Issued Patents All Time
Showing 26–50 of 59 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6703526 | Coupler for use in oxidative hair dyeing | Yuh-Guo Pan, Margaret Popp | 2004-03-09 |
| 6673932 | Primary intermediates for oxidative coloration of hair | Yuh-Guo Pan | 2004-01-06 |
| 6673934 | Primary intermediates for oxidative coloration of hair | Yuh-Guo Pan | 2004-01-06 |
| 6673966 | Coupler for use in oxidative hair dyeing | Yuh-Guo Pan, James S. Anderson | 2004-01-06 |
| 6572665 | Coupler for use in oxidative hair dyeing | Yuh-Guo Pan, Margaret Popp | 2003-06-03 |
| 6521761 | Primary intermediates for oxidative coloration of hair | Yuh-Guo Pan | 2003-02-18 |
| 6409773 | Coupler for use in oxidative hair dyeing | Yuh-Guo Pan, Margaret Popp | 2002-06-25 |
| 6342079 | Primary intermediate for use in oxidative hair dyeing | Yuh-Guo Pan, Linas R. Stasaitis | 2002-01-29 |
| 6228130 | Primary intermediate in oxidative hair dyeing | Linas R. Stasaitis, Yuh-Guo Pan, Michael Wong | 2001-05-08 |
| 6200353 | Coupler for use in oxidative hair dyeing | Linas R. Stasaitis, Yuh-Guo Pan | 2001-03-13 |
| 6074438 | Hair dyeing compositions containing 2-chloro- and 2,6-dichloro-4-aminophenol and phenylpyrazolones | Yuh-Guo Pan, Linas R. Stasaitis | 2000-06-13 |
| 6045590 | Storage stable 2-methyl-1-naphthol couplers | Yuh-Guo Pan, Linas R. Stasaitis, John D. O'Donoghue | 2000-04-04 |
| 5993491 | Oxidative hair dye compositions and methods containing 1-(4-aminophenyl)-2-pyrrolidinemethanols | Margaret Popp, Yuh-Guo Pan | 1999-11-30 |
| 5961666 | Hair dye compositions containing 3-substituted-4-aminophenols and 2-substituted-1-naphthols | Yuh-Guo Pan, James S. Anderson | 1999-10-05 |
| 5891200 | Hair dye compositions containing anthraquinone dyes having a quaternary ammonium side chain and neutral direct dyes | Linas R. Stasaitis, Yuo-Guo Pan | 1999-04-06 |
| 5876464 | Hair dyeing with N-(4-aminophenyl) prolineamide, couplers, and oxidizing agents | Margaret Popp, Yuh-Guo Pan | 1999-03-02 |
| 5849042 | Hair dye compositions containing 2,3 dialkyl-4-aminophenol and a 2-alkyl-1-naphthol | Yuh-Guo Pan | 1998-12-15 |
| 5672180 | Storage stable 2-methyl-1-naphthol couplers | Yuh-Guo Pan, Linas R. Stasaitis, John D. O'Donoghue | 1997-09-30 |
| 5670698 | Synthesis of 1-acetoxy-2-methylnaphthalene | Yuh-Guo Pan, Linas R. Stasaitis, James S. Anderson | 1997-09-23 |
| 5529583 | Storage stable 2-methyl-1-naphthol couplers | Yuh-Guo Pan, Linas R. Stasaitis, John D. O'Donoghue | 1996-06-25 |
| 5520707 | Methods for dyeing hair with anthraquinone hair dyes having a quaternary ammonium side chain | Linas R. Stasaitis, Yuo-Guo Pan | 1996-05-28 |
| 5486619 | Method of producing DAI from DOPA, using one reaction vessel | Gottfried Wenke, Yuh-Guo Pan, Linas R. Stasaitis | 1996-01-23 |
| 5474578 | Erasable hair dyeing process | Alexander Chan, Alice Mayer, Jia-Shen Wang, Gottfried Wenke | 1995-12-12 |
| 5420362 | Synthesis of 2-methyl-1-naphthol | Linas R. Stasaitis, Yuo-Guo Pan, Alexander Chan | 1995-05-30 |
| 5344463 | Hair dye compositions and methods utilizing 2-substituted-1-naphthol couplers | Alexander Chan, Yuh-Guo Pan, Richard DeMarco | 1994-09-06 |