Fastness to weather

Witterungsbedingung, /. atmospheric condition, witterungsbestandig, a. fast to weathering, (of steel) rust-resistant. 

It has been found that many of the reactive dyes have not the highest degree of fastness to natural weathering. When exposed over prolonged periods to the atmosphere they fade more rapidly than normal laboratory fastness tests would predict. Procion Yellow H-A, Procion Yellow M-6G, Procion Yellow M-R, and Procion Yellow H-SG are all deemed to be of borderline fastness to weathering. They are, nevertheless, in many cases superior to vat dyes because they do not induce accelerated oxidation of the cellulose on exposure to light. The deeper the shade the less apparent is the alteration due to weathering. 

Textiles- Tests for colour fastness—Part B03. colour fastness to weathering Outdoor exposure (ISO 105 B03. 1994). 

P(l) Pigments can be used as part of the basic resin or gei coat system to obtain a desired colour scheme. Users should consult with materials suppliers to ensure compatibility in processing and suitability for the intended application, including colour fastness to weathering, and whether their use will affect the long term structural stability. Some metallic salt based pigments may seriously lower the adhesion between fibre and matrix. 

Bismuth vanadate pigments have a much higher chroma than yellow iron oxide and nickel titanate pigments. In full shades and the palest tints, bismuth vanadate pigments show superlative fastness to weathering. 

Heat Stability (GPPS) 280C Fastness to weathering (PMMA) >90 Specific Gravity 1.27 cm3... 

Fastness to Weathering (PMMA) >85 Heat Stability (PC) 300C Melting Point >300 Specific Gravity 1.36 cm3... 

Fastness to Light (1/3 SD GPPS) 8 (8=best fastness to light) Fastness to weathering (PS) 5 Fastness to Migration (PS) +... 

Wetter, n. weather storm (Mining) damp, also air or ventilation, wetterbestdndig, a. weatherproof. Wetter-beatdndigkeit, /. weather resistance, -dynamit, n. (Mining) permissible dynamite, wetterdynamite. wetterecht, a. fast to exposure. 

Only a limited range of nitro, azo and anthraquinone disperse dyes exhibit adequate fastness to dry heat, light and weathering for application on polyester automotive fabrics. The structure of Cl Disperse Yellow 86 was modified to incorporate UV absorbers of the benzophenone, benzotriazole or oxalanilide types into the dye molecule. The derived dyes showed better fastness properties than the parent unsubstituted dye. Positioning of the photostabilising moiety within the dye molecule had little influence on the light fastness obtained, however. Built-in benzophenone residues were more effective than the other two types [177]. Nevertheless, several further monoazo and nitrodiphenylamine disperse dye... 

A number of diarylide yellow pigments are also available in the form of very opaque products with small specific surface areas. These are used to an appreciable extent in Chrome Yellow free paints, in packaging printing inks, and other media. Fastness to light and weather are much improved in opaque varieties, compared to the corresponding transparent types their rheological characteristics are superior. Opaque pigments are not resinated. 

A variety of diarylide yellow pigments are very fast to light and weather - although monoazo yellow and orange pigments are superior in this respect. 

P.V.29 types demonstrate excellent weatherfastness, much more so than other perylene pigments. Their impact on the market, however, is limited by their very dull shade of maroon. Full shades are deep brown, almost black. The pigment is very fast to organic solvents and overcoating. Commercial types are utilized especially in metallic finishes. Full shades frequently bronze upon exposure to weather. 

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