JP2001315265A - Conductive composite plastic sheet and container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive composite plastic sheet for remarkably reducing a contamination of an IC or the like caused by a release of a carbon black or the like due to a wear when contacted with the IC or the like by incorporating a resin obtained by adding a hydrogen to a styrene-diene block copolymer in a conductive resin composition and a conductive plastic container made by molding the sheet. SOLUTION: The conductive composite plastic sheet is obtained by laminating the conductive resin composition on both surfaces of a sheet base material made of a thermoplastic resin. In this case, the conductive resin composition contains (B) a carbon black of 5 to 50 pts.wt. to (A) a polyphenylene ether resin of 100 pts.wt., and a resin of 1 to 30 pts.wt. in which a hydrogen is added to (C) the styrene-diene block copolymer to (B) the carbon black of 100 pts.wt. of total amount in such a manner that a surface specific resistance value of the sheet laminated with the resin composition is 102 to 1010 Ω. The conductive plastic container is obtained by molding the composite plastic sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive composite plastic sheet suitable for semiconductor packaging, in which contamination of an IC or the like caused by detachment of carbon black or the like due to abrasion at the time of contact with the IC or the like is remarkably reduced. The present invention relates to a conductive plastic container formed by molding the sheet.

[0002]

2. Description of the Related Art Injection trays, vacuum forming trays, magazines, embossed carrier tapes, and the like have conventionally been used as packaging forms for ICs and electronic components using ICs. (1) a method of applying an antistatic agent to the surface of a packaging container, (2) a method of applying a conductive paint,
(3) A method of dispersing an antistatic agent, (4) A method of dispersing a conductive filler, and the like have been implemented.

[0003] However, the method (1) shows a sufficient antistatic effect immediately after coating, but the method (1),
The antistatic agent is likely to be detached due to outflow due to moisture and abrasion, and stable performance cannot be obtained. The surface resistivity is also 1
0 is unsuitable for ⁹ to 10 ¹² Omega about a and packaging of IC that requires strict antistatic effect. The method (2) has the drawbacks that the coating tends to be non-uniform at the time of manufacture, and the anti-static effect is lost due to peeling off due to abrasion, thereby destroying the IC and contaminating the lead portion of the IC. (3)
In the method (1), it is necessary to add a large amount of an antistatic agent, so that the physical properties of the resin are reduced, and the surface specific resistance value is greatly affected by humidity, and stable performance cannot be obtained. As the conductive filler in the method (4), (a) metal fine powder,
(B) carbon fiber, (c) carbon black and the like. Among them, (a) fine metal powder and (b) carbon fiber can obtain sufficient conductivity by adding a small amount, but the moldability is remarkably deteriorated, it is difficult to disperse uniformly, and the resin component is present on the surface of the molded product. Only a skin layer is easily formed, and it is difficult to obtain a stable surface specific resistance value.

On the other hand, (c) carbon black is
It is generally used because it can be uniformly dispersed by examining the kneading conditions, etc., and it is easy to obtain a stable surface specific resistance value. And a phenomenon that the moldability decreases.

Conventionally, as resins for dispersing carbon black, polyvinyl chloride resins, polypropylene resins, polyethylene terephthalate resins for general use,
Polystyrene resin and ABS resin, 100 ℃
Polyphenylene ether resin for heat resistance above,
Polycarbonate resin and the like are used. Among these resins, polystyrene resins are used for general purposes, and polyphenylene ether resins are used for heat resistance. It is also excellent in cost. Further, as a method for improving the moldability and mechanical strength of a sheet obtained from these conductive resins, and further improving the mechanical strength of a packaging container obtained by molding the sheet, JP-A-57-205145 and JP-A-62-205 18261 and the like have been proposed. However, molded articles of the composition obtained by adding a large amount of carbon black to these resins have a disadvantage that carbon black is easily detached from the surface of the molded article due to abrasion.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks and provides a sheet substrate made of at least one kind of thermoplastic resin selected from polyphenylene ether resin, polystyrene resin and ABS resin. A sheet in which a conductive resin composition comprising at least one kind of thermoplastic resin selected from a polyphenylene ether-based resin, a polystyrene-based resin or an ABS-based resin and carbon black is laminated on both surfaces of the conductive resin composition; -A conductive composite plastic sheet containing hydrogenated resin in a diene block copolymer to significantly reduce contamination of ICs and the like due to detachment of carbon black and the like due to abrasion at the time of contact with the ICs and the like. And a conductive plastic container formed by molding the sheet. Is shall.

