Cover tape for electronic component packaging and electronic component package

Abstract

The electronic component packaging cover tape of the present invention comprises a substrate layer and a sealant layer disposed on one side of the substrate layer. In this cover tape, the surface of the sealant layer opposite to the substrate layer side is an exposed surface. The peak density Spd of this exposed surface, as defined in ISO 25178, is 3 × 10⁻⁶. 5 ~1×10 6 / mm 2 The root mean square slope Sdq of the exposed surface, as defined in ISO 25178, is 1.0 × 10⁻⁶. ‑2 ~5.0×10 ‑1 .

Description

Technical Field

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

[0002] Electronic components such as transistors, diodes, capacitors, piezoelectric elements, and resistors are sometimes transported in the form of "electronic component packages" to prevent damage. These packages are housed within recesses in a carrier tape, which are then heat-sealed onto the carrier tape to seal the electronic components within the recesses. Electronic component packages are frequently imported and exported across borders by air and sea.

[0003] For packaged electronic components, peel off the cap tape from the packaging and remove the component from the recess when using it.

[0004] The prior art for the cover tape (cover tape for packaging electronic components) expected in the above-mentioned usage method can be listed in the following patent documents.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent document 1: Japanese Patent Application Publication No. 2017-171393.

[0008] Patent Document 2: International Publication No. 2012 / 079258.

[0009] Patent document 3: Japanese Patent Application Publication No. 2003-246358. Summary of the Invention

[0010] The technical problem to be solved by the invention

[0011] Through exploring previous improvements to cover straps, the inventors discovered that there is still room for improvement in the following aspects (i) and (ii).

[0012] (i) Blocking: The cover tape is usually long and is in a rolled-up state before use. At this time, there is a situation where the cover tape sticks to each other and becomes difficult to peel off.

[0013] (ii) Component adhesion: In electronic component packages obtained by heat-sealing a cover tape to a carrier tape, electronic components housed in recesses of the carrier tape may sometimes adhere to the cover tape due to vibrations during transport. If this adhesion occurs, it becomes difficult to properly remove the electronic components when peeling the cover tape off the carrier tape.

[0014] The present invention was made in view of this situation. One of the objects of the present invention is to provide a cover tape for packaging electronic components that inhibits adhesion and prevents the attachment of parts.

[0015] means for solving technical problems

[0016] To address the aforementioned problems, the inventors explored improvements to the cover tape from various perspectives. Through this exploration, it was discovered that the surface condition (exposed surface) of the sealant layer in the cover tape appears to be related to adhesion and the attachment of electronic components. Based on this insight, the inventors completed the invention described below. Furthermore, the aforementioned problems were resolved.

[0017] 1. A cover strip for packaging electronic components, comprising a substrate layer and a sealant layer disposed on one side of the substrate layer, wherein,

[0018] The surface of the sealant layer opposite to the substrate layer becomes the exposed surface.

[0019] The peak density Spd of the exposed surface, as defined in ISO 25178, is 3 × 10⁻⁶. 5 ~1×10 6 / mm 2 ,

[0020] The root mean square slope Sdq of the exposed surface, as defined in ISO 25178, is 1.0 × 10⁻⁶. -2 ~5.0×10 -1 .

[0021] 2. The cover strip as described in 1, wherein,

[0022] The arithmetic mean height Sa of the exposed surface, as defined in ISO 25178, is 0.05–0.5 μm.

[0023] 3. The cover strip as described in 1 or 2, wherein,

[0024] The sealant layer contains inorganic particles.

[0025] 4. The cover strip as described in any one of 1 to 3, wherein,

[0026] The sealant layer contains one or both of styrene-based resin and (meth)acrylic resin.

[0027] 5. The cover strip as described in any one of 1 to 4, wherein,

[0028] The substrate layer contains polyester.

[0029] 6. The cover strip as described in any one of 1 to 5, wherein the cover strip has an intermediate layer between the substrate layer and the sealant layer.

[0030] 7. The cover strip as described in 6, wherein,

[0031] The intermediate layer contains polyethylene resin.

[0032] 8. An electronic component package, wherein the electronic component package comprises a carrier strap for receiving electronic components in a recess and a cover strap as described in any one of 1 to 7.

[0033] The sealant layer is bonded to the carrier tape to seal the electronic component.

[0034] The effects of the invention

[0035] According to the present invention, a cover tape for packaging electronic components is provided that inhibits adhesion and prevents the attachment of components. Attached Figure Description

[0036] Figure 1 This is a diagram schematically illustrating an example of the layered structure of the cover strip.

[0037] Figure 2 This diagram illustrates an example of the state in which the cover tape and carrier tape are joined (heat-sealed). Detailed Implementation

[0038] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0039] In all the accompanying drawings, the same symbols are used to denote the same constituent elements, and descriptions are omitted where appropriate.

[0040] To avoid redundancy, there are two situations: (i) when multiple identical constituent elements exist in the same attached drawing, only one of them is labeled, not all of them; (ii) especially in Figure 2 In the future, regarding Figure 1 The same constituent elements are not re-labeled.

[0041] All accompanying drawings are for illustrative purposes only. The shape or size ratio of the parts in the drawings may not correspond to the actual objects.

