Modern times have seen the rise of aluminum as a prime exterior material, largely due to its rugged durability, design versatility, and aesthetic possibilities. However, for all its bravado and beauty, in order to be both functional and pleasing to the eye, aluminum must be coated with a unique finish that allows the metal to resist chalking, pitting, chipping, or premature aging.
Many advances have been made in recent years to aluminum coating technology. In response, the American Architectural Manufacturers Association (AAMA) has raised the bar for peak performance requirements for the long-term durability of organic coatings for aluminum extrusions. The AAMA has documented a new series of performance standards that places stringent performance requirements fir grades of applied organic coatings. The performance standards prior to this change were basically 'good' (AAMA 603) or 'better' (AAMA 605) where 'better' was the high-performance coating grade.
The new voluntary specification performance requirements are now broken into three categories: AAMA 2603, AAMA 2604, and AAMA 2605.
The new specification standards will allow architects, building owners, engineers, and contractors to better select and specify the most appropriate organic coating performance level as each individual project requires.
The new AAMA specifications for paint finishes
AAMA 2603 is primarily intended for interior coatings of at least 20 microns (0.8 mil) thickness. This specification requires test methods and acceptance criteria for color uniformity, gloss, dry film hardness, adhesion, impact resistance, chemical resistance, corrosion resistance, and weathering. This standard submits that a 1-year outdoor exposure test in a South Florida environment that verifies chalking, crazing (small hair-line cracks in the finish), adhesion loss (peeling), chalking and fading is optional.
AAMA 2604 and 2605 specifications are intended for architectural and commercial-grade applications and require a coating of at least 30 micron (1.2 mil) thickness. Both of these standards require the same test methods and performance criteria that tests color uniformity, gloss, impact and chemical resistance. To differentiate between AAMA 2603, these standards require additional testing for abrasion and chemical resistance, and weathering. Weathering tests look at color and gloss retention, chalk resistance, and erosion resistance in a South Florida environment.
AAMA 2604 sets the standards for finishes that do not utilize chromium pretreatment processes. In some areas, this process is disallowed for environmental reasons due to the heavy metal application.
AAMA 2605 sets the standards for complete coating processes that do use chromium pretreatment and high performance coating formulas. Chromating, or the pretreatment process for the chemical conversion process, has a profound influence on the properties of the coating. The substrate metal is part of the coating reaction, becoming a component of the coating. The chemistry involves reaction between the metal surface and an aqueous solution that contains chromates and activator ions. The activators include fluorides, phosphates, and other compounds.
Chromates for aluminum fall into two categories: chrome-phosphates, primarily those used on architectural aluminum extrusions to provide a paint-bonding coat, and chrome oxides applied to almost every type of aluminum. Baths for applying chrome phosphate consist of chromate ions, phosphates and fluorides. Many finishers apply this type of chromate by spraying it on cleaned aluminum extrusions, but some dip lines are in operation. It is common practice to use a passivating hexavalent chromium rinse as the final step in the treatment. A typical cycle would be:
+ Alkali clean.
+ Rinse
+ Chromium-phosphate.
+ Rinse.
+ Hexavalent chromium rinse (seal).
Paint is customarily applied in-line by electrostatic spray and then baked, producing a finished extrusion ready for assembly. This process produces remarkable adhesion. Corrosion resistance is also excellent if the final seal and paint are properly selected.
Warranties
It is extremely important to note that corrosion resistance tests all include varying conditions of humidity and salt spray exposure. Read finishing warranties carefully. Many state a given warranty coverage, with exceptions for coastal exposure such as the following:
"In order for [...] warranty to be effective in environments with a salt atmosphere or relative to bodies of salt water the following criteria must be adhered to:
(1) Application in proximity to a coastline with surf, the distance from the coast must be at a minimum of 2,800 feet."
"This limited warranty [...]is not valid for failures resulting from [...] damage caused by corrosive or aggressive atmospheres such as those contaminated by chemical fumes or salt spray."
"Subject to the conditions set forth below, [...] warrants its coil coated Kynar 500 material to perform as follows in normal atmospheric conditions (which term excludes corrosive aggressive atmospheres such as those contaminated with chemical fumes or salt spray)..."
Normally a reputable certified coating applicator will want to know the location of the aluminum project and will warrant the finish accordingly.
Kynar® high-performance fluoropolymer resin
In addition to the pretreatment process, KINGBIRD INDUSTRIES recommends finishing aluminum products for coastal environments with a PVDF finish. Polyvinylidene Fluoride, or PVDF is a highly non-reactive and pure thermoplastic fluoropolymer.
PVDF is a specialty plastic material in the fluoropolymer family and is used in applications that require the highest strength, and resistance to solvents or acids. KYNAR® 500 PVDF or HYLAR® 5000 PVDF is used as the principal ingredient of high-end paints for aluminum. These PVDF paints have extremely good gloss and color retention, and they are in use on many prominent buildings around the world.
