μm. Further, the thickness of the breathability control layer 1 is 10-70 μm. Even further, the thickness of the breathability control layer 1 is 10-20 μm. Exemplarily, the thickness of the breathability support layer 2 can be, but is not limited to, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm. Furthermore, the thickness of the breathable support layer 2 is 10~30 μm. Even further, the thickness of the breathable support layer 2 is 10~20 μm. By employing a breathable control layer 1 of suitable thickness, its excellent breathability is maximized; simultaneously, a breathable support layer 2 of suitable thickness is used to maintain good breathability while also possessing a certain degree of mechanical strength. Thus, the packaging material formed by combining the support layer 3 and the leak-proof layer 4 possesses good folding resistance, as well as good breathability and a certain degree of mechanical strength.

[0051] In some embodiments, the total thickness of the foldable packaging material is 70-500 μm. As an example, the total thickness of the foldable packaging material may be, but is not limited to, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 220 μm, 250 μm, 280 μm, 300 μm, 320 μm, 350 μm, 380 μm, 400 μm, 420 μm, 450 μm, 480 μm, or 500 μm. Further, the total thickness of the foldable packaging material is 70-200 μm. Even further, the total thickness of the foldable packaging material is 70-140 μm. The packaging material formed by combining the breathable control layer 1, the breathable support layer 2, the buffer layer 3, and the leak-proof layer 4 has an appropriate total thickness, so that the composite packaging material has good breathability, folding resistance, impact resistance, mechanical strength, and leak prevention, while balancing appropriate weight and cost.

[0052] In some embodiments, the pore density of both the breathable control layer 1 and the breathable support layer 2 is 10-80 pores / cm², and the average pore diameter is 0.3-1.0 mm. As an example, the pore density of both the breathable control layer 1 and the breathable support layer 2 may be, but is not limited to, 10 pores / cm², 15 pores / cm², 20 pores / cm², 25 pores / cm², 30 pores / cm², 35 pores / cm², 40 pores / cm², 45 pores / cm², 50 pores / cm², 55 pores / cm², 60 pores / cm², 65 pores / cm², 70 pores / cm², 75 pores / cm², or 80 pores / cm². Further, the pore density of both the breathable control layer 1 and the breathable support layer 2 is 25-50 pores / cm². As an example, the average pore size of both the breathability control layer 1 and the breathability support layer 2 can be, but is not limited to, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, and 1.0 mm. Further, the average pore size of both the breathability control layer 1 and the breathability support layer 2 is 0.3 to 0.8 mm. Both the breathability control layer 1 and the breathability support layer 2 employ suitable pore density and average pore size to ensure that the composite packaging material, while preventing leakage, also possesses good breathability.

[0053] In some embodiments, the leak-proof layer 4 is selected from glass fiber filter paper, plant fiber filter paper, synthetic fiber filter paper, and microporous membrane. For example, plant fiber filter paper may be, but is not limited to, wood pulp fiber filter paper or cotton pulp fiber filter paper. Synthetic fiber filter paper may be, but is not limited to, PP (polypropylene) fiber filter paper or PET (polyethylene terephthalate) fiber filter paper. Microporous membrane may be, but is not limited to, PE (polyethylene) microporous membrane or PP microporous membrane. The leak-proof layer 4 is made of a suitable material that facilitates stable contact with the product to be packaged, prevents leakage, and facilitates the formation of an array of ribbed structures 5 pressed along the thickness direction of the packaging material when combined with the buffer layer 3.

[0054] In some embodiments, the buffer layer 3 is selected from spunbond nonwoven fabric, thermally bonded nonwoven fabric, or meltblown nonwoven fabric. As an example, the spunbond nonwoven fabric can be, but is not limited to, PP spunbond nonwoven fabric or PET spunbond nonwoven fabric. The buffer layer 3 is made of a suitable material that facilitates its combination with the leak-proof layer 4 to reduce the risk of the leak-proof layer 4 being punctured by the product to be packaged, and also facilitates its combination with the leak-proof layer 4 to form an array of ribbed structures 5 pressed along the thickness direction of the packaging material; simultaneously, it facilitates its combination with the breathability control layer 1 and the breathability support layer 2 to reduce stress concentration and cracking caused by the combination of the breathability control layer 1 and the breathability support layer 2.

