November 15, 2022
The durability of the coating is the performance of the color-coated board during use, which is usually measured by the aesthetic life and the overhaul life:
Beautiful surface life
The time interval from the date of completion of the color-coated board to the appearance of a certain degree of discoloration and chalking of the surface coating, which affects the original aesthetic effect of the coating.
Limited life
The steel plate is corroded and perforated and cannot be used.
Coating thickness
1. Poly and hollow tissue coating
Microscopically, the coating is a porous structure, and water and corrosive media (chloride ions, etc.) in the air will invade through the weak part of the coating, causing corrosion under the film, and then the coating will blister and peel off.
2. Coating thickness selection
According to the experimental results: the front coating ≥ 20μm can effectively prevent the intrusion of corrosive media. Since the anti-corrosion mechanism of primer and top coat is different, the thickness of primer (≥ 5 μm) and top coat (≥ 15 μm) are required respectively. Only In this way, the corrosion resistance of different parts of the color-coated steel plate can be guaranteed to be balanced.
Coating gloss
1. Light pollution
High gloss surface glare High reflectivity of sunlight during the day can cause light pollution.
2. Potential safety hazards
The high-gloss surface has a small friction coefficient and is easy to slip, which is easy to bring safety hazards during roof construction.
3. Visual fatigue
The aging of color-coated steel plates when used outdoors first means loss of gloss. When maintenance is required, the old and new steel plates are easy to distinguish, resulting in poor appearance; if the back paint is high-gloss, it is easy to produce halo when there is light indoors Visual fatigue.
Experiments show that: under normal circumstances, the color-coated boards for construction mostly use medium and low gloss (30-40 degrees).
1. Light color system
From the technical point of view, the choice of pigments for light-colored paints is large, and inorganic paints with superior durability (such as titanium dioxide, etc.) can be selected, and the heat-reflecting ability of the paint is strong (the reflection coefficient is twice that of the dark paint). Summer paint The temperature itself is relatively low, which is beneficial to prolong the life of the coating. In addition, even if the coating is discolored or chalked, the contrast between the light-colored coating and the original color after the change is small, and the effect on the appearance is not large.
2. Dark colors
Dark colors (especially bright colors) are mostly organic colors, which are easy to fade when exposed to ultraviolet rays, and the color changes in the shortest 3 months.
Experiments show that: according to relevant experimental data, when the outside temperature is the highest at noon in summer, the temperature of the white surface is 10 degrees lower than that of the blue surface and 19 degrees lower than that of the black surface, and the reflection ability of different colors to sunlight is different.
