| abstract |
A compound that changes color by irradiation and has the following general structural formula. X—C≡C—C≡C—Y— (CO) n -QZ Wherein X is H, alkyl or -Y- (CO) n- QW; each Y is the same or different divalent alkylene group; Q is O, S or NR; R is H Or is alkyl; W is H, alkyl or Z; each Z is the same or different unsaturated alkyl group; and each n is 0 or 1] |