Cap tape and electronic component package

Abstract

The cover tape has at least a base material layer and a heat-seal layer, the heat-seal layer containing a polystyrene-based resin (A) and an ethylene-(meth)acrylic acid-based copolymer (B), the content of the (A) component and the (B) component being greater than 80 parts by mass and 95 parts by mass or less and 5 parts by mass or more and less than 20 parts by mass, respectively, relative to 100 parts by mass of the total of the (A) component and the (B) component.

Description

Technical Field

[0001] This invention relates to cover straps and packaging for electronic components. Background Technology

[0002] With the miniaturization of electronic devices, the miniaturization and high performance of the electronic components used are also developing. In the assembly process of electronic devices, a step of automatically mounting components on a printed circuit board is implemented. In the handling of such surface-mount electronic components, in order to continuously supply electronic components, an electronic component package is used to hold the electronic components in a carrier tape with continuously heat-formed pockets corresponding to the shape of the electronic components.

[0003] The electronic component packaging is manufactured by placing the electronic component in the recess of a carrier tape, then overlapping a cover tape with a heat-sealing layer on the upper surface of the carrier tape as a cover material, and continuously heat-sealing both ends of the cover tape along the length direction using a heated heat-sealing rod (see, for example, Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2010-173673 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In recent years, significant progress has been made in the miniaturization, weight reduction, and thinning of various electronic components such as capacitors, resistors, ICs, LEDs, connectors, and switching elements, and the number of components mounted on substrates has also gradually increased. Therefore, from the perspective of improving the productivity of electronic component packaging, the demand for high-speed sealing of cap tapes is gradually increasing. Furthermore, from an energy-saving perspective, there is a need to reduce the energy required for heat sealing.

[0009] As a means to address these requirements, one could consider lowering the softening temperature of the heat seal layer on the cover tape. However, in this case, as the softening temperature of the heat seal layer decreases, there is a tendency for the tapes to stick together easily and become stuck together.

[0010] The present invention was made in view of the above circumstances, and its object is to provide a cover tape that inhibits adhesion and can be heat-sealed with less heat energy, and an electronic component packaging body using the same.

[0011] Methods for solving problems

[0012] To address the aforementioned issues, one aspect of the present invention provides a cover tape having at least a substrate layer and a heat-sealing layer, the heat-sealing layer containing a polystyrene resin (A) and an ethylene-(meth)acrylic acid copolymer (B), wherein the contents of component (A) and component (B) are greater than 80 parts by mass and less than 95 parts by mass and more than 5 parts by mass and less than 20 parts by mass, respectively, relative to a total of 100 parts by mass of component (A) and component (B).

[0013] The aforementioned cover tape is less prone to sticking and can be heat-sealed with less heat energy. This prevents production line stoppages caused by sticking and enables high-speed and low-temperature heat sealing, thereby improving productivity and energy efficiency in the manufacturing of electronic component packaging.

[0014] The above component (A) may include copolymers of styrene-based hydrocarbons and conjugated diene-based hydrocarbons, and impact-resistant polystyrene. In this case, stable peel strength is easily ensured.

[0015] From the viewpoint of providing a seal with less heat and inhibiting adhesion, the above-mentioned component (B) may include an ethylene-methyl methacrylate copolymer.

[0016] Another aspect of the present invention provides an electronic component packaging body comprising: a carrier tape having a receiving portion; an electronic component received in the receiving portion of the carrier tape; and a cover tape that is heat-sealed to the carrier tape as a cover material.

[0017] Invention Effects

[0018] According to the present invention, a cover tape that inhibits adhesion and can be heat-sealed with less heat energy, and an electronic component packaging using the same, can be provided. Attached Figure Description

[0019] [ Figure 1 This is a schematic cross-sectional view illustrating an embodiment of the cover strip.

[0020] [ Figure 2 This is a partial cut-out perspective view illustrating one embodiment of an electronic component package. Detailed Implementation

[0021] The preferred embodiments of the present invention will now be described in detail.

[0022] [Cover strap]

[0023] The cover strip of this embodiment includes at least a substrate layer and a heat-sealing layer.

