JPH02308855A - Resin composition for sealing electronic part - Google Patents

Abstract

PURPOSE:To provide a resin composition achieving a low stress without deteriorating its heat resistance, flowability, etc., and useful for sealing electronic parts by compounding a poly-arylene sulfide resin with a specific amount of (graft-modified) poly (4-methyl-1-pentene) resin, etc. CONSTITUTION:A resin composition for sealing electric parts comprises (A) a polyarylene sulfide resin, (B) poly (4-methyl-1-pentene) resin and/or a modified poly (4-methyl-1-pentene) resin graft-modified with an unsaturated carboxylic acid (derivative) in a graft amount range of 0.01-10wt.%, (C) a reinforcing and/or a filler and (D) an organic silane in an A/B weight ratio of 99/1-86/14 in an (A+B) content of >=25wt.%, a C content of 74.99wt.% and a D content of 0.01-5%. The resin composition has a melt viscosity of <=300 poises at 320 deg.C. The component C includes that having an aspect ratio of >=50 or that having an average particle side of >=300mum in an amount of <=20wt.% based on the whole composition.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a resin composition for encapsulating electronic components that achieves low stress without sacrificing strength, heat resistance, fluidity, etc. The present invention also relates to an electronic component having excellent reliability using the composition as a packaging material.

(Prior art and problems to be solved by the invention) Polyarylene sulfide resin (hereinafter referred to as PAS) is known as an ensuring plastic with excellent chemical resistance, heat resistance, flame retardance, and electrical properties. It is widely used in various fields.Recently, it has been attracting attention as a sealing material for electronic components. There was a problem that the characteristics changed due to the stress caused by the sealing of the component bag, which was weak in the sealing, and the +1zL sealing, and a lower stress and lower modulus of elasticity were desired.

Conventionally, attempts have been made to solve this problem by adding elastic bodies such as rubber to PAS to lower the elastic modulus, but conventional techniques generally sacrifice strength, heat resistance, fluidity, etc. Ta. In other words, PAS has a very high melt processing temperature, but SBR does not.

NBR, isoprene rubber, etc. contain multiple aliphatic double bonds that are susceptible to thermal deterioration, so compositions containing these are thermally deteriorated during molding and processing, resulting in reduced strength and poor appearance. Furthermore, although acrylic rubber has almost no aliphatic double bonds, ester bonds and the like are susceptible to heat deterioration, and compositions containing such rubbers are unsuitable because they result in decreased strength and poor product appearance. Olefin rubbers such as EPR have almost no aliphatic double bonds and therefore suffer relatively little thermal deterioration, but their viscosity increases, making them unsuitable as sealants.

(Means for solving the problem) As a result of the inventors' intensive study on the above situation,
Poly(4-methyl-1-pentene) resin (hereinafter referred to as PMP) and/or graft-modified poly(4-methyl-1-pentene) resin (hereinafter referred to as PMP) is added to the system consisting of PAS, reinforcing material and/or filler, and organic silane. It has been found that by appropriately adding pentene resin (hereinafter referred to as modified PMP), stress can be reduced without sacrificing the heat resistance, fluidity, or strength properties of the RAS composition.

That is, the present invention comprises ('A) polyarylene sulfide resin, (B) poly
The amount of grafting of (4-methyl-1-pentene) resin and unsaturated carboxylic acid or derivative thereof is 0.01 to
Modified poly(4
- methyl-1-pentene) resin, (C) reinforcing material and/or filler (D) organic silane, and the weight ratio of (A) and (B) is (A).
/ (B) -99/1 to 86/14, and (A) + (B) is 25% by weight or more and (C) is 7% by weight in the whole composition.
4.99% by weight or less, (D) is 0.01 to 5% by weight, and the melt viscosity at 320°C (shear rate of 10' sec) is 3000 poise or less, a resin composition for encapsulating electronic components; The present invention also relates to an electronic component sealed with the composition and having excellent reliability.

The PAS used in the present invention is uncrosslinked or partially crosslinked PA
S and mixtures or modified products thereof, the melt flow rate of the PAS is ASTtl D1238-74 (31
2-60000 g/1 at 5.6℃, 5 kg load)
It has 0 minutes.

