Medical tearable film and method of making same

Abstract

A medical easy-to-tear film and a manufacturing method thereof are disclosed. The medical easy-to-tear film comprises a release layer and an auxiliary layer. The release layer comprises a propylene block polymer and an ethylene polymer. The content of the propylene block polymer is between 60 wt% and 80 wt% and the content of the ethylene polymer is between 20 wt% and 40 wt% based on the total weight of the release layer being 100 wt%. The auxiliary layer comprises a propylene block polymer and a propylene random copolymer. The content of the propylene block polymer is between 90 wt% and 99 wt% and the content of the propylene random copolymer is between 1 wt% and 10 wt% based on the total weight of the auxiliary layer being 100 wt%. The medical easy-to-tear film has a heat seal strength of between 5 N / 15 mm and 15 N / 15 mm after 30 minutes in an environment of 135 °C.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of tearable film and its manufacturing method, in particular to a kind of medical tearable film and its manufacturing method. BACKGROUND

[0002] The existing tearable film is mostly applied to the product only needing to pass through low-temperature sterilization, if frozen or pudding, and the composition of the existing tearable film is generally mainly polyethylene, so the existing tearable film is not high enough in heat resistance, cannot be applied to the product needing to pass through high-temperature sterilization. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a kind of medical tearable film and its manufacturing method, which can effectively solve the problem that the existing tearable film cannot be applied to the product needing to pass through high-temperature sterilization.

[0004] In order to solve the above technical problems, one of the technical solutions adopted by the present application is to provide a kind of medical tearable film, which comprises: a release layer comprising propylene block polymer and ethylene polymer; wherein, based on the total weight of the release layer being 100wt%, the content of the propylene block polymer is between 60wt% and 80wt%, and the content of the ethylene polymer is between 20wt% and 40wt%; and an auxiliary layer comprising propylene block polymer and propylene random copolymer; wherein, based on the total weight of the auxiliary layer being 100wt%, the content of the propylene block polymer is between 90wt% and 99wt%, and the content of the propylene random copolymer is between 1wt% and 10wt%; wherein, the heat seal strength of the medical tearable film after 30 minutes in an environment of 135℃ is between 5N / 15mm and 15N / 15mm.

[0005] Preferably, an island structure is formed in the release layer, the island structure comprises a sea phase and an island phase, the propylene block polymer is defined as the sea phase, and the ethylene polymer is defined as the island phase.

[0006] Preferably, in the release layer, the propylene block polymer comprises propylene monomer and ethylene-propylene polymer, based on the total weight of the propylene block polymer being 100wt%, the content of the propylene monomer is between 75wt% and 85wt%, and the content of the ethylene-propylene polymer is between 15wt% and 25wt%.

[0007] Preferably, in the propylene block polymer, the ethylene-propylene polymer is dispersed in the propylene monomer to form an island structure; wherein, the island structure comprises a sea phase and an island phase, the propylene monomer is defined as the sea phase, and the ethylene-propylene polymer is defined as the island phase.

[0008] Preferably, the ethylene polymer is at least one selected from the group of materials consisting of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and high density polyethylene (HDPE).

[0009] Preferably, in the auxiliary layer, the propylene block polymer comprises propylene monomer and ethylene-propylene polymer, the content of the propylene monomer is between 75wt% and 85wt%, and the content of the ethylene-propylene polymer is between 15wt% and 25wt%, based on the total weight of the propylene block polymer being 100wt%.

[0010] Preferably, the propylene random copolymer is formed by polymerization of propylene monomer and ethylene monomer, and the content of the propylene monomer is between 98wt% and 99.99wt%, and the content of the ethylene monomer is between 0.01wt% and 2wt%, based on the total weight of the propylene random copolymer being 100wt%.

[0011] Preferably, the content of the propylene block polymer is between 95wt% and 99wt%, and the content of the propylene random copolymer is between 1wt% and 5wt%, based on the total weight of the auxiliary layer being 100wt%.

[0012] Preferably, the thickness of the peeling layer is 20% to 40% of the thickness of the medical tearable film, and the thickness of the auxiliary layer is 40% to 80% of the thickness of the medical tearable film.

