JP2002114267A - Bottom cover tape for transporting electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bottom cover tape for transporting electronic parts in which it has a superior adhering characteristic against a carrier tape and either adhesion or melting of the tip-type electronic parts can be restricted. SOLUTION: This bottom cover tape for transporting an electronic parts in a bottom cover tape adhered by a carrier tape and heat to cover a bottom surface of a hole for storing electronic parts formed in the carrier tape in an electronic parts transporting member, wherein a substrate layer of the bottom tape is constituted of a plastic film. This tape is comprised of at least a substrate layer, a static electricity neutralization adhesive agent layer and a thermo- adhering layer. A frictional charged voltage at each of the surfaces of the substrate layer and the thermo-adhering layer is 3,000 V or less. A total light beam transmittance is 80% or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bottom cover tape for transporting electronic components, which is used for transporting electronic components until they are mounted on a substrate.

[0002]

2. Description of the Related Art Chip-type electronic components (chip components) such as chip resistors and chip-type multilayer ceramic capacitors.
As a transport form of electronic components such as, the bottom surface of a paper carrier (carrier tape) having electronic component storage holes formed at regular intervals in the length direction of the tape-shaped cardboard is coated with a bottom cover tape having a thermal adhesive layer. A storage pocket is prepared by heat sealing (taping), and then the electronic component is inserted into the storage pocket, and the upper surface of the paper carrier is heat-sealed with a top cover tape to encapsulate the electronic component. Taping reel systems, which are wound and conveyed in a shape, are widely used. And in the manufacturing process of the circuit board and the like of the transfer destination, after the top cover tape is peeled off, the inserted electronic component is pushed up with a pin from the lower surface or the outer surface of the bottom cover tape, and then suctioned with an air nozzle, or An automatic incorporation system that supplies an inserted electronic component onto a substrate by a method of directly sucking the inserted electronic component with an air nozzle after peeling the cover tape has become mainstream.

In such a taping reel system, a paper base material such as Japanese paper is used as a base material of a base layer used for a bottom cover tape. Bundling fibers may be mixed.
As described above, when the binding fibers are mixed, heat is not sufficiently transmitted to the heat bonding layer (bonding layer) when performing heat bonding using a hot iron or the like from the base material layer side, resulting in poor heat conduction. Therefore, the heat bonding layer is not sufficiently softened, and the bottom cover tape does not sufficiently adhere to the carrier tape, which causes a problem that poor adhesion is caused. The adhesiveness of the bottom cover tape to the carrier tape can be improved by lowering the softening temperature of the adhesive layer or forming the adhesive layer using a material having high adhesiveness. However, in such a method of improving adhesiveness using an adhesive layer, an electronic component may adhere or fuse to the adhesive layer during transportation or storage. Therefore, in a process of manufacturing a circuit board or the like, a phenomenon occurs in which an electronic component cannot be picked up by an air nozzle, which causes a problem that a suction rate of the electronic component by the air nozzle decreases. In addition, it is only necessary to stabilize the original quality of the paper of the base material layer and to eliminate the binding fibers, but it is difficult to completely eliminate the binding fibers in the paper production method.

Further, since the base material layer is made of paper, the light transmittance of a sensor for confirming whether the electronic component is sealed in the storage hole is low, and the optical sensor recognizes the sealed state of the electronic component. Is also a problem.

[0005] Despite these problems, the reason why paper is used for the base material layer is that the base material layer is easily broken when the pins are pushed up. However, in recent years, a system using a method of adsorbing with an air nozzle has become mainstream, and thus the necessity of the base material of the base material layer being necessarily paper has been eliminated.

