A moisture-proof and corrosion-proof packaging bag

Abstract

The utility model discloses a kind of damp-proof anticorrosive packaging bags, belong to packaging technical field, to solve the problem of poor moisture-proof performance of existing packaging bag, lack of anticorrosive function, low interlaminar bond strength. The packaging bag includes heat-seal inner layer, first adhesive layer, first moisture-proof layer, second adhesive layer, anticorrosive layer, third adhesive layer, second moisture-proof layer, fourth adhesive layer, wear-resistant outer layer in order from inside to outside. The packaging bag has excellent moisture-proof effect, each layer is connected by high peel strength adhesive layer, and the interlaminar combination is tight. It has good physical properties and use convenience, and is suitable for food, medicine, electronic components, metal parts and other products packaging with strict requirements on humidity and corrosivity, can prolong the shelf life and service life of goods, wide application range, high practicality and popularization value.

Description

Technical Field

[0001] This utility model relates to the field of packaging technology, specifically to a multi-layered packaging bag with dual functions of moisture-proof and corrosion-proof, which is particularly suitable for packaging scenarios of food, medicine, electronic components and metal parts where there are strict requirements for the humidity and corrosiveness of the storage environment. Background Technology

[0002] Packaging bags, as a common type of packaging container, are widely used in daily life, industrial production, and commercial trade. Their main functions are to protect, isolate, and facilitate the transportation and storage of the items they contain. Depending on the usage scenario and protection requirements, packaging bags exhibit diverse materials and structures, such as plastic bags, paper bags, and composite material bags. Among these, composite material bags are widely used in functional packaging because they combine the advantages of different individual materials. However, existing packaging bags still have significant shortcomings in terms of moisture and corrosion protection. On the one hand, traditional plastic or paper packaging bags, with their single material structure, are insufficient to effectively prevent the penetration of external moisture. When packaged goods are exposed to a humid environment for a long time, they are prone to problems such as dampness, mold, clumping, and performance failure. This is especially true for food and medicine, directly affecting their safety and usability. On the other hand, while some packaging bags consider moisture protection by using simple waterproof coatings or single barrier layers, they lack protection against corrosive substances (such as acidic gases and alkaline substances in the air). In certain environments (such as industrial plants and coastal areas with high salt spray), packaging bags are easily corroded and damaged, causing their protective function to fail. At the same time, corrosive substances may also penetrate into the packaging bag, causing corrosion and damage to the packaged goods. In addition, existing packaging bags with certain functions also need improvement in physical properties such as interlayer bonding strength and abrasion resistance, making it difficult to meet the needs of long-term storage and repeated handling. Utility Model Content

[0003] In view of the problems of poor moisture-proof performance, lack of anti-corrosion function, and low interlayer bonding strength of existing packaging bags, this utility model provides a moisture-proof and anti-corrosion packaging bag. Through the rational design of a multi-layer functional structure, it achieves excellent moisture-proof and anti-corrosion effects, while improving the overall physical properties of the packaging bag.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A moisture-proof and corrosion-resistant packaging bag comprises, from the inside out, a heat-sealed inner layer, a first adhesive layer, a first moisture-proof layer, a second adhesive layer, a corrosion-resistant layer, a third adhesive layer, a second moisture-proof layer, a fourth adhesive layer, and a wear-resistant outer layer. The heat-sealed inner layer is in direct contact with the packaged item. The first and second moisture-proof layers are located on both sides of the corrosion-resistant layer, forming a protective and double moisture-proof structure for the corrosion-resistant layer. The first, second, third, and fourth adhesive layers connect adjacent layers. The wear-resistant outer layer is located on the outermost side of the packaging bag, serving to prevent scratches and protect the internal structure.

[0005] Preferably, the heat-sealed inner layer is made of linear low-density polyethylene with a thickness of 50-80 μm.