[0013] Preferably, the heat seal strength of the medical tearable film after 30 minutes in an environment of 135℃ is between 8N / 15mm and 12N / 15mm; wherein the medical tearable film is a solution tearable film for contact lenses.

[0014] To solve the above technical problems, another technical scheme adopted by the present application is to provide a manufacturing method of a medical tearable film, which comprises: a preparation step: preparing a propylene block polymer, an ethylene polymer and a propylene random copolymer; wherein the propylene block polymer comprises propylene monomers and ethylene-propylene polymers, the ethylene-propylene polymers are dispersed in the propylene monomers to form an island-in-the-sea structure, the island-in-the-sea structure comprises a sea phase and an island phase, the propylene monomers are defined as the sea phase, and the ethylene-propylene polymers are defined as the island phase; a co-extrusion step: forming a medical tearable film by co-extruding the propylene block polymer, the ethylene polymer and the propylene random copolymer, the medical tearable film comprises a peeling layer and an auxiliary layer; wherein the peeling layer comprises the propylene block polymer and the ethylene polymer, based on the total weight of the peeling layer being 100 wt%, the content of the propylene block polymer is between 60 wt% and 80 wt%, and the content of the ethylene polymer is between 20 wt% and 40 wt%; wherein the auxiliary layer comprises the propylene block polymer and the propylene random copolymer, based on the total weight of the auxiliary layer being 100 wt%, the content of the propylene block polymer is between 90 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 10 wt%; wherein the heat sealing strength of the medical tearable film after 30 minutes in an environment of 135°C is between 5 N / 15 mm and 15 N / 15 mm.

[0015] Preferably, an island-in-the-sea structure is formed in the peeling layer, the island-in-the-sea structure comprises a sea phase and an island phase, the propylene block polymer is defined as the sea phase, and the ethylene polymer is defined as the island phase.

[0016] Preferably, in the preparation step, based on the total weight of the propylene block polymer being 100 wt%, the content of the propylene monomers is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymers is between 15 wt% and 25 wt%.

[0017] Preferably, in the preparation step, the ethylene polymer is at least one selected from the material group consisting of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE).

[0018] Preferably, in the preparation step, the propylene random copolymer is formed by polymerization of propylene monomers and ethylene monomers, and based on the total weight of the propylene random copolymer being 100 wt%, the content of the propylene monomers is between 98 wt% and 99.99 wt%, and the content of the ethylene monomers is between 0.01 wt% and 2 wt%.

[0019] One of the beneficial effects of the present invention is that the medical easy-tear film and its manufacturing method provided by the present invention can improve the problem that existing easy-tear films cannot be applied to products that need to undergo high-temperature sterilization by means of the technical solutions of "based on the total weight of the peeling layer being 100wt%, the content of the propylene block polymer being between 60wt% and 80wt%, and the content of the ethylene polymer being between 20wt% and 40wt%" and "based on the total weight of the auxiliary layer being 100wt%, the content of the propylene block polymer being between 90wt% and 99wt%, and the content of the propylene random copolymer being between 1wt% and 10wt%".

[0020] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the medical easy-tear film of the present invention. Detailed Implementation

[0022] The following specific embodiments illustrate the implementation of the "medical easy-tear film and its manufacturing method" disclosed in this invention. Those skilled in the art can understand the advantages and effects of this invention from the content disclosed in this specification. This invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this invention. Furthermore, the accompanying drawings of this invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated in advance. The following embodiments will further describe the relevant technical content of this invention in detail, but the disclosed content is not intended to limit the scope of protection of this invention.

[0023] It should be understood that while terms such as "first," "second," and "third" may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another, or one signal from another. Furthermore, the term "or" as used herein should, as appropriate, include any combination of one or more of the related listed items.

[0024] See Figure 1 As shown, Figure 1This is a schematic diagram of the medical easy-tear film of the present invention. The present invention provides a medical easy-tear film 100. The medical easy-tear film 100 can be applied to the field of contact lenses. For example, the medical easy-tear film 100 can be used as an easy-tear film for contact lens solutions, such as contact lens preservation solutions. However, the present invention does not limit the application field of the medical easy-tear film 100.

