3d printer

A 3D printer having a binder jetting unit comprising:

• a powder supplying unit configured to accommodate a powder therein and supply the powder for forming a product;
• and
• a product forming unit located at one side of the powder supplying unit to irradiate a laser to the powder supplied from the powder supplying unit and sinter the powder so that a 3D product is formed,
• wherein the powder supplying unit for supplying the powder is disposed at an upper portion of one side of an output bed of the product forming unit, and a binder jetting unit is disposed at an upper portion of the other side of the output bed, which is opposite to the powder supplying unit, to discharge a binder only to a region to which laser is to be irradiated to melt the powder,
• wherein the powder supplying unit supplies the powder to the output bed while moving from one side to the other side of the output bed and then stops, the powder supplying unit and the binder jetting unit located at the other side of the output bed move together from the other side to one side of the output bed and stop after discharging the binder to a powder region in which the powder is to be melted in a state where the powder supplying unit stops the supply of powder, and a laser is irradiated to the powder region to which the binder is discharged so that the powder is melted and sintered, the above processes being repeated to output a final product.