How to affect the performance of powder coatings under oven conditions

As the world pays more and more attention to environmental protection, "paint powder" has become a trend in the coatings industry. Ovens are a popular choice among household appliances. For electrostatic coating of metal surface materials, baking varnish is used instead of baking varnish.

 

How to affect the performance of powder coatings under oven conditions

Powder coating performance

Most powder finishes are actually thermoset, which indicates that an irreversible chemical reaction occurs during processing in the oven. The degree of treatment has a major impact on the final performance of the surface. The degree of particle elimination will affect the appearance and toughness of the coating.

 

Gloss

Low gloss and matte finishes are actually usually produced by the remedial reaction of various ingredients in the treatment formulation. This is actually a typical method used by formulators to develop a truly relaxed but less polished appearance. Therefore, inadequate treatment can result in gain changes. This is actually very popular in mixed powders and epoxy powders, but it is also easy to notice in some polyester and polyurethane solutions. Therefore, it is important to control oven issues when curing matt and low gloss powders. If the varnish of the part is higher than the assumed value, it may be due to insufficient treatment of the powder coating. In most cases, you can easily rebake the components, and the gloss will lose the defined classification.

 

Coating durability

Priming powder coatings will not only destroy the mechanical properties, but also the ultimate durability of the paint. Incomplete crosslinking will result in reduced corrosion resistance, chemical and solvent resistance, and poor outdoor durability. Therefore, it is important to ensure a complete cure.

 

One of the most common tests involves evaluating the solvent resistance of the coating (test instrument: solvent resistant wiper). ASTM D5402 describes this test. Basically, you can wipe the surface 25 to 50 times with a cloth or cotton swab soaked in acetone (or methyl ethyl ketone). Your powder coating supplier will be happy to recommend the number of rubs for the coating. In some cases, it is recommended to use a less corrosive solvent mixture (eg 90% xylene/10% MEK) for this test. According to the chemical nature of the coating, the fully cured powder will pass the solvent friction test and soften slightly, but will not dissolve and transfer to the rag or cotton swab in the workshop.

 

The influence of oven conditions on powder chemistry

The coating formulation has an important influence on the behavior of the product in the oven.

 

Volatile

The volatile content of thermosetting powder coatings depends on the formulation and chemical properties. During the baking process, all powder coatings will release approximately 0.5% to 1.0% of water. Another small part of organic volatiles is also discharged from the coating.

 

Color stability

Epoxy resins tend to exhibit minimal color and excessive baking stability. It is especially noticeable for white and light colors. Mixed materials are better. Polyurethane and TGIC polyester have excellent color stability in a certain temperature range. The color stability of low-temperature curing powders is lower than that of standard baked powders because they contain catalysts to promote accelerated curing. HAA polyester is more prone to yellowing than TGIC polyester.

 

Generally speaking, not all powder coatings are the same, and each powder coating responds to oven conditions in its own unique way. Oven settings (including part density and load) are critical to obtain adequate curing and acceptable coating performance. Therefore, it is necessary to understand your powder coating products and to set and monitor oven parameters to ensure consistent quality and coating performance.

We are customized oven powder coating OEM, manufacturer, exporter, factory,

The above sharing hopes to be helpful to you.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Product Detail
Type	Epoxy and Polyester Powder Coating
Color	RAL and PANTONE or customized
Surface Finish	smooth/sandy/wrinkle/metallic/chrome/wood/hammer /glitter and customized
Glossy Level	High glossy/semi glossy/matt
Coverage	5~6 square meters per kg at 40~90μm film thickness
Film Thickness	50~90μm
Specific Gravity	1.2~1.9 per CBM
Application	Construction aluminium profile, advertisement board, outdoor lamps, highway guardrail, road fence, outdoor metal furnitures, lamp pile, crust of air conditioner, agricultural equipment or can be used on the surface coatingof other metal work that require good performance in the environment of high-intensity ultraviolet ray.

 

   

Foshan Wolong Chemical Plant Co., Ltd. is a large-scale specialized powder coatings
manufacturer in China. Our company covers more than 20,000 square meters of area .