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Thermochromic
Thermochromism is the property of substances to change color due to a change in temperature. A mood ring is an excellent example of this phenomenon, but thermochromism also has more practical uses, such as baby bottles which change to a different color when cool enough to drink, or kettles which change color when water is at or near boiling point. Thermochromism is one of several types of chromism. Organic materials Thermochromatic liquid crystals The two common approaches are based on liquid crystals and leuco dyes. Liquid crystals are used in precision applications, as their responses can be engineered to accurate temperatures, but their color range is limited by their principle of operation. Leuco dyes allow wider range of colors to be used, but their response temperatures are more difficult to set with accuracy. Some liquid crystals are capable of displaying different colors at different temperatures. This change is dependent on selective reflection of certain wavelengt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermochromatic Ink
Thermochromic ink (also called thermochromatic ink) is a type of dye that changes color when temperatures increase or decrease. Often used in the manufacture of many toys or product packaging, as well as thermometers. Thermochromic ink can also turn transparency and translucency, transparent when heat is applied; an example of this type of thermochromic ink is found on corners of an Test (assessment), examination mark sheet. This proves that the sheet has not been edited or photocopied, and also on certain pizza boxes to show the temperature of the product. Use on packaging can be to detect temperature history during shipping and to indicate proper heating in an oven. Examples On June 20, 2017, the United States Postal Service released the first application of thermochromic ink to postage stamps in its 2017 Total Solar Eclipse stamp, Total Eclipse of the Sun Forever stamp to commemorate the solar eclipse of Solar eclipse of August 21, 2017, August 21, 2017. When pressed with a fin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generra Hypercolor
Hypercolor was a line of clothing, mainly T-shirts and shorts, that changed color with heat. They were manufactured by Generra Sportswear Company of Seattle and marketed in the United States as Generra Hypercolor or Generra Hypergrafix and elsewhere as Global Hypercolor. They contained a thermochromic pigment made by Matsui Shikiso Chemical of Japan, that changed between two colors—one when cold, one when warm. The shirts were produced with several color change choices beginning in 1991. The effect could easily be permanently damaged, particularly when the clothing was washed in hotter than recommended water, ironed, bleached, or tumble-dried. Generra Sportswear Co. had originally been founded as a men's sportswear distributor and importer in Seattle in 1980. The company was sold to Texas-based Farah Manufacturing Co. in 1984 and bought back by its founders in 1989. In 1986, the company added childrenswear and womenswear items to their portfolio. They struggled to meet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiropyran
A spiropyran is a type of organic chemical compound, known for photochromic properties that provide this molecule with the ability of being used in medical and technological areas. Spiropyrans were discovered in the early twentieth century. However, it was in the middle twenties when Fisher and Hirshbergin observed their photochromic characteristics and reversible reaction. In 1952, Fisher and co-workers announced for the first time photochromism in spiropyrans. Since then, there have been many studies on photochromic compounds that have continued up to the present. Synthesis There are two methods for the production of spiropyrans. The first one can be by condensation of methylene bases with o-hydroxy aromatic aldehydes (or the condensation of the precursor of methylene bases). Spiropyrans generally could be obtained by boiling the aldehyde and the respective benzazolium salts in presence of pyridine or piperidine. The general formula of the synthesis of spiropyrans is shown in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcapsule
Microencapsulation is a process in which tiny particles or droplets are surrounded by a coating to give small capsules, with useful properties. In general, it is used to incorporate food ingredients, enzymes, cells or other materials on a micro metric scale. Microencapsulation can also be used to enclose solids, liquids, or gases inside a micrometric wall made of hard or soft soluble film, in order to reduce dosing frequency and prevent the degradation of pharmaceuticals. In its simplest form, a microcapsule is a small sphere comprising a near-uniform wall enclosing some material. The enclosed material in the microcapsule is referred to as the core, internal phase, or fill, whereas the wall is sometimes called a shell, coating, or membrane. Some materials like lipids and polymers, such as alginate, may be used as a mixture to trap the material of interest inside. Most microcapsules have pores with diameters between a few nanometers and a few micrometers. Materials generally used f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromism
