| 主权项 |
1. A thermochromic yellow ink composition comprising microcapsules containing fatty organic solvents, a developer and a yellow leuco dye that is represented by the following formula: where X1 and X2 can be independently hydrogen, halogen, substituted or non-substituted alkyl, aryl groups, substituted or non-substituted alky ethers or aryl ethers, and mono or bis-alkyl amine or aryl amine, substituted alkyl thio or aryl thio groups; Y can be carbon or nitrogen; Z can be hydrogen, halogen, or other simple alkyl substituents; R, R1 and R2 can be the same or different, they can be independently selected from hydrogen, substituted or non-substituted alkyl or aryl groups, the alky groups can be joined to form a separate ring structures or a fused ring structure with the fluoran skeleton. |