[0025] The medical easy-tear film 100 exhibits a heat-sealing strength between 5 N / 15 mm and 15 N / 15 mm after being subjected to high-temperature sterilization for 30 minutes. Preferably, the heat-sealing strength is between 8 N / 15 mm and 12 N / 15 mm. More preferably, the heat-sealing strength is between 10 N / 15 mm and 12 N / 15 mm. Therefore, the medical easy-tear film 100 retains a specific heat-sealing strength even after high-temperature sterilization.

[0026] It is worth mentioning that the heat-sealing strength of the medical easy-tear film 100 needs to be within a specific range. If the heat-sealing strength of the medical easy-tear film 100 is lower than the lower limit (e.g., lower than 5N / 15mm), the medical easy-tear film 100 will be too easy to loosen. If the heat-sealing strength of the medical easy-tear film 100 is higher than the upper limit (e.g., lower than 15N / 15mm), the medical easy-tear film 100 will not be easily torn by the user.

[0027] The medical easy-tear film 100 includes a release layer 1 and an auxiliary layer 2. In this embodiment, the medical easy-tear film 100 may be formed into a double-layer structure by co-extrusion. The thickness of the medical easy-tear film 100 is between 35 micrometers and 50 micrometers, the thickness of the release layer 1 is between 10.5 micrometers and 15 micrometers, and the thickness of the auxiliary layer 2 is between 21 micrometers and 35 micrometers. Preferably, the thickness of the auxiliary layer 2 is between 24.5 micrometers and 35 micrometers. Alternatively, the thickness of the release layer 1 accounts for 20% to 40% of the thickness of the medical easy-tear film 100, and the thickness of the auxiliary layer 2 accounts for 40% to 80% of the thickness of the medical easy-tear film 100.

[0028] The release layer 1 comprises a propylene block polymer and an ethylene polymer. Based on a total weight of 100 wt% for the release layer 1, the content of the propylene block polymer is between 60 wt% and 80 wt%, and the content of the ethylene polymer is between 20 wt% and 40 wt%. An island structure is formed in the release layer 1, comprising a marine phase and an island phase, wherein the propylene block polymer is defined as the marine phase, and the ethylene polymer is defined as the island phase. The ethylene polymer is selected from at least one of the materials group consisting of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE).

[0029] It should be noted that in the release layer 1, the propylene block polymer is mainly used to impart specific heat resistance to the release layer 1, and the ethylene polymer is mainly used to adjust the heat-sealing strength of the medical easy-tear film 100. Furthermore, if the content of the propylene block polymer in the release layer 1 is too low, the heat resistance of the release layer 1 will be poor. If the content of the ethylene polymer is too low, the heat-sealing strength of the medical easy-tear film 100 will be too high, making it difficult for the user to tear the medical easy-tear film 100. If the content of the ethylene polymer is too high, the heat-sealing strength of the medical easy-tear film 100 will be too low, creating a risk that the medical easy-tear film 100 may loosen at any time. In addition, it is worth mentioning that if the release layer 1 does not contain the ethylene polymer, the heat-sealing strength of the medical easy-tear film 100 is approximately between 60 N / 15 mm and 70 N / 15 mm.

[0030] In the release layer 1, the propylene block polymer comprises propylene monomers and an ethylene-propylene polymer. Based on a total weight of 100 wt% for the propylene block polymer, the content of the propylene monomer is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymer is between 15 wt% and 25 wt%. Preferably, based on a total weight of 100 wt% for the propylene block polymer, the content of the propylene monomer is between 78 wt% and 82 wt%, and the content of the ethylene-propylene polymer is between 18 wt% and 22 wt%. Preferably, the content of the propylene monomer is 82 wt%, and the content of the ethylene-propylene polymer is 18 wt%. Because the propylene block polymer contains an ethylene-propylene polymer, the compatibility between the propylene block polymer and the ethylene polymer, as well as the flexibility of the release layer 1, can be effectively improved.

