JP2001151905A - Resin-made cooling body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synthetic resin-made cooling body which has excellent heat resistance, dimension stability, heat distortion resistance and thermal conductivity. SOLUTION: The resin-made cooling body is formed of a resin composition which contains a polyarylenesulfide (A) and an inorganic filler (B) and which has a thermal conductivity of 1 W/mK or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat radiating plate made of resin, and more particularly, to a heat radiating plate for computer-related parts such as a CPU.

[0002]

2. Description of the Related Art In recent years, electronic devices such as CPUs have increased power consumption and increased heat generation due to an increase in their integration density and operation speed. Therefore, a heat radiation measure is required. Conventionally, as a heat dissipation measure for electronic components mounted on a printed wiring board or the like, a heat dissipation plate is fixed to a package or the like of the electronic component where heat generation is a problem, so that heat generated from the electronic component is dissipated. I have. As the heat radiating plate, one made of aluminum metal is usually used, but it is relatively expensive, the degree of freedom in shape selection is narrow, and it has been an obstacle to downsizing electronic components. When a synthetic resin is used in place of a metal, a heat sink having a large heat dissipation surface can be formed in a complicated shape by injection molding or the like, but has disadvantages such as poor thermal conductivity.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat sink made of synthetic resin which is excellent in heat resistance, dimensional stability, heat deformation resistance and heat conductivity.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to overcome the problems of the prior art, and as a result, polyarylene sulfide contains a specific inorganic filler and has a thermal conductivity of 1 W / When a radiator plate was prepared using a resin composition having a mK or more, it was found that a radiator plate having excellent heat resistance, dimensional stability, heat deformation resistance, and thermal conductivity could be obtained, and the present invention was completed. It is a thing.

That is, the present invention provides a resin heat radiator formed from a resin composition containing a polyarylene sulfide (A) and an inorganic filler (B) and having a thermal conductivity of 1 W / mK or more. It is a board.

Further, according to the present invention, the resin composition is used as an inorganic filler (B) with respect to 100 parts by weight of a polyarylene sulfide (A) as a metal oxide powder (B1) 10 to 60.
The above resin radiator plate containing 0 parts by weight and 10 to 600 parts by weight of the fibrous filler (B2).

The present invention also relates to a metal oxide powder (B1)
Is the above-mentioned resin heat sink made of magnesium oxide or aluminum oxide.

The present invention also provides a fibrous filler (B2)
Is the above-mentioned resin radiator plate which is at least one selected from the group consisting of glass fiber, carbon fiber, wollastonite, potassium titanate and aluminum borate.

A preferred embodiment of the present invention is as follows. (1) The resin composition is polyarylene sulfide (A)
The heat radiation described above, which contains 10 to 500 parts by weight of the metal oxide powder (B1) and 10 to 500 parts by weight of the fibrous filler (B2) as the inorganic filler (B) with respect to 100 parts by weight. Board. (2) The resin composition is a polyarylene sulfide (A)
The heat radiation described above, which contains 20 to 300 parts by weight of the metal oxide powder (B1) and 20 to 300 parts by weight of the fibrous filler (B2) as the inorganic filler (B) with respect to 100 parts by weight. Board. (3) The above-mentioned heat sink in which the thermal conductivity of the resin composition is 1.3 W / mK or more. (4) The above-mentioned heat sink, wherein the polyarylene sulfide is polyphenylene sulfide.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. 1. Resin composition (A) Polyarylene sulfide The polyarylene sulfide used in the present invention (hereinafter referred to as “polyarylene sulfide”)
PAS) is a polymer whose repeating unit substantially consists of -Ar-S- (Ar: an arylene group). Preferably, a polymer having a paraphenylene group as a repeating unit, and a paraphenylene group as a main component and other arylene groups as a minor component, for example, an m-phenylene group, an o-phenylene group, an alkyl-substituted phenylene group, p , P'-diphenylene sulfone group, p, p'-biphenylene group, p, p'-diphenylene ether group, p, p'-diphenylenecarbonyl group, random copolymer and block copolymer having naphthalene group Coalescence. In addition, these polyarylene sulfide resins may be a mixture. The PAS used in the present invention is preferably a linear polymer. However, the PAS partially contains a branched and / or cross-linked structure or a cross-linked polymer, and the melt viscosity is increased by oxidative cross-linking ( Cure) can be used as long as the mechanical properties can be satisfied.

