JPH1017015A - Cover tape for carrier of electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heat-weld by a sufficient bonding force regardless of the presence/ absence of a release treatment on a carrier tape, or the difference in material, etc., by forming an adhesive layer of a composition of which the major components are at least one kind of an ethylene-α olefin copolymer or an αolefin copolymer, and an ethylenevinyl acetate copolymer. SOLUTION: An adhesive layer 4 is formed of a composition of which the major components are at least one kind of an ethylene-α olefin copolymer or an α olefin copolymer, and an ethylene-vinyl acetate copolymer, and is formed by an affixing of films being formed in advance or an extrusion-coating. The adhesive layer 4 can avoid an unfavorable bonding due to an insufficient thickness, by the extrusion. Also, it is assumed that a required addition of a lubricant may unfavorably react to the adhesion, but the bonding force and the separation smoothness are improved by the mixing of the ethylene-α olefin copolymer or the α olefin copolymer, and the adhesive layer 4 is not affected by the material of a carrier tape made of a plastic or the presence/absence of a release treatment, and shows an excellent adhesion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cover for an electronic component carrier used for packaging and transporting electronic components such as ICs and capacitors mounted on a circuit board.

[0002]

2. Description of the Related Art To mount an electronic component such as an IC on a circuit board, the electronic component is packaged and transported to a mounting factory, the transporter is set on an automatic mounting machine, and the electronic component is transferred from the transporter to a vacuum nozzle. Picking up, centering, and mounting. As the electronic component carrier, electronic components are stored in a carrier tape pocket having pockets provided at equal intervals in a longitudinal direction on a plastic tape-shaped carrier, and the pocket is covered to form a carrier tape. Cover
A method of bonding an adhesive seal is known.

[0003] A cover tape of this type may be provided with a heat-sealing adhesive layer provided on one side of a support film. In this case, a pocket of a plastic carrier tape is used in a packaging factory. A cover tape is heat-sealed on a plastic carrier tape while accommodating electronic components, and the electronic components are picked up while peeling off the cover tape at an electronic component mounting factory. As the above-mentioned heat seal tape, an ethylene-vinyl acetate copolymer solution was applied to one surface of a plastic support film such as a biaxially stretched polyester tape and dried to form a heat-sealing adhesive layer. Things are known.

[0004]

However, the thickness of the adhesive layer formed by the coating method is small, and it is not easy to obtain a sufficient adhesive strength. In the molding of the above-mentioned plastic embossed carrier tape, the surface of the plastic tape is separated in order to enhance the releasability of the embossing roll die and to smoothly release the die during embossing. In some cases, a mold treatment, for example, a silicon release treatment, is performed. In the embossed carrier tape formed as described above, the release treatment film on the surface lowers the adhesive force with the cover tape. Thus, the adhesive layer of the thin ethylene-vinyl acetate copolymer formed by the above coating cannot be expected to have a predetermined adhesive strength.

[0005] Further, a carrier tape on which a peeling treatment film exists is provided.
Even if the cover tape is heat-sealed to the tape, the dispersion of the adhesive force becomes large, and when the cover tape is peeled off, the carrier tape vibrates violently and jumping travel of the electronic parts occurs. easy. Furthermore, in order to prevent the generation of static electricity due to friction at the peeling interface when the cover tape is peeled off, and to completely eliminate the trouble due to the electrostatic adhesion of the electronic parts, the carrier tape and the cover are removed. The tape is made to have an antistatic property, and an antistatic agent may be added to the adhesive layer. However, under such circumstances, further poor adhesion of the thin adhesive layer due to the above coating is inevitable. Further, in consideration of the fear of destruction due to electrostatic stress during the transport of the electronic component, the carrier tape and the cover tape are made conductive, and the adhesive layer is made by adding conductive particles to the electronic component. In some cases, electrostatic shielding may occur, but even under such circumstances, further adhesion failure of the thin adhesive layer due to the above-described coating is inevitable.

As a method of forming the adhesive layer, there is a method of forming a film by an inflation film forming method or a cast film forming method, and laminating the film on a supporting film. An adhesive layer can be formed. However, according to the study results of the present inventors, even if the above-mentioned ethylene-vinyl acetate copolymer adhesive layer of the cover tape is formed sufficiently thick (about 30 μm) by this film method, the above-mentioned case is obtained. Problems can hardly be resolved.

