Patents Represented by Attorney, Agent or Law Firm Pillsbury, Madison & Sutro, LLP Intellectual Property Grp
  • Patent number: 6200354
    Abstract: A method of dyeing cellulosic fibers or fabrics using pre-metallized acid dye by pretreating the fabric with a cationic agent having a plurality of cationic centers and optionally after treating the dyed material with a cationic polymer is disclosed. The cationic polymer is desirably a polyquaternary amine material especially a poly(DADMAC) or polyvinylpyridine. Material dyed by the method has a “washed out” appearance similar to fabrics dyed using the “Jarofast” process, but the availability of a wide range of pre-metallized dyes gives a wider color range, and the method enables a wider range of substrates to be dyed successfully, including lyocell fiber materials e.g. those sold under Courtauld's trademark “Tencel” and blend/union materials with polyamides, easier processing and superior wash and light fastness.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: March 13, 2001
    Assignee: Imperial Chemical Industries PLC
    Inventors: Geoffrey William Collins, Stephen Martin Burkinshaw, Roy Gordon