[0031] In the stripping layer 1, the ethylene-propylene polymer may be dispersed in the propylene monomer to form an island structure, the island structure comprising a marine phase and an island phase, the propylene monomer being defined as the marine phase, and the ethylene-propylene polymer being defined as the island phase.

[0032] In the ethylene-propylene polymer of the propylene block polymer in the release layer 1, the content ratio of ethylene to propylene is 10-45:55-90, preferably 30:70. The limiting viscosity of the ethylene-propylene polymer is 1-5 dl / g, preferably 3 dl / g. The polymerization method for forming the island structure in the propylene block polymer is as follows: first, propylene is polymerized alone, and then ethylene and propylene are batch polymerized. Because the ethylene and propylene copolymer in the later stage and the polymer of pure propylene polymerization will produce incompatible interfaces, the island structure is generated.

[0033] The auxiliary layer 2 comprises a propylene block polymer and a propylene random copolymer. Based on a total weight of 100 wt% for the auxiliary layer 2, the content of the propylene block polymer is between 90 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 10 wt%. Preferably, based on a total weight of 100 wt% for the auxiliary layer, the content of the propylene block polymer is between 95 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 5 wt%.

[0034] In the auxiliary layer 2, the propylene block polymer is mainly used to impart specific heat resistance and flexibility to the auxiliary layer 2, and the propylene random copolymer is mainly used to increase the strength between the auxiliary layer 2 and the release layer 1. In other words, if the content of the propylene block polymer in the auxiliary layer 2 is too low, the auxiliary layer 2 will have poor heat resistance and poor flexibility; if the content of the propylene random copolymer is too low, the strength between the auxiliary layer 2 and the release layer 1 will be insufficient.

[0035] In the auxiliary layer 2, the propylene block polymer comprises propylene monomer and ethylene-propylene polymer. Based on a total weight of 100 wt% for the propylene block polymer, the content of the propylene monomer is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymer is between 15 wt% and 25 wt%. Preferably, based on a total weight of 100 wt% for the propylene block polymer, the content of the propylene monomer is between 78 wt% and 82 wt%, and the content of the ethylene-propylene polymer is between 18 wt% and 22 wt%. It is worth noting that the propylene block polymer in the auxiliary layer 2 may be the same as or different from the propylene block polymer in the release layer 1, and the present invention is not limited thereto.

[0036] The propylene random copolymer is formed by polymerizing propylene monomers and ethylene monomers, and based on a total weight of 100 wt% for the propylene random copolymer, the content of the propylene monomer is between 98 wt% and 99.99 wt%, and the content of the ethylene monomer is between 0.01 wt% and 2 wt%. Preferably, based on a total weight of 100 wt% for the propylene random copolymer, the content of the propylene monomer is between 98 wt% and 99 wt%, and the content of the ethylene monomer is between 1 wt% and 2 wt%.

[0037] [Manufacturing method of medical easy-tear film]

[0038] The present invention also provides a method for manufacturing a medical easy-tear film. The aforementioned medical easy-tear film 100 may be formed by the method described above, but the present invention is not limited thereto. The method for manufacturing the medical easy-tear film includes a preparation step and a co-extrusion step.

[0039] In the preparation step, a propylene block polymer, an ethylene polymer, and a propylene random copolymer are prepared. The propylene block polymer comprises propylene monomers and an ethylene-propylene polymer, wherein the ethylene-propylene polymer is dispersed within the propylene monomers to form a sea-island structure. The sea-island structure comprises a marine phase and an island phase, wherein the propylene monomers are defined as the marine phase, and the ethylene-propylene polymer is defined as the island phase. Preferably, based on a total weight of 100 wt% for the propylene block polymer, the content of the propylene monomers is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymer is between 15 wt% and 25 wt%.

[0040] Furthermore, in this embodiment, the ethylene polymer is selected from at least one of the materials group consisting of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE). The propylene random copolymer is formed by polymerizing propylene monomers and ethylene monomers, and based on a total weight of 100 wt% for the propylene random copolymer, the content of the propylene monomers is between 98 wt% and 99.99 wt%, and the content of the ethylene monomers is between 0.01 wt% and 2 wt%.

