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In thermodynamics, the enthalpy of sublimation, or heat of sublimation, is the heat required to sublimate (change from solid to gas) one mole of a substance at a given combination of temperature and pressure, usually standard temperature and pressure (STP). It is equal to the cohesive energy of the solid.
In order to transfer the image from the paper to the substrate, it requires a heat press process that is a combination of time, temperature and pressure. The heat press applies this special combination, which can change depending on the substrate, to “transfer” the sublimation dyes at the molecular level into the substrate.
As dye-sublimation page printers utilize heat to transfer the dye onto the print media, the printing speed is limited by the speed at which the elements on the thermal head can change temperature. Heating the elements is easy, as a strong electric current can raise the temperature of an element very quickly.
The form of the cooled surface often is a so-called cold finger which for very low-temperature sublimation may actually be cryogenically cooled. If the operation is a batch process , then the sublimed material can be collected from the cooled surface once heating ceases and the vacuum is released.
J.A. Dean (ed.), Lange's Handbook of Chemistry (15th Edition), McGraw-Hill, 1999; Section 6, Thermodynamic Properties; Table 6.4, Heats of Fusion, Vaporization, and Sublimation and Specific Heat at Various Temperatures of the Elements and Inorganic Compounds
The sublimation sandwich method (also called the sublimation sandwich process and the sublimation sandwich technique) is a kind of physical vapor deposition used for creating man-made crystals. Silicon carbide is the most common crystal grown this way, though other crystals may also be created with it (notably gallium nitride ).
The low temperature and direct sublimation to a gas makes dry ice an effective coolant, since it is colder than water ice and leaves no residue as it changes state. [4] Its enthalpy of sublimation is 571 kJ/kg (25.2 kJ/mol, 136.5 calorie/g). Dry ice is non-polar, with a dipole moment of zero, so attractive intermolecular van der Waals forces ...
Enthalpy change of sublimation at 273.15 K, Δ sub H: 51.1 kJ/mol Std entropy change of sublimation at 273.15 K, 1 bar, Δ sub S ~144 J/(mol·K) Molal freezing point constant: −1.858 °C kg/mol Molal boiling point constant: 0.512 °C kg/mol Solid properties Std enthalpy change of formation, Δ f H o solid: −291.83 kJ/mol Standard molar ...