Easily tearable composite film

Abstract

The utility model provides a kind of easy tear composite film, the easy tear composite film includes the modified biaxially oriented PET film layer of laminated arrangement, first extrusion resin layer, aluminium layer and second extrusion resin layer;The structure formed by sandpaper pressure roller is covered on the both sides of the modified biaxially oriented PET film layer;The mesh number of sandpaper is 180-240 mesh number.Through the modified biaxially oriented PET film layer of laminated arrangement, first extrusion resin layer, aluminium layer and second extrusion resin layer, not only realize the easy tear effect of composite film, can also ensure that composite film optical performance and appearance are not influenced, satisfy medicine packaging function, improve the use experience of consumer.

Description

Technical Field

[0001] This utility model belongs to the field of packaging technology and relates to an easy-tear composite film. Background Technology

[0002] In today's trend towards lightweight packaging, pharmaceutical packaging is shifting from traditional metal and glass materials to plastic composite film packaging. Plastic composite film packaging, with its lightweight and portable characteristics, brings numerous conveniences to the transportation and use of pharmaceuticals, and is gradually becoming the mainstream choice for pharmaceutical packaging. However, in practical use, plastic composite film packaging has a significant problem: it is difficult to tear. This not only inconveniences consumers but also affects the efficiency of pharmaceutical use and the user experience.

[0003] Traditional plastic composite film packaging requires additional punching or cutting to facilitate tearing by the user. While this method solves the problem to some extent, it also brings several drawbacks. On the one hand, punching or cutting increases the complexity of packaging production, requiring additional equipment and processes, thus increasing production costs. On the other hand, this method also reduces the overall aesthetics and airtightness of the packaging, potentially adversely affecting the preservation and transportation of medicines.

[0004] With the market's increasing demands for packaging materials, especially for convenience and efficiency, developing a composite film that can be easily torn without additional processing has become a pressing issue for those skilled in the art. Utility Model Content

[0005] To address the shortcomings of existing technologies, the purpose of this utility model is to provide an easy-tear composite film. By layering a modified biaxially oriented PET film layer, a first extruded resin layer, an aluminum layer, and a second extruded resin layer, the composite film not only achieves an easy-tear effect but also ensures that its optical properties and appearance are not affected, thus fulfilling the function of pharmaceutical packaging and enhancing the consumer's user experience.

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

[0007] In a first aspect, this utility model provides an easy-tear composite film, which includes a modified biaxially oriented PET film layer, a first extruded resin layer, an aluminum layer, and a second extruded resin layer stacked together.

[0008] Both sides of the modified biaxially oriented PET film layer are covered with a structure formed by sandpaper rollers;

[0009] The grit of the sandpaper is 180-240 grit, for example, it can be 185 grit, 190 grit, 195 grit, 200 grit, 205 grit, 210 grit, 215 grit, 220 grit, 225 grit, 230 grit or 235 grit, but it is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0010] The easy-tear composite film provided by this utility model achieves an easy-tear effect for the PET film by rolling sandpaper on both sides of the biaxially oriented PET film, while ensuring that the optical properties and appearance of the film are not affected. Then, the modified biaxially oriented PET film is subjected to a first extrusion lamination, in which the modified biaxially oriented PET film layer is laminated with an aluminum layer through a first extrusion resin layer. Then, a second extrusion lamination is performed, in which a second extrusion resin layer is coated on the surface of the aluminum layer. The high temperature environment of the extrusion lamination process generates more internal stress in the film. After the film cools, the internal stress makes it more brittle, thus making it easier to tear.

[0011] It should be noted that by using sandpaper with a mesh size of 180-240 to roll-press both sides of the biaxially oriented PET film, the protruding particles on the sandpaper can make the biaxially oriented PET film easy to tear under the action of the pressure roller. The lower the mesh size, the more dispersed the distribution of protruding particles per unit area, the greater the point pressure on the film, and the better the tear-off effect. By controlling the mesh size range of the sandpaper, the tear-off effect after sandpaper rolling can be achieved relatively well without damaging the integrity of the biaxially oriented PET film too much, so that the optical properties and appearance of the film are not affected.

[0012] As a preferred technical solution of this utility model, the thickness of the modified biaxially oriented PET film layer is 12-50μm, for example, it can be 15μm, 16μm, 18μm, 20μm, 25μm, 30μm, 35μm, 40μm or 45μm, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0013] As a preferred technical solution of this utility model, the biaxially oriented PET film layer is a single-sided printed biaxially oriented PET film.

[0014] In this invention, printing can be performed on one side of the PET film according to customer requirements.

[0015] As a preferred technical solution of this utility model, the first extruded resin layer is a PE resin adhesive layer.

[0016] In this invention, the first extruded resin layer comprises the following components: PE resin, AE agent, and AC agent.

