摘要:
Photochromic compounds belonging to the group of spiro-isoindolino-oxazines having general formula (I). The above photochromatic compounds having general formula (I) have excellent photochromic characteristics, excellent stress resistance and high dyability characteristics.
摘要:
Stabilizing mixtures for organic polymers comprising: a) at least one compound belonging to the group of pyrazolones; b) at least one compound belonging to the group of organic phosphites or phosphonites; c) at least one compound belonging to the group of sterically hindered phenols; and d) at least one compound belonging to the group of sterically hindered amines. The above mixtures are useful in the stabilization to degradation caused by oxygen, heat and/or light, of organic polymers.
摘要:
Polymeric compositions comprising a polymer and photochromic compounds belonging to the class of spiro-pyrans, having the general formula (I): ##STR1##
摘要:
Stabilizing mixture for photochromatic substances containing a cyclic amine chosen from 1,4-diazabicyclo-(2.2.2)octane and quinuclidine, or their derivatives, and at least one sterically hindered amine.
摘要:
A method of upgrading a product containing a minor proportion of pre-vitamin d.sub.2 or pre-vitamin d.sub.3 and a major proportion of tachysterol comprising irradiating the product with laser light in the wavelength range 330-360 nanometers to obtain a product containing approximately 95% pre-vitamin -D.sub.2 or pre-vitamin -D.sub.3, and heating this product to convert the pre-vitamin -D.sub.2 or pre-vitamin -D.sub.3 to vitamin -D.sub.2 or vitamin -D.sub.3.
摘要:
A method of producing carbonyl fluoride by multiphoton decomposition of carbon dioxide-sulphur hexafluoride mixtures comprising irradiating gaseous carbon dioxide-sulphur hexafluoride mixtures in a reaction chamber at a pressure in the 10-50 Torr range with a laser beam at a frequency of about 944 wavenumbers and passing the material from the reaction chamber after irradiation through a chemical processing stage to obtain a carbonyl fluoride product.
摘要:
Process of photoetching of superficial coatings based on polymeric material comprising the irradiation of the coated surface with localized excimer laser beams having wavelengths equal to or lower than 193 nm.