[0042] Unless otherwise specified, the expression "X~Y" in the description of numerical ranges in this specification means above X and below Y. For example, "1~5% by mass" means "more than 1% by mass and less than 5% by mass".

[0043] The term "(meth)acrylic acid" in this specification includes both acrylic acid and methacrylic acid. The same applies to terms such as "(meth)acrylate".

[0044] <Packaging tape for electronic components>

[0045] Figure 1 This is a schematic diagram illustrating an example of the layer structure of the electronic component packaging cover strip (cover strip 10) of this embodiment.

[0046] The cover strip 10 has a substrate layer 1 and a sealant layer 3 disposed on at least one side of the substrate layer 1. The surface of the sealant layer 3 opposite to the side of the substrate layer 1 is an exposed surface (in contact with air).

[0047] The cover strip 10 preferably has an intermediate layer 2 between the substrate layer 1 and the sealant layer 3.

[0048] The peak density Spd of the exposed surface of sealant layer 3, as defined in ISO 25178, is 3 × 10⁻⁶. 5 ~1×10 6 / mm 2 Preferably 3.5×10 5 ~9×10 5 / mm 2 More preferably 3.5×10 5 ~8×10 5 / mm 2 .

[0049] Furthermore, the root mean square slope Sdq of the exposed surface of sealant layer 3, as defined in ISO 25178, is 1.0 × 10⁻⁶. -2 ~5.0×10 -1 Preferably 5.0×10 -2 ~5.0×10 -1 Further preferred is 1.0×10 -1 ~3.5×10 -1 .

[0050] The reason why adhesion and component attachment are suppressed by keeping Spd and Sdq within appropriate numerical ranges can be explained as follows. For the sake of caution, the following description contains speculation, and the invention is not limited to the following description.

[0051] Peak density Spd represents the density of peaks per 1 mm of surface area of ​​the object being measured. 2 The number of peaks exceeding the specified size. Unless otherwise specified, the specified size is set to the height of 5% of the maximum amplitude of the profile surface.

[0052] Spd is 3×10 5 / mm 2 The above refers to the presence of "protrusions" of a certain density on the exposed surface of the sealant layer 3. Therefore, it is believed that the reduced contact area between the electronic components and the sealant layer 3 can suppress adhesion. Furthermore, it is believed that the reduced contact area between the substrate layer 1 and the sealant layer 3 during the winding of the cover tape 10 can also suppress adhesion.

[0053] On the other hand, if Spd is too large, defects may occur in aspects other than the contact area. For example, cover tapes or electronic component packages are sometimes inspected by cameras. In this case, if Spd is too large, it may hinder the image inspection. Therefore, in this embodiment, the upper limit of Spd is set to 1×10. 6 / mm 2 .

[0054] The root mean square slope Sdq is an index calculated by taking the root mean square of the slopes at all points in the defined region, representing the average local slope of the surface. For a perfectly flat surface, Sdq is 0.

[0055] Although the details are still unclear, it is believed that Sdq is 1.0 × 10. -2 ~5.0×10 -1 The surface of the sealant layer 3 has appropriate unevenness or undulation, thus reducing the contact area between the electronic components and the sealant layer 3 and suppressing the adhesion of the electronic components. Sdq is assumed to be 1.0 × 10⁻⁶. -2 The above refers to the fact that there are fewer flat surfaces due to the appropriate slope on the surface of the sealant layer 3. Therefore, it is believed that when the cover tape 10 is wound up, the contact area between the substrate layer 1 and the sealant layer 3 becomes smaller, which can suppress adhesion.

[0056] On the other hand, if Sdq is too large, adhesion may easily occur because the unevenness or undulation of the sealant layer 3 engages with the unevenness or undulation that may exist on the surface of the sealant layer 1. Therefore, in this embodiment, the upper limit of Sdq is set to 5.0 × 10 -1 .

[0057] Spd and Sdq are both indicators related to the surface properties of the sealant layer 3. In the cover tape 10, since both of these indicators are optimized, adhesion can be suppressed, and component adhesion can be suppressed. According to the inventors' research, even if one of Spd and Sdq is optimized, adhesion can still easily occur and / or component adhesion cannot be sufficiently suppressed if the other is not optimized.

[0058] The cover tape 10 can be obtained using appropriate materials and appropriate manufacturing methods / conditions. For example, by paying close attention to the viscosity of the coating liquid used to form the sealant layer and the formation conditions of the sealant layer, it is possible to manufacture the cover tape 10 with Spd and Sdq values ​​within an appropriate range. Specifically, by paying attention to coating the surface of the intermediate layer 2 with a solvent-containing coating liquid adjusted to an appropriate viscosity, and by using appropriate equipment to dry the solvent at an appropriate temperature and for an appropriate time when drying the solvent to form the sealant layer, it is possible to manufacture the cover tape 10 with Spd and Sdq values ​​within an appropriate range.

[0059] Details regarding the manufacturing method of the cover strip will be discussed later.

[0060] The following is a more detailed explanation of the cover strip 10.

[0061] [Substrate Layer]

[0062] The material constituting the substrate layer 1 is not particularly limited. Any film can be used as long as it has the mechanical strength to withstand the external force applied to the cover strip 10 and the heat resistance to withstand the heat during heat sealing.

