There are too many types of oil stains, such as oil from hot pot, oil secreted by the skin, soy sauce spilled on clothes, etc. Different stains require different methods to clean.
For specific washing methods, please refer to this table (recommended to collect)
1. The principle of washing clothes (not simple)
The essence of washing clothes is actually the process of wetting, emulsifying and dispersing stains
Yes Most stains are water-soluble, such as sweat and sugar stains. Once they stain your clothes, wash them with water and remove them.
The vast majority of stains that are difficult to remove are fat-soluble, that is, water cannot wet and dissolve them, such as sebum, edible oil, and cosmetic oil, so surfactants (laundry detergent) are needed. Or organic solvent (dry cleaning) can be used to clean it.
Of course, some are solid particles, such as dust, iron powder, and soot. These are neither water-soluble nor organic solvent-soluble, and more rely on surfactants in laundry detergent. Dispersion, re-adsorbing it from the clothing fibers into the water.
2. How stains stain on clothes
In fact, there are 4 ways of staining, 1. The stain is at the intersection of warp and weft of the fabric → 2. The stain is wrapped by the yarn → 3. The stain penetrates into a single fiber → 4. The stain penetrates into the amorphous zone (corresponding to the regular crystalline zone) inside the fiber polymer structure .
In fact, the more difficult it is to remove, the smaller the molecular structure of the stain and the better the compatibility with the fiber. The easier it is to penetrate deeper into textiles, the harder it is to clean. For example, the fabric structure of winter down jackets is mostly made of chemical fibers such as polyester and nylon. In order to prevent wind and diamonds, the fabric density is also high, and stains such as grease (sebum on collars and cuffs) are closely combined with hydrophobic chemical fibers. Therefore, down jackets in winter are easy to get dirty and difficult to clean.
Of course, it is not only related to stains, but also closely related to the time the stains remain on the clothes. Wash a piece of clothing as soon as it gets dirty. The stains have not penetrated into the interior of the textile. If it takes a long time, After cleaning, the stains are firmly rooted in the deep parts of the clothes. Coupled with the oxidation of air, they slowly become stubborn stains that oil and water cannot enter.
No matter how you wash such clothes, there will be yellow and gray stains remaining on the clothes.