[0041] In the co-extrusion step, the propylene block polymer, ethylene polymer, and propylene random copolymer are co-extruded to form a medical easy-tear film 100. The medical easy-tear film includes a release layer 1 and an auxiliary layer 2. The release layer 1 includes the propylene block polymer and the ethylene polymer. Based on the total weight of the release layer 1 being 100 wt%, the content of the propylene block polymer is between 60 wt% and 80 wt%, and the content of the ethylene polymer is between 20 wt% and 40 wt%. In this embodiment, the thickness of the release layer 1 accounts for 20% to 40% of the thickness of the medical easy-tear film 100, and the thickness of the auxiliary layer 2 accounts for 40% to 80% of the thickness of the medical easy-tear film 100, but the present invention is not limited thereto.

[0042] The auxiliary layer 2 comprises the propylene block polymer and the propylene random copolymer. Based on a total weight of 100 wt% for the auxiliary layer 2, the content of the propylene block polymer is between 90 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 10 wt%. Preferably, based on a total weight of 100 wt% for the auxiliary layer 2, the content of the propylene block polymer is between 95 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 5 wt%. Accordingly, the medical easy-tear film 100 has a heat-sealing strength of 5 N / 15 mm to 15 N / 15 mm after 30 minutes at 135°C.

[0043] [Experimental Data Testing]

[0044] The present invention will now be described in detail with reference to Examples 1 to 5 and Comparative Examples 1 to 3. However, the following examples are provided only to help understand the present invention, and the scope of the present invention is not limited to these examples.

[0045] Example 1: The release layer is composed of 80% propylene block polymer and 20% ethylene polymer, accounting for 30% of the overall thickness. The auxiliary layer is composed of 99% propylene block polymer and 1% propylene random copolymer, accounting for 70% of the overall thickness. The three layers are co-extruded into a 35µm film.

[0046] Example 2: The release layer is composed of 70% propylene block polymer and 30% ethylene polymer, accounting for 30% of the overall thickness. The auxiliary layer is composed of 99% propylene block polymer and 1% propylene random copolymer, accounting for 70% of the overall thickness. The three layers are co-extruded into a 35µm film.

[0047] Example 3: The release layer is composed of 60% propylene block polymer and 40% ethylene polymer, accounting for 30% of the overall thickness. The auxiliary layer is composed of 95% propylene block polymer and 5% propylene random copolymer, accounting for 70% of the overall thickness. The three layers are co-extruded into a 35µm film.

[0048] Example 4: The release layer is composed of 70% propylene block polymer and 30% ethylene polymer, accounting for 40% of the total thickness. The auxiliary layer is composed of 99% propylene block polymer and 1% propylene random copolymer, accounting for 60% of the total thickness. The three layers are co-extruded into a 35µm film.

[0049] Example 5: The release layer is composed of 70% propylene block polymer and 30% ethylene polymer, accounting for 30% of the total thickness. The auxiliary layer is composed of 98% propylene block polymer and 2% propylene random copolymer, accounting for 70% of the total thickness. The three layers are co-extruded into a 50µm film.

[0050] Comparative Example 1: The release layer is 100% propylene block polymer, accounting for 30% of the total thickness, and the auxiliary layer is 99% propylene block polymer and 1% propylene random copolymer, accounting for 70% of the total thickness. The three layers are co-extruded into a 35µm film.

[0051] Comparative Example 2: The release layer is 100% ethylene polymer, accounting for 30% of the total thickness, and the auxiliary layer is 99% propylene block polymer and 1% propylene random copolymer, accounting for 70% of the total thickness. The three layers are co-extruded into a 35µm film.

[0052] Comparative Example 3: The release layer is composed of 70% propylene block polymer and 30% ethylene polymer, accounting for 30% of the total thickness. The auxiliary layer is composed of 100% propylene block polymer, accounting for 70% of the total thickness. The three layers are co-extruded into a 35 μm film.

[0053] The component ratios, heat-sealing strengths, and boiling test results of the medical easy-tear films described in Examples 1 to 5 and Comparative Examples 1 to 3 are shown in Table 1 below, and the relevant test methods are explained below.

