Friday, 24 April 2015

Silica Coating Application Methods

Automotive paint coatings have been around for some time now and there are some unique coatings available as the market begins to grow.  When coatings were first introduced, their marketing model was to make them available through certified professionals who were educated on their somewhat complicated application. But to reach a larger market they have become much more user-friendly, with many mfg. adding new products making their application within the experience level of many more detailers

There are a wide range of paint coatings available, and each one is very unique. They are sub-micron particles that form a clear thin film of tightly packed nano particles that bond to your paint and become the new functional surface. The particles are up to a 1000 times denser which makes for an ultra-durable hard wearing surface. Technically most detailing product particulates are not nanometer in size, although they are extremely small, as the term ‘nano’ adequately describes. Single-component coatings interlace on a molecular basis and form an extremely durable protective layer on the paint surface provided they are applied properly.

The significance of a nano-coating is its micro sized particles that can form a very tight bond with the surface of most materials; including glass, paint, plastic, rubber, aluminium, chrome, stainless steel and fabrics. These materials will have surface imperfections i.e. peaks and valleys, micro-fissures when viewed under high magnification. These undulations allow a nano-coating polymer to form a tight molecular bond (much like a printer’s powdered ink when poured over paper that has writing indentations on it) with the surface it’s applied to.

A coating system forms a thin crystalline film comprised of hard dense particles turning the surface structure into an ultra-durable surface. Sealing a surface means applying micro particles onto the surface, these treated surfaces become hydrophobic and therefore highly water repellent, which enables less effort during the cleaning stages, coatings also impart surface energy (38mN/m surface tension or higher) and optimum protection to the paintwork, glass, alloys, fabric and trim.
First cost range from approximately 50 to 105 USD plus, which would cover 1-2 (with experience in their application) vehicles per bottle

Their marketing claims a coating thickness of between 2 – 5µ (microns) and a pencil hardness of 9H, they are acid resistant with durability measured in years. To obtain this type of durability, the surface must be free of any oils, silicones, and waxes.  Coatings are optically clear, and will magnify any surface imperfections. The surface needs to be clinically clean and as swirl free as possible.
Coatings will outlast any other type of paint protection and it requires an abrasive and a machine polisher to remove them. They will also provide a durable finish and they will prove to be cost effective in the long run

Roll off - dirt particles with a reduced contact area are encapsulated by water droplets and are easily cleaned off the surface. If a water droplet rolls across such a contaminated surface the adhesion between the dirt particles and the water droplet is very much reduced and the dirt is easily removed from the surface
Paint sealants compared to Coatings

Automotive paint surfaces are porous and contain microscopic peaks and valleys, much like the profile of a mountain range. These irregularities are known as capillary structures; there may be millions of these defects per square inch. Contaminants such as fine dirt, minerals, and pollutants are drawn into the voids where they are extremely hard to remove.

Paint sealants are synthetic products designed for long-term paint protection and easy application. They are composed mainly of amino functional polymers, which last longer than any natural wax and are highly resistant to the elements. Synthetic liquid waxes are another way of describing paint sealants. The main benefit of a paint sealant is their durability compared to a wax, polymer-based sealants will last anywhere from 3 to 6 months.

A coating is applied to a clean surface that surface takes on properties that are virtually identical to hardened glass. It is chemically inert and will not react with the base material. In other words, dirt will not bond to the treated surface, thereby reducing soiling and organic staining. Acid rain and other chemical compounds easily wash off, significantly reducing the hydroscopic nature of surfaces exposed to industrial or environmental pollution.

You can verify statement regarding the coating thickness by using a paint thickness gauge, but be cognizant that most thickness claims are based on a spray application of the product. Any installer with a PTG can verify the thickness of his application, wiping on and other variables may reduce the thickness,

Silica Coating consist of four chemicals – Silicon (Si), Siloxane (H(OSiH2)n OH), Silane (SiH4 ) and Silazane(a silicone compound), once formulated they become Silicon Dioxide (SiO2) they are marketed under various brand names:  AQuartz  is an inorganic silica / silicon dioxide, G|techniq is an inorganic silicate crystallization compound, Nanolex is an  inorganic, solvent-based nanostructure coating, Opti-Coat™ is a polymer-based (SiC)  carbide ceramic coatings. DuPont's SupraShield™, PPG's Optech™ and CeramiClear™ are all inorganic silica automotive paint coatings.

