WO2021187523A1

WO2021187523A1 - Cover tape for packaging electronic component and package

Info

Publication number: WO2021187523A1
Application number: PCT/JP2021/010797
Authority: WO
Inventors: 峻平柳澤; 保則長塚; 真邦井上
Original assignee: 大日本印刷株式会社
Priority date: 2020-03-17
Filing date: 2021-03-17
Publication date: 2021-09-23
Also published as: TW202200378A

Abstract

The present disclosure provides a cover tape for packaging an electronic component, comprising: a base material layer; a heat-seal layer disposed on one face side of the base material layer; and an antistatic layer disposed on a face side of the base material layer opposite to the face on the heat-seal layer side. The cover tape for packaging an electronic component is characterized in that the face on the side on which the antistatic layer is disposed has a surface resistivity of 1 × 10¹⁰Ω/□ or less, the heat-seal layer comprises an antistatic agent, and the cover tape for packaging an electronic component has a light transmission rate of not less than 80% at an incident angle of 40°.

Description

Cover tape and packaging for electronic component packaging

This disclosure relates to a cover tape for packaging electronic components and a packaging body using the same.

In recent years, electronic components such as ICs, resistors, transistors, diodes, capacitors, and piezoelectric element registers have been taped and packaged for surface mounting. In taping packaging, after storing electronic parts in a carrier tape having a plurality of storage portions for storing electronic parts, the carrier tape is heat-sealed with a cover tape to obtain a package for storing and transporting the electronic parts. When mounting electronic components, the cover tape is peeled off from the carrier tape, and the electronic components are automatically taken out and surface-mounted on the substrate. The cover tape is also called a top tape.

In taping packaging, static electricity is generated by friction or contact of an electronic component with a carrier tape or cover tape, and the static electricity may cause deterioration or electrostatic destruction of the electronic component.
In addition, static electricity may be generated by peeling the cover tape from the carrier tape during mounting, and electronic components may adhere to the cover tape, making it impossible to take out the electronic components normally. Therefore, the carrier tape and the cover tape are required to have high antistatic properties.

In addition, in the unopened state of the taping package, defects in the electronic components that are the contents can be detected by visual observation or camera inspection from the top of the cover tape, and the code printed on the electronic components can be recognized. Is being done. Therefore, the cover tape is also required to have high transparency, and various cover tapes focusing on the transmittance have been proposed (for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2015-140200 Japanese Unexamined Patent Publication No. 2019-171577

Electronic components are becoming smaller and more difficult to check through the cover tape. Furthermore, in the process of mounting electronic components such as ICs, the position, orientation, and angle of the electronic components in the storage unit are confirmed by taking a picture from the top of the cover tape with a CCD (Charge Coupled Device) camera or the like and analyzing the image. A method of performing a mounting process is being implemented. As described above, the cover tape is required to be further improved in visibility due to the miniaturization of electronic components and the request for confirmation by a CCD camera.

In an actual camera inspection, the electronic components in the storage portion of the package may be photographed through the cover tape not from the vertical direction of the cover tape surface but from an oblique direction at an angle with respect to the vertical direction. .. The present inventors have found that in a package using the above-mentioned conventional cover tape, the visibility of electronic components may deteriorate when the inside of the storage portion is checked from an oblique direction through the cover tape. bottom.

The present disclosure has been made in view of the above problems, and when the electronic component is photographed through the cover tape (particularly, when the electronic component is photographed from an oblique direction), the electronic component has excellent visibility and is highly charged. An object of the present invention is to provide a cover tape for packaging electronic components having preventive performance.

In one embodiment of the present disclosure, the base material layer, the heat seal layer arranged on one surface side of the base material layer, and the surface side of the base material layer opposite to the surface of the base material layer on the heat seal layer side. A cover tape for packaging electronic components having an antistatic layer to be arranged, the surface resistivity of the surface on the side on which the antistatic layer is arranged is 1 × 10 ¹⁰ Ω / □ or less, and the heat Provided is a cover tape for electronic component packaging, wherein the seal layer contains an antistatic agent, and the cover tape for packaging electronic components has a light transmittance of 80% or more at an incident angle of 40 degrees.

In one embodiment of the present disclosure, the base material layer, the heat seal layer arranged on one surface side of the base material layer, and the surface side of the base material layer opposite to the surface of the base material layer on the heat seal layer side. A cover tape for packaging electronic components having an antistatic layer to be arranged, the surface resistivity of the surface on the side on which the antistatic layer is arranged is 1 × 10 ¹⁰ Ω / □ or less, and the heat The cover tape for electronic component packaging, wherein the seal layer contains an antistatic agent, provides a cover tape for electronic component packaging, which has a light absorption rate of 10% or less at an incident angle of 40 degrees.

In one embodiment of the present disclosure, the carrier tape having a plurality of storage portions for storing electronic components, the electronic components stored in the storage portions, and the electronic component packaging arranged so as to cover the storage portions. Provided is a packaging body comprising a cover tape for use.

The cover tape for packaging electronic components of the present disclosure has high antistatic performance, and also has excellent visibility of electronic components when observing or photographing electronic components through the cover tape.

It is the schematic cross-sectional view which illustrates the cover tape for electronic component packaging of this disclosure. It is a schematic plan view and a cross-sectional view which exemplify the package body of this disclosure. It is the schematic cross-sectional view which illustrates the cover tape for electronic component packaging of this disclosure. It is schematic cross-sectional view in the apparatus explaining the large variable angle integrating sphere unit for V-670.

An embodiment of the present disclosure will be described below with reference to drawings and the like. However, the present disclosure can be implemented in many different embodiments and is not construed as limited to the description of the embodiments illustrated below. Further, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the actual form, but this is merely an example and the interpretation of the present disclosure is limited. It's not something to do. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures may be designated by the same reference numerals, and detailed description thereof may be omitted as appropriate.

