Inorganic pigments colored titanium oxides

Inorganics are denser and usually of a larger particle size. Common inorganic pigments include iron oxides in buff colors, titanium dioxide in white, lead and zinc... 

Pigments are inert and, unlike dyes, insoluble in the medium in which they are incorporated. Both inorganic and organic pigments are used in plastics. Most colorants are inorganic pigments, with titanium dioxide being the most commonly used and iron oxides the second most common. 

Some inorganic compounds are used as food additives and food colorants. They include titanium dioxide, carbon black, iron oxides, ultramarin, and calcium carbonate. Some of them are important for properties other than the ability to impart color. Titanium is the most commonly used inorganic pigment in food and will be briefly discussed below. ° "°... 

Some polymeric objects, such as rubber tires, are black because of the presence of high proportions of carbon black filler. Many other products, including some paints, are white because of the presence of titanium dioxide (titanium (IV) oxide), the most widely used inorganic pigment. Over 50,000 t of colorants are used annually by the polymer industry. 

Inorganic pigments, such as titanium dioxide, zinc oxide or carbon black act as efficient light screens and thus protect plastics against photodegradation (Accorsi and Yu, 1998 Rabek, 1990 Allen, 1989). Colored iron oxides and organic pigments, such... 

An increasing number of colored inorganic pigments are FDA-compliant. Historically, yellow iron oxide, red iron oxide, black iron oxide, zinc ferrite, burnt umber, raw and burnt sienna, channel carbon black, chromium oxide green, ultramarine blue, cobalt blue and copper chrome black have enjoyed FDA—compliant status, under 21 CFR 178.3297, Colorants for Polymers . More recently, the FDA has been successfully petitioned with regard to nickel titanium yellow, chrome titanium yellow, and cobalt green under 21 CFR 170.39, Threshold of Regulation for Substances Used in Food-Contact Articles . 

Most colors exempt from certification are obtained from animal, vegetable, or mineral sources. Most of the inorganic pigments are synthetically produced. Some examples would be titanium dioxide, synthetic iron oxide, and zinc oxide. 

Colorants Coloration of plastics, dyes, organic and inorganic pigments Benzidene (diarylide) (yellow), nickel azo (yellow), benzimidazole, copper phthalocyanine (blue-green) and isoindolinone (yellow-orange and reds), heavy metal oxides and sulfides, heavy metals and titanium dioxide, dihydroindolizine (DHI) and thermochromic antimony... 

Titanium dioxide strongly absorbs light in the near-UV portion of the spectrum (200 nm - 380 nm) so it does provide some degree of protection for a polyolefin matrix. Barium sulphate, zinc sulfide, and antimony oxide are examples of other inorganic white colorants that can be utilized in durables. These pigments are often utilized since they effectively reflect light in the ultraviolet region. 

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