Be cognizant that there are many glass coats in the market today and many of them can  be traced back to one or two suppliers

Silica coating are a clear liquid in a molecular form that is held in a polymer solvent carrier system. This silica is aerobic (hardens on contact with air) and becomes glass. Multi-chemical component coatings interlace on a molecular basis and form an extremely durable protective layer on the paint surface provided they are applied properly. These coatings are chemically inert and are highly resistant to a range of chemicals both acid to Ph. 2.0 and alkali to Ph. 13.5  acid, they also offer resistance to solvents, and they are very durable and capable of obtaining a surface thickness of Mils (µ (microns) to be verified

When a silica coating is applied to a clean surface, that surface takes on properties that are virtually identical to hardened glass. It is chemically inert and will not react with the base material. In other words, dirt will not bond to the treated surface, thereby reducing soiling and organic staining.
Silica is highly acid resistant and is not affected by acid rain, bird excrement and other chemical compounds, which easily wash off, significantly reducing the hydroscopic nature of surfaces exposed to industrial or environmental pollution.

The paint surface is porous and contains microscopic peaks and valleys, much like the profile of a mountain range. These irregularities are known as capillary structures. Contaminants such as fine dirt, minerals, and pollutants are drawn into the voids where they are extremely hard to remove. Capillary structures also provide microbes and bacteria with an excellent place to grow and multiply.

The silica coating fills the capillary structures, which produces a smooth flat hydrophobic surface. (A hydrophobic surface is one that repels moisture.) In contrast, a hydrophilic surface is one that absorbs moisture. The potential of a surface to absorb or repel moisture is based on many factors, including: temperature, relative humidity, material homogeneity, and static electricity. Surface roughness is also a major factor; the rougher the surface, the higher the spreading rate or attraction for water. The smoother the surface, the more repellent it is to moisture.

Some formulations of Liquid glass contain titanium dioxide for extra shine without affecting durability. These micro-particles of titanium dioxide reflect light of specific wavelengths, producing an instant luminous shine and gloss. Titanium dioxide is sensitive to photocatalyzation and produces traces of active oxygen when exposed to ultra violet (UV) radiation. This effect helps the coating to prevent the attachment of contaminants to the paint. This means that, in most instances, environmentally damaging cleaning chemicals are not needed.

Protection from Potential Health Hazards

Wear appropriate personal protective clothing to include: Safety glasses, Hearing and Repertory protection

Silicosis happens by breathing the dust particulates of silica (glass), which cut and scar the lungs, causing damage, which results in diminished lung capacity. So where does the silicon dioxide enter into this equation as a safe product to breathe when applied as a spray? 

Liquid glass is actually a mixture of caustic soda, quartz sand, and water are prepared in a mixing tank, then fed into a reactor, where steam is introduced. The reaction is (n SiO2 + 2 NaOH → Na2O•nSiO2 + H2O). Sodium silicate is spherical silica in a liquid state, which essentially means ‘liquid glass’ crystals which are smooth and round instead of sharp and pointed.

Because there are no sharp edges to damage lung tissue it is relatively safe to breath. But why would we think it is safe to fill our lungs with round glass any more than with jagged sharp glass particles? 
Do the lungs have the ability to process and get rid of the ‘spherical’ shapes through the blood stream? 

Is ‘liquid silicon dioxide’ really ‘colloidal silica,’ or is it ‘sodium silicate’? 

Silicon dioxide = SiO2 and Sodium silicate = Na2SiO3. Colloidal silica is simply the liquid spherical shape of silicon dioxide while sodium silicate is silicon dioxide with an added salt element (Na). Both products are derived from the second most abundant element on Earth – sand.

I would strongly suggest you do not breathe it in but use the appropriate personal protection. If you were to examine the urethane clear coat with high-performance electron- microscope, you would see lots of fissures or micro holes. Nano sized silica glass particles penetrate these fissures to form a mechanical anchor with the clear coat, creating a durable finish that won't fracture

Respiratory Protection (N95): Materials such as aluminium oxide (Aluminium oxide is on EPA's TRI list if it is a fibrous form) or silicon carbide (Nuisance particulate-Accumulation in lungs) used in polishes and compounds, and powdered fillers Crystalline silica (polishes and compounds) poses a serious inhalation hazard because it can cause silicosis and Isocyanate clear coat residue represent a hazard to your lungs and may cause respiratory distress. Use a NIOSH-approved half face respirator equipped with a combination filter cartridge should be worn while using them
 Consult the current 3M Respiratory Selection Guide for additional information or call 1-800-243-4630 for 3M technical assistance

Modesta Silica Products

P-01A and BC-04 Nano-Titanium Glass coating - is definitely a worthy investment if your vehicles appearance is important to you. An advanced and very unique glass coating, it forms a highly durable, clear hard glass layer on automotive paints.
BC-01 High-gloss Water-repellent Glass Coating - combines special oligomer content with outstanding water-repelling properties to create a special glass layer with high durability. A two-component glass coating that produces instant luminous shine and gloss.  The presence of a special type of Silane in the first component triggers a chemical reaction with the second component, creating long-lasting water-repellent characteristics and preventing adhesion of raindrops and water spots.  When completely cured, the coating membrane is composed of the same silicon structure as glass, forming a durable protective glass layer. 