An object of the present invention is to provide a cover tape having an adhesive layer which is thermally fused to a plastic carrier tape having a pocket for accommodating an electronic component. Regardless of the presence or absence of the material and the difference in the material, and can be thermally fused with a sufficient adhesive force without being influenced by the addition of an antistatic agent or conductive particles to the adhesive, and the vibration of the plastic carrier tape. It is an object of the present invention to provide a cover for an electronic component carrier that can be smoothly peeled off while suppressing the occurrence of the problem.

[0008]

A cover tape for an electronic component carrier according to the present invention has a cover having an adhesive layer which is thermally fused to a plastic carrier tape having a pocket for storing electronic components. -In a tape, the adhesive layer is a laminate of a preformed film of a composition comprising ethylene-α-olefin copolymer or at least one of α-olefin copolymer and ethylene-vinyl acetate copolymer as main components. And a composition characterized by being formed by extrusion coating. A preferable composition of the adhesive is 20 to 90% by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 3 to 20% by weight, density 0.85~0.90g / cm ³ ethylene -α-olefin copolymer 0-60wt%, alpha-olefin copolymer having a density 0.87~0.92g / cm ³ 0
６０60% by weight and tackifier 5-30% by weight, and the adhesive layer may contain an antistatic agent or conductive particles.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing an example of a cover tape for an electronic component carrier according to the present invention.
In FIG. 1, 1 is a plastic support film,
Usually, a biaxially stretched polyethylene terephthalate film is used, and the thickness is 6 μm to 100 μm. 6 μm
Below, rigidity is poor and it is easy to be entangled, and when it is 100 μm or more, it is too hard and adhesiveness becomes unstable, and a preferable range is 12 to 50 μm. One surface of the support film may be subjected to a surface treatment such as a corona treatment as necessary, and the other surface may be coated with an antistatic agent, a conductive paint, or a release agent. Reference numeral 2 denotes an anchor coat layer, which is used to increase the bonding strength between the next layer 3 and the support film 1, and if the next layer 3 and the support film 1 can be directly bonded sufficiently firmly, this anchor The coat layer 2 can be omitted. Reference numeral 3 denotes an intermediate layer, which is used for adjusting the rigidity and thickness of the cover tape, for improving the bonding strength between the support film and the adhesive layer described below, and for supporting the support film and the anchor coat. It can be omitted depending on the material and thickness of the layer. For the intermediate layer 3, for example, a polyolefin resin such as polyethylene and ethylene-vinyl ester copolymer, a (meth) acrylic resin, a polyurethane resin, and a polyester resin can be used alone or in combination.

4 is an ethylene-α-olefin copolymer or at least one of α-olefin copolymers and ethylene-α-olefin copolymer.
An adhesive layer formed from a composition containing a vinyl acetate copolymer as a main component and formed by laminating a film formed in advance or by extrusion coating. A suitable formulation of this composition is 20-90% by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 3-20% by weight, and an ethylene-α-olefin copolymer having a density of 0.85-0.90 g / cm ^3. 0-60% by weight, density 0.87-0.92g /
α-olefin copolymer 0-60wt% of cm ^3, usually amount to total 100 parts by weight of tackifier 5-30 wt% (0.4
(Part by weight to about 0.1 part by weight) of a lubricant, and the α-olefin of the ethylene-α-olefin copolymer includes, for example, propylene, hexene-1, octene-1, and 4-methylpentene-1. The α-olefin of the α-olefin copolymer includes butene-1, 4-methylpentene-1 and the like. Examples of the tackifier include an aliphatic hydrocarbon resin and a cycloaliphatic hydrocarbon. There are resins, aromatic hydrocarbon resins, rosin resins, terpene resins, and the like. Examples of the lubricant include fatty acid amide.

The thickness of the adhesive layer 4 is 5 μm to 60 μm.
Preferably it is 10 μm to 60 μm. When the thickness is 5 μm or less, the adhesiveness is poor, and the anchoring property of the adhesive layer is poor in production, so that the residue of the adhesive layer tends to remain on the carrier tape side when the cover tape is peeled off. On the other hand, if the thickness is 60 μm or more, the adhesiveness is too strong, and the workability of peeling off the cover tape becomes a problem. An antistatic agent can be added to the adhesive layer 4 in order to prevent the generation of frictional static electricity during peeling. Examples of the antistatic agent include polyethylene glycol and derivatives thereof such as polyethylene glycol. Telluric surfactants can be used. The amount of the antistatic agent to be added is such that the surface resistance of the adhesive layer can be reduced to 10 ¹³ Ω / □ or less, and is usually 0.5% by weight to 5% by weight. When the content is 0.5% by weight or less, the antistatic effect is hardly satisfactorily achieved, and when the content is 5% by weight or more, remarkable sealing properties due to adhesion inhibition and bleed-out of the antistatic agent after covering tape bonding. Reduction is a problem.

