JP2002193323A - Sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet that prevents damage to an electronic part, which is caused by static electricity, and to provide an electronic-part packaging container. SOLUTION: The sheet comprises a conductive layer having a surface resistivity of 104 to 1010 Ω/cm2, and a surface layer having a surface resistivity of 109 to 1014 Ω/cm2, which is provided on one or both sides of the conductive layer. The surface resistivity of the surface layer is higher than that of the conductive layer. The electronic-part packaging container uses the sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sheet and a packaging container for electronic parts. They can be used for packaging electronic components, and are particularly suitable for packaging electronic components, such as ICs, which are easily damaged by static electricity.

[0002]

2. Description of the Related Art Electronic component packaging containers are used for transporting and storing electronic components and have a surface resistivity of 10 ⁴ to 10 ⁸ Ω / cm.
^{In the second} type, the generated static electricity is easily released by grounding, thereby preventing the electrostatic breakdown of the electronic components. However, when the wiring inside the electronic component is miniaturized due to the high integration of the electronic component, 1
0 ⁴ ~10 ⁸ Ω / cm by induction from the electronic component friction and other charging of the electronic component and the container be a packaging container having a surface resistivity of ² to electronic component packaging container of static electricity generated in the electronic component In some cases, the electronic component is destroyed by the discharge of the electric current. The destruction of an electronic component due to static electricity is caused by an instantaneous temperature rise inside the electronic component due to discharge from the electronic component to the surface of the electronic component packaging container in a very short time.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet for preventing an electronic component from being damaged by static electricity and an electronic component packaging container.

[0004]

According to the present invention, the surface resistivity is 1 unit.
0 ⁴ ~10 ¹⁰ Ω / cm ² of the conductive layer has its both sides or one side 10 ⁹ ~10 ¹⁴ Ω / cm ² of the surface layer, use sheet and it is higher than the surface resistivity conductive layer of the surface layer Electronic component packaging container. The sheet and the electronic component packaging container of the present invention break the electronic component when the electronic component is charged with static electricity due to friction or induction from other charged materials by setting the conductive layer and the surface layer to predetermined surface resistivity. It is considered that the electric component is gradually discharged from the electronic component having the current value to the surface of the electronic component packaging container at one time. In other words, a high-resistance surface layer is stacked on a low-resistance conductive layer to remove static electricity from a charged electronic component over a long period of time with a minute current.
In addition, it is considered that it has a stable antistatic property due to having a low-resistance conductive layer.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION A sheet has a conductive layer and a surface layer. It is preferable that the conductive layer and the surface layer are directly laminated. The specific configuration is, for example, a surface layer / conductive layer,
Surface layer / conductive layer / substrate layer, surface layer / conductive layer / substrate layer with additional base layer, surface layer / conductive layer / substrate layer / conductive layer /
There is a surface layer and the like, but the present invention is not limited to these configuration examples, and it is sufficient if the device has a conductive layer and a surface layer.

The surface layer is on one or both sides of the conductive layer and has a surface resistivity of 10 ⁹ -10 ¹⁴ Ω / cm ² and must be higher than the conductive layer. The surface layer can be obtained, for example, by applying an antistatic agent to the surface of the conductive layer. In this case, as the antistatic agent, a silicon compound antistatic agent, a surfactant such as a group of compounds having a sulfonic acid group, a vinyl copolymer containing a hydrophilic and ionic group or a polyetheramide copolymer. Such polymeric antistatic agents can be used. In addition, a conductive resin such as polyaniline, polypyrrole, polythiophene, polyacrylonitrile, polyperinaphthalene, or polyacetylene can be used as the surface layer. It is also possible to use a thermoplastic resin to which a conductive filler such as carbon black, metal oxide, or metal fine powder is added as the surface layer. In this case, the thermoplastic resin constituting the surface layer is not particularly limited. For example, a general polystyrene resin (GPPS) or a high-impact polystyrene resin (HIPS) and a polystyrene resin containing a mixture thereof as a main component, ethylene and propylene Polyolefin resin mainly composed of a homopolymer or a copolymer mainly composed of ethylene or propylene, a polycarbonate resin mainly composed of polycarbonate, and a copolymer mainly composed of three components of acrylonitrile-butadiene-styrene. AB as the main component
S-based resin, acrylic resin based on polyacrylic acid ester such as polyacrylic acid and polymethyl acrylate, polyamide-based resin based on polyamide such as PET, polyester-based resin based on polyester, polyurethane It is possible to use a polyurethane-based resin containing as a main component and these alloy-based resins.
The thickness of the surface layer is not particularly limited, but is preferably 0.1
２０20 μm.

The conductive layer has a surface resistivity of 10 ⁴ to 10 ¹⁰
Must be in the range Ω / cm ² . The thickness is not particularly limited, but is preferably 2 to 8 times the thickness of the entire sheet.
The range is 0%. For the conductive layer, a thermoplastic resin can be preferably used. For example, a polystyrene resin having GPPS or HIPS and a mixture thereof as a main component, a homopolymer of ethylene and propylene, a copolymer mainly containing ethylene or propylene, or the like can be used. Polyolefin-based resin as a main component, polycarbonate-based resin as a main component of polycarbonate, ABS-based resin as a main component as a copolymer mainly composed of three components of acrylonitrile-butadiene-styrene, polyacrylic acid and polymethyl acrylate, etc. Acrylic resin mainly composed of polyacrylate, polyamide resin mainly composed of polyamide such as PET, polyester resin mainly composed of polyester, polyurethane resin mainly composed of polyurethane, and alloys thereof. system The use of fat is possible. In order to impart conductivity to these thermoplastic resins,
Conductive fillers such as carbon fiber, metal fiber, metal powder, and carbon black can be used, but mechanical properties such as mechanical strength and impact strength, and secondary moldability such as vacuum forming, pressure forming, hot plate forming, etc. In order to obtain carbon black, it is particularly preferable to use carbon black. Furnace black, channel black, acetylene black and the like can be used as carbon black. The amount of carbon black added is
Preferably, 5 parts per 100 parts by weight of the thermoplastic resin.
５０50 parts by weight. If the amount of carbon is less than 5 parts by weight, the conductivity is insufficient and the surface resistance value is 1 × 10 ¹⁰ Ω /
It is difficult to make it smaller than cm ² . On the other hand, if it exceeds 50 parts by weight, the mechanical properties and the secondary formability deteriorate.