[0024] Figure 1 A schematic cross-sectional view illustrating an embodiment of the cover strip. Figure 1The cover strip 50 shown in (a) includes a substrate layer 1, a heat-sealing layer 2 disposed on one side of the substrate layer 1, and an intermediate layer 3 disposed between the substrate layer 1 and the heat-sealing layer 2. Additionally, Figure 1 The cover strip 52 shown in (b) has two intermediate layers 3a and 3b between the substrate layer 1 and the heat-sealing layer 2. The cover strip of this embodiment can be a double-layer structure without intermediate layers, or it can have a structure in which a layer such as an antistatic layer is also provided on the side of the substrate layer 1 opposite to the heat-sealing layer 2. Furthermore, without compromising the heat-sealing properties of the heat-sealing layer, the cover strip of this embodiment can also have a structure in which an antistatic layer or similar layer is provided on the side of the heat-sealing layer 2 opposite to the substrate layer 1.

[0025] (Substrate layer)

[0026] The substrate layer can be a film obtained by forming a resin composition comprising one or more thermoplastic resins selected from polyethylene terephthalate, polyethylene naphthalate, and other polyester resins, polyolefin resins such as polypropylene, polyamide resins such as nylon, polystyrene resins, polyethylene resins, and polycarbonate resins. For these films, from the viewpoint of mechanical strength, biaxially stretched films are preferred, and from the viewpoint of transparency and toughness, biaxially stretched polyethylene terephthalate films are more preferred.

[0027] Examples of polystyrene-based resins include polystyrene, high-impact polystyrene (HIPS), styrene-butadiene copolymers or their hydrogenated forms, styrene-isoprene copolymers or their hydrogenated forms, styrene-ethylene graft copolymers, styrene-butene-butadiene copolymers, and methacrylic acid-styrene copolymers, all of which contain styrene units in a molar ratio of 1 / 2 or higher in their molecular chains. These resins can be used alone or in combination (as a mixture) of two or more.

[0028] Examples of polyethylene-based resins include low-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene, ethylene-α-olefin, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymer, ethylene-(meth)acrylate methyl acrylate copolymer, ethylene-(meth)acrylate ethyl acrylate copolymer, and ethylene-propylene rubber, which are resins containing ethylene units in a molar ratio of 1 / 2 or more in the molecular chain. These resins can be used alone or in combination (in the form of a mixture) of two or more.

[0029] From the perspective of obtaining extrusion stability during membrane fabrication, various additives such as commonly used antioxidants and lubricants can be added to the substrate layer.

[0030] The substrate layer can be a single layer or have a multi-layer structure.

[0031] From the perspective of mechanical strength and thermal conductivity during heat sealing, the thickness of the substrate layer can be 5–100 μm, 10–80 μm, or 12–30 μm.

[0032] (Middle layer)

[0033] The intermediate layer may be provided to ensure a strong bond between the substrate layer and the heat-sealing layer, and may comprise a thermoplastic resin. Examples of thermoplastic resins include:

[0034] (i) Polyethylene resins such as low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene;

[0035] (ii) ethylene-1-butene, copolymers of ethylene and unsaturated carboxylic acids, copolymers of ethylene-(meth)acrylate, copolymers of ethylene-vinyl acetate, and terpolymers formed further with acid anhydrides, and mixtures thereof;

[0036] (iii) Styrene-ethylene graft copolymers, styrene-propylene graft copolymers, styrene-ethylene-butadiene block copolymers, and mixtures thereof;

[0037] etc.

[0038] Considering the above-mentioned objectives and ease of layer formation, the thermoplastic resin is preferably a polyethylene-based resin, and more preferably a low-density polyethylene resin or a linear low-density polyethylene resin.

[0039] Furthermore, the intermediate layer can have a structure of two or more layers. In this case, the extrusion stability of the heat-sealing layer can be improved by producing a co-extruded film of the heat-sealing layer and the intermediate layer, and the adhesion between the co-extruded film and the substrate layer can be improved by utilizing other intermediate layers. For an intermediate layer with a structure of two or more layers, for example, the side in contact with the heat-sealing layer may be a first intermediate layer containing one or more of the resins shown in (i), (ii), and (iii) above, and the side in contact with the substrate layer may be a second intermediate layer containing one or more of the resins shown in (i) and (ii) above.

[0040] From the perspective of obtaining extrusion stability during membrane fabrication, various additives such as commonly used antioxidants and lubricants can be added to the intermediate layer.