In the present specification, when expressing the mode of arranging another member on one member, when it is simply described as "above" or "below", it is in contact with a certain member unless otherwise specified. Including the case where another member is arranged directly above or directly below, and the case where another member is arranged above or below a certain member via another member. Further, in the present specification, when expressing the mode of arranging another member on the surface of a certain member, when simply expressing "on the surface side" or "on the surface", unless otherwise specified, the certain member is used. It includes both the case where another member is arranged directly above or directly below the member so as to be in contact with each other, and the case where another member is arranged above or below one member via another member.

As mentioned above, various cover tapes focusing on transmittance have been proposed. However, the present inventors do not have a problem with the conventional cover tape in the case of photographing the electronic component through the cover tape in the package from a direction perpendicular to the surface of the cover tape in the camera inspection. However, it was found that the visibility may deteriorate when the image is taken from an oblique direction. And this phenomenon is that the conventional cover tape has a high transmittance of light at an incident angle of 0 degrees, but the transmittance of light having an incident angle larger than 0 degrees (for example, 40 degrees) may not be sufficiently high. It was found that it was caused.

In the conventional cover tape, in order to give the antistatic layer sufficient antistatic performance, the film thickness of the antistatic layer may be increased, and as a result, the transmittance may decrease. In addition, the absorption rate may be high. Further, an antistatic agent (for example, conductive particles) may be added to the heat seal layer in order to give the cover tape sufficient antistatic performance, but the heat seal layer is a film to ensure the seal strength. The thickness is usually set to be relatively thick, 1 μm or more, and as a result, the content of the antistatic agent increases, the heat seal layer becomes colored or internally diffused, and the transmittance may decrease. .. In addition, the absorption rate may be high. The present inventors have stated that such a tendency of decreasing the transmittance and increasing the absorption rate becomes more remarkable because the optical path length in the cover tape becomes longer when the incident angle is larger than 0 degrees. I found out. Therefore, the conventional cover tape does not have both a transmittance or an absorption rate that does not cause deterioration of visibility from an oblique direction and an excellent antistatic performance.

Therefore, the present inventors have provided an antistatic layer so that the surface resistivity is equal to or less than a specific value, and added an antistatic agent to the heat seal layer to improve the antistatic performance of the cover tape as a whole. Furthermore, if the cover tape has a light transmittance of 80% or more at an incident angle of 40 degrees, it has excellent antistatic performance, and the visibility of electronic components deteriorates when a camera inspection or the like is performed from an oblique direction. It was found that it can suppress.

Further, the present inventors have provided an antistatic layer so that the surface resistivity is equal to or less than a specific value, and added an antistatic agent to the heat seal layer to improve the antistatic performance of the cover tape as a whole. Furthermore, if the cover tape has a light absorption rate of 10% or less at an incident angle of 40 degrees, it has excellent antistatic performance, and the visibility of electronic components deteriorates when a camera inspection or the like is performed from an oblique direction. It was found that it can suppress.

Here, when light is incident from an angle direction larger than the incident angle of 40 degrees, the reflection component at the surface of the cover tape and the internal layer interface tends to be high. Similarly, when a camera inspection or the like is performed from an angle direction larger than an incident angle of 40 degrees, the amount of reflected light detected increases, which is generally not preferable as a camera arrangement in the inspection. Therefore, the inspection camera or the like is usually arranged at an angle of 40 degrees or less with respect to the vertical direction of the film surface, and in such an angle range, deterioration of visibility due to reflected light is unlikely to occur.

In recent years, the structure of electronic components has tended to become more complicated, and defects in components cannot be accurately detected only by imaging from 0 degrees (directly above), so inspection that also includes imaging from an oblique direction has become important. ing. In addition, since the inspection is performed at high speed, even if the imaging is set at 0 degrees, it may deviate from 0 degrees.
Hereinafter, the cover tape for packaging electronic components and the packaging body of the present disclosure will be described in detail.

A. Cover tape for packaging electronic components (first and second embodiments)
The cover tape for packaging electronic components of the first embodiment in the present disclosure includes a base material layer, a heat seal layer arranged on one surface side of the base material layer, and the heat seal layer side of the base material layer. A cover tape for packaging electronic components having an antistatic layer arranged on the surface opposite to the surface, and the surface resistivity of the surface on the side on which the antistatic layer is arranged is 1 × 10 ¹⁰ Ω. / □ or less, the heat seal layer contains an antistatic agent, and the cover tape for packaging electronic components is characterized in that the light transmittance at an incident angle of 40 degrees is 80% or more.

The cover tape for packaging electronic components of the second embodiment in the present disclosure includes a base material layer, a heat seal layer arranged on one surface side of the base material layer, and the heat seal layer side of the base material layer. A cover tape for packaging electronic components having an antistatic layer arranged on the surface opposite to the surface, and the surface resistivity of the surface on the side on which the antistatic layer is arranged is 1 × 10 ¹⁰ Ω. / □ or less, the heat seal layer contains an antistatic agent, and the cover tape for packaging electronic components is characterized in that the light absorption rate at an incident angle of 40 degrees is 10% or less.

In this specification, "cover tape for packaging electronic components" may be simply referred to as "cover tape".

The cover tapes of the first embodiment and the second embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the cover tapes of the first embodiment and the second embodiment of the present disclosure. As shown in FIG. 1, the cover tape 1 of the present disclosure includes a base material layer 2, a heat seal layer 3 arranged on one surface side of the base material layer 2, and a heat seal layer 3 side of the base material layer 2. It has an antistatic layer 4 arranged on the surface side opposite to the surface of the surface.