[0007]

That is, the first aspect of the present invention is as follows.
The invention of (1) relates to a sheet substrate made of at least one kind of thermoplastic resin selected from polyphenylene ether-based resin, polystyrene-based resin and ABS-based resin,
Conductive resin comprising at least one kind of thermoplastic resin selected from polyphenylene ether-based resin, polystyrene-based resin or ABS-based resin, (B) carbon black, and (C) styrene-diene block copolymer hydrogenated resin In the sheet laminated with the composition, (A) the conductive resin composition contains (B) 5 to 50 parts by weight of carbon black with respect to 100 parts by weight of (A) the thermoplastic resin, and (C) a styrene-diene block copolymer containing 1 to 30 parts by weight of a hydrogenated resin with respect to 100 parts by weight of the total amount of the plastic resin and (B) carbon black; It is a conductive composite plastic sheet having a surface specific resistance value of 10 ² to 10 ¹⁰ Ω of a sheet on which the composition is laminated. According to a second aspect of the present invention,
A conductive plastic container obtained by molding the conductive composite plastic sheet of the first invention by air pressure molding, vacuum molding, hot plate molding, or the like.

Hereinafter, the present invention will be described in more detail. In the present invention, at least one type of thermoplastic resin selected from a polyphenylene ether-based resin, a polystyrene-based resin, or an ABS-based resin is used for the base sheet and the conductive resin composition, and the polyphenylene ether-based resin is Polyphenylene ether resin and a resin containing a polystyrene resin as a main component, the content of the polyphenylene ether resin in the total amount of 100 parts by weight of the polyphenylene ether resin and the polystyrene resin is preferably 28 to 86 parts by weight, and less than 28 parts by weight. In such a case, sufficient mechanical properties as a polyphenylene ether-based resin cannot be obtained, and if it exceeds 86 parts by weight, the flowability is reduced and molding processing becomes difficult. The polyphenylene ether resin is described in US Pat.
The homopolymer or copolymer described in No. 3435 is shown.

The polystyrene resin used in the present invention refers to a resin mainly composed of a general polystyrene resin or impact-resistant polystyrene resin and a mixture thereof. ABS
The term "based resin" means a resin mainly composed of a copolymer mainly composed of three components of acrylonitrile-butadiene-styrene.

The carbon black (B) contained in the conductive resin composition of the present invention is furnace black, channel black, acetylene black or the like, and preferably has a large specific surface area and a small amount of addition to the resin. Is obtained. For example, C. F. (S
upper Conductive Furnace),
E. FIG. C. F. (Electric Conductiv
e Furnace), Ketjen Black (trade name, manufactured by Lion-AKZO) and acetylene black. The amount of carbon black added is such that the surface specific resistance value can be set to 10 ² to 10 ¹⁰ Ω in a state of being laminated on the base sheet, and (A) the thermoplastic resin 100
(B) 5 to 50 parts by weight of carbon black is preferred based on parts by weight. If the added amount is less than 5 parts by weight, sufficient conductivity cannot be obtained and the surface resistivity increases, and if it exceeds 50 parts by weight, the uniform dispersibility with the resin is deteriorated, the moldability is significantly reduced, Characteristic values such as strength are reduced. On the other hand, if the surface specific resistance value exceeds 10 ¹⁰ Ω, a sufficient antistatic effect cannot be obtained. If the surface specific resistance value is less than 10 ² Ω, the power generation capability is so good that the IC may be broken.

The resin obtained by hydrogenating the styrene-diene block copolymer (C) used in the present invention is obtained by hydrogenating a styrene-diene block copolymer. (C) A resin obtained by hydrogenating a styrene-diene block copolymer has a melt flow index (JIS-K
Is less than 0.1 g / 10 min under the conditions of 200 ° C. and a load of 5 kg. If the value is less than this value, polyphenylene ether resin, polystyrene resin,
Kneading with an ABS resin becomes difficult, and a good composition cannot be obtained. As the diene of the styrene-diene block copolymer before hydrogenation, butadiene or isoprene is preferred. The styrene content in the hydrogenated resin of the styrene-diene block copolymer is 10 to 80.
%, Preferably 10 to 50% by weight. If the styrene content in the hydrogenated resin of the styrene-diene block copolymer is less than 10% by weight, the dispersibility in polyphenylene ether-based resin, polystyrene-based resin, and ABS-based resin is reduced, and the mechanical strength is reduced. If it exceeds 80% by weight, the effect of improving the removal of carbon black and the like cannot be sufficiently obtained.