[0054] Heat seal strength test: The material was bonded to a PP board with a pressure of 3.0 kg, a time of 1 second, a lower plate temperature of 115℃, and an upper plate temperature of 170~190℃. After a 30-minute boiling test at 135℃, the peel strength was analyzed at a speed of 00 mm / min.

[0055] 135℃*30-minute boiling test: with a pressure of 3.0Kg, a time of 1 second, a lower plate temperature of 115℃, and an upper plate temperature of 190℃, the film is bonded to a PP board and placed in a sterilization autoclave for boiling test to confirm the appearance of the film and whether it is properly bonded to the PP board. Normal is indicated by ○, and abnormal is indicated by X.

[0056] [Table 1. Component proportions and physicochemical property test results for the exemplary and comparative examples]

[0057]

[0058]

[0059] In Examples 1-3, after adding 20-40% ethylene polymer to the peeling layer and cooking at 135°C for 30 minutes, the appearance was normal and there was no peeling or delamination, and the peeling strength was optimal.

[0060] Compared with Exemplary Example 2 and Comparative Example 1, if no ethylene polymer is added, although the appearance is normal after cooking at 135°C for 30 minutes, the peel strength is too high, making the film difficult to peel off and tearing.

[0061] Compared with Exemplary Example 2 and Comparative Example 2, when only ethylene polymer was added, the film deformed and peeled off from the PP board after being heated to 135°C for 30 minutes due to insufficient heat resistance, and its strength could not be tested.

[0062] Compared with Exemplary Example 2 and Comparative Example 3, no olefin random copolymer was added to the auxiliary layer to enhance the strength of the release layer, resulting in a release strength of less than 8N, which is too low.

[0063] As can be seen from Examples 1 to 5, the medical easy-tear film described in this case has a heat-sealing strength between 9.2 N / 15 mm and 11.9 N / 15 mm.

[0064] [Beneficial Effects of the Examples]

[0065] One of the beneficial effects of the present invention is that the medical easy-tear film provided by the present invention can improve the problem that existing easy-tear films cannot be applied to products that need to undergo high-temperature sterilization by means of the technical solutions of "based on the total weight of the peeling layer being 100wt%, the content of the propylene block polymer being between 60wt% and 80wt%, and the content of the ethylene polymer being between 20wt% and 40wt%" and "based on the total weight of the auxiliary layer being 100wt%, the content of the propylene block polymer being between 90wt% and 99wt%, and the content of the propylene random copolymer being between 1wt% and 10wt%".

[0066] Furthermore, the medical easy-tear film has a heat-sealing strength between 8N / 15mm and 12N / 15mm after 30 minutes at 135°C, and the medical easy-tear film is a solution-based easy-tear film for contact lenses.

[0067] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made based on the content of the present invention specification and drawings are included in the scope of the patent application of the present invention.

Claims

1. A medical easy-tear film, characterized in that, The medical easy-tear film includes: A release layer comprising a propylene block polymer and an ethylene polymer; wherein, based on a total weight of 100 wt% of the release layer, the content of the propylene block polymer is between 60 wt% and 80 wt%, and the content of the ethylene polymer is between 20 wt% and 40 wt%; wherein, in the release layer, the propylene block polymer comprises propylene monomers and an ethylene-propylene polymer, based on a total weight of 100 wt% of the propylene block polymer, the content of the propylene monomers is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymer is between 15 wt% and 25 wt%; wherein, in the propylene block polymer, the ethylene-propylene polymer is dispersed in the propylene monomers to form an island structure; wherein the island structure comprises a marine phase and an island phase, the propylene monomers are defined as the marine phase, and the ethylene-propylene polymers are defined as the island phase; and An auxiliary layer comprising a propylene block polymer and a propylene random copolymer; wherein, based on a total weight of 100 wt% for the auxiliary layer, the content of the propylene block polymer is between 98 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 2 wt%. The medical easy-tear film has a heat-sealing strength between 5 N / 15 mm and 15 N / 15 mm after being subjected to heat at 135°C for 30 minutes.