[0041] From the perspective of ensuring the adhesion strength between the substrate layer and the heat-sealing layer and the peel strength of the cover tape, the thickness of the intermediate layer can be 3-70 μm, 5-60 μm, or 10-50 μm.

[0042] The cover strip of this embodiment may have two or more substrate layers and / or intermediate layers. For example, the substrate layer and intermediate layer may have a three-layer structure of substrate layer / intermediate layer / substrate layer, or a four-layer structure of intermediate layer / substrate layer / intermediate layer / substrate layer.

[0043] In this embodiment, when the cover tape has two or more substrate layers and / or intermediate layers, known adhesives can be used to ensure strong adhesion between the layers. Examples of adhesives include isocyanate-based adhesives and ethyleneimine-based adhesives. From the viewpoint of preventing a large deviation in the peel strength of the cover tape, the thickness of the adhesive layer is preferably 5 μm or less.

[0044] (Heat-sealing layer)

[0045] The heat-sealing layer may contain a polystyrene-based resin (A) (hereinafter sometimes referred to as component (A)) and an ethylene-(meth)acrylic acid copolymer (B) (hereinafter sometimes referred to as component (B)). Cover tapes with such heat-sealing layers easily ensure sealing for carrier tapes made of various materials, such as polystyrene and polycarbonate.

[0046] In the heat-sealing layer, component (A) may include copolymers of styrene-based hydrocarbons and conjugated diene-based hydrocarbons, and impact-resistant polystyrene, or mixtures thereof.

[0047] Examples of styrene-based hydrocarbons include styrene, α-methylstyrene, and various alkyl-substituted styrene compounds. Examples of conjugated diene hydrocarbons include butadiene and isoprene.

[0048] For the heat-sealing layer, from the viewpoint that the peel strength of the cover tape can easily become stable, as component (A), it may contain styrene-butadiene copolymer and impact-resistant polystyrene, or a mixture thereof.

[0049] From the viewpoint of adjusting peel strength and film-forming properties, component (A) may contain 50% to 95% by mass of a block copolymer of styrene hydrocarbons and 5% to 50% by mass of conjugated diene hydrocarbons (A-1) (hereinafter also referred to as component (A-1)). It may also contain 10% to 50% by mass of a block copolymer of styrene hydrocarbons and 50% to 90% by mass of conjugated diene hydrocarbons (A-2) (hereinafter also referred to as component (A-2)). Finally, it may contain impact-resistant polystyrene (A-3) (hereinafter also referred to as component (A-3)). In this case, the respective proportions relative to a total of 100 parts by mass of components (A-1), (A-2), and (A-3) may be as follows: component (A-1) is 20 to 40 parts by mass, component (A-2) is 35 to 60 parts by mass, and component (A-3) is 5 to 15 parts by mass.

[0050] Examples of ethylene-(meth)acrylic acid copolymers (B) include ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), and ethylene-glycidyl methacrylate-methyl acrylate copolymer (EGMA-MA). They can be used individually or in combination (as a mixture) with two or more types.

[0051] For component (B), considering the sealing performance under less heat and the inhibition of adhesion, the ethylene content can be 60-95% by mass or 65-90% by mass.

[0052] From the perspective of obtaining extrusion stability during film fabrication, various additives such as commonly used antioxidants and lubricants can be added to the heat seal layer.

[0053] From the viewpoint of suppressing adhesion and enabling heat sealing with less heat energy, the content of component (A) and component (B) in the heat-sealing layer can be set to greater than 80 parts by mass and less than 95 parts by mass, and more than 5 parts by mass and less than 20 parts by mass, respectively, relative to a total of 100 parts by mass of component (A) and component (B). Alternatively, it can be 82 parts by mass and less than 95 parts by mass, and more than 5 parts by mass and less than 18 parts by mass. Furthermore, from the viewpoint of extraction, the content of component (A) and component (B) in the heat-sealing layer can be 84 parts by mass and less than 95 parts by mass, and more than 5 parts by mass and less than 16 parts by mass, respectively, relative to a total of 100 parts by mass of component (A) and component (B). Alternatively, it can be 85 parts by mass and less than 95 parts by mass, and more than 5 parts by mass and less than 15 parts by mass.

[0054] The total content of component (A) and component (B) in the heat seal layer, based on the total amount of the heat seal layer, can be 50% or more by mass, 70% or more by mass, 90% or more by mass, or 100% by mass.

