Optical whiteners

The determination of optical whiteners in polymers by TLC and paper chromatography has been discussed by various workers [61,110-112]. These compounds include stilbene, cumarin, cyanine, imidazol, oxazol, thiozol, benzidine, pyrinidazol and carbostyryl derivitives. 

Wandel and co-workers [113] carried out separations on thin-layers of alumina and Kieselgel G using acetone - petroleum ether (30 70) and methylene chloride as the migration solvents and an UV light source for locating the separated compounds. 

Development on Silica Gel G with (A) 1,1,1-trichloroethane - dichloromethane (3 1) and (B) 1,1,1-trichloroethane - dichloromethane - methyl ethyl ketone (75 25 2) as solvent indicator sulfuric acid - anisaldehyde  

3 Isooctyl epoxy stearate Estynox 408 Baker Castor Oil 25, 39 30, 34, 55 Rose, brown, yellow 

4 2-Ethylhexyl epoxy tallate Flexol EP8 Union Carbide 25, 40 30, 34, 56 Rose, brown, yellow 

---

Spectrofluorimetric methods are applicable to the determination of aliphatic hydrocarbons, and humic and fulvic acids in soil, aliphatic hydrocarbons polyaromatic hydrocarbons, optical whiteners, and selenium in non-saline sediments, aliphatic aromatic and polyaromatic hydrocarbons and humic and fulvic acids in saline sediments. The only application found in luminescence spectroscopy is the determination of polychlorobiphenyl in soil. Generally speaking, concentrations down to the picogram (pg L 1), level can be determined by this technique with recovery efficiencies near f00%. 

Aliphatic hydrocarbons, triazine, substituted urea type and phenoxyacetic acid types of herbicides, Fluazifop and Fluazifop-butyl herbicides, ethylene diamine tetracetic acid salts in soil, aliphatic and polyaromatic hydrocarbons, phthalate esters, various organosulphur compounds, triazine herbicides, optical whiteners, mixtures of organic compounds and organotin compounds in non-saline sediments, aromatic hydrocarbons, humic and fulvic acids and mixtures of organic compounds in saline sediments and non-ionic surfactants and cobalamin in sludges. 

Triazine herbicides Phenoxyacetic acid herbicides Multiherbicide-insecticide mixtures Humic and fulvic acids Optical whiteners Mixtures of organic 1 1.2.1(n/s) 11.2.2(n/s) 1 l.2.6(n/s) 10.1.3.3(s) ... 

Stroll and Giger [1] have recently studied the bioaccumulation of three optical whitening agents in lake sediments obtained in Lake Griefensee, Switzerland. The compounds studied were ... 

Cyanuric chloride [2,4,6-trichloro-l,3,5-triazine (59)] is the basis of three major industrial applications triazine herbicides, triazine dyes, and optical whitening agents. It is not, however, made commercially by chlori-... 

Optical whiteners are used to make white clothes appear brighter. Can you suggest an explanation for the brightening action ... 

Blancophor [BASF], TM for optical whitening agents. FFG A comarin derivative used as whitening agent for wool, nylon, acetate rayon, and mixed fibers. HS Brands Stilbene derivatives used on cellulosic fibers, cotton and rayon fabrics, paper, and in household and industrial detergents. 

Chemical Constitution of Some Important Optical Whiteners [3,4]... 

The estimation of optical whiteners in substrate is really a difficult problem, but the qualitative and quantitative estimation of fluorescent brightener in solution by examination of absorption and/or emission spectra have been detailed [42-46], Since the brightener will differ in substantivity for a particular substrate with differences in their chemical structure, cost comparisons of performance can only be based upon evaluation of the treated substrates. Various techniques for such evaluation have been described [46-51]. 

In general, laundry aids contribute to the effectiveness of laundry detergents and provide unique functions. Laundry aids include builders, bleaches, enzymes, fabric softeners, and optical whiteners. 

Bleachit . [BASF] Reductive bleaching agent auxiliary for bleaching and optics whitening of wool and polyamide. 

Optical Whitener. (Pdymer Research Cotp. of Am.] Pdyester, nylon acetate whitener. 

Gascowhitener. [Gaston] Stilbene sulfonates cotton and polyester optical whiteners. 

Optical Whitener. CFt ymer Research Corp.ofAm.] Polyester, n on acetate whitener. 

Fibre types - changes in fibre type which cause a variation in wet-end chemistry also need to be monitored. Use of BCTMP in fine papers for increased bulk, for instance, can lead to increased demand for retention aid as well as for other effect chemicals, e.g. size, optical whitener. Variation in carry over of chemicals from de-inking plants can cause variable wet-end chemisfiy at the paper machine and where swings are significant this needs to be confiolled. Addition of fixative may be necessary to reduce negative impacts. 

Optical whiteners (OBA, FWA) are anionically charged and can have significant impact on the system charge and effectiveness of the retention and drainage aid. 

Air oxidation of p-nitrotoluenesulfonic acid to dinitrodibenzyldisulfonic acid, an important step in the manufacture of an intermediate in the production of optical whitening agents... 

---