JPH05201467A - Taping packaging material - Google Patents

Abstract

PURPOSE:To provide a taping packaging material consisting of a seal tape, which displays an excellent antistatic ability for a long period of time, and an embossed tape, in order to meet the tendency of a high integration of a small sized electronic component such as IC. CONSTITUTION:For a taping packaging material for small sized electronic components, a seal tape is constitued of a four layer structure with a base film layer 11, a heat sealable sealant layer 12 which is formed on the surface on the embossed tape side of the base film layer, a conductive innermost layer 13 including a tetracyanoquinodimethane complex which is formed on the surface of the heat sealable sealant layer, and a conductive outermost layer 14 including the tetracyanoquinodimethane complex which is formed on the other surface of the base film layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a taping packaging material composed of a sealing tape and an embossing tape for packaging a small electronic component. More specifically, the present invention completely prevents electrostatic breakdown of packaged items by forming conductive thin film layers on both the outermost and innermost surfaces of the sealing tape of the taping packaging material. The present invention relates to a taping packaging material.

[0002]

2. Description of the Related Art Recently, semiconductors, resistors, capacitors,
With the promotion of chipping of electronic parts such as coils, we have efficient taping packaging technology related to mass production of these electronic parts, automatic insertion machine for their packages, and automatic take-out machine at the time of use. Is required. As is well known, in this type of chipped packaging of small electronic components, an embossed tape (carrier tape) having a concave portion for accommodating the electronic component and the electronic component accommodated in the concave portion of the embossed tape. And a seal tape (cover tape) for sealing the recess. The edge of the embossed tape may be provided with a feed hole for convenience of automatic loading and unloading of these electronic components. Further, these taping packages are wound around a taping reel and stored and transported.

A particular problem in this type of taping package is how to protect various miniaturized and high-performance electronic components from electrostatic (electrostatic) damage. In particular, recently, the degree of integration of ICs (integrated circuits) has advanced to extremely high density (1 mega, 4 mega,
(16 megabits, etc.), and along with this, the problem of electrostatic breakdown of electronic components has become extremely important.

There are various known static electricity generating mechanisms for inducing electrostatic breakdown. For example, in the process of separating and separating two objects in contact with each other, the charge is reduced as the capacitance decreases. It shows a very high potential, and if the two objects are insulators, the electric double layer charge will remain. Therefore, in taping packaging, the peeling tape has a peeling angle of 170 to 180 ° and a peeling speed of 120 mm /
Therefore, it is required that the peeling charge be instantly at zero volt (0 V) when peeling under the condition of a normal temperature environment. Further, as a matter of course, excellent antistatic ability is also required on the embossed tape side.

Conventionally, various seal tapes (cover tapes) have been proposed for the purpose of reducing the above-mentioned peeling charge. For example, a hot-melt adhesive layer in which SnO ₂ is vapor-deposited on a base film such as PET (polyethylene terephthalate) to form a conductive layer, and an antistatic agent is kneaded on the embossed tape side via a primer layer. Formed one, or one in which a base film such as PET is coated with an antistatic agent and a hot-melt adhesive layer is formed by kneading the antistatic agent through the adhesive layer on the embossed tape side. It has been known.

However, in the antistatic technology for these sealing tapes, the former SnO ₂ vapor deposition method requires a complicated process of vapor deposition means, and the production cost becomes high. In the latter case where the base film is coated with an antistatic agent, the antistatic agent used may be an organic low molecular weight compound such as a surfactant, and may be ethyl silicate (Si (OEt)). ₄ ) Partial hydrolyzate, specifically, a high molecular weight polysiloxane-based one having a semi-permanent antistatic ability such as Colcoat P (manufactured by Colcoat Co., Ltd.) (having a Si-O-Si bond) ) Is used, but it is not sufficiently satisfactory in view of the antistatic ability required for this type of sealing tape. A polysiloxane-based antistatic agent is preferable because it is coated on the surface of a base film such as PET to form a strong inorganic antistatic film, but the back surface side of the base film in contact with the embossed tape is preferable. When a similar coating film is formed on the above, it is extremely difficult to directly (directly) form an adhesive layer for adhering with the embossed tape on this thin film because the coating film is an inorganic thin film. Is.

