Expanded polytetrafluoroethylene back adhesive tape material

Abstract

The utility model relates to the technical field of back adhesive tapes, in particular to an expanded polytetrafluoroethylene back adhesive tape. The utility model relates to an expanded polytetrafluoroethylene back adhesive tape which comprises an expanded polytetrafluoroethylene film and an adhesive layer arranged on the expanded polytetrafluoroethylene film, the expanded polytetrafluoroethylene film comprises a first surface and a second surface; the first surface is in contact with the adhesive layer, and the second surface deviates from the adhesive layer; the first surface is a hydrophilic expanded polytetrafluoroethylene membrane surface, and the second surface is a hydrophobic expanded polytetrafluoroethylene membrane surface. According to the expanded polytetrafluoroethylene back adhesive tape material provided by the utility model, the hydrophilic surface of the expanded polytetrafluoroethylene film is contacted with the adhesive layer, so that the bonding effect of the expanded polytetrafluoroethylene film and the adhesive layer is improved, the expanded polytetrafluoroethylene film is not easy to fall off in use, and the service life of the expanded polytetrafluoroethylene back adhesive tape material is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of adhesive tapes, in particular to an expanded polytetrafluoroethylene adhesive tape. Background Art

[0002] Expanded polytetrafluoroethylene (EPTFE) membranes are widely used in the petrochemical, aerospace, electronics, and other fields due to their low surface energy, stable chemical properties, excellent corrosion resistance, environmental resistance, and low density. However, the smooth surface and low surface energy of expanded PTFE membranes make them difficult to bond to other materials, significantly limiting their use as sealing materials.

[0003] Currently, specialized adhesives for expanded PTFE membranes are generally complex to prepare and expensive. Alternatively, adhesives can be used directly to bond expanded PTFE membranes to other materials, but the bonding effect is generally poor and can only be used in applications where the need for adhesives is short-lived. Expanded PTFE membranes undergo corona treatment, where the surface is coated with hot-melt adhesive, achieving adhesion between the adhesive and the expanded membrane. However, this method requires corona treatment equipment and places strict requirements on the size of the expanded PTFE membrane. Furthermore, due to the limited effectiveness of corona treatment, liquid adhesives are generally used for curing bonding. This limited adhesive selection limits its application.

[0004] For the treatment of expanded polytetrafluoroethylene film, corona, plasma and other methods are generally used to increase the surface energy and improve the adhesion. On the one hand, this method is time-sensitive and requires bonding immediately after treatment; on the other hand, the bonding effect after bonding is improved by this treatment method but the effect is not significant, and it will still fall off after long-term use.

[0005] In view of this, the present utility model is proposed. Utility Model Content

[0006] The utility model aims to provide an expanded polytetrafluoroethylene adhesive tape, which increases the bonding effect between the expanded polytetrafluoroethylene film and the adhesive layer, makes it difficult to fall off during use, and has a long service life.

[0007] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are adopted:

[0008] The utility model provides an expanded polytetrafluoroethylene adhesive tape, comprising an expanded polytetrafluoroethylene film and an adhesive layer arranged on the expanded polytetrafluoroethylene film;

[0009] The expanded polytetrafluoroethylene film includes a first surface and a second surface; the first surface is in contact with the adhesive layer, and the second surface is away from the adhesive layer;

[0010] The first surface is a hydrophilic expanded polytetrafluoroethylene membrane surface, and the second surface is a hydrophobic expanded polytetrafluoroethylene membrane surface.

[0011] Furthermore, the expanded polytetrafluoroethylene membrane includes a hydrophilic layer and a hydrophobic layer, and the hydrophilic layer is located between the hydrophobic layer and the adhesive layer.

[0012] Furthermore, the adhesive layer includes a first adhesive layer, an isolation reinforcement layer, and a second adhesive layer stacked in sequence; the first adhesive layer is in contact with the first surface of the expanded polytetrafluoroethylene film.

[0013] Furthermore, an adhesive protective film is provided on the surface of the adhesive layer away from the expanded polytetrafluoroethylene film.

[0014] Furthermore, the water contact angle of the hydrophilic layer is 50° to 80°;

[0015] And / or, the water contact angle of the hydrophobic layer is 120° to 140°.

[0016] Furthermore, the thickness of the expanded polytetrafluoroethylene film is 0.2 to 2.5 mm.

