JP2006307032A - Bottom cover tape for small electronic part carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bottom cover tape which is used for small electronic part carriers, ensures adhesiveness to paper carriers, has excellent antistaticity, and prevents the tape adhesion and corrosion of small electronic parts. <P>SOLUTION: This bottom cover tape for small electronic part carriers is characterized by comprising a laminate of a support, an adhesive layer, and an anti-static layer, wherein the adhesive layer comprises (A) 90 to 50 wt.% of a polyolefin-based resin as a base polymer and (B) 10 to 50 wt.% of one of ethylene-ethyl acrylate copolymer resin, ethylene-methyl methacrylate copolymer resin, and ethylene-ethyl methacrylate copolymer resin, or a copolymer comprising their mixture, having a monomer content; and the anti-static layer comprises an alkyl dimethylethylammonium ethosulfate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a bottom cover tape for a small electronic component carrier that covers a bottom surface of a carrier tape used for a chip type electronic component carrier with a heat seal.

  Conventionally, as a method for transporting small electronic components such as IC chips and capacitors, it is called a paper carrier in which tape-like cardboard having a certain width is punched with square holes for accommodating small electronic components at regular intervals in the length direction. The bottom of the carrier tape is covered with a bottom cover tape with a heat seal to form a small electronic component storage part. Immediately after the small electronic component is stored in this part, the top surface of the paper carrier is heat sealed with a top cover tape. In general, a method in which the film is covered with, wound in a reel shape, and conveyed.

  When using small electronic components, an automatic assembly system in which the top cover tape is peeled off and the small electronic components are adsorbed by an air nozzle and mounted on a circuit board has become the mainstream.

Then, static electricity is generated by vibration of the small electronic components during transportation, so that the small electronic components adhere to the tape, adhere to the adhesive layer of the tape depending on the storage environment (temperature / humidity), and the small electronic components using the tape. There is a problem of corrosion of parts. Many proposals have been made on improvements relating to antistatic properties and adhesion suppression to the adhesive layer (see, for example, Patent Documents 1 and 2).
JP 2001-3014 A JP 2003-292033 A

  However, in particular, in recent years, static electricity has been generated due to vibrations caused by small electronic components being transported, and the antistatic performance has been insufficient due to a decrease in humidity due to changes in the storage environment. In addition to the problem that the small electronic component cannot be adsorbed to the air nozzle, the problem of corrosion of the small electronic component by the tape has also occurred.

  An object of the present invention is to provide a bottom cover tape for a small electronic component transporter that ensures adhesion to a paper carrier, has excellent antistatic properties, and prevents adhesion of small electronic components to the tape and corrosion.

  The present invention can solve the above-described problems by including the following configuration.

  (1) It is a laminate of an adhesive layer and an antistatic layer on a support, and the adhesive layer has a monomer content of (A) 90-50% by weight of a polyolefin resin as a base polymer and (B) a monomer content of 10-50% by weight. 5% by weight or more of an ethylene ethyl acrylate copolymer resin, an ethylene methyl methacrylate copolymer resin, an ethylene ethyl methacrylate copolymer resin, or a copolymer resin thereof, and the antistatic layer is alkyl. A bottom cover tape for a small electronic component carrier characterized by comprising dimethylethylammonium etosulphate.

  (2) The bottom cover tape for a small electronic component carrier according to (1) above, wherein the adhesive layer has a thickness of 10 to 50 μm.

(3) The thickness of the antistatic layer is 0.01 to 0.001 μm in terms of active ingredient, and the surface resistivity is maintained at 10 ⁸ to 10 ¹² Ω / □ even under low humidity (about 20%). The bottom cover tape for a small electronic component transport body according to the above (1) or (2).

  According to the present invention, it is composed of three layers of an adhesive layer and an antistatic layer based on a support, and the adhesive layer is (A) a polyolefin resin as a base polymer and (B) a monomer content of 5% by weight or more. Good thermal adhesiveness to paper carrier by comprising a copolymer resin that is one of ethylene ethyl acrylate copolymer resin, ethylene methyl methacrylate copolymer resin, ethylene ethyl methacrylate copolymer resin, or a mixture thereof. As the above copolymer resin does not contain an acid group that is advantageous for metal bonding, small electronic components are less likely to adhere to the adhesive layer due to changes in the storage environment, and corrosion by acid can be prevented, Since the alkyldimethylethylammonium ethoxide in the antistatic layer is halogen free, And, even for a rapid change in elevation condition in temperature, never corrode small electronic components. In addition, as the performance of alkyldimethylethylammonium ethosulphate, since the antistatic performance is not impaired even under low humidity, it is always possible to safely transport and maintain the quality of small electronic components.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to examples.

  The configuration of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing the configuration of the present invention. 1 is a bottom cover tape, 2 is a support layer, 3 is an adhesive layer, and 4 is an antistatic layer.

What constitutes the support layer 2 only needs to have a self-supporting property, and examples thereof include paper such as Japanese paper, thin paper, and mixed paper, and nonwoven fabric made of olefin resin such as polyethylene and polypropylene. 5 to 100 g / m ² , preferably 10 to 50 g / m ² . Further, a surface treatment may be applied to the adhesive layer side of the support layer 2 in order to improve anchoring properties, and a corona treatment or the like is a commonly used technique. Furthermore, an antistatic treatment, a heat retention treatment, or the like may be performed on the opposite side of the support layer 1 as necessary.

