Coloration of plastics

Quinophthalones provide important dyes for the coloration of plastics (eg, Cl Solvent Yellow 33 (71), R = H [5662-03-3]) and for the coloration of polyester. For example. Cl Disperse Yellow 54 (71) R = OH, is the lea ding yellow dye for the transfer printing of polyester. 

The small range of azo condensation pigments has become established only because they combine outstanding fastness to light, heat, solvents and chemicals, finding acceptance for use in paints, printing inks and the coloration of plastics and some synthetic fibres. 

Strong migration tendencies practically exclude monoazo yellow and orange pigments from being used for the mass coloration of plastics they bleed and bloom considerably in most polymer systems. Again, Pigment Yellow 97 is an exception... 

The pigment is of regional importance in East Asia. P.Y.142 provides a bright yellow shade and is used for the coloration of plastics. 

P.Y.l 83 entered the market a few years ago and is considered a specialty product for the coloration of plastics. 

P.Y.171 was found in the Japanese market. Its prints are considerably redder than those made from P.Y.l 3 besides, its color is off the fastness limits for yellows on the European color scales for offset and letterpress application. P.Y.171 has a dull hue and is weaker than P.Y.13. The pigment is targeted for the coloration of plastics, such as PVC and PE. 

P.R.52 1 exhibits equally poor lightfastness in paints. Full shades, like those of P.R.57 1, match step 4-5 on the Blue Scale, a value which decreases considerably in white reduction. P.R.52 1 is of little interest for the coloration of plastics. 

Its main area of application is in graphics printing and in the mass coloration of plastics. 

Incorporated in its application medium, P.R.208 affords medium shades of red. The pigment exhibits good fastness to chemicals and solvents. Its main area of application is in the mass coloration of plastics and in packaging gravure printing inks. 

The fact that unstable P.B.15 types tolerate less than 200°C is a disadvantage in the coloration of plastics. With increasing temperature, the pigment frequently converts to the [l-modification, a tendency which is especially pronounced in polymer materials which contain aromatic rings, such as polystyrene, ABS, or PETP. 

P.R.270 exhibits a yellowish red shade and is recommended for the coloration of plastics and printing inks. 

Diazotization of 3,7-diaminodibenzothiophene 5,5-dioxide, which has the trivial name of benzidine sulfone, followed by coupling with phenols, anilines, or arylsulfonic acids gives bis-azo dyes varying in color from red-brown to blue. These dyes are useful for the coloring of plastics and cellulose. second class of compounds based on 3,7-diamino-... 

Because of their brilliant pure red and yellow shades cadmium pigments, e.g. Cl Pigment Red 108, CdS-xCdSe, have found widespread use in the coloration of plastics, but toxicological problems have led to restrictions on their use and to the introduction of safer replacement products. 

Ahmed, M. (1979) In Coloring of plastics theory and practice. Van Nostrand Rhein-hold. New York, chap 6... 

Properties and Uses. As far as resistance to light, weather, and chemicals is concerned, transparent iron oxides behave in a similar manner to the opaque iron oxides (see Section 3.1.1). In addition, they show a high UV absorption, which is exploited in applications such as the coloring of plastic bottles and films used in the packaging of UV-sensitive foods [5.276], [5.277]. 

Worldwide consumption of transparent iron oxides is 2000 t/a. They are mainly used in the production of metallic paint in combination with flaky aluminum pigments and in the coloring of plastics for bottles and fibers. 

Quinophlhalones. Like the hydroxy azo dyes, quinophthalonc dyes can. in theory, exhibit tautoiuerism. The dyes are synthesized by the condensation of quinaldine derivatives with phthalic anhydride. Quinophlhalones provide important yellow dyes for the coloration of plastics and lor the coloration of polyester. 

The creation of this publication started with the Color and Appearance Division (CAD) of the Society of Plastics Engineers. In 1979, a small volume was published titled Coloring of Plastics. This volume, with numerous authors, was edited by Thomas G. Webber under the sponsorship of the Color and Appearance Division. This was the first publication dedicated totally to the coloring of plastic materials. Thomas Webber s book was the first and only volume truly focusing on the subject. This book was the primer for the coloring of plastics industry. However, many years later the book was hopelessly outdated. The need for such a volume now is as great,... 

Coloring of Plastics, Fundamentals, 2nd edition. Edited by Robert A. Charvat ISBN 0-471-13906-8 Copyright 2004 by John Wiley and Sons, Inc. 

All the above is prolog to this publication. This new publication is divided into two major parts. Volume I deals with the many technology issues that impact the coloring of plastics today. Volume II will cover the major polymer families and deliver basic information on the coloring of those polymers. 

In this brief chapter we hope we have been able to establish in the reader s mind that the coloring of plastics materials is not a simple process. However, we would like the reader to know that it is also not an impossible problem. If one takes a sound scientific approach to variables analysis as it relates to color, for the most part the difficulties can be eliminated. As you have seen, there are many variables that must be contended with and these variables do not always act independent of each other. This means we need to define, understand, and control as many variables as possible. We suggest you start with the simplistic first theorem, which states The most likely reason that your new computer is not working is you don t have it plugged in (actual data from computer support companies). Start with the simple and work to the complex it save lots of time and is good, sound scientific thinking. Below are some simple questions to help you remember the basic variables that most often cause color problems. It is by no means all inclusive, for there are times when the solutions are complicated, but this is usually the exception and not the rule. 

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