OPTICAL RECORDING MEDIA

W. Bas Zeper, Magneto-optical Recording Media on Co jPt Multilayers, Ph.D. dissertation. University of Twente, Enschede, the Netherlands, 1991. 

Optical recording media for read-write applications are still in the research stage. U S. companies are roughly on par with Emopean and Japanese companies in such research. Read-only applications (e g., CD-ROM disks and compact audio disks) are largely dominated by manufacturing technology from overseas. 

Much of the ground-breaking research on dyes for optical recording media was carried out in the 1970s and 1980s, and, at that time, the emphasis was on WORM media.196 There are many classes of dyes which are potentially suitable for WORM media and excellent reviews of the patent and scientific literature have been published.166,202... 

Cation-Radicals of Triarylamines in Optical-Recording Media... 

The excellent insulating and dielectric properties of BN combined with the high thermal conductivity make this material suitable for a huge variety of applications in the electronic industry [142]. BN is used as substrate for semiconductor parts, as windows in microwave apparatus, as insulator layers for MISFET semiconductors, for optical and magneto-optical recording media, and for optical disc memories. BN is often used as a boron dopant source for semiconductors. Electrochemical applications include the use as a carrier material for catalysts in fuel cells, electrodes in molten salt fuel cells, seals in batteries, and BN coated membranes in electrolysis cells for manufacture of rare earth metals [143-145]. 

The thrust of research on optical recording media is to achieve high sensitivity and long-term stability simultaneously. Since these are conflicting properties, a compromise between sensitivity and stability is usually made. In the future, the availability of visible semiconductor lasers with high output power will relax the sensitivity requirement. Finally, the recording media should require no further processing steps (Jamberdino, 1981). 

In relation to the perspective of application of photochromic quinones in optical recording media, the spectral characteristics of the photoinduced form for phenox-... 

The largest volume use of polymers in optical recording media is in the disk substrate. A schematic of a typical double-sided disk substrate is shown in Figure 1.38, which illustrates the properties required of the substrate material ... 

F.-H. Kreuzer, Ch. Brauchle, A. Miller, A. Petri, "Cyclic Liquid-Crystalline Siloxanes as Optical Recording Media", in Polymers as Electrooptical and Photooptical Active Media (Ed. V. Shibaev), Springer, Berlin, 1996, p. 111. 

More recently, in the 1980s and 1990s new series of fused phenothiazine derivatives, the benzo[a,b or c]phenothiazines (BPHTs), were synthesized [3, 21 and references therein] and have received a great deal of attention, mainly because of their potential applications and their important biomedical properties [12-24]. Indeed, some BPHTs are coloured compounds and have been applied as polycyclic dyes or pigments for synthetic polymers, and also in optical recording media ([21] and references therein). Moreover, certain benzo [a or c]phenothiazine derivatives are potential anti-helmintics, possess an antiviral activity, for example inhibiting the multiplication of encephalomyocarditis viruses in tissue cultures ([21,22], and refer-... 

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