[0055] The aforementioned layers can be film-formed using methods such as blow molding, T-die molding, casting, or calendering. In this case, the components constituting each layer can be blended using a Henschel mixer, drum mixer, or MAZELAR mixer, and then directly film-formed using an extruder. Alternatively, the blend can be temporarily compounded and extruded using a single-screw or twin-screw extruder to obtain granules, which can then be further extruded using an extruder for film-forming.

[0056] The heat-sealing layer can be formed by the following methods: extrusion molding such as blow molding or T-die extrusion to form a film; dissolving the above-mentioned components (A) and (B) in a solvent and applying them to the film of the substrate layer; and applying it in the form of an aqueous emulsion; etc.

[0057] When the film for the heat-sealing layer is formed by extrusion molding, co-extrusion with the intermediate layer is preferred to improve extrusion stability. For example, the resin constituting the intermediate layer and the resin constituting the heat-sealing layer can be melt-blended separately using different single-screw or twin-screw extruders, and then the two can be laminated together through a feed head and a manifold die before being extruded from a T-die, thereby obtaining a double-layer film composed of the intermediate layer and the heat-sealing layer.

[0058] In addition, the heat-sealing film obtained by extrusion molding can be laminated with the substrate layer using conventional methods such as dry lamination and extrusion lamination to form a cover strip.

[0059] The overall thickness of the cover tape can be set to 30–100 μm, 35–80 μm, or 40–70 μm. Within this range, it is easy to ensure the strength and sealing performance of the tape.

[0060] The cover tape of this embodiment is suitable for packaging electronic components. Examples of electronic components include ICs (intelligence-emitting diodes), LEDs (light-emitting diodes), resistors, liquid crystals, capacitors, transistors, piezoelectric resistors, filters, quartz oscillators, quartz resonators, diodes, connectors, switches, potentiometers, relays, inductors, etc. The electronic components can be intermediate products using the above-mentioned components or final products.

[0061] In the aforementioned applications, to prevent dust adhesion and dissipate the electrostatic charge on the cover tape itself, it is preferable to impart antistatic properties to the substrate layer and the heat-sealing layer. Regarding the imparting of antistatic properties, commonly used antistatic agents include surfactant-type agents, conductive metal oxide particles, and electronically conductive polymers. These antistatic agents can also be incorporated into the resin depending on the desired properties, but from the viewpoint of efficiently achieving the desired effect, they can be applied to both surfaces of the cover tape using a gravure coating machine or similar equipment.

[0062] For example, the cover tape used for packaging electronic components can be heat-sealed onto the carrier tape.

[0063] Carrier tapes can be configured with recesses for housing electronic components using methods such as air molding and vacuum forming. Materials suitable for carrier tapes include easily sheet-forming materials such as polyvinyl chloride (PVC), polystyrene (PS), polyesters (A-PET, PEN, PET-G, PCTA), polypropylene (PP), polycarbonate (PC), polyacrylonitrile (PAN), and acrylonitrile-butadiene-styrene copolymer (ABS). These resins can be used alone or in combination. Carrier tapes can also be laminates formed from multiple layers.

[0064] The cover tape of this embodiment can be used in combination with carrier tapes such as polystyrene carrier tapes and polycarbonate carrier tapes.

[0065] <Electronic Component Packaging>

[0066] The electronic component packaging body of this embodiment includes: a carrier tape having a storage portion for storing electronic components; electronic components stored in the storage portion of the carrier tape; and a cover tape of this embodiment, which is heat-sealed onto the carrier tape as a cover material.

[0067] Figure 2 A partial cut-out perspective view illustrating one embodiment of an electronic component package. Figure 2 The electronic component packaging 200 shown includes an embossed carrier tape 16 with a storage section 20, an electronic component 40 stored in the storage section 20, and a cover film 50 heat-sealed to the embossed carrier tape 16. The embossed carrier tape 16 has transport holes 30 for handling in processes such as the encapsulation of various electronic components, including ICs. Additionally, a hole for inspecting the electronic component is provided at the bottom of the storage section 20 (not shown).

[0068] Regarding electronic components and carrier tapes, the aforementioned electronic components and carrier tapes can be cited as examples.