Polyphenylene sulfide (hereinafter referred to as PPS) containing 70 mol % or more of the unit is preferred because it provides a composition with excellent properties. As for the polymerization method of PPS, p=
Polymerization method in the presence of dichlorobenzene sulfur and sodium carbonate, polymerization method in the presence of thorium sulfide or sodium bisulfide and thorium hydroxide or hydrogen sulfide and thorium hydroxide in a polar solvent, p-chlorobenzene Examples include self-condensation of ruthiophenol, and sodium sulfide and p
- A method in which dichlorobenzene is reacted is suitable. At this time, in order to adjust the degree of polymerization, it is a preferable method to add an alkali metal salt of carboxylic acid or sulfonic acid, or to add alkali hydroxide. 30 as a copolymer component
1 mole where R is alkyl, nitro, phenyl, alkoxy,
(representing a metal base of carboxylic acid or carbonic acid), may be contained as a trifunctional phenyl sulfide bonded block copolymer or as a random copolymer as long as it does not significantly affect the crystallinity of the polymer, but preferably The copolymerization component is preferably 10 mol% or less. In particular, when trifunctional or more functional phenyl, piphenyl, naphthyl sulfide bonds, etc. are selected for copolymerization, the amount is preferably 3 mol% or less, more preferably 1 mol% or less.

Such PPS can be produced by common manufacturing methods, such as (1) reaction of a halogen-substituted aromatic compound with an alkali sulfide (see U.S. Pat. No. 2,513,188, Japanese Patent Publication No. 44-27671 and Japanese Patent Publication No. 45-3368) (2) ) Condensation reaction of thiophenols in the presence of an alkali catalyst or copper salt (US Patent No. 3,274,165, British Patent No. 1160)
660) (3) Condensation reaction of aromatic compounds with sulfur chloride in the presence of a Lewis acid catalyst (Japanese Patent Publication No. 46-272
No. 25, Belgian Patent No. 29437), etc., and can be arbitrarily selected depending on the purpose.

If the viscosity of PMP and/or modified PMP used in the present invention is high, dispersion will be poor, so the melt flow rate is 20 to 500 g'/10 minutes (260 ° C. 15 kg
load), preferably 30 to 4. OOg/10 minutes is good.

PMP and/or modified PMP has good heat resistance, as well as excellent electrical properties and chemical resistance, so even when blended with PAS, it is not as effective as PAS when blended with conventional elastic materials such as rubber. without impairing its excellent properties.

PMP is a polyolefin whose main constituent is -(cll-c■2) - □ (Jl(CH3)z), and is a homopolymer of 4-methyl-1-pentene or within the scope of the present invention. 4-Methyl-neepentene and other α-olefins such as ethylene, propylene, 1-butene, 1
-hexene, 1-octene, 1-decene, 1-tetradecene, 1-octadecene, etc. or aromatic vinyl hydrocarbons, such as styrene, α-methylstyrene, ○-methylstyrene, P-methylstyrene, 1,3-dimethylstyrene , 85 mol% or more of 4-methyl-1-pentene, preferably 90 mol%, in a copolymer with hinylnaphthalene, etc.
Those containing the above can be used, and they may or may not have a crosslinked structure.

Preferred unsaturated carboxylic acids to be grafted onto the PMP used in the present invention include acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and butenedicarboxylic acid. Examples of derivatives thereof include alkyl esters, acid anhydrides, imides, etc. Among these, acid anhydrides and imides are preferred.

Preferred specific examples of unsaturated carboxylic acids or derivatives thereof include maleic acid, fumaric acid, maleic anhydride, itaconic anhydride, citraconic anhydride, maleic acid imide, itaconic acid imide, silaconic acid imide, etc. In particular, maleic anhydride, itaconic anhydride, and maleic acid imide can be preferably used.

The amount of graft reaction of unsaturated carboxylic acid monomer is 0.01
-10% by weight, preferably 0.05-5% by weight. If the graft reaction amount of the unsaturated carboxylic acid monomer is less than 0.01% by weight, the toughness will not be improved sufficiently, and if it exceeds 10% by weight, the heat resistance and moisture resistance of PAS will be impaired. Both of these cases are unfavorable. Incidentally, the graft reaction referred to here refers to a reaction in which an unsaturated carbonic acid or a derivative thereof is combined with an unmodified conjugated diene hydrogenated polymer or a conjugated diene/aromatic hydrocarbon hydrogenated copolymer and sometimes with an unsaturated compound having the above-mentioned functional group. How to copolymerize,
There is a method of grafting using a reaction vessel or an extruder in the presence of PMP, an unsaturated compound having the above-mentioned functional group, or peroxide, but the method is not limited thereto.

The PMP and/or modified PMP can contain a heat stabilizer, and PMP modified with an epoxy group, an amine group, a hydroxyl group, etc. can also be used as long as there is no adverse effect.