2 (a) and 2 (b) are schematic plan views and cross-sectional views showing an example of a package using the cover tape for packaging electronic components of the first embodiment and the second embodiment of the present disclosure. b) is a cross-sectional view taken along the line AA of FIG. 2 (a). As shown in FIGS. 2A and 2B, the package 10 stores the carrier tape 11 having a plurality of storage portions 12 for storing the electronic components 13, the electronic components 13 stored in the storage portions 12, and the electronic components 13. A cover tape 1 arranged so as to cover the portion 12 is provided. The cover tape 1 is heat-sealed on the carrier tape 11, and heat-sealing portions 3h are provided on both ends of the heat-sealing layer 3 of the cover tape 1 in a line shape with a predetermined width.
Further, in the package 10, the carrier tape 11 can have a feed hole 14.

In the configuration of the cover tapes of the first embodiment and the second embodiment, for example, an antistatic layer having high antistatic performance and a thin antistatic layer is provided on one surface of the base material, which is opposite to the antistatic layer side of the base material. It can be obtained by providing a heat seal layer containing an antistatic agent on the side, which is less likely to cause coloring.
Hereinafter, each configuration of the cover tape of the first embodiment and the second embodiment of the present disclosure will be described.

I. Antistatic layer The antistatic layer in the present disclosure is a layer arranged on the surface opposite to the surface of the base material layer on the heat seal layer side to prevent the cover tape from being charged. By having the antistatic layer, it is possible to prevent the generation of static electricity due to contact with other surfaces, and to prevent the static electricity from being charged and adhering dust, dust, etc. to the surface of the cover tape.

The surface resistivity of the surface of the cover tape on the side where the antistatic layer is arranged in the present disclosure is 1 × 10 ¹⁰ Ω / □ or less, preferably 1 × 10 ⁹ Ω / □ or less.

In the present disclosure, the "surface on the side where the antistatic layer of the cover tape is arranged" is not particularly limited, but is usually the surface of the antistatic layer. The surface resistivity is a value performed under the following test conditions using High Resta UP MCP-HT450 manufactured by Mitsubishi Chemical Analytech Co., Ltd.

(Test conditions)
・ Probe: UA probe ・ Applicable voltage: 10 ¹⁰ Ω / less than □ 10 V
10 ¹⁰ to 10 ¹² Ω / □ 500 V
10 ¹³ Ω / □ or more 1000 V
-Measurement point: Central part of sample-Measurement value: Measure 5 points so that the measurement points do not overlap, and adopt the average value-One measurement time: Adopt the display after 10 seconds-Sample storage before measurement: 25 ° C 40 Storage / measurement environment for 24 hours or more in% RH environment: 25 ± 2 ° C, 40 ± 5% RH environment

It is preferable that the surface resistivity of the surface of the cover tape on the side where the antistatic layer is arranged is lower than the surface resistivity of the surface on the side where the heat seal layer is arranged. If an attempt is made to lower the surface resistivity of the surface on the side on which the heat seal layer is arranged, the visibility may be lowered and the heat sealability may be lowered. In order to suppress the static charge when the cover tape is peeled off in the mounting process, it is important to impart antistatic properties to the entire front and back surfaces of the cover tape. Therefore, by lowering the surface resistivity of the surface of the cover tape on the side on which the antistatic layer is arranged, it is possible to suppress a decrease in visibility and a decrease in heat sealability.

The antistatic layer in the present disclosure is not particularly limited, and examples thereof include a layer containing a conductive polymer and a layer containing a polymer-type surfactant. Of these, two aspects, a first antistatic layer and a second antistatic layer, which will be described later, are preferable. In particular, the first antistatic layer (layer containing a conductive polymer), which will be described later, is preferable because the surface resistivity can be obtained even if the thickness is small. Since the antistatic layer is thin, the light transmittance of the cover tape at an incident angle of 40 degrees can be improved. Further, since the antistatic layer is thin, the light absorption rate of the cover tape at an incident angle of 40 degrees can be reduced.

The thickness of the antistatic layer is preferably thinner than the thickness of the heat seal layer described later. Specifically, the thickness of the heat seal layer: the thickness of the antistatic layer = 1: 0.001 to 1: 0.5 is preferable.

(1) First Antistatic Layer The first antistatic layer in the present disclosure contains a conductive polymer. Since the first antistatic layer has a conductive polymer, the surface resistance of the antistatic layer is reduced. In the second antistatic layer, which will be described later, the quaternary ammonium salt has a strong affinity for water, attracts water molecules, and forms a film of water on the surface of the antistatic layer to reduce the surface resistance. On the other hand, the conductive polymer in the first antistatic layer itself exhibits conductivity. Therefore, even if the antistatic layer is thin, the surface resistance ^{can be easily reduced to 1 × 10 10} Ω / □ or less.

(A) Conductive polymer Examples of the conductive polymer include polythiophene, polyaniline, polypyrrole, polyacetylene, polyparaphenylene, polyphenylene vinylene, polyvinylcarbazole and the like.
Among them, polythiophene is preferable as the conductive polymer. As the polythiophene, for example, PEDOT / PSS (poly (3,4-ethylenedioxythiophene / polystyrene sulfonic acid)) is preferably used.

(B) Crosslinked resin The first antistatic layer in the present disclosure has a crosslinked resin containing an acrylic main chain and a crosslinked structure in addition to the above conductive polymer, and the crosslinked structure is −C (= O) OC. _{It is preferable to have 2} H ₄ NH- or -C (OH) CH ₂ OC (= O)-. Such a first antistatic layer is formed of an antistatic material having a conductive polymer, a first crosslinkable acrylic polymer having a carboxylate anionic group, and a first polyfunctional curing agent. NS.

The crosslinked structure in the crosslinked resin contained in the first antistatic layer is composed of a crosslinkable functional group (carboxylate anion (-COO-) and other crosslinkable functional groups) of the first crosslinkable acrylic polymer described later. , A structure in which a first polyfunctional curing agent is bonded, and has -C (= O) OC ₂ H ₄ NH- or -C (OH) CH ₂ OC (= O)-.

