Invalidity dossier
US 5157418
Ink jet recording head with through-hole wiring connector
Current assignee: Canon Inc
Added 9/23/2026, 9:33:22 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,157,418
Title: Ink jet recording head with through-hole wiring connector
Patent number: US 5,157,418 A
Application number: US 07/668,686
Inventor: Hideo Tamura
Assignee: Canon Inc. (listed; Google notes assignee listings may be inaccurate)
Priority date: 1988-06-03 (noted as an assumption, not a legal conclusion)
Filing date: 1991-03-07
Publication/grant date: 1992-10-20
Legal status: Expired – Lifetime; anticipated expiration 2009-10-20
Purpose: The invention addresses problems in conventional liquid emission (ink jet) recording heads, where a common electrode member was adhered to the substrate and connected to the common electrode wiring by wire bonding. The number of wire bonds corresponded to the number of discharge openings, making the process complex, precision-demanding, and prone to wire disconnection, and requiring a cumbersome common electrode member matched to the recording head width. An object is a recording head produced by a very simple, low-cost process that still offers high precision and reliability in electrical connections.
Plain-language scope: A substrate for a liquid emission recording head comprises a support member; multiple electrothermal converting elements, each having a heat-generating resistor layer, a common electrode wiring layer, and an individual electrode wiring layer both connected to the resistor layer, plus a protective layer; an insulating layer on the common electrode wiring layer; and a common electrode connected in common to the plural common electrode wiring layers across that insulating layer by through-holes provided in it. Liquid paths are formed on the substrate over the heat-generating areas between the common and individual electrode wiring layers, with discharge openings communicating with the paths; thermal energy generated in the heat-generating areas emits the liquid. A recording apparatus includes the head and switch means of a power source for driving it.
Source: https://patents.google.com/patent/US5157418/en
What the excerpt does not establish: The excerpt is partial and omits text after FIG. 4. It does not provide the full claims, complete description, drawings, or prosecution history; does not establish enforceability, ownership transfers, or validity; and does not substantiate prior-art comparisons. Dates marked as assumptions are not verified legal conclusions.
Generated 10/1/2026, 9:34:13 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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