Silicone foam and method for making it

• US 4,859,712 A
• Filed: 10/12/1988
• Issued: 08/22/1989
• Est. Priority Date: 10/12/1988
• Status: Expired due to Term

• Current Assignee: Allergan Incorporated (Abbvie Incorporated)
• Original Assignee: Cox-Uphoff International
• Inventors: Cox, James E.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US07/256,648
• Time in Patent Office: 314 Days
• Field of Search: 521/61, 521/154
• US Class Current: 521/62
• CPC Class Codes: A61L 27/34 Macromolecular materials
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: C08J 2201/0446 Elimination of NaCl only
• CPC Class Codes: C08J 2383/04 Polysiloxanes
• CPC Class Codes: C08J 9/26 by elimination of a solid phase from a macromolecular composition or article, e.g. leaching out
• CPC Class Codes: C08L 83/04 Polysiloxanes

Abstract

A method to make a silicone foam. A layer of crystalline material is embedded in a layer of uncured silicone. The crystalline material is closely packed in crystal-to-crystal contact, the crystals being provided in a plurality of sizes or ranges of size to increase the packing ratio of the crystals as a group. The silicone is cured and then the crystals are dissolved out with a solvent that dissolves them but does not dissolve the silicone.

Claims

1. The method of preparing a silicone foam comprising embedding in a layer of uncured silicone a layer of crystalline material, the crystalline material being closely packed and generally in crystal-to-crystal contact, and embraced by the liquid silicone, curing the silicone, and with a solvent which dissolves the crystals but does not dissolve the cured silicone dissolving out the crystals, the crystals being provided in a plurality of sizes or ranges of sizes to increase the packing ratio of the crystals as a group whereby to produce a structure of said cured silicone having a great number of tendrils and intercommunicating cavities.

2. The method of claim 1 in which the crystals are sodium chloride, and the solvent is water.