(C) The amount of the hydrogenated resin added to the styrene-diene block copolymer is preferably 1 to 30 parts by weight, particularly preferably 3 to 30 parts by weight, per 100 parts by weight of the total amount of the thermoplastic resin and carbon black. ２５25 parts by weight.
If the amount is less than 1 part by weight, the effect is insufficient.
If the amount exceeds 0 parts by weight, the dispersion in the polyphenylene ether-based resin, polystyrene-based resin, and ABS-based resin becomes non-uniform, resulting in a decrease in tensile modulus and a decrease in breaking point strength.
The inherent properties of the BS resin are impaired.

The conductive resin composition of the present invention is used in such a manner that a sheet laminated with the conductive resin composition has a surface specific resistance of 10 ² to 10 ¹⁰ Ω in order to maintain sufficient moldability. When filled with black, the melt flow index (measured according to JIS-K-7210) is 230 when the polyphenylene ether resin is used.
0 ° C., a load of 10 kg, a polystyrene resin at 200 ° C., a load of 5 kg, and an ABS resin at a temperature of 220 ° C., a load of 10 kg.
It is preferably at least 1 g / 10 minutes.

Further, the thermoplastic resin and the conductive resin composition of the sheet substrate may contain a lubricant, a plasticizer, a processing aid, if necessary, in order to improve the flow characteristics of the composition and the mechanical properties of the molded product. Various additives such as a reinforcing agent (resin modifier) and other resin components can be added.

In order to manufacture the conductive composite plastic sheet of the present invention, first, all or a part of the raw material of the conductive resin composition is kneaded and pelletized by using a known method such as a Banbury mixer or an extruder. The obtained conductive resin composition is formed into a sheet by a known method such as an extruder together with a thermoplastic resin serving as a base sheet.

At the time of kneading the conductive resin composition, it is possible to knead the raw materials at one time.
It is also possible to knead the styrene-based resin and carbon black, and the styrene-based resin and the styrene-diene block copolymer separately by kneading the hydrogenated resin, and knead the kneaded material in a batch at the end. It is possible. Furthermore, when the pellets obtained by separately kneading are formed into a sheet by an extruder, they are kneaded at the same time.
It is also possible to knead a resin other than the hydrogenated resin to the diene block copolymer in advance and to add it when forming a sheet with an extruder.

As a method of laminating the conductive resin composition on the base sheet, each of them is separately formed into a sheet or a film by an extruder and then stepwise formed by a heat lamination method, a dry lamination method, an extrusion lamination method or the like. It is also possible to obtain sheets which are collectively laminated by a multilayer coextrusion method using a feed block, a multi-manifold die or the like.

The total thickness of the sheet of the present invention is 0.1 to
It is 3.0 mm, and the conductive resin composition layer needs to be laminated on both sides of the base sheet. The ratio of the conductive resin composition to the entire thickness is preferably 2% or more on each side, and preferably 80% or less on both sides.
If the total thickness is less than 0.1 mm, the strength as a packaging container obtained by molding the sheet is insufficient, and if it exceeds 3.0 mm, molding such as air pressure molding, vacuum molding, and hot plate molding becomes difficult. Also, the conductive resin composition layer is only on one side of the sheet, or the ratio of the conductive resin composition layer to the total thickness is 2% on one side.
If it is less than 80%, the surface resistivity of the packaging container obtained by molding the sheet becomes extremely high, so that a sufficient antistatic effect cannot be obtained. Will drop.

The conductive composite plastic sheet of the present invention is suitable for semiconductor packaging, and is further obtained by forming the sheet by a known sheet forming method such as pressure forming, vacuum forming, hot plate forming and the like. Plastic containers
Used as a semiconductor packaging container. The plastic container specifically refers to a vacuum-formed tray for packaging ICs, a magazine, an embossed carrier tape, an electronic component using ICs, a vacuum-formed tray for packaging electronic devices, and the like.

[0020]

The present invention will be described in more detail with reference to the following examples. Examples 1 to 7 The raw materials shown in Table 1 were used, weighed at the raw material composition ratios shown in Table 2, and uniformly mixed by a high-speed mixer.
The mixture was kneaded using a mm vent type twin screw extruder, and pelletized by a strand cut method to obtain a conductive resin composition. Next, the combination of the base sheet and the conductive resin composition layer shown in Table 4 was carried out at a ratio of the base sheet to the total thickness. Each conductive resin composition is extruded with a φ65 mm extruder (L / D = 28) so that both sides of the base sheet have substantially the same thickness.
The sheets were laminated by a feed block method using a φ40 mm extruder (L / D = 26) and a T die having a width of 500 mm to obtain a sheet having a total thickness of 300 μm. Further, the obtained composite sheet is vacuum formed and QFP 14 mm × 20 mm / 64p
The obtained vacuum molded tray for IC packaging and the embossed carrier tape were obtained. Tables 6 and 7 show the evaluation results. In each of the examples, the carbon black did not fall off and was good.

