Inventor · disambiguated record
John David Hepworth
Also filed as: HEPWORTH JOHN D · HEPWORTH JOHN DAVID
8 granted patents·348 citations·filing 1987–1999
90Inventor score
Top patents by PatentIndex Score
8 records- 0197US4913544APhotochromic articlesPILKINGTON PLC·Filed 1987·Granted Apr 3, 1990·154 cites·63 claims
- 0288US5623005APhotochromic naphthopyran compoundsPILKINGTON PLC·Filed 1994·Granted Apr 22, 1997·49 cites·23 claims
- 0388US5446151APhoto reactive spiro-benzoxazine compoundsPILKINGTON PLC·Filed 1993·Granted Aug 29, 1995·20 cites·18 claims
- 0487US6303673B1Photochromic compoundsJAMES ROBINSON LTD·Filed 1998·Granted Oct 16, 2001·19 cites·23 claims
- 0586US6248264B1Neutral coloring photochromic 2H-naphtho[1,2-b] pyrans and heterocyclic pyransJAMES ROBINSON LTD·Filed 1998·Granted Jun 19, 2001·50 cites·10 claims
- 0682US5520853APhotochromic compoundsPILKINGTON PLC·Filed 1994·Granted May 28, 1996·26 cites·14 claims
- 0774US6294112B1Red coloring hyperchromic 3H-naphtho[2,1-B]pyransJAMES ROBINSON LTD·Filed 1998·Granted Sep 25, 2001·22 cites·20 claims
- 0857US6387512B1Grey coloring photochromic fused pyransJAMES ROBINSON LTD·Filed 1999·Granted May 14, 2002·8 cites·15 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →