Pigment loading

Cost is an important factor ia exterior house paiats which are desigaed with low gloss because this permits higher pigment loading especially ia high... 

These are known as chemically pure (CP) cadmiums. With the development of other uses for cadmium and selenium, costs have risen substantially in recent years. Some cost reduction may be obtained by use of the cadmium Hthopones. These have the same relative shades but have been coprecipitated onto about 60% barium sulfate. The resulting extensions give better money value, if the higher pigment loading can be tolerated, with no loss in properties. 

Low Tinting Strength - The zinc borate has a refractive index similar to most organic polymers, which results in the retention of considerable translucency. This provides for easy visual inspection of the finished products and allows the use of lower pigment loadings in formulations requiring deep shades. 

This has an influence on the pigment load capacity and on the stability of high solid-containing latices (see Example 3-39). 

Loop agents can increase the rate of urine flow and enhance K+ excretion in acute renal failure. However, they do not shorten the duration of renal failure. If a large pigment load has precipitated acute renal failure (or threatens to), loop agents may help flush out intratubular casts and ameliorate intratubular obstruction. On the other hand, loop agents can theoretically worsen cast formation in myeloma and light chain nephropathy. 

Osmotic diuretics are used to increase water excretion in preference to sodium excretion. This effect can be useful when avid Na + retention limits the response to conventional agents. It can be used to maintain urine volume and to prevent anuria that might otherwise result from presentation of large pigment loads to the kidney (eg, from hemolysis or rhabdomyolysis). Some oliguric patients do not respond to osmotic diuretics. Therefore, a test dose of mannitol (12.5 g intravenously) should be given before starting... 

Ten typical pigments and/or extenders have been tested in an alkyd vehicle in both the presence and absence of chlorinated paraffin. These results were determined at pigment loadings of 40and 60°Jo PVC. 

Pigments ideally should be non-soluble solids with low oil absorption to facilitate dispersion and allow maximum pigment loading, which would also reduce the VOC content of the paint. In addition, pigments should be chemically inert, thermally stable, pure in their composition, and nontoxic. 

The many-flux model calculates pigment K and S in absolute units. In addition, the calculation of K and S goes beyond the white pigment to all colorants providing accurate opacity and pigment loading predictions. The data in Figure 4.3 show calculated K and S data, where both K and S are variable across the visible spectrum. 

Fundamentally, the most important aspect of particle size distribution is in its control to give both the proper distribution and the same distribution shipment to shipment. Variability in particle size distribution can lead to enormous difficulties in color matching and to unpredictable changes in pigment-loading requirements to obtain equivalent opacity. 

While the use of concentrate is prevalent in most resin categories, nearly all the TiCK used in finished products composed of polyethylene and polypropylene enters by way of solid concentrates. These concentrates typically vary in pigment loading level between 30 and 80% pigment by weight. The manufacture of these solid concentrates is usually done in internal mixers, continuous mixers, or multiple-screw... 

The PVC Emulsion types (containing up to 2.5% emulsifier) and those containing filler require a higher pigment loading because of their opacity. Since the emulsifiers are mostly alkaline, it is recommended to use silica-encapsulated metallic pigments to ensure consistent quality of the final product. 

The universal pigment concentrates offered by some pigment manufacturers contain 50% to more than 95% metallic pigment. They can be added directly for a final pigment loading of about 1% and will in most cases keep the processing cost down and result in a brilliant product. 

The recommended pigment loading (in relation to the polymer) for plastic compounds is as follows ... 

Flowlines are reduced by large-size metallic pigments and high pigment loading. 

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