[0007] Further, Japanese Utility Model Application Laid-Open No. 11-12599 proposes a sealing tape for packaging a chip type electronic component using a tetracyanoquinodimethane complex known as a conductivity imparting substance. The outline of the sealing tape of this product is that the inner layer is a heat-sealable adhesive layer and the middle layer is PET.
It has a three-layer structure of a biaxially stretched film layer such as (polyethylene terephthalate) and a semiconductive layer in which the outermost layer uses the above-mentioned tetracyanoquinodimethane complex. Needless to say, the heat-sealable adhesive layer of the inner layer of the seal tape is heat-sealed on the embossed tape (carrier tape) side to package the chip-type electronic component.

[0008] However, the actual Kai 1-11-1259
The seal tape having the structure proposed in No. 9 cannot exhibit sufficient ability against electrostatic (electrostatic) destruction of IC highly integrated parts and the like. This is because only the outermost layer is the semiconductive layer, and the opposite surface, that is, the layer contacting the embossed tape (carrier tape) is the adhesive layer.
In the seal tape having such a structure, the static electricity that tends to be charged to the outermost layer is effectively discharged to be in an uncharged state, or the electric force lines (radial electric force lines) of the entire taping packaging material are embossed tape. Side toward the semi-conductive layer side so that when the seal tape is peeled off
It is possible to obtain the advantage that chips (such as chips) do not adhere to the cover tape and are not taken out (lost) to the outside. However, there is a problem in that the surface potential remains at the interface between the adhesive layer and the embossed tape, and the ability of self-discharging the peeling charge at the time of peeling at the interface.

[0009]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The inventors of the present invention have made extensive studies to solve the above-mentioned problems of the prior art.
As a result, in order to solve the above-mentioned conventional technique, a technique of providing an antistatic layer on both surfaces of a base film that constitutes the sealing tape proposed by the present inventors (Japanese Patent Application No. 1-3271).
22) has been found to be effective.

That is, the present inventors have found that when a conductive layer made of a thin film of tetracyanoquinodimethane complex and a binder resin is further provided on the adhesive layer of the cover tape which is in contact with the embossed tape, the embossed tape is formed. It was found that a cover tape having no problem in adhesion to and having an excellent antistatic property against peeling can be obtained, and the present invention has been completed.

[0011]

The present invention will be summarized as follows.
The present invention provides a taping packaging material comprising a seal tape (1) for a small electronic component and an embossed tape (2), wherein the seal tape (1) is (a) a base film layer (11), (b).
A heat-fusible sealant layer formed on the embossed tape side surface of the base film layer (12), (c) consisting of a tetracyanoquinodimethane complex and a binder resin formed on the surface of the heat-fusible sealant layer. A conductive innermost layer (13), and (d) a conductive outermost layer (14) composed of a tetracyanoquinodimethane complex and a binder resin formed on the other surface of the base film layer. The present invention relates to a taping packaging material characterized by being present.
Hereinafter, the technical configuration of the present invention will be described in detail with reference to the drawings.

First, before describing the sealing tape constituting the taping packaging material of the present invention, an overall outline of the taping packaging material will be described with reference to the drawings. As we all know,
The taping wrapping material is as shown in FIGS. FIG. 2 is a plan view of the taping packaging material (A), and FIG. 3 is a sectional view taken along line XX of FIG. IC, LS
Small electronic parts such as I (D) are recesses for device mounting (B)
Is stored in. The stored state is shown in FIG. That is, the device is mounted in the recess provided in the embossed tape (2) and sealed by the seal tape (1). In Fig. 2, the feed hole (C) is used to automatically attach the device (D) to this type of taping packaging material (A), or to automatically remove the device (D) from the taping packaging material (A). When mounting, taping packaging material (A)
To guide you.

