| 摘要 |
NEW MATERIAL:A pentadiene compound of formula I (wherein R<1>, R<2>, R<3> and R<4> are each a lower alkyl; and R<5> is an aryl or naphthyl which may be substituted with a halogen, an alkyl or an alkoxy). EXAMPLE:1,5-bis[4-(N,N-dimethylamino)phenyl]-5-phenylsulfonyl-penta-1, 3-diene. USE:A color former which has a strong absorption in the near-infrared region in a colored state, can be used in, for example, the production of thermal recording materials and can develop a high-density and clear color. PREPARATION:A benzaldehyde derivative of formula II is condensed with another benzaldehyde derivative of formula II through dehydration to produce a compound of formula IV, which is reduced into a compound of formula V and reacted with perchloric acid to form a compound of formula VI, which is reacted with an alkali metal salt of a sulfinic acid to obtain a compound of formula I. |
