CN110770144B

CN110770144B - Cover tape and electronic component package

Info

Publication number: CN110770144B
Application number: CN201880041627.8A
Authority: CN
Inventors: 平松正幸; 阿部皓基
Original assignee: Sumitomo Bakelite Co Ltd
Current assignee: Sumitomo Bakelite Co Ltd
Priority date: 2017-06-22
Filing date: 2018-06-07
Publication date: 2021-10-26
Anticipated expiration: 2038-06-07
Also published as: JPWO2018235606A1; TW201906774A; WO2018235606A1; JP6566149B2; TWI753177B; CN110770144A

Abstract

A cover tape (10) for packaging electronic components, comprising: the adhesive sheet comprises a base material layer (3) and an intermediate layer (1) laminated on one surface of the base material layer (3), wherein when the dimension of the intermediate layer (1) at 23 ℃ is T0 and the dimension after heating at 80 ℃ for 2 hours is T1, the intermediate layer represented by the following formula (1) has a dimensional change rate of-4% or more and 4% or less in the MD direction, which is the flow direction, 0% or more and 2% or less in the TD direction, and the dimensional change rate (%) [ (T0-T1)/T0] × 100 formula (1).

Description

Cover tape and electronic component package

Technical Field

The present invention relates to a cover tape (cover tape) and an electronic component package. More particularly, the present invention relates to a cover tape that can heat-seal a carrier tape (c carrier tape) having storage pockets for transporting electronic components such as semiconductor IC chips, and an electronic component package obtained by heat-sealing the cover tape to the carrier tape in which the electronic components are stored.

Background

After manufacturing, electronic components such as semiconductor IC chips are packaged with a packaging material for preventing contamination during the period from the time of supply to the mounting process, and are stored and transported in a state of being wound around a paper or plastic reel. In the packaging of electronic components, a tape-shaped packaging material is used in accordance with a mounting process of mounting the electronic components on a substrate by an automatic mounting apparatus, and the packaging material is composed of a carrier tape in which a plurality of concave storage pockets are formed on a long sheet at predetermined intervals, and a cover tape heat-sealed to the carrier tape. The electronic component packaged with such a packaging material is automatically taken out from the package and mounted on the electronic circuit board after the cover tape is peeled off from the carrier tape.

As a cover tape used as a packaging material for electronic component packages, for example, patent document 1 discloses a cover tape including a base material layer, an intermediate layer, and a sealant layer, in which the intermediate layer has a specific heat shrinkage rate, so that the cover tape does not float during heat sealing, and the occurrence of a gap between the cover tape and a carrier tape can be suppressed. For example, patent document 2 discloses a cover tape including a base layer and a sealant layer, in which a difference between heat shrinkage rates of the base layer and the sealant layer is set to a specific value, whereby warpage of the cover tape during heat sealing can be suppressed, and positional displacement occurring when the cover tape is heat sealed to a carrier tape can be reduced.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-20750

Patent document 2: japanese patent laid-open No. 2010-76832.

However, the cover tapes described in

patent documents

1 and 2 also do not sufficiently control the floating generated at the time of heat sealing.

Disclosure of Invention

Technical problem to be solved by the invention

The present invention has been made in view of the above circumstances, and provides a cover tape that can reduce the occurrence of arc-shaped lifting of the cover tape due to heat shrinkage of the cover tape during heat sealing, and can reduce the occurrence of a gap between the cover tape and a carrier tape. Thus, a cover tape capable of suppressing the protrusion of electronic components from a carrier tape and the rotation or falling of the electronic components, thereby improving the mounting efficiency of the electronic components is provided.

Means for solving the technical problem

As a result of intensive studies, the inventors of the present invention have found that when a heat sealing iron is used to heat seal a cover tape to a carrier tape, the heat sealing iron is brought close to the cover tape and the cover tape is heated, whereby the heat sealing front cover tape is heat-shrunk and expanded into an arc shape. When the cover tape having been expanded is heat-sealed to the carrier tape with a heat-sealing iron, the cover tape is heat-sealed to the carrier tape while being floated in an arc shape, and therefore a gap is formed between the cover tape and the carrier tape. The inventors of the present invention found that: the present inventors have completed the present invention by obtaining a cover tape having reduced floating at the time of heat sealing by controlling the dimensional change of an intermediate layer at 80 ℃ which is the temperature at which a heat sealing iron approaches the cover tape, on a cover tape having a base material layer and the intermediate layer.

