Electronic component packaging cover tape

Abstract

To provide an electronic component packaging cover tape hard to tear at the time of peeling from a carrier tape.SOLUTION: An electronic component packaging cover tape contains a base material layer and a seal layer provided on one side of the base material layer. The base material layer contains a polybutylene terephthalate film. In the polybutylene terephthalate film, tear strength in all of four directions (0° (MD), 45°, 90° (TD), 135°) of it is preferably 120 mN or more. In the polybutylene terephthalate film, out of the tear strength in the four directions (0° (MD), 45°, 90° (TD), 135°) of it, the ratio of a maximum value and a minimum value (maximum value / minimum value) is preferably 1.5 or below.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a cover tape for packaging electronic components, and more particularly to a cover tape that can be sealed to a carrier tape having a storage section for storing electronic components, among packaging materials that protect electronic components from contamination during storage and transportation of the electronic components and allow the electronic components to be removed when mounted. [Background technology]

[0002] Electronic components, including semiconductor integrated circuits, are often packaged in packaging materials consisting of a plastic carrier tape and a cover tape. During assembly, the cover tape is peeled off, and the electronic components are automatically mounted on an electronic circuit board. Such packaging materials require sufficient adhesive strength between the cover tape and the carrier tape to protect the packaged electronic components from contamination. However, if the adhesive strength between the cover tape and the carrier tape is too strong, problems such as the cover tape tearing during peeling from the carrier tape during the mounting process and remaining partially on the carrier tape, making it impossible to remove the electronic components, or mechanical issues with the mounting machine's peeling mechanism can lead to tape breakage caused by tiny tears in the cover tape. These problems can reduce yield and the operating rate of the mounting machine.

[0003] Various methods have been proposed to solve the problems caused by poor peeling between the cover tape and the carrier tape. For example, Patent Document 1 proposes a cover tape for packaging electronic components that can be heat-sealed to a plastic carrier tape, the cover tape comprising a base layer, a heat sealant layer, and an intermediate layer between the base layer and the heat sealant layer, the base layer being a laminate of two or more films selected from polyester, nylon, and polypropylene.By using a base layer consisting of two or more films selected from polyester, nylon, and polypropylene, the cover tape is prevented from tearing when peeled from the carrier tape. Patent Document 2 proposes a cover tape that is heat-sealed over a carrier tape formed of a long sheet with a plurality of recesses for accommodating electronic components spaced at predetermined intervals along the length of the carrier tape. The cover tape is constructed by laminating at least a substrate layer and an adhesive layer, and the substrate layer is made of a copolymer polyester whose dicarboxylic acid component is 80 to 95 mol % of terephthalic acid and 5 to 20 mol % of isophthalic acid, and whose diol component is 95 mol % or more of ethylene glycol and 5 mol % or less of diethylene glycol. The use of a substrate layer made of a copolymer polyester with a specific composition prevents tearing of the cover tape during the mounting process. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-156684 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-34355 Summary of the Invention [Problem to be solved by the invention]

[0005] The cover tape for packaging electronic components proposed in Patent Document 1 uses a base layer made of two or more laminated materials, which increases the number of steps required to manufacture the cover tape for packaging electronic components, thereby increasing manufacturing costs.In addition, the cover tape proposed in Patent Document 2 uses a copolymer polyester having a specific composition, which raises concerns about a decrease in the heat resistance of the cover tape. Furthermore, the method proposed in Patent Document 1 requires the preparation of two or more types of films, and the method proposed in Patent Document 2 requires the production of a copolymer polyester with a specific composition, making these methods complicated.

[0006] The present invention has been made in view of the above circumstances, and has as its object to provide a cover tape for packaging electronic components that is less likely to tear when peeled from the carrier tape. [Means for solving the problem]

[0007] As a result of intensive research conducted by the inventors to solve the above-mentioned problems, they discovered that in a cover tape comprising a base layer and a sealing layer provided on one side of the base layer, among various polyester films, a cover tape using a polybutylene terephthalate film as the base layer is less likely to tear when peeled off from the carrier tape and is suitable as a cover tape for packaging electronic components, and thus completed the present invention.

[0008] That is, the present invention relates to a cover tape having a polybutylene terephthalate film as a substrate layer, and the following [1] to [8] can be one form or one embodiment of the present invention. [1] a substrate layer; A seal layer provided on one side of the base material layer; A cover tape for packaging electronic components, comprising: The substrate layer comprises a polybutylene terephthalate film. Cover tape. [2] The cover tape according to [1], wherein the polybutylene terephthalate film has a tear strength of 120 mN or more in all four directions (0° (MD), 45°, 90° (TD), 135°) of the polybutylene terephthalate film. [3] The cover tape according to [2], wherein the polybutylene terephthalate film has a ratio (maximum / minimum) of the maximum to minimum tear strength of the polybutylene terephthalate film in four directions (0° (MD), 45°, 90° (TD), 135°) of 1.5 or less. [4] The cover tape according to [2] or [3], wherein the polybutylene terephthalate film has a tensile strength of 180 MPa or more in all four directions (0° (MD), 45°, 90° (TD), 135°) of the polybutylene terephthalate film. [5] The cover tape according to [2] or [3], wherein the polybutylene terephthalate film is a biaxially stretched polybutylene terephthalate film. [6] The cover tape according to [4], wherein the polybutylene terephthalate film is a biaxially oriented polybutylene terephthalate film. [7] The cover tape according to [5], wherein the cover tape is sealed to a carrier tape having a storage section for storing electronic components. [8] The cover tape according to [6], wherein the cover tape is sealed to a carrier tape having a storage section for storing electronic components. [Effects of the Invention]

[0009] According to the present invention, a cover tape for packaging electronic components that is resistant to tearing when peeled off from a carrier tape is provided. Therefore, the cover tape for packaging electronic components of the present invention can suppress a decrease in yield and operation rate of a mounting machine caused by poor peeling from the carrier tape. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of a cover tape for packaging electronic components of the present invention [(a) is a schematic cross-sectional view of a cover tape for packaging electronic components comprising a base layer and a seal layer; (b) is a schematic cross-sectional view of a cover tape for packaging electronic components comprising a base layer, an intermediate layer, and a seal layer]. [Figure 2] FIG. 2 is a schematic view showing an example of the electronic component packaging body of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Cover tape for packaging electronic components] The present invention provides a substrate layer; A seal layer provided on one side of the base material layer; A cover tape for packaging electronic components, comprising: The substrate layer comprises a polybutylene terephthalate film. Cover tape Regarding.

[0012] The cover tape for packaging electronic components (hereinafter also referred to as "cover tape") of the present invention will be described with reference to the drawings. Fig. 1 is a schematic cross-sectional view showing an example of the cover tape for packaging electronic components of the present invention. The layer structure constituting the cover tape 10 of the present invention can be, for example, a two-layer structure of a base layer 11 and a seal layer 12 [Fig. 1(a)], or a three-layer structure of a base layer 11, an intermediate layer 13, and a seal layer 12 [Fig. 1(b)]. Note that in the cover tape of the present invention, an adhesive layer (not shown) may be provided between each layer.

[0013] Next, each layer constituting the cover tape of the present invention will be described in detail. <Base layer: Polybutylene terephthalate film> By using a polybutylene terephthalate film as a substrate layer, a cover tape for packaging electronic components that is resistant to tearing when peeled from the carrier tape can be obtained. Furthermore, the polymerization of polybutylene terephthalate does not require the use of an antimony catalyst, which is used in the polymerization of polyethylene terephthalate. Therefore, the cover tape of the present invention, which uses a polybutylene terephthalate film as a substrate layer, is thought to be able to reduce the environmental impact during production compared to cover tapes that use the conventionally widely used general-purpose polyethylene terephthalate film as a substrate layer.

[0014] The polybutylene terephthalate that forms the polybutylene terephthalate film of the base layer that constitutes the cover tape of the present invention is not particularly limited as long as it is a polyester whose main repeating unit is butylene terephthalate, and specifically is a homopolymer type polyester (polybutylene terephthalate) obtained by condensing 1,4-butanediol or its ester-forming derivative as the diol (glycol component) and terephthalic acid or its ester-forming derivative as the dibasic acid component as the main components, or a copolymer type polyester whose main component is the polybutylene terephthalate.

