Lipophobicity, also sometimes called lipophobia (from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

λιποφοβία from λίπος ''lipos'' "fat" and φόβος ''phobos'' "fear"), is a chemical property of

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

s which means "

fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers specif ...

rejection", literally "fear of fat". Lipophobic compounds are those not soluble in

lipid Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing ...

s or other non-polar

solvent A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas ...

s. From the other point of view, they do not absorb fats. "Oleophobic" (from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

''oleum'' "oil",

ελαιοφοβικό ''eleophobico'' from έλαιο ''eleo'' "oil" and φόβος ''phobos'' "fear") refers to the physical property of a

molecule A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...

that is seemingly repelled from oil. (Strictly speaking, there is no repulsive force involved; it is an absence of attraction.) The most common lipophobic substance is

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

Fluorocarbons Fluorocarbons are chemical compounds with carbon-fluorine bonds. Compounds that contain many C-F bonds often have distinctive properties, e.g., enhanced stability, volatility, and hydrophobicity. Several fluorocarbons and their derivatives are ...

are also lipophobic/oleophobic in addition to being

hydrophobic In chemistry, hydrophobicity is the chemical property of a molecule (called a hydrophobe) that is seemingly repelled from a mass of water. In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, thu ...

Uses

A lipophobic coating has been used on the

touchscreen A touchscreen (or touch screen) is a type of electronic visual display, display that can detect touch input from a user. It consists of both an input device (a touch panel) and an output device (a visual display). The touch panel is typically l ...

s of

Apple An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are agriculture, cultivated worldwide. The tree originated ...

iPhone The iPhone is a line of smartphones developed and marketed by Apple that run iOS, the company's own mobile operating system. The first-generation iPhone was announced by then–Apple CEO and co-founder Steve Jobs on January 9, 2007, at ...

s since the 3GS, their

iPad The iPad is a brand of tablet computers developed and marketed by Apple Inc., Apple that run the company's mobile operating systems iOS and later iPadOS. The IPad (1st generation), first-generation iPad was introduced on January 27, 2010. ...

Nokia Nokia Corporation is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporation, originally established as a pulp mill in 1 ...

's N9 and Lumia devices, the HTC HD2, the Blackberry DTEK50,

Hero A hero (feminine: heroine) is a real person or fictional character who, in the face of danger, combats adversity through feats of ingenuity, courage, or Physical strength, strength. The original hero type of classical epics did such thin ...

, and Flyer and many other phones to repel fingerprint oil, which aids in preventing and cleaning fingerprint marks. Most "oleophobic" coatings used on mobile devices are

fluoropolymer A fluoropolymer is a fluorocarbon-based polymer with multiple carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and bases. The best known fluoropolymer is polytetrafluoroethylene under the brand name "Teflon, ...

-based solids (similar to

Teflon Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene, and has numerous applications because it is chemically inert. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a spin-off from ...

, which was used on the HTC Hero) and are both lipophobic and hydrophobic. The oleophobic coating beads up the oils left behind a user's fingers, making it easy to clean without smearing and smudging. This helps decrease the feasibility of a successful

smudge attack A smudge attack is an information extraction attack that Password cracking, discerns the password input of a touchscreen device such as a smartphone or tablet computer from fingerprint smudges. A team of researchers at the University of Pennsylvan ...

. In addition to being lipophobic or oleophobic, perfluoropolyether coatings impart exceptional lubricity to touch screens and give them a "slick feel" that eases their use. DIY products exist to restore or add an oleophobic coating to devices lacking one.

References

{{Reflist Chemical properties

Uses

See also

References