In particular, in recent years, electronic components have become increasingly lighter, thinner and smaller, and the electronic components are reliably accommodated in holes for accommodating the electronic components, and the electronic components are reliably picked up by an air nozzle in a manufacturing process of a circuit board or the like. There is a need for reliability.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a bottom cover tape for transporting electronic components, which has excellent adhesiveness to a carrier tape and can suppress adhesion or fusion of electronic components. Another object of the present invention is to provide a bottom cover tape for transporting electronic components, which is excellent in antistatic properties. Still another object of the present invention is to provide a bottom cover tape for transporting electronic components, which is excellent in transparency.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object. As a result, when the base layer of the bottom cover tape is formed of a specific base material, the adhesiveness to the carrier tape is excellent, and Finding that adhesion or fusion to the adhesive layer surface of chip-type electronic components can be significantly suppressed,
The present invention has been completed.

That is, the present invention relates to a bottom cover tape which is adhered by heat to a carrier tape so as to cover a bottom surface of an electronic component storage hole formed in the carrier tape of the electronic component carrier. A bottom cover tape for transporting electronic components, wherein the base layer is made of a plastic film.

In the present invention, the bottom cover tape preferably comprises at least a base material layer, an electrostatic neutralizing adhesive layer and a thermal adhesive layer.

[0011] In a preferred embodiment of the bottom cover tape for transporting electronic parts of the present invention, the surface voltage of each of the base layer side and the heat bonding layer side is 3000 V or less. Further, the total light transmittance is preferably 80% or more.

[0012]

Embodiments of the present invention will be described below with reference to the drawings as necessary. FIG. 1 is a schematic sectional view showing an example of the bottom cover tape of the present invention. In FIG. 1, 1 is a bottom cover tape, 2 is a base material layer (supporting base material layer), and 3 is a heat bonding layer (adhesive layer).

The bottom cover tape 1 comprises a base layer 2 and an adhesive layer 3 provided on the base layer 2.
The base material (support base material) constituting the base material layer 2 is a plastic film having self-supporting properties. As a material of such a plastic film, a thermoplastic resin can be suitably used. More specifically, as a material of the plastic film, for example, polyester (polyester resin) such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, olefin resin such as polyethylene and polypropylene, polyvinyl chloride, cellophane, etc. Examples include cellulose-based resins and amide-based resins such as nylon (polyamide). As a plastic film material,
Polyester resins are preferred. The material of the plastic film (such as a thermoplastic resin) can be used alone or in combination of two or more.

In the present invention, a thermoplastic resin can be used in the form of a film. The thermoplastic resin film may be a stretched film or an unstretched (uniaxially stretched or biaxially stretched) film.

The substrate layer may be a single layer or a multilayer as long as it is formed of a plastic film.

The thickness of the base material layer 2 can be appropriately selected within a range that does not impair the mechanical strength, handleability, etc., and is, for example, generally about 2 to 250 μm, and preferably about 2 to 250 μm.
It is about 0 to 200 μm.

The plastic film of the substrate layer is
Those having high transparency are preferred.

The surface of the base material layer 2 may be subjected to a conventional surface treatment, for example, a corona discharge treatment, if necessary.

The base material layer 2 may be subjected to an antistatic treatment as required. Such an antistatic treatment can be performed by a conventional method, for example, by kneading the antistatic agent into the base material layer, or by applying the antistatic agent to the surface of the base material layer.

If necessary, conventional additives such as antioxidants, ultraviolet absorbers, softeners, rust inhibitors, inorganic particles, antistatic agents (for example, quaternary ammonium Salt), a conductive metal powder, an organic conductive polymer, a coupling agent such as a titanium-based or silane-based coupling agent, and the like.

As the base polymer constituting the adhesive layer 3, for example, a thermoplastic resin such as a polyolefin resin, a polyester resin or a styrene resin, or an elastomer such as a thermoplastic elastomer can be used. These base polymers can be used alone or in combination of two or more.

