Fluorescent brightener effect

Fluorescent whitening agents (LD) Create a brightening effect Substantivity on fabrics Compatibility with other ingredients like bleaches Bistriazinyl derivatives of 4,4 -diamino-stilbene-2,2 -disulfonic acid 0.1-0.5%... 

Pyrazolo[3,4- [1,2,3]triazoles 85, when applied as fluorescent brighteners on polyester fibers have been found to give moderate whitening effects with a violet fluorescence, and they were categorized as grade one fluorescent brighteners <1992MI95>. 

Cationic dyes are occasionally used fur blueing or brightening the hair, frequently in combination with a fluorescent dyes. P. Krais discovered the brightening effect in 1929 by impregnation of rayon with a horsechestnut extract known as esculin, a fluorescent glycoside of 6,7-dihydroxycoumarin. Coumarin derivates are still used for wool and fur hair. 

Anionic softeners are heat stable at normal textile processing temperatures and compatible with other components of dye and bleach baths. They can easily be washed off and provide strong antistatic effects and good rewetting properties because their anionic groups are oriented outward and are surrounded by a thick hydration layer. Sulfonates are, in contrast to sulfates, resistent to hydrolysis (Fig. 3.3). They are often used for special applications, such as medical textiles, or in combination with anionic fluorescent brightening agents. 

Decomposition Ozonisation Very effective, side effect disinfection but need of special equipment, probability of damaging dyestuffs, fluorescent brighteners and sensitive fibres like nylon... 

Renilla (sea pansy) luciferin (and certain of its synthetic analogues) produces a brilliant blue chemiluminescence when dissolved in organic solvents such as dimethylformamide and involves the anion of 2-acetamido-3-benzyl-5-(p-hydroxy-phenyl)pyrazine (21) (1191). 5-Hydrazino-2-hydrazinocarbonylpyrazine is effective against mycobacterium tuberculosis and m. kansasii in vitro (1098). Aminonitro-pyrazines have been claimed as useful yellow dyes for wool (1180) and tetraamino-pyrazine (1180) and A -substituted amides of 2-carboxy-3,5-bismethylamino-6-(A -methylcarbamoyl)pyrazines (1192) as fluorescent brighteners (or optical bleaching agents) for textiles. 

Provided only medium shades are selected for the basic dye component there should be no significant staining of the deep dye yarn. For colour and white effects, selected acid dyes are used, and if desired, a fluorescent brightening agent may be added to improve the white of the type 120. Acid dyes reserving basic dyeable yarn in shades up to standard depth are ... 

There are several drawbacks to use of softeners. Repeated use of softeners may cause reduced water absorbency of garments (particularly with distearyl dimethyl ammonium chloride). Softeners may also reduce the effectiveness of anionic fluorescent brighteners [2]. They may impart a greasy feel, and may stain fabrics when overdosed or too thick. Softeners can also reduce the effectiveness of flame retardancy agents on fabrics. 

One study on dye fading in films of 2GT containing fluorescent brightening agents has investigated the effect of the glass transition temperature on this process. ... 

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