EP0143660A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Resistors, methods of forming said resistors, and articles comprising said resistors
Assignee: Electro Materials Corp of America
•
Filing: 1984-11-29
•
Granted: —
•
Expires: 2004-11-29
Abstract
Abstract This invention concerns resistor compositions, methods of forming such resistor compositions, and articles comprising a substrate carrying such resistor compositions. The resistor compositions of the invention comprise carbon particles embedded in a matrix formed from short chain-length phenolic resin, long chain-length phenolic resin, epoxy and, optionally filler. The resistor compositions of the invention can be formed by mixing short chain-length phenolic resin, long chain-length phenolic resin, solvent, and, if present, filler with carbon particles to form a solution which is then mixed with the epoxy to form an ink. The ink is applied to a substrate to form a film thereon which is cured to evaporate solvent and to allow polymerization to occur thereby leaving the resistor composition on the substrate.
Inventors
- 👤 Frank Wayne Martin
- 👤 Samson Shahbazi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 02:07
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/0652; H01C17/06573; H01C17/06586
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
26 words
A resistor composition comprising carbon particles embedded in a matrix comprising polymer containing units derived from short chain-length phenolic resin, long chain-length phenolic resin and epoxy.
Claim 2
Dependent Claim
26 words
A resistor composition comprising carbon particles embedded in a matrix comprising polymer containing units derived from short chain-length phenolic resin, long chain-length phenolic resin and epoxy.
Claim 3
Dependent Claim
16 words
A composition as claimed in claim 1, in which said epoxy is a moderate chain-length epoxy.
Claim 4
Dependent Claim
24 words
A composition as claimed in Claim 1 or 2, in which said carbon particles are formed from high structure carbon and low structure carbon.
Claim 5
Dependent Claim
23 words
A composition as claimed in Claim 1 or 2, in which said carbon particles are formed from high structure carbon and acetylene black.
Claim 6
Dependent Claim
22 words
A composition as claimed in Claim 1 or 2, in which said carbon particles are formed from graphite and high structure carbon.
Claim 7
Dependent Claim
19 words
A resistor composition as claimed in any of claims 1 to 5, in which the matrix also comprises filler.
Claim 8
Dependent Claim
17 words
A composition as claimed in Claim 6, in which said filler comprises boron nitride and zinc oxide.
Claim 9
Dependent Claim
15 words
A composition as claimed in Claim 6, in which said filler comprises metallic silver particles.
Claim 10
Independent Claim
83 words
A method of forming a resistor composition as claimed in any of claims 1 to 8 comprising the steps of mixing solvent, short chain-length phenolic resin, long chain-length phenolic resin and, optionally, filler with carbon particles to form a solution, permitting said solution to cool, mixing said solution with epoxy to form an ink, applying said ink to a substrate to form a film therein, applying heat to said film to evaporate said solvent to leave a resistor composition film on said substrate.
Claim 11
Dependent Claim
64 words
A method as claimed in claim 9, in which said short chain-length phenolic resin makes up 50 to 60% by weight of said ink, said long chain-length phenolic resin makes up 8 to 15% by weight of said ink, said epoxy makes up 10 to 20% by weight of said ink and said solvent makes up 2 to 10% by weight of said ink.
Claim 12
Dependent Claim
43 words
A method as claimed in claim 10, in which said carbon particles are formed from graphite and high structure carbon, said graphite making up 10 to 20% by weight of said ink and said high structure carbon making up 1 to 4% by
Claim 13
Dependent Claim
32 words
A method as in claim 11, in which filler is present and comprises metallic silver particles, said metallic silver particles making up approximately 20% by weight of said ink.weight of said ink.
Claim 14
Dependent Claim
51 words
A method as claimed in claim 10 in which said carbon particles are formed from high structure carbon and low structure carbon, said high structure carbon making up 1 to 4% by weight of said ink and said low structure carbon making up 10 to 15% by weight of said ink.
Claim 15
Dependent Claim
49 words
A method as claimed in claim 10 in which said carbon particles are formed from high structure carbon and acetylene black, said high structure carbon making up 1 to 4% by weight of said ink and said acetylene black making up 8 to 15% by weight of said ink.
Claim 16
Dependent Claim
46 words
A method as claimed in claim 13 or 14, in which said filler comprises boron nitride and zinc oxide, said boron nitride making up 3.5 to 10% by weight of said ink and said zinc oxide making up 1 to 5% by weight of said ink.
Claim 17
Dependent Claim
18 words
An article comprising a substrate carrying a resistor composition as claimed in any of claims 1 to 8.
Claim 18
Dependent Claim
14 words
An article as in claim 16, in which said substrate comprises a circuit board.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.