[0017] Furthermore, the thickness of the hydrophilic layer is 100 μm to 2.1 mm;

[0018] And / or, the thickness of the hydrophobic layer is 100 μm to 2.1 mm.

[0019] Furthermore, the thickness of the isolation reinforcement layer is 0.05 to 0.2 mm.

[0020] Furthermore, the thickness of the first adhesive layer and the second adhesive layer are independently 10 to 100 μm.

[0021] Furthermore, the first adhesive layer and the second adhesive layer each independently include a thermosetting adhesive layer or a pressure-sensitive adhesive layer.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] The expanded polytetrafluoroethylene (PTFE) adhesive tape provided by the utility model adopts an expanded polytetrafluoroethylene (PTFE) film with hydrophilicity on one side and hydrophobicity on the other side. The surface of the expanded polytetrafluoroethylene (PTFE) film with hydrophilicity is in contact with the adhesive layer, thereby improving the bonding effect between the expanded polytetrafluoroethylene (PTFE) film and the adhesive layer, making the expanded polytetrafluoroethylene (PTFE) film less likely to fall off during long-term use, thereby increasing the service life of the expanded polytetrafluoroethylene (PTFE) adhesive tape and solving the problem of difficult bonding of the expanded polytetrafluoroethylene (PTFE) adhesive tape. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a schematic structural diagram of the expanded polytetrafluoroethylene adhesive tape of the present invention.

[0026] Reference numerals:

[0027] 1- expanded polytetrafluoroethylene membrane; 11- first surface;

[0028] 12-second surface; 2-adhesive layer;

[0029] 3- Adhesive protective film. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but those skilled in the art will understand that the embodiments described below are part of the embodiments of the present invention, rather than all of the embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0031] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0032] See also Figure 1 The utility model provides an expanded polytetrafluoroethylene adhesive tape, comprising an expanded polytetrafluoroethylene film 1 and an adhesive layer 2 arranged on the expanded polytetrafluoroethylene film 1;

[0033] The expanded polytetrafluoroethylene film 1 includes a first surface 11 and a second surface 12; the first surface 11 is in contact with the adhesive layer 2, and the second surface 12 is away from the adhesive layer 2;

[0034] The first surface 11 is a hydrophilic expanded polytetrafluoroethylene membrane surface, and the second surface 12 is a hydrophobic expanded polytetrafluoroethylene membrane surface.

[0035] In the expanded polytetrafluoroethylene (PTFE) adhesive tape of the present invention, the first surface and the second surface of the expanded polytetrafluoroethylene (PTFE) film are two sides of the same expanded polytetrafluoroethylene (PTFE) film, one side is hydrophilic and the other side is hydrophobic. The hydrophilic surface of the expanded polytetrafluoroethylene (PTFE) film is in contact with the adhesive layer, thereby enhancing the bonding effect between the expanded polytetrafluoroethylene (PTFE) film and the adhesive layer, making it less likely to fall off during long-term use, thereby increasing the service life of the expanded polytetrafluoroethylene (PTFE) adhesive tape, solving the problem of difficult bonding of the expanded polytetrafluoroethylene (PTFE) adhesive tape, and having certain prospects in industrial implementation.

[0036] In some embodiments, the expanded polytetrafluoroethylene membrane 1 includes a hydrophilic layer and a hydrophobic layer, and the hydrophilic layer is located between the hydrophobic layer and the adhesive layer 2 .

[0037] The expanded polytetrafluoroethylene (PTFE) adhesive tape of the present invention has a unique "three-layer" structure, comprising a hydrophobic layer with low surface energy, a hydrophilic layer with high surface energy, and an adhesive layer, which are sequentially arranged. The hydrophobic layer and the hydrophilic layer are two different sides of the same expanded polytetrafluoroethylene (PTFE) membrane. One side of the expanded polytetrafluoroethylene (PTFE) membrane is hydrophilic, enabling better bonding with the adhesive layer. The other side is hydrophobic, maintaining the original hydrophobic, breathable, and antifouling properties of the expanded polytetrafluoroethylene (PTFE) membrane. This improves the bonding performance while allowing the adhesive tape to have the advantages of a hydrophobic membrane after bonding.

[0038] In some embodiments, the adhesive layer 2 comprises a single adhesive layer.

