Cast film with high water vapor permeability

Abstract

The utility model discloses a cast film with high water vapor permeability, which comprises a cast film, a plurality of groups of water vapor permeability holes are equidistantly formed in the cast film, two adjacent groups of water vapor permeability holes are spaced by a certain distance, the cast film comprises a cast film main body, and the cast film main body comprises a first cast film main body, a property enhancing layer and a second cast film main body, the top of the cast film body is connected with the supporting layer through the adhesive layer, the first fireproof layer and the first PE layer are sequentially fixed to the outer side of the supporting layer in an adhesive mode, the second fireproof layer and the second PE layer are sequentially fixed to the bottom of the cast film body in an adhesive mode, and the first PE layer and the second PE layer are both made of films made of PE materials. According to the cast film with the high water vapor permeability, in order to solve the problems that an existing cast film is insufficient in toughness and prone to being damaged due to external tension, the cast film body is arranged, and the cast film body comprises the first cast film body, the performance increasing layer and the second cast film body.

Description

Technical Field

[0001] This utility model relates to the field of cast film technology, specifically a highly water-permeable cast film. Background Technology

[0002] Cast film is a non-stretched, non-oriented planar extrusion film produced by rapidly cooling a melt. It has two main production methods: single-layer casting and multi-layer co-extrusion. Compared to blown film, cast film offers faster production speeds, higher output, and excellent transparency, gloss, and thickness uniformity. Cast film possesses superior heat-sealing properties and excellent transparency, making it one of the main packaging composite substrates, commonly used in the production of high-temperature retort films and vacuum metallized films. Furthermore, cast film is widely used in the packaging of food, pharmaceuticals, textiles, and daily necessities because subsequent processes such as printing and lamination are very convenient.

[0003] A search revealed an existing technology, such as CN207418655U, which describes a cast film comprising a heat-sealing layer, a support layer, and a corona layer. The support layer is a polytetrafluoroethylene (PTFE) microporous membrane, with each micropore on its inner wall having an outwardly expanding curved surface. The micropore diameter of the PTFE microporous membrane is 0.2-0.3 micrometers. The edges of the support layer have a stretched structure, and the thickness in the middle of the support layer is greater than the thickness at the edges. This cast film is breathable yet waterproof, exhibiting excellent water resistance.

[0004] In summary, existing cast films have good water resistance, but they lack toughness and are easily damaged by external tension. Therefore, a high water vapor permeability cast film is proposed. Utility Model Content

[0005] The purpose of this invention is to provide a highly water-permeable cast film to solve the problem mentioned in the background art of insufficient toughness of existing cast films, which are easily damaged by external tension.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a highly water-permeable cast film, comprising a cast film, wherein a plurality of sets of water-permeable holes are equidistantly opened on the cast film, and adjacent sets of water-permeable holes are spaced apart by a distance; the cast film comprises a cast film body, and the cast film body comprises a first cast film body, an adhesive layer and a second cast film body; the top of the cast film body is connected to a support layer through an adhesive layer, and a first fireproof layer and a first PE layer are sequentially adhered and fixed to the outside of the support layer; a second fireproof layer and a second PE layer are sequentially adhered and fixed to the bottom of the cast film body; the first PE layer and the second PE layer are both made of PE film.

[0007] Preferably, the adhesive layer is bonded and fixed to the inner side of the first cast film body and the second cast film body.

[0008] The above technical solutions improve the toughness of cast film.

[0009] Preferably, both the first cast film substrate and the second cast film substrate are polyethylene-vinyl acetate film layers.

[0010] The above technical solution facilitates the production of cast films.

[0011] Preferably, the reinforcing layer includes a nylon plastic layer, and a cotton mesh layer is wrapped and fixed on the outside of the nylon plastic layer. Multiple sets of glass fiber filaments are distributed inside the nylon plastic layer, and the glass fiber filaments are distributed at equal intervals.

[0012] The above technical solutions improve the toughness of cast film.

[0013] Preferably, the support layer is made of polytetrafluoroethylene microporous membrane.

[0014] The above technical solutions improve the support of the cast film.

[0015] Preferably, both the first fireproof layer and the second fireproof layer are made of ceramic fiber paper.

[0016] The above technical solutions improve the fire resistance of cast film.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows: This high water vapor permeability cast film, in order to solve the problem of insufficient toughness of existing cast films and easy damage caused by external tensile force, is achieved by setting a cast film body, which includes a first cast film body, a reinforcing layer and a second cast film body. The reinforcing layer includes a nylon plastic layer, and a cotton mesh layer is wrapped and fixed on the outside of the nylon plastic layer. Multiple sets of glass fiber filaments are distributed inside the nylon plastic layer, and the glass fiber filaments are distributed at equal intervals. The top of the cast film body is connected to the support layer through an adhesive layer, and a first fireproof layer and a first PE layer are sequentially adhered and fixed on the outside of the support layer. The addition of the nylon plastic layer increases the tensile strength and environmental adaptability of the cast film, and the addition of glass fiber filaments to the nylon plastic layer and the reinforcing layer further enhances the toughness and improves the ability to resist external tensile force. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall front cross-sectional structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the main structure of the cast film of this utility model;

[0020] Figure 3 This is a schematic diagram of the additive layer structure of this utility model.

