HOME

TheInfoList



OR:

Quinacridone is an
organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...
used as a
pigment A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...
. Numerous derivatives constitute the quinacridone pigment family, which finds extensive use in industrial
colorant A colourant/colour additive (British spelling) or colorant/color additive (American spelling) is a substance that is added or applied in order to change the colour of a material or surface. Colourants can be used for many purposes including printin ...
applications such as robust outdoor paints,
inkjet Inkjet printing is a type of printer (computing), computer printing that recreates a digital image by propelling droplets of ink onto paper or plastic substrates. Inkjet printers were the most commonly used type of printer in 2008, and range f ...
printer ink An ink cartridge or inkjet cartridge is a component of an inkjet printer that contains ink to be deposited onto paper during printing. It consists of one or more ink reservoirs and can include electronic contacts and a chip to exchange informa ...
,
tattoo ink Tattoo inks consist of pigments combined with a carrier, used in the process of tattooing to create a tattoo in the skin. These inks are also used for permanent makeup, a form of tattoo. Professional tattoo inks are available in many colors and ...
s, artists'
watercolor paint Watercolor (American English) or watercolour (Commonwealth English; see spelling differences), also ''aquarelle'' (; from Italian diminutive of Latin 'water'), is a painting method"Watercolor may be as old as art itself, going back to the S ...
s, and
color laser printer Laser printing is an electrostatic digital printing process. It produces high-quality text and graphics (and moderate-quality photographs) by repeatedly passing a laser beam back and forth over a Electric charge, negatively charged cylinder call ...
toner Toner may refer to: * Toner (printing), a powder mixture used in laser printers and photocopiers * Toner (skin care), a water-based lotion, tonic, or wash designed to cleanse the skin in preparation for other skincare products * Hair toner, produ ...
. As pigments, the quinacridones are insoluble. The development of this family of pigments supplanted the
alizarin Alizarin (also known as 1,2-dihydroxyanthraquinone, Mordant Red 11, C.I. 58000, and Turkey Red) is an organic compound with formula that has been used throughout history as a red dye, principally for dyeing textile fabrics. Historically it wa ...
dyes.


Synthesis

The name indicates that the compounds are a fusion of
acridone Acridone is an organic compound based on the acridine skeleton, with a carbonyl group at the ''9'' position. Synthesis and structure The molecule is planar. Optical spectra reveal that the keto tautomer predominates in the gas-phase and in ethanol ...
and
quinoline Quinoline is a heterocyclic aromatic organic compound with the chemical formula C9H7N. It is a colorless hygroscopic liquid with a strong odor. Aged samples, especially if exposed to light, become yellow and later brown. Quinoline is only sl ...
, although they are not made that way. Classically the parent is prepared from the 2,5-dianilide of
terephthalic acid Terephthalic acid is an organic compound with formula C6H4(CO2H)2. This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several million tons are produced annuall ...
(C6H2(NHPh)2(CO2H)2). Condensation of succinosuccinate esters with
aniline Aniline (From , meaning ' indigo shrub', and ''-ine'' indicating a derived substance) is an organic compound with the formula . Consisting of a phenyl group () attached to an amino group (), aniline is the simplest aromatic amine. It is an in ...
followed by
cyclization A cyclic compound (or ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring. Rings may vary in size from three to many atoms, and include examples where ...
affords dihydroquinacridone, which are readily dehydrogenated. The latter is oxidized to quinacridone. Derivatives of quinacridone can be readily obtained by employing substituted anilines. Linear ''cis''-Quinacridones can be prepared from
isophthalic acid Isophthalic acid is an organic compound with the formula C6H4(CO2H)2. This colorless solid is an isomer of phthalic acid and terephthalic acid. The main industrial uses of purified isophthalic acid (PIA) are for the production of polyethylene ...
.