[0055] In some embodiments, the breathable support layer 2 is selected from polypropylene (PP) or polyethylene terephthalate (PET). The breathable support layer 2 is made of a suitable material, which helps the packaging material formed by combining it with the breathable control layer 1, the buffer layer 3 and the leak-proof layer 4 to have a certain mechanical strength.

[0056] In some embodiments, the breathability control layer 1 is selected from polyethylene film or polypropylene film. The breathability control layer 1 is made of a suitable material, which is beneficial to the packaging material formed by combining it with the breathable support layer 2, the buffer layer 3 and the leak-proof layer 4, so that it has good breathability.

[0057] It should be noted that the breathable support layer 2 and the breathable control layer 1 are made of different materials. When the breathable control layer 1 is made of polypropylene film, the breathable support layer 2 is made of polyethylene terephthalate.

[0058] A leak-proof layer 4 and a buffer layer 3 of suitable thickness are hot-rolled and then cooled to form an array of ribbed structures 5 pressed together along their thickness direction. This improves resilience and allows the layers to absorb and disperse stress when subjected to bending stress, preventing stress concentration and breakage. This results in good folding resistance, as well as some tear and puncture resistance. Simultaneously, areas without the ribbed structure 5 exhibit high porosity, which helps maintain good air permeability. A breathable support layer 2 and a breathable regulating layer 1 of suitable thickness are then added. After hot-pressing and bonding, the holes are directly punctured with cold needles to form suitable average pore size and pore density. Then, hot air or infrared instantaneous heating is used to melt and fold the edges of the holes, melting and smoothing the burrs to form smooth hole edges, thus forming low-resistance vapor channels with good air permeability. The leak-proof layer 4 and buffer layer 3, as well as the breathable support layer 2 and breathable control layer 1, are then bonded together from top to bottom using a dotted hot melt adhesive array to form a foldable packaging material that combines good air permeability and foldability.

[0059] Example 1 This embodiment provides a foldable packaging material, such as Figures 1-2As shown, the packaging includes, from bottom to top, a breathable control layer, a breathable support layer, a buffer layer, and a leak-proof layer. The thickness of the breathable control layer is 15 μm, the thickness of the breathable support layer is 15 μm, the thickness of the buffer layer is 60 μm, and the thickness of the leak-proof layer is 10 μm. The breathable control layer is used to contact the product to be packaged. The buffer layer and the leak-proof layer have an array of rib-like structures pressed together along the thickness direction of the packaging material. The rib-like structures are dot-like, with a diameter of 0.5 mm and a spacing of 8 mm between two adjacent dot-like rib-like structures. The strength of the breathable support layer is greater than that of the breathable control layer. The pore density of the breathable control layer and the breathable support layer is 30 pores / cm², and the average pore diameter is 0.5 mm. The breathable control layer is made of polyethylene film, the breathable support layer is made of polypropylene, the buffer layer is made of PP spunbond nonwoven fabric, and the leak-proof layer is made of PET fiber filter paper.

[0060] Example 2 This embodiment provides a foldable packaging material, such as Figure 3 As shown, the difference from Example 1 is that the rib structure is linear, the linear rib structure is distributed in an array, and along the plane direction of the foldable packaging material, each row of linear rib structure forms an alternating V-shaped structure; the length of the linear rib structure is 0.8 mm and the width is 0.3 mm.

[0061] Example 3 This embodiment provides a foldable packaging material, such as Figure 4 As shown, the difference from Example 1 is that the rib structure is a composite structure of dot and line structures. The dot rib structures are distributed in an array, and the line rib structures are also distributed in an array. A row of line rib structures is set between two adjacent rows of dot rib structures. The diameter of the dot rib structure is 0.5 mm, and the distance between two adjacent dot rib structures is 8 mm. The length of the line rib structure is 0.8 mm, and the width is 0.3 mm. The distance between two adjacent rows of dot rib structures in a row of line rib structures is equal.

