Solvents used in detailing products
Solvents [: (from the Latin solvere,
"loosen") is a liquid, solid, or gas that dissolves another solid,
liquid, or gaseous solute, resulting in a solution that is soluble in a certain
volume of solvent at a specified temperature.
The most common solvent in
everyday life is water. Most other commonly-used solvents are organic
(carbon-containing) chemicals. These are called organic solvents. Solvents
usually have a low boiling point and evaporate easily or can be removed by
distillation, leaving the dissolved substance behind. To distinguish between
solutes and solvents, solvents are usually present in the greater amount.
Solvents can also be used to extract soluble compounds from a mixture; the most
common example is the brewing of coffee or tea with hot water.
Solvent classifications
Solvents can be broadly
classified into two categories: polar and non-polar. Generally, the dielectric
constant of the solvent provides a rough measure of a solvent's polarity. The
strong polarity of water is indicated, at 0 °C, by a dielectric constant of 88.
Solvents with a dielectric constant of less than 15 are generally considered to
be nonpolar.
The dielectric constant measures the solvent's tendency to partly
cancel the field strength of the electric field of a charged particle immersed
in it. This reduction is then compared to the field strength of the charged
particle in a vacuum. Heuristically, the dielectric constant of a solvent can
be thought of as its ability to reduce the solute's effective internal charge.
Generally, the dielectric constant of a solvent is an acceptable predictor of
the solvent's ability to dissolve common ionic compounds, such as salts.
Solvents are usually clear
and colourless liquids and many have a characteristic odour. Most organic
solvents have a lower density than water, which means they are
lighter and will form a separate layer on top. The concentration of a solution
is the amount of compound that is dissolved in a certain volume of solvent. The
solubility is the maximal amount of compound that is soluble in a certain
volume of solvent at a specified temperature.
Common uses for organic solvents
are in dry cleaning (e.g. tetrachloroethylene), as paint thinners (e.g.
toluene, turpentine), as nail polish removers and glue solvents (acetone,
methyl acetate, ethyl acetate), in spot removers (e.g. hexane, petrol ether),
in detergents (citrus terpenes), in perfumes (ethanol), and in chemical
syntheses.
Density
Most organic solvents have a
lower density than water, which means they are lighter and will form a separate
layer on top of water. An important exception: many halogenated solvents like
dichloromethane or chloroform will sink to the bottom of a container, leaving
water as the top layer. This is important to remember when partitioning
compounds between solvents and water in a separator funnel during chemical
syntheses.
The reasoning for the use of
solvents for the removal of bituminous asphalt is that it dissolves it as a
means of removal, as opposed to rubbing it, tar is waterproof so water alone
will not remove it (although warm water will soften it). Asphalt is very sticky
and its presence on your paint means that harder particulate matter (dirt/grit)
has also stuck to it. By agitating or rubbing the dirt/grit that is contained
with the bituminous asphalt will cause surface marring or possibly scratching,
dissolution alleviates any potential surface damage.
Solvent
Expansion
The main risks associated with using solvents; relate to the
effects of solvent on the organic binder system that holds the paint together.
The more acute element of risk is that of expansion of the paint through
sorption of solvent. The polymerised urethanes dried oil network may not be
truly soluble, but the polymer network may expand by sorption of solvent or
concentrated isopropyl alcohol molecules and sometimes silicone.
Depending on the degree of expansion, the paint will be more or
less softened and its capacity to bind the pigment particles may be affected.
In the swollen condition, there is a risk that pigment may be removed from the
paint through the (kinetic energy (friction heat) of a foam pad and rotary
action (twisting) causing the paint to tear.
Safe Solvent
Solvents are used for
chemical cleaning, and as a carrier system, it also makes products workable and
to provide spread ability, as is the case with Carnauba wax, which in its
natural state is rock hard.
The low surface tension of
silicones is sometimes added to solvents to improve the wetting ability and to
improve the surface contact. Solvents require an aerobic cure (exposure to air)
to allow them to evaporate (outgas); some solvents contain formaldehyde, which
dissolves both natural rubber and synthetic compounds, and some contain
petroleum distillates specifically hydrocarbon and oxygenated solvents, which
represent most of the total organic solvents used.
