Whitening agents FWAs

Initially, fluorescent whitening agents (FWAs) were used exclusively in textile finishing the detergent and paper industries followed thereafter. These products are also used in fiber spinning masses, plastics, and paints. 

Applications With the current use of soft ionisation techniques in LC-MS, i.e. ESI and APCI, the application of MS/MS is almost obligatory for confirmatory purposes. However, an alternative mass-spectrometric strategy may be based on the use of oaToF-MS, which enables accurate mass determination at 5 ppm. This allows calculation of the elemental composition of an unknown analyte. In combination with retention time data, UV spectra and the isotope pattern in the mass spectrum, this should permit straightforward identification of unknown analytes. Hogenboom et al. [132] used such an approach for identification and confirmation of analytes by means of on-line SPE-LC-ESI-oaToFMS. Off-line SPE-LC-APCI-MS has been used to determine fluorescence whitening agents (FWAs) in surface waters of a Catalan industrialised area [138]. Similarly, Alonso et al. [139] used off-line SPE-LC-DAD-ISP-MS for the analysis of industrial textile waters. SPE functions here mainly as a preconcentration device. 

Fluorescent whitening, of wool, 26 401—402 Fluorescent whitening agent (FWA), 26 400, 402... 

Uchiyama [11] applied this method to the determination of fluorescent whitening agents and alkyl benzenesulphonates and also methylene blue active substances in bottom sediment samples taken in a lake. The muds were filtered off with a suction filter and frozen until analyzed. About 20g of wet bottom mud was extracted three times with a methanol-benzene (1 1) mixture. After the solvent was evaporated using a water bath, the residue was dissolved in hot water and this solution used for analysis. Table 10.2 shows the analytical results for methylene blue active substances (MBAS), alkyl benzene-sulphonate (ABS), and fluorescent whitening agent (FWA) in bottom sediments. 

Optical brighteners (fluorescent whitening agents, FWAs) are used primarily in the textile, detergent, and paper industries and are also added to plastics [118], The mode of application and performance requirements differ greatly from one substrate to another, but there are five common basic principles ... 

Method A For white goods Hypochlorite Bleach Reduction or Peroxide Bleach + Fluorescent Whitening Agent (FWA). 

Fluorescent whitening agents (FWA) are a special type of chemical that can significantly increase the apparent whiteness of treated fabrics. They absorb UV radiation and re-emit the absorbed energy in the blue visible light range which makes the treated fabrics appear whiter. The easiest test for the effect of FWAs is simply a visual examination of the whiteness of treated fabrics. Manufacturer s recommendations should be followed in order to achieve the best whitening effect. 

The most widely used class of fluorescent whitening agents (FWAs) are known as CC/DAS types or cyanuric chloride diaminostilbene. The chromophore in these molecules is triazinylaminostilbene (Figure 8.30). The basic molecule can... 

Optical Brightening ents (OBA) - Fluorescent Whitening Agents (FWA) [2, 9,11]... 

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