[0062] Comparative Example 1 This comparative example provides a packaging material that differs from Example 1 in that the buffer layer and the leak-proof layer are directly laminated together, without having an array of ribbed structures pressed along the thickness direction of the packaging material.

[0063] Comparative Example 2 This comparative example provides a packaging material that differs from Example 1 in that it does not include a breathable support layer.

[0064] Experimental Example 1 This experimental example involves performance testing of the packaging materials prepared in Examples 1-3 and Comparative Examples 1-2; specifically: Folding resistance: Using the MIT folding resistance tester, the packaging sample was folded back and forth at a 135° angle under a tension of 1.0 kgf, and the number of times the packaging sample broke was recorded. Air permeability: Fix each packaging material sample on the test chamber, apply a pressure difference of 100Pa, and use a gas flow meter to detect the air permeability; Water vapor transmission rate (WVTR): The packaging sample is sealed on a permeation cup containing desiccant particles and placed in an environment of 38°C and 90% RH. After 24 hours, the sample is weighed and the water vapor transmission rate is calculated. WVTR = (m2-m1) / (A×24), where m2 is the weight of the desiccant particles after 24 hours, m1 is the initial weight of the desiccant particles, and A is the effective test area of ​​the packaging material. The results are shown in Table 1.

[0065] Table 1 Packaging Material Performance

[0066] As shown in Table 1, the foldable packaging materials provided in Examples 1-3 of this application, arranged sequentially from bottom to top, include a breathable control layer, a breathable support layer, a buffer layer, and a leak-proof layer. The buffer layer and leak-proof layer have a dotted array of ribs pressed along the thickness direction of the packaging material. The breathable control layer and the breathable support layer have suitable pore density and average pore size, with a folding resistance greater than 1000 times, an air permeability greater than 180 L / m²·s, and a water vapor transmission rate greater than 450 g / m²·24h, exhibiting good folding resistance and excellent breathability. In Comparative Example 1, the buffer layer and leak-proof layer lack the array of ribs pressed along the thickness direction of the packaging material, resulting in significantly reduced folding resistance. Comparative Example 2 does not include a breathable support layer, leading to a decrease in the overall structural strength of the packaging material and a significant reduction in folding resistance. This demonstrates that the foldable packaging materials provided in this application possess both good folding resistance and breathability.

[0067] Experimental Example 2 In this experiment, the packaging materials prepared in Examples 1-3 and Comparative Examples 1-2 were hot-pressed at 160°C to seal three sides of the PTFE microporous packaging material, forming a cavity. 10g of magnesium chloride granules were then filled into the cavity, and the cavity was sealed again at 160°C to form a desiccant. The performance of the desiccants prepared from the packaging materials provided in Examples 1-3 and Comparative Examples 1-2 was tested; specifically: Leakage amount: Place each desiccant sample on a vibration table and vibrate at a frequency of 50 Hz and an amplitude of 1 mm for 30 min. Collect the released particulate matter and weigh it to record the leakage amount (mg).

[0068] Water absorption rate: First, weigh each desiccant sample before the test and record it as m1. Place each desiccant sample in an environment of 38℃ and 90% RH for 72 hours and then weigh it and record it as m2. Water absorption rate (%) = (m2-m1) / m1×100; and record the time it takes for the water absorption rate to reach 80%. The results are shown in Table 2.