[0015] In the present invention, in order to obtain the optimum mechanical strength characteristics in the polybutylene terephthalate film, the polybutylene terephthalate preferably has a melting point of 200°C to 250°C and an intrinsic viscosity (IV value) in the range of 0.90 dL / g to 1.35 dL / g, more preferably a melting point of 215°C to 225°C and an intrinsic viscosity (IV value) in the range of 1.15 dL / g to 1.30 dL / g. The intrinsic viscosity (IV value) of the polybutylene terephthalate is preferably phenyl. The solution viscosity was measured at 30°C using a mixed solvent of ethanol and tetrachloroethane (mass ratio 1 / 1).

[0016] The copolymer-type polyester (copolyester) mainly composed of polybutylene terephthalate is a polyester obtained by condensing a portion of the terephthalic acid component as a dibasic acid component with another dibasic acid component such as isophthalic acid, phthalic acid, adipic acid, or sebacic acid, and / or a portion of the 1,4-butanediol component as a diol (glycol) component with another diol (glycol) component such as ethylene glycol, diethylene glycol, propylene glycol, neopentyl glycol, or cyclohexanedimethanol. Preferred examples of the copolyester include those containing 70% or more butylene terephthalate units.

[0017] Furthermore, the polybutylene terephthalate used in the present invention may be mixed with other polyesters such as polyethylene terephthalate, polyethylene naphthalate, polyhexamethylene terephthalate, poly(ethylene terephthalate / ethylene isophthalate), and other resins such as polycarbonate and polyamide, to the extent that the physical properties are not impaired. Furthermore, the polybutylene terephthalate layer may be laminated with a layer formed from the other polyesters or other resins. Two or more types of the other polyesters and other resins may be used. Furthermore, two or more types of layers formed from the other polyesters and other resins may be used.

[0018] In the present invention, any of the following can be used for the polybutylene terephthalate film of the base layer constituting the cover tape of the present invention: a polybutylene terephthalate film consisting solely of polybutylene terephthalate as the resin component; a polybutylene terephthalate film consisting of a mixed resin containing polybutylene terephthalate as the resin component; and a polybutylene terephthalate film consisting of two or more layers laminated together with a polybutylene terephthalate layer and a layer formed from the other polyesters or other resins.

[0019] Furthermore, additives such as lubricants, antiblocking agents, inorganic fillers, antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, plasticizers, colorants, crystallization inhibitors, and crystallization accelerators may be added to the polybutylene terephthalate (or, in some cases, the above-mentioned other polyesters or other resins) used in the present invention, as needed. Furthermore, in order to avoid a decrease in viscosity due to hydrolysis during heat melting, it is preferable that the polybutylene terephthalate pellets used in film production have a moisture content of 0.05% by mass or less before heat melting, and more preferably, they are sufficiently pre-dried to have a moisture content of 0.02% by mass or less before use.

[0020] The polybutylene terephthalate film of the base layer constituting the cover tape of the present invention preferably has a tear strength of 120 mN or more in all four directions (0° (MD), 45°, 90° (TD), 135°) of the polybutylene terephthalate film, more preferably 150 mN or more, even more preferably 180 mN or more, and particularly preferably 200 mN or more. Furthermore, the polybutylene terephthalate film of the base layer constituting the cover tape of the present invention preferably has a ratio (maximum / minimum) of the maximum to minimum tear strength of the polybutylene terephthalate film in the four directions (0° (MD), 45°, 90°, 135° (TD)) of 1.5 or less, more preferably 1.4 or less, and even more preferably 1.3 or less. The tear strength is preferably 120 mN or more to prevent the cover tape from tearing during peeling from the carrier tape, leaving part of the cover tape on the carrier tape, or preventing the tape from being torn due to a tear in the cover tape. With a tear strength of 120 mN or more, even if a small tear occurs in the cover tape (for example, at the end of the cover tape) when peeled off, Since the tear strength of the entire cover tape exceeds the force required to peel the cover tape from the carrier tape, the carrier tape can be peeled from the cover tape without causing poor peeling between the carrier tape and the cover tape. Furthermore, even if the tear strength is strong in one direction, if the tear strength is weak in other directions, the force applied to peel the cover tape acts in the direction of the weak tear strength of the cover tape, which may result in the cover tape tearing and causing tape breakage. Therefore, it is preferable that the ratio of the maximum value to the minimum value (maximum value / minimum value) of the tear strengths in the above four directions is small, specifically 1.5 or less. The polybutylene terephthalate film of the base layer constituting the cover tape of the present invention preferably has a tensile strength of 180 MPa or more, more preferably 190 MPa or more, in all four directions (0° (MD), 45°, 90° (TD), and 135°) of the polybutylene terephthalate film, which significantly improves lamination suitability.

[0021] The polybutylene terephthalate film can be obtained by forming the polybutylene terephthalate into a film using an extruder. The obtained film may be stretched. An example of a method for producing the polybutylene phthalate film used for the base layer of the cover tape of the present invention will be described below. Polybutylene terephthalate is melt-kneaded in an extruder set at a predetermined temperature (for example, 210°C to 280°C). Next, the film is formed. The film forming method is not particularly limited. For example, in the case of T-die film formation, the sheet-shaped molten resin is immersed in a water tank to directly water-cool both the inside and outside. On the other hand, in the case of annular film formation, the film is extruded downward through an annular die attached to an extruder facing downward to form a molten tubular film. The film is then introduced into a cooling mandrel connected to the annular die, where cooling water introduced from each nozzle of the cooling mandrel directly contacts the inside of the molten tubular film to cool it. At the same time, cooling water is also flowed from an external cooling tank used in combination with the cooling mandrel, and the cooling water also directly contacts the outside of the molten tubular film to cool it. The temperature of the internal and external water is preferably 30°C or less, and from the perspective of rapid film formation, 20°C or less is particularly preferred. Temperatures higher than 30°C can lead to whitening of the unstretched film, poor appearance of the unstretched film due to boiling of the cooling water, and stretching can become increasingly difficult.

[0022] To stably produce a biaxially oriented polybutylene terephthalate film, it is necessary to minimize crystallization of the unstretched film before stretching. As described above, when a polybutylene terephthalate melt extruded by an extruder is cooled to form a film, the polybutylene terephthalate is cooled to the crystallization temperature range at a certain rate or higher. In other words, the cooling rate of the unstretched film is an important factor. The cooling rate of the unstretched film is 200°C / sec or higher, preferably 250°C / sec or higher, and particularly preferably 350°C / sec or higher. If the cooling rate is less than 200°C / sec, the crystallinity of the resulting unstretched film may be high, resulting in reduced stretchability. The method for producing the unstretched film is not particularly limited as long as it satisfies the cooling rate of the unstretched film. From the viewpoint of rapid cooling film production, however, the above-mentioned internal and external direct water cooling method is particularly preferred.

[0023] The method for biaxially stretching the unstretched film is not particularly limited and may be appropriately selected from, for example, a simultaneous biaxial stretching method in which longitudinal stretching and transverse stretching are performed simultaneously using a tubular system or a tenter system, or a sequential biaxial stretching method in which longitudinal stretching and transverse stretching are performed sequentially, etc. The simultaneous biaxial stretching method using a tubular system is particularly preferred from the viewpoint of obtaining a biaxially stretched polybutylene terephthalate film with smaller anisotropy and higher tear strength and tensile strength in any direction 360°. Considering the stretching stability and the strength properties and thickness uniformity of the resulting biaxially stretched polybutylene terephthalate film, the stretching ratio is preferably in the range of 2.7 to 4.0 times in both the machine direction (hereinafter also referred to as "MD") and the transverse direction (hereinafter also referred to as "TD"). If the stretching ratio is less than 2.7 times, the resulting biaxially stretched polybutylene terephthalate film will have a low stretching ratio. This is undesirable because the tensile strength and impact strength of the terephthalate film may be insufficient. Furthermore, if the stretching ratio exceeds 4.0, excessive strain is generated in the molecular chains due to stretching, which may result in frequent breakage or puncture during stretching, making stable production impossible. The stretching temperature is preferably in the range of 40°C to 80°C, and particularly preferably 45°C to 65°C. Unstretched films produced at the above-mentioned high cooling rates have low crystallinity and can therefore be stably stretched at relatively low stretching temperatures. High-temperature stretching above 80°C can cause the stretching bubble to oscillate violently, resulting in significant stretching irregularities and the risk of failing to obtain a film with good thickness precision. On the other hand, low-temperature stretching at temperatures below 40°C can cause excessive stretch-oriented crystallization due to low-temperature stretching, leading to whitening of the film and, in some cases, the stretching bubble can burst, making it difficult to continue stretching. By carrying out such biaxial stretching processing, it is possible to obtain a biaxially stretched polybutylene terephthalate film with little anisotropy.

