Silk is always seen as the nobility of the fabrics because of its unique natural luster and comfortable wearing experience. However, silk is also a delicate fabric. When silk clothes accidentally come into contact with strong alkaline liquids like 84 disinfectant (a sodium hypochlorite-based cleaning agent widely used in China) and bleach, whose main component is sodium hypochlorite, they may develop a “yellowing due to alkaline damage” effect. When facing this phenomenon, how should laundry do to solve the problem?
Analysis of Causes
- Strong Alkalinity
Products like 84 disinfectants have excessively strong alkalinity. (extremely high pH value). The main component of silk fibers is silk fibroin. In a strong alkaline environment, it undergoes hydrolysis reactions, leading to the destruction of the fiber structure and a decrease in strength. At the same time, it is accompanied by color changes, presenting uneven yellow or yellowish-brown patches.
- Dual harm of Sodium Hypochlorite:
Apart from alkaline corrosion, sodium hypochlorite itself is a strong oxidant. It may lead to: Fading and local whitening.
Restoration Methods
When restoring silk clothes that have been yellowed due to 84 disinfectant, it is necessary to neutralize the residual alkalinity and chlorine, remove yellow stains, and restore whiteness or color as the situation requires. Before the operation, a small-scale test in hidden areas of the clothing (such as the inner side of the seam) should be done to ensure that no secondary damage will be caused to the clothes.
- Step 1
Prepare enough clean water → add 10-20g neutralizing acid → immerse the yellow clothes caused by 84 disinfectant in the neutralizing acid solution for 5 minutes→ gently stir to ensure the solution evenly touches all areas, especially the stains.
This step can effectively neutralize the residual alkaline substance and remove harmful chloride ions (dechlorination). After completion, take out the clothes, rinse them completely with plenty of clean water, and remove the water by squeezing instead of twisting and wringing.
- Step 2
Clothes after the first step of neutralization, dechlorination, and rinsing are still wet.
On the obvious burnt yellow patches, directly apply the medicine for removing the yellow patches with a cotton swab or a small brush → ensure that the medicine liquid fully penetrates the yellow patch area, but avoid excessive spread to the unyellowed parts. → stand still and wait → closely observe the changes of the stains.
A slight yellowing usually shows significant fading or even complete disappearance within a few minutes to tens of minutes after dot application. Moderate yellowing may take longer (30 minutes or more), and you need to wait patiently for the pigment to decompose. If the yellow stains are significantly lightened or disappear, the next step of rinsing can be carried out.
If the yellow stains still cannot be removed after waiting for a sufficient period of time, the area that has been treated with the liquid medicine should also be thoroughly rinsed off with clean water.
- Step 3
Prepare warm water at around 40℃ → the water volume should also be sufficient to submerge the clothes →add bleach suitable for mulberry and ginseng threads to water, following the proportion specified in the product instructions. (Do not increase or decrease the dosage at will.) → Add wool and silk shrink-proof agent, which can protect silk fibers from damage during the oxidation and bleaching process and maintain their flexibility → Immerse the clothes in the prepared solution → Gently and continuously turn the clothes to ensure the solution acts evenly → Closely observe the changes. This process may only take a few minutes or even ten to twenty minutes. Do not soak for a long time. → Once the yellow stains disappear or a satisfactory effect is achieved, immediately take it out and then rinse repeatedly with a large amount of clean water to remove the remaining bleach as thoroughly as possible.
- Step 4
This step is mainly for neutralizing alkaline residue and preserving the softness of the silk.
Prepare enough clean water → add wool and silk shrink-proof agent → immerse the clothes after complete rinses in this solution for 5 minutes→ take it out directly after soaking without rinsing.
- Step 5
Wrap the clothes in the big clean towels and remove additional water content by gently squeezing instead of twisting and wringing. After adjusting the clothes, you should hang them in a cool and well-ventilated place to dry naturally, avoiding direct sunlight. After the complete drying, low-temperature ironing can be done. (use a cloth as a pad and select the silk setting).
Important Supplements and Precautions
In the early stage of communication with the customers, laundry shops should inform the clients early that this kind of damage may not be completely restored, and they can only try their best to restore it. If the injury lasts for a long time and covers a large area, it may be necessary to send it to a professional institution for recovery.
Laundry shops should not pursue the complete recovery of the damage when handling this kind of clothes. When the current methods cannot restore the clothes, they should stop in time to avoid secondary damage to the clothes.
All in all, damage to silk clothes caused by chemicals like 84 disinfectant can be rather troublesome, but it is not completely irreversible. Understanding the causes and following the scientific process of “neutralization – dechlorination – de-yellowing – bleaching – over-acidification – maintenance” can, to some extent, save damaged clothes.
