Patent ID: 8840758

Claim:
A process for producing a microfiber product stream, said process comprising: (A) contacting short cut multicomponent fibers having a length of less than 25 millimeters with a heated aqueous stream in a mix zone to produce a short cut multicomponent fiber slurry; wherein said short cut multicomponent fibers comprise at least one water dispersible sulfopolyester and at least one water non-dispersible polymer immiscible with said water dispersible sulfopolyester; and wherein said heated aqueous stream is at a temperature of 40° C. or greater; (B) mixing said short cut multicomponent fiber slurry and optionally, a heated aqueous stream, in a fiber opening zone for a sufficient time to remove a portion of said water dispersible sulfopolyester to produce an opened microfiber slurry at a temperature in the range of about 55° C. to about 100° C.; wherein said opened microfiber slurry comprises water non-dispersible polymer microfiber, water dispersible sulfopolyester, and water; wherein the weight % of solids in said opened microfiber slurry ranges from 0.1 weight % to about 20 weight %; wherein said water non-dispersible polymer microfiber has a minimum transverse dimension of less than 10 microns; and wherein at least about 50 weight % of said water non-dispersible polymer microfiber is suspended in said opened microfiber slurry; (C) routing said opened microfiber slurry to a primary solid liquid separation zone to produce said microfiber product stream and a first mother liquor stream; wherein said first mother liquor stream comprises water and said water dispersible sulfopolyester; and D) routing at least a portion of said first mother liquor stream to a second solid liquid separation zone to produce a secondary wet cake stream and a second mother liquor stream; wherein said second mother liquor stream comprises water and water dispersible sulfopolyester; and wherein said secondary wet cake stream comprises microfiber.