[0069] The electronic component packaging of this embodiment can be used for the storage and handling of electronic components in the form of a carrier material wound into a roll.

[0070] The electronic component packaging of this embodiment can be manufactured by a method comprising a process of heat-sealing the cover tape of this embodiment onto a carrier tape in which the electronic components are housed in a storage section.

[0071] The heat sealing of the cover tape can be achieved using a component called a sealing soldering iron, which applies a specified amount of heat and pressure to the heat-sealing layer. The cover tape can be heat-sealed onto the carrier tape surface by pressing such a sealing soldering iron against the carrier tape from above. Specifically, methods include repeated sealing by pressing the sealing soldering iron repeatedly while moving the embossed carrier tape, and continuous sealing by continuously pressing the sealing soldering iron against the side of the cover tape.

[0072] The sealing temperature can be 100-240℃ or 120-220℃.

[0073] According to the manufacturing method described above, by using the cover tape of this embodiment, it is possible to achieve high-speed and low-temperature heat sealing, thereby improving productivity and energy saving in the manufacturing of electronic component packaging.

[0074] Example

[0075] The present invention will be described in more detail below with reference to embodiments and comparative examples, but the present invention is not limited to the following embodiments.

[0076] (Example 1)

[0077] A resin composition constituting a heat-sealing layer was obtained by compounding 35 parts by weight of styrene-butadiene copolymer (manufactured by Denka Co., Ltd., product name "CLEAREN 170ZR", styrene / butadiene mass ratio = 83 / 17) as a polystyrene-based resin, 55 parts by weight of styrene-butadiene copolymer (manufactured by JSR Co., Ltd., product name "TR2000", styrene / butadiene mass ratio = 40 / 60), 5 parts by weight of high-impact polystyrene (manufactured by Toyo Styrene, product name "HIPS H870"), and 5 parts by weight of ethylene-(meth)acrylic acid copolymer (manufactured by Sumitomo Chemical Co., Ltd., product name "ACRYFT WH303-F", methyl methacrylate content: 18% by weight, ethylene content: 82% by weight) as an ethylene-(meth)acrylic acid-based copolymer. Using a T-die co-extrusion method, a bilayer film (total thickness 30 μm) was obtained from the resin composition and linear low-density polyethylene (UBE-MARUZEN POLYETHYLENE CO.,LTD., product name "UMERIT 2040F") as the first intermediate layer, consisting of a first intermediate layer (20 μm thick) and a heat-sealing layer (10 μm thick). This bilayer film was then laminated with a biaxially stretched polyethylene terephthalate film (Toyobo Co., Ltd., product name "Ester Film E5100", 16 μm thick) through a second intermediate layer (13 μm thick) formed of low-density polyethylene resin, resulting in the cover tape of Example 1.

[0078] (Examples 2-8, Comparative Examples 1-3)

[0079] The polystyrene resin and ethylene-(meth)acrylic acid copolymer were prepared with the composition shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the cover tapes of Examples 2-8 and Comparative Examples 1-3, respectively.

[0080] The details of the raw materials shown in Table 1 are as follows.

[0081] SBC: Styrene-butadiene copolymer (manufactured by Denka Co., Ltd., product name "CLEAREN 170ZR", styrene / butadiene mass ratio = 83 / 17)

[0082] SBR: Styrene-butadiene copolymer (manufactured by JSR Corporation, product name "TR2000", styrene / butadiene mass ratio = 40 / 60)

[0083] HIPS: High Impact Polystyrene (manufactured by Toyo Styrene, product name "HIPS H870")

[0084] EMMA: Ethylene-methyl methacrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd., product name "ACRYFTWH303-F", methyl methacrylate content: 18% by mass, ethylene content: 82% by mass)

[0085] EGMA-MA: Ethylene-glycidyl methacrylate-methyl acrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd., product name "BONDFAST BF-7M", glycidyl methacrylate content: 6% by mass, methyl acrylate content: 27% by mass, ethylene content: 67% by mass)

[0086] EMA: Ethylene-methyl acrylate copolymer (manufactured by Japan Polyethylene Corporation, product name "Rexpearl EB240H", methyl acrylate content: 20% by mass, ethylene content: 80% by mass)

[0087] EEA: Ethylene-ethyl acrylate copolymer (manufactured by UBE-MARUZEN POLYETHYLENE CO.,LTD., product name "UBE Polyethylene ZE735", ethyl acrylate content: 19% by mass, ethylene content: 81% by mass)

[0088] The cover strips of each embodiment and each comparative example were evaluated using the following methods. The results are shown in Table 1.

