Super-LumiNova is a brand name under which

strontium aluminate Strontium aluminate is an aluminate compound with the chemical formula (sometimes written as ). It is a pale yellow, monoclinic crystalline powder that is odourless and non-flammable. When activated with a suitable dopant (e.g. europium, written ...

–based non-

radioactive Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consid ...

and

nontoxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subs ...

photoluminescent Photoluminescence (abbreviated as PL) is light emission from any form of matter after the absorption of photons (electromagnetic radiation). It is one of many forms of luminescence (light emission) and is initiated by photoexcitation (i.e. photo ...

or afterglow

pigments A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compou ...

for illuminating markings on

watch dial A watch is a portable timepiece intended to be carried or worn by a person. It is designed to keep a consistent movement despite the motions caused by the person's activities. A wristwatch is designed to be worn around the wrist, attached by ...

s, hands and bezels, etc. in the dark are marketed. This technology offers up to ten times higher brightness than previous

zinc sulfide Zinc sulfide (or zinc sulphide) is an inorganic compound with the chemical formula of ZnS. This is the main form of zinc found in nature, where it mainly occurs as the mineral sphalerite. Although this mineral is usually black because of various i ...

–based materials. Super-LumiNova is based on LumiNova pigments, invented in 1993 by Nemoto & Co., Ltd. of Japan as a safe replacement for

radium Radium is a chemical element with the symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily reacts with nitrogen (rather t ...

-based

luminous paint Luminous paint or luminescent paint is paint that exhibits luminescence. In other words, it gives off Visible spectrum, visible light through fluorescence, phosphorescence, or radioluminescence. There are three types of luminous paints: fluoresc ...

s. Nemoto & Co. was founded in December 1941 as a luminous paint processing company and has supplied paint to the watch and clock industry for over 70 years. Besides being used in timepieces, Super-LumiNova is also marketed for application on: * Instruments: scales, dials, markings, indicators etc. * Scales: engravings, silkscreen-printing * Aviation instruments and markings * Jewelry * Safety- and emergency-panels, signs, markings * Aiming posts * Various other parts These types of

phosphorescent Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light (radiation) of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluor ...

pigments, often called lume, operate like a light battery. After sufficient activation by sunlight or artificial light, they glow in the dark for hours. Larger markings are visible for the whole night. This activation and subsequent light emission process can be repeated again and again, and the material does not suffer any practical aging. Strontium aluminate–based pigments have to be protected against contact with water or moisture, since this degrades the light emitting quality.

Alternative for afterglow pigments

Tritium Tritium ( or , ) or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with half-life about 12 years. The nucleus of tritium (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus o ...

-based devices called "gaseous tritium light source" (GTLS), that are an alternative for afterglow pigments, have the advantage of being self-powered and producing a consistent luminosity that does not fade during the night. However, they are radioactive and have a

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...

of slightly over 12 years. This means the intensity of the tritium-powered light source will gradually fade, generally becoming too dim to be useful after 20 to 30 years. Tritium was used on almost all Swiss Watches like

Rolex watches Rolex SA () is a British-founded Swiss watch designer and manufacturer based in Geneva, Switzerland. Founded in 1905 as ''Wilsdorf and Davis'' by Hans Wilsdorf and Alfred Davis in London, the company registered ''Rolex'' as the brand name of ...

from 1960 to 1998 when it was banned. and the original

Panerai Officine Panerai (also known simply as Panerai) is an Italian luxury watch manufacturer, and a wholly owned subsidiary of Compagnie Financière Richemont S.A. Officine Panerai designs, manufactures and markets watches through authorized dealer ...

Luminor dive watch Radiomir. Tritium-based substances ceased to be used by

Omega SA Omega SA is a Swiss luxury watchmaker based in Biel/Bienne, Switzerland. Founded by Louis Brandt in La Chaux-de-Fonds in 1848, the company formerly operated as ''La Generale Watch Co.'' until incorporating the name ''Omega'' in 1903, becoming ' ...

in 1997. By the late 1960s,

was phased out and replaced with much safer alternatives.

References

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External links

Technical Features Superluminova
- Archived fro
the original

Luminosity in watches

Luminescence Horology

Alternative for afterglow pigments

See also

References

External links