If you ever experienced an early solidification with Caffélatex (or another sealant), chances are that there's nothing wrong with the sealant itself, but you might be victim of the sneaky "hair dryer" effect.
Beside the use of CO2(described here) or contamination of your sealant with other products(described here), the “hair dryer” effect is a common but little-known reason for the decrease in a sealant lifespan.
When does it happens?
If a tubeless tyre doesn’t immediately inflate after having inserted the sealant, some people using a compressor might be tempted to insist on blowing air into the tyre for a long time (and here the analogy with an hair dryer), until the tyre actually starts to inflate.
Technically, what is this “hair dryer” effect?
If the sealant is exposed to a forced evaporation caused by the fast air-flow (if the valve is on a 6 o’clock position, the sealant takes the air blow in full force), polymerization starts on the surface of the sealant. Looking at it, it reminds of curdled milk.
What are the consequences?
If there’s plenty of Caffélatex sealant inside the tyre, the low solidified quantity doesn’t have any influence on the sealant life span. On the other hand, if there’s only a minimum amount of Caffélatex, the tyre can still inflate and hold air, but there’s hardly any liquid sealant left for puncture prevention.
How to avoid it
If the tyre doesn’t start inflating after ten seconds of blowing air, it’s better to try a ‘Pro’ trick: wet the tyre beads with soapy water, remove the valve-core and blow air directly through the valve stem to maximise the air flow.
It is also recommended to try and inflate the tyre before adding the sealant. This way any major air leaks can be detected without wasting the sealant.