In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens, which are excellent in yield and quality with mitigated environmental problems by controlling the size of the diamine hydrochloride composition, the b* value according to the CIE color coordinate of the diamine hydrochloride composition, or the content of water in the diamine hydrochloride composition within a specific range.

In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens, which are excellent in yield and quality with mitigated environmental problems by controlling the size of the diamine hydrochloride composition, the b* value according to the CIE color coordinate of the diamine hydrochloride composition, or the content of water in the diamine hydrochloride composition within a specific range.

A xylylene diisocyanate composition contains a xylylene diisocyanate and a chloromethylbenzyl isocyanate. The content ratio of the chloromethylbenzyl isocyanate is 0.2 ppm or more and below 600 ppm.

The diisocyanate composition according to an embodiment of the present invention comprises, in the composition, a benzyl isocyanate having a methyl group in an amount of 5 ppm to 200 ppm, an aromatic compound having a halogen group in an amount of 5 ppm to 1,000 ppm, a benzyl isocyanate having an ethyl group in an amount of 1 ppm to 1,000 ppm, or a combination thereof. It is possible to improve the optical characteristics by preventing the occurrence of yellowing, striae, and cloudiness and to enhance the mechanical properties such as impact resistance at the same time. Thus, it can be advantageously used to prepare an optical material of high quality.

The diisocyanate composition according to an embodiment of the present invention comprises, in the composition, a benzyl isocyanate having a methyl group in an amount of 5 ppm to 200 ppm, an aromatic compound having a halogen group in an amount of 5 ppm to 1,000 ppm, a benzyl isocyanate having an ethyl group in an amount of 1 ppm to 1,000 ppm, or a combination thereof. It is possible to improve the optical characteristics by preventing the occurrence of yellowing, striae, and cloudiness and to enhance the mechanical properties such as impact resistance at the same time. Thus, it can be advantageously used to prepare an optical material of high quality.

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.

Disclosed herein are compositions and methods of making phenolic compounds and phenolic resins. The resins include multifunctional epoxies, amino glycidyl derivatives, alkanoate derivatives, alkyl ether derivatives, and multi-functional amines prepared from hydroxymethyl derivatives of novolac resin.

Disclosed herein are compositions and methods of making phenolic compounds and phenolic resins. The resins include multifunctional epoxies, amino glycidyl derivatives, alkanoate derivatives, alkyl ether derivatives, and multi-functional amines prepared from hydroxymethyl derivatives of novolac resin.

Disclosed herein are compositions and methods of making phenolic compounds and phenolic resins. The resins include multifunctional epoxies, amino glycidyl derivatives, alkanoate derivatives, alkyl ether derivatives, and multi-functional amines prepared from hydroxymethyl derivatives of novolac resin.