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System for the continuous and automatic measurement of the sulfur content of petroleum fractions

US 3,500,446 A · Inventors: HASEGAWA KEISHI et al.

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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 March 10, 1970. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by March 10, 1987.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledFebruary 14, 1968
GrantedMarch 10, 1970
Term endedMarch 10, 1987
Application number—
Classification (CPC)G01N23/12 +1 more
Length4 pages

Timeline

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1969197119731975197719791981198319851987Application filedFeb 14, 1968Patent grantedMarch 10, 1970Term endedMarch 10, 1987

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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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