Among these PASs, polyphenylene sulfide (hereinafter sometimes abbreviated as PPS) having a p-phenylene sulfide repeating unit as a main component is excellent in processability, heat resistance and dimensional stability, and It is particularly preferable because it is industrially easily available. Specific examples of the copolymer include a random or block copolymer having a repeating unit of p-phenylene sulfide and m-phenylene sulfide, and a random or block copolymer having a repeating unit of phenylene sulfide and arylene sulfone sulfide. . These PASs are heat resistant,
From the viewpoint of dimensional stability and the like, a crystalline polymer is preferable.

[0012] Among such PASs, a linear PAS can be obtained by the following method. For example,
A method for producing a high-molecular-weight polyarylene sulfide in the presence of a metal salt of a carboxylic acid such as sodium acetate or lithium acetate, which is described in JP-A-6-12332, In a method for producing a PAS by reacting an alkali metal sulfide with a dihalo aromatic compound in an organic amide solvent, the first step is carried out in the presence of 0.5 to 2.4 mol of water per mol of the alkali metal sulfide. The reaction is carried out at a temperature of from 180 to 235 ° C. to give a conversion of the dihaloaromatic compound of from 50 to 98 mol%, followed by the addition of water in the second stage with the presence of 2.5 to 7.0 mol of water. A method for producing a high-molecular-weight polyarylene sulfide by further continuing the reaction at a temperature of 245 to 290 ° C. under an organic solvent described in JP-A-5-222196. The reaction between an alkali metal sulfide and a dihaloaromatic compound in a solvent system is carried out, and during the reaction, a part of the gas phase in the reaction vessel is condensed by cooling the gas phase part of the reaction vessel, and this is converted into a liquid. Method for producing high molecular weight polyarylene sulfide produced by refluxing into a phase
In the reaction of an alkali metal sulfide and a dihaloaromatic compound in an organic amide solvent described in JP-A-195197, the gas phase portion of the reactor is cooled, and after the reaction is completed, a specific amount of alkali is added to the reaction solution slurry. There is a method of producing a high molecular weight polyarylene sulfide by adding an earth metal compound.

In these polymerization methods, a part of the gas phase in the reaction vessel is condensed by cooling the gas phase part of the reaction vessel, and this is refluxed to a liquid phase to produce PAS. A method based on the method described in JP-A-222196 is preferred. For example, a layer having a high water content is formed on the upper portion of the reaction solution by actively cooling the gas phase portion of the reactor and returning a large amount of the reflux liquid rich in water to the upper portion of the liquid phase. As a result, the layer contains a large amount of residual alkali metal sulfide (eg, Na ₂ S), alkali metal halide (eg, NaCl), oligomers, and the like. In a state where the produced PAS and raw materials such as Na ₂ S and by-products are uniformly mixed, the produced PAS
Depolymerization of S also occurs, and by-products of thiophenol are observed. However, by forming a layer having a high water content in the upper portion of the reaction solution, it is considered that factors that hinder the reaction can be truly efficiently eliminated and a high molecular weight PAS can be obtained.

The gas phase portion of the reaction vessel can be cooled by external cooling or internal cooling, and any method can be used as long as it has the effect of increasing the amount of reflux in the vessel. In the case of external cooling, the water / amide solvent mixture condensed on the reaction vessel wall flows into the liquid layer along the reaction vessel wall. Thus, the water-rich mixture accumulates at the top of the liquid phase, keeping the water content relatively high. In the case of internal cooling, the mixture condensed on the cooling surface likewise travels along the cooling device surface or the reactor wall and into the liquid phase.