[0039] In some embodiments, the adhesive layer 2 includes a first adhesive layer, an isolation reinforcement layer, and a second adhesive layer stacked in sequence; the first adhesive layer is in contact with the first surface of the expanded polytetrafluoroethylene film.

[0040] By adding an isolation reinforcement layer between the first adhesive layer and the second adhesive layer, compared with a single-layer adhesive layer structure, it can effectively isolate the corrosion of non-polar media and enhance the overall structural stability and sealing performance.

[0041] In some embodiments, an adhesive protective film 3 is provided on the surface of the adhesive layer 2 facing away from the expanded polytetrafluoroethylene film 1. When the adhesive layer 2 is a single adhesive layer, the adhesive protective film 3 is provided on the surface facing away from the expanded polytetrafluoroethylene film 1. When the adhesive layer 2 is a first adhesive layer, an isolation reinforcement layer, and a second adhesive layer stacked in sequence, the adhesive protective film 3 is provided on the surface of the second adhesive layer facing away from the expanded polytetrafluoroethylene film 1.

[0042] In some embodiments, the expanded polytetrafluoroethylene membrane 1 is an expanded polytetrafluoroethylene membrane that has been hydrophilically modified on one side. The preparation method thereof comprises the following steps:

[0043] After an unmodified expanded polytetrafluoroethylene membrane is soaked in a photoinitiator solution, one side is sprayed with an anionic surfactant aqueous solution, and then irradiated with ultraviolet light to obtain a single-sided hydrophilic-modified expanded polytetrafluoroethylene membrane (an expanded polytetrafluoroethylene membrane with hydrophilic / hydrophobic properties); one side of the single-sided hydrophilic-modified expanded polytetrafluoroethylene membrane has hydrophilicity after the hydrophilic modification, while the other side is unmodified and maintains its original hydrophobicity.

[0044] In some embodiments, the photoinitiator in the photoinitiator solution includes at least one of α-ketoglutaric acid, α,α-diethoxyacetophenone, α-hydroxyalkyl phenone and α-aminoalkyl phenone; the solvent of the photoinitiator solution includes at least one of ethanol, acetone and N,N-dimethylformamide; and the concentration of the photoinitiator solution is 0.05 wt% to 5 wt%.

[0045] In some embodiments, the soaking time is 1 to 6 hours.

[0046] In some embodiments, the anionic surfactant in the aqueous anionic surfactant solution includes sodium linear alkylbenzene sulfonate and / or sodium alkylbenzene sulfonate; for example, the anionic surfactant may be at least one of sodium dodecylbenzene sulfonate, sodium lauryl sulfate, and sodium lauryl sulfate.

[0047] In some embodiments, the spraying time is 10 to 1200 seconds.

[0048] In some embodiments, the concentration of the aqueous solution of anionic surfactant is 2 wt % to 7 wt %.

[0049] In some embodiments, the ultraviolet light irradiation time is 30 to 900 seconds.

[0050] In some embodiments, a single layer of adhesive material is coated on the hydrophilically modified surface of a single-sided hydrophilically modified expanded polytetrafluoroethylene membrane, and after curing, an adhesive layer 2 is obtained; an adhesive protective film 3 is placed on the surface of the adhesive layer 2 to obtain an expanded polytetrafluoroethylene backing tape.

[0051] In some embodiments, the material of the first adhesive layer is coated on the hydrophilically modified surface of an expanded polytetrafluoroethylene membrane that has been hydrophilically modified on one side, and after curing, an expanded polytetrafluoroethylene membrane with the first adhesive layer is obtained; the material of the second adhesive layer is coated on the surface of the isolation reinforcement layer, and after curing, an isolation reinforcement layer with the second adhesive layer is obtained; the expanded polytetrafluoroethylene membrane with the first adhesive layer and the isolation reinforcement layer with the second adhesive layer are laminated to obtain an expanded polytetrafluoroethylene backing tape.

[0052] In some embodiments, the adhesive protective film 3 includes a single-sided silicon-coated release film with any one of PE, PET and PFTE as a base material.

[0053] In some embodiments, the expanded polytetrafluoroethylene membrane 1 is any conventional polytetrafluoroethylene membrane in the art, for example, an expanded polytetrafluoroethylene thin film, an expanded polytetrafluoroethylene flat membrane, an expanded polytetrafluoroethylene hollow fiber membrane, and the like.

