Novel heat-sealing cover tape and preparation method thereof

Abstract

The invention discloses a novel heat-sealing cover tape and a preparation method thereof, and belongs to the technical field of preparation of layered products for electronic element packaging. The preparation method comprises the following step: processing the high-strength base material layer and the thermoplastic layer with the anti-static function under the lamination pressure of 1MPa. The base material layer of the cover tape is subjected to composite modification to obtain the high-strength base material layer with good tensile strength and bonding strength, then a mixture of butadiene styrene rubber and methyl silicone resin is used as an adhesive base material, titanium dioxide is added and coupled with potassium titanate whiskers, and the high-strength base material layer is obtained. The thermoplastic layer with a continuous anti-static function and thermal stability is prepared, finally, the high-strength base material layer and the thermoplastic layer with the anti-static function form the heat-sealing cover tape through a laminating technology, and the heat-sealing cover tape has good low-temperature heat-sealing and anti-static functions.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation of layered products for electronic component packaging, and in particular relates to a novel heat-sealing cover tape and a preparation method thereof. Background Art

[0002] Cover tape, commonly known as "cover film" or "package cover tape", is an important material used to protect components during the packaging process of electronic components. It is generally made of plastic, metal or other composite materials, and is mainly used to cover and protect electronic components such as chips, sensors and discrete components. Cover tape is mainly used in the electronic component mounting industry. The cover tape can be composed of a single substrate layer, or different functional layers can be coated by strip coating, interval coating or continuous coating to form a cover tape with specific functions. It is then used in conjunction with a carrier tape to carry and store electronic components such as resistors, capacitors, transistors, diodes, etc. in the pockets of the carrier tape. The cover tape is sealed above the pockets formed by the carrier tape to form a closed package to protect the electronic components from contamination and damage during transportation. When the electronic components are mounted, the cover tape is peeled off, and the automatic mounting equipment takes out the components in the pockets one by one through the precise positioning of the index holes of the carrier tape, and mounts them on the integrated circuit board.

[0003] The cover tape is usually divided into two types: pressure-sensitive sealing and heat-sensitive sealing. Pressure-sensitive sealing refers to applying continuous pressure through the pressure roller of the sealing machine so that the pressure-sensitive adhesive on the cover tape adheres to the carrier tape to achieve the wrapping of electronic components. However, this method has high requirements on the compressive resistance of the carrier tape material. If the compressive resistance is low, it is easy to cause the carrier tape to be squeezed and crushed during pressure-sensitive sealing, thereby damaging the electronic components. Heat-sensitive sealing is a more commonly used technical method at present. It uses a sealing machine to apply a certain temperature and pressure to melt the hot melt adhesive of the cover tape and press it on the sealing surface of the carrier tape to achieve sealing. The advantage of this method is that the heat-sensitive tape used for heat-sensitive sealing is not sticky at room temperature and only has stickiness when heated. In addition, the sealing pressure required is small and will not cause damage to the carrier tape. When the cover tape is peeled off, it is easy to accumulate charges due to friction, thereby generating static electricity. These static electricity easily lead to the adsorption of dust and damage to electronic components. Therefore, it is of great value to design a cover tape with anti-static function.

[0004] Patent CN115027115A discloses an environmentally friendly composite cover tape and its preparation process. The invention designs a composite cover tape having a PET layer, a PE layer and a TPE layer, and then composites the raw materials used for the PE layer and the TPE layer, and controls the weight ratio of the ethylene / sodium methacrylate copolymer in the TPE layer raw material, thereby achieving antistatic performance.

[0005] Patent CN103043302A discloses an environmentally friendly composite cover tape and its preparation process. The invention achieves antistatic performance by arranging a first antistatic layer under the substrate film layer. The first antistatic layer is obtained by coating a solution of one or a mixture of metal oxides, conductive carbon black, carbon nanotubes, organic conductive agents and ionic liquids.

[0006] Although the above two patents realize the antistatic function of the cover tape, due to the limitation of the antistatic principle, the antistatic performance of each individual is quite different, and the antistatic performance will weaken over time. At the same time, due to the limited bonding strength of the various layers of the cover tape, friction may occur between the layers of the cover tape when peeling off the cover tape, thereby generating more static electricity.

