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Performance or Specialty Coating


Cathodic protection
Cathodic protection (CP) is a technique to control the corrosion of a metal surface by making it work as a cathode of an electrochemical cell. This is achieved by placing in contact with the metal to be protected another more easily corroded metal to act as the anode of the electrochemical cell. Cathodic protection systems are most commonly used to protect steel, water or fuel pipelines and storage tanks, steel pier piles, ships, offshore oil platforms and onshore oil well casings.

Cathodic protection can be, in some cases, an effective method of preventing stress corrosion cracking.

Ceramic Coating
Ceramic Coating, is recommend for use on parts that are exposed to extremely high temperatures such as headers or exhaust pipes, often referred to as exhaust coating, header coating or high heat coating. Ceramic coatings increase part longevity, reduces friction, produces more usable power and protects parts from thermal fatigue. The coating is applied to both the inside and outside of the part. It provides a hard finish which is resistant to rust and chipping.

Ceramic coating can be applied over chrome, aluminum, carbon steel, stainless steel or cast iron. Exhaust Coating options include:

Fluoropolymer Coatings
Fluoropolymer coatings are blends of high performance resins and fluoropolymer lubricants. These single coat thin films provide excellent corrosion and chemical resistance. Other benefits of fluoropolymer coatings include reduced friction, resistance to galling, non stick, non wetting, electrical resistance and abrasion resistance. Fluoropolymer coatings are applied to fasteners and various OEM components to provide a longer life before replacement.

Fusion bonded epoxy coating FBE

Fusion bonded epoxy coating, also known as fusion-bond epoxy powder coating and commonly referred to as FBE coating, is an epoxy based powder coating that is widely used to protect steel pipe used in pipeline construction, concrete reinforcing bars (rebar) and on a wide variety of piping connections, valves etc. from corrosion. FBE coatings are thermoset polymer coatings. They come under the category of 'protective coatings' in paints and coating nomenclature. The name 'fusion-bond epoxy' is due to resin cross-linking and the application method, which is different from a conventional paint. The resin and hardener components in the dry powder FBE stock remain unreacted at normal storage conditions.

Floor Coatings
Floor coatings are high build solventless epoxy or polyurethane floor coating systems designed to suit corrosive atmospheres, chemical fumes, and continuous spillage of acids and alkalis, salts etc. Its high abrasion and impact resistance makes it an ideal choice for industrial floors with heavy traffic of trolleys, forklifts.

Galvanizing

In current use, it typically means hot-dip galvanizing, a metallurgical process that is used to coat steel or iron with zinc. This is done to prevent galvanic corrosion (specifically rusting) of the ferrous item; while it is accomplished by non-electrochemical means, it serves an electrochemical purpose.

Hot-dip galvanized steel has been effectively used for more than 150 years. The value of hot-dip galvanizing stems from the relative corrosion resistance of zinc, which, under most service conditions, is considerably better than iron and steel. In addition to forming a physical barrier against corrosion, zinc, applied as a hot-dip galvanized coating, cathodically protects exposed steel. Furthermore, galvanizing for protection of iron and steel is favored because of its low cost, the ease of application, and the extended maintenance-free service that it provides.

Note that exposed steel is painted (much in the same way as exposed aluminium flashings) to colour match the proposed scheme colour

Moisture-cured polyurethane
Moisture-cured polyurethane is one-part polyurethane that its cure is initiatedly environmental moisture. The moisture-curable polyurethane is mainly consists of isocyanate-terminated pre-polymer. Various types of pre-polymer can be used to provide required property. For instance, isocyanate-terminated polyether polyols are used to provide good flexibility due to their low glass transition temperature. Combining soft segment, such as polyether, and hard segment, such as polyurea, provides good hardness and flexibility of coatings. Moreover, the properties are also controlled by selecting types of isocyanates to incorporate with pre-polymer. Two main types of isocyanates are aromatic isocyanate and aliphatic isocyanate. Aromatic isocyanate has high reactivity. However, it has poor exterior durability and severe discoloration. Some examples of aromatic isocyanates are toluene diisocyanate(TDI) and 4,4diphenylmethane diisocyanate(MDI). On the other hand, aliphatic isocyanate, such as, isophorone diisocyanate (IPDI), offers excellent weatherability and color retention; nevertheless, the reactivity of aliphatic isocyanate is low, so some catalysts may be required. Therefore, types of isocyanate are important to achieve desirable property. Furthermore, additives, solvents, pigments, etc. can be added based on application. However, raw materials for moisture-cured PU must be controlled to be moisture-free in order to obtain good storage stability and film property.