[0054] In some embodiments, the water contact angle of the hydrophilic layer is 50° to 80°; for example, the water contact angle of the hydrophilic layer can be 50°, 55°, 60°, 65°, 70°, 75°, 80°, or a range of any two thereof. The water contact angle of the hydrophilic layer of the expanded polytetrafluoroethylene membrane 1 is 50° to 80°. A significantly lower water contact angle, i.e., increased surface energy, makes bonding easier.

[0055] In some embodiments, the water contact angle of the hydrophobic layer is 120° to 140°; for example, the water contact angle of the hydrophobic layer of the expanded polytetrafluoroethylene membrane 1 can be 120°, 125°, 130°, 135°, 140° or any range therebetween.

[0056] In some embodiments, the thickness of the expanded polytetrafluoroethylene membrane 1 is 0.2-2.5 mm; for example, the thickness of the expanded polytetrafluoroethylene membrane 1 can be 0.2 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, or any range therebetween.

[0057] In some embodiments, the thickness of the hydrophilic layer is 100 μm to 2.1 mm; for example, the thickness of the hydrophilic layer can be 100 μm, 500 μm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, or any range therebetween.

[0058] In some embodiments, the thickness of the hydrophobic layer is 100 μm to 2.1 mm; for example, the thickness of the hydrophobic layer can be 100 μm, 500 μm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, or any range therebetween.

[0059] In some embodiments, the thickness of a single adhesive layer is 10-100 μm.

[0060] In some embodiments, the isolation reinforcement layer includes a polyimide (PI) film.

[0061] Polyimide film has high chemical stability, heat resistance, solvent resistance and good mechanical strength, which is beneficial to improving the bonding effect, chemical stability, physical and mechanical properties of the adhesive layer and improving environmental adaptability.

[0062] In some embodiments, the thickness of the isolation reinforcement layer is 0.05-0.2 mm; for example, the thickness of the isolation reinforcement layer can be 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, etc.

[0063] In some embodiments, the thickness of the first adhesive layer and the second adhesive layer is independently 10-100 μm; for example, the thickness of the first adhesive layer and the second adhesive layer is independently 10 μm, 30 μm, 50 μm, 80 μm, 100 μm or any range therebetween.

[0064] In some embodiments, the first adhesive layer includes a thermosetting adhesive layer or a pressure-sensitive adhesive layer.

[0065] In some embodiments, the first adhesive layer and the second adhesive layer include thermosetting adhesive layers or pressure-sensitive adhesive layers.

[0066] In some embodiments, the thermosetting adhesive includes a heat-curing adhesive or a room temperature-curing adhesive.

[0067] In some embodiments, the first adhesive layer and the second adhesive layer include acrylic adhesive or organic silicone adhesive.

[0068] Example 1

[0069] The expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes a hydrophobic layer with a thickness of 1 mm and a water contact angle of 125°, a hydrophilic layer with a thickness of 0.5 mm and a water contact angle of 67°, and a thermosetting adhesive layer 2 with a thickness of 50 μm.

[0070] The method for preparing the expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes the following steps:

[0071] An unmodified expanded polytetrafluoroethylene membrane with a thickness of 1.5 mm was immersed in a 1 wt% α-ketoglutaric acid solution (the solvent was ethanol) for 1 hour, and then removed and dried. A 5 wt% aqueous solution of sodium dodecylbenzenesulfonate was sprayed on one side for 20 seconds. The sprayed surface was reacted under ultraviolet light for 15 minutes, and then removed, cleaned, and dried to obtain an expanded polytetrafluoroethylene membrane with hydrophilic / hydrophobic properties.

[0072] A layer of thermosetting adhesive with a thickness of 50 μm is coated on the surface of a hydrophilic expanded polytetrafluoroethylene film, and after curing, an expanded polytetrafluoroethylene adhesive-backed tape is obtained.

[0073] Example 2

[0074] The expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes a hydrophobic layer with a thickness of 1 mm and a water contact angle of 130°, a hydrophilic layer with a thickness of 1 mm and a water contact angle of 70°, and a thermosetting adhesive layer 2 with a thickness of 90 μm.

