JP3202553B2 - Conductive composite plastic sheet and container - Google Patents

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 a 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 conductive resin composition comprising at least one thermoplastic resin selected from a polyphenylene ether-based resin, a polystyrene-based resin or an ABS-based resin, and carbon black on both surfaces of the sheet, wherein the conductive resin composition has an olefin Containing a mixture of two or more different block copolymers produced from styrene and conjugated dienes with a base resin prevents contamination of ICs etc. caused by detachment of carbon black etc. due to abrasion at the time of contact with ICs etc. Conductive composite plastic sheet with significantly reduced and molded sheet It is an object to provide a conductive plastic containers.

[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,
Block copolymer produced from at least one thermoplastic resin selected from polyphenylene ether resin, polystyrene resin or ABS resin, (B) carbon black, (C) olefin resin and (D) styrene and conjugated diene (A) the conductive resin composition contains (B) 5 to 50 parts by weight of carbon black based on 100 parts by weight of the thermoplastic resin (A), and Based on 100 parts by weight of the total amount of the thermoplastic resin (A) and the carbon black (B), 1 to 30 parts by weight of (C) an olefin-based resin and (D) two or more different kinds produced from styrene and a conjugated diene. Of the block copolymer in a total amount of 0.2
And (2) a sheet on which the conductive resin composition is laminated has a surface specific resistance of 10 ² to 10
^This is a conductive composite plastic sheet having a resistance of ¹⁰ Ω.

[0008] The second invention of the present invention relates to a star-shaped copolymer having at least one of (D1) a styrene content of 50 to 90% by weight in two or more different block copolymers produced from (D) styrene and a conjugated diene. The conductive composite plastic sheet according to the first invention, which is a block copolymer and at least one other is (D2) a star or linear block copolymer having a styrene content of 10 to 50% by weight. A third invention of the present invention is 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. A fourth invention of the present invention is a conductive plastic container obtained by molding the conductive composite plastic sheet of the second invention by pressure forming, vacuum forming, hot plate forming or the like.

Hereinafter, the present invention will be described in more detail. In the present invention, at least one kind of thermoplastic resin selected from polyphenylene ether-based resin, polystyrene-based resin and ABS-based resin is used for the base sheet and the conductive resin composition, respectively. The polyphenylene ether-based resin refers to a resin having a polyphenylene ether resin and a polystyrene-based resin as main components, and the content of the polyphenylene ether resin in the total amount of 100 parts by weight of the polyphenylene ether resin and the polystyrene-based resin is 28 to 86 parts by weight. If the amount is less than 28 parts by weight, sufficient mechanical properties as a polyphenylene ether-based resin cannot be obtained. If the amount exceeds 86 parts by weight, the fluidity 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.

Examples of the olefin resin (C) used in the present invention include a homopolymer of ethylene and propylene, a copolymer containing ethylene or propylene as a main component, and a blend thereof. In the present invention, among these, particularly low-density polyethylene resin,
It is preferable to use a polyethylene resin represented by a high-density polyethylene resin or a linear low-density polyethylene resin. The melt flow index of the olefin resin (C) of the present invention is 190 ° C., a load of 2.16 kg (JI
(Measured according to SK-7210) is 0.1 g / 10 min or more. If the value is less than this value, kneading with a polyphenylene ether-based resin, polystyrene-based resin, or ABS resin becomes difficult, and a good composition cannot be obtained. . The addition amount of the olefin resin is preferably from 1 to 30 parts by weight, more preferably from 3 to 25 parts by weight, based on 100 parts by weight of the total of (A) the thermoplastic resin and (B) the carbon black. Addition amount is 1
If the amount is less than 30 parts by weight, the effect is insufficient. If the amount exceeds 30 parts by weight, it is difficult to uniformly disperse the resin in a polyphenylene ether-based resin, a polystyrene-based resin, or an ABS-based resin.

In the present invention, the conjugated diene of the block copolymer (D) produced from styrene and a conjugated diene is butadiene or isoprene, and more specifically, a block copolymer of styrene and butadiene, a block copolymer of styrene and isoprene, and the like. . This block copolymer is specifically described in US Pat.
No. 3 or a branched star-shaped block copolymer or, for example, (S1)-(Bu)-(S2) (S
1, S2 is a block formed of styrene, and Bu is a block formed of butadiene or isoprene.)

In the second aspect of the present invention, the conductive resin composition contains two or more different block copolymers produced from styrene and a conjugated diene.
At least one of them is a (D1) branched star-shaped block copolymer, the styrene content of which is 50 to 90% by weight, and at least one other is a (D2) branched star-shaped star block copolymer. Preferably, it is a block copolymer or a linear block copolymer having at least three blocks, and its styrene content is 10 to 50% by weight. The branched star-shaped block copolymer often contains a linear block copolymer due to the nature of its production method, but it is not necessary to remove it, and a mixture of these can be used. The block copolymer produced from styrene and the conjugated diene used in the present invention may be selectively or partially hydrogenated, and only the double bond in the block composed of butadiene or isoprene monomer is saturated. Is what is being done.

In the present invention, as a resin composition of (C) an olefin resin and (D) two or more different block copolymers produced from styrene and a conjugated diene,
It is also possible to use an alloy resin in which a block copolymer has been kneaded with a styrene resin and an olefin resin in advance.
Can be used.