[0089] [Evaluation of Low-Temperature Sealing Performance]

[0090] Using a wrapping machine (manufactured by Nagata Seiki Co., Ltd., product name "NK-600"), a 21.5 mm wide cover tape was heat-sealed onto a 24 mm wide polystyrene carrier tape (manufactured by Denka Co., Ltd., product name "EC-R") under the following conditions: sealing head width 0.5 mm × 2, sealing head length 24 mm, sealing pressure 0.5 kgf, feed length 12 mm, sealing time 0.3 seconds, and sealing soldering iron temperature 140°C. Then, in an atmosphere with a temperature of 23°C and a relative humidity of 50%, the cover tape was peeled off at a peeling speed of 300 mm per minute and a peeling angle of 170° to 180°. The peel strength was measured, and the low-temperature sealing performance was evaluated according to the following criteria.

[0091] <Judgment Criteria>

[0092] A: Peel strength is above 0.2N.

[0093] C: Peel strength less than 0.2N

[0094] [Evaluation of anti-adhesion properties]

[0095] After the cover tape, which is made into a 21.5mm wide recording tape, is left to stand for 1 day in an atmosphere with a temperature of 23℃ and a relative humidity of 50%, it is pulled out at a speed of 2000mm per minute, and the load during the extraction is measured using a digital display force gauge.

[0096] In addition, pull out the cover tape by hand to check for adhesion, and evaluate the adhesion resistance according to the following judgment criteria.

[0097] A: No adhesion

[0098] B: There is adhesion in some areas.

[0099] C: The whole structure is adhered.

[0100] [Table 1]

[0101]

[0102] As shown in Table 1, it was confirmed that the cover tapes of Examples 1 to 8 inhibited adhesion and could be heat-sealed with less heat energy.

[0103] On the other hand, the cover tape of Comparative Example 1, whose heat-sealing layer does not contain ethylene-(meth)acrylic acid copolymer, has low peel strength when sealed at low temperature. The cover tapes of Comparative Examples 2 and 3, whose heat-sealing layer contains ethylene-(meth)acrylic acid copolymer exceeding the scope of the present invention, also experience high load and adhesion during extraction.

[0104] Explanation of reference numerals in the attached figures

[0105] 1…substrate layer, 2…heat seal layer, 3, 3a, 3b…intermediate layer, 16…embossed carrier tape, 20…storage section, 30…transport hole, 40…electronic component, 50, 52…cover tape, 200…electronic component packaging body.

Claims

1. A cover strip having at least a substrate layer and a heat-sealing layer, The heat-sealing layer contains component A and component B, wherein component A is a polystyrene-based resin and component B is an ethylene-(meth)acrylic acid copolymer. Relative to a total of 100 parts by mass of component A and component B, the contents of component A and component B are respectively greater than 80 parts by mass and less than 95 parts by mass, and greater than 5 parts by mass and less than 20 parts by mass. Component A comprises a copolymer of styrene hydrocarbons and conjugated diene hydrocarbons, and impact-resistant polystyrene. Component A comprises components A-1, A-2, and A-3. Component A-1 is a block copolymer of 50% to 95% by mass of styrene-based hydrocarbons and 5% to 50% by mass of conjugated diene hydrocarbons. Component A-2 is a block copolymer of 10% to 50% by mass of styrene-based hydrocarbons and 50% to 90% by mass of conjugated diene hydrocarbons. Component A-3 is impact-resistant polystyrene. The respective proportions of component A-1, component A-2, and component A-3 relative to a total of 100 parts by mass of component A-1, component A-2, and component A-3 are as follows: component A-1 is 20 to 40 parts by mass, component A-2 is 35 to 60 parts by mass, and component A-3 is 5 to 15 parts by mass.

2. The cover strip as claimed in claim 1, wherein, Component B contains an ethylene-methyl methacrylate copolymer.

3. An electronic component packaging body comprising: a carrier tape having a receiving portion; an electronic component received in the receiving portion of the carrier tape; and a cover tape as claimed in claim 1 or 2, the cover tape being heat-sealed onto the carrier tape as a cover material.

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