Paint sinking mainly refers to color paint, the reasons are:
(1) The storage time is too long. The color paint is stored for too long, and the pigment often forms hard lumps at the bottom of the container due to its high specific gravity. For this reason, in addition to turning the bucket upside down during the storage process, the paint bucket should be placed horizontally, vertically and shaken several times every few days to prevent the pigment from settling.
(2) The storage temperature is too high. The storage temperature of general paint is advisable at 2o ~ 25 ℃. Because the suspension of the pigment in the paint will be destroyed if it is above 28°C, the paint will reduce its viscosity and precipitate and agglomerate.
(3) Add too much diluent. If there are too many thinners in the paint, the pigments will easily precipitate.
(4) The pigment particles in the paint are too coarse, and the grinding and dispersion are not uniform enough to cause precipitation and agglomeration.
(5) The polymerization reaction of the base material will cause gel and produce precipitation.
For paints with light precipitation, the paint can be fully stirred with a wooden stick before use. If the pigment has formed hard lumps, open the lid of the barrel, pour out the thinner, then stir it effectively with a wooden stick, then add the thinner and mix well, and it should be filtered through a fine sieve before use.