| 摘要 |
PURPOSE: A manufacturing method of polythiol compound is provide to improve yield of a polythiol compound, to provide a clear and transparent polythiol compound for lens, to reduce manufacturing cost and maximize the quality of an optical lens. CONSTITUTION: A manufacturing method of polythiol compound uses purified thiourea in which metal content is 2 weight% or less, and calcium content is 0.95 weight% or less, and comprises a step of reducing the content of bis(2-hydroxyethyl)disulfide which is contained in 2-mercaptoethanol to 0.5 weight% or less, and hydrolyze isothiuronium salt, which is an intermediate product, to ammonia solution. The ammonia solution is ammonia solution 25% which is dissolved in water of high purity, of which content of organic material or metallic material is 2weight% or less. The polymerizable resin composition comprises the polythiol compound and a polyisocyanate compound. |
