Acrylic pigment emulsions are a type of coating composed of acrylic resin, pigment, water and other additives. They have good water resistance, weather resistance and chemical stability. Under normal circumstances, they can maintain good performance for a certain period of time.
When acrylic pigment emulsions are exposed to air for a long time, the organic components in them will gradually decompose. Over time, the pigment particles will slowly lose their binding force, resulting in a powdery substance, which is the phenomenon of powdering. The degree of powdering is affected by the quality of the pigment, the formula and environmental factors.
During long-term exposure to air, acrylic pigment emulsions will shrink and expand due to factors such as temperature changes, humidity differences and ultraviolet radiation. This shrinkage and expansion process will cause stress in the pigment film, and when the stress exceeds a certain limit, cracks will appear. In addition, the thickness of the pigment layer, the drying speed and the properties of the base material will also affect the occurrence of cracks.
The weather resistance of acrylic pigment emulsions is the key to maintaining good performance. Ultraviolet rays, oxygen in the air, humidity, etc. will all have an impact on it. For example, ultraviolet rays can cause photochemical reactions in pigment molecules, accelerating the aging of pigments. Humidity can affect the drying speed and stability of pigments.
In order to maintain the good performance of acrylic pigment emulsions, some measures can be taken. For example, antioxidants and ultraviolet absorbers can be added, which can slow down the oxidation and photochemical reactions of pigments. At the same time, during use, the thickness and drying speed of the pigment layer should be reasonably controlled to avoid cracking due to over-drying.
Under different environmental conditions, the performance of acrylic pigment emulsions will be different. In dry and high-temperature environments, powdering and cracking may be more obvious; while in humid and low-temperature environments, its performance may be relatively stable.
Acrylic pigment emulsions do face problems such as powdering and cracking when exposed to air for a long time. However, through reasonable formula design, adding appropriate additives and taking effective protective measures, its good performance can be maintained to a certain extent. In practical applications, we need to select suitable acrylic pigment emulsions according to specific conditions and do corresponding protective work to ensure that it can maintain stable performance when exposed to air for a long time.
