US5965245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prepreg for printed circuit board
Assignee: Resonac Corp
•
Filing: 1996-09-13
•
Granted: 1999-10-12
•
Expires: 2016-09-13
Abstract
Abstract A prepreg comprising a semi-cured thermosetting resin and electrically insulating whiskers or short fibers dispersed in said semi-cured thermosetting resin, and if necessary, a carrier film attached or bound to said prepreg is suitable for producing multilayer printed circuit boards of reduced thinness, high wiring density and high connection reliability with high productivity and low production cost.
Inventors
- 👤 Norio Okano
- 👤 Kazuhito Kobayashi
- 👤 Akishi Nakaso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:04
CPC Classifications
C; C08; C08K; C08K7/00; C08K7/02; H; H05; H05K; H05K1/00; C08J; C08J5/00; C08J5/24; C08J5/248; H05K1/02; H05K1/03; H05K1/0313; H05K1/0353; H05K1/0373; H05K2201/00; H05K2201/01; H05K2201/0137; H05K2201/0145; H05K2201/02; H05K2201/0203; H05K2201/0206; H05K2201/0209; H05K2201/0212; H05K2201/0242; H05K2201/0248; H05K2201/0251; H05K2201/0275; H05K2201/0278; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/249921; Y10T428/249924; Y10T428/24994; Y10T428/249994; Y10T428/249995; Y10T428/26; Y10T428/268; Y10T428/269; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294; Y10T428/2942; Y10T428/2949; Y10T428/31504; Y10T428/31511; Y10T428/31529
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
115 words
A prepreg for printed circuit boards comprising a semi-cured thermosetting resin and electrically insulating whiskers or short fibers, except for glass fibers, dispersed in said semi-cured thermosetting resin, said thermosetting resin having no film-forming ability by itself, yet which has a film-forming ability when having said electrically insulating whiskers or short fibers dispersed therein, said whiskers having an average length of 100 μm or less and said short fibers having an average length of 100 times or less of an average diameter of the short fibers, said average diameter of the short fibers being in a range of 0.1 μm to 15 μm, whereby migration of copper ions along the whiskers or fibers is prevented.
Claim 2
Dependent Claim
115 words
A prepreg for printed circuit boards comprising a semi-cured thermosetting resin and electrically insulating whiskers or short fibers, except for glass fibers, dispersed in said semi-cured thermosetting resin, said thermosetting resin having no film-forming ability by itself, yet which has a film-forming ability when having said electrically insulating whiskers or short fibers dispersed therein, said whiskers having an average length of 100 μm or less and said short fibers having an average length of 100 times or less of an average diameter of the short fibers, said average diameter of the short fibers being in a range of 0.1 μm to 15 μm, whereby migration of copper ions along the whiskers or fibers is prevented.
Claim 3
Dependent Claim
19 words
A prepreg according to claim 1, wherein the whiskers have a modulus of elasticity of 200 GPa or more.
Claim 4
Dependent Claim
13 words
A prepreg according to claim 1, wherein the whiskers are aluminum borate whiskers.
Claim 5
Dependent Claim
27 words
A prepreg according to claim 1, wherein said semi-cured thermosetting resin, having the electrically insulating whiskers or short fibers dispersed therein, is provided on a carrier film.
Claim 6
Dependent Claim
36 words
A prepreg according to claim 4, wherein the electrically insulating whiskers are dispersed in the thermosetting resin, and wherein said thermosetting resin is formed on a roughened surface of a copper foil as the carrier film.
Claim 7
Dependent Claim
41 words
A prepreg according to claim 5, wherein the whiskers have an average diameter of 0.3 μm to 3 μm, and the whiskers have an average length in a range of from 10 times as large as the average diameter 100 μm.
Claim 8
Dependent Claim
13 words
A prepreg according to claim 5, wherein the whiskers are aluminum borate whiskers.
Claim 9
Dependent Claim
36 words
A prepreg according to claim 4, wherein the thermosetting resin has electrically insulating short fibers dispersed therein, and wherein said thermosetting resin is formed on a roughened surface of a copper foil as the carrier film.