[0024] The obtained biaxially stretched polybutylene terephthalate film can be placed in a heat treatment facility using a hot roll system, a tenter system, or a combination of these for a desired period of time, and heat-treated at, for example, 180°C to 240°C, particularly preferably 190°C to 210°C, to obtain a biaxially stretched polybutylene terephthalate film with excellent thermal dimensional stability. If the heat treatment temperature is higher than 240°C, the bowing phenomenon may become too large, increasing the anisotropy in the width direction. On the other hand, if the heat treatment temperature is lower than 180°C, the thermal dimensional stability of the film may be significantly reduced, which may cause problems in the heat pressing process.

[0025] In addition, at least one surface of the obtained biaxially stretched polybutylene terephthalate film may be subjected to an adhesion-enhancing treatment using corona, plasma, ultraviolet light, etc., or an in-line or offline adhesion-enhancing coating, in order to improve adhesion to other layers.

[0026] The thickness of the substrate layer constituting the cover tape of the present invention can be appropriately designed within a range that does not impair the effects of the present invention, and is usually 10 μm to 50 μm, taking into consideration transportability, winding ability, etc.

[0027] <Sealing layer> The sealing layer that constitutes the cover tape of the present invention is a layer that is placed on one side of the base layer, and is a layer that adheres to the carrier tape when the cover tape is sealed (e.g., heat sealed) to the carrier tape. The sealing layer may be, for example, a heat-sealing layer, a pressure-sensitive adhesive layer, or a heat-activatable adhesive layer.

[0028] Examples of resins that form the heat seal layer include polyolefin resins (e.g., polyethylene, polypropylene, and polybutylene), ethylene-vinyl acetate copolymers (EVA), ethylene-acrylic acid copolymers, ethylene-methacrylic acid copolymers, and ethylene-styrene copolymers, and two or more types of resins that form the heat seal layer may be used.

[0029] The ethylene-vinyl acetate copolymer may be a copolymer containing at least ethylene monomer units and vinyl acetate monomer units. The ethylene content in the ethylene-vinyl acetate copolymer is not particularly limited, but is, for example, 60% to 97% by mass, and preferably 80% to 95% by mass. The vinyl acetate content in the ethylene-vinyl acetate copolymer is not particularly limited, but is, for example, 3% to 40% by mass, and preferably 5% to 20% by mass. The ethylene-vinyl acetate copolymer may contain a third monomer unit in addition to the ethylene monomer unit and the vinyl acetate monomer unit. The third monomer unit may contain a functional group having antistatic properties.

[0030] Examples of the pressure-sensitive adhesive that forms the pressure-sensitive adhesive layer include acrylic pressure-sensitive adhesives and rubber-based pressure-sensitive adhesives. Examples of the pressure-sensitive adhesive include pressure-sensitive adhesives and silicone-based pressure-sensitive adhesives, and two or more types of pressure-sensitive adhesives may be used to form the pressure-sensitive adhesive layer.

[0031] Examples of adhesives that form the heat-activatable adhesive layer include polyvinyl acetate adhesives, polyvinyl alcohol adhesives, ethylene-vinyl alcohol copolymer adhesives, and vinyl chloride-vinyl acetate copolymer adhesives, and two or more types of adhesives may be used to form the heat-activatable adhesive layer.

[0032] The sealing layer constituting the cover tape of the present invention may also contain an antistatic agent, thereby improving the antistatic properties of the cover tape. Examples of antistatic agents include metal oxides (e.g., tin oxide, zinc oxide, and titanium oxide), conductive polymers (e.g., polythiophene, polyaniline, polypyrrole, and derivatives thereof), and surfactants (e.g., quaternary ammonium salts, polyoxyethylene alkyl ethers, and alkyl sulfonates), and two or more types of antistatic agents may be used. When the sealing layer contains an antistatic agent, its content is not particularly limited, but may be, for example, 1% by mass or more, 5% by mass or more, or 7% by mass or more based on the total mass of the sealing layer. If the content of the antistatic agent is less than 1% by mass, appropriate antistatic properties may not be achieved. Alternatively, the content of the antistatic agent may be, for example, 25% by mass or less, 20% by mass or less, or 15% by mass or less. If the content of the antistatic agent exceeds 25% by mass, dispersibility may be poor, which may adversely affect adhesion, mechanical properties, etc. Furthermore, the sealing layer constituting the cover tape of the present invention may contain an antiblocking agent, a dispersant for improving the dispersibility of the antistatic agent, a colorant, etc., as required.

[0033] The thickness of the sealing layer constituting the cover tape of the present invention can be designed appropriately within a range that does not impair the effects of the present invention, and may be, for example, 1 μm or more, or 5 μm or more, or 10 μm or more, or 15 μm or more, or 50 μm or less, or 40 μm or less, or 30 μm or less, or 20 μm or less.

[0034] <Middle class> The cover tape of the present invention may have an intermediate layer between the base layer and the seal layer. By providing an intermediate layer, the cushioning properties of the cover tape can be improved. The intermediate layer may be one layer or two or more layers.

[0035] The resin forming the intermediate layer is not particularly limited and examples thereof include polyethylene, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid ester copolymer, and ethylene-vinyl acetate copolymer (EVA), and two or more resins may be used to form the intermediate layer. Among these, polyethylene is preferred as the resin forming the intermediate layer, and low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE) is more preferred. The thickness of the intermediate layer may be, for example, 5 μm or more, or 10 μm or more, or 15 μm or more, and may be, for example, 50 μm or less, or 40 μm or less, or 30 μm or less.

[0036] <Adhesive layer> The cover tape of the present invention may have an adhesive layer between each layer, which can improve the adhesion between the layers. The adhesive layer can be formed from a resin with good adhesiveness, such as a polyolefin-based, polyester-based, isocyanate-based, or polyurethane-based adhesive. The thickness of the adhesive layer is, for example, 1 g / cm 2 or more, or 2 g / cm 2 or more, or 3 g / cm 2 It may be more than 10 g / cm 2 or less, or 7g / cm 2 or less than 5g / cm 2 It may be the following:

[0037] The cover tape of the present invention may be provided with an antistatic layer in addition to the above-mentioned substrate layer, seal layer, intermediate layer and adhesive layer.

[0038] The thickness of the cover tape of the present invention is not particularly limited as long as it does not inhibit adhesion to the carrier tape, but may be, for example, 20 μm or more, or 30 μm or more, or 40 μm or more, or may be, for example, 150 μm or less, or 80 μm or less, or 70 μm or less.

[0039] The method for producing the cover tape for packaging electronic components of the present invention is not particularly limited, and examples thereof include a method in which a base layer, a sealing layer, and, if an intermediate layer is interposed between these layers, the intermediate layer are laminated by a dry lamination method to obtain the cover tape.

[0040] [Electronic component packaging] The present invention provides a carrier tape having a storage portion for storing electronic components; an electronic component housed in the housing; a cover tape for packaging electronic components that covers the storage section of the carrier tape; The present invention relates to an electronic component packaging body comprising:

[0041] The electronic component packaging body of the present invention will be described with reference to the drawings. 2 is a schematic diagram showing an example of an electronic component packaging body of the present invention. In an electronic component packaging body 20, a cover tape 10 is used to cover a storage section 22 of a carrier tape 21. That is, the cover tape 10 is used as a lid material for the carrier tape 21, which has a recessed storage section 22 that matches the shape of an electronic component 23.