[0007] Therefore, it is of great significance to develop a device with a continuous and stable anti-static function while reducing the generation of static electricity when peeling off the cover tape. Summary of the invention

[0008] According to the shortcomings of the prior art, the present invention modifies and optimizes the base material layer of the cover tape to obtain a high-strength base material layer with good tensile strength and bonding strength, and then uses a mixture of styrene-butadiene rubber and methyl silicone resin as the adhesive base material, and prepares a thermoplastic layer with continuous antistatic function and thermal stability by adding titanium dioxide and coupling potassium titanate whiskers. Finally, the high-strength base material layer and the thermoplastic layer with antistatic function are formed into a heat-sealed cover tape through lamination technology, which solves the technical problems raised in the background technology. Specifically, the technical solution of the present invention includes the following contents: A novel heat-sealing cover tape, the heat-sealing cover tape is composed of a high-strength base material layer and a thermoplastic layer with antistatic function; The method for preparing the high-strength substrate layer comprises the following steps: mixing epoxy vinyl ester resin, styrene, methyl ethyl ketone peroxide and a polysiloxane-tetraethyl orthosilicate mixture to obtain a substrate layer mixture; The substrate layer mixture is blended at a temperature of 140° C. to 160° C. at a rotation speed of 80 r / min for 15 min to 30 min, and then poured into a mold and cooled naturally to form the high-strength substrate layer.

[0009] Furthermore, the epoxy vinyl ester resin includes MFE-2 high performance epoxy vinyl ester resin or MFE722 high performance epoxy vinyl ester resin.

[0010] Furthermore, the weight ratio of the epoxy vinyl ester resin, styrene, methyl ethyl ketone peroxide and the polysiloxane-tetraethyl orthosilicate mixture is 20:4:0.1:20.

[0011] Furthermore, the polysiloxane-tetraethyl orthosilicate mixture is obtained by mixing polysiloxane, cobalt cyclohexane and tetraethyl orthosilicate in a weight ratio of 1:3:10.

[0012] Furthermore, the method for preparing the thermoplastic layer with antistatic function comprises the following steps: The styrene-butadiene rubber, silicone rubber, methyl silicone resin and titanium dioxide are mixed and ground to obtain a thermoplastic layer mixture; The potassium titanate whisker and dibutyltin dilaurate are mixed to obtain activated potassium titanate whisker; Mixing methyl tributylidene oxime silane and 3-aminopropyl triethoxy silane to obtain a silane mixture; The thermoplastic layer mixture, activated potassium titanate whiskers and silane mixture are mixed to obtain a reaction solution; The reaction solution is heated to 80° C. to 90° C. and reacted for 10 h to 12 h to obtain the thermoplastic layer with antistatic function.

[0013] Furthermore, the styrene-butadiene rubber, silicone rubber, methyl silicone resin and titanium dioxide are mixed in a weight ratio of 10:3:2:1.

[0014] Furthermore, the particle size of particles in the thermoplastic layer mixture is less than 50 μm.

[0015] Furthermore, the potassium titanate whisker and dibutyltin dilaurate are in a weight ratio of 10:3.

[0016] Furthermore, the weight ratio of the methyl tributylidene oxime silane to the 3-aminopropyl triethoxy silane is 4:1.

[0017] Furthermore, the weight ratio of the thermoplastic layer mixture, the activated potassium titanate whisker and the silane mixture is 20:3:2.

