Method and system for fabricating object featuring properties of a blood vessel

Abstract

A tubular structure fabricated by additive manufacturing from non-biological building material formulations, and featuring an elongated core, a shell encapsulating the core and an intermediate shell between the core and the shell. Each of the core, the shell and the intermediate shell is made of a different material or a different combination of materials. Both the core and the intermediate shell are sacrificial. Additive manufacturing of the tubular structure is usable for fabricating an object featuring properties of a blood vessel.

What is claimed is: 
     
         1 . A tubular structure fabricated by additive manufacturing from non-biological building material formulations, and comprising:
 an elongated core, a shell encapsulating said core and an intermediate shell between said core and said shell, each of said core, said shell and said intermediate shell being made of a different material or a different combination of materials, wherein both said core and said intermediate shell are sacrificial, and wherein one of said intermediate shell and said core is made of a hardened support material, and another one of said intermediate shell and said core is made of a liquid or liquid-like material.   
     
     
         2 . The tubular structure of  claim 1 , wherein said intermediate shell is made of said hardened support material, and said core is made of said liquid or liquid-like material. 
     
     
         3 . The tubular structure of  claim 1 , wherein said core is made of said hardened support material, and said intermediate shell is made of said liquid or liquid-like material. 
     
     
         4 . The tubular structure according to  claim 2 , wherein said liquid or liquid-like material is characterized by at least one of:
 a viscosity of no more than 10000 centipoises;   Shear loss modulus to Shear storage modulus ratio greater than 1;   a Shear modulus lower than 20 kPa;   flowability when subjected to a positive pressure of no more than 1 bar;   a shear-thinning and/or thixotropic behavior; and   a thermal-thinning behavior.   
     
     
         5 . The tubular structure according to  claim 1 , having a shape of a blood vessel. 
     
     
         6 . The tubular structure according to  claim 1 , wherein said shell is embedded in a supporting structure. 
     
     
         7 . The tubular structure according to  claim 6 , wherein said supporting structure is sacrificial. 
     
     
         8 . An object fabricated by additive manufacturing from non-biological building material formulations, the object has a shape of an organ and comprising: at least one structure having a shape of a blood vessel and at least one structure having a shape of a bodily structure other than a blood vessel, wherein said structure having said shape of said blood vessel is the tubular structure according to  claim 1 . 
     
     
         9 . An object fabricated by additive manufacturing from non-biological building material formulations, the object comprises an interconnected network of elongated structures, each having a shape of a blood vessel and being according to  claim 1 . 
     
     
         10 . The tubular structure according to  claim 1 , further comprising reinforcing elements embedded in said shell. 
     
     
         11 . The tubular structure according to  claim 10 , wherein said reinforcing elements are oriented to effect anisotropic mechanical properties of said shell. 
     
     
         12 . The tubular structure according to  claim 10 , wherein said reinforcing elements comprise at least one elongated reinforcing element embedded in said shell parallel to a longitudinal axis of said shell. 
     
     
         13 . The tubular structure according to  claim 10 , wherein said reinforcing elements comprise at least one annular reinforcing element embedded in said shell along an azimuthal direction defining said shell. 
     
     
         14 . The tubular structure according to  claim 13 , wherein said reinforcing elements comprise at least one elongated reinforcing element embedded in said shell parallel to a longitudinal axis of said shell. 
     
     
         15 . The tubular structure according to  claim 10 , wherein said reinforcing elements are made of a material having a tensile strength of from about 2 to about 4 MPa according to ASTM D-412. 
     
     
         16 . The tubular structure according to  claim 10 , wherein said reinforcing elements are made of a material having a Shore A hardness from about 25 MPa to about 35 MPa according to ASTM D-224D. 
     
     
         17 . The tubular structure according to  claim 10 , wherein said reinforcing elements are made of a material which comprises an elastomeric curable material and silica particles. 
     
     
         18 . The tubular structure according to  claim 1 , further comprising a liner layer at least partially coating an inner surface of said shell, between said intermediate shell and said inner surface, wherein an attachment between said liner layer and said shell is stronger than an attachment between said intermediate shell and said liner layer. 
     
     
         19 . The tubular structure or object according to  claim 15 , wherein said liner layer is harder than said shell. 
     
     
         20 . The tubular structure or object according to  claim 15 , wherein said liner layer has mechanical properties of plaque tissue.