The amount of PMP and/or modified PMP added to PAS is PAS/PMP and/or modified PMP=99/
1 to 86/14 (weight ratio). If the amount of PMP and/or modified PMP added is less than 1% by weight, the effect of reducing stress will be small, and if it exceeds 14% by weight, the thermal stability of the composition will decrease, the strength will decrease, or bleeding may occur. This is undesirable as it may cause the appearance to deteriorate.

A reinforcing material and/or a filler are used in the composition of the present invention to improve the physical properties as a sealing material. Its usage proportion is 74.99% or less in the total composition, preferably 5% or more by weight7.
It is 4.99% by weight or less.

If the amount used exceeds the above range, the viscosity will increase and the adhesion of the lead interface will be adversely affected when sealed, which is not preferable.

Furthermore, among the reinforcing materials and/or fillers, those with an aspect ratio of 50 or more and those with an average particle size of 300 μm or more are preferably in a total amount of 20% by weight or less in the entire composition. As a result, it can have sufficient fluidity to seal electronic components, and the reliability of the sealed electronic components can also be ensured.

The reinforcement used is in the form of fibers or scales.

Examples of fibrous reinforcing materials include glass fiber, wollastonite, potassium titanate fiber, aramid fiber, silica fiber, alumina fiber, silica/alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber,
Examples include gypsum fibers, polyester fibers, polyethylene fibers, polyacrylic fibers, fluorine fibers, phenol fibers, processed mineral fibers, and particularly preferred are glass fibers, wollastonite, and silica/alumina fibers.

Examples of the scaly reinforcing material include glass flakes, silica flakes, natural mica, and synthetic mica, and glass flakes made of E glass, silica flakes, and synthetic mica are particularly preferably used as the sealant.

The filling material is an inorganic material having a powder-like (pulverized material), bead-like, or balloon-like shape.

Specific examples include the following. They may be used alone or in combination, but are not necessarily limited to these.

For example, silica, diatomaceous earth, alumina titanium oxide, iron oxide, zinc oxide, magnesium oxide, antimonic acid, antimony oxide, barium ferrite, strontium ferrite, beryllium oxide, pumice, pumice balloon, lead oxide, bismuth oxide, zirconium oxide, Oxides such as manganese dioxide, tin dioxide, pallium oxide, and iron sesquioxide, hydroxides such as aluminum hydroxide, magnesium hydroxide, and basic magnesium carbonate, carbonates such as calcium carbon, magnesium carbonate, dolomite, and dawsonite, and sulfuric acid. Calcium, barium sulfate, ammonium sulfate,
Sulfuric acid or sulfites such as calcium sulfite, zinc sulfide,
Sulfides such as calcium sulfide, strontium sulfide, cadmium sulfide, barium sulfide, talc, clay, mica, glass balloons, glass beads, calcium silicate,
Examples include silicates such as montmorillonite and bentonite, carbon blank, graphite, molybdenum sulfide, boron, silicon carbide, lead zirconate titanate, zinc borate, barium metaborate, calcium borate, and sodium borate. Preferably, they are amorphous or crystalline silica, E-glass, powder (pulverized product) of magnesium oxide, beads, and balloons.

In the present invention, it is preferable to add a silane, usually called a silane camping agent, for the purpose of improving moisture resistance and strength properties. Examples include silane and herosilane. The amount of the silane coupling agent added is 0.01 to 5% by weight based on the total composition.

Furthermore, titanate-based, zirconate-based,
Zircoaluminate-based and aluminum chelate compound-based camping agents can also be added.

In the present invention, in order to further improve adhesion, unmodified and/or modified silicone oil, polyamide, hydrogenated polymer of conjugated diene, and/or hydrogenated polymer of conjugated diene and aromatic vinyl hydrocarbon, (or) a modified product in which an unsaturated carboxylic acid, an unsaturated compound containing a hydroxyl group, an unsaturated compound containing an amino group, an unsaturated acid anhydride, an unsaturated compound containing an epoxy group, or a derivative thereof is grafted onto the hydrogenated polymer; Amide compounds such as bis fatty acid amide and bis aromatic amide, esters such as fatty acid lower alcohol ester, fatty acid polyhydric alcohol ester, and ester wax can be added.

The composition of the present invention may also contain other polymers such as polysulfone, polyallylsulfone,
Added polyether sulfone, polyester, polyolefin, polystyrene, polymethylpentene, polycarbonate, polyphenylene oxide, polyarylate, phenoxy resin, fluororesin, silicone rubber, silicone resin, fluorine rubber, nitrile rubber, epoxy resin, liquid crystal polymer, etc. It's okay. Furthermore, suitable amounts of known additives such as heat stabilizers, antioxidants, corrosion inhibitors, fluidity improvers, lubricants, mold release agents, colorants, epoxy compounds, etc. can be added.