[0069] Table 2 Desiccant Performance

[0070] As shown in Table 2, the desiccant formed by coating desiccant particles with the foldable packaging materials provided in Examples 1-3 of this application has a leakage amount of less than 10 mg, meeting the leak-proof requirements. The water absorption rate after 72 hours is all above 80%, demonstrating good air permeability. Furthermore, the time required to reach 80% water absorption is no more than 50 hours, indicating good water absorption efficiency. Comparing Examples 1-3, the foldable packaging materials provided in Examples 1-3 have progressively denser array-like rib structures pressed along the thickness direction of the packaging material on the buffer layer and leak-proof layer. This makes the packaging structure increasingly stable, preventing a decrease in air permeability due to folding or compaction, resulting in progressively higher water absorption rates and faster water absorption response times under dynamic usage conditions. In contrast, the packaging material provided in Comparative Example 1 lacks an array-like rib structure pressed along the thickness direction of the packaging material in its buffer layer and leak-proof layer. Folding or compaction can cause micropore collapse or structural densification, creating "dead zones" that hinder moisture transmission, thus reducing its water absorption rate and prolonging its water absorption response time. The packaging material provided in Comparative Example 2 does not include a breathable support layer, which reduces the overall structural strength of the packaging material. During hot pressing or actual use, it is more prone to interlayer slippage or local collapse, resulting in obstruction of the breathable channels. At the same time, the breathable control layer loses its support and may undergo local densification during hot pressing or folding, reducing the effective breathable area. In addition, without the breathable support layer, the overall packaging material lacks the "bridge" effect of the breathable support layer, making it difficult for moisture to efficiently penetrate the entire packaging material structure, thereby reducing the water absorption performance of the packaging material and prolonging the response time.

[0071] This application demonstrates that the foldable packaging material provided is suitable for use with desiccants, meeting both leak-proof requirements and exhibiting good air permeability and water absorption efficiency.

[0072] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A fold-resistant packaging material, characterized in that, The packaging material includes, from bottom to top, a breathable control layer, a breathable support layer, a buffer layer, and a leak-proof layer. The breathable control layer is used to contact the product to be packaged. The buffer layer and the leak-proof layer have an array of rib-like structures pressed together along the thickness direction of the packaging material. The strength of the breathable support layer is greater than that of the breathable control layer.

2. The fold-resistant packaging material according to claim 1, characterized in that, The rib-like structure is dot-like, and the dot-like rib-like structures are distributed in an array; or the rib-like structure is linear, and the linear rib-like structures are distributed in an array.

3. The fold-resistant packaging material according to claim 2, characterized in that, The rib-like structure is linear, and the linear rib-like structures are distributed in an array. Along the plane of the foldable packaging material, each row of linear rib-like structures forms an alternating V-shaped structure.

4. The fold-resistant packaging material according to claim 3, characterized in that, The rib structure is a composite structure of point and line structures. The point rib structures are distributed in an array, and the line rib structures are distributed in an array. A row of line rib structures is set between two adjacent rows of point rib structures.

5. The foldable packaging material according to any one of claims 1 to 4, characterized in that, The ratio of the sum of the thicknesses of the buffer layer and the leak-proof layer to the thickness of the breathable support layer is (3~10):

1.

6. The foldable packaging material according to any one of claims 1 to 4, characterized in that, The sum of the thicknesses of the buffer layer and the leak-proof layer is 65% to 85% of the total thickness of the foldable packaging material.

7. The fold-resistant packaging material according to claim 6, characterized in that, The combined thickness of the buffer layer and the leak-proof layer is 50~400 μm, and the mass per unit area is 30~100 g / m².

8. The fold-resistant packaging material according to claim 6, characterized in that, The total thickness of the fold-resistant packaging material is 70~500μm.

9. The fold-resistant packaging material according to claim 7, characterized in that, The thickness of the buffer layer is 40~300 μm, and the thickness of the leak-proof layer is 10~100 μm.

10. The foldable packaging material according to claim 1, characterized in that, The thickness of the breathable control layer is 10~100μm, and the thickness of the breathable support layer is 10~50μm.

11. The fold-resistant packaging material according to claim 10, characterized in that, The pore density of both the breathable control layer and the breathable support layer is 10~80 pores / cm², and the average pore diameter is 0.3~1.0 mm.

12. The fold-resistant packaging material according to claim 1, characterized in that, The leak-proof layer is selected from glass fiber filter paper, plant fiber filter paper, synthetic fiber filter paper or microporous membrane; the buffer layer is selected from spunbond nonwoven fabric, thermally rolled nonwoven fabric or meltblown nonwoven fabric; the breathable support layer is selected from polypropylene or polyethylene terephthalate; the breathable control layer is selected from polyethylene membrane or polypropylene membrane.

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