According to the present invention, there is provided a cover tape for electronic component packaging, comprising a base material layer and an intermediate layer laminated on one surface of the base material layer,

when the dimension of the intermediate layer at 23 ℃ is T0 and the dimension after heating at 80 ℃ for 2 hours is T1, the dimension change rate in the flow direction (MD direction) of the intermediate layer represented by the following formula (1) is-4% or more and 4% or less, and the dimension change rate in the width direction (TD direction) is 0% or more and 2% or less,

the dimensional change rate (%) [ (T0-T1)/T0] × 100 formula (1).

Further, according to the present invention, there is provided an electronic component package including a carrier tape in which electronic components are stored; and the cover tape joined to the carrier tape to seal the electronic components.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a cover tape is provided that suppresses lifting at the time of heat sealing.

Drawings

The foregoing and other objects, features and advantages will be apparent from the following description of preferred embodiments, taken in conjunction with the accompanying drawings.

Fig. 1 is a cross-sectional view showing the structure of a cover tape of the present embodiment.

Fig. 2 is a view showing an example of a state in which the cover tape for electronic component packaging of the present embodiment is sealed to a carrier tape.

Fig. 3 is a schematic diagram showing the amount of lifting of the cover tape after heat sealing.

Detailed Description

As shown in fig. 1, the electronic component packaging cover tape 10 of the present embodiment includes a base material layer 3 and an intermediate layer 1 provided on one surface of the base material layer 3. The cover tape 10 may have a two-layer structure of the base layer 3/the intermediate layer 1, or may have a multilayer structure of the base layer 3/the intermediate layer 1/the sealant layer 2 in which the sealant layer 2 is laminated on the intermediate layer 1.

A method of using a cover tape is described herein with reference to fig. 2. As shown in fig. 2, the cover tape 10 is used as a cover material for the carrier tape 20 in which concave-shaped pockets 21 are continuously provided corresponding to the shape of the electronic components. Specifically, cover tape 10 is used in such a manner as to be bonded (e.g., heat-sealed) to the surface of carrier tape 20 so as to cover the entire opening portions of pockets 21 of carrier tape 20. In the following description, a structure obtained by joining cover tape 10 to carrier tape 20 is referred to as electronic component package 100.

In an electronic device manufacturing site, electronic components are housed in pockets 21 of a carrier tape 20, and then a cover tape 10 is bonded to the surface of the carrier tape 20 so as to cover the entire opening portions of the pockets 21 of the carrier tape 20, thereby producing a package 100 housing the electronic components. As described above, the package 100 is transported to a work area where surface mounting is performed on an electronic circuit board or the like while being wound on a paper or plastic reel. In the surface mounting process of the electronic component, the cover tape 10 is peeled off from the carrier tape 20, and the electronic component is automatically taken out from the package and mounted on the electronic circuit board.

The cover tape 10 of the present embodiment is joined to the carrier tape 20 such that the intermediate layer 1 is located on the electronic component side. The joining of the cover tape 10 to the carrier tape 20 is performed by heating at a temperature of about 180 ℃ using a heat sealing iron. As shown in fig. 3, floating at the time of heat-sealing means that the cover tape 10 expands to the side opposite to the carrier tape 20 side. The reduced floating means that the cover tape 10 has a small degree of swelling, which is defined by the floating amount 30 in fig. 3.

In the cover tape 10 of the present embodiment, when the dimension of the intermediate layer 1 at 23 ℃ is T0 and the dimension after heating at 80 ℃ for 2 hours is T1, the dimensional change rate in the flow direction (MD direction) of the intermediate layer 1 represented by the following formula (1) is-4% to 4%, and the dimensional change rate in the width direction (TD direction) is 0% to 2%,

the dimensional change rate (%) [ (T0-T1)/T0] × 100 formula (1).

