Three-dimensional printing and three-dimensional printers

An apparatus for printing at least one three-dimensional object, the apparatus comprising:

• a processing chamber configured to facilitate the printing of the at least one three-dimensional object, the processing chamber being configured to accommodate a first atmosphere;
• and
• a build module configured to accommodate the at least one three-dimensional object, the build module being configured to accommodate a second atmosphere,
• the processing chamber and the build module being configured to reversibly engage and disengage one another, the build module being configured to accommodate a positive pressure of the second atmosphere after the printing of the at least one three-dimensional object, the positive pressure being above ambient pressure external to the build module, and
• one or more of the following:
• (A) the apparatus further comprises an energy source configured to generate an energy beam that transforms a pre-transformed material into a transformed material as part of the printing of the at least one three-dimensional object;
• (B) the build module is configured to accommodate the positive pressure of the second atmosphere at a time including (i) after the printing of the at least one three-dimensional object, and (ii) after disengagement of the build module from the processing chamber;
• (C) the build module is configured to accommodate the at least one three-dimensional object during the printing;
• (D) the build module is configured to engage with a first shutter;
• (E) the processing chamber is configured to engage with a second shutter;
• (F) the build module comprises a reversibly closable shutter that is configured to maintain in the build module the second atmosphere excluding at least one component present in an ambient atmosphere, the at least one component present in the ambient atmosphere being a reactive agent, and the reversibly closable shutter being configured to facilitate excluding the reactive agent in the second atmosphere below a threshold value, the reactive agent being able to react with the pre-transformed material during the printing, the reversibly closable shutter being configured to exclude the reactive agent at least in part by keeping an amount of the reactive agent below the threshold value;
• or
• (G) any combination of (A), (B), (C), (D), (E), and (F).