PVDF resin-based paint composition
Paint coatings may be described as a thin layer of film containing resin and pigments that is applied to a material’s surface to provide protection and a decorative appearance. The resin system determines the performance and properties of the painted finish, and the pigment provides the color.
For more than 50 years, polyvinylidene fluoride (PVDF) resin systems have demonstrated consistent, reliable performance for aluminum-framed fenestration. The percentage of the resin component defines the coating’s designation. For example, a 70 percent PVDF resin-based paint coating formulation contains 70 to 80 percent by weight PVDF in the coating binder or resin, with the remainder of the binder being a compatible acrylic. Although the acrylics are used in relatively small quantities—typically 20 to 30 percent by weight—they can improve the coatings’ pigment wetting and adhesion properties. This way, the acrylic properties complement the highly inert PVDF.
In liquid paints, the resin accounts for approximately 20 percent, the pigment 10 percent, and liquid solvent used to deliver the paint represents up to 70 percent of the total coating system. A small percentage of reducer and additive components also may be included to adjust viscosity, enhance gloss, or impart other characteristics.
PVDF resin-based architectural coatings for fenestration are specified as either 50 percent PVDF or 70 percent PVDF. Occasionally, a paint resin or coating system manufacturer’s brand name may be mistakenly used as a specification. For example:
- Hylar PVDF resins are a registered brand of Solvay.
- Kynar PVDF resins are registered brands of Arkema Inc.
- Acroflur 50 percent PVDF coating systems and Fluropon 70 percent PVDF coating systems were registered brands of Valspar, and are now owned by The Sherwin-Williams Company.
- Acrynar 50 percent PVDF coating systems and Duranar 70 percent PVDF coating systems are registered brands of PPG.
- Trinar 70 percent PVDF coating systems are a registered brand of AkzoNobel.
As standard, PVDF architectural coatings for fenestration typically are two-coat systems that include a primer and the color coat. Three- or four-coat systems may be used for specialty colors and metallics. Typically, the paint code will have a numerical identifier indicating the number of coats and whether a clear topcoat is needed. Adding a clear coat to a paint finish when it is not required will not add value to the finish and may add unnecessary cost.
Streamlined factory finishing with a focus on environmental responsibility
Extruded aluminum framing is the most commonly specified material for fenestration assemblies on commercial buildings. Aluminum is infinitely recyclable, widely available, and relatively easy to form and fabricate into windows, curtain wall, storefront, and entrances. Aluminum’s light weight makes it economical for shipping, and versatile for installing either as pre-assembled products or as field-assembled systems. However, it should also be noted, extraction and production of primary metals can be energy intensive and has environmental effects.