In consideration of the fear of destruction of the electronic component due to electrostatic stress during the transport of the electronic component, the cover is made conductive by making the carrier tape and the cover tape conductive to shield the electronic component electrostatically. The tape and the carrier tape may be made conductive with a surface resistance of 10 ¹² Ω / □ or less. In this case, the adhesive layer also contains conductive particles (for example, one or more of carbon black, titanium oxide, tin oxide, zinc oxide, and metal-coated particles. The particle shape is spherical or elliptical. Although needle-like shape is used, strong shearing during extrusion molding, and the needle is advantageous) which can reduce the amount compared to the spherical surface resistance 10 ¹² Ω / □ is the following conductive Usually, the addition amount is 5 to 60% by weight, preferably 10 to 50% by weight. When the content is less than 5% by weight, it is difficult to reduce the surface resistance value to less than 10 ¹² Ω / □, and the content is 60% by weight.
In this case, the transparency and the adhesion of the cover tape are inhibited.

A cover for an electronic component carrier according to the present invention.
In the coating, one or both of the anchor coat layer 2 and the intermediate layer 3 can be omitted, and the adhesive layer 4 can be formed by a preformed film or by extrusion coating. Thus, it can be manufactured by various methods according to the selection. For example, a method in which an adhesive film preformed by an inflation film molding method or a cast film molding method is bonded to an anchor-treated support film, the intermediate layer is melt-extruded by an extrusion coating molding machine, and the support film or the anchor film is formed. A method in which the intermediate layer during the extrusion is pulled out by sandwich lamination with the treated support film and the preformed adhesive film, a solvent solution of the resin for the intermediate layer, or dispersion of an emulsion or dispersion in the support film. A method in which the liquid is applied with a reverse coater, a gravure coater, or the like, dried to form an intermediate layer, and the above-mentioned pre-formed adhesive film is bonded to the intermediate layer. Is directly coated by melt extrusion, the intermediate layer is directly formed on the support film by melt extrusion. - After coating, direct co by melt extrusion of an adhesive layer - a method of coating, can be manufactured by a method such as molding by coextrusion intermediate layer and the adhesive layer on the support film.

A cover for an electronic component carrier according to the present invention.
In the packing, the electronic parts are heat-sealed on a plastic carrier tape containing the electronic parts at the packaging factory, and are peeled off and picked up at the electronic parts mounting factory. In the cover tape according to the present invention, since the adhesive layer is formed to be sufficiently thick by extrusion, it is possible to avoid poor adhesion due to insufficient adhesive thickness. It is necessary, and it is presumed that this lubricant adversely affects the adhesive force due to the tackiness suppressing effect or the releasing effect. However, in the cover tape according to the present invention, as is clear from the comparison between the following examples and comparative examples, the material of the plastic carrier tape and the release treatment of the plastic carrier tape are not limited. It exhibits excellent adhesion regardless of the presence or absence, and can be smoothly peeled from a plastic carrier tape while preventing vibration. That is, compared to the ethylene-vinyl acetate copolymer with a lubricant added,
Adhesive strength and peeling smoothness are remarkably improved by mixing the ethylene-α-olefin copolymer or the α-olefin copolymer. It is presumed that such a good result largely depends not only on the surface energy state that determines the wettability of the adhesive but also on diffusion and dissolution at the interface.

[0015]

【Example】

 Example 1 Biaxially stretched polyethylene tele having a thickness of 16 μm
Isocyanate-based anchor on one side of phthalate film
Apply a coating agent and dry it.
High density polyethylene (Mitsui Petrochemical Co., Ltd. product, Miraso
10P) is melt-extruded to form an intermediate layer having a thickness of 20 μm.
And extrude an adhesive of the following composition with a thickness of 30 μm.
To obtain a cover tape. Adhesive composition: ethylene-vinyl acetate content 6% by weight
Vinyl acetate copolymer (Mitsui Petrochemical Co., Ltd. product, Mira
Son 252) 42% by weight, density 0.88 g / cm ^ThreeEtch
Len-butene-1 copolymer (manufactured by Mitsui Petrochemical Co., Ltd.)
Product, tougher 4085) 42% by weight, as tackifier
Alicyclic hydrocarbon resin with a softening point of 125 ° C (Arakawa Chemical Co., Ltd.)
Formula company product, Alcon P-125) 16% by weight, 1 or more
0.2 parts by weight of fatty acid amide as a lubricant based on 00 parts by weight
Parts added.