[0017] It should be noted that the modified biaxially oriented PET film layer and aluminum layer are directly bonded by the PE resin-containing material through extrusion lamination. This lamination method uses molten resin for bonding, which is different from the interface bonding method of dry lamination. The first extruded resin layer is more rigid but also more brittle, making the resulting composite film easier to tear. In addition, the high-temperature processing of extrusion lamination will weaken the local interface and form easy-tear paths.

[0018] As a preferred technical solution of this utility model, the thickness of the first extruded resin layer is 15-40μm, for example, it can be 16μm, 18μm, 20μm, 22μm, 25μm, 26μm, 28μm, 30μm, 32μm, 35μm, 36μm or 38μm, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0019] As a preferred technical solution of this utility model, the thickness of the aluminum layer is 7-20μm, for example, it can be 8μm, 10μm, 12μm, 14μm, 15μm, 16μm, 18μm or 19μm, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0020] As a preferred embodiment of this invention, the second extruded resin layer is a PE resin adhesive layer.

[0021] In this invention, the second extruded resin layer comprises the following components: PE resin and AC agent.

[0022] As a preferred technical solution of this utility model, the thickness of the second extruded resin layer is 15-40μm, for example, it can be 16μm, 18μm, 20μm, 22μm, 25μm, 26μm, 28μm, 30μm, 32μm, 35μm, 36μm or 38μm, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0023] This utility model also provides a method for preparing an easy-tear composite film, the method comprising the following steps:

[0024] (1) A single-sided printed biaxially oriented PET film is rolled on the front side and the back side in sequence to obtain a modified biaxially oriented PET film layer.

[0025] In both the front and back roll pressing processes, the surface of the pressure rollers is covered with sandpaper, and the printing rollers are all smooth rollers; the sandpaper has a mesh size of 180-240.

[0026] The method of front-side roll pressing includes: inserting the printed side of a single-sided printed biaxially oriented PET film between a pressure roller and a printing roller, and performing front-side roll pressing at a speed of 100-120 m / min and a pressure of 0.2-0.5 bar;

[0027] The reverse roll pressing method includes: inserting the non-printed side of a single-sided printed biaxially oriented PET film between a pressure roller and a printing roller, and performing reverse roll pressing at a speed of 125-150 m / min and a pressure of 0.2-0.5 bar;

[0028] (2) The first extrusion resin is placed in the extrusion device and melt-extruded between the modified biaxially oriented PET film layer and the aluminum foil. The first extrusion composite is carried out under the action of the cooling roller and the pressure roller. After cooling and winding, a modified biaxially oriented PET film layer / first extrusion resin layer / aluminum layer composite film is obtained.

[0029] In the first extrusion compounding process, the melt extrusion temperature is 180-230℃ and the speed is 200-300 kg / h;

[0030] The first extrusion compounding speed is 120-150 m / min; the cooling temperature in the first extrusion compounding is 40-50℃;

[0031] (3) The second extrusion resin is placed in the extrusion device, and after the second extrusion composite, it is coated on the aluminum layer surface of the composite film in step (2). After cooling and winding, a modified biaxially oriented PET film layer / first extrusion resin layer / aluminum layer second extrusion resin layer composite film is obtained. Then, it is cured and cut in sequence to obtain the easy-tear composite film.

[0032] In the second extrusion compounding process, the melt extrusion temperature is 250-330℃ and the speed is 300-350 kg / h;

[0033] In the second extrusion compounding process, the cooling temperature is 40-50℃.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The easy-tear composite film provided by this utility model includes a modified biaxially oriented PET film layer, a first extrusion resin layer, an aluminum layer and a second extrusion resin layer stacked together. By pressing both sides of the biaxially oriented PET film with sandpaper rollers, not only can the easy-tear effect of the PET film be achieved, but also the optical performance and appearance of the film can be ensured not to be affected. Then, the modified biaxially oriented PET film after processing is subjected to the first extrusion coating, and the modified biaxially oriented PET film layer is composited with the aluminum layer through the first extrusion resin layer. Then, the second extrusion coating is performed, and the second extrusion resin layer is coated on the surface of the aluminum layer. The high temperature environment of the extrusion coating process causes more internal stress to be generated inside the film. The internal stress will make the film more fragile after cooling, thus making it easier to tear.

[0036] (2) The easy-tear composite film provided by this utility model has good transverse and longitudinal tearability, low transverse and longitudinal tear strength, tensile strength in the range of 25-40MPa, and elongation at break in the range of 50%-70%, which improves the user experience of consumers. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the easy-tear composite film provided in Example 1;

[0038] Among them, 1-modified biaxially oriented PET film layer, 2-first extruded resin layer, 3-aluminum layer, 4-second extruded resin layer. Detailed Implementation

[0039] It should be understood that in the description of this utility model, the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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 utility model.