[0042] The carrier tape constituting the electronic component packaging body of the present invention is not particularly limited, and examples thereof include a paper or resin film embossed to fit the dimensions of the electronic component. Examples of resins that form the carrier tape include polystyrene, polyester, polypropylene, polycarbonate, polyacrylonitrile, and acrylonitrile-butadiene-styrene copolymer. These resins may contain an antistatic agent or a conductive filler.

[0043] The electronic components constituting the electronic component packaging of the present invention are not particularly limited, and examples thereof include semiconductor chips, transistors, diodes, capacitors, piezoelectric elements, optical elements, LED-related members, connectors, and electrodes.

[0044] The cover tape for packaging electronic components constituting the electronic component packaging body of the present invention is as described above.

[0045] The method for producing the electronic component packaging body is not particularly limited, and examples thereof include a method including a step of storing electronic components in a storage section of a carrier tape, and a step of sealing (e.g., heat sealing) a cover tape for packaging electronic components to the surface of the carrier tape so as to cover the storage section of the carrier tape.

[0046] The electronic component packaging of the present invention is used for storing and transporting electronic components. The electronic components are stored and transported in the electronic component packaging state and are then mounted. At the time of mounting, the cover tape for packaging electronic components is peeled off from the carrier tape, the electronic components housed in the carrier tape are removed, and the electronic components are mounted on a substrate or the like. [Example]

[0047] Examples of the present invention and comparative examples are shown below, but the present invention is not limited to these examples.

[0048] Example 1 Polybutylene terephthalate pellets (homotype, melting point = 224°C, IV value = 1.26 dl / g) dried in a hot air dryer at 140°C for 5 hours were melt-kneaded in an extruder under conditions of cylinder and die temperatures of 210°C to 260°C, and a molten tubular thin film was extruded downward from an annular die. Subsequently, the film was passed through the outer diameter of a cooling mandrel, folded by a carapace roll, and then taken up by a take-up nip roll at a speed of 1.2 m / min. The unstretched film produced under these conditions was transported to a low-speed nip roll in an atmosphere of 20°C and subjected to simultaneous longitudinal and transverse biaxial stretching using a tubular method. The stretch ratios were 3.1 times in the MD and 3.2 times in the TD, and the stretching temperature was 60°C. Next, this biaxially stretched film was placed in a hot roll type heat treatment equipment and then in a tenter type heat treatment equipment, and subjected to heat treatment at 210°C to obtain a biaxially stretched polybutylene terephthalate film. The thickness of this biaxially stretched polybutylene terephthalate film was 15 µm. The biaxially oriented polybutylene terephthalate film thus obtained as the base layer and the EVA film (SB-5 manufactured by Tamapoly Co., Ltd.: thickness 30 μm) as the sealing layer (heat sealing layer) were dry laminated [adhesive (main agent: DIC Dry LX-703VL, curing agent: KR-90) (manufactured by DIC Graphics Co., Ltd.)] (adhesive layer thickness: 4.2 g / cm 2 ) to obtain a cover tape for packaging electronic components.

[0049] <Example 2> A cover tape was obtained in the same manner as in Example 1, except that the melt-kneading extrusion amount was changed and the thickness of the biaxially stretched polybutylene terephthalate film was set to 25 μm.

[0050] <Comparative Example 1> A cover tape was obtained in the same manner as in Example 1, except that the base layer was changed to a biaxially stretched polyethylene terephthalate film (E5102 manufactured by Toyobo Co., Ltd.: thickness 16 μm).

[0051] <Comparative Example 2> A cover tape was obtained in the same manner as in Comparative Example 1, except that the thickness of the biaxially stretched polyethylene terephthalate film for the base layer was changed to 25 μm (E5102 manufactured by Toyobo Co., Ltd.).