  The adhesive layer 3 is made of a thermoplastic resin, and is composed of a polyolefin resin as a base polymer and an ethylene copolymer resin. Specifically, the base polymer includes low density polyethylene, linear low density polyethylene, and metallocene catalyst linear. Any one such as low density polyethylene or a mixture thereof is used. As the ethylene copolymer resin, any one of ethylene ethyl acrylate copolymer resin, ethylene methyl methacrylate copolymer resin, ethylene ethyl methacrylate copolymer resin having a monomer content of 5% by weight or more, or a mixture thereof can be used. For ethylene resins, ethylene vinyl acetate copolymer resin, ionomer resin, ethylene acrylic acid copolymer resin, ethylene methacrylic acid copolymer resin, etc. have excellent adhesion to metals, but conversely, small electronic components may easily adhere. In addition, since there is a possibility that the metal is corroded by an acid generated by thermal decomposition or the like, it is not suitable for the present invention.

  The blending amount of the base polymer and the ethylene copolymer resin is 90 to 50% by weight of the base polymer and 10 to 50% by weight of the ethylene copolymer resin, preferably 75 to 60% by weight of the base polymer and 25 of the ethylene copolymer resin 25. The thickness of the adhesive layer 3 is about 10 to 50 μm, preferably 15 to 35 μm.

  Further, the support layer 1 side of the adhesive layer 3 may be subjected to surface treatment such as ozone treatment to improve anchoring properties, and further to the antistatic layer 4 side of the adhesive layer 3 as necessary. Surface treatment such as corona treatment may be applied.

The antistatic layer 4 uses alkyldimethylethylammonium ethosulphate. Alkyldimethylethylammonium etosulphate is a halogen-free cationic antistatic agent, but the surface resistivity is 10 ⁸ to 10 even when the thickness of the antistatic agent layer is 0.01 to 0.001 μm in terms of active ingredient. ¹² Ω / □ can be ensured, and the antistatic performance is not impaired even under low humidity (about 20%). The application method is not particularly limited, and examples thereof include a non-contact application method such as a spray process using a high-pressure nozzle and a spray process using centrifugal force, and a gravure coat process.

  Moreover, since the coating film of the antistatic layer 4 is extremely thin, the adhesive force of the adhesive layer by heat sealing to the paper carrier is not hindered.

  Next, a specific manufacturing method will be described below.

[Creation of laminated film]
A corona treatment is applied to a thin paper having a basis weight of 14 g / m ² , and 75% by weight of low density polyethylene (Sumikasen L-405 (registered trademark): Sumitomo Chemical) as a base polymer, and ethylene methyl as an ethylene copolymer resin. An adhesive layer containing 25% by weight of a methacrylate copolymer resin (ACRIFTH WH302 (registered trademark): Sumitomo Chemical) was laminated to a thickness of 20 μm by extrusion lamination. Thereafter, the adhesive layer was subjected to corona treatment, and a tape having a coating thickness of 0.005 μm was obtained by gravure coating treatment with alkyldimethylethylammonium ethosulphate as an antistatic layer.

  On the adhesive layer of the bottom cover tape obtained in the examples, 50 nickel particles having a particle diameter of about 1 mm were placed on top, and a load of about 150 g of a metal plate was applied to the adhesive layer in an environment of 80 ° C. × 90%. For 120 hours to confirm the corrosion of nickel and the number of adhesion to the adhesive layer. As a result, nickel corrosion and adhesion to the adhesive layer were not observed.

Further, when the surface resistivity was confirmed after being left in an environment of 23 ° C. × 20% for 120 hours, it showed a surface resistivity of 10 ⁹ Ω / □.

In FIG. 1, the thickness of each layer is as follows.
1: Bottom cover tape (total thickness) 40 μm
2: Support layer 20 μm (basis weight 14 g / m ² )
3: Adhesive layer 20 μm
4: Antistatic layer 0.005 μm (in terms of active ingredient)
In addition, the said Example is a mere illustration, The weight% of (A) and (B) in an adhesive layer is preferable in this range, and when it heat-seals other than this range, the low-temperature heat sealing function of an adhesive bond layer In addition, there is a problem that the function of suppressing adhesion of small electronic components may be deteriorated and cost merit is lost. Furthermore, the thickness of the support is also a necessary condition, and the thickness of the support is not constant depending on the material. The antistatic layer is also related to the size and volume of the small electronic component, but is not necessarily restricted by certain conditions. It is not a thing.

It is a schematic cross section which expands and shows a part of bottom cover tape which concerns on this invention.

Explanation of symbols

1 Bottom cover tape 2 Support layer 3 Adhesive layer 4 Antistatic layer

Claims (3)

  It is a laminate of an adhesive layer and an antistatic layer on a support, and the adhesive layer comprises (A) a polyolefin resin 90 to 50% by weight as a base polymer and (B) a monomer content 5% by weight of 10 to 50% by weight. It consists of a copolymer resin that is one of the above-mentioned ethylene ethyl acrylate copolymer resin, ethylene methyl methacrylate copolymer resin, ethylene ethyl methacrylate copolymer resin, or a mixture thereof, and the antistatic layer is alkyldimethylethyl ammonium. A bottom cover tape for a small electronic component carrier characterized by comprising ethosulfate.   The thickness of an adhesive bond layer is 10-50 micrometers, The bottom cover tape for small electronic component conveyance bodies of Claim 1 characterized by the above-mentioned. The thickness of the antistatic layer is 0.01 to 0.001 μm in terms of active ingredient, and the surface resistivity can maintain the performance of 10 ⁸ to 10 ¹² Ω / □ even at low humidity (about 20%). Item 3. The bottom cover tape for a small electronic component carrier according to Item 1 or 2.

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