Coating deposition and caking phenomenon causes and measures2016.09.19 10:32
01 / coating precipitation agglomerate
Coating in the process of storage, the phenomenon of sinking to the bottom of the container, the solid component is called precipitation, also known as the sink to settlement. When the precipitation phenomenon is serious , coating the pigment particles precipitate into with mixing methods, such as not easily dispersed dense clumps, referred to as the lump.
02 / coating precipitation and caking phenomenon
When coating open barrels, stir with a stick into the bucket, mention, if the adhesive coating color consistency, no precipitation phenomenon. If the thin under At the bottom of the thick, feel difficult to stir up, namely the precipitation.
03 / coating precipitation and agglomerate
The pigment grinding is not fine, scattered; In the formula, YanJi ratio is too large, fillers density factors, such as easy cause precipitation. Due to join dilute Too many release agent, coating with low viscosity, coating lost the surface of the normal state of suspension, fillers precipitation. Between pigment and resin to produce a chemical Polymerization or mutual adsorption, gel, precipitation. Storage time is too long, more than the retention period of the coating, especially the long time rest place. Paint storage time is too long, fillers for density is big, in the bottom to form the precipitation, eventually forming scleroma. Metamorphic occur some resin. storage Temperature is too high, storage temperature of the paint in 15 ~ 25 ℃ advisable. More than 30 ℃, some pigment and resin suspension property was damaged in the paint coating Material viscosity reducing and precipitation agglomerate.
Considered in design of coating formula, suitable YanJi ratio, average YanJi than not more than 2:1, special varieties. Fillers as far as possible choose density Smaller, less use or replacing discretion with low density fillers. The viscosity of the paint can't too low, choose between fillers can't react. Born in coating Intrapartum, using suitable equipment, grinding scattered as far as possible even, viscosity, degree of fineness to regulations. Join anti-settling agent in the coating, use a small amount of additives Special performance, make thixotropic coating, change the coating state of suspension. Paint storage should be placed in a cool ventilated place, will shake bucket placed horizontally, the horse, or on a regular basis Move a few times. Pay attention to the coating of the storage period. Available for coating has precipitation, manual or mechanical stir well before using. For agglomeration phenomenon, should be Put out flow section, from the bottom of the container by spatula scooping up precipitation, ground, then pour the liquid medium back to the original barrel, fully mixing.