Claim 10
Dependent Claim
48 words
A prepreg according to claim 8, wherein the short fibers are at least one member selected from the group consisting of short fibers of aramide fibers, ultra-high molecular weight polyethylene fibers, polyarylate fibers, poly-p-oxybenzoyl whiskers, poly-2-oxy-6-naphthol whiskers, polyoxymethylene whiskers, alumina fibers, magnesia fibers, silica fibers, and zirconia fibers.
Claim 11
Dependent Claim
16 words
A prepreg according to claim 1, wherein said whiskers have been surface-treated with a coupling agent.
Claim 12
Dependent Claim
28 words
A prepreg according to claim 1, wherein said electrically insulating whiskers or short fibers are included in the prepreg in a range of 5% to 50% by volume.
Claim 13
Dependent Claim
45 words
A prepreg according to claim 1, wherein said thermosetting resin having no film-forming ability is selected from the group consisting of epoxy resins, polyimide resins, bismaleimide-triazine resins, phenol resins, melamine resins, silicone resins, unsaturated polyester resins, polyamide resins, cyanic acid ester resins and isocyanate resins.
Claim 14
Dependent Claim
25 words
A prepreg according to claim 12, wherein the thermosetting resin has electrically insulating whiskers dispersed therein, and said prepreg does not include a carrier film.
Claim 15
Dependent Claim
42 words
A prepreg according to claim 13, wherein the whiskers have an average diameter of 0.3 μm to 3 μm, and the whiskers have an average length in a range of from 10 times as large as the average diameter to 100 μm.
Claim 16
Dependent Claim
13 words
A prepreg according to claim 13, wherein the whiskers are aluminum borate whiskers.
Claim 17
Dependent Claim
36 words
A prepreg according to claim 13, wherein said thermosetting resin having no film-forming ability is selected from the group consisting of bismaleimide-triazine resins, epoxy resins with no film-forming ability, and polyimide resins with no film-forming ability.
Claim 18
Dependent Claim
30 words
A prepreg according to claim 12, wherein the thermosetting resin has electrically insulating whiskers dispersed therein, said thermosetting resin, having electrically insulating whiskers therein, being formed on a carrier film.
Claim 19
Dependent Claim
19 words
A prepreg according to claim 17, wherein the whiskers have a modulus of elasticity of 200 GPa or more.
Claim 20
Dependent Claim
38 words
A prepreg according to claim 17, wherein the whiskers are at least one member selected from the group consisting of aluminum borate whiskers, wollastonite whiskers, potassium titanate whiskers, basic magnesium sulfate whiskers, silicon nitride whiskers and α-alumina whiskers.
Claim 21
Dependent Claim
42 words
A prepreg according to claim 17, wherein the whiskers have an average diameter of 0.3 μm to 3 μm, and the whiskers have an average length in a range of from 10 times as large as the average diameter to 100 μm.
Claim 22
Dependent Claim
36 words
A prepreg according to claim 17, wherein said thermosetting resin having no film-forming ability is selected from the group consisting of bismaleimide-triazine resins, epoxy resins with no film-forming ability, and polyimide resins with no film-forming ability.
Claim 23
Dependent Claim
53 words
A prepreg according to claim 1, wherein said thermosetting resin having no film-forming ability is selected from the group consisting of epoxy resins with no film-forming ability, bismaleimide-triazine resins, polyimide resins with no film-forming ability, phenol resins, melamine resins, silicone resins, unsaturated polyester resins, cyanic acid ester resins, isocyanate resins and polyamide resins.
Claim 24
Dependent Claim
12 words
A prepreg according to claim 1, wherein said prepreg includes said whiskers.
Claim 25
Dependent Claim
13 words
A prepreg according to claim 1, wherein said prepreg includes said short fibers.
