Process for producing direct tooling mold and method for using the same

• US 6,355,196 B1
• Filed: 03/16/1998
• Issued: 03/12/2002
• Est. Priority Date: 03/16/1998
• Status: Expired due to Fees

• Current Assignee: Huntsman Advanced Materials Americas, Inc.
• Original Assignee: Vantico Inc. (Huntsman Corporation)
• Inventors: Filipiak, Kenneth R., Schwarting, David D., Kukulies, Brian H., Kotnis, Mahesh Arvind
• Primary Examiner(s): McDowell, Suzanne E.
• Application Number:
  US09/039,765
• Time in Patent Office: 1,457 Days
• Field of Search: 264/219, 264/328.1, 264/337, 264/331.13, 249/134, 249/331.19
• US Class Current: 264/219
• CPC Class Codes: B29C 33/3842 Manufacturing moulds, e.g. shaping the mould surface by machining
• CPC Class Codes: B29C 33/40 Plastics, e.g. foam or rubber
• CPC Class Codes: B29K 2863/00 Use of EP, i.e. epoxy resins or derivatives thereof as mould material
• CPC Class Codes: B29K 2875/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as mould material

Abstract

The present invention relates to a method for making a prototype by providing at least one polymeric board material having a glass transition temperature less than the molten temperature of a thermoplastic molding material and removing at least a portion of the polymeric board material to form, according to a computer-aided design, a reverse image of a desired article to be molded. Selected molten polymeric molding material is injected into the resulting mold to produce the desired prototype.

Claims

1. A method for manufacturing a prototype, comprising the steps of:

(a) providing a cured polymeric material;

(b) forming a mold having a cavity from the cured polymeric material by computer-aided design; and

(c) injecting a molten polymeric molding material into the cavity to produce the prototype.

2. A method according to claim 1, wherein the forming step is carried out by CNC machining.

3. A method according to claim 2, wherein the cured polymeric material is based on (i) a polyurethane-forming composition or (ii) a composition comprising an epoxy resin having, on average, more than one glycidyl group per molecule and a curing agent for the epoxy resin.

4. A method according to claim 3, wherein the cured polymeric material is based on a polyurethane-forming composition comprising:

a polyisocyanate component comprising monomeric diisocyanatodiphenylmethane isomers, polymethylene polyphenyl isocyanate, 4,4′

-isophenylmethane diisocyanate, toluene diisocyanate, phenylindane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, or 2,2,4-trimethylenehexamethylene diisocyanate; and

a polyol component comprising a) a polyol having a hydroxyl equivalent weight of up to about 150 and a functionality of 4 to 8, b) a polyether-polyol having a hydroxyl equivalent weight of more than 1900 and a functionality of 2 to 4, or c) a propylene glycol having a functionality of 2 to 4 or a polytetrahydrofuran, each having a hydroxyl equivalent weight of 150 to 500.

5. A method according to claim 3, wherein the cured polymeric material comprises:

cured mixtures of low viscosity bisphenol-A resins;

non-advanced polyglycidyl ethers of 2,2-bis(4′

-hydroxyphenyl) propane (bisphenol A);

2,2′

-bis(3′

-5′

-dibromo-4′

-hydroxyphenyl)methane (tetrabromobisphenol A);

bis(4-hydroxyphenyl)methane (bisphenol F);

or

advanced novolaks thereof.

6. A method according to claim 3, wherein the cured polymeric material is an epoxy-isocyanate resin.

7. A method according to claim 2, wherein the polymeric molding material is a thermoplastic.

8. A method according to claim 7, wherein the thermoplastic is polypropylene, acrylonitrile-butadiene-styrene copolymer, or polycarbonate.

9. A method according to claim 2, wherein the cured polymeric material is in the form of a block.

10. A method according to claim 2, wherein during the injecting step the polymeric molding material is subjected to a pressure of at least about 1200 psi plastic pressure.

11. A method according to claim 2, wherein during the injecting step the polymeric molding material is heated to a temperature between about 350°

F. to about 600°

F.

12. A method according to claim 2, wherein the polymeric molding material is substantially identical to a selected polymeric material of which a final article is made.

13. A method for manufacturing a mold, comprising the steps of:

(a) providing a cured polymeric material; and

(b) forming a mold having a cavity from the cured polymeric material by computer-aided design.

14. A method according to claim 13, wherein the forming step is carried out by CNC machining.