[0063] Specific examples of materials constituting the substrate layer 1 include polyester resins, polyamide resins, polyolefin resins, polyacrylate resins, polymethacrylate resins, polyimide resins, polycarbonate resins, and ABS resins. Among these, polyester resins and polyolefin resins are preferred as materials constituting the substrate layer 1, and polyester resins that can improve mechanical strength are particularly preferred, especially polyethylene terephthalate.

[0064] The film used to form the substrate layer 1 can be a stretched film, or a film stretched along a uniaxial direction or a biaxial direction. From the viewpoint of improving the mechanical strength of the cover strip 10, a film stretched along a uniaxial direction or a biaxial direction is preferred.

[0065] The substrate layer 1 can be a single layer or multiple layers.

[0066] From the viewpoint of reducing the amount of static electricity generated during the peeling of the carrier tape, the substrate layer 1 may contain an antistatic agent. Furthermore, an antistatic layer may also be provided as a layer in the substrate layer 1 on the surface opposite to the surface where the intermediate layer 2 is provided.

[0067] The thickness of the substrate layer 1 is, for example, 6 to 35 μm, preferably 7 to 33 μm, and more preferably 8 to 30 μm.

[0068] Since the thickness of the substrate layer 1 will not be too large, the rigidity of the cover tape will not become too high. Moreover, even if torsional stress is applied to the sealed carrier tape, the possibility of the cover tape 10 peeling off due to deformation of the carrier tape can be reduced.

[0069] Because the thickness of the substrate layer 1 is not too thin, the mechanical strength of the cover tape 10 is easily made suitable. Moreover, even when the cover tape 10 is peeled off from the carrier tape at high speed, the possibility of the cover tape 10 breaking can be reduced.

[0070] [Middle Layer]

[0071] The intermediate layer 2 is primarily designed to improve the cushioning of the cover tape 10. By improving the cushioning of the cover tape 10, the pressure of the sealing soldering iron can be easily and fully transmitted to the cover tape 10 during heat sealing. Therefore, the seal between the cover tape 10 and the carrier tape can be further improved.

[0072] The material of the intermediate layer 2 is not particularly limited. Materials that impart cushioning to the cover strip 10 can be used without particular restriction. Examples include one or more selected from polyacrylic acid derivatives, polyacrylate derivatives, polyvinyl acetate derivatives, styrene-based resins, olefin-based resins, cyclic olefin resins, and polymers thereof. Among these, polyolefin-based resins are preferred, and polyethylene-based resins are more suitable. In terms of cushioning, low-density polyethylene (density 880 kg / m³) is particularly preferred. 3 Above and below 930 kg / m 3 (polyethylene).

[0073] The intermediate layer 2 can be a single layer or multiple layers.

[0074] From the viewpoint of further improving the adhesion between the cover tape 10 and the carrier tape during heat sealing, the thickness of the intermediate layer 2 is typically 10 to 50 μm, preferably 15 to 45 μm.

[0075] [Sealant layer]

[0076] The sealant layer 3 is disposed on at least one side of the substrate layer 1. When an intermediate layer 2 is present, the sealant layer 3 is disposed on the surface side of the intermediate layer 2 opposite to the surface that contacts the substrate layer 1. As described above, the peak density Spd of the exposed surface of the sealant layer 3, as defined in ISO 25178, is 3 × 10⁻⁶. 5 ~1×10 6 / mm 2 Furthermore, the root mean square slope Sdq of the exposed surface of sealant layer 3, as defined in ISO 25178, is 1.0 × 10⁻⁶. -2 ~5.0×10 -1 .

[0077] When the cover tape 10 is heat-sealed to the carrier tape, the sealant layer 3 comes into contact with the carrier tape. By heating with a sealing soldering iron, the sealant layer 3 softens or melts and bonds with the carrier tape.

[0078] The sealant layer 3 preferably contains a thermoplastic resin. Specifically, the sealant layer 3 contains one or more resins selected from (meth)acrylic resins, styrene resins, olefin resins, urethane resins, and ester resins. Among these, (meth)acrylic resins and styrene resins are preferred from the viewpoint of good heat-sealing properties and good dispersion of inorganic particles.

[0079] Specific examples of (meth)acrylamide resins include resins having structural units derived from monomers such as acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc.; methacrylates such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, etc.; and monomers such as acrylonitrile, methacrylonitrile, acrylamide, etc. (Meth)acrylic resins may contain structural units derived from one or more monomers from these examples. Of course, (meth)acrylic resins may further contain structural units derived from monomers other than those in these examples, or they may not contain any.

[0080] Specific examples of styrene-based resins include polystyrene, styrene-butadiene copolymer (SB), styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-butene-styrene block copolymer (SEBS), styrene-butadiene-butene-styrene block copolymer (SBBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-(meth)methyl acrylate copolymer, hydrogenated styrene block copolymer, high impact polystyrene (HIPS), and general-purpose polystyrene resin (GPPS). Among these, from the perspective of balancing various properties, styrene-ethylene-butene-styrene block copolymer (SEBS) or styrene-butadiene-butene-styrene block copolymer (SBBS) are preferred.

