Dyes and use thereof in thermal imaging members and methods
View Patent ↗There are described novel fluorescein dye compounds and imaging members and imaging methods utilizing the compounds. The fluorescein dye compounds exhibit a first color when in the crystalline form and a second color, different from the first color, when in the liquid, amorphous form.
1. A compound represented by the formula
wherein:
R 1 , R 2 , R 5 , R 6 , R 8 , R 9 and R 10 are each independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, heterocycloalkyl, substituted heterocycloalkyl, substituted carbonyl, acylamino, halogen, nitro, nitrilo, sulfonyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, oxygen, substituted oxygen, nitrogen, substituted nitrogen, sulfur and substituted sulfur;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl having from 1 to 3 carbon atoms, substituted alkyl having from 1 to 3 carbon atoms, alkenyl having from 1 to 3 carbon atoms, substituted alkenyl having from 1 to 3 carbon atoms, alkynyl having from 1 to 3 carbon atoms, substituted alkynyl having from 1 to 3 carbon atoms, substituted oxygen, substituted nitrogen, and substituted sulfur;
R 7 is absent or selected from the group consisting of hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, heterocycloalkyl substituted heterocycloalkyl substituted carbonyl, acylamino, halogen, nitro, nitrilo, sulfonyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, oxygen, substituted oxygen, nitrogen, substituted nitrogen, sulfur and substituted sulfur;
R 11 is selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, heterocycloalkyl, substituted heterocycloalkyl, substituted carbonyl, acylamino, sulfonyl, aryl, substituted aryl, heteroaryl and substituted heteroaryl; and
X 1 is carbon or nitrogen;
provided that at least one of R 1 , R 2 , R 5 and R 6 is selected from the group consisting of alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, heterocycloalkyl, substituted heterocycloalkyl, aryl, substituted aryl, heteroaryl and substituted heteroaryl.
2. A compound according to claim 1 wherein X 1 is carbon, R 7 , R 8 , R 9 and R 10 are each hydrogen and R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 11 are as defined in claim 1 .
3. A compound according to claim 1 wherein R 11 is alkyl or substituted alkyl and two of R 1 , R 2 , R 5 and R 6 are alkyl or substituted alkyl having between one and twelve carbon atoms and X 1 is carbon.
4. A compound according to claim 1 wherein R 1 , R 3 , R 4 , R 6 , R 7 , R 8 , R 9 and R 10 are each hydrogen, R 2 and R 5 are each alkyl having 6 carbon atoms, R 11 is ethyl and X 1 is carbon.
5. A compound according to claim 1 wherein R 1 , R 3 , R 4 , R 6 , R 7 , R 8 , R 9 and R 10 are each hydrogen, R 2 and R 5 are each alkyl having 3 carbon atoms, R 11 is benzyl and X is carbon.
6. A compound according to claim 1 wherein R 1 , R 3 , R 4 , R 6 , R 7 , R 8 , R 9 and R 10 are each hydrogen, R 2 and R 5 are each benzyl, R 11 is —CH 2 CH 2 CH(CH 3 ) 2 , and X 1 is carbon.
7. A color imaging member comprising a first image-forming layer including a compound according to claim 1 , said compound being in the crystalline form.
8. The imaging member as defined in claim 7 and further including a substrate and at least a second color-forming layer, said second color-forming layer being capable of forming a color different from that formed by said first color-forming layer.
9. The imaging member as defined in claim 8 and further including a third color-forming layer, said third color-forming layer being capable of forming a color different from those formed by said first and second color-forming layers.
10. The imaging member as defined in claim 9 wherein said color-forming layers form magenta, cyan and yellow color, respectively.
11. An imaging method comprising
(a) providing an imaging member as defined in claim 7 ; and
(b) converting at least a portion of said compound to the liquid form in an imagewise pattern whereby an image is formed.
12. The method as defined in claim 11 wherein step(b) comprises applying an imagewise pattern of thermal energy to said imaging member whereby at least a portion of said compound is converted to the liquid form and an image is formed.
13. The imaging method as defined in claim 12 wherein said imaging member further includes a substrate and at least a second color-forming layer, said second color-forming layer being capable of forming a color different from that formed by said first color-forming layer.
14. The imaging method as defined in claim 13 wherein said imaging member further includes a third color-forming layer, said third color-forming layer being capable of forming a color different from those formed by said first and second color-forming layers.
15. The imaging method as defined in claim 14 wherein said color-forming layers form magenta, cyan and yellow color, respectively.
16. The imaging member as defined in claim 7 wherein said compound has a melting point of from about 60° C. to about 300° C.
17. The imaging method as defined in claim 11 wherein said compound has a melting point of from about 60° C. to about 300° C.