Patent ID: 11920259
Assignee: ZHEJIANG ALMENG NEW MATERIAL TECHNOLOGY CO., LTD.
Field: Textile and paper machines (Mechanical engineering)
Classification: CPC D  Y | IPC D

Claim 0:
1. A method of preparing a washable flame retardant viscose fabric, wherein the viscose fabric comprises a flame retardant viscose fiber, and the method of comprises the following steps:
(1) impregnation: putting a cellulose pulp into an impregnation tank, wherein a temperature of an impregnation solution is 56-58° C., an impregnation time is 30-35 min, a concentration of the impregnation solution is 220-235 g/L, and V-388 used accounts for 0.08-0.10% of a content of methylcellulose;
(2) squeezing: squeezing and crushing a raw material with a squeezer, with a fixed weight-volume ratio of 130-140 g/L;
(3) ageing: subjecting a crushed raw material to an ageing at a temperature of 52-55° C., wherein an outlet copper viscosity is 50-52 nap;
(4) yellowing: adding carbon disulfide at an amount of 32-34% of the content of methylcellulose for yellowing for 25-35 min at a temperature of 25-30° C.;
(5) addition before spinning: before spinning, uniformly adding an aqueous dispersion of flame retardant, an aqueous dispersion of hyperbranched nanocellulose and a dispersant to a spinning glue using a pre-spinning injection system; wherein
the aqueous dispersion of flame retardant contains 180-200 g/L sodium metasilicate; the aqueous dispersion of hyperbranched nanocellulose contains 50-100 hyperbranched polyamide functionalized nanocellulose and ethylenediamine modified nanocellulose; and the sodium metasilicate accounts for 44-46% of the content of methylcellulose calculated based on silicon dioxide;
(6) spinning: a temperature of the coagulation bath is 45-55° C., a concentration of sulfuric acid is 110-135 g/L, a concentration of zinc sulfate is 25-35 g/L, a concentration of aluminum sulfate is 10-15 g/L, a concentration of sodium sulfate is 270-300 g/L, a concentration of orthosilicic acid is 10-15 WL, and an acid bath drop is 6-12 g/t;
(7) bundling: steam pressures before and after the bundling are 0.25 MPa and 0.15 MPa, respectively, a supplementary water temperature of a plasticizing tank is greater than or equal to 80° C., an acid content of the plasticizing tank is 20-35 g/L, a main condensation bridge temperature is less than or equal to 50° C., and a final condensation temperature is less than or equal to 25° C.;
(8) drafting: a drafting ratio from a spinneret to a godet is 30-60%, a drafting ratio from the godet to a first set is 20-40%, and a drafting ratio from the first set to a second set is 7-12%, and a total drafting ratio is 80-150%;
(9) cutting off;
(10) first washing: performing a washing at room temperature;
(11) desulfurization: conducting a desulfurization using a sodium sulfite solution, wherein a concentration of the sodium sulfite solution is 4-8 g/L, and a temperature of the sodium sulfite solution is 75-80° C.;
(12) second washing: performing a washing at room temperature;
(13) pickling: conducting a pickling using hydrochloric acid with a pH of 4-6 and room temperature;
(14) third washing: performing a washing at 45-55° C.;
(15) application of oil bath: an oil solution used has a concentration of 3-6 g/L, a temperature of 45-55° C., and a pH of 7-8.5;
(16) drying and packaging.