Noted by architects around the world Kynar 500® PVDF resin-based coatings is precisely the product necessary to provide protection and preservation to aluminum architectural products. No other coating system withstands the rigors of time and nature like those based on Kynar 500® resins. This high-performance fluoropolymer resin, with its extraordinary capability to retain color and gloss, keeps painted metal looking vibrant and appealing.
Kynar 500 resin-based finishes are available worldwide through a strict licensing program. This licensed distribution ensures the quality, consistency and high performance of Kynar 500® resin-based coatings.
Protecting the Finish
Today's high-quality architectural finishes are extremely durable, but even the best finish needs care and protecting, just like your car!
All finished aluminum products, and particularly those located along the coast, require a routine cleaning and maintenance program so that the finish retains its original beauty. When selecting a cleaning solution, use mild soap solutions taht are safe enough for use with your bare hands, or products similar to what you would use to wash your car. Avoid the use of strong acid or alkali cleaners, such as window cleaners, that may damage the finish.
Solvents no stronger than mineral spirits or denatured alcohol may be used to remove grease, sealants, or other materials. Never mix cleaners or cleaners and solvents as the mixture can often cause harmful or extremely dangerous results. Do not use abrasive cleaners or materials such as steel wool or abrasive brushes, which will also harm the finish.
Once heavy soil and grease is removed, the mild soap solution should be applied with a soft cloth, sponge or soft brush. Rinse the surface thoroughly with clean water and dry with a soft cloth.
In coastal areas where the finish is exposed to salt spray or in areas containing heavy industrial pollutants, clean your aluminum architectural feature at a minimum of every 3-month intervals. In other areas, cleaning should be scheduled every 6-months. Note that a routine cleaning and maintenance schedule may be required under the warranty.
KINGBIRD INDUSTRIES provides (3) standard aluminum finishes: anodic (strong but not recommended for close-up viewing - ask us why), powder coating (our most popular finish for standard applications), and KYNAR® 500 PVDF for premium finish durability. At our facility in Salisbury North Carolina, we perform our own powder coating process. For AAMA 2605 and Kynar finishes, we out-source the finishing to a premium licensed finishing company.
KINGBIRD INDUSTRIES offers powder coat standard colors including white, gloss black, gray, dark green, and bronze. Color samples can be sent upon request. Custom colors are available at an additional cost. For restoration projects, we will match any custom color to other colors on your building by collecting a sample and having it custom color-matched at our finishing partner's facilities. Custom color-matching can be quoted on request per your project requirements. Samples are available for any project. Please allow 3-weeks lead time for a Kynar finished sample.
For more information about custom aluminum architectural products, AAMA standards, paint finishes and warranties, contact KINGBIRD INDUSTRIES at 800.882.7092 or email us at sales @schaeferinterstate.com.
Many advances have been made in recent years to aluminum coating technology. In response, the American Architectural Manufacturers Association (AAMA) has raised the bar for peak performance requirements for the long-term durability of organic coatings for aluminum extrusions. The AAMA has documented a new series of performance standards that places stringent performance requirements fir grades of applied organic coatings. The performance standards prior to this change were basically 'good' (AAMA 603) or 'better' (AAMA 605) where 'better' was the high-performance coating grade.
The new voluntary specification performance requirements are now broken into three categories: AAMA 2603, AAMA 2604, and AAMA 2605.
The new specification standards will allow architects, building owners, engineers, and contractors to better select and specify the most appropriate organic coating performance level as each individual project requires.
The new AAMA specifications for paint finishes
AAMA 2603 is primarily intended for interior coatings of at least 20 microns (0.8 mil) thickness. This specification requires test methods and acceptance criteria for color uniformity, gloss, dry film hardness, adhesion, impact resistance, chemical resistance, corrosion resistance, and weathering. This standard submits that a 1-year outdoor exposure test in a South Florida environment that verifies chalking, crazing (small hair-line cracks in the finish), adhesion loss (peeling), chalking and fading is optional.
AAMA 2604 and 2605 specifications are intended for architectural and commercial-grade applications and require a coating of at least 30 micron (1.2 mil) thickness. Both of these standards require the same test methods and performance criteria that tests color uniformity, gloss, impact and chemical resistance. To differentiate between AAMA 2603, these standards require additional testing for abrasion and chemical resistance, and weathering. Weathering tests look at color and gloss retention, chalk resistance, and erosion resistance in a South Florida environment.
AAMA 2604 sets the standards for finishes that do not utilize chromium pretreatment processes. In some areas, this process is disallowed for environmental reasons due to the heavy metal application.
AAMA 2605 sets the standards for complete coating processes that do use chromium pretreatment and high performance coating formulas. Chromating, or the pretreatment process for the chemical conversion process, has a profound influence on the properties of the coating. The substrate metal is part of the coating reaction, becoming a component of the coating. The chemistry involves reaction between the metal surface and an aqueous solution that contains chromates and activator ions. The activators include fluorides, phosphates, and other compounds.
