Photochromic behaviour of surfactant spiro [2H-1-benzopyran-2,2′-[2,3]-dihydroindole]s (spiropyrans) adsorbed into clay interlayers
摘要:
Spiro[2H-1 -benzopyran-2,2'-[2,3]-dihydroindolels (abbreviated as spiropyrans) containing long omega-pyridinoalkyl chains have been intercalated into clay interlayers and studied to observe the photochromic characteristics of the resulting molecular assemblies. 1'-Octadecyl-3',3'-dimethyl-6-nitro-8-pyridinomethyl-(SP1801(+)), 1'-(10-pyridinodecyl)-3',3'-dimethyl-6-nitro- (SP10(+)00) and 1'-(10-pyridinodecyl)-3',3'-dimethyl-6-nitro-8-icosylcarbonyloxymethyl-spiropyrans (SP10(+) 22) were all quantitatively intercalated into the clay interlayer and exhibit normal photochromism in aqueous clay dispersions. Their thermal decolourations obey simple first-order kinetics and are about one-tenth as slow in clay dispersions and about one-hundredth as slow in clay films as that in bulk solution witho ut clay at 50 degrees C. However, 1',3',3 '-trimethyl-6-nitro-8-pyridinomethylspiropyran (SP0101(+)), a homologue without a long alkyl chain, exhibits inverse photochromism and its thermal decolouration undergoes two kinds of first-order kinetics in aqueous clay dispersions. These results are explicable in terms of the restricted conformational motions of the intercalated spiropyrans.
A method for preparing a photochromic material is provided. The photochromic material is a spiropyran compound with a nitro group at the 5′ position and a long-chain alkyl group at the 1′ position. Since a nitro group is present in the compound obtained by the present method, the colored form of the compound possesses absorption sensitivity in the wavelength region of a semiconductor laser beam. Moreover, the photochromic reactions of the compound are of high stability. Furthermore, since the compound possess a long-chain substituent at the 1′ position, ultrathin films of extremely high uniformity can be formed from the compound by the Langmuir-Blodgett method.
A photochromic material and an optical storage medium using the same
申请人:MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
公开号:EP0483542A1
公开(公告)日:1992-05-06
The present invention provides a photochromic material which comprises a spiropyran compound of formula (I):
wherein R¹ and R² are independently alkyl groups each containing 1 to 30 carbon atoms and Y is a halogen.
The photochromic material possesses absorption sensitivity at wavelengths in the length region of about 700 nm which is the oscillation range of a semiconductor laser device, and possesses higher stability compared with conventional one when it becomes a colored form.
Ionic spiropyran compound and photochromic material conjugated it with clay
申请人:NISSHO IWAI BENTONITE CO.,LTD.
公开号:EP0738728A2
公开(公告)日:1996-10-23
Present invention provides an ionic spiropyran compounds having a long-chain alkyl group or groups at both or either of the 1- and 2-positions of 3',3'-dimethyl-6-nitrospiro[2H-1-benzopyran-2',2'-indol composite material conjugated the said ionic spiropyran compound with clay mineral.
Said composite material is capable of forming a transparent thin film photo-interconvertible between the said spiropyran structure and the corresponding merocyanine structure.