The dimensional change rate of the intermediate layer 1 at 80 ℃ is an indicator of the degree of dimensional change of the cover tape 10 caused by heat when a heat sealing iron is brought close. If the dimensional change rate of the intermediate layer 1 at 80 ℃ is within the above range, the swelling of the cover tape 10 due to heat when a heat-sealing iron is brought close can be suppressed, and therefore, the floating of the cover tape 10 at the time of heat-sealing can be suppressed. The degree of flotation of the cover tape 10 can be evaluated in terms of the amount of flotation 30 shown in fig. 3. The intermediate layer 1 has a dimensional change rate in the MD direction of-4% to 4%, preferably-2% to 2%, at 80 ℃. The intermediate layer 1 has a dimensional change rate in the TD direction at 80 ℃ of 0% to 2%, preferably 0.1% to 1%. The cover tape 10 including the intermediate layer 1 has excellent dimensional stability, and since dimensional change due to heating is suppressed when a heat-sealing iron is brought close, the floating amount 30 when heat-sealed to the carrier tape 20 is small, and it is possible to prevent the electronic components housed in the carrier tape 20 from being protruded or rotated.

Dimensional changes caused by heating of the cover tape 10 can be controlled by adjusting the rate of dimensional change of the intermediate layer 1 at 80 ℃. When the cover tape 10 is produced from the intermediate layer 1 and the base layer 3 which is generally used in this field, the floating amount 30 of the cover tape 10 when heat-sealed to the carrier tape 20 can be controlled to be 0 μm or more and 40 μm or less by using the intermediate layer 1 having the above dimensional change characteristics.

When the cover tape 10 is produced by laminating the intermediate layer 1 and the sealant layer 2 on the base layer 3 or when the cover tape 10 is joined to the carrier tape 20, the base layer 3 may have mechanical strength to such an extent that it can withstand stress applied to the cover tape 10 and heat resistance to such an extent that it can withstand the thermal history at the time of heat sealing. The form of the material constituting substrate layer 3 is not particularly limited, but it is preferably processed into a film form from the viewpoint of ease of processing.

In one embodiment, the base layer 3 is made of a thermoplastic resin, and a film, particularly a biaxially stretched film, formed of a thermoplastic resin such as a polyester resin, a polyamide resin, a polyolefin resin, a polyacrylate resin, a polymethacrylate resin, a polyimide resin, a polycarbonate resin, or an ABS resin can be suitably used. Preferably, a biaxially stretched polyethylene terephthalate film, and any commercially available film can be used. The thickness of the base material layer 3 is usually 5 μm or more and 50 μm or less.

As the substrate layer 3, a substrate layer coated or kneaded with an antistatic agent for antistatic treatment, or a substrate layer subjected to corona treatment, easy-to-bond treatment, or the like may be used.

The dimensional change rate of the intermediate layer 1 can be controlled by appropriately selecting the material, the composition of the material, the thickness, the manufacturing method, and the like of the intermediate layer 1.

The intermediate layer 1 is preferably a film obtained by film-forming a resin composition containing at least one selected from a polyethylene resin and a polypropylene resin by inflation. Examples of the polyethylene resin used in the intermediate layer 1 include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, ethylene-acrylic ester random copolymer resins such as ethylene-methyl acrylate, ethyl acrylate, propyl acrylate, and n-butyl acrylate, and ethylene-vinyl acetate random copolymer resins. As the ethylene-acrylate random copolymer resin and the ethylene-vinyl acetate random copolymer resin, resins containing 99 mass% or less and 50 mass% or more of ethylene units can be used. When the ethylene ratio is 50 mass% or more, the intermediate layer 1 is soft, and the pressure unevenness of the heat-sealing iron at the time of heat-sealing can be dispersed, which is preferable. Such a dimensional change at the time of heat sealing of the intermediate layer 1 is small, and therefore, is preferable. The thickness of the intermediate layer 1 is preferably 10 μm or more and 30 μm or less.

Examples of the polypropylene resin include polypropylene obtained by polymerizing propylene alone, and ethylene-propylene random copolymer resins.

When the sealant layer 2 is used, the sealant layer 2 is made of a thermoplastic resin exhibiting easy peelability to the carrier tape 20 and easily peelable therefrom in use, and for example, a mixture of 1 or more resins selected from ethylene polymers such as polyethylene resins, ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, and ethylene-butene-1 random copolymers, and 1 or more resins selected from styrene polymers such as styrene-butadiene copolymers, polystyrenes, and impact polystyrenes, and the like can be used. Among them, a mixture of an ethylene-butene-1 random copolymer, a styrene-butadiene copolymer and high impact polystyrene is preferable from the viewpoint of continuous stability of peel strength when peeled off by heat-sealing to the carrier tape 20. The thickness of the sealant layer 2 is preferably 0.2 μm or more and 40 μm or less, and more preferably 0.3 μm or more and 30 μm or less. When the thickness of the sealant layer 2 is less than 0.2 μm, it is difficult to obtain sufficient peel strength at the time of heat sealing, while when the thickness of the sealant layer 2 is more than 40 μm, it is easy to cause limitations in use, and for example, it is necessary to set the temperature of a sealing iron used for heat sealing to be high, or to set the time required for the sealing iron to be in contact with the heat sealing iron to be long, or the like.