As the base polymer of the heat bonding layer 3, a polyolefin resin is preferable. Examples of the polyolefin resin include polyethylene (low density polyethylene, linear low density polyethylene, metallocene catalyzed polyethylene, medium density polyethylene, high density polyethylene, etc.), polypropylene, α-olefin copolymer (ethylene-propylene copolymer) , Ethylene-butene-1 copolymer, propylene-butene-1 copolymer, etc.); ethylene-based copolymers [eg, ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer] (EMAA) and other ethylene-unsaturated carboxylic acid copolymers; ionomers; ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl methacrylate copolymer and other ethylene- (Meth) acrylate copolymer;
Ethylene-vinyl acetate copolymer (EVA); ethylene-
Vinyl alcohol copolymer, etc.].

The thickness of the heat bonding layer 3 can be appropriately selected within a range not impairing the adhesive property and the handling property, but is generally about 2 to 90 μm. The thickness of the thermal bonding layer 3 is 2μ
If less than m, the adhesive strength is weak, and if more than 90 μm, the total thickness of the tape increases, and taping failure due to sticking out of the adhesive at the time of taping tends to occur.

The heat bonding layer 3 can be formed by a conventional laminating method such as an extrusion laminating method, a co-extrusion method using a T-die tandem extruding laminator, or a dry laminating method.

The heat bonding layer 3 further includes an antioxidant such as a phosphorus-based or phenol-based agent, an ultraviolet absorber, a rust inhibitor, a softener, a surfactant, an antistatic agent, a filler, a coupling agent, and a crosslinking agent. An additive such as an agent may be blended.

FIG. 2 is a schematic sectional view showing another example of the bottom cover tape of the present invention. In FIG. 2, 11 is a bottom cover tape, 2 is a base material layer (supporting base material layer), 3 is a thermal adhesive layer (adhesive layer), and 4 is an undercoat layer.

The bottom cover tape 11 shown in FIG.
A base layer 2 and an undercoat layer 4 provided on the base layer 2
And a thermal bonding layer 3 provided on the undercoat layer 4. That is, the base material layer, the undercoat layer, and the heat bonding layer are laminated in this order. Thus, in the present invention, the undercoat layer 4 may be provided on the base material layer 2. Also, an intermediate layer can be provided between the base material layer and the heat bonding layer. The undercoat layer 4 is a layer for ensuring the interlayer strength between the base material layer 2 and the heat bonding layer 3 (when the intermediate layer is provided, the base material layer 2 and the intermediate layer). Agent. When the undercoat layer 4 is provided, it is preferable that a surface of the base material layer 2 that comes into contact with the undercoat layer 4 be subjected to a surface treatment such as a corona discharge treatment.

The adhesive for the undercoat layer 4 is preferably a urethane-based adhesive or an electrostatic neutralizing adhesive. For example, when a urethane-based adhesive is used, the interlayer strength between the base material layer 2 and the heat bonding layer 3 can be greatly increased.

When an electrostatic neutralizing adhesive is used as the adhesive for the undercoat layer 4, the antistatic property of the bottom cover tape 11 can be significantly improved. Thus, in the present invention, when an electrostatic neutralizing adhesive is used as the adhesive for the undercoat layer 4, the undercoat layer may be referred to as an "electrostatic neutralizing adhesive layer".

The electrostatic neutralizing adhesive is used to improve the adhesive strength between the laminated materials by interposing between the layers of the laminated constituent material of the insulator, and to contact both surfaces of the laminated material by friction or contact on the surface of the laminated material. It refers to those that suppress the generated static electricity. As such an electrostatic neutralizing adhesive, a cationic adhesive can be suitably used. The cationic adhesive is an adhesive having a cationic group, and for example, a resin having a quaternary ammonium group is preferable.
More specifically, as the static neutralizing adhesive, for example,
A quaternary ammonium salt type acrylic copolymer resin may be used. The electrostatic neutralizing adhesive can be used alone or in combination of two or more.

As the electrostatic neutralizing adhesive, for example, "Bondip PA-100" manufactured by Altec Corporation can be used.

As described above, the bottom cover tape of the present invention is optimally composed of at least the base material layer, the electrostatic neutralizing adhesive layer and the thermal adhesive layer.