If you want to safely
degrease your vehicles use an environmentally safe product that can also clean
your paint, wheels, tires, engine bay, wheel wells, trim and etc
·
P21S®® Total Auto Wash
·
Optimum Power Clean All Purpose Cleaner Degreaser
·
Wurth Engine Cleaner and Degreaser
·
Simple Green® Aircraft & Precision Cleaner
·
ValuGard
New Car Prep
·
d-Limonene
- Chemical Formula: C10H16
Non-Paint
Safe Solvents
·
Aliphatic hydrocarbons (Mineral Spirits- V M & P, Naphtha)
·
Aromatic hydrocarbons (Toluene, Xylene)
·
2-Butoxyethanol or Butyl Cellosolve
·
Esters (Ethyl Acetate, Butyl Acetate)
·
Ketone (Acetone, Methyl Ethyl Ketone (MEK)
Use caution with chlorinated solvents
Solvent
Relative Strength Ratings (1/10)
·
Toluene-
10/10
·
Benzene-
9/10
·
Butyl
(i-butyl alcohol) - 8/10
·
Butanone
(methyl ethyl ketone or MEK) - 7/10
·
Acetone
- 6/10
·
Denatured
alcohol (Ethanol or Methylated Spirits) –
5/10
·
Mineral
Spirits(Stoddard solvent) – 4/10
·
Isopropyl
alcohol – 3/10
·
Ethylene
glycol – 2/10
·
Distilled
water – 1/10
Offered as a guide only to
show relative strength of commonly used solvents; all chemical cleaning is an
exercise in risk/benefit analysis. Even with the mildest cleaning agent, such
as distilled water, there will always be some risk of damaging
Organic solvents
Can be classified by
chemical structure, for example water is a solvent, but is inorganic. Solvents
provide solubility for the other ingredients, dependent upon the type of
solvent used will determine the product's drying time.
Use a safe solvent; d-Limonene
(3M Citrus Base Spray Adhesive Remover or P21S
Total Auto Wash) that does not contain any harmful components (butyl, heptanes
or xylene or hydrocarbon aliphatic solvents) With all cleaning products
(especially solvents) always test a small inconspicuous area first to ensure it
won't discolour, stain or etch the surface, and ensure that the pH of the
product is suitable for the material After the paint surface has been subjected
to a chemical cleaning its protective layer (s) have been removed and the paint
surface left without protection, so it is very important that a wax or polymer
protection be applied immediately.
3M Citrus Base Spray
Adhesive Remover – a citrus-based, solvent-free adhesive remover leaves surfaces
clean and dry with no residue. Removes marker graffiti from white boards and
tape residue from masking, foam or duct tape. Clean, fresh citrus scent - not
recommended for use on plastic
There are three main types:
1. Oxygenated Solvents- alcohols, glycol ethers, ketones, esters,
and glycol ether esters. Oxygenated solvents are synthesized from other
chemicals to form the desired solvent. Those solvents are typically of a high
purity with specifications ranging from 99.0% to 99.9% purity.
2. Hydrocarbon Solvents (Petroleum Distillates) - aliphatic
(include methane, propane, and kerosene, they are flammable and may be
explosively flammable).
3. Aromatic hydrocarbons- (are the most toxic compounds found in
petroleum products and include such substances as para-xylene (benzene,
toluene, ethyl benzene, and xylene), which are all volatile organic compounds
(VOC) (See also Petroleum Distillates)
Notes- when
using solvents always use Nitrile medical gloves (usually the blue or purple
ones) if you are going to be using them for any length of time.
A safe solvent that does not
contain any harmful components (heptanes or xylene or hydrocarbon aliphatic
solvents (Stoner™ Tarminator or Valuguard
New Car Prep, simply emulsifies and dissolves the bituminous asphalt / tar
/grease when you spray it directly on the paint film surface It is important
not to leave a solvent based chemical on the paint finish longer than is
necessary. Simply apply to the affected area, allow sufficient dwell time, and
carefully wipe off, you may have to apply it three or four times allowing
plenty of "dwell time" between applications.
Other uses –it
can also dissolve a variety of oil and petroleum based products, it's safe to
use on all types of paint, plastics, synthetic fibres, carpet and upholstery.
If used on vehicle paintwork
re-apply a protect rant after use it will dissolve chewing gum and adhesives.
Use to de-tar wheel rims after cleaning, will also remove shoe scuffs marks from
vinyl trim, and can be used to remove tree sap or fuel stains from paint
surfaces.
With all cleaning products
(especially solvents) always test a small inconspicuous area first to ensure it
won't discolour, stain or etch the surface, and ensure that the pH of the
product is suitable for the material
After the paint surface has
been subjected to a chemical cleaning its protective layer (s) have been
removed and the paint surface left without protection, so it is very important
that a wax or polymer protection be applied immediately.
