▁have ▁been ▁pat ent ▁law su its ▁concerning ▁ 3 - D ▁printing ▁for ▁manufact uring . ▁ ▁Rap id ▁pro tot yp ing ▁▁ ▁Indust rial ▁ 3 D ▁printer s ▁have ▁existed ▁since ▁the ▁early ▁ 1 9 8 0 s ▁and ▁have ▁been ▁used ▁extens ively ▁for ▁rapid ▁pro tot yp ing ▁and ▁research ▁purposes . ▁These ▁are ▁generally ▁larger ▁machines ▁that ▁use ▁propriet ary ▁pow der ed ▁met als , ▁casting ▁media ▁( e . g . ▁sand ), ▁pl ast ics , ▁paper ▁or ▁cart rid ges , ▁and ▁are ▁used ▁for ▁rapid ▁pro tot yp ing ▁by ▁univers ities ▁and ▁commercial ▁companies . ▁ ▁Research ▁▁ 3 D ▁printing ▁can ▁be ▁particularly ▁useful ▁in ▁research ▁l abs ▁due ▁to ▁its ▁ability ▁to ▁make ▁special ized , ▁bes po ke ▁geomet ries . ▁In ▁ 2 0 1 2 ▁a ▁proof ▁of ▁principle ▁project ▁at ▁the ▁University ▁of ▁Glasgow , ▁UK , ▁showed ▁that ▁it ▁is ▁possible ▁to ▁use ▁ 3 D ▁printing ▁techniques ▁to ▁assist ▁in ▁the ▁production ▁of ▁chemical ▁comp ounds . ▁They ▁first ▁printed ▁chemical ▁reaction ▁vessels , ▁then ▁used ▁the ▁printer ▁to ▁depos it ▁react ants ▁into ▁them . ▁They ▁have ▁produced ▁new ▁comp ounds ▁to ▁verify ▁the ▁valid ity ▁of ▁the ▁process , ▁but ▁have ▁not ▁purs ued ▁anything ▁with ▁a ▁particular ▁application . ▁ ▁Usually , ▁the ▁F DM ▁process ▁is ▁used ▁to ▁print ▁h ollow ▁reaction ▁vessels ▁or ▁mic r ore act ors . ▁If ▁the ▁ 3 D ▁print ▁is