[0006] Preferably, both the first and second moisture-proof layers are made of ethylene-vinyl alcohol copolymer, and the thickness of the first moisture-proof layer is 30-50 μm, while the thickness of the second moisture-proof layer is 25-40 μm.

[0007] Preferably, the anti-corrosion layer is a modified epoxy resin coating with a thickness of 15-25 μm; the modified epoxy resin coating is made by mixing epoxy resin, curing agent and anti-corrosion filler in a mass ratio of 100:15-25:5-10, wherein the anti-corrosion filler is a mixture of nano titanium dioxide and glass flakes, and the mass ratio of nano titanium dioxide to glass flakes is 1:2-3.

[0008] Preferably, the wear-resistant outer layer is made of biaxially oriented polypropylene with a thickness of 40-60 μm.

[0009] Preferably, the first adhesive layer, the second adhesive layer, the third adhesive layer, and the fourth adhesive layer are all made of polyurethane adhesive, and the thickness of each adhesive layer is 5-10 μm.

[0010] The beneficial effects of this utility model are: This utility model features a dual moisture-proof structure with a first moisture-proof layer and a second moisture-proof layer, both made of highly barrier ethylene-vinyl alcohol copolymer material. This effectively blocks the penetration of external water vapor and prevents oxygen from entering the packaging bag, thus avoiding spoilage of the packaged items due to moisture or oxidation. It is especially suitable for products such as food, medicine, and electronic components that are sensitive to humidity.

[0011] By setting a modified epoxy resin coating as an anti-corrosion layer, the nano-titanium dioxide and glass flake anti-corrosion filler added to the coating can form a dense anti-corrosion barrier inside the packaging bag, effectively resisting the erosion of acidic gases, alkaline substances and high salt spray environment in the air. This not only protects the packaging bag itself from corrosion and damage, but also prevents corrosive substances from penetrating into the interior and damaging the packaged items.

[0012] The heat-sealing inner layer is made of linear low-density polyethylene, which has excellent heat-sealing performance, making it easy to seal the packaging bag. It is also flexible and can fit tightly to the packaged items. The wear-resistant outer layer is made of biaxially oriented polypropylene, which has high tensile strength, good puncture resistance and scratch resistance, improving the packaging bag's resistance to damage and making it suitable for long-term storage and repeated handling.

[0013] The first, second, third, and fourth adhesive layers use polyurethane adhesive, which has high peel strength and ensures a tight bond between adjacent layers, avoiding the problem of interlayer separation during use and ensuring the overall structural stability of the packaging bag.

[0014] This utility model of moisture-proof and corrosion-resistant packaging bag can not only meet the packaging needs under normal conditions, but also adapt to special corrosive environments such as industrial plants and coastal areas with high salt spray, as well as the moisture-proof needs of humid and rainy areas. It can be widely used in the packaging of various products such as food, medicine, electronic components, metal parts, and precision instruments, and has high practicality and market promotion value. Attached Figure Description

[0015] Figure 1 This is a vertical cross-sectional view of a moisture-proof and corrosion-resistant packaging bag proposed in this utility model. Figure 2 for Figure 1 An enlarged schematic diagram of the structure at point A.

[0016] In the diagram: 1 heat-sealed inner layer, 2 first adhesive layer, 3 first moisture-proof layer, 4 second adhesive layer, 5 anti-corrosion layer, 6 third adhesive layer, 7 second moisture-proof layer, 8 fourth adhesive layer, 9 wear-resistant outer layer. Detailed Implementation

[0017] To make the technical solution of this utility model clearer and more explicit, the present utility model will be further described in detail below with reference to specific embodiments.