[0081] Ester resins are typically composed of structural units derived from alcohols and structural units derived from carboxylic acids.

[0082] Specific examples of alcohol components include chain or branched aliphatic diols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 2,2-dimethyl-1,3-propanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol; alicyclic diols such as hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and epoxide adducts of hydrogenated bisphenol A with 2 or more but less than 4 carbon atoms (with an average molar number of addition of 2 or more but less than 12); and polyols with 3 or more members such as glycerol, pentaerythritol, trimethylolpropane, and sorbitol. One or more of these alcohol components may be used.

[0083] Specific examples of carboxylic acid components include chain or branched aliphatic dicarboxylic acids such as oxalic acid, malonic acid, maleic acid, fumaric acid, citracic acid, itaconic acid, pentenic acid, succinic acid, adipic acid, sebacic acid, dodecanoic acid, azelaic acid, dodecyl succinic acid, dodecenyl succinic acid, and octenyl succinic acid; polycarboxylic acids with three or more members such as trimellitic acid or its anhydrides; and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid. One or more of these carboxylic acid components may be used.

[0084] The sealant layer 3 preferably contains inorganic particles. By using inorganic particles, the state of the exposed surface of the sealant layer 3 can be adjusted, making it easier to set Spd and Sdq to the desired values. This can sometimes make it easier to suppress adhesion or component adhesion. Furthermore, by using inorganic particles, it can sometimes be expected to improve peelability from the carrier tape.

[0085] As a type of inorganic particle, particles containing metallic elements can be listed. These particles possess high electrical conductivity due to the presence of metals, thus enabling them to function as antistatic agents. By using particles containing metallic elements, damage to the electronic components of packaged items due to static electricity can be reduced.

[0086] Specifically, particles containing metallic elements can be listed as metal oxides such as aluminum oxide, tin oxide, zinc oxide, indium oxide, and titanium oxide, as well as sulfides such as zinc sulfide, copper sulfide, cadmium sulfide, nickel sulfide, and palladium sulfide.

[0087] Furthermore, although they may not necessarily contain metallic elements, carbon microparticles and other particles can be cited as examples of particles with antistatic properties.

[0088] Based on factors such as ease of acquisition and ease of adjusting peel strength, metal oxides are preferred as particles containing metal elements.

[0089] In particular, from the viewpoint of electrical conductivity, trace elements can be doped into particles containing metallic elements to improve conductivity. Examples of trace elements include antimony and indium. Particularly preferred antistatic agents are ITO (indium tin oxide) or ATO (antimony-doped tin oxide).

[0090] The average particle size of the inorganic particles is preferably 1 to 1000 nm, more preferably 3 to 500 nm. By selecting inorganic particles with an appropriate average particle size, it is easy to obtain effects that improve other properties without excessively compromising the transparency of the sealant layer 3.

[0091] The average particle size of inorganic particles can be determined by averaging at least 100 circular equivalent diameters of inorganic particles in a microscope image.

[0092] When inorganic particles are used, their amount depends on the intended use of the inorganic particles and their specific gravity, but is 40-80% by mass, preferably 50-70% by mass, in the total amount of sealant layer 3 (the non-volatile component in the coating liquid for forming the sealant layer in the method for manufacturing the cover tape described later). Furthermore, based on volume, the amount of inorganic particles used in the total amount of sealant layer 3 is preferably 10-40% by volume, more preferably 15-35% by volume.

[0093] On the exposed surface of sealant layer 3, preferably, the arithmetic mean height Sa, as defined in ISO 25178, is within an appropriate numerical range, except for Spd and Sdq. By ensuring that Sa is within an appropriate numerical range, further improvements in various properties can be expected.

[0094] Specifically, Sa is typically 0.05–0.5 μm, preferably 0.1–0.4 μm, and more preferably 0.1–0.3 μm.

[0095] From the viewpoint of obtaining sufficient heat-sealing properties without excessively impairing other properties, the thickness (dry film thickness) of the sealant layer 3 is preferably 0.05 to 5 μm, more preferably 0.1 to 3 μm.

[0096] [Overall Thickness]

[0097] From the viewpoint of ensuring a balance between strength and processability, the overall thickness of the cover strip 10 is preferably 30 to 65 μm, more preferably 35 to 60 μm.

[0098] <Manufacturing Method of Cover Strip>

[0099] As described above, the cover strip 10 can be manufactured using suitable materials and a suitable manufacturing process. Hereinafter, a preferred manufacturing method and the materials used in this method will be described in more detail.

[0100] First, an intermediate layer 2 is formed on at least one surface side of the substrate layer 1. The substrate layer 1 is preferably a film formed of an ester resin, an olefin resin, or the like. The intermediate layer 2 can be formed, for example, by extrusion lamination or dry lamination.

[0101] From the viewpoint of suppressing the peeling between the substrate layer 1 and the intermediate layer 2, a layer formed by an anchoring agent may exist between the substrate layer 1 and the intermediate layer 2, for example.

[0102] Next, a sealant layer forming liquid is applied to the surface of the intermediate layer 2 on the side opposite to the substrate layer 1 and then dried. For example, gravure coating can be used as the coating method.