Notes- Use caution if you use WD40 as it
contains strong hydrocarbon (aliphatic) solvents, which may cause the paint
surface to become clouded (opaque) or compromise non-neoprene rubber, it is
also highly flammable (easily ignited by heat, sparks or flames) Don’t let it
drip onto the brake pads as they will become ineffective and / or grab and
squeal
(MSD)
–http://www.wd40.com/Brands/pdfs/msds...aerosol.us.pdf
One of the most widely used
solvent in detailing -Isopropyl alcohol
[Anhydrous Isopropyl alcohol [Molecular formula C3H8O]
for all-purpose cleaning, isopropyl alcohol, is a colourless liquid with a
pleasant odour, and is highly flammable. A miscible clear fluid, Flash
point 53.0F (12.0C) closed cup]
Be cognizant
that modern paint systems are porous, so be cautious as to what solvents you
use. Isopropanol (IPA) is a moderately polar solvent - Xylene and
Toluene are non-polar strong solvents, which can etch the paint surface
Isopropyl alcohol (IPA) is available as 70 to 95 percent ethanol, or ethyl
alcohol, along with water, acetone, methyl isobutyl ketone, and additives to
give it a bitter taste some rubbing alcohol includes perfumes or artificial
colouring. The term "rubbing alcohol" has become a general
non-specific term for either isopropyl alcohol (isopropanol) or ethyl alcohol
(ethanol) Rubbing-alcohol products can leave a residue behind It is prepared from a special denatured alcohol
solution and contains 97.5-100% by volume of pure, concentrated ethanol (ethyl
alcohol) or isopropyl alcohol (IPA)
For less dense (soft) clear coat,
the lower rate of isopropyl alcohol dilution (1:10) is recommended; conversely
denser (hard) clear coats should use a higher dilution (1:25); as you increase
the dilution rate of isopropyl alcohol its paint softening effect drops
exponentially.
Isopropyl alcohol (IPA) is a fast evaporating
solvent and at higher ambient temperatures will filly evaporate (flash) within
~30 minutes at higher temperatures. At greater dilution percentages it will
evaporate more slowly, bear this in mind in warmer environments.
A recommended isopropyl alcohol (IPA) dilution of
1:10 to 1:4 ratios (10-25%) in distilled water as a ‘safe’ surface Wipedown
cleaning solution. The reason for this wide range is due to the variations in
the clear coat paint systems. My personal recommendation would be a 10% <
dilution of Isopropanol (IPA) / distilled water solution. Be cognizant that a
stronger (less diluted) solution of IPA can stain and even soften some clear
coat paints, causing it to delaminate (wrinkle).
Isopropyl alcohol (IPA) and or
other solvents will permeate the paint, causing both temporary softening and
some swelling as well as paint delamination or staining Dependant on the
solvent (strength) used and how much heat is entailed, the amount of swelling
varies. (See also “Paint (Solvent /
Alcohol) Swelling”)
Isopropyl
alcohol (IPA) is readily available and
like acetone, it dissolves a wide range of non-polar compounds. It is also
relatively non-toxic and evaporates quickly. Thus it is used widely as a
solvent and as a cleaning fluid
Mineral oil can be used to clean heavier oil
stains by diluting and liquefying the other oils, rendering the oils more
accessible to detergents.
Likewise, it can be employed to
de-gum, to remove adhesive residue left by adhesive tape. Be cognizant that
while it can be used as a solvent cleaner it can leave a residue, which is undesirable for paint cleaning
applications.
Denatured alcohol (or Methylated spirits) - is ethanol that has additives to make it more
poisonous or unpalatable, and thus, undrinkable. Do not use denatured
alcohol as a substitute for Isopropyl
alcohol (IPA)
An analogy: bituminous asphalt concrete (tar) is
highly non-polar and IPA is not. Like
dissolves like is a good general rule.
Use caution if using paint thinner
/ strong solvent as there is a possibility that it can have detrimental long
term effects, which cause the paint matrix to fail over time leaving a dull
area that has a similar appearance to strikethrough, which cannot be corrected
Solvent-based silicone
dressings; Dimethyl Silicone (DMS) usually a clear greasy liquid, which leaves a
never-dry gloss film, most contain petroleum distillate solvents.
Silicone is inert, it’s the
solvent that damages the rubber, as it acts as a cleaning agent, as a result,
the tyre begins to crack and rot. After the antiozonant works its way to the
outside of the tyre and is exposed to the ozone in the air, it turns brown.
The technical term for this
effect is blooming, which then removes the elasticity from vinyl, rubber and
paint; causing them to evaporate out of the substrate, expelling the rubber
additives to the tyres surface and could result in premature drying and
cracking, leaving behind a dry inflexible surface. Many tyre manufacturers
(Goodyear, Michelin, etc) have issued technical service bulletins advising
against the use of tyre dressings containing DMS silicone.
The difference between water
and solvent based is in the carrier system used. Solvent based products use a
hydrocarbon silicone to suspend the product. When you apply it, the solvent
evaporates leaving the dressing's active ingredients (silicone oil) behind;
this type of silicone leaves a high gloss shine and will repel water longer but
it is non-biodegradable. Most high gloss products are based upon (DMS) for
vehicles fitted with ceramic brakes and / or pads PDS silicone products are not
recommended as it can contaminate the pads and render them ineffective
de-Limonene
In general, the standard pH test assumes an aqueous solution
(water based). The pH of water immiscible solvents (Limonene) cannot be
measured using typical methods. The
chemistry of organic solvents prevents accurate measurements using the 0-14
scale and standard electrodes.
