Non-staining

Similar to phenols, they can cause staining and are often used in conjunction with carbon black filled elastomers (e.g., tyres) — although carbon black itself has antioxidant capacity. For non-staining applications, e.g., polypropylene carpets, a stoically hindered amine is used, e.g.,... 

Butylated hydroxytoluene, (2,6-Di-fert.-butyl-p-cresol), antidegradant - non-staining. 

DNPT is a free flowing light yellow powder. Alone DNPT decomposes at approximately 190 °C and produces 265 cm3 of gas per gram at STP. Nitrogen, nitrous oxide, various amines and water are produced. In a rubber environment the gas generation takes place within a range of 130-190 °C. A characteristic amine fishy odour is quite pronounced and can be offensive for some applications. DNPT is non-staining. 

In summary, the best oils for good stability in severe ageing environments, with good light stability and non-stain characteristics, are the paraffmics. The aromatics should only be used where the aforementioned requirements do not have to be met the naphthenics fall between the two in terms of properties. 

Aromatic oils are the most compatible with NR and give improved dispersion of fillers. If staining is a problem then a naphthenic oil with known low- or non-staining character should be used. 

Butylated p-Cresol-Dlcyclopentadlene Product. A complex non-staining oligomeric antioxidant marketed by Goodyear as "Wlngstay L" is the butylated reaction ptoduct of p-cresol and dlcyclopentadiene. After trying various analytical techniques, we found that GPC provides the best approach for following the reaction... 

Non-staining - An accelerator, antioxidant or similar substance that will not discolor other goods placed next to the rubber in which it is used. Sometimes used as well to describe non-discoloring in white or colored goods. 

For penetration stain, a 0.5 mm thick veneer of white, non-discolouring rubber, is applied under pressure to a sheet of the test rubber and the composite vulcanized. A test piece cut from the composite sheet is exposed to artificial light and examined for staining. The composition of the white veneer is left for agreement between the interested parties. Alternatively, part of a finished product incorporating a veneer may be used or the rubber test piece without the veneer coated with a non-staining white laquer. 

Chromium Intensification for Prints The technique is to bleach the print and then redevelop it in a non-staining developer, just as you would for a negative. Slow chlorobromide and chloride papers respond best to this technique. Cold-toned and bromide papers don t respond as well to chromium intensification, but changes will occur. If in doubt, give it a try. 

Farmer s reducer can cause a brownish stain with some papers. This problem can often be avoided by adding a small quantity of potassium iodide to the final print fixing bath. If the brownish residual stain still persists, a non-staining reducer should be used instead of Farmer s. 

The washing time can be shortened by at least half by placing the print for 10 to 20 seconds in a 3% solution of sodium carbonate. If this method is used, handle the prints carefully. This is because carbonate considerably softens the emulsion. Redevelop the image with any non-staining developer (e.g., Kodak D-72) for 2 to 5 minutes. The print should be washed for about Vi hour. Always use a fresh developer for print intensification. 

Figure 2. Upper surface necrosis on citrus leaf was produced by ozone in polluted ambient air. Fresh, non-stained section through an ozone-induced lesion on a citrus leaf. Dark region in palisade tissue collapsed several weeks after initial injury.

MERCERANT BEA is a non-phenolic, non-staining mercerizing assistant having excellent wetting ability in 18-25% caustic soda at room temperature. 

Solvent-based sealants one-component non-staining good weathering good chemical resistance perimeter pointing cladding pre-cast joints... 

Beneficial properties Excellent adhesion without the use of primers minimum surface preparation one-component system self-heahng excellent resistance to ultraviolet radiation good chemical resistance non-staining... 

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