[0040] It should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" 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 mechanical connection or an electrical 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 utility model based on the specific circumstances.

[0041] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0042] In Example 1 below, the PE resin is 722 resin, purchased from Dow Chemical LDPE; the AC agent used is purchased from Henkel 4501; and the AE agent used is purchased from Dow Chemical EAA3990.

[0043] Example 1

[0044] This embodiment provides an easy-tear composite film, wherein the easy-tear composite film (such as...) Figure 1 (As shown) includes a modified biaxially oriented PET film layer 1, a first extruded resin layer 2, an aluminum layer 3, and a second extruded resin layer 4, which are stacked together.

[0045] Both sides of the modified biaxially oriented PET film layer 1 are covered with a structure formed by sandpaper pressure rollers; the sandpaper has a mesh size of 210; the thickness of the modified biaxially oriented PET film layer 1 is 25 μm; the biaxially oriented PET film layer is a single-sided printed biaxially oriented PET film.

[0046] The first extruded resin layer 2 is a PE resin adhesive layer with a thickness of 25 μm;

[0047] The thickness of the aluminum layer 3 is 15 μm;

[0048] The second extruded resin layer 4 is a PE resin adhesive layer with a thickness of 25μm.

[0049] This embodiment also provides a method for preparing an easy-tear composite film, the method comprising the following steps:

[0050] (1) A single-sided printed biaxially oriented PET film is rolled on the front side and the back side in sequence to obtain a modified biaxially oriented PET film layer.

[0051] In both the front and back roll pressing processes, the surface of the pressure rollers is covered with sandpaper, and the printing rollers are all smooth rollers; the sandpaper has a mesh size of 210.

[0052] The method of front-side roll pressing includes: inserting the printing surface of a single-sided printed biaxially oriented PET film between a pressure roller and a printing roller, and performing front-side roll pressing at a speed of 110 m / min and a pressure of 0.3 bar;

[0053] The reverse roll pressing method includes: inserting the non-printed side of a single-sided printed biaxially oriented PET film between a pressure roller and a printing roller, and performing reverse roll pressing at a speed of 140 m / min and a pressure of 0.3 bar;

[0054] (2) The first extrusion resin is placed in the extrusion device and melt-extruded between the modified biaxial PET film layer and the aluminum foil. Under the action of the cooling roller and the pressure roller, the first extrusion composite is carried out at a speed of 135 m / min. After cooling and winding at a temperature of 45°C, the modified biaxial PET film layer / first extrusion resin layer / aluminum layer composite film is obtained.

[0055] The first extrusion resin comprises the following components: PE resin, AE agent, and AC agent; the weight ratio of the PE resin to the adhesive is 4:1; the dry weight of the AC agent is 0.4 g / m³. 2 ;

[0056] In the first extrusion compounding process, the melt extrusion temperature is 220℃ and the speed is 250kg / h;

[0057] (3) The second extrusion resin is placed in the extrusion device, and after the second extrusion composite, it is coated on the aluminum layer surface of the composite film in step (2). After cooling and winding at a temperature of 45°C, a modified biaxially oriented PET film layer / first extrusion resin layer / aluminum layer second extrusion resin layer composite film is obtained. Then, it is cured and cut in sequence to obtain the easy-tear composite film.

[0058] The second extrusion resin comprises the following components: PE resin and AC agent; the PE resin is 100 parts by weight; the AC agent has a dry coating weight of 0.4 g / m³. 2 ;

[0059] In the second extrusion compounding process, the melt extrusion temperature is 300℃ and the speed is 320kg / h.

[0060] Example 2

[0061] This embodiment provides an easy-tear composite film, which includes a modified biaxially oriented PET film layer, a first extruded resin layer, an aluminum layer, and a second extruded resin layer stacked together.

[0062] The modified biaxially oriented PET film layer has a structure formed by sandpaper rollers on both sides; the sandpaper has a mesh size of 240; the thickness of the modified biaxially oriented PET film layer is 45 μm; the biaxially oriented PET film layer is a single-sided printed biaxially oriented PET film.

[0063] The first extruded resin layer is a PE resin adhesive layer with a thickness of 32 μm;

[0064] The thickness of the aluminum layer is 18 μm;

[0065] The second extruded resin layer is a PE resin adhesive layer with a thickness of 30μm.

[0066] Example 3

[0067] This embodiment provides an easy-tear composite film, which includes a modified biaxially oriented PET film layer, a first extruded resin layer, an aluminum layer, and a second extruded resin layer stacked together.

[0068] Both sides of the modified biaxially oriented PET film layer are covered with a structure formed by sandpaper rollers; the sandpaper has a mesh size of 180; the thickness of the modified biaxially oriented PET film layer is 20 μm; the biaxially oriented PET film layer is a single-sided printed biaxially oriented PET film.

