Brightening agents

It is possible to divide these special colorants into such categories as daylight fluorescent colorants, phosphorescent colorants, and pearlescent colorants [14]. 

Pearlescent colorants are not particularly wavelength sensitive. The pearllike sheen produced is the result of external reflection and internal or lightscattering reflection. This condition is achieved by controlling the size and shape of the pearlescent crystals. 

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Dye Intermedia.tes, Dye intermediates are defined as those precursors to colorants that are manufactured within the dyes industry, and they are neady always colodess. Colored precursors are conveniendy termed color bases. As distinct from primaries they are only rarely manufactured in single-product units because of the comparatively low tonnages requited. Fluorescent brightening agents (FBAs) are neither intermediates nor tme colorants. Basic manufacturing processes for FBAs are described in Reference 18 (see Fluorescent whitening agents). 

Coumarin, 7-amino-7-(diethylamino)-, I, 333 Coumarin, 7-amino-4-methyl-fluorescence spectra, 3, 601 Coumarin, 7-amino-3-phenyl-brightening agents, I, 339 Coumarin, 4-aryl-occurrence, 3, 677 synthesis, 3, 810 Coumarin, 3-arylazo-4-hydroxy-structure, 3, 643 Coumarin, 3-bromo-reactions... 

Coumarin brightening agents, 1, 339-340 Coumarin-4-carboxylic acid methyl ester synthesis, 3, 806 synthesis, 3, 809... 

Fluorescent brightening agents, 1, 338-341 Fluoride ions nucleophilicity crown ethers and, 7, 756 Fluorides synthesis... 

Schbnungsmittel, n. fining agent, fining (for colors) brightening agent. 

Electrochemical oscillation during the Cu-Sn alloy electrodeposition reaction was first reported by Survila et al. [33]. They found the oscillation in the course of studies of the electrochemical formation of Cu-Sn alloy from an acidic solution containing a hydrosoluble polymer (Laprol 2402C) as a brightening agent, though the mechanism of the oscillatory instability was not studied. We also studied the oscillation system and revealed that a layered nanostructure is formed in synchronization with the oscillation in a self-organizational manner [25, 26]. 

OB, OB A Optical brightener, optical brightening agent PVI Pre-vulcanisation inhibitor... 

Descriptive terms such as fluorescent whitening agents , optical brighteners and optical bleaches have all been used for the products described in this chapter as FBAs. Many of these terms have validity and the term fluorescent brightening agents is preferred here only because it has been adopted in the indexes of Chemical Abstracts. 

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