JP2005014916A - Cover tape for packaging electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cover tape in which there exists no possibility of generating such a trouble as crease generation during a winding process in manufacturing as it is excellent in surface lubricating properties, and releasing strength is appropriate and a difference between the maximum value and the minimum value of the releasing strength is small. <P>SOLUTION: The cover tape for packaging the electronic component is a cover tape heat-sealable on a plastic carrier tape on which storing pockets for storing the electronic components are stored are continuously formed, and is characterized by that the cover tape comprises a biaxially oriented film (a layer A) being either one of a polyester, a polypropylene or a nylon, and a thermoplastic resin layer (a layer B) prepared by mixing 10-90 pts.wt. styrene copolymer and 0.01-10 pts.wt. silicon dioxide to 100 pts.wt. ethylene copolymer on one face of the layer A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００１５】
比較例４は層Ｂ以外は実施例５および６と同組成であるが、比較例４にあるようにメタクリル酸エステル共重合体のＥＥＡに対する添加部数が１００重量部では製膜が出来なかった。
【００１６】
表１中の記号は以下の通りである。
ＰＥＴ ：ポリエチレンテレフタレート
ＰＰ ：ポリプロピレン
ＰＳ ：ポリスチレン
ＭＳ ：メタクリル酸メチル− スチレン共重合体
Ｎｙ ：ナイロン
Ｏ− ：二軸延伸の意味
ＬＤＰＥ ：低密度ポリエチレン
ＥＶＡ ：エチレンー酢酸ビニル共重合体
ＥＥＡ ：エチレンーエチルアクリレート共重合体
ＥＭＭＡ ：エチレンーメチルメタクリレート共重合体
ＡＤ ：接着性樹脂（ポリエチレン酸変性物）
ＤＬ ：ドライラミネート接着剤層
ＳｉＯ２ ： 二酸化ケイ素
【００１７】
【発明の効果】
本発明に従うと、２軸延伸したポリエチレンテレフタレートを対象にした層Ｂの摩擦係数が４未満になる様に積層されている為、フィルムの滑性に優れ、これまでよりフィルム製造時の巻取り等の面での加工性が向上する。
また、剥離強度が強すぎず弱すぎず、また、剥離強度の最大値と最小値の差が小さくなる様、制御できる為、実装工程における剥離強度によるトラブルを防止できる。
【図面の簡単な説明】
【図１】本発明のカバーテープの基本の層構成を示す断面図である。
【図２】本発明の実施例及び比較例にあげた共押出法により作製したカバーテープの層構成を示す断面図である。
【符号の説明】
１：カバーテープ
２：層Ａ（二軸延伸フィルム層）
３：層Ｂ（熱可塑性樹脂シール層）
４：層Ｃ（層Ｂを除く共押出層）
５：層Ｄ（接着層）[0001]
[Technical field to which the invention belongs]
The present invention relates to a plastic carrier in which a storage pocket is formed out of a package that has functions of protecting electronic components from contamination and arranging and taking them out for mounting on an electronic circuit board when storing, transporting and mounting the electronic components. The present invention relates to a cover tape that can be sealed to a tape.
[Prior art]
In recent years, surface mount electronic components such as ICs, transistors, diodes, capacitors, piezoelectric element resistors, etc., are made of plastic with a continuous embossed pocket that can be accommodated according to the shape of the electronic components. The carrier tape and the cover tape that can be sealed with the carrier tape are packaged and supplied. The electronic components of the contents are automatically taken out after the cover tape of the package is peeled off and mounted on the surface of the electronic circuit board. At that time, if the difference between the maximum value and the minimum value of the peel strength is large, the carrier tape may be undulated and the electronic component may be ejected, or if the peel strength is too strong, the cover tape may be cut. On the other hand, if the peel strength is too weak, the cover tape is peeled off before reaching the mounting process, and the electronic component falls off. In order to overcome these problems, a method for adjusting the seal strength by using cohesive peeling is described in Patent Document 1, but if the cover tape has low surface slipperiness, it cannot be wound well when manufacturing the cover tape. Problems occur. Therefore, a cover tape with better slipperiness is required from the viewpoint of workability.
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 08-192886 [0004]
[Problems to be solved by the invention]
The present invention provides a cover tape excellent in surface slipperiness with an appropriate peel strength and a small difference between the maximum and minimum peel strengths to prevent the above-mentioned troubles.
[0005]
[Means for Solving the Problems]
The present invention is (1) a cover tape that can be heat-sealed to a plastic carrier tape in which storage pockets for storing electronic components are continuously formed, and the cover tape is one of polyester, polypropylene, and nylon. A thermoplastic film in which an axially stretched film (layer A) and one side of layer A are mixed with 10 to 100 parts by weight of styrene copolymer and 0.01 to 10 parts by weight of silicon dioxide with respect to 100 parts by weight of ethylene copolymer. A cover tape for packaging electronic parts, characterized by having a resin layer (layer B);
(2) The cover tape for packaging electronic parts according to (1), wherein the friction coefficient of the layer B with respect to the surface of the layer A is less than 4.
(3) The electronic component according to (1) or (2), wherein at least one layer selected from the group consisting of a polyester layer, a nylon layer and a polypropylene layer is laminated between the layer A and the layer B. Cover tape for packaging,
(4) The copolymer component of the ethylene copolymer contained in the layer B is one selected from the group consisting of vinyl acetate, acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester and ionomer (1) (2) or the cover tape for packaging electronic parts as described in (3),
(5) The copolymer component of the styrene copolymer contained in layer B was selected from the group consisting of butadiene, ethylene, butylene, propylene, isoprene, styrene, acrylic acid, acrylic acid ester, methacrylic acid, and methacrylic acid ester. Electronic component packaging cover tape according to claim 1, 2 or 3, which is one type or a combination thereof, (1) (2) (3) or (4) electronic component packaging cover tape,
(6) The cover tape for packaging electronic parts according to (1) to (5), wherein the copolymerization ratio of the ethylene copolymer contained in layer B is 10 to 90 parts by weight with respect to 100 parts by weight of ethylene,
(7) The cover tape for packaging electronic components according to (1) to (6), wherein the thickness of the layer B is 0.5 to 50 μm,
(8) After the heat-sealing of the cover tape and the carrier tape, the strength when the cover tape is peeled from the carrier tape is 0.1 to 1.3 N per 1 mm width. Cover tape for packaging electronic parts,
(9) After the cover tape is heat sealed with the carrier tape, the difference between the maximum value and the minimum value of the peel strength when the cover tape is peeled from the carrier tape is 0.4 N or less per 1 mm width. (8) The electronic component packaging cover tape according to any one of the above,
It is.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
An example of the layer structure of the cover tape (1) of the present invention will be described with reference to FIGS. Layer A (2) is a biaxially stretched film of any one of a biaxially stretched polyester film, a biaxially stretched polypropylene film, and a biaxially stretched nylon film, and is a transparent and highly rigid film having a thickness of 6 to 100 μm. Two or more layers of the stretched film may be laminated to increase the mechanical strength of the cover tape.
[0007]
For layer B (3), 10 to 90 parts by weight of a non-adhesive component styrene copolymer was added and slippery in order to suppress variation in peel strength and smoothly peel off with respect to 100 parts by weight of ethylene copolymer. It is a thermoplastic resin sealing layer in which 0.01 to 10 parts by weight of silicon dioxide is mixed for improving the property.
If the number of mixed parts of silicon dioxide is less than 0.01 parts by weight with respect to 100 parts by weight of the ethylene copolymer, the dynamic friction coefficient exceeds 4, and the surface of the layer B has low lubricity, so wrinkles occur during winding. Trouble occurs. On the other hand, when the amount exceeds 10 parts by weight, the sealing property to the carrier tape is affected.
