Abstract: A hardening agent for three-dimensional printing includes a boron-containing hardener and a jettable liquid vehicle, and is devoid of a pigment and a dye. The boron-containing hardener is selected from the group consisting of a water dispersible boron-containing hardener present in an amount ranging from about 6 wt % to about 15 wt %, and a water soluble boron-containing hardener present in an amount ranging from greater than 1 wt % to about 20 wt %.

Abstract: A three-dimensional printing kit includes a build material composition and a dielectric agent. The build material composition includes a fluorinated polymeric material having an effective relative permittivity (?r) value ranging from >3 to ?10,000. The dielectric agent includes a dielectric material having an effective relative permittivity (?r) value ranging from ?1.1 to about ?10,000.

Abstract: In an example three-dimensional printing method, individual layers of a metal-based build material are patterned, based on a 3D object model, with a binding agent to form an intermediate structure. A case-hardened portion of a 3D object is also patterned (based on the object model) by selectively depositing a hardening agent to deliver a predetermined concentration of a hardening element to at least one of the individual layers, wherein the individual layers are maintained below a vaporization temperature of the hardening agent during the selectively depositing. The intermediate structure is heated at a first rate to a temperature that aids in diffusion of the hardening element, and is held at the temperature for a predetermined time. The intermediate structure is cooled at a second rate. The intermediate structure, with the patterned case-hardened portion, is then sintered at a sintering temperature of the metal-based build material.

Abstract: A hardening agent for three-dimensional printing includes a boron-containing hardener and a jettable liquid vehicle, and is devoid of a pigment and a dye. The boron-containing hardener is selected from the group consisting of a water dispersible boron-containing hardener present in an amount ranging from about 6 wt % to about 15 wt %, and a water soluble boron-containing hardener present in an amount ranging from greater than 1 wt % to about 20 wt %.

Abstract: Charge generation layers comprise a charge generation compound and a binder which comprises polyvinylbutyral and phenolic resol. Dual layer photoconductors comprise the charge generation layer in combination with a substrate and a charge transport layer, in which the charge generation layer comprises a charge generation compound and a binder which comprises polyvinylbutyral and phenolic resol. Dual layer photoconductors comprise the charge generation layer in combination with a substrate and a charge transport layer, in which the charge generation layer comprises a charge generation compound and a binder which comprises polyvinylbutyral and a resin selected from the group consisting of phenol novolac and polyhydroxystyrene.

Abstract: A positive charging photoconductor of, preferably, 4 to 8 percent by weight metal-free phthalocyanine, 30-50 percent by weight tritolylamine and the remainder polyvinylbutyral.