[0015] The reaction temperature is preferably maintained at a predetermined constant temperature, and the reaction is preferably carried out at a temperature of 230 to 275 ° C for 0.1 to 20 hours. More preferably, 240
1 to 6 hours at a temperature of ２６265 ° C. To obtain a higher molecular weight PAS, it is preferable to use a reaction temperature profile of two or more steps. When performing this two-step operation,
The first stage is preferably performed at a temperature of 195 to 240C. The completion of the first stage is such that the residual ratio of the dihalo aromatic compound in the polymerization reaction system is 1 to 40 mol% and the molecular weight is 3,000.
It is preferable to carry out at a time point within the range of -200,000. Thereafter, the temperature was raised, and the reaction at the final stage was performed at a reaction temperature of 24
It is preferable to carry out for 1 hour to 10 hours within the range of 0 to 270.

Further, dehydration or water addition is performed as necessary so that the amount of water in the alkali metal sulfide in the amide solvent becomes a predetermined amount. The water content is preferably 0.5 to 2.5 mol, particularly 0.8 to 2.5 mol per mol of alkali metal sulfide.
1.2 mol. If it exceeds 2.5 moles, the reaction rate will be low, and the amount of by-products such as phenol will increase in the filtrate after the reaction, and the degree of polymerization will not increase. If the amount is less than 0.5 mol, the reaction rate is too high, and a polyarylene sulfide having a sufficient high molecular weight cannot be obtained.

The organic amide solvent used is a solvent known for PAS polymerization, for example, N-methylpyrrolidone (NMP), N, N-dimethylformamide, N, N
N-dimethylacetamide, N-methylcaprolactam, etc., and mixtures thereof can be used, with NMP being preferred.

Alkali metal sulfides are also known, for example, lithium sulfide, sodium sulfide, potassium sulfide, and mixtures thereof. These hydrates and aqueous solutions may be used. Hydrosulfides and hydrates corresponding to these can be used after being neutralized with the corresponding hydroxides. The dihalo aromatic compound can be selected from, for example, those described in JP-B-45-3368, but is preferably p-dichlorobenzene. Also, if necessary, 1,2,4-trichlorobenzene,
A polyhalo aromatic compound such as 1,3,5-trichlorobenzene can be used in an amount of 5 mol% or less based on the dihalo aromatic compound. As other small additives, a terminal stopper and a monohalo compound as a modifying agent can be used in combination. The PAS thus obtained is separated from by-products by post-treatment methods known to those skilled in the art.

The PAS used as a raw material of the polyarylene sulfide (A) used in the present invention may be an acid-treated PAS. The acid may be either an organic acid or an inorganic acid. Examples of the organic acid include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, benzoic acid, phthalic acid, salicylic acid, acrylic acid, crotonic acid, oleic acid, oxalic acid, maleic acid, and fumaric acid. Can be
Examples of the inorganic acid include hydrochloric acid, sulfuric acid, sulfurous acid, nitric acid, phosphoric acid, boric acid, and carbonic acid. In addition, these acid salts can also be used. Of these, acetic acid and hydrochloric acid are preferred. The acid treatment of the PAS may be an acid treatment of the slurry after the completion of the polymerization reaction, or an acid treatment after filtering and purifying the PAS.

(B) Inorganic Filler The inorganic filler (B) used in the present invention has the same strength as the metal oxide powder (B1) for achieving a thermal conductivity capable of imparting properties as a heat sink. There is a fibrous filler (B2) to be provided, and a metal oxide powder (B1) contributing to improvement in thermal conductivity and a fibrous filler (B2) contributing to strength and dimensional stability are used in combination. Is preferred.

Examples of the metal oxide powder (B1) include powdery magnesium oxide and aluminum oxide, which can be used alone or in combination.

As the fibrous filler (B2), for example,
Glass fiber, carbon fiber, alumina fiber, stainless steel fiber, aluminum fiber, copper fiber, brass fiber, calcium titanate fiber, slag fiber, wollastonite fiber, zonolite fiber, phosphate fiber, calcium sulfate fiber, asbestos fiber, magnesium hydroxide Fiber, silicon carbide fiber, silicon nitride fiber, boron fiber, aluminum borate fiber and the like. These fibrous fillers are
Each of them can be used alone or in combination of two or more. Among the fibrous fillers, one or more fibers selected from glass fiber, carbon fiber, wollastonite, potassium titanate, and aluminum borate are used because of their stability in air and industrial availability. Particularly preferred.