[0008]
The copolymer component contained in the ethylene copolymer is selected from any of vinyl acetate, acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester, and ionomer. Further, the copolymer component contained in the styrene copolymer is selected from any of butadiene, ethylene, butylene, propylene, isoprene, styrene, acrylic acid, acrylic acid ester, methacrylic acid, and methacrylic acid ester. When the added amount of the styrene copolymer is less than 10 parts by weight, it is difficult to remove the cover tape smoothly after the carrier tape and the cover tape are heat sealed. On the other hand, if it exceeds 90 parts by weight, the film becomes brittle and film formation cannot be performed.
The styrene component of the styrene copolymer may be variously selected, such as a high impact polystyrene (HIPS) system that includes a rubber component and has improved impact resistance, but a general-purpose polystyrene (GPPS) system is used in terms of transparency and thermal stability. desirable. The styrene copolymer used in the present invention is obtained by copolymerizing these styrene components and one copolymer component selected from the group consisting of acrylic acid, acrylic acid ester, methacrylic acid and methacrylic acid ester. It is done.
[0009]
As shown in Fig. 2, polyethylene, polyethylene copolymer, polyurethane adhesive or epoxy adhesive is bonded to layer C (coextruded layer excluding layer B) to increase adhesion strength with layer A. Layer D may be provided.
When the coextrusion method is selected as the method for forming the layer B, an unstretched polyester layer, nylon layer, or polypropylene layer may be laminated between the layer A and the layer B for the same purpose.
[0010]
The copolymerization ratio of the ethylene copolymer contained in the layer B is 10 to 90 parts by weight with respect to 100 parts by weight of ethylene.
If it is less than 10 parts by weight, the carrier tape can be heat-sealed, but after sealing, the peel strength tends to decrease with time, and may eventually peel off.
If it exceeds 90 parts by weight, the carrier tape can be heat-sealed, but after sealing, the peel strength tends to increase with time, and eventually it may not peel off. In addition, an ethylene copolymer having a copolymerization ratio exceeding 90 parts by weight has few products on the market and becomes a special product, leading to an increase in cost. The thickness of the layer B is desirably 0.5 to 50 μm. If it is less than 0.5 μm, the adhesion to the substrate is weakened and delamination occurs. Moreover, when it exceeds 50 micrometers, transparency will worsen and the visibility of the content will fall.
It is desirable that the strength when the cover tape is peeled from the carrier tape is 0.1 to 1.3 N per 1 mm width. If it is less than 0.1 N, it may peel off during conveyance after sealing. Moreover, when it exceeds 1.3 N, the substrate may be damaged when peeled off.
As the lamination method, co-extrusion, extrusion coating, and gravure coater are used.
[0011]
When the cover tape is peeled from the carrier tape, the difference between the maximum value and the minimum value of the peel strength is preferably 0.4 N or less per 1 mm width. When the difference between the maximum value and the minimum value of the peel strength exceeds 0.4 N, the peel strength varies greatly, causing a problem that the carrier tape undulates and the electronic component pops out at the time of peeling.
[0012]
【Example】
Examples of the present invention are shown below, but the present invention is not limited to these examples.
<< Examples and Comparative Examples >>
As shown in Table 1, the biaxially stretched film layer (layer A) and the coextruded layer (layer C and layer B) formed by the coextrusion method were dry laminated with the adhesive layer D, and shown in FIG. A cover tape having a layer structure was obtained.
The obtained cover tape was slit to a width of 5.5 mm, sealed with a carrier tape made of 8 mm width and 1 mm width at a seal temperature of 160 ° C., and the peel strength was measured. The coefficient of friction test was performed by a method based on JIS K7125.
[0013]
Table 1 shows the layer configuration and evaluation results for the examples and comparative examples.
The numbers on the right side of each example and comparative example indicate the thickness (unit: μm) of each layer, the ethylene copolymer column of layer B indicates the copolymer component of the ethylene copolymer, and the numbers in parentheses indicate the copolymerization. Indicates the ratio. The numbers in the methacrylic acid ester copolymer column indicate the type of the methacrylic acid ester copolymer and its added parts by weight with respect to 100 parts by weight of the ethylene copolymer. The symbol in the right frame below the peel strength indicates each unit.