In chemistry, chromism is a process that induces a change, often reversible, in the colors of compounds. In most cases, chromism is based on a change in the electron states of molecules, especially the π- or d-electron state, so this phenomenon is induced by various external stimuli which can alter the electron density of substances. It is known that there are many natural compounds that have chromism, and many artificial compounds with specific chromism have been synthesized to date. It is usually synonymous with chromotropism, the (reversible) change in color of a substance due to the physical and chemical properties of its ambient surrounding medium, such as temperature and pressure, light, solvent, and presence of ions and electrons. Chromism is classified by what kind of stimuli are used. Examples of the major kinds of chromism are as follows. * thermochromism is chromism that is induced by heat, that is, a change of temperature. This is the most common chromism of all. * pho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermochromic Mug
A mug is a type of cup typically used for drinking hot drinks, such as coffee, hot chocolate, or tea. Mugs usually have handles and hold a larger amount of fluid than other types of cup. Typically, a mug holds approximately of liquid. A mug is a less formal style of drink container and is not usually used in formal place settings, where a teacup or coffee cup is preferred. Shaving mugs are used to assist in wet shaving. Ancient mugs were usually carved in wood or bone, ceramic or shaped of clay, while most modern ones are made of ceramic materials such as bone china, earthenware, porcelain, or stoneware. Some are made from strengthened glass, such as Pyrex. Other materials, including enameled metal, plastic, or steel are preferred, when reduced weight or resistance to breakage is at a premium, such as for camping. A travel mug is insulated and has a cover with a small sipping opening to prevent spills. Techniques such as silk screen printing or decals are used to apply decorati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypercolor
Hypercolor was a line of clothing, mainly T-shirts and shorts, that changed color with heat. They were manufactured by Generra Sportswear Company of Seattle and marketed in the United States as Generra Hypercolor or Generra Hypergrafix and elsewhere as Global Hypercolor. They contained a thermochromic pigment made by Matsui Shikiso Chemical of Japan, that changed between two colors—one when cold, one when warm. The shirts were produced with several color change choices beginning in 1991. The effect could easily be permanently damaged, particularly when the clothing was washed in hotter than recommended water, ironed, bleached, or tumble-dried. Generra Sportswear Co. had originally been founded as a men's sportswear distributor and importer in Seattle in 1980. The company was sold to Texas-based Farah Manufacturing Co. in 1984 and bought back by its founders in 1989. In 1986, the company added childrenswear and womenswear items to their portfolio. They struggled to meet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weak Acid
Acid strength is the tendency of an acid, symbolised by the chemical formula HA, to dissociate into a hydron (chemistry), proton, H+, and an anion, A-. The Dissociation (chemistry), dissociation of a strong acid in solution is effectively complete, except in its most concentrated solutions. :HA -> H+ + A- Examples of strong acids are hydrochloric acid (HCl), perchloric acid (HClO4), nitric acid (HNO3) and sulfuric acid (H2SO4). A weak acid is only partially dissociated, with both the undissociated acid and its dissociation products being present, in solution, in Equilibrium chemistry, equilibrium with each other. :HA H+ + A- Acetic acid (CH3COOH) is an example of a weak acid. The strength of a weak acid is quantified by its acid dissociation constant, K_\ce value. The strength of a weak organic chemistry, organic acid may depend on substituent effects. The strength of an inorganic chemistry, inorganic acid is dependent on the oxidation state for the atom to which the prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Violet Lactone
Crystal violet lactone (CVL) is a leuco dye, a lactone derivate of crystal violet 10B. In pure state it is a slightly yellowish crystalline powder, soluble in nonpolar or slightly polar organic solvents. The central carbon in the leuco form is in a tetrahedral configuration, with four covalent bonds. In an acidic environment, the lactone ring is broken, with the oxygen detaching from the central carbon. This now-trivalent position is a planar carbocation that is resonance stabilized, interconnecting the π systems of the aromatic rings and the amino functional groups. This single large conjugated system is a chromophore with strong absorption in visible spectrum, giving this compound its distinctive color. This chemical is usually drawn in the resonance structure with the cation on nitrogen. : It was the first dye used in carbonless copy papers, and it is still widely used in this application. It is also the leuco dye component in some thermochromic dyes, e.g. in the Hypercolor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dodecanol
Dodecanol , or lauryl alcohol, is an organic compound produced industrially from palm kernel oil or coconut oil. It is a fatty alcohol. Sulfate esters of lauryl alcohol, especially sodium lauryl sulfate, are very widely used as surfactants. Sodium lauryl sulfate, ammonium lauryl sulfate, and sodium laureth sulfate are all used in shampoos. Lauryl alcohol is tasteless and colorless with a floral odor. Production and use In 1993, the European demand of dodecanol was around 60 thousand tons per year (Tt/a). It can be obtained from palm kernel or coconut oil fatty acids and methyl esters by hydrogenation. It may also be produced synthetically via the Ziegler process. A classic laboratory method involves Bouveault-Blanc reduction of ethyl laurate. Dodecanol is used to make surfactants, lubricating oils, pharmaceuticals, in the formation of monolithic polymers and as a flavor enhancing food additive. In cosmetics, dodecanol is used as an emollient. It is also the precursor to do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
