JP3328090B2 - Conductive resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a conductive resin composition for IC packaging, comprising a thermoplastic resin selected from at least one of polyphenylene ether resin, polystyrene resin and ABS resin, and carbon black.
By causing the conductive resin composition to contain a polymer or copolymer having a siloxane bond in a main skeleton or a side chain, the removal of carbon black or the like due to abrasion at the time of contact with the IC or the like causes an IC. I significantly reduced the contamination of
C relates to a conductive resin composition for packaging.

[0002]

2. Description of the Related Art Injection trays, vacuum forming trays, magazines, embossed carrier tapes, and the like have conventionally been used for packaging 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 or a conductive filler or the like has been implemented. However, although the method (1) shows a sufficient antistatic effect immediately after coating, the antistatic agent is liable to flow out due to moisture and detached due to abrasion due to long-term use, and stable performance cannot be obtained. Also, the surface specific resistance is about 10 ⁹ Ω to 10 ¹² Ω, which is unsuitable for packaging ICs requiring a strict antistatic effect. (2)
The method (1) has the drawbacks that the coating tends to be non-uniform in production, and the antistatic effect is lost due to peeling off due to abrasion, the IC is destroyed, and the leads of the IC are contaminated. In the method (3), a large amount of the antistatic agent is required, so that the physical properties of the resin are deteriorated, and the surface specific resistance value is greatly affected by humidity, so that stable performance cannot be obtained.

[0003] As the conductive filler, metal fine powder,
Examples include carbon fiber and carbon black. Of these metal powders and carbon fibers, sufficient conductivity can be obtained with a small amount of addition, but the moldability is remarkably reduced, it is difficult to disperse uniformly, and the skin layer of only the resin component is formed on the surface of the molded product. And it is difficult to obtain a stable surface specific resistance value. On the other hand, carbon black is commonly used because carbon black can be uniformly dispersed by studying kneading and the like and a stable surface specific resistance value is easily obtained, but it is necessary to add a large amount of carbon black. , There is a phenomenon that the fluidity and moldability decrease.

Conventionally, resins for dispersing carbon black include 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, polyphenylene ether resin is used for heat resistance, and polystyrene resin and ABS are used for general use.
Even if a large amount of carbon black is added to the system resin, the fluidity and the moldability are not remarkably reduced, and the cost is more excellent. However, a molded article of the composition containing a large amount of carbon black has a disadvantage that carbon black is easily detached from the surface of the molded article due to abrasion.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above drawbacks and comprises a thermoplastic resin selected from at least one of polyphenylene ether resin, polystyrene resin and ABS resin, and carbon black. In the conductive resin composition for IC packaging, the conductive resin composition further contains a polymer or a copolymer having a siloxane bond in a main skeleton or a side chain, whereby the IC package comprising the conductive resin composition is formed. An object of the present invention is to provide a conductive resin composition for IC packaging in which a contamination of an IC or the like due to detachment of carbon black or the like is remarkably reduced in a molded article for use.

[0006]

That is, the first aspect of the present invention is as follows.
The present invention relates to (A) a thermoplastic resin selected from at least one of a polyphenylene ether-based resin, a polystyrene-based resin and an ABS-based resin, (B) carbon black, and (C) a siloxane bond in a main skeleton or a side chain. In a conductive resin composition for IC packaging comprising a polymer or a copolymer, (A) 100 parts by weight of the (A) thermoplastic resin, (B) 5 to 50 parts by weight of carbon black, and (C) A polymer or copolymer having a siloxane bond in a main skeleton or a side chain with respect to 100 parts by weight of the total amount of (A) thermoplastic resin and (B) carbon black.
Parts by weight, and (b) the conductive resin composition has a surface specific resistance of 10 ² to 10 ¹⁰ Ω, and
A conductive resin composition for IC packaging, characterized by having a dynamic friction coefficient with a tin-lead alloy (50% by weight of tin) of 0.6 or less by a measurement method according to IS-K-7125.

Hereinafter, the present invention will be described in more detail. In the present invention, (A) a polyphenylene ether-based resin,
A thermoplastic resin selected from at least one of a polystyrene resin and an ABS resin is used, and the polyphenylene ether resin refers to a resin having a polyphenylene ether resin and a polystyrene resin as main components, and a polyphenylene ether resin and a polystyrene resin. Total amount of resin 10
The content of polyphenylene ether resin in 0 parts by weight is 2
The amount is preferably from 8 to 86 parts by weight, and if it is less than 28 parts by weight, 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 a homopolymer or a copolymer described in U.S. Pat. No. 3,383,435.

