Factors and solutions for paint floating and blooming

There are many floating color flowering factors of the coating, mainly pigment particle size, the surface pressure of each material in the formulation system is poor, pigments, dispersants, moisturizers and emulsifiers hydrotherapeutic oil balance value (HLB), emulsion and color paste compatible, conceding thickeners and other floating hair flowers of the coating caused a greater impact.
1, the effect of the particle size of the pigment
coating film in the process of drying the film, there is a higher than the surface area of the finer pigment particles easy to move to the surface, and the relatively low surface area of the pigment coarse particles are easy to precipitate, resulting in different particle size of the pigment in the film when floating phenomenon. The solution is to carefully select the pigment, filler, and grind and disperse to the appropriate particle size to avoid floating

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2, surface difference effect
in the process of dispersing pigment slurry, due to the surface polarity of various pigment fillers are not the same, in order to achieve better dispersion stability, the type of dispersant selected is not the same. For example, when dispersing white pulp, anion-type dispersants are usually used, while other pigments are mostly non-ion dispersants, or used in collaboration with some anion dispersants, because their pigment surface adsorption of different dispersants, so its hydrohydrate affinity value and surface strength are not the same. For example, when dispersing the slurry, add Greesol ES400 moisturizer to reduce the surface pressure difference of various color slurry to improve the floating flowering phenomenon.
3, phase solubility between systems
when the pigment particle surface adsorption surfactant and emulsion particle surface adsorption surfactant i.e. emulsizer and water affinity is different, if the pigment particle surface adsorption When the affinity between the surfactant and the water is large, the surfactant adsorbed on the pigment surface will desorpt, making the protective layer of the pigment particle surface thin, resulting in the pigment flocculation, which causes the paint coating film floating flower. When the emulsifier on the surface of latex particles is compatible with the surfactants in the color paste and filler particle surfaces, then the emulsion is good for wetting these faces and filling particles, and the color display of the whole color paint is good, the color is bright, and does not float.
4, the effect of hydro-oil balance
Hydro-hydro-oil balance (HLB) is a very sensitive issue, in the production of coatings using a variety of materials: emulsions, pigments, fillers, solvents, solvents and various additives. These materials have their own hydromassive oil balance value (HLB value), each material hydromassive oil balance value matching the performance of the entire system of coatings is very good, floating color, flowering, water and other phenomena will be overcome. Of course, we use emulsion, pigment selection, hydromassive oil balance value, that is, HLB value can not be changed, but you can carefully select additives, that is, wet dispersants, thickeners, etc. to adjust the HLB value of the entire system, so that the HLB value of the entire system balance. So when we disperse pigments, we must first understand the HLB value of pigments, to choose the HLB suitable dispersant. For example, for low HLB carbon black, molybon series pigments, we generally recommend the HLB value of the same Greesol DPB, DPB40 dispersant, for high HLB value of titanium dioxide, iron oxide series pigments, we recommend the use of GreesolDPI, for red and yellow pigments, we recommend the use of Greesol DP1600, DP1900. If the paint in the storage process appears floating white phenomenon, may be the HLB value of the white slurry is too oil-friendly, then you can add HLB-value hydro-friendly moisturizers and dispersants in the formulation of the white slurry, if the paint in the storage process appears to float other pigment colors, said that the HLB value of the slurry is too hydro-hydromassive, the need to add HLB-value hydrolytic moisturizer or dispersant in the white slurry.
5, the effects of thickeners
some of the false plastic thickeners and HLB value of larger surfactants have a strong affinity, so that its surfactant pigment surface dissociated, resulting in pigment particles aggregation and flocculation, so that the coloring force decreased and the production of floating flowers. In the system of organic and inorganic pigment coloring, especially when titanium white and indistinct blue, indistinct green and carbon black slurry color, you can choose a combination thickener with weak false plasticity to obtain a more satisfied color coating and have good leveling. The hydrophobic base group in the thickener has a strong affinity with the pigment particle surface, and the surface of the adsorbent pigment particle forms bridge flocculation, poor coloring force, and causes the paint to float. These need to be considered in formulation design and tested to select suitable thickeners to avoid floating colors.
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