[0103] The coating liquid for forming the sealant layer can typically be prepared by thoroughly mixing a resin (preferably a thermoplastic resin such as a (meth)acrylic resin or a styrene resin), an organic solvent, and additives such as inorganic particles or antistatic components as needed. In terms of obtaining coatability and desired film thickness, the viscosity of the coating liquid for forming the sealant layer at 28°C, measured using a vibratory viscometer according to JIS Z 8803, is preferably 2–10 mPa·s. The viscosity can be adjusted by adjusting the amount of solvent, using a suitable organic solvent, etc.

[0104] The organic solvents that can be used to prepare the coating liquid for forming the sealant layer are not particularly limited, but are preferably selected from esters such as ethyl acetate and butyl acetate; ketones such as methyl ethyl ketone, acetone, cyclohexanone, and methyl isobutyl ketone; aromatic hydrocarbons such as toluene and xylene; and aliphatic or alicyclic alcohols such as methanol, ethanol, n-propanol, isopropanol, and cyclohexanol.

[0105] In this embodiment, besides using a coating liquid of appropriate viscosity, it is preferable to optimize the drying conditions of the coating liquid applied to the surface of the intermediate layer 2 opposite to the substrate layer 1, so that the cover strip 10 with Spd and Sdq values ​​within an appropriate range can be manufactured. Specifically, the coating body formed by applying a sealant layer forming coating liquid of the above-mentioned viscosity to the intermediate layer is conveyed into a drying oven of 8 to 12 m in length with the oven temperature set to 70 to 100°C while the solvent is dried. At this time, the conveying speed is set to 140 to 200 m / min.

[0106] Although the details are not yet clear, due to the "uniformity" and "fluctuation" in solvent drying, it is speculated that by appropriately controlling the drying rate of the solvent and other drying conditions, in addition to controlling the viscosity of the coating liquid (especially related to diffusion ease), an uneven surface can be created on the surface of the sealant layer 3. The exposed surface of the dried sealant layer 3 is likely to have good surface properties that inhibit adhesion and component adhesion. Furthermore, it is speculated that by controlling the viscosity of the coating liquid containing particles (e.g., particles containing metal elements) when forming the sealant layer, in addition to controlling the viscosity of the coating liquid which is closely related to the ease of particle settling, the drying rate of the solvent can also be controlled. The values ​​of Spd and Sdq can also be adjusted by fixing the particles in a suitable settling state (or a suitable suspended state) in the final sealant layer 3.

[0107] <Electronic Component Packaging>

[0108] An electronic component package can be obtained from the cover tape 10 described above and the carrier tape that accommodates the electronic components in the recess. For this, refer to... Figure 2 Please provide an explanation.

[0109] exist Figure 2In this case, the electronic component packaging cover tape 10 is used as a cover material for a strip-shaped carrier tape 20 that is continuously provided with concave grooves 21 to match the shape of the electronic component.

[0110] Specifically, the cover tape 10 for electronic component packaging is joined (usually heat-sealed) to the surface of the carrier tape 20 in such a way that it covers the entire surface of the opening of the groove 21 of the carrier tape 20. Furthermore, the structure obtained by joining the cover tape 10 for electronic component packaging with the carrier tape 20 will be referred to as the electronic component packaging body 100 below.

[0111] The electronic component package 100 can be manufactured, for example, by following these steps.

[0112] First, electronic components are housed in the groove 21 of the carrier tape 20.

[0113] Then, the electronic component packaging cover tape 10 is bonded to the surface of the carrier tape 20 by heat sealing, so as to cover the entire surface of the opening of the groove 21 of the carrier tape 20. At this time, the sealant layer 3 in the electronic component packaging cover tape 10 is brought into contact with the carrier tape 20 (i.e., the sealant layer 3 in the electronic component packaging cover tape 10 is brought into contact with the carrier tape 20). Figure 2 The "back" of the electronic component packaging cover 10 is heat-sealed as a sealing layer 3.

[0114] As long as the cover tape 10 for electronic component packaging is securely and fully bonded to the carrier tape 20, there are no particular limitations on the specific method or conditions of heat sealing. Typically, a known heat sealing machine can be used, within a temperature range of 100–240°C, a load of 0.1–10 kgf, and a time range of 0.0001–1 second.

[0115] Thus, a structure (electronic component package 100) is obtained that seals and houses electronic components.

[0116] The structure (electronic component package 100) is, for example, wound on a reel and stored until the electronic component is used. Alternatively, there are cases where the reel with the electronic component package 100 wound on it is transported to a remote location by sea or air.

[0117] The scroll can be made of materials such as metal, paper, or plastic.

[0118] When using the electronic component, peel the cover tape 10 of the electronic component packaging from the carrier tape 20 and remove the contained electronic component.

[0119] There are no particular limitations on the electronic components housed within the electronic component package 100. Examples include semiconductor chips, transistors, diodes, capacitors, piezoelectric elements, optical elements, LED-related components, connectors, electrodes, and other components used in the manufacture of electrical / electronic equipment.

[0120] The embodiments of the present invention have been described above, but these are merely examples, and various configurations other than those described above are possible. Furthermore, the present invention is not limited to the above embodiments, and modifications and alterations within the scope of achieving the objectives of the present invention are included in the present invention.