The metal oxide powder (B1) and the fibrous filler (B2) were subjected to surface treatment with a coupling agent such as a silane coupling agent, a titanate coupling agent, and an aluminum coupling agent. It may be something.

The amount of the inorganic filler used in the resin composition is P
With respect to 100 parts by weight of AS, as an inorganic filler (B),
The metal oxide powder (B1) is 10 to 600 parts by weight, preferably 10 to 500 parts by weight, and more preferably 20 to 3 parts by weight.
00 parts by weight, and the fibrous filler (B2) is 10 to 6 parts by weight.
00 parts by weight, preferably 10 to 500 parts by weight, more preferably 20 to 300 parts by weight. If the amount of the metal oxide powder (B1) is less than 10 parts by weight, the thermal conductivity will be low, and if it exceeds 600 parts by weight, dimensional stability and moldability will be poor. When the amount of the fibrous filler (B2) is less than 10 parts by weight, the strength is reduced, and when the amount is more than 600 parts by weight, the moldability deteriorates.

(C) Other Components A silane compound can be added to the polyarylene sulfide resin composition of the present invention, if necessary, in order to improve fluidity and the like. Examples of the silane compound include polysiloxane and a silane coupling agent. Examples of the polysiloxane include modified and / or unmodified polyorganosiloxanes. Specific examples include unmodified polyorganosiloxanes such as polydimethylsiloxane, polymethylphenylsiloxane, and polydimethyl-diphenylsiloxane. Modified polyorganosiloxane partially modified with a functional group such as a hydroxyl group, an amino group, a carboxyl group, an epoxy group, a methacryloxy group, and a mercapto group is exemplified. The viscosity of the polysiloxane is from 100 to 500,000 centistokes, preferably from 1,000 to 100,000 centistokes. Examples of the silane coupling agent include an alkoxysilane having an amino group, an epoxy group, a methacryloxy group, a mercapto group, a vinyl group, a ureide group, and the like. Specifically, γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-
Isocyanate propyl triethoxy silane, vinyl triethoxy silane and the like can be mentioned. These silane compounds can be used alone or in combination of two or more.

Further, the resin composition of the present invention contains an antioxidant, a lubricant, a release agent, a nucleating agent, a flame retardant, a coloring agent, an impact resistance improving agent, as long as the object of the present invention is not impaired.
Thermosetting resins, other thermoplastic resins, and the like can be added.

2. Production of Resin Composition The polyarylene sulfide resin composition used in the present invention can be prepared by equipment and a method generally used for preparing a synthetic resin composition. That is, the method of mixing necessary components is a method in which each component is dry-blended in advance using a Henschel mixer or the like, kneaded using a single-screw or twin-screw extruder, and extruded to form pellets for molding.
It is also possible to use a method of mixing and molding a part of the necessary components as a master batch, a method of dissolving the necessary components in a solution at the time of synthesizing the PAS to a predetermined amount, and then including them.

3. Resin composition The heat sink of the present invention is a molded article of a resin composition containing PAS and the above-mentioned inorganic filler, and has a thermal conductivity of 1 W / mK or more, preferably 1.3 W or more. It is necessary to use, as a material, a composition to which an inorganic filler is added so as to be at least / mK. Thermal conductivity is 1W /
When a heat sink is made using a resin composition of less than mK,
Dissipation of heat becomes difficult, and the temperature rises due to heat generated from inside the electronic component, which is not preferable.

4. Heatsink The heatsink of the present invention can be formed by injecting the resin composition into a mold by injection molding the resin composition. According to the injection molding of the resin composition, a heat sink having a complicated shape can be easily manufactured at low cost. In addition to injection molding, necessary parts may be molded by extrusion molding, compression molding, or the like. The shape of the heat radiating plate can be appropriately determined according to the type and arrangement of each component.

