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Phosphorescent materials were discovered in the 1700s, and people have been studying them and making improvements over the centuries.The development of strontium aluminate pigments in 1993 was spurred on by the need to find a substitute for glow-in-the-dark materials with high luminance and long phosphorescence, especially those that used promethium.
Strontium aluminate based pigments are now used in exit signs, pathway marking, and other safety related signage. [ 22 ] Zinc sulfide (left) and strontium aluminate (right), in visible light, in darkness, and after 4 minutes in the dark.
LSAT is the most common name for the inorganic compound lanthanum aluminate - strontium aluminium tantalate, which has the chemical formula (LaAlO 3) 0.3 (Sr 2 TaAlO 6) 0.7 or its less common alternative: (La 0.18 Sr 0.82)(Al 0.59 Ta 0.41)O 3. LSAT is a hard, optically transparent oxide of the elements lanthanum, aluminium, strontium and tantalum.
Strontium pigments. Strontium yellow (PY32): SrCrO 4; Titanium pigments. Titanium yellow (PY53): NiO·Sb 2 O 3 ·20TiO 2; Tin pigments. Mosaic gold: stannic sulfide (SnS 2). Zinc pigments. Zinc yellow (PY36): zinc chromate (ZnCrO 4), a highly toxic substance with anti-corrosive properties which was historically most often used to paint over metals.
The large size of strontium and barium plays a significant part in stabilising strontium complexes with polydentate macrocyclic ligands such as crown ethers: for example, while 18-crown-6 forms relatively weak complexes with calcium and the alkali metals, its strontium and barium complexes are much stronger.
The invention was patented in 1994 by Nemoto & Co., Ltd. and licensed to other manufacturers and watch brands that use different (brand) names. [2] These strontium aluminate–based phosphorescent pigments, often called lume, operate like a rechargeable light battery. After sufficient activation by sunlight, fluorescent, LED, UV (blacklight ...
Calx – calcium oxide; was also used to refer to other metal oxides. Chalcanthum – the residue produced by strongly roasting blue vitriol (copper sulfate); it is composed mostly of cupric oxide. Chalk – a rock composed of porous biogenic calcium carbonate. CaCO 3; Chrome green – chromic oxide and cobalt oxide.
Crystallography is used by materials scientists to characterize different materials. In single crystals, the effects of the crystalline arrangement of atoms is often easy to see macroscopically because the natural shapes of crystals reflect the atomic structure. In addition, physical properties are often controlled by crystalline defects.