[0018] A moisture-proof and corrosion-resistant packaging bag comprises, from the inside out, a heat-sealed inner layer 1, a first adhesive layer 2, a first moisture-proof layer 3, a second adhesive layer 4, a corrosion-resistant layer 5, a third adhesive layer 6, a second moisture-proof layer 7, a fourth adhesive layer 8, and a wear-resistant outer layer 9. The parameters of each layer are as follows: Heat-sealed inner layer 1: linear low-density polyethylene (LLDPE), 50 μm thick, melt index 1.0 g / 10 min (test conditions: 190℃, 2.16 kg). First adhesive layer 2: polyurethane adhesive, 5μm thick, peel strength 3.0N / 15mm; First moisture-proof layer 3: Ethylene-vinyl alcohol copolymer (EVOH), ethylene content 25%, thickness 30μm; Second adhesive layer 4: polyurethane adhesive, 5μm thick, peel strength 3.0N / 15mm; Anti-corrosion layer 5: Modified epoxy resin coating, made of epoxy resin, curing agent, and nano titanium dioxide-glass flake mixture (mass ratio 1:2) mixed in a ratio of 100:15:5, with a thickness of 15μm; Third adhesive layer 6: polyurethane adhesive, 5μm thick, peel strength 3.0N / 15mm; Second moisture barrier 7: Ethylene-vinyl alcohol copolymer (EVOH), ethylene content 25%, thickness 25μm; Fourth adhesive layer 8: polyurethane adhesive, 5μm thick, peel strength 3.0N / 15mm; Wear-resistant outer layer 9: Biaxially oriented polypropylene (BOPP), thickness 40μm, tensile strength 250MPa (longitudinal), 220MPa (transverse), puncture resistance 30N, surface hardness HB.

[0019] Example 2 A moisture-proof and corrosion-resistant packaging bag comprises, from the inside out, a heat-sealed inner layer 1, a first adhesive layer 2, a first moisture-proof layer 3, a second adhesive layer 4, a corrosion-resistant layer 5, a third adhesive layer 6, a second moisture-proof layer 7, a fourth adhesive layer 8, and a wear-resistant outer layer 9. The parameters of each layer are as follows: Heat-sealed inner layer 1: linear low-density polyethylene (LLDPE), 65 μm thick, melt index 1.5 g / 10 min (test conditions: 190℃, 2.16 kg). First adhesive layer 2: polyurethane adhesive, 8μm thick, peel strength 3.5N / 15mm; First moisture-proof layer 3: Ethylene-vinyl alcohol copolymer (EVOH), ethylene content 30%, thickness 40μm; Second adhesive layer 4: polyurethane adhesive, 8μm thick, peel strength 3.5N / 15mm; Anti-corrosion layer 5: Modified epoxy resin coating, made of epoxy resin, curing agent, and nano titanium dioxide-glass flake mixture (mass ratio 1:2.5) mixed in a ratio of 100:20:8, with a thickness of 20μm; Third adhesive layer 6: polyurethane adhesive, 8μm thick, peel strength 3.5N / 15mm; Second moisture barrier 7: Ethylene-vinyl alcohol copolymer (EVOH), ethylene content 30%, thickness 32μm; Fourth adhesive layer 8: polyurethane adhesive, 8μm thick, peel strength 3.5N / 15mm; Wear-resistant outer layer 9: Biaxially oriented polypropylene (BOPP), thickness 50μm, tensile strength 260MPa (longitudinal), 230MPa (transverse), puncture resistance 35N, surface hardness HB.

