An easy peel film, its preparation method and use in medical reagent tubes

Abstract

The present application relates to the technical field of composite film, and provides an easy-to-peel film, a preparation method thereof and application in medical reagent tubes.The easy-to-peel film comprises an outer layer, a middle layer and an inner layer, the preparation raw materials of the outer layer comprise low-density polyethylene and linear low-density polyethylene, the preparation raw materials of the middle layer comprise low-density polyethylene, linear low-density polyethylene and metallocene medium-density polyethylene, and the preparation raw materials of the inner layer comprise low-density polyethylene, metallocene polyethylene and POE elastomer.The present application adds metallocene medium-density polyethylene to the middle layer of the easy-to-peel film, so that the heat sealing strength of the film can be adjusted, and the phenomenon of being sealed dead due to too high heat sealing strength can be avoided;POE elastomer is added to the inner layer, so that the easy-to-peel property of the film can be improved, and the phenomenon of being pulled into a filament or being layered when being peeled off can be avoided.In conclusion, the easy-to-peel film provided by the present application can effectively seal the medical reagent tube, and is not easy to be pulled into a filament or layered when being peeled off, so that the easy-to-peel film has a wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite film, in particular to an easy-to-uncover film, a preparation method thereof and application thereof in medical reagent tubes. BACKGROUND

[0002] The medical reagent tube is a kind of container widely used in medical and laboratory environment, mainly used for containing various medical reagents and biological samples. The cover film of the medical reagent tube can seal the reagent tube, prevent the volatilization and leakage of the reagent, and prevent the entry of external air, moisture and dust into the reagent to cause pollution, thereby protecting the stability of the reagent.

[0003] However, when the current medical reagent tube cover film seals the reagent tube, the sealing strength is large, the cover film and the reagent tube are tightly combined, and it is not easy to uncover when used. If the heat sealing strength is reduced, the cover film and the reagent tube are easily adhered, and when uncovered, the phenomena of pulling thread and layering easily occur, and residues exist on the reagent tube, which easily pollute the reagent when used. SUMMARY

[0004] Therefore, the present application provides an easy-to-uncover film, a preparation method thereof and application thereof in medical reagent tubes. The easy-to-uncover film provided by the present application can effectively seal the medical reagent tube, has moderate heat sealing strength, is easy to uncover, and does not have the phenomena of pulling thread and layering when uncovered, and does not have residues on the reagent tube.

[0005] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0006] An easy-to-uncover film, comprising an outer layer, a middle layer and an inner layer;

[0007] The preparation raw materials of the outer layer include, in mass parts, 10-40 parts of low-density polyethylene and 30-80 parts of linear low-density polyethylene;

[0008] The preparation raw materials of the middle layer include, in mass parts, 10-40 parts of low-density polyethylene, 20-60 parts of linear low-density polyethylene and 30-80 parts of metallocene medium-density polyethylene;

[0009] The preparation raw materials of the inner layer include, in mass parts, 20-80 parts of low-density polyethylene, 20-80 parts of metallocene polyethylene and 10-30 parts of POE elastomer.

[0010] Preferably, the melt index of the low-density polyethylene used in the outer layer and the middle layer is independently 1.5-2.5 g / 10 min, and the density is independently 0.92-0.93 g / cm 3; the linear low density polyethylene used in the outer layer and the middle layer has a melt index of 1.5-2.5 g / 10 min and a density of 0.915-0.925 g / cm 3 .

[0011] Preferably, the metallocene medium density polyethylene used in the middle layer has a melt index of 0.2-1 g / 10 min and a density of 0.93-0.94 g / cm 3 .

[0012] Preferably, the low density polyethylene used in the inner layer has a melt index of 1.5-2.5 g / 10 min and a density of 0.92-0.93 g / cm 3 ; the metallocene polyethylene used in the inner layer has a melt index of 1.5-2.5 g / 10 min and a density of 0.915-0.925 g / cm 3 ; the POE elastomer used in the inner layer has a melt index of 0.5-1.5 g / 10 min.