[0018] A method for preparing a novel heat-sealed cover tape, the method comprising the following steps: The high-strength substrate layer and the thermoplastic layer with antistatic function are obtained by laminating under a pressure of 1 MPa.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention firstly modifies and optimizes the base material layer of the cover tape, and uses epoxy vinyl ester resin with good tensile strength and bonding strength and polysiloxane with good corrosion resistance and thermal stability, and obtains a high-strength base material layer with both stability and bonding strength through compounding and high-temperature blending. Then, by using the antistatic function of titanium dioxide, titanium dioxide is firstly uniformly mixed into styrene-butadiene rubber through methyl silicone resin, and then potassium titanate whiskers activated by dibutyltin dilaurate are added to make up for the shortcoming of small contact area of ​​conductive filler caused by point-like continuous distribution of titanium dioxide in styrene-butadiene rubber, and finally a silane mixture is added to fully connect the components, thereby improving the overall stability of the thermoplastic layer and realizing antistatic modification of the thermoplastic layer. The butadiene-styrene structure contained in styrene-butadiene rubber is easy to produce tensile strength structures such as carbon chains with longer and larger degrees of freedom and saturated carbon ring structures with good degrees of freedom during the polymerization process with tourmaline powder, which can easily allow the polymer to bend and rotate freely. As a result, the finally prepared thermoplastic layer with antistatic function has good flowability. The thermoplastic layer with antistatic function with good flowability can achieve good adhesion at a lower temperature, reducing the influence of excessively high temperature on the stability of the thermal sealing tape, thereby reducing the generation of static electricity when peeling off the cover tape and making the antistatic performance of the cover tape more stable and lasting. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be clearly and completely described below through the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0021] Unless otherwise specified, the raw materials and reagents used in the present invention are commercially available or can be prepared by known methods.

[0022] MFE-2 high-performance epoxy vinyl ester resin and MFE 722 high-performance epoxy vinyl ester resin were purchased from Huachang Polymer Co., Ltd. of East China University of Science and Technology; Styrene-butadiene rubber was purchased from Zhejiang Tianchen Rubber Industry Co., Ltd.; Titanium dioxide is purchased from Ishihara Industry Co., Ltd. of Japan; Silicone rubber and methyl silicone resin were purchased from Hubei Xinsihai Chemical Co., Ltd.; Potassium titanate whiskers were purchased from Nantong Aoxin Electronic Technology Co., Ltd. Methyl trisbutyl ketoxime silane and 3-aminopropyl triethoxy silane were purchased from Hubei New Blue Sky New Materials Co., Ltd.

[0023] Preparation Example 1: The method for preparing a high-strength substrate layer specifically includes the following steps: 3 parts by weight of cobalt cyclohexane are added to 1 part by weight of polysiloxane, and then 10 parts by weight of tetraethyl orthosilicate are added and stirred evenly to obtain a polysiloxane-tetraethyl orthosilicate mixture. Then 4 parts by weight of styrene, 1 part by weight of methyl ethyl ketone peroxide and 20 parts by weight of a polysiloxane-tetraethyl orthosilicate mixture are added to 20 parts by weight of MFE-2 high-performance epoxy vinyl ester resin and stirred evenly, and finally put into an extruder, the extruder is heated to 140°C, and the mixture is blended at a speed of 80r / min for 15 minutes. After the blending is completed, the obtained blend is poured into a flat mold and cooled naturally to form a high-strength substrate layer.

[0024] Preparation Example 2: The method for preparing a high-strength substrate layer specifically includes the following steps: 3 parts by weight of cobalt cyclohexane are added to 1 part by weight of polysiloxane, and then 10 parts by weight of tetraethyl orthosilicate are added and stirred evenly to obtain a polysiloxane-tetraethyl orthosilicate mixture. Then 4 parts by weight of styrene, 1 part by weight of methyl ethyl ketone peroxide and 20 parts by weight of a polysiloxane-tetraethyl orthosilicate mixture are added to 20 parts by weight of MFE-2 high-performance epoxy vinyl ester resin and stirred evenly, and finally put into an extruder, the extruder is heated to 140°C, and blended at a speed of 80r / min for 30 minutes. After the blending is completed, the obtained blend is poured into a flat mold and cooled naturally to form a high-strength substrate layer.

[0025] Preparation Example 3: The method for preparing a high-strength substrate layer specifically includes the following steps: 3 parts by weight of cobalt cyclohexane are added to 1 part by weight of polysiloxane, and then 10 parts by weight of tetraethyl orthosilicate are added and stirred to obtain a polysiloxane-tetraethyl orthosilicate mixture. Then 4 parts by weight of styrene, 1 part by weight of methyl ethyl ketone peroxide and 20 parts by weight of a polysiloxane-tetraethyl orthosilicate mixture are added to 20 parts by weight of MFE-2 high-performance epoxy vinyl ester resin and stirred to obtain a polysiloxane-tetraethyl orthosilicate mixture. Finally, the mixture is placed in an extruder, the extruder is heated to 160°C, and the mixture is blended at a speed of 80r / min for 15 minutes. After the blending is completed, the obtained blend is poured into a flat mold and cooled naturally to form a high-strength substrate layer.