Next, the structure of the seal tape (1) of the present invention is shown in FIG. As shown in FIG. 1, the seal tape (1) of the present invention comprises a heat-sealable sealant layer (12) on the side of an embossed tape centering on a base film layer (11), and further the heat-sealable sealant layer. A conductive innermost layer (13) using a tetracyanoquinodimethane complex is formed on (12), while on the other surface of the base film layer (11) (surface opposite to the embossed tape side). It is configured so as to form a conductive outermost layer (14) using a tetracyanoquinodimethane complex. Hereinafter, each layer will be described.

The base film layer (11) is preferably composed of a biaxially stretched film used for this type of application, for example, polyethylene terephthalate (PE).
T) film, polyamide film, polyolefin (eg polypropylene) film, etc.
The thickness of these films depends on the function as a base film (holding force of stored items, strength against external force, etc.).
Those having a thickness of ˜25 μ are preferable.

The heat-fusible sealant layer (12) may be composed of a usual hot melt type adhesive. For example, the sealant layer may be formed using a hot-melt adhesive of ethylene-vinyl acetate copolymer. The thickness of the heat-sealing sealant layer (12) is preferably 35 to 55 μm in order to provide a sufficient heat-sealing property including the primer layer (15) described later.

The conductive innermost layer (13) may be composed of a tetracyanoquinodimethane complex known as a conductivity-imparting substance and a binder resin. The tetracyanoquinodimethane complex is a generic term for complexes formed from 7,7,8,8-tetracyanoquinodimethane electron acceptor (electron acceptor) and electron donor substance (electron donor). It is easily available.
The tetracyanoquinodimethane complex forms a stable radical salt in the molecule when electrons are supplied by an electron donor substance (electron donor), and this plays a major role in imparting conductivity. .. Since the tetracyanoquinodimethane complex is a solid, it is dissolved with a binder resin in a desired solvent to prepare a coating liquid, which is coated on the heat-fusible sealant layer (12) to form the innermost layer. Form (13). In dissolving the tetracyanoquinodimethane complex, although there are restrictions on good solvents, for example, tetracyanoquinodimethane complex (manufactured by Nippon Carlit Co., Ltd., COS) 1 wt%, Acridic A-811 (Dainippon Ink and Chemicals Incorporated) Co., Ltd., isocyanate-curable acrylic resin binder) 1 wt%, Vernock DN-980 (Dainippon Ink and Chemicals, Inc., isocyanate cross-linking agent) 0.5 wt%, DMF (N, N-dimethylformamide, solvent) 40 wt%, Butyl acetate (solvent) 57.
The innermost layer (13) may be formed by preparing a coating liquid containing 5 wt%. In the present invention, since the innermost layer (13) is formed on the heat-sealing sealant layer (12), the thickness of the innermost layer (13) is sufficient so as not to impair the heat sealability of the sealant layer (12). It needs to be thin. The present inventors have found that when the innermost layer (13) is a sufficiently thin film layer, the heat sealability is not impaired. Further, in this respect, since the tetracyanoquinodimethane complex is very expensive, it gives an economic advantage to the present invention. The thickness of the innermost layer (13) is
It may be controlled to 0.01 to 0.5 μ.

The conductive outermost layer (14) is formed by using the same coating agent as the innermost layer (13). The thickness of the outermost layer (14) is the same as that of the innermost layer (13), or may be increased to some extent, but from the economical viewpoint, it is 0.05 to 0.5.
μ is preferred.

In the present invention, a primer layer (15) may be formed at the interface between the base film layer (11) and the heat-sealing sealant layer (12) so as not to separate when the seal tape (1) is peeled off. Needless to say. Alternatively,
It goes without saying that the surface of the base film such as PET may be subjected to activation treatment by a usual method. As this type of primer, for example, a polyethylene (PE) -based primer or the like is used, and the thickness of the primer layer (15) is usually about 5 μm.