[0075] The method for preparing the expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes the following steps:

[0076] A 2mm thick unmodified expanded polytetrafluoroethylene membrane was immersed in a 1wt% α-ketoglutaric acid solution (ethanol as the solvent) for 1 hour, removed and dried, and one side was sprayed with a 5wt% sodium dodecylbenzenesulfonate aqueous solution for 20 seconds. The sprayed surface was reacted under ultraviolet light for 15 minutes, removed, cleaned, and dried to obtain an expanded polytetrafluoroethylene membrane with hydrophilic / hydrophobic properties.

[0077] A layer of thermosetting adhesive with a thickness of 90 μm is coated on the surface of a hydrophilic expanded polytetrafluoroethylene film, and after curing, an expanded polytetrafluoroethylene adhesive-backed tape is obtained.

[0078] Example 3

[0079] The expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes a hydrophobic layer with a thickness of 1.5 mm and a water contact angle of 131°, a hydrophilic layer with a thickness of 0.6 mm and a water contact angle of 57°, and a thermosetting adhesive layer 2 with a thickness of 50 μm, which are arranged in sequence.

[0080] The method for preparing the expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes the following steps:

[0081] An unmodified expanded polytetrafluoroethylene membrane with a thickness of 2.1 mm was immersed in a 1 wt% α-ketoglutaric acid solution (the solvent was ethanol) for 1 hour, removed and dried, and a 7 wt% aqueous solution of sodium dodecylbenzenesulfonate was sprayed on one side for 20 seconds. The sprayed surface was reacted under ultraviolet light for 10 minutes, removed, cleaned, and dried to obtain an expanded polytetrafluoroethylene membrane with hydrophilic / hydrophobic properties.

[0082] A layer of thermosetting adhesive with a thickness of 50 μm is coated on the surface of a hydrophilic expanded polytetrafluoroethylene film, and after curing, an expanded polytetrafluoroethylene adhesive-backed tape is obtained.

[0083] Example 4

[0084] The expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes a hydrophobic layer with a thickness of 2 mm and a water contact angle of 127°, a hydrophilic layer with a thickness of 0.5 mm and a water contact angle of 75°, and a thermosetting adhesive layer 2 with a thickness of 65 μm.

[0085] The method for preparing the expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes the following steps:

[0086] An unmodified expanded polytetrafluoroethylene membrane with a thickness of 2.5 mm was immersed in a 1 wt% α-ketoglutaric acid solution (the solvent was ethanol) for 1 hour, and then removed and dried. A 7 wt% aqueous solution of sodium dodecylbenzenesulfonate was sprayed on one side for 15 seconds. The sprayed surface was reacted under ultraviolet light for 5 minutes, and then removed, cleaned, and dried to obtain an expanded polytetrafluoroethylene membrane with hydrophilic / hydrophobic properties.

[0087] A layer of thermosetting adhesive with a thickness of 65 μm is coated on the surface of a hydrophilic expanded polytetrafluoroethylene film, and after curing, an expanded polytetrafluoroethylene adhesive-backed tape is obtained.

[0088] Example 5

[0089] The expanded polytetrafluoroethylene adhesive tape provided in this embodiment refers to the embodiment 1, except that an adhesive protective film 3 is provided on the surface of the thermosetting adhesive layer 2 .

[0090] Example 6

[0091] The expanded polytetrafluoroethylene (PTFE) adhesive tape provided in this embodiment includes: a hydrophobic layer with a thickness of 1 mm and a water contact angle of 125°, a hydrophilic layer with a thickness of 0.5 mm and a water contact angle of 67°, a first adhesive layer with a thickness of 50 μm, a polyimide film with a thickness of 0.1 mm, and a second adhesive layer with a thickness of 50 μm, which are arranged in sequence; the first adhesive layer and the second adhesive layer include acrylic adhesives.

[0092] The method for preparing the expanded polytetrafluoroethylene adhesive tape provided in this embodiment includes the following steps:

[0093] An unmodified expanded polytetrafluoroethylene membrane with a thickness of 1.5 mm was immersed in a 1 wt% α-ketoglutaric acid solution (the solvent was ethanol) for 1 hour, and then removed and dried. A 5 wt% aqueous solution of sodium dodecylbenzenesulfonate was sprayed on one side for 20 seconds. The sprayed surface was reacted under ultraviolet light for 15 minutes, and then removed, cleaned, and dried to obtain an expanded polytetrafluoroethylene membrane with hydrophilic / hydrophobic properties.

