Silicone oil softener is a type of softener widely used, with good performance and outstanding effects on textiles. However, due to improper handling, it often causes oil stains and color spots on the fabric. In severe cases, dyeing it black can reflect obvious color spots.

Many dyeing factories have to settle for second best, preferring to give up excellent hand feel finishing effects and choose low-quality fat based non silicone softeners, but they are troubled by the inability to meet customer requirements for hand feel. Therefore, solving the problem of silicon spots on fabrics after finishing with organic silicon softeners is very meaningful.

To prevent the occurrence of silicone oil stains, the selected soft finishing can be optimized from the following aspects:

1. Pre use inspection: Conduct alkali resistance, fluorescent whitening agent resistance, shear resistance, and high temperature resistance tests, and eliminate those that do not meet the requirements;

2. Control the quality of the fabric surface: Strengthen dyeing and washing to ensure that there are no anionic additives or dye residues on the fabric surface and cylinder wall, and the pH value of the fabric surface is 5.5-6.8;

3. Scientific materials: Adjust the pH value of the solution to 5-6, use water at a temperature below 40 ℃, and prohibit long-term stirring. Do not add silicone oil when the temperature in the cylinder is above 60 ℃;

4. Choose hot air drying: After dipping and rolling the softener, non-contact hot air drying should be used instead of contact drying with a drying cylinder. If using a drying cylinder for drying, a layer of cloth should be wrapped on top of the first four drying cylinders to reduce the temperature of the drying cylinder and avoid the cloth surface from quickly touching the drying cylinder and causing stains;

5. Not used in the same bath with paint: When adding paint for color correction, non-ionic softeners should be used, and the paint should be fully dissolved; If adhesive is added, compatibility with organosilicon must be considered, otherwise it can easily cause roller sticking.

Solution for encountering silicon spots:

1. Washing of organic silicon oil stains

There are many reasons for the formation of oil stains on fabrics, and the ones that are difficult to wash are organic silicon oil stains, especially when the silicone oil has reacted with the fabric, making the possibility of cleaning extremely small. (Solvent based degreaser) has a good cleaning effect on silicone oil stains. Simply apply it to the oil stains and brush it lightly. Except for slight marks on pure cotton white fabrics, it can achieve the effect of leaving no marks on various other fabrics.

2. Selection of dyeing temperature for repair

Organic silicone oil lotion itself is metastable, which is generally more stable at room temperature than at high temperature. Organic silicon on fabrics can be divided into two parts, one part has been combined with the fabric or formed into a continuous mesh film; The other part still exists in the form of free polydimethylsiloxane. Due to the destruction of the dispersion system after drying, if it is separated from the upstream of the fabric and re immersed in water, it will quickly aggregate into larger oil droplets, which will then be adsorbed onto the fabric, causing a large number of oil spots to form on the fabric. If a suitable surfactant is used to emulsify the eluted silicone oil, it will not adsorb onto the fabric and can be removed from the washing system after washing. Due to the emulsification temperature of methyl silicone oil being around 50 ℃, it is advisable to wash it at a temperature of 45 ℃± 5 ℃. Organic silicon, which forms a network structure on fabrics, is insoluble in water even at high temperatures.

3. Selection of washing emulsifiers

Part of the organic silicon polymer that does not bind to the fabric during washing is prone to coalescence into oil stains. It is necessary to choose a low HLB value lipophilic emulsifier to dissolve these oil stains. On the other hand, the washed silicone oil needs to be quickly emulsified and dispersed to be removed from the washing water system, so it is necessary to use hydrophilic emulsifiers with high HLB values, that is, to choose a combination of hydrophilic and oleophilic emulsifiers.

4. Selection of pH value

The widely used amino silicone oil, epoxy modified silicone oil, etc. can partially turn into soluble silicone oil under acidic conditions, which is convenient for dispersion and washing. Therefore, the washing solution should be adjusted to pH 5-6 with acid.