[0069] The first extruded resin layer is a PE resin adhesive layer with a thickness of 20 μm;

[0070] The thickness of the aluminum layer is 10 μm;

[0071] The second extruded resin layer is a PE resin adhesive layer with a thickness of 18μm.

[0072] Comparative Example 1

[0073] This comparative example provides an easy-tear composite film, except that the sandpaper is 120 mesh; all other conditions are the same as in Example 1.

[0074] Comparative Example 2

[0075] This comparative example provides an easy-tear composite film, except that the sandpaper is 300 mesh; all other conditions are the same as in Example 1.

[0076] Comparative Example 3

[0077] This comparative example provides an easy-tear composite film, except that one side of the modified biaxially oriented PET film layer is covered with a structure formed by a sandpaper roller; all other conditions are the same as in Example 1.

[0078] Comparative Example 4

[0079] This comparative example provides an easy-tear composite film, except that the modified biaxially oriented PET film layer is replaced with a biaxially oriented PET film layer; all other conditions are the same as in Example 1.

[0080] Comparative Example 5

[0081] This comparative example provides an easy-tear composite film, except that the first extruded resin layer and the second extruded resin layer are replaced with the first adhesive resin layer and the second adhesive resin layer, that is, dry lamination is used instead of extrusion lamination; all other conditions are the same as in Example 1.

[0082] The composite films described in the above embodiments and comparative examples were subjected to tear resistance tests using the same dimensions. For the drop hammer impact test, the prepared easy-tear composite films were cut into 10cm × 10cm pieces and then tested using a drop hammer impact testing machine. For the tensile strength test, the prepared easy-tear composite films were cut into strips with a width of 15mm and then tested using a tensile testing machine with a tensile speed of 500mm / min and a gauge length of 50mm. The tensile strength and elongation at break of the composite film were recorded. The results are shown in Table 1.

[0083] Table 1

[0084]

[0085] (1) The easy-tear composite film provided in Embodiments 1-3 of this utility model includes a modified biaxially oriented PET film layer, a first extruded resin layer, an aluminum layer, and a second extruded resin layer stacked together. The PET composite film can be easily torn without additional treatment, which not only achieves the function of easy tearing, but also ensures the optical performance and appearance of the composite film, meets the packaging functions of various products, and improves the user experience of consumers; wherein, the drop hammer impact is as low as 0g, the tensile strength is in the range of 25-40MPa, and the elongation at break is in the range of 50%-70%.

[0086] (2) Comparing Example 1 and Comparative Examples 1-2, it can be seen that if the sandpaper mesh number is too small, the pressure on the film per unit area is large, resulting in low tensile strength and elongation at break of the composite film, making it easy to break and unsuitable for subsequent packaging use; if the sandpaper mesh number is too large, the pressure on the film per unit area is small, resulting in high tensile strength and elongation at break of the composite film, which cannot achieve good tear-resistant properties of the composite film.

[0087] (3) Comparison of Example 1 and Comparative Examples 3-4 shows that if a biaxially stretched PET film layer or a structure formed by sandpaper rollers on only one side is used, the easy-tear performance of the PET composite film cannot be well achieved, resulting in an increase in the tensile strength and elongation at break of the composite film.

[0088] (5) Comparing Example 1 and Comparative Example 5, it can be seen that if dry composite is used, the strong adhesive layer formed after the dry composite is cured will increase the tear resistance. In addition, the multi-layer structure in the dry composite will also increase the tear resistance due to the synergistic force, resulting in an increase in the tensile strength and elongation at break of the composite film, which cannot achieve the easy tear performance of the composite film.

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

Claims

1. An easy-tear composite film, characterized in that, The easy-tear composite film comprises a modified biaxially oriented PET film layer, a first extruded resin layer, an aluminum layer, and a second extruded resin layer, which are stacked together. Both sides of the modified biaxially oriented PET film layer are covered with a structure formed by sandpaper rollers; The sandpaper has a mesh size of 180-240.

2. The easy-tear composite film according to claim 1, characterized in that, The thickness of the modified biaxially oriented PET film is 12-50 μm.

3. The easy-tear composite film according to claim 1, characterized in that, The biaxially oriented PET film is a single-sided printed biaxially oriented PET film.

4. The easy-tear composite film according to claim 1, characterized in that, The first extruded resin layer is a PE resin adhesive layer.

5. The easy-tear composite film according to claim 1, characterized in that, The thickness of the first extruded resin layer is 15-40 μm.

6. The easy-tear composite film according to claim 1, characterized in that, The thickness of the aluminum layer is 7-20 μm.

7. The easy-tear composite film according to claim 1, characterized in that, The second extruded resin layer is a PE resin adhesive layer.

8. The easy-tear composite film according to claim 1, characterized in that, The thickness of the second extruded resin layer is 15-40 μm.

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