The other advantage of moisture-curable polyurethane is that it is one component. Therefore, it is easy to use since no proper mixing ratio is required, compared to two-component coatings. The moisture-cured PU is crosslinked by the reaction of Isocyanate-terminated pre-polymer and water in the air, producing amines and small amount of carbon dioxide. Finally, the reaction of amines and the rest of isocyanate-terminated pre-polymer takes place which, forms urea linkage.

Molybdenum Disulfide Coating
Molybdenum Disulfide Coatings are commonly used in applications where load carrying capacity, operating temperature and coefficient of friction are primary concerns. This coating provides effective lubrication in a wide range of loads, in many cases exceeding 250,000 psi. Moly coatings lubricate sacrificially by transferring lubricant between the two mating surfaces, which helps to reduce the wear and the coefficient of friction.

Moly coatings are a combination of molybdenum disulfide lubricant and high performance resins. Moly coatings are thermally cured and thoroughly bonded to the base metal of the coated part.

Phenolic Coatings
Phenolic coatings offer consistent high quality protection for a wide range of applications including immersion service for most acids, solvents, and salts. This coating is typically used where low pH environments and higher temperatures are factors. Phenolic coatings have excellent resistance to 92% - 98% sulfuric acid at temperatures up to 120F. Phenolic coatings are also resistant to hydrochloric acid, phenol, anhydrous chlorobenzene, carbon tetrachloride, and many other chemicals.

Parylene
Parylene is the tradename for a variety of polyxylylene polymers marketed by several providers,

Polytetrafluoro Ethylene (PTFE) Coatings
PTFE (polytetrafluoro ethylene) nonstick coatings are two-coat (primer/topcoat) systems. These products have the highest operating temperature of any fluoropolymer, extremely low coefficient of friction, good abrasion resistance, and good chemical resistance.

PTFE coatings can withstand a maximum use temperature of 600F. This coating is typically applied to a thickness of 1-3 mils.

Polyurea coating
Polyurea coating is basically a two-component system based on Amine terminated prepolymer crosslinked with Isocyanate which forms the urea linkages. The crosslinking between reactive polymers take place at a rapid speed at ambient temperature. Normally this reaction does not require any catalyst. Since the Pot-life of such coating is within seconds; special type of Plural Component spray gun is require to carry out the application. The coatings can build up to 500 to 1000 microns of thickness in a single appllication. Because of such high thickness it gives excellent chemical and abrasion resistance. However, the desired property largely depends on the surface preparation of the object to be coated. It is recommended to sand blast or grit blast the surface as per standard method [e.g., Sa 2, SSPC-SP10/NACE No.2] to near white metal. Despite of such a high thickness it still imparts excellent flexibility; elongation [around 300%] and low permeability. Typical application includes on concrete mainly in water tunnel where high water is passed with high velocity and pressure, tank lining, industrial flooring and various metal structure.

Polyvinyl fluoride Coating
Polyvinyl fluoride (PVF) or -(CH2CHF)n- is mainly used in flammability-lowering coating of airplane interiors and photovoltaic module backsheets. It is also used in things like raincoats, and metal sheeting. Polyvinyl fluoride is a thermoplastic fluoropolymer with the repeating vinyl fluoride unit: It is structurally very similar to polyvinyl chloride.

PVF is also used as whiteboard surface material and has recently been used as part of the Phoenix Mars Lander's biobarrier.

Polyurethane Coatings
Polyurethane coatings provide a thin film, high gloss finish with exceptional weathering performance characteristics. This coating is used in virtually all industrial markets to provide a smooth durable finish that has superior resistance to corrosion, abrasion, and chemical exposure. Polyurethanes are normally used to topcoat high build epoxy and inorganic zinc.

PVDF Coating
Polyvinylidene Fluoride, or PVDF is a highly non-reactive and pure thermoplastic fluoropolymer. It is also known as KYNAR, HYLAR or SYGEF.A fine powder grade, KYNAR 500 PVDF or HYLAR 5000 PVDF, is also used as the principal ingredient of high-end paints for metals. These PVDF paints have extremely good gloss and color retention, and they are in use on many prominent buildings around the world, e.g. the Petronas Towers in Malaysia and Taipei 101 in Taiwan, as well as on commercial and residential metal roofing. This coating is unaffected by most chemicals and solvents and has excellent wear and abrasion resistance. PVDF also has a high dielectric strength, excellent resistance to weathering and the ability to self extinguish.