The method of manufacturing the cover tape 10 of the present embodiment is not particularly limited, and a manufacturing method generally used in the art can be used. For example, the base layer 3, the intermediate layer 1, and the sealant layer 2, which are biaxially stretched films, are prepared in advance, and the layers may be laminated by a dry lamination method or an extrusion lamination method. In either case, a tie coat agent may be applied between the layers as necessary. As the anchor coat agent, polyurethane or polyolefin, ethylene-vinyl acetate resin, ethylene-acrylate resin, vinyl chloride-vinyl acetate, polyethyleneimine, or the like can be used. The method of applying the anchor coat agent is also not particularly limited, but a commonly used roll coater, gravure coater, reverse roll coater, bar coater, die coater, or the like can be used as the coater. In the extrusion lamination method, a molten polyethylene resin layer (sand resin layer) may be provided between the respective layers by T-die extrusion or the like as necessary within a range not affecting the effect of the present invention.

The sealant layer 2 is produced by mixing the respective resins and additives constituting the sealant layer 2 with a mixer such as a henschel mixer, a tumbler mixer, or a mortar mixer (マゼラー), extruding them, and directly forming a film by a casting method, or by melt-kneading the above mixture with a kneading extruder such as a single-shaft or twin-shaft or planetary extruder to form pellets, and further forming a film by a general method such as a T-die method, an inflation method, a casting method, or a calendering method.

Alternatively, the cover tape 10 of the present embodiment may be formed by melt-kneading the resin constituting the sealant layer 2 and the resin constituting the intermediate layer 1 using separate uniaxial or biaxial extruders, laminating and integrating the two via a feeding mechanism or a multi-manifold die, and then co-extruding the two layers by a T-die method or an inflation method, thereby forming a two-layer film composed of the sealant layer 2 and the intermediate layer 1, and laminating the surface of the two-layer film on the intermediate layer 1 side with the base layer 3 by the dry lamination method or the extrusion lamination method. This method has an advantage that adhesion of the inner and outer surfaces of the film, so-called blocking, can be easily prevented when the film formed is wound up, and the sealant layer 2 can be made thinner.

The cover tape 10 produced by the above-described method can also be slit according to the intended use.

The thickness of the entire cover tape 10 of the present embodiment can be appropriately set in the range of 40 μm to 90 μm. In the case where the thickness of the entire cover tape 10 is less than 40 μm, the cover tape 10 is thin, and therefore, the strength of the cover tape is insufficient and handling is difficult, and the cover tape 10 is easily broken when peeled. On the other hand, if the thickness of the entire cover tape 10 is greater than 90 μm, heat sealing tends to be difficult. The width of the cover tape 10 is preferably 1mm or more and 100mm or less.

[ examples ]

The present invention is described with reference to examples, but the present invention is not limited to these examples.

(example 1)

Manufacturing a cover tape: as the substrate layer, a biaxially stretched polyethylene terephthalate film (Toyo Boseki Co., Ltd., T6140) having a thickness of 25 μm was prepared. Polyethylene (manufactured by Kohyo Co., Ltd.: LM-015) was laminated as an intermediate layer on the base material layer so that the thickness thereof became 25 μm. After the corona treatment of the intermediate layer, an acrylic sealant resin (a 450A, manufactured by japan ink corporation) as a sealant layer was formed into a film so that the thickness thereof became 2 μm, thereby obtaining a cover tape having a layer structure shown in fig. 1.

The dimensional change rate of the polyethylene layer serving as the intermediate layer was measured by the following method. First, the polyethylene film as the intermediate layer was cut into 400mm square pieces at 23 ℃ under an atmosphere of 50% relative humidity. The test film was set to a size of T0. After the test film was heated in an oven set at 80 ℃ for 2 hours, the film was taken out, and the dimensions corresponding to the flow direction and the width direction were measured, respectively, to obtain T1. The dimensional change rate in each direction was calculated from the following formula (1). The results are shown in table 1 below,

the dimensional change rate (%) [ (T0-T1)/T0] × 100 formula (1).