Eliminating the risk of scratches should not the only objective in protecting automotive paints. A major cause of paint damages, such as loss of gloss and dullness is paint oxidation. This process can be slowed by isolating the paint surface from the air. Although this can be achieved with conventional coating agents and wax, the oils and fats contained in such materials oxidize easily, and in turn oxidize anything they come into contact with. 

Once oxidized, these paint protection agents can often accelerate the degradation of paint rather than protect it. The inorganic nature of the BC-03 glass coating makes it fully resistant to oxidation and therefore more suitable for protecting paint. The hard physical barrier it creates also prevents paint from coming into contact with the air and acts as a strong anti- scratch protectant.

BC-03 Pure Glass Coating- does not crack, bubble, flake, peel, delaminate, detach or discolour at temperatures up to 700 °C. This new formula combines pure liquid glass and titanium dioxide for extra shine without affecting durability. It contains 0.16µm particles of titanium dioxide that reflect light with specific wavelengths, producing an instant luminous shine and gloss. Titanium dioxide is sensitive to photo catalyzation and produces traces of active oxygen when exposed to ultra violet (UV) radiation. This effect helps the coating to prevent the attachment of contaminants to the paint.

BC-04 Nano-Titanium Glass Coating – a new formula coating that combines the best advantages of the original Pure Liquid Glass coatings and highest quality nano-grade titanium. This combination creates a deeper shine and better reflections on the paint. A significantly prolonged working time also allows easier and safer application.  The inorganic nature of the coating makes it fully resistant to oxidation. The hard physical barrier it creates also prevents paint from coming into contact with air and acts as an anti-scratch protectant. Capable of withstanding temperatures of up to 900 °C.  Layer thickness: 2-3μm (paint thickness gauge (PTG) measurable)

BC-05 Advanced Water Repellent Glass Coat
Modesta BC-05 is a unique glass coating based on a three-dimensional molecular frame. It forms a highly durable clear hard glass layer on automotive paints. BC-05 produces a deep shine and helps to protect the paint from all kinds of damage including wash-induced damages, scratches, oxidation, sap, watermarks, salts, acids and even permanent ink and paints. Its strong water-repellent properties also promote the self-cleaning effects. Used stand-alone as a sealant, BC-05 produces a unique kind of gloss called the "candy-like" gloss. If combined with the P-01A primer this effect is even deeper as the layers of both products are combined to a single coat. It can be applied even to the most advanced and sophisticated paints, such as Nissan Scratch Shield, Lexus' self-restoring coat and Mercedes ceramic paint.
Product Application
Be cognizant that for a coating product to reach its full potential; that is to say the correct contact angle, durability and optimum cross-linking it imperative that you provide a ‘clean’ surface. Prior to application both above and sub-surfaces should be decontaminants, polishing lubrication (oils, polymer (silicones) and wax) system should be removed

Surface preparation
1.   Clean surface by using a professional panel wipe (Spies Hecker 7010 Silicone Remover) as a post-paint surface cleaner. Apply to the towel first (not directly to the surface) and remove with another clean towel.  As with all coating products, the key to success is proper surface preparation prior to application

Quartz sand (silica) Inhaling finely divided crystalline silica dust in very small quantities (OSHA allows 0.1 mg/m3) over time can lead to silicosis, bronchitis, silica polishes and compounds are carcinogenic, as the dust becomes lodged in the lungs and continuously irritates them, reducing lung capacities. (Silica does not dissolve over time.) 
Recognizing that very small, respirable silica particles are hazardous, the Occupational Safety and Health Administration (OSHA) regulation 29 CFR 1926.55(a) requires construction employers to keep worker exposures at or below a Permissible Exposure Level (PEL) of 0.1 mg/m3,
Use the appropriate personal protection equipment (PPE) an approved mask (Consult the current 3M Respiratory Selection Guide for additional information or call 1-800-243-4630 for 3M technical assistance) nitrile gloves and safety glasses as a minimum

My preferred application method is to use base coating (P-01A) applied with a rotary machine polisher and apply the coating with a LPHV spray gun as I feel this gives a consistent thickness and coverage.