Comparative Examples 1 to 4 In the same manner as in the examples, the raw materials shown in Table 1 were used, each was weighed at the raw material composition ratio shown in Table 3, and uniformly mixed by a high-speed mixer. The mixture was kneaded using a twin-screw extruder and pelletized by a strand cut method to obtain a conductive resin composition. Next, with the combination with the base sheet shown in Table 5 and the ratio of the base sheet to the total thickness, a sheet having a total thickness of 300 μm was obtained in the same manner as in the example. Further, the obtained sheet was vacuum-formed to obtain the same vacuum-forming tray for IC packaging and embossed carrier tape as in the examples. Tables 6 and 7 show the evaluation results.

Each evaluation was performed by the following method. (1) Surface specific resistance The distance between the electrodes was 10 mm using a Lorester surface resistance meter (manufactured by Mitsubishi Yuka), and any 10 points on the surface of the sheet sample were measured. For the vacuum forming tray and embossed carrier tape, The central 10 points on the inner bottom surface of the pocket were measured, and the logarithmic average value of each was taken as the surface resistivity. (2) Break Point Strength and Tensile Elasticity The No. 2 test piece was measured at a tensile speed of 10 mm / min according to JIS-K-7113 for the sheet sample.

(3) Presence / absence of carbon detachment The surface of the sheet sample is QFP 14 mm ×
A 20 mm / 64 pin IC is pressed with a load of 100 g and reciprocated 100 times with a stroke of 15 mm.
The lead part of C was observed with a microscope. For the vacuum forming tray and embossed carrier tape, the same IC is mounted in the pocket portion and the stroke is 30 mm and the speed is 40 min / min.
Vibration in the plane direction 200,000 times at a speed of 0 reciprocations.
The C lead was observed with a microscope. The evaluation was based on the presence or absence of black deposits such as carbon black on the lead portions. (4) MFI JIS for conductive resin compositions of Examples and Comparative Examples
The measurement was performed according to -K-7210.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

[Table 3]

[0027]

[Table 4]

[0028]

[Table 5]

[0029]

[Table 6]

[0030]

[Table 7]

[0031]

As described above, a polyphenylene ether-based resin, a polystyrene-based resin, or a polyphenylene ether-based resin is provided on both surfaces of a sheet substrate made of at least one thermoplastic resin selected from a polyphenylene ether-based resin, a polystyrene-based resin, and an ABS-based resin. In a sheet in which a conductive resin composition comprising at least one kind of thermoplastic resin selected from ABS resin and carbon black is laminated, the conductive resin composition is further hydrogenated to a styrene-diene block copolymer. A conductive composite plastic sheet which has significantly reduced contamination of ICs and the like due to detachment of carbon black due to abrasion at the time of contact with the ICs and the like, and a conductive material obtained by molding the sheet. It becomes possible to obtain a plastic container.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 71/12 (C08L 71/12 // (C08L 71/12 53:02) 53:02) B65D 85 / 38 S

Claims (4)

[Claims] At least one selected from a polyphenylene ether resin, a polystyrene resin and an ABS resin.
On both sides of a sheet substrate made of various types of thermoplastic resin,
In a sheet obtained by laminating a conductive resin composition comprising (A) a polyphenylene ether-based resin , (B) carbon black, and (C) a resin obtained by hydrogenating a styrene-diene block copolymer, (a) the conductive resin composition Things are (A)
(B) 5 to 50 parts by weight of carbon black with respect to 100 parts by weight of polyphenylene ether-based resin, and (A) polyphenylene ether-based resin and (B)
Resin 1 obtained by hydrogenating (C) styrene-diene block copolymer with respect to 100 parts by weight of total amount of carbon black
JIS-K-7 of a resin obtained by hydrogenating a styrene-diene block copolymer (C).
The melt flow index measured according to 210 is 2
0.1 g / 10 min or more under the conditions of 00 ° C. and a load of 5 kg, the styrene content is 10 to 80% by weight, and
(B) A conductive composite plastic sheet with less carbon falling-off, characterized in that the sheet laminated with the conductive resin composition has a surface specific resistance of 10 ² to 10 ¹⁰ Ω. 2. The total thickness is 0.1 to 3.0 mm, and the ratio of the conductive resin composition to the total thickness is 2 on each side.
%, And 80% or less for both surfaces.
4. The conductive composite plastic sheet according to item 1. 3. A conductive plastic container comprising the conductive composite plastic sheet according to claim 1. 4. A semiconductor packaging container comprising the conductive composite plastic sheet according to claim 1.