Comparative example 1

Manufacturing a cover tape: as the substrate layer, a biaxially stretched polyethylene terephthalate film (Toyo Boseki Co., Ltd., T6140) having a thickness of 25 μm was prepared. Polyethylene (Idemitsu Unitech co., ltd.: L S-711C) was laminated as an intermediate layer on the base layer so that the thickness thereof became 25 μm. After the corona treatment of the intermediate layer, an acrylic sealant resin (a 450A, manufactured by japan ink corporation) as a sealant layer was formed into a film so that the thickness thereof became 2 μm, thereby obtaining a cover tape having a layer structure shown in fig. 1.

the dimensional change rate (%) [ (T0-T1)/T0] × 100 formula (1).

(measurement of the amount of lifting of cover tape)

The cover tapes obtained in example 1 and comparative example 1 were each cut into a width of 5.5mm, and heat-sealed on a carrier tape having a width of 8mm under the following conditions.

Iron shape at sealing: blade width of 0.3 mm/blade length of 54 mm/blade interval of 1.95mm

Sealing temperature: 180 deg.C

Sealing time: 50ms

Sealing pressure: 4kgf

Thereafter, the amount of lifting of the cover tape was measured. The results are shown in table 1 below.

(evaluation of rotation with and without electronic Components)

The cover tapes of example 1 and comparative example 1 cut out to a width of 5.3mm were heat-sealed to a carrier tape containing electronic components having the following dimensions in a bag, to obtain an electronic component package.

Pocket size of carrier tape: 0.35mm (length) × 0.65mm (width) × 0.35mm (height)

Size of electronic component: 0.3mm (length) × 0.6mm (width) × 0.3mm (height)

Vibration was applied to the package at 600rpm for 1 minute, the cover tape was peeled from the package, and the state of the electronic component was visually checked to determine whether the electronic component rotated. The number of rotated electronic components was counted, and the number of rotated components in 1000 samples was shown in table 1 below.

[ Table 1]

	Example 1	Comparative example 1
			Thickness of substrate layer (μm)	25	25
Thickness of the intermediate layer (μm)	25	25
			Thickness of sealant layer (μm)	2	2
MD-directional dimensional Change Rate (%) of intermediate layer at 80 deg.C	-1.3	-2.0
			Dimension change rate in TD direction of intermediate layer at 80 ℃ (%)	+0.30	-0.55
< evaluation result >
			Amount of float (μm) at 180 ℃ when the cover tape was sealed	20	60
Rotation of parts (number of 1000)	0 number of	10 are provided with

The cover tape of example 1 had a reduced amount of floating when heat sealed to a carrier tape. Therefore, the rotation of the electronic component accommodated in the carrier tape is suppressed.

This application claims priority based on japanese application patent No. 2017-122192, filed on 22/6/2017, the disclosure of which is incorporated herein in its entirety.

Claims

1. A cover tape for packaging electronic components,

the cover tape has a two-layer structure comprising a base material layer and an intermediate layer laminated on one surface of the base material layer or a three-layer structure comprising a base material layer, an intermediate layer and a sealant layer laminated in this order,

the intermediate layer is an inflation film of a resin composition comprising at least 1 resin selected from the group consisting of polyethylene resins and polypropylene resins,

when the dimension of the intermediate layer at 23 ℃ is T0 and the dimension after heating at 80 ℃ for 2 hours is T1, the rate of dimensional change in the intermediate layer in the flow direction, i.e., in the MD direction, is-2% or more and 2% or less, and the rate of dimensional change in the width direction, i.e., in the TD direction, is 0.1% or more and 1% or less,

the dimensional change rate (%) [ (T0-T1)/T0] × 100 formula (1).

2. The cover tape of claim 1,

the substrate layer has a thickness of 5 [ mu ] m or more and 50 [ mu ] m or less.

3. The cover tape of claim 1,

the intermediate layer has a thickness of 10 [ mu ] m or more and 30 [ mu ] m or less.

4. The cover tape of claim 1,

the sealant layer has a thickness of 0.2 μm or more and 40 μm or less.

5. The cover tape of any one of claims 1-4,

the cover tape has a width of 1mm or more and 100mm or less.

6. An electronic component package comprising:

a carrier tape in which electronic parts are stored, and

the cover tape of any one of claims 1 to 5 joined to the carrier tape in such a manner as to seal the electronic components.