[0026] Preparation Example 4: The method for preparing a high-strength substrate layer specifically includes the following steps: 3 parts by weight of cobalt cyclohexane are added to 1 part by weight of polysiloxane, and then 10 parts by weight of tetraethyl orthosilicate are added and stirred evenly to obtain a polysiloxane-tetraethyl orthosilicate mixture. Then 4 parts by weight of styrene, 1 part by weight of methyl ethyl ketone peroxide and 20 parts by weight of a polysiloxane-tetraethyl orthosilicate mixture are added to 20 parts by weight of MFE 722 high-performance epoxy vinyl ester resin and stirred evenly, and finally put into an extruder, the extruder is heated to 160°C, and the mixture is blended at a speed of 80r / min for 30 minutes. After the blending is completed, the obtained blend is poured into a flat mold and cooled naturally to form a high-strength substrate layer.

[0027] Preparation Example 5: The method for preparing a high-strength substrate layer specifically includes the following steps: 3 parts by weight of cobalt cyclohexane are added to 1 part by weight of polysiloxane, and then 10 parts by weight of tetraethyl orthosilicate are added and stirred evenly to obtain a polysiloxane-tetraethyl orthosilicate mixture. Then 4 parts by weight of styrene, 1 part by weight of methyl ethyl ketone peroxide and 20 parts by weight of a polysiloxane-tetraethyl orthosilicate mixture are added to 20 parts by weight of MFE 722 high-performance epoxy vinyl ester resin and stirred evenly, and finally put into an extruder, the extruder is heated to 140°C, and blended at a speed of 100r / min for 30min. After the blending is completed, the obtained blend is poured into a flat mold and cooled naturally to form a high-strength substrate layer.

[0028] Preparation Example 6: The method for preparing a high-strength substrate layer specifically includes the following steps: 3 parts by weight of cobalt cyclohexane are added to 1 part by weight of polysiloxane, and then 10 parts by weight of tetraethyl orthosilicate are added and stirred evenly to obtain a polysiloxane-tetraethyl orthosilicate mixture. Then 4 parts by weight of styrene, 1 part by weight of methyl ethyl ketone peroxide and 20 parts by weight of a polysiloxane-tetraethyl orthosilicate mixture are added to 20 parts by weight of MFE 722 high-performance epoxy vinyl ester resin and stirred evenly, and finally put into an extruder, the extruder is heated to 200°C, and the mixture is blended at a speed of 80r / min for 30 minutes. After the blending is completed, the obtained blend is poured into a flat mold and cooled naturally to form a high-strength substrate layer.

[0029] The high-strength substrate layers obtained in Preparation Examples 1 to 6 were tested for bonding strength and tensile strength according to GB / T 7124-2008 and ASTM D-897. The results are shown in Table 1: Table 1 Mechanical properties in conclusion: (1) It can be seen from the data in the above table that under certain preparation conditions, Preparation Examples 1 to 4 exhibit good bonding strength and tensile strength. This property helps to reduce the adverse effects caused by friction between the base material layer and the thermoplastic layer when the cover tape is subjected to external force.

[0030] (2) In Preparation Example 5, due to the excessively fast rotation speed, the tensile strength of the high-strength substrate layer is reduced, and deformation occurs easily when stretched. The static electricity generated by friction can cause damage to electronic components.

[0031] (3) In Preparation Example 6, due to the high temperature, the bonding strength of the high-strength substrate layer is reduced. When peeling off the cover tape, the possibility of separation between the substrate layer and the thermoplastic layer increases, causing damage to the electronic components.