The seal tape (1) of the present invention has the above-mentioned layer structure. Next, the following samples were prepared and evaluated for the performance of the seal tape (1) having the above-mentioned layer structure. (1) A seal tape having a two-layer structure in which a heat-sealing sealant layer (thickness 50 μm) is provided on a biaxially stretched PET layer (thickness 16 μm). The heat-sealing sealant layer was composed of an EVA-based (ethylene-vinyl acetate copolymer-based) hot-melt adhesive (EVA Tex 81 manufactured by Denki Kagaku Kogyo Co., Ltd.). (2) A seal tape having a three-layer structure in which the innermost layer (thickness: 0.05 μ) is provided on the heat-sealing sealant layer of the above (1) by a coating solution using a tetracyanoquinodimethane complex. The coating liquid used was that described for the conductive innermost layer (13). (3) A seal tape having a four-layer structure in which the outermost layer (thickness: 0.05 μ) is further provided on the other surface of the PET layer by a coating liquid using a tetracyanoquinodimethane complex on the surface of the above (2). The surface resistance of each of the three samples was measured using a surface resistance measuring instrument STACK TR-3 type manufactured by Tokyo Electronics Co., Ltd.
It was measured under the conditions of ° C and 65% RH. As a result, sample (1)
Those of 10 ¹² to 10 ¹³ Omega, the 10 ⁷ to that of the sample (2)
Sample (3) (invention product) of 10 ⁸ Ω surely showed a surface resistance value of 10 ⁶ Ω or less. And sample (3) (invention product)
In addition to the effect of the surface resistance value compared to the sample (2), the surface potential does not remain at the interface between the seal tape and the embossed tape, and when the seal tape is peeled off, Since the peeling electrification generated at the interface of (1) is completely self-discharged, highly integrated IC chips and the like housed in the embossed tape can be reliably prevented from electrostatic (charging) destruction. Further, as an additional effect, the heat resistance of the heat-sealing sealant layer (composed of EVA hot-melt adhesive in the above example) is the conductive innermost layer (composed of acrylic resin in the above example). There is an advantage that it is improved by. This is clear from the glass transition points of both.

[0020]

According to the present invention, in a taping packaging material composed of a seal tape and an embossed tape, the seal tape has a special four-layer structure. In particular, a heat-sealing sealant layer is formed on the side of the base film layer that comes into contact with the embossed tape, and a conductive layer using a thin film tetracyanoquinodimethane complex on both surfaces (outermost surface, innermost surface) of this product. Is formed. As a result, the surface potential that tends to remain at the interface between the seal tape and the embossed tape and the peeling charge during peeling can be surely self-discharged without impairing the sealing characteristics of the heat-sealing sealant layer. Therefore, the taping packaging material of the present invention can protect expensive and precise small electronic components from electrostatic breakdown for a long period of time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a sealing tape in a taping packaging material of the present invention.

FIG. 2 is a diagram showing an outline of a taping packaging material.

3 is a sectional view taken along line XX of FIG.

[Explanation of symbols] A ………… Taping packaging material B ………… Concave for device mounting C ………… Round hole for feeding D ………… Device 1 ………… Seal tape 2 ………… Embossing tape

Claims (6)

[Claims] 1. A taping packaging material comprising a seal tape (1) for a small electronic component and an embossed tape (2), wherein the seal tape (1) comprises (a) a base film layer (11) and (b) Heat-fusible sealant layer (12) formed on the surface of the base film layer on the embossed tape side, (c) Conductivity composed of a tetracyanoquinodimethane complex and a binder resin formed on the surface of the heat-fusible sealant layer. Innermost layer (13), and (d) a conductive film outermost layer (14) composed of a tetracyanoquinodimethane complex and a binder resin formed on the other surface of the base film layer. A taping wrapping material characterized in that. 2. The taping packaging material according to claim 1, wherein a primer layer (15) is provided between the base film layer (11) and the heat-fusible sealant layer (12). 3. The taping packaging material according to claim 1, wherein the base film layer (11) is a biaxially stretched polyethylene terephthalate film. 4. The heat-fusible sealant layer (12) is ethylene-based.
The taping packaging material according to claim 1, which is a vinyl acetate copolymer resin. 5. A conductive innermost layer (13) and a conductive outermost layer (14)
The taping packaging material according to claim 1, wherein the taping packaging material is formed using a coating agent composed of a tetracyanoquinodimethane complex, an isocyanate-curable acrylic resin, an isocyanate-based curing agent, and a solvent. 6. The taping packaging material according to claim 2, wherein the primer layer (15) is polyethylene.