[0121] Example

[0122] The embodiments and comparative examples of the present invention will be described in detail below. For the sake of caution, it should be noted beforehand that the present invention is not limited to the embodiments.

[0123] <Example 1>

[0124] The cover tape was manufactured using the following steps.

[0125] (1) As the substrate layer, a biaxially stretched polyester film (Toyobo Co., Ltd. "E7415") with a film thickness of 25 μm was prepared. On this single side, a low-density polyethylene (Sumitomo Chemical Co., Ltd. "SMIKASEN L705") with a thickness of 20 μm was formed by extrusion lamination at an extrusion temperature of 300°C, thus providing an interlayer. A laminated film was thus obtained.

[0126] (2) As a non-volatile component, a coating solution was prepared by uniformly dispersing or dissolving in toluene a mixture of 60% by mass of antimony-doped tin oxide (Mitsubishi Materials Corporation's "T-1", with an average particle size of approximately 20 nm) and 40% by mass of poly(meth)acrylic acid derivative (DIC Corporation's "A450A"). The amount of solvent used was adjusted to achieve a viscosity of 6 mPa·s at 28°C.

[0127] (3) A coated body was obtained by applying the above-mentioned coating liquid to the surface side of the laminated film where the intermediate layer is formed by gravure coating. The temperature of the coating liquid before coating was 28°C. Subsequently, the coated body was conveyed into a drying oven of approximately 10m in length with the oven temperature set at 85°C while the solvent was dried. The conveying speed was set to 180m / min (i.e., the coated body was heated in the drying oven for 10m / (180m / min) = 1 / 18 minutes = approximately 3.3 seconds while being conveyed).

[0128] Adjust the coating amount of the coating liquid until the dry film thickness of the sealant layer is 0.5 μm.

[0129] <Example 2>

[0130] The cover tape was manufactured using the following steps.

[0131] (1) As the substrate layer, a biaxially stretched polyester film (Toyobo Co., Ltd. "E7415") with a film thickness of 25 μm was prepared. On this single side, a low-density polyethylene (Sumitomo Chemical Co., Ltd. "SMIKASEN L705") with a thickness of 20 μm was formed by extrusion lamination at an extrusion temperature of 300°C, thus providing an interlayer. A laminated film was thus obtained.

[0132] (2) As a non-volatile component, a coating liquid was prepared by uniformly dispersing or dissolving in toluene the following components: 60% by mass of antimony-doped tin oxide (“T-1” manufactured by Mitsubishi Materials Corporation), 24% by mass of poly(meth)acrylic acid derivative (“A450A” manufactured by DIC Corporation), and 16% by mass of styrene-butadiene copolymer (“Taftec H1517” manufactured by Asahi Kasei Corporation). The amount of solvent used was adjusted to achieve a viscosity of 4 mPa·s at 28°C.

[0133] (3) A coated body was obtained by applying the above-mentioned coating liquid to the surface side of the laminated film where the intermediate layer is formed by gravure coating. The temperature of the coating liquid before coating was 28°C. Subsequently, the coated body was conveyed into a drying oven of approximately 10m in length with the oven temperature set at 85°C while the solvent was dried. The conveying speed was set to 180m / min (i.e., the coated body was heated in the drying oven for 10m / (180m / min) = 1 / 18 minutes = approximately 3.3 seconds while being conveyed).

[0134] Adjust the coating amount of the coating liquid until the dry film thickness of the sealant layer is 0.2 μm.

[0135] <Example 3>

[0136] The cover tape was manufactured using the following steps.

[0137] (1) As the substrate layer, a biaxially stretched polyester film (Toyobo Co., Ltd. "E7415") with a film thickness of 25 μm was prepared. On this single side, a low-density polyethylene (Sumitomo Chemical Co., Ltd. "SMIKASEN L705") with a thickness of 20 μm was formed by extrusion lamination at an extrusion temperature of 300°C, thus providing an interlayer. A laminated film was thus obtained.

[0138] (2) As a non-volatile component, a coating solution was prepared by uniformly dispersing or dissolving in toluene the following components: 60% by mass of antimony-doped tin oxide (“T-1” manufactured by Mitsubishi Materials Corporation), 24% by mass of poly(meth)acrylic acid derivative (“A450A” manufactured by DIC Corporation), and 16% by mass of styrene-butadiene copolymer (“Taftec H1517” manufactured by Asahi Kasei Corporation) (styrene content (PS ratio): 43%, MFR (230℃, 2.16 kg): 3 g / 10 min). The amount of solvent used was adjusted to achieve a viscosity of 2.5 mPa·s at 28℃.

[0139] (3) A coated body was obtained by applying the above-mentioned coating liquid to the surface side of the laminated film where the intermediate layer is formed by gravure coating. The temperature of the coating liquid before coating was 28°C. Subsequently, the coated body was conveyed into a drying oven of approximately 10m in length with the oven temperature set at 85°C while the solvent was dried. The conveying speed was set to 180m / min (i.e., the coated body was heated in the drying oven for 10m / (180m / min) = 1 / 18 minutes = approximately 3.3 seconds while being conveyed).

[0140] Adjust the coating amount of the coating liquid until the dry film thickness of the sealant layer is 0.2 μm.

