Light stabilizers classification

According to the four possibilities of UV protection mechanism described above, the light stabilizer classes can be designated as (1) UV absorbers, (2) quenchers of excited states, (3) hydroperoxide decomposers, and (4) free radical scavengers. It must be mentioned, however, that this classification is a simplification and that some compounds may be active in more than one way and often do so. 

Details DIBP is one of the rare odourless plasticisers with excellent heat/light stabilities, and it is inexpensive. DIBP is a commonly used as a plasticiser for cellulose nitrate production. DIBP has not yet undergone an EU classification and labelling assessment and it is very unlikely that it has any toxicological effects. Since it is not known for sure, its toxicology information is not given here (http //w w w. dibp-facts.com/index.asp page=3). 

Classification Nonaromatic phosphorus compd. Empirical C9H21O3P Formula [(CH3)2CH]3P03 Properties Colorless liq. char, odor misc. with most common org. soivs. insol. in water m.w. 208.27 dens. 0.914 (20/4 C) b.p. 94-96 C (50 mm) flash pt. (COC) 73.9 C ref. index 1.4110 Toxicology LD50 (oral, rat) 167 mg/kg, (IP, mouse) 500 mg/kg, (skin, rabbit) > 2 g/kg poison by ing. mod. toxic by IP route irritant mutagenic data TSCA listed Precaution Combustible hydrolyzes slowly in water minimize exposure to air Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of POx Storage Moisture-sensitive Uses Intermediate for insecticides, pharmaceuticals, mfg. of phosphonate esters, acids, and salts component of vinyl stabilizers lubricant additive specialty solvent heat and light stabilizer, antioxidant, metal chelator for polyester... 

Dyes are classified and discussed by structure. To aid in this identification the AATCC and The Society of Dyers and Colorists have published the Color Index. This publication details dye classifications by structure, generic name and an identifying Constitution Number. Other information listed is solubility parameters, heat and light stability and chemical resistance. Recently, the larger dye manufacturers have chosen not to disclose a great deal of information concerning new dyes. 

In light of the variety of behaviour exhibited by solvates, Byrn (1982) has suggested a classification scheme for crystal solvates based on that behaviour, rather than on stability. He proposed that the solvates for which the solvent can be removed from the crystal and added back to the crystal reversibly without greatly changing the X-ray powder diffraction pattern (Section 4.4) would be considered pseudopoly-morphic solvates. Those which undergo a change in structure, as evidenced by a different powder diffraction pattern, would be described as polymorphic solvates. The appellation does not seem to have been adopted by many other workers. 

This relates to the general structural requirements of workplaces, such as the stability of buildings, soundness of floors and the load-bearing capacity of beams. Environmental working conditions, such as the levels of lighting, ventilation and humidity, feature in this classification. 

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