At Shamrock, we work closely with our powder coatings customers to minimize the impact of abrasion and mar on finished products. We also offer unique texturing agents that develop tactile surfaces ranging from coarse to smooth finishes and are suitable for use in a wide variety of baking conditions. Shamrock additives are ideal for a broad spectrum of powder coatings applications, including general industrial, appliance, metal furniture, electronics, farm equipment and automotive OEM and aftermarket parts.
The Power of Wax in Powder Coatings
Wax additives are used to improve mar and abrasion resistance in coatings. Polytetrafluoroethylene (PTFE) is a very cost-effective texturing additive for powder coatings. It offers performance advantages in powder coatings, such as ease of incorporation, excellent recoat adhesion and cake-free powder transfer. Our products offer the following benefits:
- Reproducible and uniform texture
- Low coefficient of friction (COF)
- Outstanding mar and abrasion resistance
- Cost effectiveness
- Suitable for high bake temperatures
- Prevents agglomeration of finished power
- Acts as latent solvent.
- Improves flow of cured film.
- Keeps the film open reducing gassing
- Improves slip and mar resistance
- Useful tool for controlling gloss
- Helps transferring of powder from hopper
What is Outgassing?
Outgassing occurs when gases are releases through a powder coating during the curing process; leaving behind pin holes. Moisture or corrosive material could penetrate through the pinholes corroding the part.
Waxes allow the coating to remain soft and “open” during the melt and cure cycle. This open phase allows the volatiles to emerge through the coating. Once this occurs the coating; the wax reflows filling the voids left by the emerging gases. Products such as S-379H, S-363, S-400 SP5 and SPP-40 are recommended for this application.
Abrasion results from scuffing, scratching, wearing down, marring, or rubbing away. Products such as S-395 SP5, Taber Tiger 5512, S-363, SST-3 and FluoroSLIP® 511 are recommended to provide abrasion resistance.
Micronized PTFE powders improve the static, but not the dynamic coefficient of friction. PTFE is generally used in combination with other waxes such as carnauba or polyethylene. Products such as LoAngle 5413, SST3, Fluoro P-77, S-394/ S-395 are highly recommended to provide slip control.
We recommend using a combination of wax and PTFE to improve scratch, abrasion and mar resistance. Products such as FluoroSlip® 511 is a PE/PTFE for improved Metal Marking and S-394 / S-395 which are made with Medium and High MW PE Wax for improved slip with minimal haze formation.
Texturing Agents provide consistent and uniform texture. PowderTex fibrillates during extrusion process, has very high oil absorption. The PTFE adsorbs the resinduring the curing process and does not interfere with the extrusion to provides reproducible and controlled texture and matting effect.
- PowderTex 61 – Specially processed PTFE with low melt flow index. For satin gloss (15-25°) and controlled texture.
- PowderTex 94 – 100% PTFE, Same as PowderTex 61 but a silky tactile feel
Undesired adhesion may occur under temperature / pressure / long storage leading to visible damage to print integrity when the substrates are separated. To prevent this, we recommend products such as Fluoro P77, S-395SP5, S-483, S-400 SP5 and Taber Tiger 5512
A key benefit of these additives is that they are easy to use. They are micronized to small particle sizes. For the best results, we suggest that all of these additives be incorporated in the pre-extrusion blend. Recommended additive level is 0.5% to 3% by weight depending on the performance requirements