[0030]

The preferred embodiments of the present invention will be described more specifically with reference to the following examples. In addition, the measuring method of a physical property is as follows. (1) Thermal conductivity: measured in accordance with ASTM C201.

Example 1 Polyphenylene sulfide (manufactured by Toprene, T-3A)
G) Magnesium oxide (Kyowa Chemical Industry Co., Ltd.)
30 kg of a mixture obtained by dry blending 15 kg of Kyowa Mag Co., Ltd., with a Henschel mixer, was supplied to a twin-screw kneading extruder, and a glass fiber (GF-GF, manufactured by Nitto Boseki Co., Ltd.)
3J-961) 6 kg was supplied from the side of the extruder and melt-kneaded to obtain a pellet-shaped resin composition. When the thermal conductivity of the obtained resin composition was measured, it was 1.3 W / mK.
Met. CP for PC from the pellet obtained above
A heat sink of U is made by injection molding, and this heat sink is CP
The PC installed in the U unit was used continuously for 500 hours, but it worked without any problem.

Example 2 Polyphenylene sulfide (T-3A, T-3A)
G) 10 kg of aluminum oxide (Sumitomo Chemical Co., Ltd.)
20 kg) of a mixture obtained by dry blending 10 kg with a Henschel mixer is supplied to a twin-screw kneading extruder, and 2 kg of aluminum borate whiskers (manufactured by Shikoku Kasei Kogyo Co., Ltd., Arbolex) are supplied from the side of the extruder and melt-kneaded. Was performed to obtain a pellet-shaped resin composition. When the thermal conductivity of this composition was measured, it was 1.4 W / mK.
From the obtained resin composition pellets, mold a video chip heat sink on a video accelerator board for personal computers,
The video accelerator equipped with the heat sink was inserted into the personal computer and the personal computer was operated. However, there was no problem with continuous use for 500 hours.

Comparative Example 1 Polyphenylene sulfide (manufactured by Toprene, T-3A)
G) 30 kg is supplied to a twin-screw kneading extruder, and 20 kg of glass fiber (manufactured by Nitto Boseki Co., Ltd., GF-3J-961) is supplied from the side of the extruder and melt-kneaded to obtain a pellet-shaped resin composition. Obtained. When the thermal conductivity of the obtained resin composition was measured, it was 0.6 W / mK. A heat sink of a CPU for a personal computer was prepared by injection molding from the pellets obtained above, and a personal computer in which the heat sink was installed in a CPU unit was used continuously for 500 hours.

[0034]

According to the present invention, heat resistance, dimensional stability,
A heat sink made of synthetic resin having excellent heat deformation resistance and heat conductivity is provided. The heat sink of the present invention is particularly suitable for a heat sink of a computer-related component such as a CPU. Further, since the heat sink of the present invention is obtained by melt-molding a resin composition, the degree of freedom in shape is extremely high and the productivity is extremely high as compared with a metal heat sink.

Continued on the front page F-term (reference) 4F071 AA62 AB03 AB18 AB20 AB27 AB28 AB30 AD01 AD02 AE17 AF44Y AH12 BC01 4J002 CN011 DA017 DA077 DA097 DC007 DE076 DE077 DE146 DE147 DE187 DG057 DH047 DJ007 DJ027 DK007 DL007 FA047 FD017 G05FD

Claims (4)

[Claims] 1. A resin radiator plate comprising a resin composition containing a polyarylene sulfide (A) and an inorganic filler (B) and having a thermal conductivity of 1 W / mK or more. 2. A resin composition comprising, as inorganic filler (B), 10 to 600 parts by weight of metal oxide powder (B1) and fibrous filler (100 parts by weight) per 100 parts by weight of polyarylene sulfide (A). B2) The resin radiator plate according to claim 1, comprising 10 to 600 parts by weight. 3. The resin radiator plate according to claim 1, wherein the metal oxide powder (B1) is magnesium oxide or aluminum oxide. 4. The fibrous filler (B2) is a glass fiber,
The resin radiator plate according to any one of claims 1 to 3, wherein the resin radiator plate is at least one selected from the group consisting of carbon fiber, wollastonite, potassium titanate, and aluminum borate.