[0032] Preparation Example 7: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: Add 3 parts by weight of silicone rubber, 2 parts by weight of methyl silicone resin and 1 part by weight of titanium dioxide to 10 parts by weight of styrene-butadiene rubber, disperse them by a high-speed disperser, and grind them with a three-roll grinder to a particle size of less than 50 μm to obtain a thermoplastic layer mixture. Stir 10 parts by weight of potassium titanate whiskers and 3 parts by weight of dibutyltin dilaurate to obtain activated potassium titanate whiskers. Stir 4 parts by weight of methyl tributylidene oxime silane and 1 part by weight of 3-aminopropyl triethoxysilane to obtain a silane mixture. Disperse 20 parts by weight of the thermoplastic layer mixture, 3 parts by weight of activated potassium titanate whiskers and 2 parts by weight of the silane mixture by a high-speed disperser, then heat to 80°C for a timed reaction of 10 hours, and dry naturally to obtain a thermoplastic layer with antistatic function.

[0033] Preparation Example 8: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: 3 parts by weight of silicone rubber, 2 parts by weight of methyl silicone resin and 1 part by weight of titanium dioxide are added to 10 parts by weight of styrene-butadiene rubber, dispersed by a high-speed disperser, and then ground by a three-roll grinder to a particle size of less than 50 μm to obtain a thermoplastic layer mixture. 10 parts by weight of potassium titanate whiskers and 3 parts by weight of dibutyltin dilaurate are stirred evenly to obtain activated potassium titanate whiskers. 4 parts by weight of methyl tributylidene oxime silane and 1 part by weight of 3-aminopropyl triethoxysilane are stirred evenly to obtain a silane mixture. 20 parts by weight of the thermoplastic layer mixture, 3 parts by weight of activated potassium titanate whiskers and 2 parts by weight of the silane mixture are dispersed by a high-speed disperser, then heated to 80°C for a timed reaction of 12 hours, and dried naturally to obtain a thermoplastic layer with antistatic function.

[0034] Preparation Example 9: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: Add 3 parts by weight of silicone rubber, 2 parts by weight of methyl silicone resin and 1 part by weight of titanium dioxide to 10 parts by weight of styrene-butadiene rubber, disperse them by a high-speed disperser, and grind them with a three-roll grinder to a particle size of less than 50 μm to obtain a thermoplastic layer mixture. Stir 10 parts by weight of potassium titanate whiskers and 3 parts by weight of dibutyltin dilaurate to obtain activated potassium titanate whiskers. Stir 4 parts by weight of methyl tributylidene oxime silane and 1 part by weight of 3-aminopropyl triethoxysilane to obtain a silane mixture. Disperse 20 parts by weight of the thermoplastic layer mixture, 3 parts by weight of activated potassium titanate whiskers and 2 parts by weight of the silane mixture by a high-speed disperser, then heat to 90°C for a timed reaction of 10 hours, and dry naturally to obtain a thermoplastic layer with antistatic function.

[0035] Preparation Example 10: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: 3 parts by weight of silicone rubber, 2 parts by weight of methyl silicone resin and 1 part by weight of titanium dioxide are added to 10 parts by weight of styrene-butadiene rubber, dispersed by a high-speed disperser, and then ground by a three-roll grinder to a particle size of less than 50 μm to obtain a thermoplastic layer mixture. 10 parts by weight of potassium titanate whiskers and 3 parts by weight of dibutyltin dilaurate are stirred evenly to obtain activated potassium titanate whiskers. 4 parts by weight of methyl tributylidene oxime silane and 1 part by weight of 3-aminopropyl triethoxysilane are stirred evenly to obtain a silane mixture. 20 parts by weight of the thermoplastic layer mixture, 3 parts by weight of activated potassium titanate whiskers and 2 parts by weight of the silane mixture are dispersed by a high-speed disperser, then heated to 90°C for a timed reaction of 12 hours, and dried naturally to obtain a thermoplastic layer with antistatic function.

[0036] Preparation Example 11: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: The thermoplastic layer mixture in Preparation Example 10 was replaced with a particle size less than 100 μm, and the other conditions remained the same as Preparation Example 10.

[0037] Preparation Example 12: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: The activated potassium titanate whiskers in Preparation Example 10 were removed, and the other conditions remained the same as those in Preparation Example 10.

[0038] Preparation Example 13: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: The silane mixture in Preparation Example 10 was removed, and the other conditions remained the same as those in Preparation Example 10.

[0039] Preparation Example 14: The method for preparing a thermoplastic layer with antistatic function specifically comprises the following steps: The silicone rubber in the thermoplastic layer mixture in Preparation Example 10 was removed, and the other conditions were kept the same as those in Preparation Example 10.