[0013] Preferably, the low density polyethylene used in the outer layer and the middle layer has a brand of 2420H; the linear low density polyethylene used in the outer layer and the middle layer has a brand of 201XV; and the metallocene medium density polyethylene used in the middle layer has a brand of 3505MC.

[0014] Preferably, the low density polyethylene used in the inner layer has a brand of 2426H; the metallocene polyethylene used in the inner layer has a brand of 2018MB; and the POE elastomer used in the inner layer has a brand of BL3110M.

[0015] The application further provides a preparation method of the easy-to-unfold film.

[0016] Preferably, the three-layer co-extrusion comprises: feeding the preparation raw materials of the outer layer, the middle layer and the inner layer into the outer layer, the middle layer and the inner layer extruders respectively for melt plasticization, conveying the obtained glue solution to a die head, extruding and blowing a film bubble, air cooling the film bubble, and then stably rotating the film bubble through a stabilizing ring and a herringbone arrangement, flattening the film bubble, and then detecting, trimming, removing static electricity and winding the film bubble to obtain the easy-to-unfold film.

[0017] Preferably, the outer layer extruder, the middle layer extruder and the inner layer extruder are each provided with 5 heating zones, which are sequentially recorded as zone 1-5 according to the passing order of raw materials; the temperature of zone 1 of the outer layer extruder is 150-160℃, the temperature of zone 2 is 155-165℃, the temperature of zone 3 is 155-165℃, the temperature of zone 4 is 155-165℃, and the temperature of zone 5 is 155-165℃; the temperature of zone 1 of the middle layer extruder is 150-160℃, the temperature of zone 2 is 160-170℃, the temperature of zone 3 is 160-170℃, the temperature of zone 4 is 160-170℃, and the temperature of zone 5 is 160-170℃; the temperature of zone 1 of the inner layer extruder is 160-170℃, the temperature of zone 2 is 170-180℃, the temperature of zone 3 is 170-180℃, the temperature of zone 4 is 170-180℃, and the temperature of zone 5 is 170-180℃.

[0018] The die head is provided with 4 heating zones, which are sequentially recorded as zone 1-4 according to the passing order of raw materials; the temperature of zone 1 of the die head is 170-180℃, the temperature of zone 2 is 170-180℃, the temperature of zone 3 is 170-180℃, and the temperature of zone 4 is 170-180℃.

[0019] The application further provides application of the easy-to-open film prepared by the preparation method to medical reagent tubes.

[0020] The application provides an easy-to-open film, which comprises an outer layer, a middle layer and an inner layer; the preparation raw materials of the outer layer comprise 10-40 parts of low-density polyethylene and 30-80 parts of linear low-density polyethylene in terms of mass fraction; the preparation raw materials of the middle layer comprise 10-40 parts of low-density polyethylene, 20-60 parts of linear low-density polyethylene and 30-80 parts of metallocene medium-density polyethylene in terms of mass fraction; and the preparation raw materials of the inner layer comprise 20-80 parts of low-density polyethylene, 20-80 parts of metallocene polyethylene and 10-30 parts of POE elastomer in terms of mass fraction. The metallocene medium-density polyethylene is added to the middle layer of the easy-to-open film, so that the heat sealing strength of the film can be adjusted, and the phenomenon of sealing dead due to excessively high heat sealing strength can be avoided; meanwhile, the POE elastomer is added to the inner layer, so that the easy-to-open property of the film can be improved, and the phenomenon of stringing and layering during opening can be avoided. Therefore, the easy-to-open film provided by the application can effectively seal the medical reagent tube, has moderate heat sealing strength, is easy to open, is not prone to stringing and layering during opening, and cannot cause residue on the opening of the reagent tube, so the application has a wide application prospect. DETAILED DESCRIPTION