The undercoat layer (static neutralizing adhesive layer) made of the static neutralizing adhesive can be formed between the intermediate layer and the heat bonding layer 3. For example, an undercoat layer made of a urethane-based adhesive or the like is provided between the base layer 2 and the intermediate layer, and an undercoat layer made of an electrostatic neutralizing adhesive is provided between the intermediate layer and the heat bonding layer 3. Good.

The thickness of the undercoat layer 4 is preferably about 0.05 to 30 μm. When the undercoat layer 4 is formed of a urethane-based adhesive or the like, it is preferably 0.05 to 10 μm.
m.

When the undercoat layer 4 is made of an electrostatic neutralizing adhesive, the thickness of the undercoat layer, that is, the thickness of the electrostatic neutralizing adhesive layer is not particularly limited, but may be 0.1 to 0.1.
Preferably it is 5 μm. If the thickness of the electrostatic neutralizing adhesive layer is less than 0.1 μm, the frictional voltage on the surface of the bottom cover tape is increased, and may exceed 3000 V. On the other hand, when the thickness of the static neutralizing adhesive layer exceeds 5 μm, the static neutralizing effect of suppressing generation of static does not change so much, and there is little merit in cost. The undercoat layer 4 can be formed by a conventional coating method or the like.

In the case where the base material layer 2 and the heat bonding layer 3 can be laminated with high bonding strength, the undercoat layer 4 is not necessarily provided.

In the present invention, the antistatic property of the bottom cover tape can be remarkably improved by providing an electrostatic neutralizing adhesive layer between the base material layer and the heat adhesive layer. The friction band voltage of the surface of the bottom cover tape on the base material layer side and / or the heat bonding layer side is preferably 3000 V or less, particularly preferably 1000 V or less. The magnitude of the triboelectric voltage of the bottom cover tape can be adjusted by the type of the static neutralizing adhesive in the static neutralizing adhesive layer, the thickness of the layer, and the like.
Thus, with the bottom cover tape of the present invention, it is possible to suppress the generation of static electricity, and it is possible to suppress or prevent the adverse effects of static electricity on the electronic components sealed in the carrier material.

The bottom cover tape of the present invention preferably has high transparency. Specifically, the total light transmittance of the bottom cover tape is 80% or more (preferably 9%).
0% or more). If the total light transmittance of the bottom cover tape is less than 80%, the light transmission of a sensor for confirming whether or not the electronic component is sealed in the storage hole in the electronic component carrier (electronic component carrier material). In some cases, it may be difficult to recognize the sealed state of the electronic component by the optical sensor.

The total light transmittance of the bottom cover tape can be adjusted by appropriately selecting the materials constituting each layer such as the base layer, the undercoat layer, the intermediate layer, and the heat bonding layer and the thickness of each layer. In the present invention, the substrate layer is not made of paper,
Since a plastic film is used, the total light transmittance of the bottom cover tape can be 80% or more.

In the present invention, each layer such as the base material layer and the heat bonding layer may be subjected to an antistatic treatment. When the bottom cover tape is not provided with the static neutralizing adhesive layer, it is preferable that the base layer and / or the heat bonding layer (particularly, the base layer) have been subjected to an antistatic treatment. As an antistatic treatment method for the substrate layer in which the substrate is a plastic film, a conventional antistatic treatment method can be employed. In such a conventional antistatic treatment,
Antistatic agents can be used. In addition, as an antistatic agent, a cationic antistatic agent is suitable. Examples of the cationic antistatic agent include a quaternary ammonium salt type antistatic agent, a quaternary ammonium resin type antistatic agent,
And imidazoline-type antistatic agents. The antistatic agent can be used alone or in combination of two or more.

The bottom cover tape of the present invention can be manufactured by laminating each layer. For example, when a T-die extrusion laminator is used, an adhesive for an undercoat layer is applied to a substrate, and after drying, an adhesive layer is formed on the undercoat layer using a T-die extrusion laminator. Thereby, a bottom cover tape can be manufactured. The undercoat layer and the electrostatic neutralizing adhesive layer can be appropriately formed using equipment having conventional coating equipment.

