Cotton fiber pretreatment process with stepped temperature rise

The invention discloses a step-heating cotton fiber pretreatment process which comprises the following steps: step 1) adding materials at normal temperature: putting cotton fibers into a scouring and bleaching solution, and adding a KA pretreatment agent into the scouring and bleaching solution; (2) primary heating and heat preservation: after the primary heating temperature reaches 45-55 DEG C, heat preservation is conducted for 20 min; 3) secondary charging: adding caustic soda and hydrogen peroxide; 4) carrying out secondary heating and heat preservation; 5) cooling and discharging liquid; 6) washing with hot water; 7) washing with cold water; and 8) acid neutralization. Compared with a traditional direct heating production process, the stepped heating pretreatment process provided by the invention has the advantages that energy is saved, the production efficiency is improved, and the treated cotton fabric is good in whiteness, capillary effect and hand feeling, high in practicability, safe and environment