Diarylethene derivatives and photochromic thin film prepared using the same

The present invention provides a photochromic diarylethene derivative expressed by the following formula (1),

• 7
• wherein R1 is alkylene, or fluoro-substituted alkylene;
• a is an integer of 0˜3, Ar1 and Ar2 are independently a compound of formula (2) or a compound of formula (3);
• Z is fluoro-substituted or non-substituted methylene, carbonyl or CN when Z and Z is not linked by R′(a=0);
• 8
• wherein R2 and R5 are fluoro-substituted or non-substituted C1-C3 alkyl;
• R3 is the same as R2 and R5, a hydrogen atom, or a fluoro atom;
• Both or one of R4 and R6 are independently acetyl, phenylisoxazole, hydroxymethylisoxazole, alkyleneoxyalkyl ester, aldehyde, carboxylic acid, —[CH═CH]l—[C(═O)]m[CH2]n—[CH═CH]o—C(R7)p(R8)q, or —C≡C—R9, and one of R4 and R6 is the same as R3 when one of R4 and R6 are the group described above;
• R7, R8, and R9 are independently a hydrogen atom, C1-C22 alkyl or phenyl;
• l, n, and o are independently an integer of 0 to 10;
• m is 0 or 1;
• p and q are independently an integer of 0 to 3, and p+q=3;
• X and Y are independently an oxygen, nitrogen or sulfur atom.