Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a semi-crystalline thermoplastic polymer having a surface energy density greater than 41 mN/m. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline thermoplastic polymer in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a semi-crystalline or amorphous thermoplastic polymer having a predicted total dimension change during 3D printing ranging from about ?4% to about 9%. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline or amorphous thermoplastic polymer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber has absorption at wavelengths ranging from 800 nm to 4000 nm and has transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a thermoplastic elastomer having: an avalanche angle ranging from about 49 degrees to about 59 degrees; a break energy ranging from about 55 kJ/kg to about 78 kJ/kg; and an avalanche energy ranging from about 10 kJ/kg to about 27 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a polyamide having a melt enthalpy ranging from greater than 5 J/g to less than 150 J/g. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber is a plasmonic resonance absorber having absorption at wavelengths ranging from 800 nm to 4000 nm and having transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: An example of a three-dimensional (3D) printing composition includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes one of: (i) a thermoplastic elastomer having a flow parameter characterized by a consolidation resistance value ranging from about 8 to about 30, and a tap density characterized by an n1/2 value ranging from 5 taps to 30 taps; or (ii) a polyamide-like material having a flow parameter characterized by a consolidation resistance value ranging from about 75 to about 120, and a tap density characterized by an n1/2 value ranging from 5 taps to 30 taps. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer or the polyamide-like material in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a semi-crystalline or amorphous thermoplastic polymer having a predicted total dimension change during 3D printing ranging from about ?4% to about 9%. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline or amorphous thermoplastic polymer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber has absorption at wavelengths ranging from 800 nm to 4000 nm and has transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a semi-crystalline or amorphous thermoplastic polymer having a predicted total dimension change during 3D printing ranging from about ?4% to about 9%. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline or amorphous thermoplastic polymer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber has absorption at wavelengths ranging from 800 nm to 4000 nm and has transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a polyamide having: an avalanche angle ranging from about 35 degrees to about 55 degrees; a break energy ranging from about 25 kJ/kg to about 57 kJ/kg; and an avalanche energy ranging from about 7 kJ/kg to about 22 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a polyamide having a melt enthalpy ranging from greater than 5 J/g to less than 150 J/g. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber is a plasmonic resonance absorber having absorption at wavelengths ranging from 800 nm to 4000 nm and having transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a polyamide having: an avalanche angle ranging from about 35 degrees to about 55 degrees; a break energy ranging from about 25 kJ/kg to about 57 kJ/kg; and an avalanche energy ranging from about 7 kJ/kg to about 22 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a thermoplastic elastomer having: an avalanche angle ranging from about 49 degrees to about 59 degrees; a break energy ranging from about 55 kJ/kg to about 78 kJ/kg; and an avalanche energy ranging from about 10 kJ/kg to about 27 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes thermoplastic elastomer particles, wherein at least 70% of the thermoplastic elastomer particles, based on a number distribution, have an aspect ratio ranging from 0.75 to 1. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer particles in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing composition includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes one of: (i) a thermoplastic elastomer having a flow parameter characterized by a consolidation resistance value ranging from about 8 to about 30, and a tap density characterized by an n1/2 value ranging from 5 taps to 30 taps; or (ii) a polyamide-like material having a flow parameter characterized by a consolidation resistance value ranging from about 75 to about 120, and a tap density characterized by an n1/2 value ranging from 5 taps to 30 taps. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer or the polyamide-like material in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a thermoplastic elastomer having a melt enthalpy ranging from greater than 5 J/g to about 177 J/g. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber is a plasmonic resonance absorber having absorption at wavelengths ranging from 800 nm to 4000 nm and having transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a semi-crystalline or amorphous thermoplastic polymer having a predicted total dimension change during 3D printing ranging from about ?4% to about 9%. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline or amorphous thermoplastic polymer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber has absorption at wavelengths ranging from 800 nm to 4000 nm and has transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: Methods, arrays, and systems for electrochemical sensing are provided. An example of a method includes forming a number of first electrodes, forming a fluidic level having a number of walls that extend substantially vertically from each of the number of first electrodes, and forming a number of second electrodes in contact with the number of walls. In some examples, forming the fluidic level having the number of walls includes embossing an embossing resin.

Abstract: A fluid ejection device includes a thin film heater resistor portion having a heater resistor, and a two-layer structure disposed over the heater resistor. The two-layer structure includes a top layer and a bottom layer, with the top layer having a hardness that is at least 1.5 times greater than the hardness of the bottom layer.

Abstract: Methods, arrays, and systems for electrochemical sensing are provided. An example of a method includes forming a number of first electrodes, forming a fluidic level having a number of walls that extend substantially vertically from each of the number of first electrodes, and forming a number of second electrodes in contact with the number of walls. In some examples, forming the fluidic level having the number of walls includes embossing an embossing resin.

Abstract: A fluid ejection device includes a thin film heater resistor portion having a heater resistor, and a two-layer structure disposed over the heater resistor. The two-layer structure includes a top layer and a bottom layer, with the top layer having a hardness that is at least 1.5 times greater than the hardness of the bottom layer.