Listing description
Linseed oil, also known as flaxseed oil, is a colourless
to yellowish oil obtained from the dried, ripened seeds of the flax plant (Linum usitatissimum). The oil is obtained bypressing, sometimes
followed by solvent extraction. Linseed oil is a drying oil, meaning it
can polymerize into a solid form. Due to its polymer-forming properties,
linseed oil can be used on its own or blended with combinations of other oils, resins or solvents as an impregnator, drying oil finish or varnish in wood finishing, as a pigment binder in oil paints, as aplasticizer and hardener in putty, and in the manufacture of linoleum. Linseed oil
use has declined over the past several decades with increased availability of
synthetic alkydresins—which function similarly but resist
yellowing.
Detailed description
Linseed oil is an edible oil in demand as a nutritional supplement, as a source of α-Linolenic acid, (an omega-3 fatty acid). In parts of Europe, it is traditionally eaten with potatoes
and quark. It is regarded as a delicacy due to its hearty
taste, which enhances the flavour of quark, which is otherwise bland.[2]
Chemical aspects
Linseed oil is a triglyceride, like other fats.
Linseed oil is distinctive for its unusually large amount of α-linolenic acid, which has a distinctive reaction with oxygen in air.
Specifically, the fatty acids in a typical linseed oil are of the following
types:[3]
·
The triply unsaturated
α-linolenic acid (51.9-55.2%),
Having a high
content of di- and triunsaturated esters, linseed oil is particularly
susceptible to polymerization reactions upon exposure to oxygen in air. This polymerization,
which is called drying, results in the rigidification of the
material. The drying process can be so exothermic as to pose a fire hazard
under certain circumstances. To prevent premature drying, linseed oil-based
products (oil paints, putty) should be stored in air-tight containers.
Uses
Most
applications of linseed oil exploit its drying properties, i.e., the initial
material is liquid or at least pliable and the aged material is rigid but not
brittle. The water-repelling (hydrophobic) nature of the resulting hydrocarbon-based material is
advantageous.
Paint binder
Linseed
oil is a common carrier used in oil paint. It can also be
used as a painting medium, making oil paints more fluid, transparent and
glossy. It is available in varieties such as cold pressed, alkali refined, sun
bleached, sun thickened, and polymerised (stand oil). The introduction of
linseed oil was a significant advance in the technology of oil painting.
Putty
Traditional
glazing putty, consisting of a paste of chalk powder and linseed
oil, is a sealant for glass windows that hardens within a few weeks of
application and can then be painted over. The utility of putty is owed to the
drying properties of linseed oil.
Wood finish
When
used as a wood finish, linseed oil dries
slowly and shrinks little upon hardening. Linseed oil does not cover the
surface as varnish does, but soaks into the (visible and microscopic) pores,
leaving a shiny but not glossy surface that shows off the grain of the wood. A
linseed oil finish is easily repaired, but it provides no significant barrier
against scratching. Only wax finishes are less protective. Liquid water
penetrates a linseed oil finish in mere minutes, and water vapour bypasses it
almost completely.[5] Garden furniture treated with linseed
oil may develop mildew. Oiled wood may be yellowish and is likely to
darken with age. Because it fills the pores, linseed oil partially protects
wood from denting by compression.
Linseed
oil is a traditional finish for gun stocks, though very fine finish may require
months to obtain. Several coats of linseed oil is the traditional protective
coating for the raw willow wood of cricket bats; it is used so
that the wood retains some moisture. New cricket bats are coated with linseed
oil and knocked to perfection so they last longer.[6] Linseed oil is also
often used by billiards or pool cue-makers for cue shafts, as a
lubricant/protectant for wooden recorders, and used in place of epoxy to seal modern wooden surfboards. Additionally, a luthier may use linseed oil
when reconditioning a guitar, mandolin, or other stringed instrument's
fret board; lemon-scented mineral oil is commonly used for
cleaning, then a light amount of linseed oil (or other drying oil) is applied
to protect it from grime that might otherwise result in accelerated
deterioration of the wood.
Gilding
Boiled
linseed oil is used as sizing in traditional oil gilding to adhere sheets of
gold leaf to a substrate (parchment, canvas, Armenian bole, etc.) It has a
much longer working time than water-based size and gives a firm smooth surface
which is adhesive enough in the first 12–24 hours after application to cause
the gold to attach firmly to the intended surface.
Linoleum
Linseed
oil is used to bind wood dust, cork particles, and related materials in the
manufacture of the floor covering linoleum. After its
invention in 1860 by Frederick Walton, linoleum, or
'lino' for short, was a common form of domestic and industrial floor covering
from the 1870s until the 1970s when it was largely replaced by PVC ('vinyl') floor
coverings.[7] However, since the
1990s, linoleum is on the rise again, being considered more environmentally
sound than PVC.[8] Linoleum has given
its name to the printmaking technique linocut, in which a relief
design is cut into the smooth surface and then inked and used to print an
image. The results are similar to those obtained by woodcut printing.