[0021] In the diagram: 1. Cast film; 101. Water vapor permeable pores; 2. Cast film body; 201. First cast film body; 202. Adhesive layer; 2021. Nylon plastic layer; 2022. Cotton web layer; 2023. Glass fiber filament; 203. Second cast film body; 3. Adhesive layer; 4. Support layer; 5. First fireproof layer; 6. First PE layer; 7. Second fireproof layer; 8. Second PE layer. Detailed Implementation

[0022] 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.

[0023] Please see Figure 1-3 This utility model provides a technical solution: a highly water-permeable cast film, the cast film 1 includes a cast film body 2, the top of the cast film body 2 is connected to the support layer 4 through an adhesive layer 3, and a first fireproof layer 5 and a first PE layer 6 are sequentially bonded and fixed to the outside of the support layer 4, and a second fireproof layer 7 and a second PE layer 8 are sequentially bonded and fixed to the bottom of the cast film body 2.

[0024] To further explain, several sets of water vapor permeable holes 101 are equally spaced on the cast film 1, and there is a distance between adjacent sets of water vapor permeable holes 101. By setting several sets of water vapor permeable holes 101, it is easy for water vapor to penetrate later. The distance between adjacent sets of water vapor permeable holes 101 can avoid the strength of the cast film 1 from decreasing due to the spacing of the water vapor permeable holes 101 being too close.

[0025] Specifically, the cast film body 2 includes a first cast film body 201, a reinforcing layer 202, and a second cast film body 203. The reinforcing layer 202 is adhered and fixed to the inner side of the first cast film body 201 and the second cast film body 203. Both the first cast film body 201 and the second cast film body 203 are polyethylene-vinyl acetate film layers. The reinforcing layer 202 includes a nylon plastic layer 2021, and a cotton mesh layer 2022 is wrapped and fixed on the outside of the nylon plastic layer 2021. Multiple sets of glass fiber filaments 2023 are distributed inside the nylon plastic layer 2021, and the glass fiber filaments 2023 are evenly distributed. The setting of the nylon plastic layer 2021 increases the tensile strength and environmental adaptability of the cast film 1. Furthermore, the addition of glass fiber filaments 2023 to the nylon plastic layer 2021 and the reinforcing layer 202 further enhances the toughness and improves the ability to resist external tensile forces.

[0026] Specifically, the support layer 4 is made of polytetrafluoroethylene microporous membrane. The polytetrafluoroethylene membrane is a semi-finished product obtained by extruding polytetrafluoroethylene rods and strips, calendering them into thin films, stretching and heat-setting them at a temperature below the melting point, and obtaining porous products with micropore diameters of 0.2-0.3 micrometers, which is smaller than the diameter of mist droplets but much larger than the diameter of water vapor molecules. Therefore, it allows gas molecules to pass through while hindering the passage of mist droplets, giving the film a certain degree of breathability and waterproofness. The support layer 4 mainly plays a supporting role for the cast film 1 and improves the structural strength of the film.

[0027] In a further embodiment, both the first fireproof layer 5 and the second fireproof layer 7 are made of ceramic fiber paper. Ceramic fiber is a fibrous, lightweight refractory material with the advantages of light weight, high temperature resistance, good thermal stability, low thermal conductivity, low specific heat and resistance to mechanical vibration. It can effectively prevent damage to the product caused by open flame and increase the protection of the product.

[0028] In a further embodiment, both the first PE layer 6 and the second PE layer 8 are made of PE film. PE film can protect the product from pollution, corrosion and scratches during production, processing, transportation, storage and use, and has a certain protective effect on the product.

[0029] The terms “center,” “longitudinal,” “lateral,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are merely simplified descriptions for the convenience of describing this utility model 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 limiting the scope of protection of this utility model.

[0030] 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 water vapor permeable cast film comprising a cast film (1), characterized in that: The cast film (1) has several sets of water vapor permeable holes (101) evenly spaced on it, and there is a distance between two adjacent sets of water vapor permeable holes (101). The cast film (1) includes a cast film body (2), and the cast film body (2) includes a first cast film body (201), an adhesive layer (202) and a second cast film body (203). The top of the cast film body (2) is connected to the support layer (4) through an adhesive layer (3), and a first fireproof layer (5) and a first PE layer (6) are sequentially bonded and fixed on the outside of the support layer (4). The bottom of the cast film body (2) is sequentially bonded and fixed with a second fireproof layer (7) and a second PE layer (8). The first PE layer (6) and the second PE layer (8) are both made of PE film.

2. The high water vapor permeable casting film according to claim 1, characterized in that: The enhancement layer (202) is adhered and fixed to the inner side of the first cast film body (201) and the second cast film body (203).

3. The high water vapor permeable casting film according to claim 1, characterized in that: Both the first cast film body (201) and the second cast film body (203) are polyethylene-vinyl acetate film layers.

4. The high water vapor permeable casting film according to claim 1, characterized in that: The reinforcing layer (202) includes a nylon plastic layer (2021), and a cotton mesh layer (2022) is wrapped and fixed on the outside of the nylon plastic layer (2021). Multiple sets of glass fiber filaments (2023) are distributed inside the nylon plastic layer (2021), and the glass fiber filaments (2023) are equidistantly distributed.

5. The high water vapor permeable casting film according to claim 1, characterized in that: The support layer (4) is made of polytetrafluoroethylene microporous membrane.

6. The high water vapor permeable casting film according to claim 1, characterized in that: Both the first fireproof layer (5) and the second fireproof layer (7) are made of ceramic fiber paper.

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