a)        Using a low pressure spray gun sat at a low pressure setting. Open the fan nozzle all the way and shut the volume all the way down. Fill your cup and press back your trigger while you slowly open up your fluid volume. Liquid should just start coming out and stop there. Now you'll want to set your gun about 5 or 6 inches from some paper or glass. Start spraying again making passes while adjusting your fluid so the paper/glass gets misted, not damp where it runs but more like its damp where a finger can smear it off. If it’s runny you have too much fluid and/or too much pressure (try 12 or 15 PSI) and adjust until you’re happy with the settings.

b)       Use the P-01A primer (I recommend this be used prior to whatever Modesta coating is used) Apply with a mechanical polisher using slow speed or by hand. Apply the coating to a wet applicator and then spread it evenly on the paint surface.  Then buff it wet with a wet towel. Although this might sound strange to some readers, it is a recommended application method of the manufacturer.
Inspect the panel with adequate lighting within 5-10 minutes looking for any thick areas that have not flashed away to clear.

Due to the construction of micro fibre towels, they comprise a hydrophobic Polyester (a scrubbing fibre) which also gives the material strength and durability and a hydrophilic Polyamide (an absorbing fibre) that is tremendously absorbent and quick drying. This nylon hybrid is created during weaving to create microscopic loops, which form a network of tiny hooks, scrubbing away dirt and grime. 

The nature of this yarn is that it is an absorbent; the reason polyester appears to absorb liquids is the many thousands of micro fibres that collectively encapsulate liquids.One of its drawbacks is that it has a propensity to lint, if any lint is present after the coating is cured its removal would entail abrasive polishing and re-application of the coating

1)       Dr Joe dedicated Lint-Free 100% Cotton Surgical Towels, that  have a lint free, tight cotton herringbone weave and a thread count of 170  per square inch,  which is ideal for hard surfaces as they have more ‘grip’ than micro fibre towels and helps to spread the coatings evenly.Fold the towel in half and then half again.

1)       The coating can also be applied with a lint-free and non-abrasive microfiber suede cloths (very low nap), which will evenly spread the coating as opposed to absorbing it. Edgeless optical grade suede weave Use a fresh cloth with an applicator block to help you lay down the perfect application of liquid coatings and other protection products. The Rag Company Detail Master™ Pro but the major disadvantage of this type of application is the coating dries and solidifies to glass, which means the towels will be discarded after use.

Drying / Curing
Use of infra-red lamps is highly recommended, the infrared drying / curing / process will add additional strength, resistance and durability to the coating.  allow 24 hours in a moisture / dust free environment

Infrared heating
Transmit infrared radiation to the coating to enable product to cure, infrared heat will also aid product overall drying, improving both gloss and hardness. When large surface area need to be heated, infrared lamps are often used in banks. Infrared heat lamps are commonly incandescent bulbs which are able to produce infrared radiation. Infrared lamps have many industrial applications including curing coatings

Wavelength ranges
The wavelength of an infrared emitter has a major influence on the efficiency of a thermal process. The better the emitted wavelength fits the absorption spectrum of the material to be heated, the more efficient the process. For instance, water absorbs best at about 3000 nm. Therefore, medium-wave and carbon infrared (CIR) emitters are optimal to heat water and water-based coatings. 

The main emission of these emitters lies exactly within the range of the main absorption of water. Another important emitter parameter is power, measured in W/cm (emitter length) or W/cm2 (heated surface). Due to the higher temperatures of the heating filaments, the power density of short-wave or halogen emitters is in most cases higher than that of medium-wave infrared emitters.

Selection Criteria
Coating drying and curing times vary according to temperature, humidity and air movement. Raising the surface temperature not only drives out the solvent, making the coating dry to the touch, but it promotes the chemical cross link of the coatings components and the paint surface. The faster those two components hook up, the sooner the work can be delivered. Several IR (infrared) vendors suggest that dry times can be reduced by 60 percent over ambient, unassisted dry times when portable heat is carefully applied.

When selecting an infrared emitter for an industrial process, wavelength and power are among the most important parameters that are taken into account. They use low amounts of energy, have an ability to heat quickly, and are low cost.  Infrared emitters differ from illuminating lamps in their low filament temperature, resulting in much less light and more infrared radiation. They are designed for use in applications specifically requiring a short-wave infrared radiation source.  They are commonly supplied with either a clear, red, or inside frosted bulb.  The heat is not determined by the colour or finish of the lamp; however, it is determined by the wattage of the lamp.

Important performance specifications to consider when searching for heat lamps include wavelength range, watts, voltage, life hours, and operating temperature.  The wavelength range is the range of wavelengths the lamp is designed to emit.  Heat lamps are designed to emit light in the Near Infrared (.7µm-1.3µm), Middle Infrared (1.3µm-6µm), Far Infrared (6µm-40µm), and Far-Far Infrared (40µm-1000µm). 