[0040] Embodiment 1: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The high-strength substrate layer obtained in Preparation Example 1 and the thermoplastic layer with antistatic function obtained in Preparation Example 7 were respectively controlled to have a thickness of 24 μm and 10 μm using a scraper coater, and then the high-strength substrate layer with a thickness of 24 μm and the thermoplastic layer with an antistatic function with a thickness of 10 μm were obtained by lamination pressure processing at 1 MPa.

[0041] Embodiment 2: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The high-strength substrate layer obtained in Preparation Example 2 and the thermoplastic layer with antistatic function obtained in Preparation Example 8 were respectively controlled to have a thickness of 24 μm and 10 μm using a scraper coater, and then the high-strength substrate layer with a thickness of 24 μm and the thermoplastic layer with an antistatic function with a thickness of 10 μm were obtained by lamination pressure processing at 1 MPa.

[0042] Embodiment 3: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The high-strength substrate layer obtained in Preparation Example 3 and the thermoplastic layer with antistatic function obtained in Preparation Example 9 were respectively controlled to have a thickness of 24 μm and 10 μm using a scraper coater, and then the high-strength substrate layer with a thickness of 24 μm and the thermoplastic layer with an antistatic function with a thickness of 10 μm were obtained by lamination pressure processing at 1 MPa.

[0043] Embodiment 4: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The high-strength substrate layer obtained in Preparation Example 4 and the thermoplastic layer with antistatic function obtained in Preparation Example 10 were respectively controlled to have a thickness of 24 μm and 10 μm using a scraper coater, and then the high-strength substrate layer with a thickness of 24 μm and the thermoplastic layer with an antistatic function with a thickness of 10 μm were obtained by lamination pressure processing at 1 MPa.

[0044] Embodiment 5: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The high-strength substrate layer obtained in Preparation Example 3 and the thermoplastic layer with antistatic function obtained in Preparation Example 10 were respectively controlled to have a thickness of 24 μm and 10 μm using a scraper coater, and then the high-strength substrate layer with a thickness of 24 μm and the thermoplastic layer with an antistatic function with a thickness of 100 μm were obtained by lamination pressure processing at 1 MPa.

[0045] Comparative Example 1: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The thermoplastic layer with antistatic function in Example 5 was replaced by the thermoplastic layer with antistatic function obtained in Preparation Example 11, and the other conditions were kept the same as in Example 5.

[0046] Comparative Example 2: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The thermoplastic layer with antistatic function in Example 5 was replaced by the thermoplastic layer with antistatic function obtained in Preparation Example 12, and the other conditions were kept the same as in Example 5.

[0047] Comparative Example 3: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The thermoplastic layer with antistatic function in Example 5 was replaced by the thermoplastic layer with antistatic function obtained in Preparation Example 13, and the other conditions were kept the same as in Example 5.

[0048] Comparative Example 4: A method for preparing a novel heat-sealed cover tape specifically includes the following steps: The thermoplastic layer with antistatic function in Example 5 was replaced by the thermoplastic layer with antistatic function obtained in Preparation Example 14, and the other conditions were kept the same as in Example 5.

[0049] Comparative Example 5: The thickness of the high-strength substrate layer and the thermoplastic layer with antistatic function in Example 5 were increased to 30 μm and 15 μm respectively, and the other conditions remained the same as in Example 5.

[0050] The surface resistance values ​​of the new heat-sealed cover tapes obtained in Examples 1 to 6 and Comparative Examples 1 to 5 were measured using an AS982 surface resistance tester. Heat sealing was then performed at 100° C. and the peel strength was measured. The results are shown in Table 2: Table 2 Performance test of new heat-sealing cover tape From the data in the above table, we can see that: (1) The new heat-sealing cover tapes of Examples 1 to 6 have lower surface resistance, and the surface resistance changes little after long-term storage. Moreover, heat sealing can be achieved at a relatively low temperature of 100°C, which reduces the adverse effects of high-temperature sealing on damage to electronic components. The peel strength after sealing is good, indicating that the heat sealing effect can be achieved.