It is preferable to use a thermoplastic resin for the base material layer. For example, a polystyrene resin mainly composed of GPPS or HIPS and a mixture thereof, a homopolymer of ethylene and propylene, and a copolymer mainly composed of ethylene or propylene. A having a main component of a polyolefin-based resin whose main component is a copolymer, a polycarbonate-based resin whose main component is polycarbonate, and a copolymer mainly containing three components of acrylonitrile-butadiene-styrene.
BS-based resin, acrylic resin based on polyacrylate such as polyacrylic acid and polymethyl acrylate, polyamide-based resin based on polyamide such as PET, polyester-based resin based on polyester, polyurethane Polyurethane-based resins containing these as main components and alloy resins thereof can be used.

The method for producing the sheet is not particularly limited. For example, a blend of a thermoplastic resin and a conductive filler, an antistatic agent or a conductive resin to be a surface layer and a conductive layer is respectively used in a twin-screw extruder, a continuous kneader or the like. Kneading with various kneaders into pellets, then using a plurality of extruders, supplying the base layer and the conductive layer, the resin of the surface layer to each, and using a multilayer such as a feed block method or a multi-manifold method It is possible to produce laminated sheets by coextrusion. Also, a method of sequentially coating and laminating a conductive layer and a surface layer on a base layer formed using an extruder, or coating and laminating a surface layer on a sheet of a conductive layer formed using an extruder. The production of sheets by the method is possible. The overall thickness of the sheet is
0.1 to 5.0 mm is preferred. If the thickness is less than 0.1 mm, the strength as a packaging container is poor, and the thickness is 5.0 mm.
If the ratio exceeds 2, the thickness deviation at the time of the secondary molding becomes large, and the molding becomes difficult.

The sheet can be suitably used for an electronic component packaging container. The electronic component packaging container is a container for electronic components such as an IC, a resistor, a capacitor, an inductor, a transistor, and a diode. Vacuum forming, pressure forming,
It is possible to manufacture an electronic component packaging container in a packaging form such as a vacuum molding tray, a magazine tube, a carrier tape (embossed carrier tape) by hot plate molding.

The surface resistivity is a resistance per unit surface area and is specified in JIS K6911.

[0012]

The present invention will be described in more detail with reference to the following examples. HIPS (HI-E4, Toyo Styrene) 10
Acetylene black (Denka black granular, Denki Kagaku Kogyo) was weighed at a ratio of 24 parts by weight with respect to 0 parts by weight, uniformly mixed using a high-speed kneader, and kneaded using a φ45 mm vented twin-screw extruder. A resin composition constituting a conductive layer was obtained by pelletizing by a strand cut method. A
A BS resin (GR-2000, Denki Kagaku Kogyo) is used as a base material layer, and a conductive layer having a total thickness of 0.3 mm is laminated by a feed block method using a φ65 mm extruder (L / D = 28) and a T die. A three-layer sheet of layer / base layer / conductive layer was obtained. The surface resistivity of this three-layer sheet is 1.5 × 10 ⁶ Ω /
cm ² . On one surface of this sheet, a soluble conductive resin (medium water / alcohol) containing poly (3,4-ethylenedioxythiophene) as a main component is applied in a thickness of 4 μm using a gravure coater as a surface layer. A four-layer sheet of / conductive layer / base layer / conductive layer was obtained. The surface resistivity of this surface layer was 7.4 × 10 ¹⁰ Ω / cm 2. A carrier tape is prepared by a vacuum drum molding machine so that the surface of the sheet is in contact with the surface layer, that is, the IC, and the pocket is filled with the IC as a content, and the pocket is attached to a vibration tester and the amplitude is 50 mm and the frequency is 450 rpm for 1 hour After vibrating,
After standing for 24 hours, the state of breakage of the IC due to static electricity was confirmed. As a result of this evaluation, IC destruction was not confirmed at all in 100 samples.

The sheet and the electronic component packaging container of the present invention have the effect of preventing the electronic components from being destroyed by static electricity.

Continued on front page F term (reference) 3E067 AA11 AB41 BA10A BA25A BB14A BB22A BB25A CA21 EE32 GD10 3E096 BA08 EA11X FA07 GA01

Claims (4)

[Claims] 1. A conductive layer having a surface resistivity of 10 ⁴ to 10 ¹⁰ Ω / cm ² , and 10 ⁹ to 10 ¹⁴ Ω / cm ² on both sides or one side thereof.
A sheet having a surface layer having a higher surface resistivity than the conductive layer. 2. The sheet according to claim 1, further comprising a base material layer. 3. An electronic component packaging container using the sheet according to claim 1. 4. An embossed carrier tape using the sheet according to claim 1.