John D. Hepworth

Person

Preston, GB

People

Patents Grantslast 30 patents

Information Patent Grant
Grey coloring photochromic fused pyrans
- Patent number 6,387,512
- Issue date May 14, 2002
- James Robinson Limited
- David Allan Clarke
- C07 - ORGANIC CHEMISTRY
Information Patent Grant
Photochromic compounds
- Patent number 6,303,673
- Issue date Oct 16, 2001
- James Robinson Limited
- David A. Clarke
- C07 - ORGANIC CHEMISTRY
Information Patent Grant
Red coloring hyperchromic 3H-naphtho[2,1-B]pyrans
- Patent number 6,294,112
- Issue date Sep 25, 2001
- James Robinson Limited
- David A. Clarke
- C07 - ORGANIC CHEMISTRY
Information Patent Grant
Neutral coloring photochromic 2H-naphtho[1,2-b] pyr...
- Patent number 6,248,264
- Issue date Jun 19, 2001
- James Robinson Limited
- David A. Clarke
- C07 - ORGANIC CHEMISTRY
Information Patent Grant
Photochromic naphthopyran compounds
- Patent number 5,623,005
- Issue date Apr 22, 1997
- Pilkington plc
- Martin Rickwood
- C07 - ORGANIC CHEMISTRY
Information Patent Grant
Photochromic compounds
- Patent number 5,520,853
- Issue date May 28, 1996
- Pilkington plc
- Martin Rickwood
- C07 - ORGANIC CHEMISTRY
Information Patent Grant
Photo reactive spiro-benzoxazine compounds
- Patent number 5,446,151
- Issue date Aug 29, 1995
- Pilkington PLC
- Martin Rickwood
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Photochromic articles
- Patent number 4,913,544
- Issue date Apr 3, 1990
- Pilkington PLC
- Martin Rickwood
- C07 - ORGANIC CHEMISTRY

John D. Hepworth

Person

Patents Grantslast 30 patents

Grey coloring photochromic fused pyrans

Photochromic compounds

Red coloring hyperchromic 3H-naphtho&#x0005B;2,1-B&#x0005D;pyrans

Neutral coloring photochromic 2H-naphtho&#x0005B;1,2-b&#x0005D; pyr...

Photochromic naphthopyran compounds

Photochromic compounds

Photo reactive spiro-benzoxazine compounds

Photochromic articles

Red coloring hyperchromic 3H-naphtho[2,1-B]pyrans

Neutral coloring photochromic 2H-naphtho[1,2-b] pyr...