Three dimensional printing material system and method

A compound used in three-dimensional printing, comprising:

• a dry particulate mixture of:
• a first dry particulate material comprising monocalcium phosphate, anhydrous;
• a second dry particulate material comprising magnesium oxide;
• and
• a third dry particulate material comprising polyvinyl alcohol, wherein the dry particulate mixture can be used in three-dimensional printing to form an article comprised of a plurality of layers, the first particulate material and the second particulate material can react to form a solid in a period of time, and the third particulate material can solidify in a longer period of time when the mixture is contacted by a fluid during three-dimensional printing.

A dry particulate mixture of solids used for three-dimensional printing that, when contacted by a fluid during three-dimensional printing to form an article comprised of a plurality of layers, undergoes a first solidification reaction beginning with the fluid contact and occurring at a first rate, and also undergoes a second solidification reaction beginning with the fluid contact and occurring at a second rate slower than the first rate, wherein the dry particulate mixture comprises:

• a first dry particulate material comprising monocalcium phosphate, anhydrous;
• a second dry particulate material comprising magnesium oxide;
• and
• a third dry particulate material comprising polyvinyl alcohol.