Colour shade

As a general rule, wherever an indicator does not give a sharp end point, it is advisable to prepare an equal volume of a comparison solution containing the same quantity of indicator and of the final products and other components of the titration as in the solution under test, and to titrate to the colour shade thus obtained. 

Masterbatch A plastics compound which includes a high concentration of an additive or additives. Masterbatches are designed for use in appropriate quantities with the basic resin or mix so that the correct end concentration is achieved. For example, colour masterbatches for a variety of plastics are extensively used as they provide a clean and convenient method of obtaining accurate colour shades. 

Opaque glazes contain opacifiers either in frit (zircon, fluorides) or as a secondary component (Sn02). They are used wherever the body colour is to be covered or to attain pastel colour shades, in particular in building ceramics. Lead-free glazes are likewise given preference in industrial production. 

In combination with clear water-soluble dyes, fancy colour shades can be achieved. In conjunction with other fruit flavours, unlimited combinations are possible. 

Some colours, like all the different anthocyanins, change colour shade with varying pH. At pH around 3, where they are most commonly used, they will display bright pink and reddish hues. Moving towards neutral pH the colour will change through purplish-red to mauve and bluish shades and, depending on the anthocyanin source, can even appear dull and dark. 

Many food and beverage manufacturers are still reluctant to nse natural colours due to former issues such as dull colour shades, poor stability with rapid fading and difficulties in handling. However, over the past ten years natural colour manufacturers have discovered new techniqnes within formulation and processing that are able to resolve these issues. Combined with the use of high-quality raw materials it is now possible to develop and manufacture products that have better functional properties both daring handhng and in the final food products. 

Natural dyes such as indigo, woad, or madder lost their position due to d3mamic development of textile industry in the XVIIIth century. In the second half of the XIXth century, there started a S)mthesis of intermediate products and new dyes not having equivalents in nature of various colours, shades, and high quality (resistance to chemical factors, light, friction). 

Influence of aggregation structure and particle size on the colour shade of nano-dispersed -carotene hydro-sols. - Thereby, and by using blends of carotenoids, such as carotene, lycopene, S -apo-ji-carotenal and canthaxanthin, the colour of soft drinks can be adjusted from light yellow to red violet. 

The components are recut from the fabric that remains from the spreading process. A piece of fabric with the correct colour shade must be found and the component is recut using its original pattern piece. All notches and drill marks are also performed and if necessary, the interlining is cut and the component is fused. The new component is marked and replaced in the bundle at the same place (the original sequence of the components in the bundle must not be altered). 

In respect of colour shade, cochineal can substitute the synthetic colours and it possesses a far better light stability (Ohlen and Bertelsen, 1989). According to Danish food legislation, cochineal is permitted at levels up to 100 ppm when calculated as the active component carmine acid (Positivlisten, 1988). 

In contrast, the proper cured colour is related to the formation of nitrosylmyoglobin. If the curing agents are completely left out of the recipe, this component is not formed and the sausages appear greyish to reddish, the colour shade being dependent on the degree of comminution and calibre size (Wirth, 1991). 

The compounds fiuoresee dark blue (pyridoxal-5 -phosphate, yellow [152]) on dry silica gel layers containing fluorescent additive, when illuminated with UV light 3 xg can be detected in 254 nm, 10 (xg in 365 nm. These colours depend somewhat on the layer and can be modified by treatment with ammonia and alkahes [152]. All Bg compounds yield a bluish product after spraying with 2,6-dichloro- or 2,6-dibromoquinone-chloroimide (Rgt. Nos. 66 and 62 respectively) and subsequent treatment with ammonia vapour (limit of detection 0.1 [xg pyridoxal is the weakest, 0.5—1 [xg). Yamada and Saito [152] have found that the colour shades vary somewhat and depend on the carrier. 

In addition to the colour shade and decoration, design requests are satisfied by the various geometric types of cooktop panels for built-in or freestanding cookers rectangular, oval-shaped, circular, square, with and without holes for control devices. These are advantages in design that no other cooking system can offer, and it is the properties of this product which make them possible. 

As mentioned previously, the difficulties in obtaining colourable blends from bitumen mixtures have forced the research and production of synthetic substances which are easily colourable, with mechanical properties similar to those of bitumen, allowing their use in most applications where coloured mixtures are advised. These products, known as binders or light synthetic binders, because of their light tones, are a mixture of substances that form a macroscopically compatible system. The colouring is easy and with 1-2% w/w pigment, colour shades are obtained which meet most of the desired colour range [5]. 

Pigments are probably the most widely used additive and generally the most demanding. The customer may well be critical of the smallest discrepancy in colour shade, opacity or transparency, gloss etc. particularly where matching with other components is necessary such as painted automotive parts and thermoformed bathroom items and so on. 

For this purpose, the colour rendering of the image section displaying pencils in 12 different colour shades was evaluated once by the CMS and once using the mirror (see Fig. 29). 

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