Optical Brighteners

Brighteners, Optical


(also optical bleaches), colorless or slightly colored organic compounds that absorb ultraviolet rays of wavelengths between 300 and 400 millimicrons (mμ). They subsequently convert the ultraviolet rays into blue or violet light in the 400–500 mμ range, which compensates for an insufficiency of blue rays in the light that is reflected from the brightened material. Optical brighteners are used with many materials, including cotton, synthetic fibers, paper, wool, raw silk, leather, fur, and plastics. This process imparts a high degree of brightness to colorless materials and brightness and contrast to colored articles.

Most of the optical brighteners that are used with cellulose materials are stilbene-triazine derivatives of the general structural formula

where Rʹ and Rʺ are such groupings as NHR, NR2, NHC2H4-OH, N(C2H4OH)2, NHAr, OCH3, NHC6H4SO3Na, NH2, and OH (R being any alkyl radical and Ar being any aryl radical).

Optical brighteners are used during various stages in the preparation and processing of natural and synthetic materials. Optical brightening and dyeing are similar processes, especially the brightening and direct dyeing of cellulose materials. However, considerably less optical brightener than dye is needed to produce the desired effect. Optical brighteners that are insoluble in water may be used either in highly dispersed form or in solution with organic solvents.

References in periodicals archive ?
composition: 5-15% anionic surfactants, phosphates, not more than 5% non-ionic surfactants, oxygen-containing bleaches, polycarboxylates, optical brighteners, enzymes, perfume.
Standard Cyclops sensors are available for detecting: in vivo Chlorophyll, Crude Oil, Refined Fuels, CDOM/FDOM (dissolved organic material), Blue/Green Algae, Fluorescein Dye, Rhodamine Dye, PTSA Dye, Optical Brighteners, Tryptophan, and Turbidity.
Dreft purtouch has a formula that is free of dyes, chlorine, phosphates, ethanolamine and optical brighteners, and is made with 100-percent renewable wind power electricity at a zero manufacturing waste to landfill site.
The solution is compatible with softeners, optical brighteners and most auxiliary agents and does not react with other chemical treatments.
USPRwire, Wed Apr 13 2016] Optical Brighteners Market by Application (Paper, Fabrics, Detergents & Soaps, Synthetics & Plastics & Others), by End User (Consumer Products, Textiles & Apparel, Packaging, Security & Safety & Others) - Global Forecast to 2020
A tampon is one of the few things you can buy that is not pretreated with optical brighteners," says coauthor David Lerner.
Optical brighteners also are used in paper, cosmetics, and clothing fiber industries.
Variables such as lighting conditions and optical brighteners can skew the perceived color results, however, these are beyond the scope of this article.
of a co-surfactant constituent selected from the group consisting of nonionic, cationic, amphoteric, zwitterionic surfactants, and mixtures thereof; one or more constituents selected from the group consisting of coloring agents, fragrances and fragrance solubilizers, viscosity modifying agents thickeners, pH adjusting agents and pH buffers, optical brighteners, opacifying agents, hydrotropes, abrasives, and preservatives; and water.
LennoKraft contains no optical brighteners and is suitable for the production of food packaging.
Also supplies Markscreen hindered amine light stabilizers (HALS), bensophenone and benzotriazole uv absorbers, and optical brighteners for polyolefins, PVC and other thermoplastics.
Optical brighteners work by absorbing light from the UV end of the spectrum and emitting light in the visible blue/white range of the spectrum.