(C) Thickness The thickness of the first antistatic layer is a value required for the surface resistivity of the first antistatic layer to satisfy the above values, and is, for example, 0.02 μm or more, preferably 0. It is 05 μm or more. On the other hand, from the viewpoint of permeability, the thinner one is preferable, and for example, it is 0.50 μm or less, preferably 0.25 μm or less.

(2) Second Antistatic Layer The second antistatic layer has an acrylic main chain, a side chain containing a quaternary ammonium salt, and a crosslinked resin containing a crosslinked structure, and the crosslinked structure is -NHC (= O). ) O-, -NHC (= O)-or-C (= O) OC ₂ H ₄ NH-. The second antistatic layer is formed from an antistatic material having a second crosslinkable acrylic polymer containing a crosslinkable functional group and a group having a quaternary ammonium salt, and a second polyfunctional curing agent. NS.

(A) Crosslinked resin The second antistatic layer in the present disclosure has a crosslinked resin which is a crosslinked resin, and the crosslinked resin contains an acrylic main chain, a side chain containing a quaternary ammonium salt, and a crosslinked structure.
The quaternary ammonium salt has a function as a hydrophilic part of the surfactant, and the quaternary ammonium salt oriented toward the surface side of the antistatic layer has a strong affinity with water, attracts water molecules, and attracts water molecules to the surface of the antistatic layer. The surface resistance is reduced by forming a film of.

Examples of the quaternary ammonium salt contained in the crosslinked resin include those represented by the following formula (1).
^{_{^{-N + R 3 A - (1}}} )
(In the formula, R is an organic group that is the same or different from each other independently.)
R is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 2 carbon atoms from the viewpoint of surface orientation of the quaternary ammonium salt. The quaternary ammonium salt represented by the above formula (1) is bonded to an acrylic chain which is a main chain via a divalent hydrocarbon group which may contain oxygen and nitrogen. A ^- is any anion, from the viewpoint of improving surface hydrophilicity, halogen anion ^{^{^{(F -, Cl -, Br}}} -, I -) or substituted or unsubstituted alkyl sulfate anion having from 1 to 6 carbon atoms preferably, in particular Cl ^-, or a substituted or unsubstituted alkyl sulfate anion having from 1 to 3 carbon atoms it is more preferred.

The divalent hydrocarbon group is -X (CH ₂ ) _n- (in the formula, n is an integer of 1 to 6 and X is an amide group (-C (= O) NH-) or an ester group (in the formula). -C (= O) O-), and the carbon atom of the amide group or ester group is bonded to the acrylic chain which is the main chain) is preferable.
The content of the quaternary ammonium salt contained in the antistatic layer can be a value necessary for the surface resistivity of the antistatic layer in the present disclosure to fall within the numerical range described later.

The crosslinked structure is a structure in which the crosslinkable functional group of the second crosslinkable acrylic polymer described later and the second polyfunctional curing agent are bonded, and -NHC (= O) O-, -NHC (=). It has O)-or -C (= O) OC ₂ H ₄ NH-. The second antistatic layer has an acrylic chain as a main chain. As used herein, the term "acrylic chain" means a comprehensive term for an acrylic chain and a methacryl chain.

(B) Thickness The thickness of the second antistatic layer is a value required for the surface resistivity of the second antistatic layer to satisfy the above values, and is, for example, 0.05 μm or more, preferably 0.1 μm. That is all. On the other hand, from the viewpoint of permeability, it is preferably thin, for example, 0.5 μm or less, preferably 0.25 μm or less.

II. Base material layer The base material layer in the present disclosure is a layer that supports the above-mentioned antistatic layer and heat seal layer.
As the base material layer, various materials can be applied as long as it has mechanical strength to withstand external forces during storage and transportation, heat resistance to withstand manufacturing and taping packaging, and the like. For example, polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene terephthalate-isophthalate copolymers, terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymers, and polyamides such as nylon 6, nylon 66 and nylon 610. Examples thereof include polyolefins such as polyethylene, polypropylene, and polymethylpentene. Among them, polyesters such as polyethylene terephthalate and polyethylene naphthalate are preferably used because of their good cost and mechanical strength.

The thickness of the base material layer can be, for example, 2.5 μm or more and 300 μm or less, 6 μm or more and 100 μm or less, or 12 μm or more and 50 μm or less. If the thickness of the base material layer is too thick, the rigidity at the time of taping packaging becomes strong, which is disadvantageous in terms of handleability and cost. Further, if the thickness of the base material layer is too thin, the mechanical strength may be insufficient.

III. Heat-seal layer The heat-seal layer in the present disclosure is a layer arranged on the surface side of the base material layer opposite to the antistatic layer. When the package is manufactured using the cover tape of the present disclosure, the heat seal layer is heat-sealed against the carrier tape, so that the cover tape and the carrier tape are adhered to each other. In addition, the heat seal layer in the present disclosure contains an antistatic agent. In addition to arranging the antistatic layer on the surface side of the base material layer opposite to the heat seal layer, by adding an antistatic agent to the heat seal layer, the antistatic property of the cover tape as a whole is further improved. be able to.

The antistatic agent contained in the heat seal layer is not particularly limited, but it is preferable that the antistatic agent has low visible light absorption and is less likely to cause coloring. For example, glycerin fatty acid ester, polyglycerin fatty acid ester, sorbitan fatty acid ester, polyoxyethylene alkylphenyl ether, polyoxyalkylene alkyl ether (for example, polyoxyethylene alkyl ether), polyethylene glycol fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid alkanol. Examples thereof include nonionic surfactants such as amide. These may be used alone or in combination of two or more.

