What are the problems in the processing of silicone softener?

1. Decreased hydrophilicity of fabrics

Generally, it is caused by the problem of the film structure and the lack of water absorption genes after silicone oil film formation, as well as the blocking of water absorption centers such as hydroxyl groups on cellulose fibers, carboxyl groups on wool, and amino groups, which leads to decreased water absorption.

Treatment method: Anionic, non-ionic films and hydrophilic silicone oils should be used as much as possible.

2. Dark spots

Causes:

(1) The oil stains on the fabric were not completely removed during pretreatment, and the color of the oil stains was darker during dyeing.

(2) There was too much foam in the dye bath, and the mixture of foam, flower sweaters, dyes, etc. was stained on the fabric.

(3) Dark oil spots were caused by the floating oil of defoaming agent.

(4) Tar-like substances in the dye vat were stained on the fabric.

(5) Dyes agglomerated into dark spots under different circumstances.

(6) Excessive calcium and magnesium ions in the water combined with dyes to stain the fabric.

Treatment method:

(1) Add degreasing agent for refining during pretreatment.

(2) Use low-foam or non-foaming dyeing auxiliaries.

(3) Choose defoaming agents that are not easy to float oil, add chelating agents to improve water quality, and add dispersing agents to prevent dye aggregation. Use cleaning agents to clean the vat in time.

3. Light spots

Causes:

(1) Uneven pre-treatment, poor hair effect in some parts, resulting in a certain degree of dye repellency, and containing dye repellent substances. During pre-treatment, the cloth contains calcium soap, magnesium soap, etc. or uneven mercerization.

(2) Uneven drying of semi-finished products.

(3) The cloth surface is stained with undissolved solids such as sodium sulfate and soda ash.

(4) Water is dripped on the dyed material before drying.

(5) Auxiliary stains brought by the dyed material during the softening treatment and other post-finishing.

Treatment method: Strengthen pre-treatment, the pre-treatment auxiliaries must not easily form calcium and magnesium soaps, and the pre-treatment must be uniform and thorough (this is related to the selection of scouring agents, penetrants, chelating dispersants, mercerizing penetrants, etc.). Sodium sulfate, soda ash, etc. must be dissolved before entering the tank and production management must be strengthened.

4. Alkali spots

Causes: Alkali spots are caused by incomplete or uneven alkali removal after pre-treatment (such as bleaching and mercerization).

Treatment method: The alkali removal process of the pre-treatment process must be strengthened.

5. Silicone oil stains

Causes: The pH value of the cloth surface is not neutral, especially with alkali, causing silicone oil to break and float. The treatment bath water quality is too poor and the hardness is too high. Silicone oil is very easy to float in water with a hardness of >150PPM. Silicone oil quality problems include poor emulsification (poor emulsifier selection, poor emulsification process, large emulsified particles, etc.) and shear resistance. Choose silicone oil that is resistant to shear, electrolytes, and pH changes, but pay attention to the use of silicone oil and the environment, and you can also consider choosing hydrophilic silicone oil.

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