Nutritional supplement and food
Flax
seed oil is easily oxidized, and rapidly becomes rancid, with an unpleasant odour, unless refrigerated. Even when kept
under cool conditions, it has a shelf life of only a few weeks.[9][dubious discuss] Oil with an unpleasant
or rancid odor should be discarded. Oxidation of flax seed oil is a major
commercial concern, and antioxidants may be added to prevent rancidification.[10] Linseed oil is not
generally recommended for use in cooking, yet one study does show that the alpha linolenic acid (ALA) while bound in
flaxseed was found to be stable for cooking. When bound to flaxseed ALA can
withstand temperatures up to 350 degrees F (176.67 C) for two hours.[11]
Food-grade
flaxseed oil is cold-pressed, obtained without solvent extraction, in the
absence of oxygen, and marketed as edible flaxseed oil. Fresh, refrigerated and
unprocessed, linseed oil is used as a nutritional supplement and is a traditional
European ethnic food, highly regarded for its hearty taste. It contains the
highest level of the omega-3 fatty acidALA among vegetable oils.[12] Regular flaxseed oil
contains between 52% and 63% ALA (C18:3 n-3).
Plant breeders have developed flaxseed with both higher ALA (70%) and very low
ALA content (< 3%).[13] The USFDA granted
generally recognized as safe (GRAS) status for high alpha linolenic flaxseed
oil.[14]
Nutrient content[edit]
|
Typical fatty acid content
|
||
|
6.0
|
4.0–6.0
|
|
|
2.5
|
2.0–3.0
|
|
|
0.5
|
0–0.5
|
|
|
-
|
0–0.5
|
|
|
19.0
|
10.0–22.0
|
|
|
-
|
0–0.6
|
|
|
24.1
|
12.0–18.0
|
|
|
47.4
|
56.0–71.0
|
|
|
Other
|
0.5
|
-
|
Per
1 tbsp (14 g)
·
Calories: 126
Flax
seed oil contains no significant amounts of protein, carbohydrates or fibre.
Additional uses
·
Animal care products
·
Industrial lubricant
Modified linseed oils
Stand oil
Stand
oil is generated by heating linseed oil near 300 °C for a few days in the
complete absence of air. Under these conditions, the polyunsaturated fatty
esters convert to conjugated dienes, which then undergo Diels-Alder reactions, leading to crosslinking. The product, which is highly viscous,
gives highly uniform coatings that "dry" to more elastic coatings
than linseed oil itself. Soybean oil can be treated
similarly, but converts more slowly. On the other hand, tung oil converts very quickly,
being complete in minutes at 260 °C. Coatings prepared from stand oils are
less prone to yellowing than are coatings derived from the parent oils.[19]
Boiled linseed oil
Today,
"boiled linseed oil" refers to a combination of raw linseed oil,
stand oil (see above), and metallic dryers (catalysts to accelerate drying).[19] In Medieval times,
linseed oil was boiled with lead oxide[20] (litharge) to give a
product called boiled linseed oil. The lead oxide forms lead "soaps"
(lead oxide is alkaline) which promotes hardening (polymerisation) of linseed
oil by reaction with atmospheric oxygen. Heating shortens its drying time.
Spontaneous combustion
Rags
soaked with linseed oil stored in a pile are considered a fire hazard because
they provide a large surface area for oxidation of the oil, and the
oil oxidises quickly. The oxidation of linseed oil is an exothermic reaction, which accelerates as the temperature
of the rags increases. When heat accumulation exceeds the rate of heat
dissipation into the environment, the temperature increases and may eventually
become hot enough to make the rags spontaneously combust.[21][dubious discuss]
In
1991, One Meridian Plaza, a high rise in Philadelphia, was severely
damaged and three firefighters perished in a fire caused by linseed oil-soaked
rags.[22] In 2011, a garage inSacramento also caught fire due
to the spontaneous combustion of linseed oil-soaked rags.[23] In 2014, the Diamond
Head home of Hawaii 5-0 actor Alex O'Loughlin was damaged in a
similarly started fire.[24]
When
the mummy of King Tutankhamen was examined by Howard Carter, he described the
mummy as a "charred wreck". Investigation of the mummy by
archeologist Chris Naunton revealed that, with the hasty preparations for the
burial, after the body was sealed in its tomb, the linseed oil and linen used
in elements of the mummification process resulted in spontaneous combustion
that charred the body.
PRICE
$27.28/KG
For more information:
mobile: +2348039721941
contact person: emeaba uche
website: www.franchiseminerals.com
e-mail: emeabau@yahoo.com
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