Photosensitive recording materials

Triphenylmethane leuco dyes are used for photographic materials. The photographic system requires a polymer binder such as acrylic acid-methyl methacrylate copolymer115 or a copolymer of isophthalic and terephthalic acids116 a sensitizer such as 4-(4-n-amyloxyphenyl)-2,6-bis(3-ethylphenyl)-thiapyrilium perchlorate,117 a photo initiator such as hexaarylbisimi-dazole,118 and phenyl tribromomethyl sulfone, cycloalkane such as 1,2,3, 4,5-pentabromo-6-chlorocyclohexane,119 or 3-benzylidene-9-methyl-2,3-dihydro- 1 TZ-cyclopenta [b] quinoline.120 

The redox system consists of pyrene or 9,10-phenanthrene quinone as oxidant and an alkyl ester of 3,3, 3 -nitrilopropionic acid as reductant.121 This system deactivates oxidation by bisimidazole when irradiated at 380-550nm, since the quinone is reduced to hydroquinone and thus stabilizing the previously generated dye image.122,123 

Hexa(hydroxyethyl)pararosaniline nitrile has been used in a chemical radiochromic dosimeter.130 Ferricyanide oxidation of leuco Crystal Violet to Crystal Violet dye finds use in detection of various heavy metals131 at trace quantities. Oxidation of leuco triphenylmethanes by chloramine-T is catalyzed by iodide and therefore is used for detection of iodide.132 On the other hand, the inhibition of the catalytic effect of iodide by some ions can be used for determining traces of Ag(I), Hg(II), Pd(II). In addition, the triphenylmethane leuco dyes, phenolphthalein or phenol red are used extensively as indicators in calorimetric and titrimetric determinations. 

Venkataraman, K. (ed.), The Chemistry of Synthetic Dyes, Vol. 2, Academic Press, New York (1952). 

The Chemistry of Synthetic Dyes and Pigments, American Chemical Society Monograph Series, Reinhold, New York (1955). 

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Photosensitive and heat-sensitive preparations recording materials containing... 

Dextrin is extensively used in the manufacture of photosensitive materials (developers, thermal recording materials, optical information recording media, and photohardenable printing and transfers). Among other uses, dextrin diminishes the absorptivity and flabbiness of diazo copying... 

The theoretical photosensitivity limit of nonsllver organic recording materials without amplification can easily be calculated on the basis of a hypothetical model. To this purpose a simple photochemical reaction whereby a compound A gives rise to a colored species B In the Irradiated areas has to be considered ... 

Major Applications Display device, semiconductor, sensors, photosensitive materials, recording materials, imaging materials,io inks,n engraving coalings,i2 lubricants, hair dyes,i4 food storage, 15.16 dental materialsi i ... 

Photoreactive and photochromic resins are easily prepared from SMA materials. For example, coupling 4-glycidoxychalcone " and a-(4-azidophenoxy) ethanol " to SMA gives potentially useful photosensitive coatings. Covalently bound 4-aminoazobenzene derivatives are useful in reversible hologram recording materials. " ... 

Diener, G. Keil, D. Kapler, R. Opfermann, J. Hoerhold, H. H. Klee, J. Xransparent electrophotographic recording material with improved photosensitivity. Ger. (East) DD 229231, 1985 Chem. Abstr. 1986,105, 143500. 

Nowadays, polymeric photoconductors may be used in electrophotography, microfilms, photothermoplastic recording, spatial light modulators, and nonlinear elements. The combination of photosensitivity with high quality electrical and mechanical properties permits the use of such materials in optoelectronics, holography, laser recording and information processes. The applications of the various types of polymers were reported in the final parts of the relevant items in the earlier sections. Here, we will briefly analyze the common features of photoconductive polymer applications. The separate questions of each type have been dealt with in some books and papers [3, 11, 14, 329]. 

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