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Method for rapid manufacture of nitrided thick layer of super high hardness on ferrous metal articles

US 3,639,641 A · Inventors: SATOH SHINZOH

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

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Why it's free to use

  • Granted February 1, 1972. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by February 1, 1989.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledMarch 20, 1969
GrantedFebruary 1, 1972
Term endedFebruary 1, 1989
Application number—
Classification (CPC)B01J21/06 +2 more
Length2 pages

Timeline

Timeline From USPTO dates

1970197219741976197819801982198419861988Application filedMarch 20, 1969Patent grantedFeb 1, 1972Term endedFeb 1, 1989

Sources & verification

Official USPTO records

Full published documentText and every drawing sheet as a PDF.USPTOFile historyStatus, office actions, notices, fee records and petitions.USPTO Patent CenterPatent Public Search recordSearchable full text and bibliographic data.USPTO

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