PDA

View Full Version : Solvents used in detailing products



togwt
08-12-2011, 02:41 AM
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.



Solvents are usually clear and colourless liquids and many have a characteristic odour. 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.



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.



Non-Paint Safe Solvents



• Aliphatic hydrocarbons (Mineral Spirits- V M & P, Naphtha)

• Aromatic hydrocarbons (Toluene, Xylene)

• Esters (Ethyl Acetate, Butyl Acetate)

• Ketone (Acetone, Methyl Ethyl Ketone (MEK))

• Use caution with chlorinated solvents



Chlorinated solvents



Are a large family of chemical compounds that, as its name implies contain chlorine, for example, carbon tetrachloride (carbon TET), trichloroethylene (TCE), or methylene chloride. They are used for a wide variety of commercial and industrial purposes, including degreasers, cleaning solutions, paint thinners, pesticides, resins, glues, and a host of other mixing and thinning solutions. Their chlorine-containing chemical structure helps them: to efficiently dissolve organic materials like fats and greases. Exposure from chlorinated solvents can be through absorption or through inhalation and skin contact.



Exposures can lead to short-term or long-term health effects, depending on the manner by which they entered your body and the amount of exposure. Short-term side effects may include dizziness, fatigue, headaches, and/or skin rashes. Long-term side effects may include chronic skin problems, and/or damage to the nervous system, kidneys, or liver.



Solvent Relative Strength Ratings (1/10)



• Toluene- 10/10

• Benzene- 9/10

• 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 damage



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; 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 (Stonerâ„¢ 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 scuffmarks 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 WD-40 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



Solvent-based silicone dressings; Dimethalsilicone (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



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 disrythmia

• 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®



WD-40® (water displacement) the long-term active ingredient is non-volatile, viscous oil which remains on the surface, providing lubrication and a moisture resistant protection. The oil is diluted with a volatile hydrocarbon solvent (Stoddard) to produce a low viscosity fluid, which uses a propellant (Butane) activated spray and thus displaces moisture.



The volatile hydrocarbon solvent evaporates, leaving the oil behind as a moisture resistant barrier. Use caution with this solvent; you`d be surprised at how silicones, solvents and oils migrate down into the paint matrix.









Use caution with solvents; you`d be surprised at how silicones, solvents and oils migrate down into the paint matrix.[/COLOR]



This is only a partial list of commonly used solvents for detailing