The heat bonding layer 3 may be formed directly on the base material layer 2 as shown in FIG.
An undercoat layer or another layer other than the undercoat layer (eg, an intermediate layer)
May be formed. That is, the bottom cover tape of the present invention may include an undercoat layer, an intermediate layer, and the like, if necessary. When the undercoat layer and the intermediate layer are formed, the undercoat layer can be formed between the base layer and the intermediate layer, and the intermediate layer can be formed between the undercoat layer and the heat bonding layer. . The intermediate layer can be made of, for example, a polyolefin-based resin.

The bottom cover tape of the present invention is used as a bottom cover tape in an electronic component carrier (a carrier material for electronic components). The electronic component carrier can be constituted by a carrier tape, a bottom cover tape, and a top cover tape. As a typical example of such an electronic component carrier, a carrier tape in which electronic component housing holes for housing electronic components are formed at predetermined intervals in a length direction at a substantially central portion in a width direction, and A carrier comprising an electronic component conveying bottom cover tape for covering the lower surface or the bottom surface of the electronic component housing hole, and an electronic component conveying cover tape for covering the upper surface of the electronic component housing hole. Is mentioned.

As the material of the carrier tape, any material having self-supporting properties may be used. For example, paper such as Japanese paper, crepe paper, synthetic paper, mixed paper, composite paper; polyethylene, polypropylene, polyethylene terephthalate, polychlorinated paper Plastic films or sheets such as vinyl and cellophane; metal foils and the like can be used.

As the top cover tape for transporting electronic components, a conventional top cover tape can be used. For example, a support made of paper, a plastic film or a sheet, and a base polymer such as a polyolefin resin are used. And a top cover tape formed at least with an adhesive layer.

FIG. 3 is a schematic cross-sectional view in the length direction showing the use state of the electronic component carrier using the bottom cover tape shown in FIG. In FIG. 3, 1 is a bottom cover tape, 5 is an electronic component carrier, 6 is a carrier tape, 7 is a top cover tape, 8 is an electronic component storage hole, and 9 is an electronic component. Note that a chip-type electronic component is preferably used as the electronic component.

The electronic component carrier 5 is provided with an electronic component storage hole 8.
Carrier tape 6 formed at regular intervals in the length direction
And a bottom cover tape 1 provided on the lower surface of the carrier tape 6 and a top cover tape 7 provided on the upper surface of the carrier tape 6. In the electronic component carrier 5, the electronic component 9 is inserted into a storage pocket formed by heat-sealing the lower surface of the carrier tape 6 with the bottom car tape 1, and the upper surface of the carrier tape 6 is thermally sealed with the top cover tape 7. After sealing, it is wound and transported in a reel shape.

The surface of the bottom cover tape 1 that contacts the lower surface of the carrier tape 6 is the surface of the bottom cover tape 1 on the side of the heat bonding layer 3. That is, heat sealing can be performed using the heat bonding layer 3 of the bottom cover tape 1.

As described above, the bottom cover tape is bonded to the carrier tape by heat so as to cover the bottom surface of the electronic component storage hole formed in the carrier tape in the electronic component carrier.

At this time, the base layer 2 of the bottom cover tape 1
Is made of a plastic film, the bottom cover tape 1 and the carrier tape 6 are firmly adhered to each other,
During the transportation, the bottom cover tape 1 does not peel off and the electronic component 9 does not fall. In addition, since the adhesiveness of the thermal adhesive layer 3 itself of the bottom cover tape 1 is not increased,
The adhesion or fusion of the electronic component 9 to the thermal bonding layer 3 of the bottom cover tape 1 is not promoted, and the electronic component 9 adheres or fuses to the surface of the thermal bonding layer 3 of the bottom cover tape 1. Can be suppressed.