Derivatives

Quinacridone-based
pigment A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...
s are used to make high performance paints. Quinacridones were first sold as pigments by Du Pont in 1958. Quinacridones are considered "high performance" pigments because they have exceptional color and weather fastness. Major uses for quinacridones include automobile and industrial coatings.
Nanocrystalline A nanocrystalline (NC) material is a polycrystalline material with a crystallite size of only a few nanometers. These materials fill the gap between amorphous materials without any long range order and conventional coarse-grained materials. Defi ...
dispersions of quinacridone pigments functionalized with
solubilizing Micellar solubilization (solubilization) is the process of incorporating the solubilizate (the component that undergoes solubilization) into or onto micelles. Solubilization may occur in a system consisting of a solvent, an association colloid (a ...
surfactant Surfactants are chemical compounds that decrease the surface tension or interfacial tension between two liquids, a liquid and a gas, or a liquid and a solid. The word ''surfactant'' is a Blend word, blend of "surface-active agent", coined in ...
s are the most common magenta printing ink. Typically deep red to violet in color, the hue of quinacridone is affected not only by the R-groups on the molecule but by the crystal form of the solid. For example, the γ crystal modification of unsubstituted quinacridone provides a strong red shade that has excellent color fastness and resistance to solvation. Another important modification is the β phase which provides a maroon shade that is also more weather resistant and light-fast. Both crystal modifications are more
thermodynamically stable In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. Colloquially, it may instead refer to kinetic persistence, the shelf-life of a metastable substance or system; th ...
than the α crystal phase. The γ crystal modification is characterized by a criss-cross lattice where each quinacridone molecule
hydrogen-bond In chemistry, a hydrogen bond (H-bond) is a specific type of molecular interaction that exhibits partial covalent character and cannot be described as a purely electrostatic force. It occurs when a hydrogen (H) atom, covalently bonded to a mo ...
s to four neighbors via single H-bonds. The β phase, meanwhile, consists of linear chains of molecules with double H-bonds between each quinacridone molecule and two neighbors. Basic modifications to the chemical structure of quinacridones include the addition of CH3 and Cl substituents. Some magenta shades of quinacridone are labeled under the proprietary name "Thio Violet" and "Acra Violet".


Semiconductor properties

Quinacridone derivatives exhibit intense
fluorescence Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with colore ...
in the dispersed state, and high
carrier mobility In solid-state physics, the electron mobility characterizes how quickly an electron can move through a metal or semiconductor when pushed or pulled by an electric field. There is an analogous quantity for holes, called hole mobility. The term ca ...
. These properties complement good photo-, thermal, and electrochemical stability. These properties are desired for
optoelectronic Optoelectronics (or optronics) is the study and application of electronic devices and systems that find, detect and control light, usually considered a sub-field of photonics. In this context, ''light'' often includes invisible forms of radia ...
applications including
organic light-emitting diode An organic light-emitting diode (OLED), also known as organic electroluminescent (organic EL) diode, is a type of light-emitting diode (LED) in which the emissive electroluminescent layer is an organic compound film that emits light in respon ...
s (OLEDs),
organic solar cell An organic solar cell (OSC) or plastic solar cell is a type of photovoltaic that uses organic electronics, a branch of electronics that deals with conductive organic polymers or small organic molecules, for light absorption and charge transport t ...
s (OSCs), and
organic field-effect transistor An organic field-effect transistor (OFET) is a field-effect transistor using an organic semiconductor in its channel. OFETs can be prepared either by vacuum evaporation of small molecules, by Polymer solution casting, solution-casting of polymer ...
s (OFETs). Due to interplay of intermolecular H-bonding and pi-pi stacking, quinacridone can form a self-assembling,
supramolecular Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces, ...
organic semiconductor Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals o ...
. :


References


Additional reading

* *{{cite journal , doi = 10.1002/adma.201204039 , title = Hydrogen-Bonded Semiconducting Pigments for Air-Stable Field-Effect Transistors , year = 2013 , last1 = Głowacki , first1 = Eric Daniel , last2 = Irimia-Vladu , first2 = Mihai , last3 = Kaltenbrunner , first3 = Martin , last4 = Gsiorowski , first4 = Jacek , last5 = White , first5 = Matthew S. , last6 = Monkowius , first6 = Uwe , last7 = Romanazzi , first7 = Giuseppe , last8 = Suranna , first8 = Gian Paolo , last9 = Mastrorilli , first9 = Piero , last10 = Sekitani , first10 = Tsuyoshi , last11 = Bauer , first11 = Siegfried , last12 = Someya , first12 = Takao , last13 = Torsi , first13 = Luisa , author-link13=Luisa Torsi, last14 = Sarıçiftçi , first14 = Niyazi Serdar , author-link14=Niyazi Serdar Sarıçiftçi , journal = Advanced Materials , volume = 25 , issue = 11 , pages = 1563–9 , pmid = 23239229, bibcode = 2013AdM....25.1563G , s2cid = 205247943 Organic semiconductors Organic pigments Diketones Heterocyclic compounds with 5 rings Nitrogen heterocycles Acridines