×

Method of making compressed sponges

  • US 2,659,935 A
  • Filed: 03/18/1950
  • Issued: 11/24/1953
  • Est. Priority Date: 03/18/1950
  • Status: Expired due to Term
First Claim
Patent Images

1. THE METHOD OF MAKING A COMPRESSED SPONGE WHICH COMPRISES PROVIDING A POLYVINYL FORMAL SPONGE HAVING INTERCONNECTED PORES THROUGHOUT, PREPARED FROM POLYVINYL ALCOHOL AND HAVING FROM 35 TO 80% OF THE HYDROXYL GROUPS OF THE ALCOHOL REACTED, SAID SPONGE CONTAINING NOT MORE THAN ABOUT 3% WATER, AND COMPRESSING SAID SPONGE UNDER A PRESSURE SUFFICIENT TO REDUCE MATERIALLY THE BULK OF SAID SPONGE, SAID SPONGE BEING MAINTAINED DURING THE COMPRESSING STEP AT A TEMPERATURE LESS THAN THAT AT WHICH THE SPONGE ASSUMES A PERMANENT SET.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×