Therefore, in the process of manufacturing a circuit board or the like, the chip component suction rate of the air nozzle in the automatic assembling system is remarkably improved, and the electronic component (chip type electronic component or the like) can be reliably supplied onto the substrate.

Further, even if the base material layer is made of a plastic film, the antistatic property of the bottom cover tape can be easily improved by providing an electrostatic neutralizing adhesive layer between the base material layer and the heat bonding layer. Can be improved. Therefore, even if a plastic film is used as the base layer, a bottom cover tape having excellent antistatic properties can be easily produced.

Further, since the base material layer is formed of a plastic film, high transparency can be maintained, and a bottom cover tape having excellent transparency can be easily obtained. Therefore, light from a sensor for confirming whether or not the electronic component is sealed in the storage hole easily passes through the bottom cover tape. Therefore, the optical sensor has high transparency in the bottom cover tape, and it is easy to recognize the sealed state of the electronic component by the optical sensor.

Accordingly, the reliability from the transfer of the electronic component to the process of assembling the electronic component into the circuit board can be remarkably improved.

The bottom cover tape for transporting electronic components according to the present invention is an electronic component transport body suitably used for transporting a wide range of chip-type electronic components such as resistors such as chip fixed resistors and capacitors such as multilayer ceramic capacitors. Useful as a bottom cover tape. In this case, it can be suitably used as a bottom cover tape for a paper or plastic carrier tape.

[0056]

The bottom cover tape for transporting electronic components of the present invention is excellent in adhesiveness to a carrier tape and can significantly suppress the adhesion or fusion of electronic components. Further, the antistatic property can be easily improved. Moreover,
High transparency can be maintained.

[0057]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 A polyethylene terephthalate film (trade name "E-5")
100, # 16 ", manufactured by Toyobo Co., Ltd., on one side of the corona discharge treated surface, on the side of the corona discharge treated surface, an electrostatic neutralizing adhesive (trade name" Bondip PA-100 ", manufactured by Altec). A bottom cover tape was produced by laminating a thermal adhesive layer made of low-density polyethylene (trade name “L-1885”, manufactured by Asahi Kasei Kogyo Co., Ltd.) with an extruder laminator via the agent layer. In addition, the thickness of the obtained bottom cover tape was 42 μm.

Example 2 Antistatic treated polyethylene terephthalate film (trade name “E-7415, # 16”, manufactured by Toyobo Co., Ltd.)
A urethane-based adhesive (trade name “AD335A / C”) is provided on the corona discharge treated surface side of the antistatic treatment and one-sided corona discharge treatment.
AT10L ", a low-density polyethylene (trade name" L-1885 ",
A thermal adhesive layer made of Asahi Kasei Kogyo Co., Ltd.) was laminated by an extrusion laminator to produce a bottom cover tape. The thickness of the obtained bottom cover tape is 42 μm.
Met.

Example 3 Polyethylene terephthalate film (trade name “E-5”)
100, # 16 ", a single-sided corona discharge treatment (manufactured by Toyobo Co., Ltd.) on the corona discharge treatment surface side via an undercoat layer made of a urethane-based adhesive (trade name" AD335A / CAT10L ", manufactured by Toyo Morton Co., Ltd.) A thermal adhesive layer made of low-density polyethylene (trade name “L-1885”, manufactured by Asahi Chemical Industry Co., Ltd.) was laminated by an extrusion laminator to produce a bottom cover tape. The thickness of the obtained bottom cover tape was 41 μm.

Comparative Example 1 A thermal adhesive layer made of low-density polyethylene (trade name "L-1885", manufactured by Asahi Kasei Kogyo Co., Ltd.) was laminated on Japanese paper (thickness: 40 μm, basis weight: 18 g / m ² ) by an extrusion laminator. Thus, a bottom cover tape was produced. The thickness of the obtained bottom cover tape was 55 μm.

Evaluation Tests For the bottom cover tapes obtained in Examples and Comparative Examples, evaluations of tensile strength, elongation, adhesive strength, surface resistance, frictional voltage, total light transmittance and adhesion failure rate were as follows. I went. The evaluation results are shown in Table 1.