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 carbon black, the melt flow index (measured in accordance with JIS-K-7210) is 230.
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 base may include a lubricant, a plasticizer, a processing aid and a reinforcing agent, if necessary, in order to improve the flow characteristics of the composition and the mechanical properties of the molded product. Various additives such as (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. When kneading the conductive resin composition, it is also possible to knead the raw materials collectively, for example, a styrene resin and carbon black,
It is also possible to knead the mixture of the styrene resin and the olefin resin, and the mixture of the styrene resin and the block copolymer separately, and to knead the kneaded material stepwise such that the kneaded material is kneaded all at once. Furthermore, it is also possible to simultaneously knead the pellets obtained by kneading separately when they are formed into a sheet by 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 film by an extruder, and then stepwise formed by a heat laminating method, a dry laminating method, an extrusion laminating 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 substrate sheet. The ratio of the thickness of the conductive resin composition to the total 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 forming a sheet is insufficient, and the thickness is 3.0.
If it exceeds mm, molding such as air pressure molding, vacuum molding and hot plate molding becomes difficult. Further, if the conductive resin composition layer is only on one side of the sheet, or if the ratio of the conductive resin composition layer to the total thickness is less than 2% on one side, the surface specific resistance value of the packaging container obtained by molding the sheet becomes extremely high, so that it is sufficient. If the static electricity preventing effect cannot be obtained, and if both surfaces exceed 80%, the properties such as the mechanical strength of the composite plastic sheet deteriorate.

The conductive composite plastic sheet of the present invention is suitable for packaging semiconductors. Further, the conductive composite plastic container obtained by a known sheet forming method such as pressure forming, vacuum forming, hot plate forming, etc. Used as a container for Specific examples of the plastic container include a vacuum forming tray for packaging an IC, a magazine, an embossed carrier tape, an electronic component using the IC, and a vacuum forming tray for packaging an electronic device.

[0021]

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, a combination of the base sheet and the conductive resin composition layer shown in Table 4 was performed at a ratio of the base sheet to the entire thickness. Each conductive resin composition was extruded into a φ65 mm extruder (L / D = 2) such that both sides of the base sheet had substantially the same thickness.
8), φ40mm extruder (L / D = 26) and 500m
The sheets were laminated by a feed block method using an m-width T die to obtain a sheet having a total thickness of 300 μm. Further, the obtained sheet is vacuum formed and QFP 14 mm × 20 mm / 64
Thus, a vacuum molded tray for IC packaging and an 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 7 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 the mixture was 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, the combination of the base sheet and the conductive resin composition layer shown in Table 5 was performed at a ratio of the base sheet to the entire thickness. As in the example, a sheet having a total thickness of 300 μm was obtained. The obtained sheet was vacuum formed to obtain the same vacuum forming tray for IC packaging and embossed carrier tape as in the examples. For Comparative Example 7, it was difficult to mold a semiconductor packaging container. 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 or absence of carbon detachment The surface of the sheet sample was 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.
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.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

[0028]

[Table 4]

[0029]

[Table 5]

[0030]

[Table 6]

[0031]

[Table 7]

[0032]

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 kind of 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 produced from an olefin resin, styrene and conjugated diene. And a conductive composite plastic sheet which contains two or more different block copolymers, thereby significantly reducing the contamination of ICs and the like caused by the desorption of carbon black due to abrasion upon contact with the ICs and the like. It is possible to obtain a conductive plastic container formed by molding It made.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI B32B 27/28 B32B 27/28 27/30 27/30 B (56) References JP-A-63-299923 (JP, A) JP-A-57-205145 (JP, A) JP-A-6-305084 (JP, A) JP-A-7-21834 (JP, A) JP-A-58-31749 (JP, A) JP-A-3-87097 ( JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 B65D 65/40 B65D 85/86-85/90 H01B 1/20-1/24 WPI / L (QUESTEL)

Claims (10)

(57) [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,
It is produced from (A) at least one kind of thermoplastic resin selected from polyphenylene ether resin, polystyrene resin or ABS resin, (B) carbon black, (C) olefin resin, and (D) styrene and conjugated diene. (A) the conductive resin composition contains (B) 5 to 50 parts by weight of carbon black with respect to (A) 100 parts by weight of the thermoplastic resin. And (A)
Total amount of thermoplastic resin and carbon black (B) 100
(C) 1 to 30 parts by weight of an olefin-based resin and (D) two or more different block copolymers produced from styrene and a conjugated diene in a total amount of 0.2 to 0.2 parts by weight.
And (2) a sheet on which the conductive resin composition is laminated has a surface specific resistance of 10 ² to 10
A conductive composite plastic sheet characterized by ¹⁰ Ω. 2. In the above (D) two or more different block copolymers produced from styrene and a conjugated diene, at least one of them comprises (D1) a styrene content of 50 to 9;
2. The conductive material according to claim 1, which is 0% by weight of a star block copolymer and at least one other is a (D2) star or linear block copolymer having a styrene content of 10 to 50% by weight. Composite plastic sheet. 3. The olefin resin is a polyethylene resin,
3. The conductive composite plastic sheet according to claim 1, which is an ethylene-ethyl acrylate copolymer resin or a blend thereof. 4. The olefin resin according to claim 1, which has a melt flow index of 190 ° C. and a load of 2.16 kg and is 0.1 g / 10 min or more as measured according to JIS-K-7210. The conductive composite plastic sheet according to claim 1. 5. The method according to claim 1, wherein the thickness is 0.1 to 3.0 mm.
The conductive composite plastic sheet according to any one of claims 1 to 4. 6. The method according to claim 1, wherein the ratio of the thickness of the conductive resin composition to the total thickness is 2% or more on each side and 80% or less on both sides. 4. The conductive composite plastic sheet according to item 1. 7. A conductive composite plastic container comprising the conductive composite plastic sheet according to any one of claims 1 to 6. 8. A semiconductor packaging container comprising the conductive composite plastic sheet according to any one of claims 1 to 6. 9. A vacuum forming tray for IC packaging.
Semiconductor packaging container. 10. The semiconductor packaging container according to claim 8, which is an embossed carrier tape for IC packaging.