In the present disclosure, the surface resistivity of the surface of the cover tape on the side where the heat seal layer is arranged ^{is preferably 1 × 10 10} Ω / □ or more, and ^{more preferably 1 × 10 11} Ω / □ or more.
This is because the amount of the antistatic agent added can be reduced, and the light transmittance at the incident angle of 40 degrees of the cover tape can be improved. Further, it is possible to reduce the light absorption rate at an incident angle of 40 degrees of the cover tape. On the other hand, in order to obtain high antistatic properties of the cover tape as a whole, ^{it is preferably 1 × 10 14} Ω / □ or less, and ^{more preferably 5 × 10 13} Ω / □ or less.
The "face on the side where the heat seal layer of the cover tape is arranged" is usually the surface of the heat seal layer.

The surface resistivity of the heat seal layer is a value measured under the same test conditions as the surface resistivity of the surface on the side where the antistatic layer is arranged, which is described in "I. Antistatic layer" described above.

The heat seal layer has a thermoplastic resin, and the thermoplastic resin is any one of an ethylene-vinyl acetate-based copolymer, an acrylic resin, a polyester-based resin, a polyurethane resin, and a vinyl chloride-vinyl acetate copolymer. Alternatively, a resin containing these as a main component is preferable. Above all, it is preferable to contain an ethylene-vinyl acetate copolymer. When the heat seal layer contains an ethylene-vinyl acetate copolymer, the heat seal property for the carrier tape is improved. Therefore, it is possible to suppress the occurrence of unintended peeling during transportation, storage, and the like.

In the present disclosure, the ethylene-vinyl acetate-based copolymer is a copolymer containing at least an ethylene monomer unit and a vinyl acetate monomer unit. The ethylene monomer unit means a structural unit derived from an ethylene monomer, and the vinyl acetate monomer unit means a structural unit derived from a vinyl acetate monomer.

When the heat seal layer in the present disclosure contains an ethylene-vinyl acetate copolymer, it is preferable that it further contains a polyethylene resin. By blending the polyethylene resin, it is possible to reduce the surface tackiness while maintaining good heat sealability and suppress deterioration after being placed in a high humidity and heat environment.

Examples of the polyethylene resin include various types of polyethylene such as low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, and high-density polyethylene. Since they are superior from the viewpoint of dispersibility, low-density polyethylene (LDPE, (Density 0.910 to less than 0.930) and linear low density polyethylene (LLDPE, density 0.910 to 0.925) are preferably used.

Further, in the present disclosure, the classification of various polyethylenes refers to those defined in the former JIS K6748: 1995 and JIS K6890-1: 2000. The content of the polyethylene resin in the heat seal layer is preferably 10% by mass or more and 50% by mass or less, and more preferably 20% by mass or more and 40% by mass or less.

If necessary, the heat seal layer may contain additives such as a tackifier, an anti-blocking agent, a dispersant, a filler, a plasticizer, and a colorant.

The thickness of the heat seal layer can be, for example, 0.5 μm or more and 30 μm or less, preferably 1 μm or more and 20 μm or less. If the thickness of the heat seal layer is too thin, the sealability may be inferior, and a uniform film may not be obtained. If the heat seal layer is too thick, the transparency of the cover tape may decrease.

The surface roughness of the heat seal layer is based on JIS B 0601, and the arithmetic average roughness Ra is, for example, 0.2 μm ≦ Ra ≦ 1.2 μm, preferably 0.2 μm ≦ Ra ≦ 0.8 μm, more preferably 0.2 μm ≦ Ra ≦ 0.8 μm. 0.2 μm ≦ Ra ≦ 0.6 μm. The maximum height Rz is, for example, 2.0 μm ≦ Rz ≦ 10 μm, preferably 2.0 μm ≦ Rz ≦ 8.0 μm. If the surface roughness of the heat seal layer is too large, the transmittance may decrease due to the influence of interfacial reflection when the light incident on the incident angle of 40 degrees is transmitted through the tape.

The arithmetic mean roughness Ra and the maximum height Rz are values measured under the following test conditions using a small surface roughness measuring machine Surftest SJ-210 (manufactured by Mitutoyo Co., Ltd.).
(Test conditions)
・ Standard JIS B 0602-2001
・ Curve: R
・ Filter: GAUSS
・ Λc / λs: 0.8 / 2.5
・ Number of sections: × 5
・ Measurement speed 0.5 mm / s
・ Measure a total of 5 points and calculate the average value

IV. Cover Tape (1) First Embodiment The cover tape according to the first embodiment of the present disclosure has a light transmittance of 80% or more at an incident angle of 40 degrees. Above all, it is preferably 82% or more. The above-mentioned transmittance is the transmittance of light incident from an oblique direction of 40 degrees (that is, at an incident angle of 40 degrees) with respect to the vertical direction (incident angle of 0 degrees) of the surface of the cover tape on the antistatic layer side. It is a value measured under the following test conditions using an infrared spectrophotometer V-670, a large angle-variable integrating sphere unit for V-670, and a polarizer GPH-506 (Nippon Spectroscopy Co., Ltd.).

(Test conditions)
-Measurement wavelength range: 380 to 780 nm
-Measurement spectrum bandwidth: 5.0 nm
-Scanning speed: 400 nm / min
-Measurement wavelength interval: 1.0 nm
・ Inner diameter of integrating sphere: 150 mm in diameter
・ Ray incident angle: Transmittance (40 °)
-Transmittance (%): Calculates the average value of the measurement wavelength range

Further, the cover tape according to the first embodiment of the present disclosure preferably has a transmittance of 80% or more of light incident from the vertical direction (incident angle of 0 degrees) on the surface of the cover tape.

