Patents photosensitization

The photostability of raw and cured rubbers depends not so much on their nature as on the optical properties of the ingredients and impurities that they contain. Many ingredients of polymers, including the antioxidants used at the present time, are latent or patent photosensitizers. ... 

Photochemistry, photophysical properties and photosensitization of 7 were investigated (99MI37, 99MI42, 99MI64, 01MI23). Preparation and usage of nitrate salt of 7 were patented (01MIP14). 

Photosensitive functions are in many cases also heat sensitive, so the preparation of photosensitive polyimides needs smooth conditions for the condensations and imidization reactions. Some chemical reactants, which can be used for polyamide preparation, have been patented for the synthesis of polyimides and polyimide precursors. For example, chemical imidization takes place at room temperature by using phosphonic derivative of a thiabenzothiazoline.102 A mixture of N -hydroxybenzotriazole and dicyclohexylcarbodiimide allows the room temperature condensation of diacid di(photosensitive) ester with a diamine.103 Dimethyl-2-chloro-imidazolinium chloride (Fig. 5.25) has been patented for the cyclization of a maleamic acid in toluene at 90°C.104 The chemistry of imidazolide has been recently investigated for the synthesis of polyimide precursor.105 As shown in Fig. 5.26, a secondary amine reacts with a dianhydride giving meta- and para-diamide diacid. The carbonyldiimidazole... 

Oxadiazole derivatives have been tested in the textile industry as antistatic agents for textile finishes,232,233 thermally stable polymers,82, 234,235 fluorescent whiteners,236 oil and water repellents on cotton and wool,237 and blue dyes for polyesters and polyamides.238 Oxadiazole merocyanine dyes have been patented as photosensitizers for silver halide emulsions.239... 

Compounds of Te11, such as the dithiocarbamate (106), can be used in combination with a reducing agent in a photothermographic system that incorporates benzenetricarbonylchromium as the photosensitive component.220 Other ways of initiating the thermographic decomposition of the dithiocarbamates include the photogeneration of catalysts such as Ag° and Pd° these are described in several patents.221... 

Liu, R. (1998). Methods of making liposomes containing hydro-monobenzoporphyrin photosensitizer. QLT Photo Therapeutics, US Patent 5,707,608. 

U.S. Patent 3,390,996 Photosensitive composition comprising an organic nitrogen-containing color-generator, a photo-oxidant and a redox couple A. 

Universal product code marking composition containing a photosensitive dye former, a pigment and a binder. Dessauer, Rolf (du Pont de Nemours, E. I., and Co.) U.S. Patent 4,029,506 (Cl. 96-48R G03C5/24), 14 Jun 1977, Appl. 516,483,... 

This Report follows the format of the previous one except that, commencing this year, the patents section will be omitted. Academic and industrial research in this field continues to be prolific, particularly in areas of photopolymerization such as electron beam curing and photoresists. Other areas, such as the photosensitized degradation of polymers for producing photodegradable plastics, have diminished to only a few articles, and consequently these will now be included in the section dealing with photo-oxidation and photodegradation. 

Belloni J.,Treguer M., Remita H., De Keyzer R., Enhanced yield of photoinduced electrons in doped silver halide crystals. Nature, 1999,402, 865-867. De Keyzer R., Treguer M., Belloni J., Remita H., Photosensitive silver halide element with increased photosensitivity, US patent 6,436,625, Aug. 20,2002. 

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