Production of objects

{
  "publication_number": "US5120476A",
  "country": "US",
  "kind": "A",
  "title": "Production of objects",
  "abstract": "Three-dimensional objects are produced by the polymerization of a photopolymerizable liquid medium with the aid of high-energy radiation by continuously introducing the liquid medium in lamina form from a casting means onto the surface of a carrier liquid which has a higher specific gravity than the photopolymerizable medium and is not miscible therewith. This lamina is polymerized by irradiation to form a laminar, two-dimensional polymer layer, then the surface of the carrier liquid is raised and another lamina of the photopolymerizable medium is introduced onto the surface and polymerized to form a further polymer layer which combines with the preceding one. These steps are repeated until the three-dimensional object is formed. The steps of forming the polymer lamina and raising the surface of the carrier liquid may be computer controlled.",
  "claims": [
    "1. A process for producing a three-dimensional object by polymerizing a photopolymerizable liquid medium with high-energy radiation by a) producing a laminar, two-dimensional polymer layer on a surface of a carrier liquid, b) raising the surface of the carrier liquid by an amount which corresponds to a thickness of the laminar polymer layer and then again producing a two-dimensional polymer layer which connects to the preceding one, and c) repeating steps a) and b) until a three-dimensional object is formed, which comprises continuously introducing onto the surface of the carrier liquid, from a casting means, a lamina of a photopolymerizable liquid medium, which has a lower specific gravity than the carrier liquid and is not miscible therewith, and then polymerizing the photopolymerizable liquid medium by irradiation of the entire photopolymerizable liquid surface uninterruptedly.",
    "2. A process for producing an object as claimed in claim 1, wherein the photopolymerizable liquid medium comprises an ethylenically unsaturated acrylic or vinyl compound and a photoinitiator.",
    "3. A process for producing an object as claimed in claim 1, wherein the photopolymerizable liquid medium is thixotropic.",
    "4. A process for producing an object as claimed in claim 1, wherein the carrier liquid onto whose surface the photopolymerizable liquid medium is introduced is an aqueous salt solution.",
    "5. A process for producing an object as claimed in claim 1, wherein the introduction of the lamina from the casting means onto the surface of the carrier liquid is computer controlled."
  ],
  "cpc": [
    "B29C 64/135",
    "B29K 2995/0073",
    "B33Y 10/00",
    "B33Y 70/00"
  ],
  "assignees": [
    "BASF AG"
  ],
  "filing_date": "1990-12-14",
  "publication_date": "1992-06-09",
  "grant_date": "1992-06-09",
  "priority_date": "1989-12-23",
  "application_number": "US-62735490-A",
  "family_id": "6396371",
  "citations": [
    "US4575330A",
    "US4575330B1",
    "US4749347A",
    "US4961154A"
  ]
}