[0094] A layer of acrylic adhesive with a thickness of 50 μm is applied on the surface of a hydrophilic expanded polytetrafluoroethylene film, and after curing, an expanded polytetrafluoroethylene film with a first adhesive layer is obtained; the acrylic adhesive is applied to the surface of a polyimide film, and after curing, a polyimide film with a second adhesive layer is obtained; the expanded polytetrafluoroethylene film with the first adhesive layer and the polyimide film with the second adhesive layer are laminated to obtain an expanded polytetrafluoroethylene backing tape.

[0095] Comparative Example 1

[0096] The expanded polytetrafluoroethylene adhesive tape provided in this comparative example includes an unmodified expanded polytetrafluoroethylene film (ie, a hydrophobic layer) with a thickness of 1 mm and a water contact angle of 131° and a thermosetting adhesive layer with a thickness of 60 μm.

[0097] The preparation method of the expanded polytetrafluoroethylene adhesive tape provided in this comparative example comprises the following steps:

[0098] A layer of thermosetting adhesive with a thickness of 60 μm is coated on the surface of an unmodified expanded polytetrafluoroethylene film, and after curing, an expanded polytetrafluoroethylene adhesive-backed tape is obtained.

[0099] Test example

[0100] The properties of the expanded polytetrafluoroethylene adhesive tapes of Examples 1 to 5 of the present invention and Comparative Example 1 were tested, and the results are shown in Table 1.

[0101] The peel force test standard refers to GB / T2792-2014.

[0102] Table 1

[0103]

[0104] Although the present invention has been illustrated and described using specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features therein may be replaced by equivalents, without departing from the spirit and scope of the present invention. However, these modifications or replacements do not deviate from the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. An expanded polytetrafluoroethylene adhesive tape, characterized in that: It comprises an expanded polytetrafluoroethylene film and an adhesive layer provided on the expanded polytetrafluoroethylene film; The expanded polytetrafluoroethylene film includes a first surface and a second surface; the first surface is in contact with the adhesive layer, and the second surface is away from the adhesive layer; The first surface is a hydrophilic expanded polytetrafluoroethylene membrane surface, and the second surface is a hydrophobic expanded polytetrafluoroethylene membrane surface.

2. The expanded polytetrafluoroethylene adhesive tape according to claim 1, characterized in that: The expanded polytetrafluoroethylene membrane includes a hydrophilic layer and a hydrophobic layer, and the hydrophilic layer is located between the hydrophobic layer and the adhesive layer.

3. The expanded polytetrafluoroethylene adhesive tape according to claim 1, characterized in that: The adhesive layer includes a first adhesive layer, an isolation reinforcement layer, and a second adhesive layer stacked in sequence; the first adhesive layer is in contact with the first surface of the expanded polytetrafluoroethylene film.

4. The expanded polytetrafluoroethylene adhesive tape according to claim 1, characterized in that: An adhesive protective film is provided on the surface of the adhesive layer away from the expanded polytetrafluoroethylene film.

5. The expanded polytetrafluoroethylene adhesive tape according to claim 2, characterized in that: The water contact angle of the hydrophilic layer is 50° to 80°; And / or, the water contact angle of the hydrophobic layer is 120° to 140°.

6. The expanded polytetrafluoroethylene adhesive tape according to claim 2, characterized in that: The thickness of the expanded polytetrafluoroethylene film is 0.2 to 2.5 mm.

7. The expanded polytetrafluoroethylene adhesive tape according to claim 2, characterized in that: The thickness of the hydrophilic layer is 100 μm to 2.1 mm; And / or, the thickness of the hydrophobic layer is 100 μm to 2.1 mm.

8. The expanded polytetrafluoroethylene adhesive tape according to claim 3, characterized in that: The thickness of the isolation reinforcement layer is 0.05 to 0.2 mm.

9. The expanded polytetrafluoroethylene adhesive tape according to claim 3, characterized in that: The thickness of the first adhesive layer and the second adhesive layer are each independently 10 to 100 μm.

10. The expanded polytetrafluoroethylene adhesive tape according to claim 3, characterized in that: The first adhesive layer and the second adhesive layer each independently include a thermosetting adhesive layer or a pressure-sensitive adhesive layer.

Images