Onodera, Akira et al. published their patent in 1997 |CAS: 28489-43-2

The Article related to azomethine dye jet printing ink, pyrazolotriazole azomethine dye, aminopyridine azomethine dye, Dyes, Organic Pigments, Fluorescent Brighteners, and Photographic Sensitizers: Azo Dyes and Pigments and other aspects.Computed Properties of 28489-43-2

On April 23, 1997, Onodera, Akira; Ninomiya, Hidetaka; Ohya, Hidenobu; Ishibashi, Daisuke; Komamura, Tawara; Katoh, Katsunori; Tanaka, Tatsuo; Morimoto, Hitoshi published a patent.Computed Properties of 28489-43-2 The title of the patent was Azomethine dyes and their use in ink-jet recording inks. And the patent contained the following:

A recording method comprises the step of ejecting an ink-jet recording ink on a receptor using an ink-jet printer, the ink comprising a dye represented by the formula I [R1, R2 = H, halogen, NH2, organic group; X = OH, NR3R4; R3, R4 = H, hydrocarbyl, heterocyclyl, or R1R3 or R3R4 form a ring; Y1, Y2 = N, CR; R = H, alkyl, acylamino; Y1 or Y2 = N; Z completes an (un)substituted 5- or 6-membered ring, which may bear another condensed ring; R2 or a substituent on Z has Hammett σp -0.3 to +1.0]. Thus, II was prepared in a 9-step synthesis from 6-methyl-2-pyridinamine and 5-tert-butyl-2-hydrazino-6H-1,3,4-thiadiazine. An ink with good color tone and storage stability was prepared from a I 3, H(OCH2CH2)2OH 10, Bu(OCH2CH2)3OH 7, PrOH 3, and H2O 77%. The experimental process involved the reaction of N,N-DIethyl-6-methyl-5-nitro-2-pyridinamine(cas: 28489-43-2).Computed Properties of 28489-43-2

The Article related to azomethine dye jet printing ink, pyrazolotriazole azomethine dye, aminopyridine azomethine dye, Dyes, Organic Pigments, Fluorescent Brighteners, and Photographic Sensitizers: Azo Dyes and Pigments and other aspects.Computed Properties of 28489-43-2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem