Colour Coated Aluminium Coil Paint Thickness Influencing Factors And Control Methods

Paint thickness of colour coated aluminium coils

Paint thickness of colour coated aluminium coils is one of the most important factors affecting their performance and quality. Too much or too little paint thickness can lead to defects and problems in colour coated aluminium coils. Too large a paint thickness will increase the cost, reduce the hardness and flexibility of the coating, affect the adhesion and corrosion resistance of the coating, and easily produce defects such as sagging, wrinkles and bubbles. Paint thickness too small will reduce the coverage and hiding power of the coating, affecting the colour and gloss of the coating, easy to produce scratches, abrasion, flaking and other defects.

Factors affecting the paint thickness of colour coated aluminium coils and control methods

Therefore, controlling the paint thickness of colour coated aluminium coils is a key part of ensuring their quality and performance. The paint thickness of colour coated aluminium coils is influenced by a number of factors, mainly the following:

Quality of raw materials and surface treatment

The quality and surface treatment of raw materials directly affects the bonding and flatness of the coating to the substrate. Raw materials should be selected with appropriate alloy series, hardness, thickness and other parameters, and cleaned, pre-treated and primed (fine) coated to improve corrosion resistance and adhesion to the upper layer of paint film.

Types and Properties of Paint

Different types and properties of coatings have different requirements for the thickness of the paint applied. Usually classified according to the paint used to make the organic coating, there are PVC coated aluminium coils, polyester coated aluminium coils, acrylic coated aluminium coils, fluorocarbon coated aluminium coils, silicone polyester coated aluminium coils and so on. Among them, fluorocarbon coated aluminium coils are the highest grade products with the best weathering and UV resistance, but they also require a higher paint thickness, generally 25 microns or more.

Painting process and equipment

Different coating processes and equipments have different control accuracy for coating thickness. According to different coating methods, there are organic coated aluminium rolls made by roller coating, spraying, powdering, laminating and printing.4 Among them, roller coating is the most commonly used method, which evenly distributes the pre-mixed paint on the substrate through rollers, and forms a continuous and uniform paint film through baking and curing. Parameters such as the shape, size, rotational speed, and clearance of the rollers affect the number and distribution of the rollers, and thus the thickness of the paint applied to the final product.

Summary

To sum up, the paint thickness of colour coated aluminium coil is a complex and important issue, which needs to be considered comprehensively according to the use of the product, performance requirements, cost control and other factors, and appropriate measures should be taken to monitor and regulate. Generally speaking, the standard paint thickness range for colour coated aluminium coils is 15-25 microns.