Chromates for aluminum fall into two categories: chrome-phosphates, primarily those used on architectural aluminum extrusions to provide a paint-bonding coat, and chrome oxides applied to almost every type of aluminum. Baths for applying chrome phosphate consist of chromate ions, phosphates and fluorides. Many finishers apply this type of chromate by spraying it on cleaned aluminum extrusions, but some dip lines are in operation. It is common practice to use a passivating hexavalent chromium rinse as the final step in the treatment. A typical cycle would be:
+ Alkali clean.
+ Rinse
+ Chromium-phosphate.
+ Rinse.
+ Hexavalent chromium rinse (seal).
Paint is customarily applied in-line by electrostatic spray and then baked, producing a finished extrusion ready for assembly. This process produces remarkable adhesion. Corrosion resistance is also excellent if the final seal and paint are properly selected.
Warranties
It is extremely important to note that corrosion resistance tests all include varying conditions of humidity and salt spray exposure. Read finishing warranties carefully. Many state a given warranty coverage, with exceptions for coastal exposure such as the following:
"In order for [...] warranty to be effective in environments with a salt atmosphere or relative to bodies of salt water the following criteria must be adhered to:
(1) Application in proximity to a coastline with surf, the distance from the coast must be at a minimum of 2,800 feet."
"This limited warranty [...]is not valid for failures resulting from [...] damage caused by corrosive or aggressive atmospheres such as those contaminated by chemical fumes or salt spray."
"Subject to the conditions set forth below, [...] warrants its coil coated Kynar 500 material to perform as follows in normal atmospheric conditions (which term excludes corrosive aggressive atmospheres such as those contaminated with chemical fumes or salt spray)..."
Normally a reputable certified coating applicator will want to know the location of the aluminum project and will warrant the finish accordingly.
Kynar® high-performance fluoropolymer resin
In addition to the pretreatment process, KINGBIRD INDUSTRIES recommends finishing aluminum products for coastal environments with a PVDF finish. Polyvinylidene Fluoride, or PVDF is a highly non-reactive and pure thermoplastic fluoropolymer.
PVDF is a specialty plastic material in the fluoropolymer family and is used in applications that require the highest strength, and resistance to solvents or acids. KYNAR® 500 PVDF or HYLAR® 5000 PVDF is used as the principal ingredient of high-end paints for aluminum. These PVDF paints have extremely good gloss and color retention, and they are in use on many prominent buildings around the world.
Noted by architects around the world Kynar 500® PVDF resin-based coatings is precisely the product necessary to provide protection and preservation to aluminum architectural products. No other coating system withstands the rigors of time and nature like those based on Kynar 500® resins. This high-performance fluoropolymer resin, with its extraordinary capability to retain color and gloss, keeps painted metal looking vibrant and appealing.
Kynar 500 resin-based finishes are available worldwide through a strict licensing program. This licensed distribution ensures the quality, consistency and high performance of Kynar 500® resin-based coatings.
Protecting the Finish
Today's high-quality architectural finishes are extremely durable, but even the best finish needs care and protecting, just like your car!
All finished aluminum products, and particularly those located along the coast, require a routine cleaning and maintenance program so that the finish retains its original beauty. When selecting a cleaning solution, use mild soap solutions taht are safe enough for use with your bare hands, or products similar to what you would use to wash your car. Avoid the use of strong acid or alkali cleaners, such as window cleaners, that may damage the finish.
Solvents no stronger than mineral spirits or denatured alcohol may be used to remove grease, sealants, or other materials. Never mix cleaners or cleaners and solvents as the mixture can often cause harmful or extremely dangerous results. Do not use abrasive cleaners or materials such as steel wool or abrasive brushes, which will also harm the finish.Once heavy soil and grease is removed, the mild soap solution should be applied with a soft cloth, sponge or soft brush. Rinse the surface thoroughly with clean water and dry with a soft cloth.
In coastal areas where the finish is exposed to salt spray or in areas containing heavy industrial pollutants, clean your aluminum architectural feature at a minimum of every 3-month intervals. In other areas, cleaning should be scheduled every 6-months. Note that a routine cleaning and maintenance schedule may be required under the warranty.
KINGBIRD INDUSTRIES provides (3) standard aluminum finishes: anodic (strong but not recommended for close-up viewing - ask us why), powder coating (our most popular finish for standard applications), and KYNAR® 500 PVDF for premium finish durability. At our facility in Salisbury North Carolina, we perform our own powder coating process. For AAMA 2605 and Kynar finishes, we out-source the finishing to a premium licensed finishing company.
KINGBIRD INDUSTRIES offers powder coat standard colors including white, gloss black, gray, dark green, and bronze. Color samples can be sent upon request. Custom colors are available at an additional cost. For restoration projects, we will match any custom color to other colors on your building by collecting a sample and having it custom color-matched at our finishing partner's facilities. Custom color-matching can be quoted on request per your project requirements. Samples are available for any project. Please allow 3-weeks lead time for a Kynar finished sample.
For more information about custom aluminum architectural products, AAMA standards, paint finishes and warranties, contact KINGBIRD INDUSTRIES at 800.882.7092 or email us at sales @schaeferinterstate.com.