[Table 1]

(Tensile strength and elongation) The tensile strength and elongation were measured at a tensile speed of 300 mm / min.

(Adhesive force) Paper carrier (Hokuetsu Paper Mills, Ltd.)
HOCTO-60) at 170 ° C. with an iron pressing force of 1.5 using a heat sealing machine (taping machine manufactured by Tokyo Wells Co., Ltd.) on the surface of HOCTO-60.
kgf (14.7 N), heat-sealed under the conditions of 1200 PCS / min.
The adhesive strength was measured under the conditions of 0 mm / min and a peel angle of about 180 °.

(Surface Resistance Value) The surface resistance value (Ω / □) of both the base layer side and the heat bonding layer side of each bottom cover tape was measured using a high resistivity meter Hiresta UP (manufactured by Mitsubishi Chemical Corporation). ) In an atmosphere of 23 ° C./60% RH under an applied voltage of 500 V × 1 minute.

(Friction Band Voltage) According to JIS L 1094, the surface of the bottom cover tape on the side of the heat bonding layer was rubbed with a cloth, and the friction band voltage of the heat bonding layer side was measured.

(Total light transmittance) For each bottom cover tape, the total light transmittance (%) was measured using a haze meter.
Was measured.

(Adhesion failure rate) Length 1000 per roll
When 100 rolls of the bottom cover tape of m are heat-sealed (heat-bonded) to a paper carrier tape, if even one of the rolls has a defective bonding position, it is determined to be defective and the ratio (%) is calculated. The ratio was defined as an adhesion failure rate (%).

As shown in Table 1, the bottom cover tapes according to Examples 1 to 3 are superior to the bottom cover tape according to Comparative Example 1 in tensile strength, elongation, adhesive strength, adhesive failure rate and the like. This is because a plastic film is used as the base material layer.

Further, the bottom cover tape according to Example 1 having an electrostatic neutralizing adhesive layer and the bottom cover tape according to Example 2 using a plastic film subjected to antistatic treatment also have a low frictional voltage.

In particular, since the plastic film is used, the total light transmittance is excellent, and the electronic components in the electronic component carrier can be easily recognized.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a bottom cover tape for transporting electronic components of the present invention.

FIG. 2 is a schematic sectional view showing another example of the bottom cover tape for transporting electronic components of the present invention.

FIG. 3 is a schematic cross-sectional view in the length direction showing a use state of an electronic component carrier using the bottom cover tape of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bottom cover tape 2 Base layer 3 Thermal bonding layer 4 Undercoat layer 5 Electronic component carrier 6 Carrier tape 7 Top cover tape 8 Electronic component storage hole 9 Chip type electronic component 11 Bottom cover tape

Continued on the front page F term (reference) 3E067 AA11 AB47 AC04 BA26A BB14A BB15A BB25A CA11 CA21 CA24 EA06 EC25 FC01 GD07 GD08 3E096 AA06 BA09 CA15 DA14 DA17 DC01 EA02X EA02Y FA07 FA14 GA04 4J004 AA05 AAA AA AA AA AA A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A FA05 FA08

Claims (4)

[Claims] 1. A bottom cover tape adhered by heat to a carrier tape so as to cover a bottom surface of an electronic component storage hole formed in a carrier tape of an electronic component carrier, wherein a base layer of the bottom tape is provided. Is a bottom cover tape for transporting electronic components made of plastic film. 2. The bottom cover tape for transporting electronic parts according to claim 1, comprising at least a base layer, an electrostatic neutralizing adhesive layer and a thermal adhesive layer. 3. The bottom cover tape for transporting electronic components according to claim 1, wherein the friction band voltage on each surface of the base material layer side and the heat bonding layer side is 3000 V or less. 4. The bottom cover tape for conveying electronic parts according to claim 1, wherein the total light transmittance is 80% or more.