A functional layer forming ink used in forming a functional layer of the self-luminous element by a printing method, the ink including functional material dissolved or dispersed in a mixed solvent including solvents having different boiling points. When one or more solvents are selected from the solvents of the mixed solvent in descending order of boiling point until a mass ratio of the selection to the mixed solvent is a defined ratio or more, the one or more solvents in the selection are included in a solvent group of solvents that have a contact angle of 5° or less with respect to a defined resin material.

Embodiments of the present disclosure may include a method including assembling at least two building elements together. Embodiments may also include applying a stimulus to at least one of the at least two building elements, the stimulus being capable of changing a color of at least a portion of the one of the at least two building elements. In some embodiments, the at least two building elements may be assembled together prior to applying the stimulus.

Embodiments of the present disclosure may include a method including assembling at least two building elements together. Embodiments may also include applying a stimulus to at least one of the at least two building elements, the stimulus being capable of changing a color of at least a portion of the one of the at least two building elements. In some embodiments, the at least two building elements may be assembled together prior to applying the stimulus.

A method of manufacturing of an ink (100) composition comprises a biphasic ligand exchange process. A first phase liquid (10) comprising a nonpolar solvent (11) with a colloidal suspension of nanoparticles (1) that are capped with a shell of non polar ligands (2) is contacted with a second phase liquid (20) comprising a polar solvent (21) with second ligand (3). The second ligand comprises at least one surface binding head group that has an affinity for binding to the nanoparticle; and an ionically charged tail group. The second ligands displace the first ligands to form a dispersion of the nanoparticles that are capped with a shell of the second ligands in the second phase liquid. The nanoparticles can be separated from the second phase liquid. The separated nanoparticles can be (re)dispersed in a printable liquid medium, e.g. used for printing a photoactive layer.

A method of manufacturing of an ink (100) composition comprises a biphasic ligand exchange process. A first phase liquid (10) comprising a nonpolar solvent (11) with a colloidal suspension of nanoparticles (1) that are capped with a shell of non polar ligands (2) is contacted with a second phase liquid (20) comprising a polar solvent (21) with second ligand (3). The second ligand comprises at least one surface binding head group that has an affinity for binding to the nanoparticle; and an ionically charged tail group. The second ligands displace the first ligands to form a dispersion of the nanoparticles that are capped with a shell of the second ligands in the second phase liquid. The nanoparticles can be separated from the second phase liquid. The separated nanoparticles can be (re)dispersed in a printable liquid medium, e.g. used for printing a photoactive layer.

An aqueous peelable ink composition with color-changing comprises: at least one film-forming elastomeric polymer, at least one polyoxyethylene sorbitan ester, at least one dye, at least one pigment, and water, wherein the film-forming elastomeric polymer (a) is acrylonitrile butadiene rubber (NBR) and/or hydrogenated acrylonitrile butadiene rubber (HNBR).

An aqueous peelable ink composition with color-changing comprises: at least one film-forming elastomeric polymer, at least one polyoxyethylene sorbitan ester, at least one dye, at least one pigment, and water, wherein the film-forming elastomeric polymer (a) is acrylonitrile butadiene rubber (NBR) and/or hydrogenated acrylonitrile butadiene rubber (HNBR).

A smart ink, comprising microparticles, with each microparticle comprising: a) an exterior shell; b) a liquid encapsulated within the shell; and c) a Janus microparticle suspended in the liquid, wherein the Janus microparticle either comprises: i) two or more distinct assemblies of particles; or ii) a core loaded with particles, the core having a first surface portion and a second surface portion that is functionally distinct from the first surface portion. An apparatus and method for production of the microparticles are also provided.

An aspect of the present disclosure is a nanocrystal that includes a nanocrystal core and a ligand coordinated to a surface of the nanocrystal core, where the ligand includes a functionalized aromatic molecule. In some embodiments of the present disclosure, the functionalized aromatic molecule may include at least one of cinnamic acid (CAH) and/or a functionalized CAH molecule.

An aspect of the present disclosure is a nanocrystal that includes a nanocrystal core and a ligand coordinated to a surface of the nanocrystal core, where the ligand includes a functionalized aromatic molecule. In some embodiments of the present disclosure, the functionalized aromatic molecule may include at least one of cinnamic acid (CAH) and/or a functionalized CAH molecule.