2. The medical easy-tear film according to claim 1, characterized in that, An island structure is formed in the stripping layer, the island structure comprising a marine phase and an island phase, the propylene block polymer being defined as the marine phase, and the ethylene polymer being defined as the island phase.

3. The medical easy-tear film according to claim 1, characterized in that, The ethylene polymer is selected from at least one of the group of materials consisting of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE).

4. The medical easy-tear film according to claim 1, characterized in that, In the auxiliary layer, the propylene block polymer comprises propylene monomer and ethylene-propylene polymer, wherein the total weight of the propylene block polymer is 100 wt%, the content of the propylene monomer is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymer is between 15 wt% and 25 wt%.

5. The medical easy-tear film according to claim 1, characterized in that, The propylene random copolymer is formed by polymerization of propylene monomer and ethylene monomer, and based on a total weight of 100 wt% for the propylene random copolymer, the content of the propylene monomer is between 98 wt% and 99.99 wt%, and the content of the ethylene monomer is between 0.01 wt% and 2 wt%.

6. The medical easy-tear film according to claim 1, characterized in that, The thickness of the peeling layer is 20% to 40% of the thickness of the medical easy-tear film, and the thickness of the auxiliary layer is 40% to 80% of the thickness of the medical easy-tear film.

7. The medical easy-tear film according to claim 1, characterized in that, The medical easy-tear film has a heat-sealing strength between 8 N / 15 mm and 12 N / 15 mm after 30 minutes at 135°C; wherein, the medical easy-tear film is a solution-based easy-tear film for contact lenses.

8. A method for manufacturing a medical easy-tear film, characterized in that, The method for manufacturing the medical easy-tear film includes: Preparation step 1: Prepare propylene block polymer, ethylene polymer and propylene random copolymer; wherein, the propylene block polymer comprises propylene monomer and ethylene-propylene polymer, the ethylene-propylene polymer is dispersed in the propylene monomer to form a sea-island structure, the sea-island structure comprises a marine phase and an island phase, the propylene monomer is defined as the marine phase, and the ethylene-propylene polymer is defined as the island phase; A co-extrusion step: The propylene block polymer, ethylene polymer, and propylene random copolymer are co-extruded to form a medical easy-tear film, the medical easy-tear film comprising a release layer and an auxiliary layer; wherein, the release layer comprises the propylene block polymer and the ethylene polymer, based on a total weight of 100 wt%, the content of the propylene block polymer is between 60 wt% and 80 wt%, and the content of the ethylene polymer is between 20 wt% and 40 wt%; wherein, the auxiliary layer comprises the propylene block polymer and the propylene random copolymer, based on a total weight of 100 wt%, the content of the propylene block polymer is between 98 wt% and 99 wt%, and the content of the propylene random copolymer is between 1 wt% and 2 wt%; The medical easy-tear film has a heat-sealing strength between 5 N / 15 mm and 15 N / 15 mm after being subjected to heat at 135°C for 30 minutes.

9. The method for manufacturing the medical easy-tear film according to claim 8, characterized in that, An island structure is formed in the stripping layer, the island structure comprising a marine phase and an island phase, the propylene block polymer being defined as the marine phase, and the ethylene polymer being defined as the island phase.

10. The method for manufacturing the medical easy-tear film according to claim 8, characterized in that, In the preparation step, based on the total weight of the propylene block polymer being 100 wt%, the content of the propylene monomer is between 75 wt% and 85 wt%, and the content of the ethylene-propylene polymer is between 15 wt% and 25 wt%.

11. The method for manufacturing the medical easy-tear film according to claim 8, characterized in that, In the preparation step, the ethylene polymer is selected from at least one of the materials group consisting of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE).

12. The method for manufacturing the medical easy-tear film according to claim 8, characterized in that, In the preparation step, the propylene random copolymer is formed by polymerization of propylene monomer and ethylene monomer, and based on the total weight of the propylene random copolymer being 100 wt%, the content of the propylene monomer is between 98 wt% and 99.99 wt%, and the content of the ethylene monomer is between 0.01 wt% and 2 wt%.

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