Pigment Paint Floating Color Problem
Pigment blue 15:0 manufacturers say that color float is a frequent problem in paint production, especially when there are multiple pigments in the formulation, the phenomenon of pigments separating from each other will occur, and pigment separation will lead to uneven distribution of pigments on the surface of the coating after drying.
Flowering is the horizontal dispersion phenomenon of pigment mixture, mainly due to the different surface tension of different pigments in the coating formula, the affinity between pigment and paint is not the same, resulting in uneven distribution of film color and pigment concentration in the horizontal direction of the surface of the paint film, and the concentration of local pigment is too much, resulting in the appearance of the film in the form of mesh and stripes, such as irregular flower spots.
Floating color is due to the density and particle size of the pigment used in the production of paint and the different degree of wetting, paint in the film forming and drying process of pigment mixture components separated from each other, the pigment mixture in the vertical direction of the dispersion of the change, some floating to the surface, some other in situ or to the bottom of the immobile or sinking.
Pigment floating color bloom test method
● Compare the coloring power of spraying paint film and scraping paint film to judge the floating and blooming condition.
● Apply the paint film on the glass plate to observe the floating color blossom situation.
● Use the finger to wipe the half-dry state of the coating film, by comparing the color difference between the paint film in the rubbing area and the original paint film to determine the degree of floating color blossoming, which is also an indicator to reflect the flocculation.
Main factors affecting the floating color efflorescence
●The surface state of the pigment and the affinity of the paint, the wettability is not good or the water content is high, it is easy to produce floating color bloom;
●The particle size and density of pigment, the bigger the gap, the easier to float color;
●The dispersion of pigment, the pigment in the system is not sufficiently dispersed, resulting in the flocculation of pigment and produce floating color;
●Solvent evaporation speed and the amount of solvent, solvent evaporation is slow and solvent amount is big and easy to produce the flower;
●The drying speed of paint and the ratio of pigment and base material, the slower the paint dries and the smaller the ratio of pigment and base material, the easier it is to produce floating color blossom;
●Thickness of the paint film, the thicker the paint film, the easier it is to float colors and flowers.
Floating color blossom is a common phenomenon of paints especially for dark color paints. Manufacturers should carefully choose suitable pigments, fillers and solvents according to the formula of paints, and the particle size of the selected pigments and fillers should be matched; control the proportion of pigments and base materials and the thickness of paint film; use dispersants or other additives to reduce the occurrence of floating color blossom.