Three-dimensional printing with directionally-dependent reflective particles

A method of making a three-dimensional printed article, comprising:

• iteratively applying individual layers of a powder bed material to a powder bed, wherein the powder bed material comprises polymer-consisting particles mixed with directionally-dependent reflective particles, wherein the directionally-dependent reflective particles include polyethylene terephthalate (PET) particles having a reflective coating and having an X dimension length, a Y dimension width, and a Z dimension thickness that is no more than 10% of each of the X dimension length and the Y dimension width, and wherein the directionally-dependent reflective particles are chemically and thermally stable at a melting point temperature of the polymer-consisting particles;
• based on a three-dimensional object model, selectively applying a fusing agent onto the individual layers of powder bed material, wherein the fusing agent comprises water and a radiation absorber, wherein the radiation absorber absorbs radiation energy and converts the radiation energy to heat;
• and
• exposing the powder bed to radiation energy to selectively fuse the polymer-consisting particles in contact with the radiation absorber at individual layers and thereby form the three-dimensional printed article.