FUSING AGENTS WITH TRIAZINE RADIATION ABSORBERS FOR THREE-DIMENSIONAL PRINTING

1 . A fusing agent for three-dimensional printing, comprising:

from about 0.5 wt % to about 6 wt % triazine radiation absorber;

from about 40 wt % to about 90 wt % organic cosolvent;

from about 0.4 wt % to about 4 wt % of a surfactant selected from a polyethylene sorbitol ester, a polyoxyethylene lauryl ether, or a mixture thereof; and

water.

2 . The fusing agent of claim 1 , wherein the polyethylene sorbitol ester is present and is polyoxyethylene-sorbitan-20 mono-oleate.

3 . The fusing agent of claim 1 , wherein the polyethylene sorbitol ester is present and is polyethylene(23)lauryl ether.

4 . The fusing agent of claim 1 , wherein the fusing agent exhibits an absorbance from about 0.3 to 2 at a wavelength from about 340 nm to about 400 nm.

5 . The fusing agent of claim 1 , wherein the triazine radiation absorber is a triazine derivative compound selected from 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-isooctyloxyphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethyl phenyl)-6-(2-hydroxy-4-methoxy phenyl)1,3,5-triazine, 2-(2-hydroxy-4-hexyloxyphenyl)-4,6-bis(phenyl)-1,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-bis(phenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-methoxyphenyl)-6-ethyl mercaptan-1,3,5-triazine, and 2,2′-[6-(4-methoxyphenyl)-1,3,5-triazine-2,4-diyl]bis{5-[(2-ethylhexyl)oxy]phenol), or a combination thereof.

6 . A three-dimensional printing system, comprising:

a build material including from about 80 wt % to 100 wt % polymeric particles having a D50 particle size from about 10 μm to about 150 μm; and

a fusing agent including from about 0.5 wt % to about 20 wt % triazine radiation absorber solubilized in a liquid vehicle.

7 . The three-dimensional printing system of claim 6 , wherein the fusing agent exhibits an absorbance from about 0.3 to 2 at a wavelength from about 300 nm to about 500 nm.

8 . The tree-dimensional printing system of claim 6 , wherein the triazine radiation absorber is a triazine derivative compound selected from 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-isooctyloxyphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethyl phenyl)-6-(2-hydroxy-4-methoxy phenyl)1,3,5-triazine, 2-(2-hydroxy-4-hexyloxyphenyl)-4,6-bis(phenyl)-1,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-bis(phenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-methoxyphenyl)-6-ethyl mercaptan-1,3,5-triazine, and 2,2′-[6-(4-methoxyphenyl)-1,3,5-triazine-2,4-diyl]bis{5-[(2-ethylhexyl)oxy]phenol}, or a combination thereof.

9 . The three-dimensional printing system of claim 6 , wherein the polymeric particles are white, transparent, or translucent.

10 . The three-dimensional printing system of claim 6 , wherein the polymeric particles include polyacetal, polyacrylate, polyamide, polybutylene, polybutylene terephthalate, polycarbonate, polyester, polyether ketone, polyethylene terephthalate, polyethylene, polypropylene, polystyrene, polyurethane, thermoplastic polyamide, thermoplastic polyurethane, or a combination thereof.

11 . The three-dimensional printing system of claim 6 , further comprising a second fluid agent selected from a coloring agent that includes a liquid vehicle and a colorant or a detailing agent that includes a detailing compound that reduces a temperature of the build material onto which the detailing agent is applied.

12 . The three-dimensional printing system of claim 6 , further comprising:

a fluid ejector loaded or loadable with the fusing agent to eject the fusing agent onto a powder bed of the build material; and

a UV energy source that emits a peak wavelength from about from about 340 nm to about 415 nm at an energy level from about 2 W/cm 2 to about 50 W/cm 2 .

13 . A method for three-dimensional printing comprising:

iteratively applying individual build material layers of a polymer build material including from about 80 wt % to 100 wt % polymeric particles having a D50 particle size from about 10 μm to about 150 μm to a powder bed;

based on a three-dimensional object model, iteratively and selectively dispensing a fusing agent onto the individual build material layers, wherein the fusing agent includes from about 0.5 wt % to about 20 wt % triazine radiation absorber solubilized in a liquid vehicle; and

iteratively exposing the powder bed to light energy having a peak wavelength from about 340 nm to about 415 nm at an energy level from about 2 N/cm 2 to about 50 W/cm 2 for a time duration of about 0.05 second to about 10 seconds to selectively fuse the polymeric particles in contact with the triazine radiation absorber at the individual build material layers resulting in a fused three-dimensional object.

14 . The method of claim 13 , wherein the fused three-dimensional object is white, transparent, or translucent.

15 . The method of claim 13 , wherein based on the three-dimensional object model, the method further includes iteratively applying a second fluid agent to individual build material layers, wherein the second fluid agent is selected from a coloring agent that includes a liquid vehicle and a colorant, or a detailing agent that includes a detailing compound that reduces a temperature of the build material onto which the detailing agent is applied.

16 . A three-dimensionally printed object, comprising multiple fused composite layers including from about 80 wt % to 99.9 wt % polymer and from about 0.1 wt % to about 10 wt % triazine radiation absorber carried by the polymer.

17 . The three-dimensionally printed object of claim 16 , wherein polymer is white, transparent, or translucent.

18 . The three-dimensionally printed object of claim 16 , wherein the polymer is color-modified by a colorant so that the three-dimensionally printed object exhibits a color or tint.