Regarding the transmittance of the cover tape, it is preferable that the variation (maximum value-minimum value) of the transmittance in the measurement wavelength range of 380 to 780 nm is 10% or less, preferably 5% or less. If the variation is within the above range, it is possible to select an inspection light source (color and wavelength) suitable for the type of electronic component or carrier tape without being affected by the coloring of the cover tape.

The cover tape according to the first embodiment of the present disclosure preferably has an absorption rate of light incident at an incident angle of 40 ° of preferably 10% or less, particularly preferably 5% or less. Further, it is preferable that the absorption rate of the incident light at an incident angle of 0 ° is 10% or less. The absorption rate at an incident angle of 0 ° and the absorption rate at an incident angle of 40 ° are values calculated in the same manner as in "(2) Second embodiment" described later.

(2) Second Embodiment The cover tape according to the second embodiment of the present disclosure has a light absorption rate of 10% or less at an incident angle of 40 degrees. Above all, it is preferably 5% or less. Further, it is preferable that the absorption rate of the incident light at an incident angle of 0 ° is 10% or less.

The absorption rate at an incident angle of 0 ° is a value calculated by the following formula. The reflectance (10 °) was determined by using the above-mentioned ultraviolet-visible near-infrared spectrophotometer V-670, a large variable-angle integrating sphere unit for V-670, and a polarizer GPH-506 (JASCO Corporation), and the above (test). Condition), it is the average value of the reflectance in the measurement wavelength range measured with the light incident angle of 10 °.
・ Absorption rate (0 °) (%) = 100- [Transmittance (0 °)]-[Reflectance (10 °)]

The absorption rate at an incident angle of 40 ° is a value calculated by the following formula. The reflectance (40 °) is an average value of the reflectances in the measurement wavelength range measured as a light incident angle of 40 ° under the above (test conditions).
-Calculated by absorption rate (40 °) (%) = 100- [transmittance (40 °)]-[reflectance (40 °)]

The large variable-angle integrating sphere unit for V-670 used for measuring the transmittance and reflectance has a large integrating sphere, and a detector (ultraviolet visible region: photoelectron doubling tube, near red) is provided above the integrating sphere. Outer region: PbS (lead sulfide)). As shown in FIG. 4, the large integrating sphere 40 of the variable angle large integrating sphere unit for V-670 has a spherical inner surface and is provided with a plurality of openings, and these openings are provided with a standard white plate 41 (BaSO ₄ ). Can be installed. An entrance opening is provided at a position where the measurement light is irradiated.

When measuring the transmittance at an incident angle of 0 °, as shown in the left figure of FIG. 4A, a cover tape 1 is installed at the position of the inlet opening O of the integrating sphere 40, and the incident angle is set to 0 °. Make a measurement. At this time, a standard white plate 41 is installed in the openings other than the entrance opening O. When measuring the transmittance at an incident angle of 40 °, rotate the integrating sphere 40 around the sample (cover tape) installation position from the integrating sphere position at an incident angle of 0 ° (left figure in FIG. 4A). , The transmittance at an incident angle of 40 ° is measured (right figure of FIG. 4A).

When measuring the reflectance of the incident angle 10 °, as shown in the left diagram of FIG. 4 (b), light enters from the inlet opening O ₁₀ as the incident angle becomes 10 °, the cover tape The measurement is performed by reflecting it on. At this time, the inlet opening _{O 40} installing the standard white plate 41. When measuring the reflectance at an incident angle of 40 °, the integrating sphere 40 is rotated around the cover tape installation position from the position of the integrating sphere at an incident angle of 10 ° (left figure in FIG. 4B). performing measurement by light enters from the inlet opening O ₄₀ as the incident angle becomes 40 °. At this time, the entrance opening _{O 10} installing the standard white plate 41.

(3) Others In the present disclosure, the cover tape has a light transmittance of 80% or more at an incident angle of 40 degrees, particularly 82% or more, and a light absorption rate of 10% or less at an incident angle of 40 degrees. Above all, it is particularly preferable that it is 5% or less.

V. Other Structure (1) Intermediate Layer In the present disclosure, for example, as shown in FIG. 3, an intermediate layer 5 may be arranged between the base material layer 2 and the heat seal layer 3, if necessary. The intermediate layer can improve the adhesion between the base material layer and the heat seal layer. Further, since the intermediate layer can improve the cushioning property when the cover tape of the present disclosure is heat-sealed to the carrier tape, heat can be applied to the heat-sealing layer more uniformly.

The material of the intermediate layer is appropriately selected depending on the material of the base material layer and the heat seal layer, and examples thereof include polyolefins such as polyethylene and polypropylene, polyurethane, and polyester. The thickness of the intermediate layer can be, for example, 5 μm or more and 50 μm or less.

A film can be used as the intermediate layer. In this case, the method of laminating the base material layer and the intermediate layer is not particularly limited, and a known method can be used. For example, a method of laminating a pre-made film to a base material layer with an adhesive, a method of extruding a raw material of a heat-melted film onto a base material layer with a T-die or the like, and the like to obtain a laminate. The adhesive is the same as that described in the section of the heat seal layer.

(2) Anchor layer Further, an anchor layer may be provided between the base material layer and the intermediate layer, or between the intermediate layer and the heat seal layer. By forming the anchor layer, even when the base material layer, the intermediate layer or the heat seal layer has poor adhesive strength, between the base material layer and the intermediate layer, or between the intermediate layer and the heat seal layer. Adhesion can be improved. The anchor layer may be appropriately selected depending on the material used for the base material layer, the intermediate layer, and the heat seal layer, and is not particularly limited. The anchor layer can be formed of, for example, a resin having good adhesiveness such as an olefin-based, acrylic-based, isocyanate-based, urethane-based, or ester-based adhesive.