[0141] <Comparative Example 1>

[0142] The cover tape was manufactured using the following steps.

[0143] (1) As the substrate layer, a biaxially stretched polyester film (Toyobo Co., Ltd. "E7415") with a film thickness of 25 μm was prepared. On this single side, a low-density polyethylene (Sumitomo Chemical Co., Ltd. "SMIKASEN L705") with a thickness of 20 μm was formed by extrusion lamination at an extrusion temperature of 300°C, thus providing an interlayer. A laminated film was thus obtained.

[0144] (2) As a non-volatile component, a coating solution was prepared by uniformly dispersing or dissolving in toluene the following components: 60% by mass of antimony-doped tin oxide (“T-1” manufactured by Mitsubishi Materials Corporation), 24% by mass of poly(meth)acrylic acid derivative (“A450A” manufactured by DIC Corporation), and 16% by mass of styrene-butadiene copolymer (“Taftec H1517” manufactured by Asahi Kasei Corporation) (styrene content (PS ratio): 43%, MFR (230℃, 2.16 kg): 3 g / 10 min). The amount of solvent used was adjusted to achieve a viscosity of 1.5 mPa·s at 28℃.

[0145] (3) A coated body was obtained by applying the above-mentioned coating liquid to the surface side of the laminated film where the intermediate layer is formed by gravure coating. The temperature of the coating liquid before coating was 28°C. Subsequently, the coated body was conveyed into a drying oven of approximately 10m in length with the oven temperature set at 85°C while the solvent was dried. The conveying speed was set to 180m / min (i.e., the coated body was heated in the drying oven for 10m / (180m / min) = 1 / 18 minutes = approximately 3.3 seconds while being conveyed).

[0146] Adjust the coating amount of the coating liquid until the dry film thickness of the sealant layer is 0.2 μm.

[0147] <Comparative Example 2>

[0148] The cover tape was manufactured using the following steps.

[0149] (1) As the substrate layer, a biaxially stretched polyester film (Toyobo Co., Ltd. "E7415") with a film thickness of 25 μm was prepared. On this single side, a low-density polyethylene (Sumitomo Chemical Co., Ltd. "SMIKASEN L705") with a thickness of 20 μm was formed by extrusion lamination at an extrusion temperature of 300°C, thus providing an interlayer. A laminated film was thus obtained.

[0150] (2) On the intermediate layer of the film, a melt mixture of 90% by mass of ethylene-vinyl acetate copolymer (Ultrasen 537 manufactured by Tosoh Corporation, with a vinyl acetate content of 6% by mass) and 10% by mass of tackifier (Arakawa Chemical Industries, Ltd., "Arkon P-100") was extruded onto the surface of the intermediate layer by extrusion molding at an extrusion temperature of 280°C to form a film with a thickness of 10 μm. Immediately afterwards, a cooling roller with protrusions having a surface roughness of 5.5 μm was used from the sealant layer side, and a silicone rubber pressure roller was used from the substrate layer side. The rollers were rotated while being clamped at a pressure of 0.2 MPa, thereby roughening the surface of the sealant layer. At this time, the temperature of the cooling roller was set to 20°C.

[0151] <Comparative Example 3>

[0152] The cover tape was manufactured using the following steps.

[0153] (1) As the substrate layer, a biaxially stretched polyester film (Toyobo Co., Ltd. "E7415") with a film thickness of 25 μm was prepared. On this single side, a low-density polyethylene (Sumitomo Chemical Co., Ltd. "SMIKASEN L705") with a thickness of 20 μm was extruded and laminated at an extrusion temperature of 300°C to serve as the intermediate layer.

[0154] (2) On the intermediate layer of the film, a melt mixture of 90% by mass of ethylene-vinyl acetate copolymer (Ultrasen 537 manufactured by Tosoh Corporation, with a vinyl acetate content of 6% by mass) and 10% by mass of tackifier (Arakawa Chemical Industries, Ltd., "Arkon P-100") was extruded onto the surface of the intermediate layer by extrusion molding at an extrusion temperature of 280°C to form a film with a thickness of 10 μm. Immediately afterwards, a cooling roller with protrusions having a surface roughness of 7.0 μm was used from the sealant layer side, and a silicone rubber pressure roller was used from the substrate layer side. The rollers were rotated while clamped at a pressure of 0.2 MPa, thereby roughening the surface of the sealant layer. At this time, the temperature of the cooling roller was set to 20°C.

[0155] <Determination of Surface Properties of Sealant Layer>

[0156] The following parameters of the (exposed) sealant layers in the above-described embodiments and comparative examples were measured using a Keyence Corporation VK-X3000 laser microscope. The software included with the apparatus was used for analysis.

[0157] • Arithmetic mean height Sa as defined in ISO 25178

[0158] The peak density Spd as defined in ISO 25178

[0159] • The root mean square slope Sdq as defined in ISO 25178

[0160] <Evaluation: Adhesion>

[0161] The cover strips of each embodiment and comparative example were cut into pieces with a width of 5.4 mm and a length of 500 m. Then, the cut cover strips were wound onto a spool without gaps.

[0162] The cover tape wound on the aforementioned roll was placed in an environment of 65°C for 24 hours.