A relative pH measurement is obtained by mixing the oil with an equal
volume of neutralized water (preferably purified with no dissolved salts). The pH of the water should be measured before
mixing. Mix the water and oil for
approximately 5 minutes and then allow the phases to separate.
Measure the pH of the water phase again. In principle, the pH of the water is now a
reflection of the pH of the oil.
This is not a precise value, but can be used as estimation for
most applications. Due to the nature of
citrus processing, Limonene typically contains residual amounts of anhydrous
acids and thus yields an acidic relative pH value of 10.5 – 11.5
As a
straight solvent, its flash point is 110.0F (43.0C) Limonene
can replace a wide variety of products, including mineral spirits, methyl ethyl
ketone, acetone, toluene, glycol ethers, and of course fluorinated and
chlorinated organic solvents. As with most organic solvents, Limonene is not
water soluble, so it can be used in the typical water separation units. With a
KB value of 67, Limonene has solubility properties close to that of CFC,
indicating that it is a much better solvent than a typical mineral spirit.
Straight Limonene can be used as a wipe cleaner
Chemical Name: Benzene
Synonyms: Benzol,
Cyclohexatriene
• Effects on Vehicle: Paint
streaking, damage
• Health Effects:
Carcinogenic
• Found In: Solvents,
Compounds
Chemical Name:
Toluene
Synonyms: Toulon,
Methylbenzene
• Effects on Vehicle: Paint
streaking and damage
• Health Effects:
• Central nervous system
depression, cardiac
• Found In: Solvents,
Compounds
Chemical Name:
m-Xylene
Synonyms: Meta-Xylene, 1,
3-Dimethylbenzene, m-Xylol
• Effects on Vehicle: Paint
streaking and other damage
• Found In: Solvents,
Compounds
Miscellaneous
White spirit
(Stoddard solvent) is a paraffin-derived
clear, transparent liquid which is a common organic solvent used in painting
and also used an extraction solvent, as
a cleaning solvent, as a degreasing solvent and as a solvent in aerosols,
paints, wood preservatives, lacquers, varnishes, and asphalt products. White
spirit is the most widely used solvent in the paint industry. Its paint
thinning properties enable brushes to be properly cleaned (by preventing the paint
from hardening and ruining the bristles) and therefore enabling them to be
re-used. There are three different grades of white spirit: .T1 Low flash point
(21-30.0C) T2 Medium flash point (31-54.0C) and T3 High
flash point (55.0C)
Mineral spirits
(Mineral Oil) is
a petrochemical based product, a clear, colourless, oily liquid that is a
by-product of the distillation of petroleum that can be used to clean heavier
oil stains by diluting and liquefying the other oils, rendering the oils more
accessible to detergents. It has a high refractive index and is sometimes used
in car care products. Likewise, it can be employed to remove adhesive residue
left by adhesive tape.
It can be used
as a cleaner and solvent but it can leave a residue, which is undesirable for
paint cleaning applications. Other uses, as a prevention to stop chopping
boards cracking and , as a rust prevention for steel A clear fluid , Flash
point 107.0F (41.0C) closed cup
Mineral turpentine
Also known as
turpentine substitute, is an inexpensive petroleum-based replacement for the
vegetable-based turpentine. It is commonly used as paint thinner for thinning
oil-based paint and cleaning brushes, and as an organic solvent in other
applications
Rocket
Chemical Company WD-40® (Water displacement)
Is
the trademark name of a widely-available water-displacing spray. The long-term active ingredient is
non-volatile, viscous oil which remains on the surface, providing lubrication
and protection from moisture. This is diluted with a volatile hydrocarbon to
give a low viscosity fluid which can be sprayed and thus get into crevices. The
volatile hydrocarbon then evaporates, leaving the oil behind
Use caution when using solvents; you'd be surprised at how silicones, solvents and oils
migrate down into the paint matrix.
This is only a partial list of commonly used solvents for
detailing
Bibliography
1
1. Mechanism and Theory in Organic Chemistry - Lowery, T.H. and Richardson, K.S.
2. An introduction to Physical Organic Chemistry - Kosower, E.M.
2. An introduction to Physical Organic Chemistry - Kosower, E.M.
I
would like to think that these articles become an asset to anyone who is new to
detailing and to professionals alike, as well as industry experts who seek to
advance their knowledge.
I hope the above article was
informative. By having some understanding of the ‘What’ and ‘Why’ as well as
the ‘How’ along with a little science to help you understand how the chemicals
we use react, you can achieve the results you desire.
I would
appreciate it if you would share this article as it helps other detailers
further their knowledge.
Questions and/ or constructive comments are always
appreciated.
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