We often see some rockeries. They have only been completed for two or three years. Some have faded into cement color, and some have even shelled. Fading has a great effect on rockery. First, it affects the beauty of rockery. Secondly, it has lost the protection of the color layer, greatly reducing the water resistance of the rockery. Xiao Bian analyzed more than 100 cases in the industry and found out the reasons why rockeries are easy to fade. I will explain to you today.
We found that the plastic stone rockery produced in winter is more likely to fade in the later period. Through comparison and analysis, it is concluded that the plastic stone rockery produced in winter has a high anti alkali rate, which will greatly damage the color layer and cause the color layer to fall off. The anti alkali is mainly related to the cement used in the surface of the rockery. Under the condition of low temperature and high water ratio, Portland cement will penetrate into alkali after solidification. Before painting on the mountain, adding alkaline primer can reduce the occurrence of anti alkali.
There are also several reasons why rockery is easy to decolor:
1. The choice of paint is wrong. The pigments commonly used in the rockery industry are: iron oxide pigment, acrylic pigment, water-based color paste and paint. Among them, acrylic pigment is a kind of painting pigment, which is suitable for indoor places. Its anti ultraviolet ability is poor, and it is not easy to use in outdoor rockery; The compatibility between paint and cement-based materials is poor. It can be applied to indoor places. When applied to outdoor rockery, the skin will explode under high temperature.
In the outdoor state, the wrong choice of the color of the rockery is the main reason for the color fading of the plastic rockery. In the construction process, we only considered the easy color matching of propylene pigment, but did not know the poor weather resistance of propylene pigment.
2、 Do not wash before painting. Before the rockery is painted, the surface of the rockery shall be carefully cleaned to avoid dust and gravel. If dust and gravel are left on the mountain surface, they will be used as isolation materials to separate the mortar layer and color layer of the rockery. As time goes by, the effect of sun and rain will peel off the color layer, causing the rockery to fade.
3. Most of the anti ultraviolet additives in the pigments are cement based materials on the surface of plastic stone rockery, and the selected pigments are mainly water-based materials. In these water-based materials, weather resistance is one of the main conditions to be considered. The outdoor environment is inevitably exposed to sunlight and rain water. Latex paint and color paste cannot be kept for a long time, so anti ultraviolet additives are crucial. In some plastic stone rockery projects, in order to save costs and reduce the use of weather resistance and UV resistant lotion, the color will gradually fall off in the next five years.