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US3421887A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing a magnesium-containing spherical graphite cast iron having little dross present

Assignee: Kusaka Rare Metal Products Co Ltd
•
Filing: 1967-05-29
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Granted: 1969-01-14
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Expires: 1987-05-29
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Abstract

No abstract record available.

Inventors

  • 👤 Kazuji Kusaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 05:42
CPC Classifications
C; C22; C22C; C22C37/00; C22C37/04; C21; C21C; C21C1/00; C21C1/10; C21C7/00; C22C35/00

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US2622022A Cited
US2750284A Cited
US2948605A Cited
US2814559A Cited
US2821473A Cited
US2822266A Cited
US2932567A Cited
US2922713A Cited
US2980530A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1972-01-14 1972-07-15 1973-01-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1976-01-14 1976-07-15 1977-01-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1980-01-14 1980-07-15 1981-01-14 $7700.00 Window Closed / Lapsed

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