Water soluble rapid prototyping support and mold material

• US 6,070,107 A
• Filed: 05/20/1998
• Issued: 05/30/2000
• Est. Priority Date: 04/02/1997
• Status: Expired due to Term

• Current Assignee: Advanced Ceramics Research LLC
• Original Assignee: Stratasys Incorporated
• Inventors: Popovich, Dragan, Lombardi, John Lang, Artz, Gregory John
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): Garland, Steven R.
• Application Number:
  US09/082,064
• Time in Patent Office: 741 Days
• Field of Search: 264/40.7, 264/308, 427/389.7, 700/119, 700/182
• US Class Current: 700/119
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 70/10 Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials

Abstract

A water-soluble thermoplastic composition for three-dimensional modeling comprising poly(2-ethyl-2-oxazoline) is disclosed. The composition in the form of an extrudable object may be extruded by an extrusion apparatus in a programmed pattern onto a base as a ribbon of liquified polymer to create a support structure for a prototype object or to create a water-soluble polymeric element.

Claims

1. A method for forming prototype mechanical elements from at least one polymer material on a platform comprising the steps of:

a) positioning a cylindrical rod of said polymer material comprising poly(2-ethyl-2-oxazoline) blended with at least one inert filler in a cylindrical housing having a throughbore with a diameter substantially equal to the diameter of the cylindrical rod, said housing being connected with and attached to a discharge head member having a uniform diameter bore connecting with the throughbore, a discharge tip, a reduced diameter discharge opening in the tip, and a circumferential heater to liquify the material in the bore;

b) compressing the material in the housing with a piston while simultaneously liquefying the material in the head member to thereby discharge a ribbon of material from the tip;

c) transporting the platform in the x and y directions while discharging material thereon to form the cross sectional shape of the element; and

d) transporting the housing and head member in the z direction simultaneously to form the element in elevation.

2. The method of claim 1 wherein the inert filler is selected from the polymer filler group consisting of calcium carbonate, glass spheres, graphite, carbon black, carbon fiber, glass fiber, talc, wollastonite, mica, alumina, silica, and silicon carbide.

3. A method for forming prototype mechanical elements from at least one polymer material on a platform comprising the steps of:

a) placing filament containing said polymer material comprising poly(2-ethyl-2-oxazoline) blended with at least one inert filler in a cylindrical housing having a throughbore with a diameter substantially equal to the diameter of the filament, said housing being connected with and attached to a discharge head member having a uniform diameter bore connecting with the throughbore, a discharge tip, a reduced diameter discharge opening in the tip, and a circumferential heater to liquefy the material in the bore;

b) liquefying the material in the head member to thereby discharge a ribbon of material from the tip;

c) transporting the platform in the x and y directions while discharging material thereon to form the cross sectional shape of the element; and

d) transporting the housing and head member in the z direction simultaneously to form the element in elevation.

4. The method of claim 3 wherein the inert filler is selected from the polymer filler group consisting of calcium carbonate, glass spheres, graphite, carbon black, carbon fiber, glass fiber, talc, wollastonite, mica, alumina, silica, and silicon carbide.

5. A method for forming prototype mechanical elements from at least one polymer material on a platform comprising the steps of:

a) placing filament containing said polymer material comprising poly(2-ethyl-2-oxazoline) and an alcohol plasticizer, wherein the modulus of poly(2-ethyl-2-oxazonline) is decreased by the addition of the alcohol plasticizer, in a cylindrical housing having a throughbore with a diameter substantially equal to the diameter of the filament, said housing being connected with and attached to a discharge head member having a uniform diameter bore connecting with the throughbore, a discharge tip, a reduced diameter discharge opening in the tip, and a circumferential heater to liquefy the material in the bore;

b) liquefying the material in the head member to thereby discharge a ribbon of material from the tip;

c) transporting the platform in the x and y directions while discharging material thereon to form the cross sectional shape of the element; and

d) transporting the housing and head member in the z direction simultaneously to form the element in elevation.

6. The method of claim 5 wherein the alcohol plasticizer is water soluble and comprises multiple hydroxyl groups.

7. The method of claim 5 wherein polar wax is added to the poly(2-ethyl-2-oxazoline) and alcohol plasticizer.

8. The method of claim 7 wherein the polar wax is selected from the group consisting of compounds having alcohol, acid, ester or amide functional groups.

9. The method of claim 5 wherein polar homopolymers and copolymers are added to the PEG plasticized poly(2-ethyl-2-oxazoline).

10. The method of claim 9 wherein the polar homopolymers and copolymers that are added to the PEG plasticized poly(2-ethyl-2-oxazoline) are from the group consisting of Nylon 12, amorphous nylon copolymer of terephthalamide/isophthalamide/hexamethylenediamide, Nylon 6/Nylon 12 copolymer, polyvinylformal, polyvinylbutyral, and polyesters.

11. Depositing a water-soluble thermoplastic composition as a ribbon of material to form a three-dimensional solid object, the composition forming the ribbon comprising poly(2-ethyl-2-oxazoline) and an inert filler.