Nanosized particles of benzimidazolone pigments
View Patent ↗A nanoscale pigment particle composition includes an organic benzimidazolone pigment, and a sterically bulky stabilizer compound, wherein the benzimidazolone pigment associates non-covalently with the sterically bulky stabilizer compound that is a substituted pyridine derivative; and the presence of the associated stabilizer limits the extent of particle growth and aggregation, to afford nanoscale pigment particles.
1. A nanoscale pigment particle composition, comprising:
a benzimidazolone pigment, and
a sterically bulky stabilizer compound associated non-covalently with the benzimidazolone pigment, wherein the sterically bulky stabilizer compound comprises a substituted pyridine derivative;
wherein presence of the sterically bulky stabilizer limits an extent of particle growth and aggregation, to afford nanoscale pigment particles.
2. The composition of claim 1 , wherein the nanoscale pigment particles have an average particle diameter as derived from transmission electron microscopy imaging, of less than about 150 nm.
3. The composition of claim 1 , wherein the benzimidazolone pigment comprises a diazo component group and a nucleophilic coupling component group that are linked together with at least one azo group, wherein at least one of the diazo component group and the nucleophilic coupling component group comprises a benzimidazolone moiety.
4. The composition of claim 3 , wherein the diazo component group is selected from the group consisting of DC 1 to DC 7 :
wherein:
* denotes a point of attachment to an amino group (—NH 2 ) in the diazo component precursor and a point of attachment to an azo group (—N═N—) in the benzimidazolone pigment,
R 1 to R 8 independently represent H; halogens; (CH 2 ) n CH 3 where n=0-6; OH; alkoxyl groups —OR′ where R′ represents H, (CH 2 ) n CH 3 , or C 6 H 5 , and n represents a number of from 1 to about 6; CO 2 H; CO 2 CH 3 ; CO 2 (CH 2 ) n CH 3 wherein n=0-5; CONH 2 ; (CO)R′ wherein R′ can independently represent H, C 6 H 5 , (CH 2 ) n CH 3 wherein n=0-12, or (CH 2 ) n N(CH 3 ) 2 wherein n=1-6; OCH 3 ; OCH 2 CH 2 OH; NO 2 ; SO 3 H; or any of the following structural groups:
in DC 2 and DC 3 R′ represents H, (CH 2 ) n CH 3 , or C 6 H 5 , and n represents a number of from 1 to about 6, and
group A represents —(CH 2 ) n — where n=0-6; —[O—(CH 2 ) n —O]— where n=0-6; —[O—CH 2 CHR) n ]— where n=0-6 and R═H or CH 3 ; —(C═O)—; O; S; —(CH 2 ) n —(C═O)— where n=1-6; and —(C═O)—(CH 2 ) n —(C═O)— where n=1-6.
5. The composition of claim 3 , wherein the nucleophilic coupling component group is selected from the group consisting of:
wherein R 9 , R 10 , R 11 , R 12 , and R 13 all independently represent H, Br, Cl, I, F, CH 3 , or OCH 3 , and * denotes a point of attachment to the azo group in the pigment.
6. The composition of claim 1 , wherein the sterically bulky stabilizer is associated with the benzimidazolone pigment predominantly by at least one of intra-molecular and inter-molecular hydrogen bonding, aromatic pi-stacking, and van der Waals forces.
7. The composition of claim 1 , wherein the sterically bulky stabilizer is a compound of the formula:
wherein R 1 to R 5 can be the same or different and represent H, —NH—(C═O)—R′, —(C═O)—NH—R′,), —NH—R′, —NH—(C═O)—NH—R′, —NH—(C═O)—O—R′, O—(C═O)—NH—R′, —O—(C═O)—R′, branched or linear alkyleneoxy chains, or —OR′, wherein R′ is predominantly a linear or branched alkyl or cycloaliphatic group that may contain heteroatoms within the alkyl groups.
8. The composition of claim 7 , wherein three of R 1 to R 5 each represent H.
9. The composition of claim 7 , wherein R 2 , R 3 and R 4 each represent H.
10. The composition of claim 7 , wherein four of R 1 to R 5 each represent H.
11. The composition of claim 1 , wherein the sterically bulky stabilizer is a compound of the formula:
where X represents —N(H)— or —O—, and R 1 and R 2 independently represent a linear or branched alkyl or cycloaliphatic group, and which may contain heteroatoms.
12. The composition of claim 11 , wherein R 1 and R 2 are selected from the group consisting of:
wherein m and n independently represent an integer of 0 to about 30.
13. The composition of claim 11 , wherein R 1 and R 2 are the same.
14. The composition of claim 11 , wherein R 1 and R 2 are different.
15. The composition of claim 1 , wherein the sterically bulky stabilizer compound comprises two or more pyridine groups.
16. The composition of claim 1 , wherein the sterically bulky stabilizer is a compound of the formula:
R 1 to R 4 can be the same or different and represent H, —NH—(C═O)—R′, —(C═O)—NH—R′), —NH—R′, —NH—(C═O)—NH—R′, —NH—(C═O)—O—R′, O—(C═O)—NH—R′, —(C═O)—O—R′, —O—(C═O)—R′, branched or linear alkyleneoxy chains, or —OR′, wherein R′ is predominantly a linear or branched alkyl or cycloaliphatic group that may contain heteroatoms within the alkyl groups, and R y represents a bridging group.
17. The composition of claim 16 , wherein R y represents a group selected from the group consisting of —(CH 2 ) n , —X—(CH 2 ) n X, —[(XCH 2 CH 2 ) n ]X—, —[(C═O)—(CH 2 ) n —(C═O)]—, —X—[(C═O)—(CH 2 ) n —(C═O)]—X—, —X—[(C═O)—X—(CH 2 ) n —X—(C═O)]—X—, —[(C═O)—X—(CH 2 ) n —X—(C═O)]—,
wherein X, X 1 , and X 2 independently represent O, S, or NH, and n is an integer of 1 to 50.
18. The composition of claim 1 , wherein the sterically bulky stabilizer compound comprises a substituted pyridine derivative selected from the group consisting of the following compounds:
R 1
R 2
R 3
R 4
R 5
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
19. The composition of claim 1 , wherein the sterically bulky stabilizer compound comprises a substituted pyridine derivative selected from the group consisting of the following compounds:
Groups X
R 1 = R 2 = R 3
R y
X 1 = X 2 = NH
H
X 1 = O X 2 = NH
H
X 1 = NH
H
X 1 = O
H
X 1 = O
H
X 1 = NH
H
20. The composition of claim 1 , further comprising a surfactant or surface active agent selected from the group consisting of derivatives of rosin natural products; long-chain or branched hydrocarbon alcohols; alcohol ethoxylates; acrylic-based polymers; styrene-based copolymers; copolymers of α-olefins; copolymers of vinyl pyridine, vinyl imidazole, and vinyl pyrrolidinone; polyester copolymers; polyamide copolymers; and copolymers of acetals and acetates.
21. The composition of claim 1 , wherein the nanoscale pigment particles have an aspect ratio of 1:1 to about 7:1.
22. The composition of claim 1 , wherein the nanoscale pigment particles have a shape selected from the group consisting of rods, platelets, needles, prisms, and substantially spherical.
23. A marking material composition comprising the nanoscale pigment particle composition of claim 1 , wherein the marking material composition is an ink composition or a toner composition.
24. An electrophotographic photoreceptor comprising the nanoscale pigment particle composition of claim 1 .
25. A solar cell comprising an organic photo conducting material comprising the nanoscale pigment particle composition of claim 1 .
26. A biological or chemical sensor comprising the nanoscale pigment particle composition of claim 1 .