US Patent 11400650 Methods and systems for stereolithography three-dimensional printing

The present disclosure provides method and systems for printing a three-dimensional (3D) object. A method for 3D printing may comprise providing a mixture comprising (i) a polymeric precursor, (ii) a photoinitiator configured to initiate formation of a polymeric material from the polymeric precursor, and (iii) a photoinhibitor configured to inhibit the formation of the polymeric precursor. The method may comprise exposing the mixture to (i) a first light to cause the photoinitiator to initiate formation of the polymeric material, thereby to print the 3D object, and (ii) a second light to cause the photoinhibitor to inhibit the formation of the polymeric material. During printing of the 3D object, a ratio of (i) an energy of the second light sufficient to initiate formation of the polymeric material relative to (ii) an energy of the first light sufficient to initiate formation of the polymeric material may be greater than 1.