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US4615741A Expired / Lapsed US ⏱️ 0.0 years remaining

Filler for electronic element encapsulation resin and electronic element encapsulation resin composition containing the same

Assignee: Denka Co Ltd
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Filing: 1984-11-08
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Granted: 1986-10-07
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Expires: 2004-11-08
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Abstract

Abstract According to the invention, a filler for an electronic element encapsulation resin composition is provided. The filler comprises 5 to 95 parts by weight of fused silica beads of generally spherical form and 95 to 5 parts by weight of crushed particles of fused silica of rugged form. The resin composition admixed with the filler has excellent fluidity without the formation of burs when molded.

Inventors

  • 👤 Akira Kobayashi
  • 👤 Ryoichi Ide
  • 👤 Hirotaka Koga

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 14:06
CPC Classifications
C; C08; C08K; C08K7/00; C08K7/16; C08K7/18; C08K3/00; C08K3/34; C08K3/36; C08K7/20; C08L; C08L87/00; H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/285; H05K7/00; H05K7/005; H10; H10W; H10W74/00; H10W74/40; H10W74/47; H10W74/473; C08K2201/00; C08K2201/016; H05K2201/00; H05K2201/02; H05K2201/0203; H05K2201/0206; H05K2201/0209; H05K2203/00; H05K2203/13; H05K2203/1305; H05K2203/1316

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 146 words
A filler for an electronic element encapsulation resin composition, comprising: 5 to 95 parts, by weight, of fused silica beads each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of beads each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each bead to the smallest diametral length thereacross being 1 to 1.5; and 95 to 5 parts, by weight, of crushed particles of fused silica each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of particles each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each crushed particle to the smallest diametral length thereacross being 1.6 to 3.0.
Claim 2
Dependent Claim 146 words
A filler for an electronic element encapsulation resin composition, comprising: 5 to 95 parts, by weight, of fused silica beads each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of beads each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each bead to the smallest diametral length thereacross being 1 to 1.5; and 95 to 5 parts, by weight, of crushed particles of fused silica each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of particles each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each crushed particle to the smallest diametral length thereacross being 1.6 to 3.0.
Claim 3
Dependent Claim 27 words
The filler as recited in claim 1, wherein the fused silica forming said beads and said crushed particles contains not more than 100 ppm of alkali ingredients.
Claim 4
Dependent Claim 30 words
The filler as recited in claim 1, wherein the fused silica forming said beads and said crushed particles has an SiO 2 purity of not less than 97 wt %.
Claim 5
Dependent Claim 53 words
The filler as recited in claim 1, wherein said fused silica beads are prepared by spraying quartz powder or silica powder together with a combustible gas and oxygen to form mists of molten silica at a temperature of not lower than 1750° C. followed by cooling the mists to form generally spherical beads.
Claim 6
Dependent Claim 52 words
The filler as recited in claim 1, wherein said crushed particles are prepared by the steps of crushing an ingot of fused silica by a crusher, screening the crushed silica to select lumps having desired dimensions, subjecting the selected lumps to magnetic separation and acid treatment, and then pulverizing said selected lumps.
Claim 7
Dependent Claim 162 words
A thermosetting resin composition for encapsulating an electronic element and containing 30 to 80 wt % of a fused silica filler, said fused silica filler comprising: 5 to 95 parts, by weight, of fused silica beads each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of beads each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each bead to the smallest diametral length thereacross being 1 to 1.5; and 95 to 5 parts, by weight of crushed particles of fused silica each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of particles each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each crushed particle to the smallest diametral length thereacross being 1.6 to 3.0.
Claim 8
Dependent Claim 162 words
A thermosetting resin composition for encapsulating an electronic element and containing 30 to 80 wt % of a fused silica filler, said fused silica filler comprising: 5 to 95 parts, by weight, of fused silica beads each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of beads each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each bead to the smallest diametral length thereacross being 1 to 1.5; and 95 to 5 parts, by weight of crushed particles of fused silica each having the largest particle size of substantially not more than 149 μm and containing not less than 80 wt % of particles each having particle size within the range of from 1 to 149 μm, the ratio of the largest diametral length across each crushed particle to the smallest diametral length thereacross being 1.6 to 3.0.
Claim 9
Dependent Claim 28 words
The resin composition as recited in claim 6, wherein said thermosetting resin is selected from the group consisting of epoxy resins, silicone resins, phenol resins and polyester resins.
Claim 10
Dependent Claim 17 words
The resin composition as recited in claim 6, further comprising at least one of waxes and pigments.
Claim 11
Dependent Claim 15 words
An electronic element encapsulated in a resin composition containing a filler according to claim 1.

References Cited (Backward Citations)

US3985842A Cited
US3975757A Cited
US4248920A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-10-06 1990-04-07 1990-10-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-10-06 1994-04-07 1994-10-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-10-06 1998-04-07 1998-10-07 $7700.00 Window Closed / Lapsed

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