[0051] (2) It can be seen from Comparative Example 1 that although it has a certain antistatic effect, due to the large particle size of the thermoplastic layer mixture, the titanium dioxide and potassium titanate whiskers are unevenly distributed, resulting in a small effective area and easy aggregation. Therefore, the antistatic effect and durability are not as good as those of Examples 1 to 6.

[0052] (3) It can be seen from Comparative Example 2 that although titanium dioxide has good electrical conductivity, its point-like continuous distribution characteristics result in a small contact area of ​​the conductive filler, so the antistatic effect is not as good as that of Examples 1 to 6.

[0053] (4) It can be seen from Comparative Example 3 that the removal of the silane mixture reduces the stability of the thermoplastic layer, causing the thermoplastic layer to become uneven during heat sealing, resulting in a slight unevenness on the sealing edge of the cover tape and a reduction in the peel strength.

[0054] (5) It can be seen from Comparative Example 4 that the removal of silicone rubber causes uneven bonding of the components of the thermoplastic layer, which reduces its thermoplastic properties at a heat-sealing temperature of 100°C, ultimately causing wrinkles and deformation of the cover tape during heat sealing.

[0055] (6) It can be seen from Comparative Example 5 that a cover tape that is too thick may require a higher temperature to achieve heat sealing, and high temperature is not conducive to the protection of electronic components.

[0056] The above-described embodiments provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected.

Claims

1. A novel heat-sealed cover tape, characterized in that: The heat-sealing cover tape is composed of a high-strength base material layer and a thermoplastic layer with antistatic function; The method for preparing the high-strength substrate layer comprises the following steps: mixing epoxy vinyl ester resin, styrene, methyl ethyl ketone peroxide and a polysiloxane-tetraethyl orthosilicate mixture to obtain a substrate layer mixture; The substrate layer mixture is blended at a temperature of 140° C. to 160° C. at a rotation speed of 80 r / min for 15 min to 30 min, and then poured into a mold and cooled naturally to form the high-strength substrate layer.

2. A novel heat-sealed cover tape according to claim 1, characterized in that: The weight ratio of the epoxy vinyl ester resin, styrene, methyl ethyl ketone peroxide and the polysiloxane-tetraethyl orthosilicate mixture is 20:4:0.1:

20.

3. A novel heat-sealed cover tape according to claim 1, characterized in that: The polysiloxane-tetraethyl orthosilicate mixture is prepared by mixing polysiloxane, cobalt cyclohexane and tetraethyl orthosilicate in a weight ratio of 1:3:

10.

4. A novel heat-sealed cover tape according to claim 1, characterized in that: The method for preparing the thermoplastic layer with antistatic function comprises the following steps: The styrene-butadiene rubber, silicone rubber, methyl silicone resin and titanium dioxide are mixed and ground to obtain a thermoplastic layer mixture; The potassium titanate whisker and dibutyltin dilaurate are mixed to obtain activated potassium titanate whisker; Mixing methyl tributylidene oxime silane and 3-aminopropyl triethoxy silane to obtain a silane mixture; The thermoplastic layer mixture, activated potassium titanate whiskers and silane mixture are mixed to obtain a reaction solution; The reaction solution is heated to 80° C. to 90° C. and reacted for 10 h to 12 h to obtain the thermoplastic layer with antistatic function.

5. A novel heat-sealed cover tape according to claim 4, characterized in that: The weight ratio of the styrene-butadiene rubber, silicone rubber, methyl silicone resin and titanium dioxide is 10:3:2:

1.

6. A novel heat-sealed cover tape according to claim 4, characterized in that: The weight ratio of the potassium titanate whisker to dibutyltin dilaurate is 10:

3.

7. A novel heat-sealed cover tape according to claim 4, characterized in that: The weight ratio of the methyl tributylidene oxime silane to the 3-aminopropyl triethoxy silane is 4:

1.

8. A novel heat-sealed cover tape according to claim 4, characterized in that: The weight ratio of the thermoplastic layer mixture, the activated potassium titanate whisker and the silane mixture is 20:3:

2.

9. A method for preparing a novel heat-sealing cover tape as claimed in any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: The high-strength substrate layer and the thermoplastic layer with antistatic function are obtained by laminating under a pressure of 1 MPa.

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