An embodiment relates to an isocyanate composition with improved stability and reactivity and a plastic optical lens using the same. The isocyanate composition has improved stability since the content of chlorine in the composition is adjusted to 22-500 ppm, and thus the isocyanate composition can prevent the deterioration in reactivity even in the long-term storage. Therefore, the isocyanate composition according to an example, even when used after long-term storage after preparation, can be prepared, through polymerization with a thiol-based compound, as a polythiourethane-based optical material with excellent physical properties, such as refractive index, Abbe number, transparency, glass transition temperature, and yellowness, and thus the isocyanate composition is useful in fields of glass lenses, a camera lens, and the like.

The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100° C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160° C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.

The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100° C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160° C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.

The invention relates to a novel method for preparing carbodiimides.

Disclosed is a light colored modified isocyanate mixture and a preparation method thereof. The method comprises the following steps: a) reacting isocyanate groups of a raw material isocyanate under the action of a phospholenecatalyst, and finally obtaining a modified isocyanate reaction solution containing carbodiimide and/or uretonimine derivatives; and b) adding a compounded terminator of a halosilane organic and a sulfonic anhydride to the reaction solution obtained in step a so as to terminate the reaction of carbodiimidization. The modified isocyanate prepared by the method has the characteristics of a liquid state at room temperature, being stable in storage at room temperature and high temperature, and low color number.

Disclosed is a light colored modified isocyanate mixture and a preparation method thereof. The method comprises the following steps: a) reacting isocyanate groups of a raw material isocyanate under the action of a phospholenecatalyst, and finally obtaining a modified isocyanate reaction solution containing carbodiimide and/or uretonimine derivatives; and b) adding a compounded terminator of a halosilane organic and a sulfonic anhydride to the reaction solution obtained in step a so as to terminate the reaction of carbodiimidization. The modified isocyanate prepared by the method has the characteristics of a liquid state at room temperature, being stable in storage at room temperature and high temperature, and low color number.

The xylylene diisocyanate composition according to the embodiments has a chlorine content of 100 to 1,000 ppm to improve the stability, so that the degradation of the reactivity can be prevented even when it is stored for a long period of time. Therefore, even if the xylylene diisocyanate composition according to the embodiments is used after it has been stored for a long period of time for sale or the like, the xylylene diisocyanate composition can be polymerized with a thiol to produce a polythiourethane-based optical material having excellent properties such as refractive index, Abbe number, transparency, glass transition temperature, yellowness index, and the like. Therefore, it can be advantageously used in the field of eyeglass lenses, camera lenses, and the like.

The xylylene diisocyanate composition according to the embodiments has a chlorine content of 100 to 1,000 ppm to improve the stability, so that the degradation of the reactivity can be prevented even when it is stored for a long period of time. Therefore, even if the xylylene diisocyanate composition according to the embodiments is used after it has been stored for a long period of time for sale or the like, the xylylene diisocyanate composition can be polymerized with a thiol to produce a polythiourethane-based optical material having excellent properties such as refractive index, Abbe number, transparency, glass transition temperature, yellowness index, and the like. Therefore, it can be advantageously used in the field of eyeglass lenses, camera lenses, and the like.

The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100 C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160 C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.

The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100 C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160 C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.