1. When washing hotel tablecloths, the general view is that it must be washed under high temperature (80-90°C) and high alkali (washing liquid pH value > 12). The effect of grease is undeniable. But from the perspective of saponified grease, it is also believed that high alkalinity can saponify grease and be eluted, which leads detergent factories to add a large amount of caustic soda when preparing strong washing powder, some reaching 60%, in order to keep the washing liquid High pH. In order to maintain the high alkalinity of the washing liquid, when the caustic soda content in the strong washing powder is low, increase the amount of strong washing powder or add super strong synthetic alkali during the main wash. In view of the damage of high alkalinity to the fiber, it is not conducive to the maintenance of fabrics . For this reason, the author has developed a tablecloth washing powder with moderate alkalinity. Under the same conditions as the strong washing powder, the pH value of the washing liquid is only 9-10, which can also clean the tablecloth, and the backwashing rate has always been lower than 2%, which shows that tablecloth washing does not necessarily have to maintain high alkalinity. This new detergent powder does not need to add emulsifier when washing cotton tablecloth, and only needs to add less emulsifier than normal amount when washing yarn tablecloth, which can reduce the cost of users, and this detergent powder is also used for Washing towels and bed sheets are very popular among users.
2. When we combine the main washing and bleaching into one step, we also add chlorine bleaching powder during the main washing, that is, washing and bleaching are carried out at the same time, and it is found that the oil removal effect is better. The facilitative effect of chlorine bleach on oil removal is yet to be studied.
3. Washing tablecloths in cold water without heating can save energy consumption. It is a relatively fashionable concept at present, and it is also a question worthy of serious discussion. We found it to be somewhat effective on new grease stains, but at a higher user cost, and cold water washes performed poorly on greasy tablecloths that had been stored for a day or more. For the oil stains that have been stored for more than one day, we temporarily call them old oil stains. Old oil stains may even become rancid and emit a hala oily smell. This kind of tablecloth is difficult to clean. If you observe it in the sun, you can see pieces on the tablecloth fiber. Black-gray stains stained with oil stains, which are oil stains immersed in the fiber, can only be cleaned with special methods.