Compositions and methods for use in three dimensional model printing

Abstract

Embodiments of the invention are directed to a method of producing three-dimensional prototype molds for use in investment casting. The method includes dispensing modeling material and support material in a predetermined arrangement, in layers, to produce a three-dimensional mold having an outer shell. Generally, the out shell includes modeling material and the interior of the mold includes support material. Then the mold is cured.

1 . A method of producing three-dimensional prototype molds for use in investment casting, the method comprising: 
 dispensing modeling material and support material in a predetermined arrangement, in layers, to produce a three-dimensional mold having an outer shell such that the outer shell comprises modeling material and the interior of the mold comprises support material; and    curing the mold.    
   
   
       2 . The method of  claim 1 , wherein dispensing comprises dispensing such that the outer shell comprises predominantly modeling material.  
   
   
       3 . The method of  claim 1 , wherein dispensing comprises dispensing such that the interior comprises predominantly support material.  
   
   
       4 . The method of  claim 1 , wherein dispensing comprises dispensing such that the outer shell comprises only modeling material.  
   
   
       5 . The method of  claim 1 , wherein dispensing comprises constructing a grid of modeling material within the support material.  
   
   
       6 . The method of  claim 1 , wherein dispensing comprises dispensing such that the wall thickness of the outer shell is between 0.5 mm to 0.9 mm.  
   
   
       7 . The method of  claim 1  wherein curing the mold comprises curing the outer shell to form a solid shell of modeling material around a semi-solid filling of support material.  
   
   
       8 . The method of  claim 1 , wherein the interior of the mold remains semi-solid after curing.  
   
   
       9 . The method of  claim 1 , wherein the three-dimensional mold is produced by a three-dimensional printer.  
   
   
       10 . The method of  claim 1 , further comprising a process of preparing a cast from said mold, said process comprising casting the cured mold in a heat resistant substance to form a cast.  
   
   
       11 . The method of  claim 10  further comprising heating the cast using a heat source to burn away or dissipate the mold.  
   
   
       12 . The method of  claim 11 , wherein after heating the cast, the mold burns away without swelling.  
   
   
       13 . The method of  claim 11 , wherein after heating the cast, the mold dissipates or burns away without leaving traces of the modeling and support materials inside the cast.  
   
   
       14 . The method of  claim 10 , wherein the heat-resistant substance is ceramic material.  
   
   
       15 . A prototype mold for use in investment casting having an outer shell comprising modeling material and an interior comprising support material, said prototype mold being produced by three dimensional printing.  
   
   
       16 . The prototype mold of  claim 15  wherein said outer shell comprises predominantly modeling material  
   
   
       17 . The prototype mold of  claim 15  wherein the outer shell is a solid shell of modeling material.  
   
   
       18 . The prototype mold of  claim 15  wherein the interior comprises a grid of modeling material within the support material.  
   
   
       19 . The prototype mold of  claim 15  wherein the interior remains semi-solid when cured.  
   
   
       20 . The prototype mold of  claim 15 , wherein the wall thickness of the outer shell is between 0.5 mm to 0.9 mm.  
   
   
       21 . The prototype mold of  claim 15  wherein said mold is cast in a heat resistant substance.  
   
   
       22 . The prototype mold of  claim 21 , wherein said heat resistant substance is a ceramic material.