Toothpaste is comprised of powder abrasivus, wetting agent, surfactant, adhesive, spices, edulcorant and other special ingredient.
The commonly used abrasives in tooth paste include:
① Calcium carbonate: calcium carbonate is classified into being heavy and light, among which the ground limestone is made by smashing, grinding and refining limestone and calcite while the latter is produced by putting calcium salt into hydrochloric acid and after that it will go through carbon dioxide to have precipitation of calcium carbonate. The light calcium carbonate features small particles and light weight, which can be used for tooth paste.
② Calcium hydrogen phosphate( Calcium hydrogen phosphate dihydrate CaHPO4・2H2O and Calcium hydrogen phosphate anhydrous salt CaHPO4): calcium hydrogen phosphate has dihydrate salt and anhydrous salt of dimolecular water. Dyhydrate salt can be mixed up with other ingredient well. However, as anhydrous salt has high hardness and strong friction, 5%-10% of dyhydrate salt can be added into anhydrous salt when toothpaste is manufactured for a special purpose.
③Calcium orthophosphate(Ca2P2O7): calcium orthophosphate is attained through high-temperature processing. Because it will not react with fluorochemical, it is a base for making toothpaste with fluoride.
④ Calcium silicate hydrate(SiO2・nH2O): calcium silicate hydrate is extreme tiny white particles, which can be applied in transparent toothpaste. In addition, it can be bulking material and tackifier for toothpaste owing to its large specific volume.
⑤ Calmogastrin[A1(OH)3]: its particles are rather thicker but it will not damage enamel but increase the radiance of toothpaste; also, it performs well when cleaning the teeth.
Wetter is able to stop toothpaste from solidifying to be hard in the hose and make the paste glossy. The wetters in toothpaste include glycerol, propanediol and sorbital, etc.
Neutral detergent named sodium lauryl alcohol sulfonate is extensively applied at present in order to clean the dirt in the mouth. It can be foaming quickly and clean the dirt in the mouth as well. The purity of surfactant used in toothpaste is highly required which can not contain peculiar smell with the dosage of 2% generally.
Adhesive can be used for dispersing the ingredients evenly in toothpaste, such as cMc and its derivatives, carageen and algin.
The main spice in toothpaste is mint which is dispensable for providing a sense of coolness for toothpaste. Pennyroyal can be divided into various materials like menthol( methol), menthene and mint as well as the spices derived from it. Besides, fruit flavors can be used including citrus spices. However, they are strictly controlled as for the spices for toothpaste.
A small amount of saccharin can be put into toothpaste so as to improve the mouth feel. The dosage of saccharin is 0.01% to 0.1% in general because the glycerol used as wetter tastes sweet. Also, xylosic alcohol can acts as edulcorant.
7. Other special ingredients
With the purpose of cure oral diseases, some toothpaste will have special ingredients: ① bactericides like dioxophenyl diguanidinyl hexane and cypress alcohol can be added so as to remove halitosis and copper chlorophyllin is efficient in preventing halitosis in some extent. ② fluoride is able to prevent from caries, which can not only inhibit the fermentation of residues in the mouth but strengthens enamel on the surface of teeth. With respect to safety, the fluoride content in toothpaste should be below 1000mcg as regulated. The incidence of a disease among people who drink natural water containing fluoride is relatively low; otherwise, the surface of teeth becomes white and turbid(porphyritic) so that the dentinum goes bad. Moreover, a certain amount of preservative should be put into the toothpaste in case that the paste deteriorate.