In particular, alkali metal carbonates and hydroxides such as sodium carbonate, lithium carbonate, lithium hydroxide, zinc oxide, lead oxide, magnesium oxide, barium oxide, dolomite, γ-alumina, and hydrotalcites are used as corrosion inhibitors. It is preferable to add 0.1 to 10% by weight. Among these, zinc oxide, γ-alumina, and dolomite are particularly preferred in terms of improving the reliability of the pathogage material.

The composition according to the present invention has a temperature of 320° C. (shear rate 103 se
It is preferable that the melt viscosity in 1) is as low as 3000 poise or less for use as a sealing material for electronic components.

(Effects of the Invention) The polyarylene sulfide resin composition for encapsulating electronic components of the present invention can mainly encapsulate electronic components by methods such as injection molding, transfer molding, compression molding, and dipping. Examples of the electronic components For example, IC, hybrid IC, transistor, diode, capacitor, resistor, thyristor, coil, varistor, connector, transducer-1 crystal oscillator, fuse, rectifier, power supply, switch, various sensors, relay, surge absorber, etc. These include pin grid arrays, leadless chip carriers, leaded chip carriers, and composite parts thereof.

It is particularly suitable for use in coil components that require low stress, network resistors with ceramic substrates that require crack resistance, and chip components that are becoming smaller and thinner.

〔Example〕

Hereinafter, it will be explained in detail using Examples and Comparative Examples.

Examples 1 to 5, Comparative Examples 1 to 3 ASTM D 1238-74 (315,6°C, 5
5000g in melt flow rate measured with kg load)
/10 minutes, poly(4-methylpentene-1) (TPX, manufactured by Mitsui Petrochemical Industries, Ltd.), reinforcing materials, fillers, silane coupling agents, etc. were added as shown in Table 1. The mixture was blended with sea urchin, then triblended using a Henschel mixer, melt-kneaded using a 6011 extruder at 320°C, extruded into strands, and cut into pellets.

For each pellet/nod, a test piece for measuring physical properties was prepared using a 1-ounce injection molding machine at a cylinder temperature of 320°C and a mold temperature of 150°C. The results are shown in Table-1. In addition, after sealing the chip coil under the same temperature conditions as above, the inductance was measured to confirm whether there was any functional deterioration due to sealing.

(1) Fiber diameter 13 μm, average fiber length 200 μm (2) Average particle size 30 μm (3) Average thickness 4 μm, average diameter 40 μm (4) Polymethylpentene resin melt flowray manufactured by Mitsui Petrochemical Industries, Ltd.) 180 g/
10 minutes (260℃15kg>(5) 2.5 parts by weight of maleic anhydride per 100 parts by weight of 4-methyl-pentene polymer
Part by weight and 0.1 part by weight of Bar Hexa 25B (manufactured by NOF) were uniformly mixed in a Henschel mixer, and this mixture was
Extruded using a zero-tsuru extruder at a cylinder temperature of 250°C,
A modified 4-methyl-pentyl polymer was obtained. Unreacted maleic anhydride was removed from the obtained modified polymer, and the amount of maleic anhydride added was measured by titration with sodium methylate and found to be 1.4% by weight. Further, the melt flow rate was 150 g/10 minutes (260° C. 15 kg).

(7) Inductance change is It is expressed as Lo: Initial value (after molding) L, after molding Smaller is preferable.

The composition of the present invention was able to achieve a decrease in elastic modulus and viscosity without decreasing strength, and when a coil was sealed, there was no deterioration in initial properties and showed good results.

Claims (1)

[Claims] 1. The grafting amount of (A) polyarylene sulfide resin, (B) poly(4-methyl-1-pentene) resin and/or unsaturated carboxylic acid or its derivative is 0.01 to 10 It is composed of a modified poly(4-methyl-1-pentene) resin graft-modified in a range of % by weight, (C) a reinforcing material and/or a filler (D) an organic silane, and the above (A) and (B) The weight ratio is (A)
/(B)=99/1 to 86/14, and (A)+(B) is 25% by weight or more and (C) is 74.9% by weight in the whole composition.
9% by weight or less, (D) is 0.01 to 5% by weight, and the melt viscosity at 320°C (shear rate 10^3sec^-^1) is 300 poise or less. . 2. Among the reinforcing materials and/or fillers, those with an aspect ratio of 50 or more and those with an average particle size of 300 μm or more are in a total amount of 20% by weight or less in the entire composition. Resin composition. 3. An electronic component sealed with the resin composition according to claim 1 or 2.