[0052] The tear strength and tensile strength of the base layer films used in Examples 1 and 2 and Comparative Examples 1 and 2 were measured by the following methods, and the results are shown in Table 1. The tear strength of the cover tapes of Examples 1 and 2 and Comparative Examples 1 and 2 was also measured, and the results are shown in Table 1.

[0053] <Evaluation items> [Tear strength] Tear strength was measured using a light-load tear tester (No. 193 Model D) manufactured by Toyo Seiki Seisakusho Co., Ltd., under an atmosphere of 23°C and 50% RH. Specifically, a sample was cut to a width of 50 mm and a length of 63.5 mm (tear direction). A 12.7 mm cut was made from the center edge of the width direction (short side) parallel to the tear direction (long side). The fixed ends formed by the cut were each fixed to a clamp, and the sample was torn using a pendulum and weight. The energy required (tear strength) was calculated for each of the four directions (0° (MD), 45°, 90° (TD), and 135°). Tear strength was calculated using the following formula.

number

[0054] [Tensile strength] The tensile strength was measured using a Tensilon universal material testing machine RTC-1210A manufactured by Orientec Co., Ltd. on samples cut to a width of 15 mm and a length of 200 mm, with a chuck distance of 100 mm and a tensile speed of 200 mm / min, in each of four directions (0° (MD), 45°, 90° (TD), 135°), and the strength at break was recorded as the tensile strength.

[0055] [Table 1]

[0056] As shown in Table 1, the tear strength of the polybutylene terephthalate film in all four directions (0° (MD), 45°, 90° (TD), 135°) was high at 205 mN or more, and the ratio of the maximum to the minimum tear strength (maximum / minimum) was small at 1.3 or less, so there was no significant difference in tear strength depending on the tear direction (Examples 1 and 2).In contrast, the tear strength of the polyethylene terephthalate film used in conventional cover tapes was low at 83 mN or more in all four directions, and the ratio of the maximum to the minimum tear strength (maximum / minimum) was large at 2.3 or less, so there was a significant difference in tear strength depending on the tear direction (Comparative Examples 1 and 2). Therefore, when comparing the cover tape of Example 2, which uses a polybutylene terephthalate film as the base layer, with the cover tape of Comparative Example 2, which uses a polyethylene terephthalate film as the base layer, it is clear that the cover tape of the present invention has significantly higher tear strength in all four directions than the conventional cover tape. Therefore, it is thought that the cover tape of the present invention has sufficient tear strength and is therefore less likely to tear when peeled from the carrier tape. [Explanation of symbols]

[0057] 10. Cover tape for packaging electronic components 11 Base material layer 12 Sealing layer 13 Middle class 20 Electronic component packaging 21 Carrier tape 22 Storage area 23 Electronic Components

Claims

1. a substrate layer; A seal layer provided on one side of the base material layer; A cover tape for packaging electronic components, comprising: The substrate layer comprises a polybutylene terephthalate film. Cover tape.

2. 2. The cover tape of claim 1, wherein the polybutylene terephthalate film has a tear strength of 120 mN or more in all four directions (0° (MD), 45°, 90° (TD), and 135°) of the polybutylene terephthalate film.

3. 3. The cover tape of claim 2, wherein the polybutylene terephthalate film has a ratio (maximum value / minimum value) of the maximum to minimum tear strengths of the polybutylene terephthalate film in four directions (0° (MD), 45°, 90° (TD), 135°) of 1.5 or less.

4. The cover tape according to claim 2 or 3, wherein the polybutylene terephthalate film has a tensile strength of 180 MPa or more in all four directions (0° (MD), 45°, 90° (TD), 135°) of the polybutylene terephthalate film.

5. 4. The cover tape according to claim 2, wherein the polybutylene terephthalate film is a biaxially oriented polybutylene terephthalate film.

6. The cover tape of claim 4 , wherein the polybutylene terephthalate film is a biaxially oriented polybutylene terephthalate film.

7. 6. The cover tape according to claim 5, wherein the cover tape is sealed to a carrier tape having a storage section for storing an electronic component.

8. 7. The cover tape according to claim 6, wherein the cover tape is sealed to a carrier tape having a storage section for storing an electronic component.

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