1、 What is powder coating?

Powder coating is a new type of solvent-free 100% solid powder coating. It has the characteristics of solvent-free, pollution-free, recyclable, energy-saving, reducing labor intensity, and high mechanical strength of coating film. Powder coatings include thermoplastic powder coatings and thermosetting powder coatings. If the appearance of the film-forming substance is used, powder coatings can be divided into extinction type, high gloss type, artistic type, etc.

2、 What are the advantages of powder coatings compared to traditional coatings?

1. Powder coating has no pollution to the environment

Powder coatings do not use volatile solvents such as organic solvents and water, so they are inorganic solvent based coatings. It can be said that when using powder coatings, the solvent pollution index is zero. Powder coating can be fully automatic sprayed and is a 100% solid powder coating. Overloaded powder coatings can be fully recycled through a recycling system. Therefore, powder coating can minimize the degree of environmental pollution.

2. Powder coating saves resources and production costs

Traditional liquid coatings contain organic volatile compounds, which can cause harmful substances to evaporate into the atmosphere. Using powder coating can avoid such waste. In addition, the baking time for powder coating is shorter than that for liquid coating, shortening the coating operation line, improving production capacity, and promoting the efficiency of overall coating production.

3. Powder coating has high economic benefits

Due to the use of electrostatic principles for powder coating, the coating equipment can achieve full automation without wasting labor costs. Even if manual assistance is required, coating personnel do not need to undergo long-term training to spray good coatings.

3、 Introduction to Powder Coating Production Technology

The production technology of powder coatings is completely different from that of general liquid coatings. The production of powder coatings involves connecting different work sections in a reasonable order (including preparation time for pre mixing steps, preparation time for main equipment, and quality control time).

The production process of powder coating manufacturers with smaller production scales can be discontinuous; For powder coating manufacturers with high production capacity, it is usually necessary to combine individual processes into a continuous production process.

1. Pre mixing of powder coating production technology

Pre mixing the various components of powder coating before hot melt mixing is an important process that cannot be ignored and plays a decisive role in the performance of powder coating. Especially for those additives and coloring pigments with low usage, if the pre mixing is not sufficient, they cannot be compensated in the second stage of hot melt extrusion process.

2. "Melt Extrusion" in Powder Coating Production Technology

The mixing of powder coatings involves several steps, which are completed in separate equipment.

At this stage of production, the base material and curing agent (not necessarily present) are melted and mixed at the molecular level, and the pigment clusters are crushed into raw particles and uniformly dispersed together with additives in the melted base material/curing agent mixture. Global Coatings Network has learned that the surface of pigment particles is simultaneously wetted by the molten base material. In principle, there are three types of machines that can be used for hot melt extrusion. Although Z-shaped blade kneading machines and heated twin roll grinding machines can also be used, the most important equipment is still the extruder.

The mechanical equipment commonly used for producing powder coatings includes single screw extruders, twin-screw extruders, and planetary screw extruders.

3. "Fine Grinding" of Powder Coating Production Technology

The paint manufacturer should perform fine crushing after hot melt extrusion. Powder coating manufacturers will use different types of crushers to ensure that the particle size of the coating meets the desired range, all of which are manufactured using the principle of grinding.

The contemporary crushing system is supplied as a complete set, which includes particle size classifiers and dust collectors.

4. Powder Collection and Dust Removal in Powder Coating Production Technology

Usually, side filters are used or a combination of cyclone separators and side filters is preferred to collect fine powder from the air classification outlet. The dust collection device for powder coating depends on the factory's output and the type and color variety of powder coating. The tail dust filter can improve the reliability of crushing and grading operations and improve pollution control almost without maintenance work.

5. The "Multi Cyclone Powder Recycling System" for Powder Coating Production Technology

Due to various reasons such as electrostatic spraying of powder coatings, there will always be some powder that is not fully utilized. To solve this problem, the industry has developed a multi cyclone powder recovery system. Its function is to collect the powder that falls during the spraying process, separate it into usable powder and unusable waste powder, and send them separately to the corresponding devices.

4、 What is the current state of the powder coating market in China?

At present, the market share of powder coatings in China is relatively small compared to other types of coatings. However, in the relatively mature field of industrial coatings, powder coatings are one of the few products that can maintain a high growth rate.

Powder coatings have three main markets in the world, namely Europe, the United States, and Japan, but due to historical reasons and factors in raw material utilization, these regions have developed their own different product systems.

In the United States and Europe, carboxylic acid polyester and epoxy resin based materials are used for indoor applications; Mixed type; Powder coating is the most popular. In North America, lawn and garden facility products are also an important market, accounting for approximately 7% of the entire powder coating market share. The ordinary metal surface coating industry is the largest market for powder coatings, accounting for about 50% of the entire market share.

The home appliance industry is an important application area for powder coatings, with applications in household appliances accounting for 17% of the entire powder coating market in the United States.

In recent years, the application and development of powder coatings in the automotive industry have also been very rapid.

Other market applications of powder coatings include anti-corrosion powder coatings used in pipelines and for enhancing threaded steel bars. This type of powder coating is mainly based on pure epoxy systems (fusion bonding type). This type of powder coating variety is almost ignored in the European rebar market, and both in terms of technology and market demand, this market field still has broad development space.