In organic chemistry, a class of non-aromatic compounds containing mercaptol functional groups (-SH) is called thiol. Structurally, it can be seen as the formation of oxygen in ordinary alcohols after being replaced by sulfur. With the exception of methyl thiol, which is a gas at room temperature, all other thiol is liquid or solid. Low-grade thiol generally has an unpleasant smell and is toxic. Thiol-30L two grade distillation thiol mercaptol compound, lower odor than conventional pemp thiol. It can be applied to the phenomenon of oxygen resistance polymerization which can obviously improve the low energy curing condition in the light curing system.

Oxygen resistance is mainly due to free radicals and oxygen in the system to form oxygen free radicals, the relative stability of oxygen free radicals lead to slow chain growth response, the active hydrogen in thiol can react with oxygen free radicals, thiol after the seizure of hydrogen to form a new free radicals, continue to participate in the bonus reaction. Thiol can be made by the substitution reaction of halogenated alkane and sodium hydride, and can be used as a drug, antidote and rubber vulcanization inhibitor.