But seriously folks,...
It just means a paint that comes as two separate chemicals and hardens when mixed together.
We Yanks would call it a two-part paint but you don’t hear the term used much anymore in automotive paints because, over here, practically all car painting is done with two-parts these days.
All factory paints are two-part systems these days, at least for top coats. So if you’ve buffed a new car within the last ten or twenty years or so, you’ve buffed two-pack paint. Pretty much the entire re-spray industry has converted to catalyzed urethanes too, at least in the US, UK and Europe.
In SoCal it’s illegal to even sell or shoot solvent-evaporation cured auto paints.
Catalyzed coatings tend to be significantly tougher and harder than solvent-evaporation cured finishes. When they were first introduced everybody had to get used to them. Now they’re the norm and we think of old lacquers and non-catalyzed enamels as soft.
PC.