In addition, the presence or absence of troubles (wrinkles, etc.) in the winding process during production was also described.
[0014]
[Table 1]

[0015]
Comparative Example 4 had the same composition as Examples 5 and 6 except for layer B, but as shown in Comparative Example 4, film formation could not be performed when the number of parts added to the EEA of the methacrylic ester copolymer was 100 parts by weight.
[0016]
The symbols in Table 1 are as follows.
PET: Polyethylene terephthalate PP: Polypropylene PS: Polystyrene MS: Methyl methacrylate-styrene copolymer Ny: Nylon O-: Meaning of biaxial stretching LDPE: Low density polyethylene EVA: Ethylene-vinyl acetate copolymer EEA: Ethylene-ethyl acrylate Copolymer EMMA: Ethylene-methyl methacrylate copolymer AD: Adhesive resin (polyethylene acid-modified product)
DL: Dry laminate adhesive layer SiO2: Silicon dioxide
【The invention's effect】
According to the present invention, since the layer B for the biaxially stretched polyethylene terephthalate is laminated so that the friction coefficient is less than 4, the film is excellent in slipperiness, and more easily wound during film production. This improves the workability of the surface.
In addition, since the peel strength is not too strong and not too weak, and the difference between the maximum value and the minimum value of the peel strength can be controlled, troubles due to the peel strength in the mounting process can be prevented.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a basic layer structure of a cover tape of the present invention.
FIG. 2 is a cross-sectional view showing a layer structure of a cover tape produced by a coextrusion method given in the examples and comparative examples of the present invention.
[Explanation of symbols]
1: Cover tape 2: Layer A (biaxially stretched film layer)
3: Layer B (thermoplastic resin sealing layer)
4: Layer C (coextruded layer excluding layer B)
5: Layer D (adhesive layer)

Claims (9)

A biaxially stretched film (layer A) which is a cover tape which can be heat-sealed on a plastic carrier tape in which storage pockets for storing electronic components are continuously formed, and which is either polyester, polypropylene or nylon ) And a thermoplastic resin layer (layer B) in which 10 to 90 parts by weight of styrene copolymer and 0.01 to 10 parts by weight of silicon dioxide are mixed with 100 parts by weight of ethylene copolymer on one surface of layer A A cover tape for packaging electronic parts, comprising: The cover tab for electronic component packaging according to claim 1, wherein the coefficient of dynamic friction of the layer B with respect to the surface of the layer A is less than 4. The cover tape for electronic component packaging according to claim 1 or 2, wherein at least one layer selected from the group consisting of a polyester layer, a nylon layer and a polypropylene layer is laminated between the layer A and the layer B. The copolymer component of the ethylene copolymer contained in the layer B is one selected from the group consisting of vinyl acetate, acrylic acid, acrylic ester, methacrylic acid, methacrylic ester and ionomer. 3. Cover tape for packaging electronic parts according to 3. The copolymer component of the styrene copolymer contained in the layer B is selected from the group consisting of butadiene, ethylene, butylene, propylene, isoprene, styrene, acrylic acid, acrylic acid ester, methacrylic acid, and methacrylic acid ester, or The cover tape for packaging electronic parts according to claim 1, 2, 3, or 4, which is a combination thereof. The cover tape for packaging electronic parts according to claim 1, wherein the copolymerization ratio of the ethylene copolymer contained in layer B is 10 to 90 parts by weight with respect to 100 parts by weight of ethylene. The cover tape for packaging electronic components according to claim 1, wherein the layer B has a thickness of 0.5 to 50 μm. 8. The cover tape for packaging electronic parts according to claim 1, wherein the strength when the cover tape is peeled off from the carrier tape after heat sealing the carrier tape is 0.1 to 1.3 N per 1 mm width. . The difference between the maximum value and the minimum value of the peel strength when the cover tape is peeled off from the carrier tape after heat sealing the carrier tape with the carrier tape is 0.4 N or less per 1 mm width. Cover tape for packaging electronic parts.

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