Formaldehyde-free inkjet compositions and processes
Disclosed are a process for inkjet printing color images on various substrates using a formaldehyde-free crosslinking agent in the ink composition, which is therefore devoid of formaldehyde emission and suitable for health-aware manufacturing practices, as well as objects having images and designs printed thereon which are devoid of formaldehyde and therefore suitable for use by infants.
1. An inkjet composition comprising a crosslinking agent, a property-sensitive agent, a co-polymerizable agent, a colorant and a second carrier, said property-sensitive agent is sensitive to a change in a chemical and/or physical property, such that upon effecting said change on a surface of an object the inkjet composition congeals on said surface to thereby form an image on said object, wherein said crosslinking agent is a formaldehyde-free crosslinking agent and said image is substantially devoid of formaldehyde emission, said formaldehyde-free crosslinking agent is a heteroaryl polycarbamate.
2. The composition of claim 1 , being substantially devoid of formaldehyde emission.
3. The composition of claim 1 , wherein a formaldehyde level emitted thereby is equal or less than 20 ppm, subsequent to printing and curing said image.
4. The composition of claim 1 , wherein said object is a garment.
5. The composition of claim 1 , wherein said object is intended for use by infants.
6. The composition of claim 1 , wherein said heteroaryl polycarbamate is a tris(alkoxycarbonylamino) triazine.
7. The composition of claim 1 , wherein said property is acidity and said change is effected by an acid.
8. The composition of claim 7 , wherein said acid is a transitory acid.
9. The composition of claim 8 , wherein said transitory acid is a volatile acid and/or an intra/cross-reactive acid.
10. The composition of claim 9 , wherein said transitory acid is selected from the group consisting of an α-hydroxy acid, glycolic acid, lactic acid, carbonic acid, formic acid, acetic acid, propionic acid and butanoic acid.
11. The composition of claim 1 , forming a part of a multi-part ink composition.
12. The composition of claim 11 , wherein said multi-part ink composition further comprises an immobilization composition.
13. The composition of claim 12 , wherein said multi-part ink composition further comprises a third part which comprises said emulsified property-sensitive agent, a dispersed metal oxide, a third carrier, said co-polymerizable agent and said formaldehyde-free crosslinking agent, whereas said third part congeals when converging with said immobilization composition on said surface.
14. The composition of claim 13 , wherein said third carrier is an aqueous carrier.
15. The composition of claim 13 , wherein said metal oxide is substantially opaque white and selected from the group consisting of titanium dioxide, lead oxide, zinc oxide and molybdenum oxide.
16. The composition of claim 1 , wherein said ink composition further comprises a co-polymerizable binder, a polymerization catalyst, a buffering agent, a softener/plasticizer, a surface active agent, a surface tension modifying agent, a viscosity modifying agent, a thickener agent, an anticorrosion agent and any combination thereof.
17. The composition of claim 1 , wherein said second carrier is an aqueous carrier.
18. The composition of claim 1 , wherein said immobilization further comprises a first carrier, said first carrier is an aqueous carrier.
19. An object having an image printed thereon, the image is printed by the composition of claim 1 .
20. The object of claim 19 , wherein a formaldehyde level exhibited thereby is equal or less than 20 ppm.