 As has been stated earlier, the achievement of the precise wavelengths of ultraviolet light suitable for curing coatings is very important if a system is to be highly efficient.

By far, the most widely used is the medium pressure mercury arc lamp (an MPMA Lamp). This can be air or water-cooled and can be manufactured in a wide range of lengths. Single lamps of two metres long are not uncommon, and the working life of MPMA lamps can be expected to be well over 1000 hours. They lamps emit not only ultraviolet light, but also visible light, and wavelengths in the infrared spectrum. In fact, all lamps emit approximately 20% ultraviolet light, 60% infrared light and 20% visible light. It is therefore important that when selecting a lamp, output in the ultraviolet spectrum should be closely examined.

·          Watts specifies the power of the lamp.  Heat lamps consume a large amount of wattage but product little light. 
·          Voltage specified refers to the voltage of the electrical input. 
·          Life hours are the average length of the lamp in hours. 
·          Operating temperature is the temperature range the lamp is designed to operate in.

Lamp Life

Medium-pressure mercury arc lamps do not normally fail suddenly, as do ordinary household light bulbs.  Efficiency declines relatively slowly, until insufficient UV light is being emitted for the lamp to cure effectively. This decline is caused primarily by the deterioration in UV transparency of the quartz jacket, and depends on a number of factors- lamp cooling efficiency, power rating, current rating of the electrodes, electrode cooling efficiency, contamination of the lamp's external surface (dust etc.) and switching frequency.

Emissivity of the substrate.

A steel substrate (like a body panel) will only get so hot if the surrounding air is cooler than the panel. So I can point an infrared heat light at the steel panel and leave for lunch. The panel will only get to about 135-140 degrees (if the shop air is cooler than that) and stay there Ñ the point of emissivity. Plastic substrate has an emissivity point of about 180-185 degrees. If I point the heat light at the plastic bumper and head out to lunch, bad things will happen. The plastic may become hard and brittle internally and deform externally. 

Many vendors recommend covering thin plastic parts with reflective foil tape if they can’t be removed.

So how do you control the temperature of the panels?

The most expensive infrared heaters have a remote-temperature sensor that turns the unit on and off to prevent over-heating the panels. Curing time average 2-4 hours. Most heat lights should be placed somewhere between 20 inches and 36 inches away from the panel (exact recommendations are available from your vendor). Too close and the panel will get too hot, possibly causing solvent pop or hard polishing of the topcoat. Too far away and the panel won’t get warm enough, possibly causing uncured spots.

Coating Maintenance
Many people have the incorrect impression that paint coatings are a “no maintenance required” type of product.  This is simply not true.  Routine washing is crucial.  As your coating becomes covered with dirt and contamination, you will notice a decrease in hydrophobic properties. It’s important to remove any surface contaminates on a regular basis with a car wash concentrate that will not leave gloss enhancers or surfactants behind due to a coatings ‘roll off’ washing and drying the paint surface is very easily accomplished

The normal car wash concentrates mostly contain surfactants and alkaline additives. They work by breaking down surface tension and wetting the surface to facilitate soil removal by flushing. With many of the newer coatings traditional car wash solutions, especially at their normal extreme dilutions.
I would recommend the use of a specially formulated product like H-05 Shampoo– specifically formulated for hydrophilic coatings. This special shampoo removes dirt and restores/prolongs the coating’s original hydrophobicity. This is an ideal coating maintenance shampoo

Dry surfaces with a pre-washed waffle weave (pique) towels to ensure zero marring to the paint surface

Polish the paint surface to remove (without removing too much clear coat) any surface imperfections as this product cures to become optically clear and will highlight any surface defects. It has always puzzled me why people over-polish their car paint and cause the paint to fail prematurely; we all have seen examples of clear coat failure. A coating is the most effective way to avoid premature failure of clear coats.


1.        Royal Society of Chemistry (RSC) Library & Information Centre
2.        Glossary of Chemical Terms - Faculty of Chemical Technology
3.        Basic Concepts of Nanotechnology, History of Nano-Technology, News, Materials and Potential Risks
4.        Lotus-inspired nanotechnology applications, B. Karthick1  and Ramesh Maheshwari
5.        SpecialChem4 Polymers
6.        Macromolecular Chemistry and Physics
7.        European Coatings Handbook 2nd Edition, by Brock, Groteklaes, Mischke
8.        Bayer Material Science, Automotive  eNewsletters (Coating, Adhesives and Specialties)

The information in this article is based on the current status of the technical development as well as our experience with the products.

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