Polytetrafluoroethylene PTFE Teflon
In chemistry, poly(tetrafluoroethylene) or poly(tetrafluoroethene) (PTFE) is a synthetic fluoropolymer which finds numerous applications. PTFE is most well known by the DuPont brand name Teflon.

PTFE is a fluorocarbon solid, as it is a high molecular weight compound consisting wholly of carbon and fluorine.

Anti Bacterial/ Anti Fungal Coating /
In hygiene sensitive environments, it is vitally important to protect against the growth of micro-organisms on internal walls and ceilings.  Anti Bacterial / Anti Fungal Coating  contain an active film protectant which kills bacteria on contact and prevents the growth of mould (fungi) and yeast. E.g. E coli, Staphylococcus Aureus, Aspergillums Niger and many many others
.
Glass Coating

Anti-reflective coating
Anti-reflective or antireflection (AR) coatings are a type of optical coating applied to the surface of lenses and other optical devices to reduce reflection. This improves the efficiency of the system since less light is lost. In complex systems such as a telescope, the reduction in reflections also improves the contrast of the image by elimination of stray light. This is especially important in planetary astronomy. In other applications, the primary benefit is the elimination of the reflection itself, such as a coating on eyeglass lenses that makes the eyes of the wearer more visible, or a coating to reduce the glint from a covert viewer's binoculars or telescopic sight.

Many coatings consist of transparent thin film structures with alternating layers of contrasting refractive index. Layer thicknesses are chosen to produce destructive interference in the beams reflected from the interfaces, and constructive interference in the corresponding transmitted beams. This makes the structure's performance change with wavelength and incident angle, so that color effects often appear at oblique angles. A wavelength range must be specified when designing or ordering such coatings, but good performance can often be achieved for a relatively wide range of frequencies: usually a choice of IR, visible, or UV is offered.

Roof coating
A roof coating is a monolithic, fully adhered, fluid applied roofing membrane. It has elastic properties that allows it to stretch and return to their original shape without damage.

Typical roof coating dry film thickness vary from paint film thickness (plus or minus 3 dry mils) to more than 40 dry mils. This means a roof coating actually becomes the top layer of a composite roof membrane and underlying system. As such, the roof coating is the topmost layer of protection for the membrane, receiving the impact of sunlight (both infrared and ultraviolet (UV), rain, hail and physical damage.

A roof coating can be applied by brush, roller or spray. An airless sprayer is recommended for best results.


Vacuum deposition
Vacuum deposition or vacuum coating is a family of processes used to deposit layers atom-by-atom or molecule-by-molecule at sub-atmospheric pressure (vacuum) on a solid surface. The layers may be as thin as one atom to millimeters thick (freestanding structures). There may be multiple layers of different materials (e.g. optical coatings). A thickness of less than one micrometre is generally called a thin film while a thickness greater than one micrometre is called a coating. The vacuum environment may serve one or more purposes including:

reducing the particle density so that the mean free path for collision is long
reducing the particle density of undesirable atoms and molecules (contaminants)
providing a low pressure plasma environment
providing a means for controlling gas and vapor composition
providing a means for mass flow control into the processing chamber.

Condensing particles may come from a variety of sources including:

Thermal evaporation, Evaporation (deposition)
Sputtering
Cathodic arc vaporization
Laser ablation
Decomposition of a chemical vapor precursor, chemical vapor deposition
When the vapor source is from a liquid or solid material the process is called physical vapor deposition (PVD). When the source is from a chemical vapor precursor the process is called low pressure chemical vapor deposition (LPCVD) or, if in a plasma, plasma enhanced CVD (PECVD) or "plasma assisted CVD" (PACVD). Often a combination of PVD and CVD processes are used in the same or connected processing chambers.

Vacuum metallizing
In vacuum metallizing a metallic coating material placed in a vacuum chamber with the workpiece to be coated. The material that is being applied is then heated until it starts to evaporate, this vaporized metal condenses on the product or workpiece as a thin metallic film. As this is happening the part is being rotated for uniformity of the coat

Process characteristics
Done within a vacuum
Vaporizes the metal
Can be used on glass, plastic, metal, ceramic, and paper materials
Pieces being coated must be extremely clean
It produces a very thin coat of metal
 




 
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