In newborn babies, salivary gland secretion is not perfect, saliva secretion is small, so generally do not drool. After 4 months, due to the addition of complementary foods, saliva secretion increased. After 6 months, the deciduous teeth began to erupt, which can stimulate the upper gingival nerve and increase the salivary gland secretion reflexively. At this time, the ability of children to swallow saliva has not yet formed, too much saliva. It will involuntarily flow out from the corner of the mouth, that is, the "drooling" that is used to speaking, especially in children aged 1 to 2 years old. The drooling of this period is a normal physiological phenomenon, parents do not have to worry about this. After the age of 2, the function of swallowing saliva in children is gradually improved, and this phenomenon will naturally disappear. The need for a waterproof saliva towel is needed before the baby's swallowing ability is still not perfect. Because saliva is acidic and contains some digestive enzymes and other substances, it has a certain stimulating effect on the skin. Therefore, for children who often drool, parents should always wipe off the saliva from their mouths, and wash them with warm water, then apply Apply grease to protect the skin of the chin and neck, and prevent the saliva from soiling the clothes. Handkerchiefs for children to brush water, soft texture, cotton gauze towel is appropriate, should be washed frequently, can not be used when wiping, gently wipe the saliva to avoid damage to local skin. But such frequent wiping is also an individual effort. The best way is to use a waterproof saliva towel, but to pick light and soft, do not put extra burden on the baby, do not use a very heavy and thick saliva towel, and the material should be safe. The saliva towel is a kind of cleaning products that are used under the chest and under the jaw when the infant, the elderly, the disabled person dine, and resemble a child's saliva pocket or bib.