[0008] The polystyrene resin used in the present invention is a resin mainly composed of a general polystyrene resin or an impact-resistant polystyrene resin and a mixture thereof.
The term "based resin" means a resin mainly composed of a copolymer mainly composed of three components of acrylonitrile-butadiene-styrene.

The carbon black used in the present invention is furnace black, channel black, acetylene black, or the like, and preferably has a large specific surface area and a high level of conductivity can be obtained with a small amount added to the resin. For example, C. F. (Super Conductiv
e Furnace); C. F. (Electri
c Conductive Furnace), Ketjen Black (Lion-AKZO Corporation) and acetylene black. The amount of carbon black to be added is such that the surface specific resistance can be 10 ² to 10 ¹⁰ Ω, and (B) 5 to 50 parts by weight of (B) carbon black per 100 parts by weight of the thermoplastic resin. Is preferred. 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, uniform dispersibility with the resin is deteriorated, and molding processing becomes difficult, and In addition, characteristic values such as mechanical strength are reduced. If the surface resistivity exceeds 10 ¹⁰ Ω, a sufficient antistatic effect cannot be obtained. If the surface resistivity is less than 10 ² Ω, electroconductivity is too good to generate electromotive force due to electromagnetic induction or electrostatic induction.
May be destroyed.

The (C) polymer or copolymer having a siloxane bond in the main skeleton or side chain used in the present invention is (A)
It refers to a so-called silicone resin or silicone rubber having a cycloxane bond (Si-O-Si) in its main skeleton, or (b) a thermoplastic resin grafted with a compound having a cycloxane bond. (A) In order to disperse uniformly in a thermoplastic resin, the average particle size of a so-called silicon resin, silicon rubber, or the like having a cycloxane bond (Si-O-Si) in its main skeleton must be 50 µm or less. Preferably, this may be used as so-called master pellets previously filled in a high concentration in a thermoplastic resin serving as a base, and can also be directly added.For example, silicon powder of Toray Dow Silicone Co., Ltd. The name "Trefill E" is used.
(B) The thermoplastic resin obtained by graft-polymerizing a compound having a cycloxane bond is not particularly limited as long as it can be uniformly dispersed in a polyphenylene ether-based resin, a polystyrene-based resin, and an ABS-based resin. For example, a silicon graft resin manufactured by Dow Corning is used.

(C) The amount of the polymer or copolymer having a siloxane bond in the main skeleton or side chain is preferably 0.1 to 10 parts by weight, particularly preferably 1 to 7 parts by weight. If the addition amount is less than 0.1 part by weight, the effect is insufficient,
It is difficult to make the dynamic friction coefficient with a tin-lead alloy (50 wt% tin) 0.6 or less. If the coefficient of kinetic friction exceeds 0.6, the desorption of carbon black due to abrasion with the IC or the like increases remarkably, thereby contaminating the IC or the like. If the addition amount exceeds 10 parts by weight, the dispersion in the resin becomes non-uniform, resulting in deterioration of the moldability and non-uniformity of the mechanical properties.

Further, the conductive resin composition of the present invention may contain, if necessary, a lubricant, a plasticizer, a processing aid, a reinforcing agent for improving the mechanical properties of a molded article, and the like. Various additives and other resin components can be added.

The conductive resin composition of the present invention has a surface specific resistance of 10 ² to 1 in order to maintain sufficient moldability.
When carbon black is filled so as to be 0 ¹⁰ Ω or less, the melt flow index (JIS-K-7210)
When filled into polyphenylene ether resin, at 230 ° C. under a load of 10 kg, when filled into polystyrene resin, at 200 ° C. under a load of 5 kg, under ABS under a load of 5 kg, 220 ° C. Load 10k
g, respectively, is 0.1 g / 10 min or more.

For kneading and pelletizing the various raw materials such as the resin of the present invention, known methods such as a Banbury mixer and an extruder can be used.