[0021] The application provides an easy-to-open film, which comprises an outer layer, a middle layer and an inner layer;

[0022] The preparation raw materials of the outer layer include 10-40 parts of low density polyethylene and 30-80 parts of linear low density polyethylene by mass fraction;

[0023] The preparation raw materials of the middle layer include 10-40 parts of low density polyethylene, 20-60 parts of linear low density polyethylene and 30-80 parts of metallocene medium density polyethylene by mass fraction;

[0024] The preparation raw materials of the inner layer include 20-80 parts of low density polyethylene, 20-80 parts of metallocene polyethylene and 10-30 parts of POE elastomer by mass fraction.

[0025] The raw materials used in the application are preferably commercially available products.

[0026] The preparation raw materials of the outer layer include 10-40 parts of low density polyethylene by mass fraction, and specifically can be 10 parts, 20 parts, 25 parts or 30 parts; the melt index of the low density polyethylene used in the outer layer is preferably 1.5-2.5 g / 10 min, and more preferably 2-2.5 g / 10 min, and the density is preferably 0.92-0.93 g / cm 3 , and more preferably 0.924-0.925 g / cm 3 ; in a specific embodiment of the application, the grade of the low density polyethylene used in the outer layer is 2420H, the manufacturer is CNOOC Shell, the melt index is 2 g / 10 min, and the density is 0.924 g / cm 3 . The low density polyethylene used in the application has the characteristics of high cleanliness, good die cutting and easy processing.

[0027] The preparation raw materials of the outer layer include 30-80 parts of linear low density polyethylene by mass fraction of the low density polyethylene used in the outer layer, and specifically can be 70 parts, 75 parts or 80 parts; the melt index of the linear low density polyethylene is preferably 1.5-2.5 g / 10 min, and more preferably 2 g / 10 min, and the density is preferably 0.915-0.925 g / cm 3 , and more preferably 0.915-0.918 g / cm 3 ; in a specific embodiment of the application, the grade of the linear low density polyethylene is 201XV, the manufacturer is Exxon, the melt index is 2 g / 10 min, and the density is 0.918 g / cm 3 . The linear low density polyethylene used in the application has good compatibility and good processability.

[0028] The preparation raw material of the middle layer includes 10-40 parts of low density polyethylene in mass fraction, and specifically can be 10 parts, 20 parts or 30 parts; the melt index, density and grade of the low density polyethylene used in the middle layer are consistent with those of the low density polyethylene used in the outer layer, which will not be repeated here.

[0029] The preparation raw material of the middle layer includes 20-60 parts of linear low density polyethylene in mass fraction of the low density polyethylene used in the middle layer, and specifically can be 30 parts, 40 parts or 50 parts; the melt index, density and grade of the linear low density polyethylene used in the middle layer are consistent with those of the linear low density polyethylene used in the outer layer, which will not be repeated here.

[0030] The preparation raw material of the middle layer includes 30-80 parts of metallocene medium density polyethylene in mass fraction of the low density polyethylene used in the middle layer, and specifically can be 40 parts, 50 parts or 60 parts; the metallocene medium density polyethylene is preferably ethylene 1-hexene copolymer; the melt index of the metallocene medium density polyethylene is preferably 0.2-1 g / 10 min, and more preferably 0.5-1 g / 10 min, and the density is preferably 0.93-0.94 g / cm 3 , and more preferably 0.935-0.94 g / cm 3 ; in the specific embodiment of the present application, the grade of the metallocene medium density polyethylene is 3505MC, which is ethylene 1-hexene copolymer, produced by Exxon, and the melt index is 0.5 g / 10 min and the density is 0.935 g / cm 3 The metallocene medium density polyethylene used in the present application has good adhesion and stiffness.