[0020] Example 3 A moisture-proof and corrosion-resistant packaging bag comprises, from the inside out, a heat-sealed inner layer 1, a first adhesive layer 2, a first moisture-proof layer 3, a second adhesive layer 4, a corrosion-resistant layer 5, a third adhesive layer 6, a second moisture-proof layer 7, a fourth adhesive layer 8, and a wear-resistant outer layer 9. The parameters of each layer are as follows: Heat-sealed inner layer 1: linear low-density polyethylene (LLDPE), 80 μm thick, melt index 2.0 g / 10 min (test conditions: 190℃, 2.16 kg). First adhesive layer 2: polyurethane adhesive, 10μm thick, peel strength 4.0N / 15mm; First moisture-proof layer 3: Ethylene-vinyl alcohol copolymer (EVOH), ethylene content 35%, thickness 50μm; Second adhesive layer 4: polyurethane adhesive, 10μm thick, peel strength 4.0N / 15mm; Anti-corrosion layer 5: Modified epoxy resin coating, made of epoxy resin, curing agent, and nano titanium dioxide-glass flake mixture (mass ratio 1:3) mixed in a ratio of 100:25:10, with a thickness of 25μm; Third adhesive layer 6: polyurethane adhesive, 10μm thick, peel strength 4.0N / 15mm; Second moisture barrier 7: Ethylene-vinyl alcohol copolymer (EVOH), ethylene content 35%, thickness 40μm; Fourth adhesive layer 8: polyurethane adhesive, 10μm thick, peel strength 4.0N / 15mm; Wear-resistant outer layer 9: Biaxially oriented polypropylene (BOPP), thickness 60μm, tensile strength 270MPa (longitudinal), 240MPa (transverse), puncture resistance 40N, surface hardness HB; Adhesive layer: polyurethane adhesive, 10μm thick, peel strength 4.0N / 15mm. The performance of the moisture-proof and anti-corrosion packaging bags in Examples 1-3 above was tested, and the results are as follows: Moisture-proof performance: Water vapor transmission rate ≤0.5g / (m²) 2 • 24h (23℃, 85%RH), far superior to traditional plastic packaging bags (usually ≥5g / (m³)). 2 •24h) Corrosion resistance: The resistance to neutral salt spray is ≥1000h. After being placed in a salt spray environment for 1000h, the packaging bag is free from corrosion and damage, and the metal parts inside are free from rust. Physical properties: interlayer peel strength ≥3.0N / 15mm, puncture resistance ≥30N, after 100 rubbing tests, there is no interlayer separation or damage, which can meet the requirements of long-term use.

[0021] The above embodiments are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Any modifications and improvements made to the technical solutions of this utility model by those skilled in the art without departing from the spirit of this utility model should fall within the protection scope defined by the claims of this utility model.

Claims

1. A moisture-proof and corrosion-resistant packaging bag, characterized in that, From the inside out, it includes a heat-sealed inner layer (1), a first adhesive layer (2), a first moisture-proof layer (3), a second adhesive layer (4), an anti-corrosion layer (5), a third adhesive layer (6), a second moisture-proof layer (7), a fourth adhesive layer (8), and a wear-resistant outer layer (9). The heat-sealed inner layer (1) is in direct contact with the packaged item. The first moisture-proof layer (3) and the second moisture-proof layer (7) are located on both sides of the anti-corrosion layer (5), forming a protective and double moisture-proof structure for the anti-corrosion layer (5). The first adhesive layer (2), the second adhesive layer (4), the third adhesive layer (6), and the fourth adhesive layer (8) are connected to adjacent layers. The wear-resistant outer layer (9) is located on the outermost side of the packaging bag and plays a role in preventing scratches and protecting the internal structure.

2. The moisture-proof and corrosion-resistant packaging bag according to claim 1, characterized in that, The heat-sealed inner layer (1) is made of linear low-density polyethylene with a thickness of 50-80μm.

3. The moisture-proof and corrosion-resistant packaging bag according to claim 2, characterized in that, The first moisture-proof layer (3) and the second moisture-proof layer (7) are both made of ethylene-vinyl alcohol copolymer, and the thickness of the first moisture-proof layer (3) is 30-50μm, and the thickness of the second moisture-proof layer (7) is 25-40μm.

4. The moisture-proof and corrosion-resistant packaging bag according to claim 3, characterized in that, The wear-resistant outer layer (9) is made of biaxially oriented polypropylene with a thickness of 40-60 μm.

5. A moisture-proof and corrosion-resistant packaging bag according to claim 4, characterized in that, The first adhesive layer (2), the second adhesive layer (4), the third adhesive layer (6), and the fourth adhesive layer (8) are all made of polyurethane adhesive, and the thickness of each adhesive layer is 5-10 μm.

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