[0015]

The present invention will be described in more detail with reference to the following examples. Examples 1 to 4 Raw materials were weighed at the raw material composition ratios shown in Table 1 and uniformly mixed by a high-speed mixer, kneaded using a φ45 mm vent-type twin-screw extruder, and pelletized by a strand cut method. . Next, the pelletized resin composition was sampled for 500 m using a φ65 mm extruder (L / D = 28).
Sample N was formed into a sheet having a thickness of 500 μm using a T-die having a width of m, and a sample N was formed by an injection molding machine (1
A sample for evaluation was formed into a plate having a thickness of 1 mm × 120 mm square and a test piece for tensile measurement according to 00t). The evaluation results are shown in Tables 3 and 4. In each of the examples, the carbon black did not fall off.

Comparative Examples 1 to 4 In the same manner as in Example 1, the raw materials were 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 φ45 mm vented twin-screw extruder, and pelletized by a strand cut method. Next, a sample M and a sample N were prepared from the pelletized resin composition and evaluated. The evaluation results are shown in Tables 3 and 4. In each comparative example, it was confirmed that carbon black had fallen off.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

[Table 4]

Each sample was evaluated by the following method. (1) Surface specific resistance Both samples M and N were measured with a Loresta surface resistance meter (manufactured by Mitsubishi Yuka Co., Ltd.) to set the distance between the electrodes to 10 mm, and any 10 points in the sample were measured. (2) Breaking point strength and tensile modulus According to JIS-K-7113, for sample M, 2
As for the No. 1 test piece and the sample N, the No. 1 test piece was measured at a tensile speed of 10 mm / min.

(3) Dynamic friction coefficient The measurement was performed in accordance with JIS-K-7125. (4) Existence of carbon falling off QFP 14 mm x 20 m on the surface of each sheet and plate
An m / 64 pin IC was pressed with a load of 100 g and reciprocated 100 times with a stroke of 15 mm. Thereafter, the lead portion of the IC was observed with a microscope. Evaluation was made based on the presence or absence of black deposits such as carbon black on the lead portions. (5) MFI Pellets of Examples and Comparative Examples are JIS-721.
The measurement was performed according to 0.

[0023]

As described above, in the conductive resin composition for IC packaging comprising carbon black and a thermoplastic resin selected from at least one of polyphenylene ether-based resin, polystyrene-based resin and ABS-based resin, In addition, the conductive resin composition further contains a polymer or copolymer having a siloxane bond in a main skeleton or a side chain, thereby causing desorption of carbon black or the like due to abrasion at the time of contact with the IC or the like. It is possible to obtain a conductive resin composition in which contamination of the conductive resin is significantly reduced.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08L 83:04) C08L 83:04) (C08L 55/02 (C08L 55/02 83:04) 83:04)

Claims (5)

(57) [Claims] (A) a thermoplastic resin selected from at least one of a polystyrene resin and an ABS resin,
IC comprising (B) carbon black and (C) a polymer or copolymer having a siloxane bond in the main skeleton or side chain.
In the conductive resin composition for packaging, (A) 100 to 100 parts by weight of the thermoplastic resin (A), 5 to 50 parts by weight of carbon black (B), and (A) the thermoplastic resin and (B) ) Ri weight per 100 parts by weight of carbon black (C) the main skeleton or side chain name contains a polymer or copolymer of 0.1 to 10 parts by weight having a siloxane bond, Po
A conductive resin composition for IC packaging that does not contain a phenylene ether-based resin . (A) a thermoplastic resin selected from at least one of a polystyrene resin and an ABS resin;
IC comprising (B) carbon black and (C) a polymer or copolymer having a siloxane bond in the main skeleton or side chain.
In the conductive resin composition for packaging, (A) 100 parts by weight of the (A) thermoplastic resin, (B) 5 to 50 parts by weight of carbon black, and (A) the thermoplastic resin and (B) (B) a conductive resin comprising 0.1 to 10 parts by weight of a polymer or copolymer having a siloxane bond in a main skeleton or a side chain based on 100 parts by weight of the total amount of carbon black; The surface resistivity of the composition is 10 ²
A to 10 ¹⁰ Omega, and by measuring method pursuant to JIS-K-7125, a tin - dynamic friction coefficient between the lead alloy (tin 50 wt%) is equal to or 0.6 or less, polyphenylene
A conductive resin composition for IC packaging containing no nylene ether-based resin . 3. An IC packaging container comprising the conductive resin composition for IC packaging according to claim 1 or 2. 4. A molded article comprising the conductive resin composition for IC packaging according to claim 1 or 2. 5. A sheet comprising the conductive resin composition for IC packaging according to claim 1 or 2.