B. Packaging Body The packaging body of the present disclosure includes a carrier tape having a plurality of storage portions for storing electronic parts, electronic parts stored in the storage parts, and the above-mentioned cover tape arranged so as to cover the storage parts. And.

In the package of the present disclosure, the carrier tape may be transparent or opaque, but an opaque carrier tape is preferable. This is because the effect of the cover tape having a high transmittance of the present disclosure is exhibited more remarkably.

Note that the present disclosure is not limited to the above embodiment. The above-described embodiment is an example, and any object having substantially the same structure as the technical idea described in the claims of the present disclosure and exhibiting the same effect and effect is the present invention. Included in the technical scope of the disclosure.

Examples and comparative examples are shown below, and the present disclosure will be described in more detail.
(Example 1)
As a base material layer, a 25 μm-thick biaxially stretched polyethylene terephthalate film (FE2002 manufactured by Futamura Chemical Co., Ltd., hereinafter referred to as PET film) having corona treatment on both sides was prepared. By applying the antistatic composition 1 to one surface side of the PET film, an antistatic layer having a thickness of less than 1 μm (about 53 nm) was formed. A urethane-based anchor coating agent (Takenate A-3075 / Takelac A-3210 (mass ratio) = 3/1 diluted with 5% ethyl acetate) was applied to the surface of the PET film opposite to the surface on which the antistatic layer was formed. It was applied to form an anchor layer.

Next, an intermediate layer having a thickness of 15 μm was formed on the surface side of the PET film on which the anchor layer was formed by a melt extrusion laminating method using a polyethylene resin (Novatec LC600A, manufactured by Japan Polyethylene Corporation). Next, on the surface side of the intermediate layer opposite to the anchor layer side, the heat seal composition 1 was used, and the thickness was 15 μm, the surface arithmetic mean roughness Ra was 0.68 μm, and the maximum height was 5. A 9 μm heat seal layer was formed to prepare a cover tape 1. The cover tape 1 is composed of an antistatic layer (53 nm) / base material layer (25 μm) / anchor layer / intermediate layer (15 μm) / heat seal layer (15 μm).

(Example 2)
Same as in Example 1 except that a heat seal layer having a thickness of 15 μm, an arithmetic mean roughness of the surface of Ra 0.46 μm, and a maximum height of 3.5 μm was formed by the melt extrusion laminating method using the heat seal composition 1. The cover tape 2 was produced by the method of.

(Example 3)
The cover tape 3 is applied in the same manner as in Example 1 except that an antistatic layer having a thickness of less than 1 μm (about 140 nm) is formed by applying the antistatic composition 2 to one surface side of the PET film. Made.

(Comparative Example 1)
The cover tape 4 was produced in the same manner as in Example 1 except that the antistatic layer was not formed on one surface side of the PET film. The cover tape 4 is composed of a base material layer (25 μm) / anchor layer / intermediate layer (15 μm) / heat seal layer (15 μm).

(Comparative Example 2)
As a base material layer, a 25 μm-thick biaxially stretched polyethylene terephthalate film (E7415 manufactured by Toyobo Co., Ltd., hereinafter referred to as PET film) having antistatic treatment on one side was prepared. Urethane-based anchor coating agent (Takenate A-3075 / Takelac A-3210 (mass ratio) = 3/1 diluted with 5% ethyl acetate) is applied to the side of the PET film opposite to the antistatic surface. It was applied to form an anchor layer.

Next, an intermediate layer having a thickness of 30 μm was formed on the surface side of the PET film on which the anchor layer was formed by a melt extrusion laminating method using a polyethylene resin (Novatec LC600A, manufactured by Japan Polyethylene Corporation). Next, by applying the heat seal composition 2 to the surface side of the intermediate layer opposite to the anchor layer side, a heat seal having a thickness of 2 μm, a surface arithmetic mean roughness Ra of 0.64 μm, and a maximum height of 3.5 μm is applied. A layer was formed to prepare a cover tape 5. The cover tape 5 is composed of an antistatic layer (less than 1 μm) / base material layer (25 μm) / anchor layer / intermediate layer (30 μm) / heat seal layer (2 μm).

(Comparative Example 3)
A cover tape 6 was produced in the same manner as in Example 1 except that an antistatic layer having a thickness of 1 μm was formed by applying the antistatic composition 1 to one surface side of the PET film.
The cover tape 6 is composed of an antistatic layer (1 μm) / base material layer (25 μm) / anchor layer / intermediate layer (15 μm) / heat seal layer (15 μm).

(Antistatic Composition 1)
The following main agent and curing agent are mixed at a dry solid content ratio of 10: 3, and ethylene glycol is added as a conductive auxiliary agent by the same weight as the dry solid content of the mixture. Then, the antistatic composition 1 having a total solid content concentration of 1.2% by mass was prepared with a diluting solvent 2-propanol and distilled water.
-Main agent: Acrylic polymer compound having carboxylate anion in the side chain, and polythiophene conductive polymer compound PEDOT / PSS (Product name Aracoat AS-601D manufactured by Arakawa Chemical Co., Ltd.)
-Curing agent: Polyfunctional aziridine-based curing agent (product name: Aracoat CL-910, manufactured by Arakawa Chemical Co., Ltd.)

(Antistatic composition 2)
The following main agent and curing agent were mixed at a dry solid content ratio of 10: 1, and an antistatic composition 2 having a total solid content concentration of 3.0% by mass was prepared with a diluting solvent of methanol.
-Main agent: Acrylic polymer compound having a quaternary ammonium salt group, a carboxyl group, and a (meth) acrylic acid ester group in the side chain (Acryt 1SX-1123 (manufactured by Taisei Fine Chemicals Co., Ltd.))
-Curing agent: Polyfunctional aziridine-based curing agent Tris (1-aziridine propionic acid) 1,1,1-propanetriyltrismethylene (Product name: Chemitite PZ-33 (manufactured by Nippon Shokubai Co., Ltd.))

