Display device characteristics

Mullen and coworkers have prepared a polymer 129 with a first-generation polyphenylene dendron on the side chain (Scheme 60) [228]. Unlike Fr chet dendrimers, such dendrimers are rigid and shape-persistent. Interestingly, the bulky side chains produced no blue shift in the absorption or emission of the polymer compared with PDAFs such as 89, indicating that there is no increased steric repulsion between adjacent fluorene units. LEDs using this polymer display device characteristics (turn-on voltage, emission efficiency. 

Electronic and Electrical Applications. Sulfolane has been tested quite extensively as the solvent in batteries (qv), particularly for lithium batteries. This is because of its high dielectric constant, low volatUity, exceUent solubilizing characteristics, and aprotic nature. These batteries usuaUy consist of anode, cathode polymeric material, aprotic solvent (sulfolane), and ionizable salt (145—156). Sulfolane has also been patented for use in a wide variety of other electronic and electrical appHcations, eg, as a coil-insulating component, solvent in electronic display devices, as capacitor impregnants, and as a solvent in electroplating baths (157—161). 

In these polymeric species, the M,AT2-1,2,4-triazole linkage is rigid, and allows an efficient transmission of cooperative effects. Consequently, abrupt ST with broad thermal hysteresis loops have been observed [26, 32-34]. The absorption spectra of these compounds show a broad band at 520 nm corresponding to the Aig Trg d-d transition in the LS state whereas no band is found in the visible region in the HS state, the 5T2g-5Eg transition being located around 850 nm [7a]. The ST is thus accompanied by a thermochromic effect, purple (LS) and white (HS). These characteristics make these compounds potential candidates for practical applications, e.g. thermal display devices [7, 8, 17]. Such behaviour has been observed, for example, in the compound [Fe(4-amino-l,2,4-triazole)3](NC>3)2 [32] whose SCO is associated with a hysteresis loop of width 35 K, centred above room temperature [8]. 

In recent times, many if not most biological materials have been recognized as liquid crystals. In the consumer electronics area, nearly every item sold incorporates a liquid crystal display device. The liquid crystalline state of matter exhibits characteristics not found anywhere else in science and engineering. The important and relevant characteristics include ... 

ICP thin films were used as driving electrodes for polymer-Dispersed Liquid-Crystals (PDLC) display devices. Liquid-crystalline-based display devices, which are commonly made of a liquid-crystal compound sandwiched between two substrates coated with a conducting layer of indium tin oxide (ITO), whose substitution with ICP electrodes could improve the optical and mechanical properties of the display devices. On the way to all-organic displays, PDLC sandwiched between two plastic substrates coated with ICP layers are promising devices for paper-like displays for electronic books which require flexibility, lightness, and low-power consumption. The electro-optical characteristics (transmission properties, drive voltages and switching times) of the PDLC devices depend on the nature of the ICP substrate used [13]. 

In addition to the characterization of polymers and liquid crystals, AW devices have been used in the characterization of layered metal films, especially superlattices [237-239]. Metal superlattice structures are of interest because they display interesting characteristics including, in some cases, superconductive properties. Superlattice metal films can exhibit a supermodulus effect (i.e., an increase in the Young s and torsional modulus) or an anomalous softening ( 35%)... 

Typical of polymer conductors, these PEDOT-PSS electrodes exhibit an electrical conductivity of around 0.1 S/cm [11], A uniform, continuous pentacene (p-type organic semiconductor) layer is then deposited on the PEDOT-PSS source and drain electrodes to complete the bottom-contact OTFTs. Since pentacene is deposited in the final step, it is not exposed to any of the solvents (e.g., acetone) required to prepattem the PEDOT-PSS electrodes. These bottom-contact pentacene TFTs with PEDOT-PSS electrodes exhibit charge-carrier mobilities comparable to charge-carrier mobilities of typical bottom-contact pentacene TFTs with gold electrodes (0.2 cmWs) [1] and on/off current ratios as high as 10 . Eurther, these device characteristics are on par with requirements for driving most display applications [12,13]. 

The compounds which first found applications in display devices were the 4-alkyl-4 -cyanobiphenyls 17 and the 4-alkoxy-4 -cyanobiphenyls 18 (Gray and colleagues, 1973) . It has subsequently proved possible to incorporate other structural features and thereby modify the liquid crystal characteristics in interesting and sometimes useful ways. For... 

Display devices WO3. Pb(LaTip, ITO High contrast images relatively good fatigue characteristics... 

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