[0163] After placement, the reel with the cover tape wound on it is held vertically and slowly rotated in the opposite direction to the direction of winding the cover tape. At this point, it is determined whether the wound cover tape can be wound out by its own weight, and how much force is required to wound it out if it cannot be wound out by its own weight. This is used to evaluate the adhesion strength (degree of bonding) between the surface and back of the cover tape. Specifically, the evaluation was carried out according to the following criteria.

[0164] • Able to roll out the cover strap under its own weight: Excellent.

[0165] • The cap tapes are slightly tightly sealed together, making it impossible to roll them out by their own weight. However, they can be easily unsealed by gently shaking them by hand: Good.

[0166] • The cover tapes are tightly sealed to each other, and the seal will not come apart even if the cover tapes are gently shaken by hand, and cannot be rolled out: poor.

[0167] <Evaluation: Component Attachment>

[0168] The adhesion of the components was evaluated by conducting the following adhesion test on the metal sheet of the simulated electronic components.

[0169] (1) The cover strips obtained in the examples and comparative examples were cut to an appropriate size and attached to a microscope slide with the sealant layer surface facing upwards. A test piece was prepared by placing 20 metal sheets (0.4 mm in length × 0.8 mm in width × 0.4 mm in thickness) on the sealant layer. The metal sheets were obtained by cutting nickel using a precision cutter.

[0170] (2) The obtained test pieces were left to stand for 24 hours at 60℃ and 95%RH, and then left to stand for 24 hours at room temperature and humidity.

[0171] (3) Following (2) above, the test piece was secured with double-sided tape on a vortex mixer while the slide was flipped. Then, the vortex mixer was set to 1500 rpm, and the test piece was vibrated for 20 seconds.

[0172] (Since there was no dedicated device for applying vibration, a vortex mixer originally used for stirring liquids was used to apply vibration to the test piece.)

[0173] (4) After (3) above, the adhesion ratio was calculated based on the number of metal sheets attached to the surface of the sealant layer.

[0174] The above measurement and evaluation results are summarized in the table below.

[0175] [Table 1]

[0176] Sa(μm) 0.262 0.166 0.131 0.102 0.666 0.84 <![CDATA[Spd( / mm 2 )]]> 734388 489579 376210 213974 204283 153019 Sdq 0.208 0.158 0.141 0.096 0.316 0.595 Adhesion Very good Very good good Difference Difference Difference Component adhesion rate (%) 0 0 0 20 25 40

[0177] As shown in the table above, the peak density Spd at the exposed surface of the sealant layer is 3 × 10⁻⁶. 5 ~1×10 6 / mm 2 Within the range, and the root mean square slope Sdq of the exposed surface of the sealant layer is 1.0 × 10⁻⁶. -2 ~5.0×10 -1 In the evaluation of the cover tapes in Examples 1 to 3, adhesion and component adhesion were suppressed.

[0178] In contrast, when Spd is less than 3×10 5 Comparative Examples 1 and 2: Spd is less than 3 × 10 5 And Sdq is greater than 5×10 -1 In Comparative Example 3, the adhesion evaluation result was poor, and the component was stuck together.

[0179] Incidentally, in the aforementioned adhesion evaluation, adhesion was suppressed even under the stringent evaluation condition of being placed at 65°C for 24 hours. This favorable result was achieved by focusing on and optimizing indicators such as Spd or Sdq of the sealant layer.

[0180] This application claims priority based on Japanese Patent Application No. 2023-048726, filed on March 24, 2023, the entire contents of which are incorporated herein by reference.

[0181] Explanation of reference numerals in the attached figures

[0182] 1: Substrate layer.

[0183] 2: Intermediate layer.

[0184] 3: Sealant layer.

[0185] 10: Cover strap.

[0186] 20: Carrier tape.

[0187] 21: Groove.

[0188] 100: Packaging for electronic components.

Claims

1. A cover strip for packaging electronic components, comprising a substrate layer and a sealant layer disposed on one side of the substrate layer, wherein, The surface of the sealant layer opposite to the substrate layer becomes the exposed surface. The peak density Spd defined in ISO 25178 of the exposed surface is 3 x 10 5 ~ 1 x 10 6 / mm 2 , The root mean square slope Sdq defined in ISO 25178 of the exposed surface is 1.0 x 10 -2 ~ 5.0 x 10 -1 , The arithmetic mean height Sa of the exposed surface, as defined in ISO 25178, is 0.05–0.5 μm.

2. The cover strip according to claim 1, wherein, The sealant layer contains inorganic particles.

3. The cover strip according to claim 1, wherein, The sealant layer contains one or both of styrene-based resin and (meth)acrylic resin.

4. The cover strip according to claim 1, wherein, The substrate layer contains polyester.

5. The cover strip according to claim 1, wherein, The cover strip has an intermediate layer between the substrate layer and the sealant layer.

6. The cover strip according to claim 5, wherein, The intermediate layer contains polyethylene resin.

7. An electronic component packaging body, wherein, The electronic component package includes a carrier strap that accommodates the electronic component in a recess and a cover strap as described in claim 1. The sealant layer is bonded to the carrier tape to seal the electronic component.

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