(Heat Seal Composition 1)
-Ethylene-vinyl acetate copolymer (Evaflex EV550, manufactured by Mitsui Dow Polychemical Co., Ltd.) 65 parts by mass-Low density polyethylene resin (Sumikasen L705, manufactured by Sumitomo Chemical Co., Ltd.) 20 parts by mass-Hydrogenated petroleum resin (Arcon P-125) , Arakawa Chemical Co., Ltd.) 11 parts by mass
-Mixture with 4 parts by mass of non-ionic surfactant (Rikemaster ELB-347, manufactured by Riken Vitamin Co., Ltd.).

(Heat seal composition 2)
A composition obtained by mixing an acrylic adhesive resin (A450A, manufactured by DIC Graphics) and a transparent conductive powder tin oxide (T-1, manufactured by Mitsubishi Materials) at a dry solid content ratio of 1: 3.

(Measurement of surface resistivity)
Surface resistivity of the surface of the cover tapes 1 to 6 manufactured above on the side where the antistatic layer is arranged (the surface opposite to the side on which the heat seal layer is arranged) (surface resistivity of the antistatic layer). ) And the surface resistivity of the surface on the side where the heat seal layer is arranged were measured by the method described in "A. Cover tape for packaging electronic parts I. Antistatic layer" above. The sample size was 50 cm × 40 cm.
The results are shown in Table 1.

(Measurement of transmittance and absorption rate)
The light transmittance and absorptance of the cover tapes 1 to 6 manufactured above at an incident angle of 0 ° and an incident angle of 40 ° are described in "A. Cover tape for packaging electronic parts IV. Cover tape (1) Transmittance". , "A. Cover tape for packaging electronic parts IV. Cover tape (2) Absorption rate". The results are shown in Table 1.

(Preparation of package sample)
A package sample was prepared under the following taping conditions. While continuously arranging 100 electronic components (0603 size_capacitor) in the cavity of the paper carrier tape, heat seal the paper carrier tape and cover tape using the taping machine NST-35 (Nitto Kogyo) under the following conditions. A roll-shaped package sample was obtained by winding while rolling.

(Taping conditions)
-Paper carrier tape: Hokuetsu Corporation 0.31 mm thick 8 mm width Virgin paper-Paper carrier tape Feed hole pitch: 2 mm
・ Taping temperature 180 ℃
・ Taping speed 3500 tact ・ Taping trowel size 0.6mm x 2 wires ・ Taping trowel length (seal length at 1 tact) 8 ± 1mm

(Visibility evaluation)
The visibility of the electronic components through the cover tape of the prepared package sample was evaluated by the following evaluation method.
Evaluation method: The filled electronic component is observed with an optical microscope through the cover tape from an angle of 0 ° and 40 ° with respect to the vertical direction of the cover tape surface (lens HOZAN L-816), and the electronic component is evaluated. Was judged to be recognizable. A total of 100 chips were inspected and the pass rate was calculated.

From Table 1, the cover tape of the present disclosure has excellent antistatic performance, and not only the light transmittance at an incident angle of 0 degrees but also the light transmittance at an incident angle of 40 degrees is 80% or more. there were. Therefore, it has been shown that deterioration of visibility can be suppressed when observing or performing camera inspection from an oblique direction at an angle rather than perpendicular to the surface of the cover tape.

On the other hand, the cover tape 2 of Comparative Example 1 was inferior in antistatic performance, and the cover tape 3 of Comparative Example 2 was inferior in light transmittance at an incident angle of 40 degrees. In Comparative Example 2, since a large amount of conductive fine particles were blended in the heat seal layer, reflection and scattering of the fine particles and light in the heat seal layer were promoted, and as a result, the absorption rate was increased. Further, in Comparative Example 3, since the antistatic layer was thick, the transmittance was lowered, and the visibility was good at an incident angle of 0 degrees, but the visibility was deteriorated at an incident angle of 40 degrees.

1 ... Cover tape 2 ... Base material layer 3 ... Heat seal layer 4 ... Antistatic layer 5 ... Intermediate layer 10 ... Package 11 ... Carrier tape 12 ... Storage 13 ... Electronic components

Claims

Base layer and
A heat seal layer arranged on one surface side of the base material layer and
An antistatic layer arranged on the surface side of the base material layer opposite to the surface on the heat seal layer side,
It is a cover tape for packaging electronic parts with
The surface resistivity of the surface on the side where the antistatic layer is arranged is 1 × 10 10 Ω / □ or less.
The heat seal layer contains an antistatic agent and contains
The cover tape for packaging electronic components is a cover tape for packaging electronic components, which has a light transmittance of 80% or more at an incident angle of 40 degrees.
Base layer and
A heat seal layer arranged on one surface side of the base material layer and
An antistatic layer arranged on the surface side of the base material layer opposite to the surface on the heat seal layer side,
It is a cover tape for packaging electronic parts with
The surface resistivity of the surface on the side where the antistatic layer is arranged is 1 × 10 10 Ω / □ or less.
The heat seal layer contains an antistatic agent and contains
The cover tape for packaging electronic components is a cover tape for packaging electronic components, which has a light absorption rate of 10% or less at an incident angle of 40 degrees.
The cover tape for packaging electronic components according to claim 1 or 2, wherein the surface resistivity of the surface on the side on which the heat seal layer is arranged is 1 × 10 14 Ω / □ or less.
The cover tape for packaging electronic components according to any one of claims 1 to 3, wherein the thickness of the antistatic layer is thinner than the thickness of the heat seal layer.
A carrier tape with multiple storage units for storing electronic components,
Electronic components stored in the storage unit and
The cover tape for packaging electronic components according to any one of claims 1 to 4, which is arranged so as to cover the storage portion.
A packaging body.