[0031] The preparation raw material of the inner layer includes 20-80 parts of low density polyethylene in mass fraction, and specifically can be 30 parts, 40 parts, 50 parts or 60 parts; the melt index of the low density polyethylene used in the inner layer is preferably 1.5-2.5 g / 10 min, and more preferably 2-2.5 g / 10 min, and the density is preferably 0.92-0.93 g / cm 3 ; in the specific embodiment of the present application, the grade of the low density polyethylene used in the inner layer is 2426H, produced by CNOOC Shell, and the melt index is 2 g / 10 min and the density is 0.924 g / cm 3 The low density polyethylene used in the inner layer of the present application has the characteristics of high cleanliness, good die cutting and easy processing.

[0032] The preparation raw material of the inner layer comprises 20-80 parts of metallocene polyethylene, specifically 40 parts, 45 parts, 50 parts or 60 parts, based on the mass fraction of the low-density polyethylene used in the inner layer; the melt index of the metallocene polyethylene used in the inner layer is preferably 1.5-2.5 g / 10 min, and the density is preferably 0.915-0.925 g / cm 3 In specific embodiments of the present application, the metallocene polyethylene used in the inner layer has a brand of 2018MB, a manufacturer of Exxon, a melt index of 2 g / 10 min and a density of 0.918 g / cm 3 The metallocene medium-density polyethylene used in the present application has good compatibility and is easy to process.

[0033] The preparation raw material of the inner layer comprises 10-30 parts of POE elastomer, specifically 10 parts, 15 parts, 20 parts or 30 parts, based on the mass fraction of the low-density polyethylene used in the inner layer; the POE elastomer is specifically a 1-butene-based polymer; the melt index of the POE elastomer is preferably 0.5-1.5 g / 10 min, and more preferably 1 g / 10 min; in specific embodiments of the present application, the POE elastomer has a brand of BL3110M, is a 1-butene-based polymer, a manufacturer of Mitsui Chemical, and a melt index of 1 g / 10 min. The POE elastomer used in the present application has good adhesion and compatibility and is easy to peel.

[0034] In the present application, the mass fraction of the outer layer is preferably 20-40%, more preferably 30%, the mass fraction of the middle layer is preferably 30-60%, more preferably 40%, and the mass fraction of the inner layer is preferably 20-30%, more preferably 30%, based on the total mass of the outer layer, the middle layer and the inner layer being 100%.

[0035] In the present application, the longitudinal tensile strength of the easy-to-peel film is preferably 31-34 MPa, the transverse tensile strength is preferably 32-35 MPa, the longitudinal elongation at break is preferably 720-730%, the transverse elongation at break is preferably 740-750%, the longitudinal heat seal strength is preferably 9.8-11.5 N, and the transverse heat seal strength is preferably 9.5-10.8 N.

[0036] In the present application, the thickness of the easy-to-peel film is preferably 40-60 μm, more preferably 50 μm.

[0037] The present application also provides a preparation method of the easy-to-peel film described in the above-mentioned scheme, comprising the following steps: three-layer co-extrusion of the preparation raw materials of the outer layer, the middle layer and the inner layer to obtain the easy-to-peel film.

[0038] In the present application, the three-layer co-extrusion preferably comprises: feeding the raw materials for preparing the outer layer, the middle layer and the inner layer into the outer layer, middle layer and inner layer extruders respectively for melt plasticization, conveying the obtained glue liquid to a die head, extruding and blowing a film bubble, air cooling the film bubble, and then passing the film bubble through a stabilizing ring and a herringbone arrangement to an upper traction rotation, flattening the film bubble, and then detecting, trimming, removing static electricity and winding to obtain the easy-to-open film.

