Patent ID: 6855790

Claim:
A nonwoven fabric, comprising: fibrous material, and a binder material comprising a binder composition comprising an ion-sensitive polymer comprising a first repeat unit derived from a monomer selected from styrenesulfonic acid (SS), a sodium salt of styrenesulfonic acid (NaSS), 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), a sodium salt of 2-acrylamido-2-methyl-1-propanesulfonic acid (NaAMPS), vinylsulfonic acid, a sodium salt of vinylsulfonic acid, and combinations thereof; a second repeat unit derived from a monomer selected from acrylic acid, a sodium salt of acrylic acid, methacrylic acid, a sodium salt of methacrylic acid, and combinations thereof; and a third repeat unit derived from a monomer selected from at least one alkyl acrylate, at least one alkyl methacrylate, and combination thereof; wherein the fabric is not substantially water-dispersible in a neutral salt solution containing at least about 0.3 weight percent salt, said salt comprising one or more monovalent or multivalent ions; and the fabric is substantially water-dispersible in tap water containing one or more multivalent ions.