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Drawbacks with liquid coating and overlays on MDF finishing
The two most widely used finishing techniques for MDF boards are: Liquid coatings Paper-based laminates (mostly melamine impregnated) and Thermoplastic foils (PVC, ABS, polyolefine-based) A range of surface appearances and qualities can be obtained with these technologies. However, there can be some drawbacks with both liquid coating systems and overlays, which can be overcome by use of UV powder coating. When using liquid coatings, normally a multi-coat system with interlayer sanding is required to achieve attractive finishes. This means thatRead More …
Binder and Crosslinkers for UV Powder Coatings
The most suitable approach for a coating formulation is the use of a major binder and a crosslinker. The cross¬linker may control the network density for the coating, while the binder determines properties of the coating such as discoloration, outdoor stability, mechanical properties, etc. Furthermore, this approach will lead to a more homogenous concept in the powder coating applications as a category bringing similitude to thermosetting coatings where crosslinkers such as TGIC and hydroxyl amides are used. A crosslinker shouldRead More …
New benefits due to the combined technology of UV and powder coating
The latest development in powder coatings is the combination of powder coating technology and UV technology. This approach shows some very important benefits. The benefits due to powder coating technology versus liquid coatings are: Elimination or reduction of intermediate sanding steps; High performance at high utilization rate, reclaim leading to 95% powder usage; No VOC during the curing process; and Easy recycling and no waste treatment. New benefits due to the combined technology of UV and powder coating are: SplitRead More …
Expanding Application area for UV powder coatings
Blends of specific polyesters and epoxy resins have permitted the development of smooth, high-performance finishes for wood, metal, plastic and toner applications. Wood Smooth, matte clear coats have been successfully applied on hardwood and on veneered composite board, such as beech, ash and oak. The presence of the epoxy partner in the binder has boosted the chemical resistance of all the coatings tested. An attractive market segment for the advanced UV powder coating is as a replacement for polyvinyl chlorideRead More …
UV powder coating for smooth finishes and wooden furniture
UV Powder coating for Smooth, Matt Finishes Blends of specific polyesters and epoxy resins permitted the development of smooth, matt finishes for metal and MDF applications. Smooth, matt clear coats were successfully applied on hardwood, on veneered composite board such as beech, ash, oak and on PVC used for resilient flooring. The presence of the epoxy partner in the binder boosted the chemical resistance of all the coatings. The best smoothness was achieved with the binder of modification without having criticalRead More …
Polyester/Epoxy Combined Chemistry for UV Powder coating
The combination of methacrylated polyester and acrylated epoxy resin offers an interesting blend of properties to the cured film. The presence of a polyester backbone results in good resistance of the coatings in weathering tests. The epoxy backbone gives outstanding chemical resistance, improved adhesion and smoothness. An attractive market segment for these UV powder coating is as replacement for PVC laminates on MDF panels for the furniture industry. The polyester/epoxy blend is achieved in four major steps. The polycondensation in theRead More …
Optimal Performance of UV Powder Coatings
Powder coating cured by ultraviolet light (UV powder coating) is a technology that combines the advantages of thermosetting powder coating with those of liquid ultraviolet-cure coating technology. The difference from standard powder coating is that melting and curing are separated into two distinct processes: upon exposure to heat, UV-curable powder coating particles melt and flow into a homogeneous film that is crosslinked only when it is exposed to UV light. The most popular crosslinking mechanism used for this technology isRead More …
Catalysts are used to improve abrasion resistance of coatings
General strategies of increasing crosslink density by use of higher-functionality oligomers and/or larger amounts of crosslinking agents have been used to improve abrasion resistance. To get the higher crosslink density, catalysts are sometimes added to the paint formulation as additives in small quantities. Catalysts are additives that will increase the rate of a -chemical reaction but are not consumed or changed in the reaction process. Catalysts have widely varying compositions that depend on the nature of the reaction being catalyzed.Read More …
Waxes have also been used to improve slip and thereby abrasion
Waxes have also been used to improve slip and thereby abrasion. Hard waxes resist abrasion better than soft materials. Hard waxes like PE and PTFE waxes function by the ball bearing mechanism, while the softer microcrystalline waxes work via the layer (bloom) mechanism. Microcrystalline wax is a petroleum-based wax that has very different physical properties than paraffin wax. The Blooming Mechanism:Molten wax particles float (or bloom) to the surface. The coating cools down, and re-crystallization of wax particles takes place,Read More …
Acrylic/Melamine Clearcoats solve the problems of mar and scratch demage
When environmental fallout became an issue, clear topcoat technologies were developed to successfully solve the problem. Currently, mar and scratch damage as observed in the field is a problem receiving considerable attention. Car washes can be very abrasive. This wet abrasion action results in an undesirable visual dulling and a striped effect on nearly all current clearcoat technologies. PPG uses nanoscratch testing instrumentation as a means to determine the energetics required to cause the various types of damage to clearcoats. InRead More …