Abstract: Provided are an isocyanate composition, a modified isocyanate, a polyurethane resin, and optical materials, and an effective factor of the isocyanate composition is 3.90 to 5.70. By the design and control of effective factor, the isocyanate composition has excellent reactivity and can be used for the preparation of high-performance resins such as polyurethane and polythiourethane without causing undesirable phenomena such as gelation during polymerization. In addition, the isocyanate composition can effectively improve the yellowing resistance, stability and optical performance of polyurethane, polythiourethane and other products, so that the obtained polyurethane and polythiourethane will not exhibit white turbidity and opacity phenomena. The optical material prepared with the isocyanate composition has remarkably reduced yellowness index and remarkably reduced optical deformation occurrence rate, thereby effectively improving the optical properties of the optical material.

Abstract: Disclosed is a 1,3-bisisocyanatomethylcyclohexane composition and an optical resin prepared therefrom. The composition comprises, based on the weight of 1,3-bisisocyanatomethylcyclohexane, a) 65%-95 wt % of trans-1,3-bisisocyanatomethylcyclohexane; b) greater than 0 and less than or equal to 0.5 wt %, preferably 0.02-0.5 wt % of 1,4-bisisocyanatomethylcyclohexane. Preferably, the 1,3-bisisocyanatomethylcyclohexane composition contains greater than 0 and less than or equal to 600 ppm of 1-isocyanatomethyl-3-methylcyclohexane, based on the weight of 1,3-bisisocyanatomethylcyclohexane. The 1,3-bisisocyanatomethylcyclohexane composition is used for preparing an optical resin, which can be applied to produce an optical lens with a better performance in preventing opacification and optical distortion.

Abstract: Preparation method for a polyurethane optical resin and applications thereof. The preparation method for the polyurethane optical resin comprises: a raw material composition comprising isocyanate and a polythiol compound undergoes a polymerization to produce the polyurethane optical resin. The turbidity value of the isocyanate used in the raw material composition is controlled at ?2 NTU. The polyurethane optical resin produced is applicable in manufacturing optical products.

Abstract: A xylylene diisocynate composition, a preparation method therefor and the use thereof. The xylylene diisocynate composition includes xylylene diisocynate and 0.2-500 ppm of a compound represented by formula (1). A resin prepared from the provided xylylene diisocynate composition has an excellent discoloration resistance and can effectively inhibit yellowing and/or white turbidity thereof.

Abstract: Disclosed is a 1,3-bisisocyanatomethylcyclohexane composition and an optical resin prepared therefrom. The composition comprises, based on the weight of 1,3-bisisocyanatomethylcyclohexane, a) 65%-95 wt % of trans-1,3-bisisocyanatomethylcyclohexane; b) greater than 0 and less than or equal to 0.5 wt %, preferably 0.02-0.5 wt % of 1,4-bisisocyanatomethylcyclohexane. Preferably, the 1,3-bisisocyanatomethylcyclohexane composition contains greater than 0 and less than or equal to 600 ppm of 1-isocyanatomethyl-3-methylcyclohexane, based on the weight of 1,3-bisisocyanatomethylcyclohexane. The 1,3-bisisocyanatomethylcyclohexane composition is used for preparing an optical resin, which can be applied to produce an optical lens with a better performance in preventing opacification and optical distortion.

Abstract: Preparation method for a polyurethane optical resin and applications thereof. The preparation method for the polyurethane optical resin comprises: a raw material composition comprising isocyanate and a polythiol compound undergoes a polymerization to produce the polyurethane optical resin. The turbidity value of the isocyanate used in the raw material composition is controlled at ?2 NTU. The polyurethane optical resin produced is applicable in manufacturing optical products.