Toner compositions and process thereof
View Patent ↗A toner composition is provided which contains a polyester resin with hydrophilic groups and hydrophobic end groups and a colorant, wherein said polyester resin is of the formula: wherein R is an alkylene group; X is an aromatic hydrocarbon; Y is selected from the group consisting of an alkali and an alkaline earth metal salt of an arylenesulfonate or an alkylenesulfonate; R′ is a hydrophobic group, and m and n represent the number of random segments of from about 50 to about 300 for n, and from about 20 to about 2,000 for m, and m is less than 20 times n.
1. A toner composition comprised of a polyester resin with hydrophilic groups and hydrophobic end groups and a colorant, wherein said polyester resin is of the formula:
wherein R is an alkylene group;
X is an aromatic hydrocarbon;
Y is selected from the group consisting of an alkali and an alkaline earth metal salt of an arylenesulfonate or an alkylenesulfonate;
R′ is a hydrophobic group, and
m and n represent the number of random segments of from about 50 to about 300 for n, and from about 20 to about 2,000 for m, and m is less than 20 times n.
2. A toner composition in accordance with claim 1 , wherein R′ is derived from a polymeric alcohol.
3. A toner composition in accordance with claim 2 , wherein the polymeric alcohol is from about 10 to about 120 carbon atoms, or from about 20 to about 60 carbon atoms.
4. A toner composition in accordance with claim 1 , wherein said polyester resin is derived from at least one polymeric alcohol moiety of the formula —OH(CH2) p CH 3 , wherein p is a number of from about 10 to about 120, or from about 20 to about 60.
5. A toner composition in accordance with claim 1 , wherein said R′ hydrophobic group is an aliphatic hydrocarbon of from about 10 to about 120 carbon atoms, or from about 20 to about 60 carbons atoms in length.
6. A toner composition in accordance with claim 1 , wherein said R alkylene group contains from about 2 to about 24 carbon atoms and is selected from the group consisting of diethylene, propylene, dipropylene, cycloalkylene, and 1,4-dimethyl cyclohexylene.
7. A toner composition in accordance with claim 1 , wherein said Y comprises from about 3 mole percent to about 8 mole percent of the polyester resin.
8. A toner composition in accordance with claim 1 , wherein said Y arylenesulfonate is phenylenesulfonate.
9. A toner composition in accordance with claim 1 , wherein said X aromatic hydrocarbon is an aryl moiety selected from the group consisting of phenylene, isophthalylene, terephthalylene, and phthalylene.
10. A toner composition in accordance with claim 1 , wherein said metal for said alkali or alkaline earth metal salt is selected from the group consisting of lithium, sodium, potassium, cesium, berylium, magnesium, calcium and barium.
11. A toner composition in accordance with claim 1 , wherein said R′ group comprises from about 0.5% to about 5% parts per weight based on the amount of polyester polymer.
12. A toner composition in accordance with claim 1 , wherein said hydrophilic groups comprise from about 3 weight percent to about 8 weight percent, or from about 4 weight percent to about 6 weight percent of the polyester resin.
13. A toner composition in accordance with claim 1 , further comprising a wax, a charge additive and surface additives.
14. A toner composition in accordance with claim 1 , wherein said polyester resin is of the formula:
wherein R is an alkylene group;
R′ is a hydrophobic group; and
m and n represent the number of random segments of from about 50 to about 300 for n, and from about 20 to about 2,000 for m, and m is less than 20 times n.
15. A toner composition in accordance with claim 14 , further comprising toner particles of an average volume diameter of, from about 3 μm to about 12 μm, or from about 4 μm to about 7 μm.
16. A toner composition in accordance with claim 1 , wherein said R alkylene group contains from about 2 to about 24 carbon atoms and is selected from the group consisting of diethylene, propylene, dipropylene, cycloalkylene, and 1,4-dimethyl cyclohexylene.
17. A toner composition in accordance with claim 1 , wherein R′ hydrophobic group is an aliphatic hydrocarbon of from about 10 to about 120 carbon atoms, or from about 20 to about 60 carbons atoms in length.
18. A toner composition in accordance with claim 1 , wherein said polyester resin is derived from at least one polymeric alcohol of the formula —OH(CH2) p CH 3 , wherein p is a number of from about 10 to about 120, or from about 20 to about 60.
19. A xerographic system comprising a charging component, a photoconductive component, a development component, an image transfer component and a fusing component and wherein the development component contains the toner composition of claim 1 .
20. A process for the preparation of a toner composition comprising:
(a) mixing an emulsion of a polyester resin of the formula
wherein R is an alkylene group;
X is an aromatic hydrocarbon;
Y is an alkali or alkaline earth metal salt of an arylenesulfonate or an alkylenesulfonate and comprises from about 3 mole percent to about 8 mole percent of said polyester resin;
R′ is a hydrophobic group, and
m and n represent the number of random segments of from about 50 to about 300 for n, and from about 20 to about 2,000 for m, or m is less than 20 times n,
with a pigment to form a mixture and heating said mixture at a temperature of from about 50° C. to about 75° C. with stirring;
(b) adding a solution comprising a catalyst to said mixture to form toner particles;
(c) monitoring said toner particle size in said mixture until the volume particle size is less than 25 μm, or from about 3 μm to about 12 μm, with a geometric distribution of about 1.3;
(d) cooling said mixture to a temperature of from about 25° C. to about 30° C., or a temperature of from about 20° C. to about 26° C., and optionally separating said mixture followed by filtration, washing and freeze-drying said toner particles.
21. The process of claim 20 , further comprising adding to said mixture a wax, a charge additive, and/or surface additives to said mixture prior to filtration.
22. The process of claim 20 , wherein said X aromatic hydrocarbon is an arylene moiety selected from the group consisting of phenylene, isophthalylene, terephthalylene, and phthalylene.
23. The process of claim 20 , wherein said metal of said alkali or alkaline earth metal salt of said arylenesulfonate is 5-sulfoisophthalic acid sodium salt.
24. The process of claim 20 , wherein said R′ hydrophobic group is of the formula —(CH2) p CH 3 , wherein p is a number of from about 10 to about 120 or from about 20 to about 60.
25. The process of claim 20 , wherein said R alkylene group contains from about 2 to about 24 carbon atoms.
26. The process of claim 20 , wherein R alkylene group is selected from the group consisting of diethylene, propylene, dipropylene, cycloalkylene, and 1,4-dimethyl cyclohexylene.