[0039] In the present application, the outer layer extruder, the middle layer extruder and the inner layer extruder are each provided with 5 heating zones, which are sequentially recorded as Zone 1 to Zone 5 according to the passing order of the raw materials; the temperature of Zone 1 of the outer layer extruder is preferably 150-160℃, more preferably 150℃, the temperature of Zone 2 is preferably 155-165℃, more preferably 160℃, the temperature of Zone 3 is preferably 155-165℃, more preferably 160℃, the temperature of Zone 4 is preferably 155-165℃, more preferably 160℃, and the temperature of Zone 5 is preferably 155-165℃, more preferably 160℃; the temperature of Zone 1 of the middle layer extruder is preferably 150-160℃, more preferably 160℃, the temperature of Zone 2 is preferably 160-170℃, more preferably 170℃, the temperature of Zone 3 is preferably 160-170℃, more preferably 170℃, the temperature of Zone 4 is preferably 160-170℃, more preferably 170℃, and the temperature of Zone 5 is preferably 160-170℃, more preferably 170℃; the temperature of Zone 1 of the inner layer extruder is preferably 160-170℃, more preferably 170℃, the temperature of Zone 2 is preferably 170-180℃, more preferably 180℃, the temperature of Zone 3 is preferably 170-180℃, more preferably 180℃, the temperature of Zone 4 is preferably 170-180℃, more preferably 175℃, and the temperature of Zone 5 is preferably 170-180℃, more preferably 175℃.

[0040] In the present application, the die head is preferably provided with 4 heating zones, which are sequentially recorded as Zone 1 to Zone 4 according to the passing order of the raw materials; the temperature of Zone 1 of the die head is preferably 170-180℃, more preferably 175℃, the temperature of Zone 2 is preferably 170-180℃, more preferably 180℃, the temperature of Zone 3 is preferably 170-180℃, more preferably 180℃, and the temperature of Zone 4 is preferably 170-180℃, more preferably 180℃.

[0041] In the present application, the extrusion pressure of the outer layer extruder is preferably 200-600bar, more preferably 300-320bar, the extrusion pressure of the middle layer extruder is preferably 250-600bar, more preferably 300-350bar, and the extrusion pressure of the inner layer extruder is preferably 250-600bar, more preferably 300-330bar.

[0042] In the present application, the detection is preferably the detection of the appearance and crystal points of the film by a crystal point flaw detector; after the detection is completed, the film is cut, then separated into single pieces by the lower traction clamp roller, enters the static electricity removing device for static electricity removing, and then is wound by the front and rear winding devices, so that the easy-to-peel film of the present application is obtained.

[0043] The present application also provides the application of the easy-to-peel film prepared by the preparation method in medical reagent tubes; in the present application, the easy-to-peel film is specifically used as a cap of the medical reagent tube; when the medical reagent tube is heat sealed by the easy-to-peel film of the present application, the heat sealing conditions preferably include that the heat sealing temperature is 140-180℃, the heat sealing pressure is 300Kpa, the heat sealing time is 1s, and the heat sealing width is 15mm.

[0044] The technical solutions in the present application will be clearly and completely described below with reference to the embodiments in the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0045] Embodiment 1

[0046] An easy-to-peel film is made of three layers of outer layer, middle layer and inner layer by co-extrusion blown film, and the weight percentages of the materials in the three layers are respectively 30% for the outer layer, 40% for the middle layer and 30% for the inner layer; the raw material ratio of each layer is shown in Table 1, and the thickness of the easy-to-peel film is 50μm.

[0047] Table 1 Raw material ratio of embodiment 1

[0048]

[0049] The preparation method of the easy-to-peel film is as follows: the outer layer, middle layer and inner layer raw materials are mixed by the automatic batching system according to the proportion, then sent into the outer layer, middle layer and inner layer extruders, the raw materials of the outer layer, middle layer and inner layer are melt plasticized and then sent into the die head, extruded and blown film, then air-cooled and cooled, then the film after being flattened by the cylinder is cooled by the guide roller, enters the crystal point flaw detector to detect the appearance and crystal points of the film, then cut, separated into single pieces by the lower traction clamp roller, enters the static electricity removing device, and then is wound by the front and rear winding devices, so that the easy-to-peel film is obtained; the temperature and pressure of the extruders and the temperature of the die head are shown in Table 2.

[0050] Table 2 Temperature and pressure of the extruders and temperature of the die head

[0051] temperature zone 1 zone 2 zone 3 zone 4 zone 5 pressure (bar) outer layer 150 160 160 160 160 320 middle layer 160 170 170 170 170 350 inner layer 170 180 180 175 175 330 die 175 180 180 180 / /

[0052] Embodiment 2

[0053] An easy-to-peel film is made by co-extrusion blow film of three layers of an outer layer, a middle layer, and an inner layer, the weight percentages of the materials in the three layers being respectively: 30% for the outer layer, 40% for the middle layer, and 30% for the inner layer, the amounts of the raw materials for the layers being shown in Table 3, and the thickness of the easy-to-peel film being 50 μm.

[0054] Table 3 Raw material proportions for Example 2

[0055]

[0056] The preparation method is the same as in Example 1.

[0057] Example 3

[0058] An easy-to-peel film is made by co-extrusion blow film of three layers of an outer layer, a middle layer, and an inner layer, the weight percentages of the materials in the three layers being respectively: 30% for the outer layer, 40% for the middle layer, and 30% for the inner layer, the amounts of the raw materials for the layers being shown in Table 4, and the thickness of the easy-to-peel film being 50 μm.

[0059] Table 4 Raw material proportions for Example 3

[0060]

[0061]

[0062] The preparation method is the same as in Example 3.

[0063] Comparative Example 1

[0064] An easy-to-peel film is made by co-extrusion blow film of three layers of an outer layer, a middle layer, and an inner layer, the weight percentages of the materials in the three layers being respectively: 30% for the outer layer, 40% for the middle layer, and 30% for the inner layer, the amounts of the raw materials for the layers being shown in Table 5, and the thickness of the easy-to-peel film being 50 μm.

[0065] Table 5 Raw material proportions for Comparative Example 1

[0066]

[0067] The preparation method is the same as in Example 1.

[0068] Comparative Example 2

[0069] An easy-to-peel film is made by co-extrusion blow film of three layers of an outer layer, a middle layer, and an inner layer, the weight percentages of the materials in the three layers being respectively: 30% for the outer layer, 40% for the middle layer, and 30% for the inner layer, the amounts of the raw materials for the layers being shown in Table 6, and the thickness of the easy-to-peel film being 50 μm.

[0070] Table 6 Raw material proportions for Comparative Example 2

[0071]

[0072] The preparation method is the same as in Example 1.

[0073] Performance test:

[0074] The tensile strength, elongation at break, heat sealing strength and easy-peeling performance of the easy-peeling films prepared in Example 1, Example 3, Comparative Example 1 and Comparative Example 3 were tested, and the test results are shown in Table 7. The heat sealing conditions were: heat sealing temperature 160℃, heat sealing pressure 300Kpa, heat sealing time 1s, and heat sealing width 15mm. The judgment method of easy-peeling performance was: the film was sealed with the reagent tube sheet material, and if the seal could be pulled open, it was easy to peel; if it was pulled off, it was dead-sealed and not easy to peel.

[0075] Table 7 Performance test results

[0076]

[0077] According to the test results in Table 7, it can be seen that the easy-peeling film of the present application has good mechanical properties, moderate heat sealing strength, good easy-peeling performance, and does not easily appear to pull out, delamination and other situations when peeled off, and does not cause residue at the reagent tube opening. In Comparative Example 1, the use of the inner layer POE elastomer was omitted, and the obtained polyethylene film had too high heat sealing strength and was not easy to peel off; in Comparative Example 2, the middle layer of metallocene medium density polyethylene was omitted, and the obtained polyethylene film had moderate heat sealing strength, but delamination occurred when peeled off.

