Method for producing regenerated cellulose-based threads and felted cloths
AssigneeRefiberd, Inc.
InventorsSarika Bajaj, Tushita Gupta, Mingyue Wang
Life of this patent
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Abstract
The present invention is directed to efficient methods for producing contiguous threads or felted cloths from recycled cellulose-based waste. The contiguous thread produced is suitable to be sowed on a cloth; it is small enough to go through the pore of a needle, it is strong enough to hold together, and it is bendable and not disintegrated into fragments. The contiguous thread and felted cloth made by the present invention maintain their original dye color of the recycled cellulose waste, and they do not need to be re-dyed.
Claims8
A method for producing a contiguous thread from regenerated cellulose-based textiles, comprising the steps of:
- (a) grinding cellulose-based textile materials into first fibers having length less than 1 cm,
- (b) depolymerizing the first fibers in an acidic solution of pH 1-4 in a pressurized and
- heated chamber at 50-150° C. and 10-15 psi of chamber pressurization,
- (c) removing the acidic solution from the depolymerized fibers and drying the depolymerized fibers,
- (d) dissolving the dried fibers of (c) into an aqueous alkali solution containing 6-20% by weight of an alkali through mechanical agitation, at temperature between −8° C. to −30° C., to make a gelled cellulose solution,
- (e) degassing the gelled cellulose solution under vacuum to produce a gelled and degassed solution, and
- (f) extruding the gelled and degassed solution through a membrane having 0.25-1 mm pore size into a second acidic solution of pH 1-4 to polymerize the cellulose into fibers and connecting the fibers into the contiguous thread.
Dependencies are inferred from the claim text.