The formation of silicone oil spot
1. Alkalinity problem

Cotton fabric pretreatment is usually treated with a higher concentration of alkali to remove fabric impurities (especially the amount of mercerizing alkali), alkali into the fiber is not easy to wash, dyeing (reactive reductive dye) also to add alkali, so after finishing the cloth surface may be alkaline.

The chemical fiber fabric must be cleaned after dyeing. At present, the printing and dyeing factory is still using insurance powder and caustic soda cleaning. If the back cleaning is not clean, it will also cause the soft cloth surface with alkali. And ordinary silicone oil is not alkali resistant, under alkaline conditions will demulsification, this is the factory in the soft dip rolling through thousands of meters after the occurrence of sticky roller. Therefore, the soft cloth must be washed before alkali agent or acetic acid in the working liquid, maintain the rolling groove PH5-6.

2. Cohesion problem

On contain short fiber fabric (cotton, T/R fabric, velvet class), inevitably there will be some in the process of machining staple fell off, cloth fell from the staple accumulated in the groove, and common cohesive silicone oil, as the finishing liquid uplink to roll, and squeezed the silicone oil emulsion breaking the stick together, forming roll coating or silicone. When the water quality is poor, it will condense with ordinary silicone oil to produce sticky rolls. In addition, there will be a similar situation for lint fabric. Do a good job of cleaning before driving, and clean the hair at any time.

3. Charge stability

Cotton dyes, whitening agents are mostly anionic, and cotton whitening is basically completed in the molding machine. Additional dyeing cloth when light is wrong need to fine tune the color, repairing color usually when the soft finishing agent on the additional small dye or paint, and factories use normal general silicone oil (weak cationic) will produce charge attract reaction of Yin and Yang, cause condensation and sticky roller, and anion silicone oil feel softness and can not meet the requirements, cause confusion of the factory. Charge consistency must be considered in processing.

4. Temperature problem

Cotton long car dyeing the cloth through drying drum drying, large package or heap in cloth box, if not fully cooling, especially in large volumes cloth, in the soft fabric surface temperature may be higher, the cause of groove working liquid temperature (especially in summer), sometimes to 60 ℃ above, and ordinary silicone oil can cause sticking when heat resistance is not good.

It is better that the temperature in the rolling groove does not exceed 40 ℃.

5. Finalize the speed problem

When the factory is making some thin fabrics, the speed of shaping is very fast, sometimes up to 60 meters/min. Due to the poor permeability of ordinary silicone oil, the silicone oil will flow back on the roller, resulting in sticky roller. Pay attention to replace the working liquid in the rolling groove, and wipe the roll frequently.

6. The problem of soaking the cylinder

Many factories in the soft impregnation, ordinary silicone oil will stick to the cylinder wall, over time, the cylinder wall will form some black oil spots, stained to the cloth surface to form silicone oil spots. Strengthen cleaning work.

7. Hand feeling problem

Because now the market to fabric feel demand is higher and higher, and all kinds of fabrics due to different seasons, customer requirements are different, need to show a variety of different style requirements, there are requirements for smooth drape, smooth and flexible, fluffy soft, simple elastic and so on. One type of silicone oil usually only reflects one style. As a result, many factories need to use many kinds of silicone oil, resulting in relatively chaotic production. Sometimes, they can't find silicone oil suitable for customers, so they have to give up their business, resulting in losses. We can choose different amino-silicone oil end groups with different ammonia values to control the molecular weight and molecular distribution to synthesize amino-silicone oil with different ammonia values, viscosity and reactions to meet the requirements of various fibers in terms of softness, smoothness and elasticity.

8. Cost

At present, the biggest perplexing problem for printing and dyeing factories is the cost problem. Due to the rising prices of water, electricity and steam, while the printing and dyeing processing fee is decreasing, many printing and dyeing factories are busy for a year, but their profits are basically no. Therefore, cost control is the problem to be solved by printing and dyeing factories.

Removal of silicone oil spots

1. The fabric has not been shaped at high temperature

① Acetic acid washing

② Solvent type degreaser high temperature treatment.