[0078] The above is only the preferred embodiment of the present application, and it should be noted that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. An easy-to-peel film characterized by, The outer layer, the middle layer and the inner layer are prepared by using the raw materials of the outer layer, the middle layer and the inner layer respectively. The raw materials of the outer layer include 10-40 parts of low-density polyethylene and 30-80 parts of linear low-density polyethylene by mass fraction. The raw materials of the middle layer include 10-40 parts of low-density polyethylene, 20-60 parts of linear low-density polyethylene and 30-80 parts of metallocene medium-density polyethylene by mass fraction. The raw materials of the inner layer include 20-80 parts of low-density polyethylene, 20-80 parts of metallocene polyethylene and 10-30 parts of POE elastomer by mass fraction. The melt index of the low density polyethylene used in the outer and middle layers is independently 1.5 to 2.5 g / 10 min and the density is independently 0.92 to 0.93 g / cm 3 ; the melt index of the linear low density polyethylene used in the outer and middle layers is 1.5 to 2.5 g / 10 min and the density is 0.915 to 0.925 g / cm 3 ; the melt index of the metallocene medium density polyethylene used in the middle layer is 0.2 to 1 g / 10 min and the density is 0.93 to 0.94 g / cm 3 ; the melt index of the low density polyethylene used in the inner layer is 1.5 to 2.5 g / 10 min and the density is 0.92 to 0.93 g / cm 3 ; the melt index of the metallocene polyethylene used in the inner layer is 1.5 to 2.5 g / 10 min and the density is 0.915 to 0.925 g / cm 3 ; the melt index of the POE elastomer used in the inner layer is 0.5 to 1.5 g / 10 min.

2. The easy open lidding film of claim 1, wherein, The low-density polyethylene used in the outer layer and the middle layer is 2420H, the linear low-density polyethylene used in the outer layer and the middle layer is 201XV, and the metallocene medium-density polyethylene used in the middle layer is 3505MC.

3. The easy open lidding film of claim 1, wherein, The low-density polyethylene used in the inner layer is 2426H, the metallocene polyethylene used in the inner layer is 2018MB, and the POE elastomer used in the inner layer is BL3110M.

4. A method of making the easy open lid of any one of claims 1 to 3, comprising the steps of: The outer layer, the middle layer and the inner layer are prepared by using the raw materials of the outer layer, the middle layer and the inner layer respectively.

5. The preparation method according to claim 4, characterized in that, The outer layer, the middle layer and the inner layer are prepared by using the raw materials of the outer layer, the middle layer and the inner layer respectively.

6. The preparation method according to claim 5, characterized in that, The outer layer extruder, the middle layer extruder and the inner layer extruder are all provided with five heating zones, which are sequentially recorded as zone 1-zone 5 according to the passing order of the raw materials; the temperature of zone 1 of the outer layer extruder is 150-160℃, the temperature of zone 2 is 155-165℃, the temperature of zone 3 is 155-165℃, the temperature of zone 4 is 155-165℃, and the temperature of zone 5 is 155-165℃; the temperature of zone 1 of the middle layer extruder is 150-160℃, the temperature of zone 2 is 160-170℃, the temperature of zone 3 is 160-170℃, the temperature of zone 4 is 160-170℃, and the temperature of zone 5 is 160-170℃; the temperature of zone 1 of the inner layer extruder is 160-170℃, the temperature of zone 2 is 170-180℃, the temperature of zone 3 is 170-180℃, the temperature of zone 4 is 170-180℃, and the temperature of zone 5 is 170-180℃. The die head is provided with four heating zones, which are sequentially recorded as zone 1-zone 4 according to the passing order of the raw materials; the temperature of zone 1 of the die head is 170-180℃, the temperature of zone 2 is 170-180℃, the temperature of zone 3 is 170-180℃, and the temperature of zone 4 is 170-180℃.

7. The use of the easy-to-peel film of any one of claims 1-3 or the easy-to-peel film prepared by the preparation method of any one of claims 4-6 in medical reagent tubes.

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