Continuous coalescence process for sustainable toner
A continuous coalescence process for preparing a sustainable toner is described which features toner with lowered melt properties and higher toner surface carbon to oxygen (C/O) ratios than previously described sustainable resins coalesced in a batch reactor.
1. A continuous coalescence process for making a sustainable toner comprising the step of continuously coalescing toner particles, wherein the toner particles comprise at least one bio-based resin, comprising a coalescence time of from about 30 seconds to about 10 minutes at a temperature of at least about 80° C. to produce sustainable toner, wherein said sustainable toner optionally comprises a crystalline polyester (CPE) resin, a gel or both.
2. The process of claim 1 , wherein coalescing comprises coalescing at a temperature of from about 80° C. to about 95° C.
3. The process of claim 1 , where coalescing comprises coalescing at a pH from about 7 to about 9.
4. The process of claim 1 , wherein coalescing occurs in a single continuous reactor.
5. The process of claim 1 , wherein coalescing occurs in plural continuous reactors.
6. The process of claim 1 , wherein said toner particles are made in a batch reactor.
7. The process of claim 1 , wherein said toner particles are made in a continuous reactor.
8. The process of claim 1 , comprising a residence time of from about 40 seconds to about 7 minutes.
9. The process of claim 1 , wherein said sustainable toner comprises coalesced particles having a median diameter (D 50 ) of from about 3.5 μm to about 8 μm.
10. The process of claim 1 , wherein said sustainable toner comprises particles comprising a surface C/O ratio of about 4 or higher.
11. The process of claim 1 , wherein the sustainable toner comprises a crystalline polyester resin present in an amount of 4 weight percent or less.
12. The process of claim 1 , wherein the sustainable toner is free of crystalline polyester resin.
13. The process of claim 1 , wherein said sustainable toner comprises 0% gel.
14. The process of claim 1 , comprising prior to coalescing, increasing temperature of said toner particles in a first portion of a reactor.
15. The process of claim 1 , optionally comprising a second portion of a reactor for coalescing said toner particles.
16. The process of claim 1 , comprising subsequent to coalescing, decreasing temperature of said toner particles in a third portion of a reactor.
17. The process of claim 1 , further comprising quenching coalescence in an ice water bath.
18. The process of claim 1 , wherein said toner particles comprise a polyester resin.
19. The process of claim 1 , wherein said sustainable toner is at least about 50% biodegradable.
20. The process of claim 1 , wherein said sustainable toner comprises a wax, a colorant or both.