NMR proofs of the involvement of an allenyl-naphthol as a key-intermediate in the photochromic process of [3H]-naphthopyrans
摘要:
The NMR characterization of an intermediate, proved to be involved in the photochromic process of fluoro-substituted-3,3-diphenyl-3H-naphtho[2,1-b]pyrans is reported. An o-allenyl-naphthol structure was deduced and a plausible reaction mechanism was proposed. (C) 3002 Elsevier Science Ltd. All rights reserved.
Die vorliegende Erfindung betrifft einen photochromen Kunststoffgegenstand, der ein transparentes Kunststoffmaterial und darin eingebracht mindestens einen photochromen Farbstoff umfasst, wobei mindestens das photochrome Reaktionszentrum des photochromen Farbstoffs von einer Schutzhülle auf Basis einer supramolekularen Struktur umgeben ist.
A photochromic plastic object made of a transparent synthetic resin material composed of at least two mutually penetrating polymer networks of different polymer materials and containing at least one photochromic dye homogeneously distributed therein, and a method for producing such a photochromic object.
Photochromic articles with reduced temperature dependency and methods for preparation
申请人:——
公开号:US20040191520A1
公开(公告)日:2004-09-30
Described are photochromic articles that include a substrate and at least one photochromic material adopted to change from an unactivated form to an activated form upon exposure to actinic radiation. The activated form of the photochromic material changes from more absorbing to less absorbing of radiation in the absorption region of its unactivated form as the temperature increases from 10° C. to 35° C. The photochromic article demonstrates a more consistent photochromic response, for example, an optical density response loss of 50 percent or less over a temperature range of from 10° C. to 35° C. as measured in the Photochromic Temperature Dependence Test. Methods for producing the aforedescribed articles are also disclosed.
The complete assignment of the H-1, C-13 and F-19 NMR spectra of eight fluoro-substituted 3H-naphthopyrans was achieved by the concerted application of homonuclear (H-1-H-1) and heteronuclear (C-13-H-1 and F-19-H-1) correlations. Copyright (C) 1999 John Wiley & Sons, Ltd.