Claim 26
Dependent Claim
138 words
A prepreg for printed circuit boards comprising a semi-cured thermosetting resin composition and electrically insulating whiskers or short fibers, except for glass fibers, dispersed in said semi-cured thermosetting resin composition, said thermosetting resin composition comprising an epoxy resin, a curing agent for the epoxy resin and a curing accelerator, and said epoxy resin having no film-forming ability by itself but the resin composition with said electrically insulating whiskers or short fibers dispersed therein having a film-forming ability, said whiskers having an average length of 100 μm or less and said short fibers having an average length of 100 times or less of an average diameter of the short fibers, said average diameter of the short fibers being in a range of 0.1 μm to 15 μm, whereby migration of copper ions along the whiskers or fibers is prevented.
Claim 27
Dependent Claim
138 words
A prepreg for printed circuit boards comprising a semi-cured thermosetting resin composition and electrically insulating whiskers or short fibers, except for glass fibers, dispersed in said semi-cured thermosetting resin composition, said thermosetting resin composition comprising an epoxy resin, a curing agent for the epoxy resin and a curing accelerator, and said epoxy resin having no film-forming ability by itself but the resin composition with said electrically insulating whiskers or short fibers dispersed therein having a film-forming ability, said whiskers having an average length of 100 μm or less and said short fibers having an average length of 100 times or less of an average diameter of the short fibers, said average diameter of the short fibers being in a range of 0.1 μm to 15 μm, whereby migration of copper ions along the whiskers or fibers is prevented.
Claim 28
Dependent Claim
79 words
A prepreg according to claim 25, wherein the epoxy resin is at least one member selected from the group consisting of bisphenol A epoxy resin, bisphenol F epoxy resins, bisphenol S epoxy resins, phenol novolak epoxy resins, cresol novolak epoxy resins, bisphenol A novolak epoxy resins, salicylaldehyde novolak epoxy resins, bisphenol F novolak resins, alicyclic epoxy resins, glycidyl ester epoxy resins, glycidylamine epoxy resins, hydration epoxy resins, isocyanurate epoxy resins, aliphatic cyclic epoxy resins, halides thereof, and hydrides thereof.
Claim 29
Dependent Claim
43 words
A prepreg according to claim 25, wherein the curing agent is at least one member selected from the group consisting of dicyandiamide, bisphenol A, bisphenol F, polyvinyl phenol, phenol novolak resin, bisphenol A novolak resin, and halides or hydrides of these phenol resins.
Claim 30
Dependent Claim
31 words
A prepreg according to claim 25, wherein the curing accelerator is at least one member selected from the group consisting of imidazoles, organic phosphorus compounds, tertiary amines, and quaternary ammonium salts.
Claim 31
Dependent Claim
15 words
A prepreg according to claim 25, wherein said prepreg does not include a carrier film.
Claim 32
Dependent Claim
33 words
A prepreg according to claim 25, wherein said prepreg is formed on a carrier film, with the resin composition having the whiskers or short fibers dispersed therein being provided on the carrier film.
Claim 33
Dependent Claim
37 words
A prepreg according to claim 30, wherein said carrier film is a copper foil having a roughened surface, and wherein the resin composition having the whiskers or short fibers dispersed therein is provided on the roughened surface.
Claim 34
Dependent Claim
42 words
A prepreg according to claim 25, wherein the whiskers have an average diameter of 0.3 μm to 3 μm, and the whiskers have an average length in a range of from 10 times as large as the average diameter to 100 μm.
Claim 35
Dependent Claim
38 words
A prepreg according to claim 25, wherein the whiskers are at least one member selected from the group consisting of aluminum borate whiskers, wollastonite whiskers, potassium titanate whiskers, basic magnesium sulfate whiskers, silicon nitride whiskers and alpha-alumina whiskers.
Claim 36
Dependent Claim
12 words
A prepreg according to claim 25, wherein said prepreg includes said whiskers.
Claim 37
Dependent Claim
13 words
A prepreg according to claim 25, wherein said prepreg includes said short fibers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-10-11 | 2003-04-12 | 2003-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-10-11 | 2007-04-12 | 2007-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-10-11 | 2011-04-12 | 2011-10-12 | $7700.00 | Window Closed / Lapsed |