Example 2 The composition of the adhesive was 65% by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 14% by weight (manufactured by Du Pont-Mitsui Polychemicals, Evaflex P-1407). Density 0.90g /
butene-1 copolymer cm ³ (Mitsui Petrochemical Co. Products, views - Ron BT-027) 15 wt%, the softening point of the tackifier 125 ° C. alicyclic hydrocarbon resin (Arakawa Chemical Co., Ltd. Product , Alcon P-125) 20% by weight or more, 100 parts by weight or more of 0.2% fatty acid amide as a lubricant.
Example 1 was the same as Example 1 except that the addition of parts by weight was used.

[Embodiment 3] Compared to Embodiment 1, the adhesive 10
0 parts by weight of a nonionic antistatic agent as an antistatic agent (manufactured by Kao Corporation, Electrostripper-TS-3)
Same as Example 1 except that 2 parts by weight of B) was added.
The surface resistance of this adhesive layer was 2 × 10 ¹² Ω / □. Example 4 The same as Example 1 except that 100 parts by weight of a metal-coated powder (product of Nippon Chemical Industry Co., Ltd., Bright 60NR) was added as conductive powder to 100 parts by weight of the adhesive. did. The surface resistance value of this adhesive layer was 3 × 10 ¹⁰ Ω / □.

Comparative Example The composition of the adhesive was 80% by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 6% by weight (manufactured by Mitsui Petrochemical Co., Ltd., Mirason 252), and the softening point as a tackifier was used. 125 ° C alicyclic hydrocarbon resin (Arakawa Chemical Co., Ltd., Alcon P-125)
The same procedure as in Example 1 was carried out except that fatty acid amide was added as a lubricant in an amount of 0.2 part by weight to 16 parts by weight, 100 parts by weight or more.

For each of these examples and comparative examples (both having a cover tape width of 9.5 mm), a polystyrene carrier tape (one without surface release treatment and one with silicon release treatment) were used. ones) and polyethylene terephthalate - DOO made carrier tape - flop (one without a surface release treatment to that of the silicone release treatment) of after adhered at the 180 ° C. × 0.3 sec × 3 kg / cm ² conditions, respectively Then, peeling was performed at 300 mm / min, the peeling force (adhesive force) at that time was measured, and the smoothness of the peeling was evaluated. No residue was observed on the carrier tape). In addition, [ス] indicates that the film could be peeled smoothly without being caught, and [x] indicates that the film was caught during the peeling.

[0020]

[Table 1]

[0021]

According to the cover for an electronic component carrier of the present invention, an antistatic agent or a conductive agent is applied to the adhesive regardless of whether or not the plastic carrier tape is subjected to a release treatment. Can be heat-sealed with sufficient adhesive strength to plastic carrier tape without being affected by the addition of conductive particles.
Since the peeling can be performed smoothly, the electronic component can be safely transported, and the safely transported electronic component can be picked up without a jumping travel in the mounting process.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of a cover tape for an electronic component carrier according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support film 2 Anchor coat layer 3 Intermediate layer 4 Adhesive layer

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Ichiro Nakano 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation

Claims (6)

[Claims] 1. A cover tape having an adhesive layer which is heat-sealed to a plastic carrier tape having a pocket for accommodating an electronic component, wherein the adhesive layer comprises an ethylene-α-olefin copolymer or α-olefin. A cover tape for an electronic component carrier, wherein the cover tape is formed of a composition containing at least one copolymer and an ethylene-vinyl acetate copolymer as main components. 2. An ethylene-α olefin copolymer or α
The adhesive layer is formed of a film preformed from a composition containing at least one olefin copolymer and an ethylene-vinyl acetate copolymer as main components.
A cover tape for an electronic component carrier according to the above. 3. An ethylene-α olefin copolymer or α
The cover for an electronic component carrier according to claim 1, wherein the adhesive layer is formed by extrusion coating of a composition containing at least one olefin copolymer and an ethylene-vinyl acetate copolymer as main components. - 4. The composition according to claim 1, wherein the composition of the adhesive is 20 to 90% by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 3 to 20% by weight and a density of 0.85 to 0.90 g.
/ Cm ³ ethylene -α-olefin copolymer 0-60wt%, density 0.87～0.92G / cm ³ of α-olefin copolymer 0-60wt%, 5 to 30 wt% tackifier A cover tape for an electronic component carrier according to claim 1. 5. A cover tape for an electronic component carrier according to claim 1, wherein the adhesive layer contains an antistatic agent. 6. A cover tape for an electronic component carrier according to claim 1, wherein the adhesive layer contains conductive particles.