whats the meaning of House & Trim Paint Base 1,2,3 or 4

what does the different base #'s mean, I searched and even checked a few manufactures sites but no one described the differences or defined the term..

 

A base is a paint medium specifically manufactured for mixing colors.

Typically, base 1 is for pastels, 2 for slightly darker, on to base 4 which is used for intense darker colors.

Aside from different formulations for each base, base 4 allows more room in the can for the addition of tinting colors than base 1.

The reason you can find so little information on the bases is simple - they're not meant to be sold "as-is", they are used to formulate a chosen color.

If you're REALLY interested, most companies can furnish MSDS info on their bases as is.

PS - If you mix a color in base 1 and use the same formula in any other base, you won't get the same color...

 

Very well put George
The #s on the base are for the paint tinter's information
Usually there's no need for us to know the difference, as they are not meant to be used w/o tinting

 

good info thank guys

 

As George said, the difference between bases mostly comes down to titanium dioxide fill level. TiO2 is the white pigment used to give paints their whiteness and hiding power (other fillers, such as talc, add a little whiteness as well). "White base" paints (the sort you'd buy off the shelf to use as white) can contain 30+ percent of their solid content in TiO2. Medium or mid-tone bases have less TiO2 (maybe 10-15%) while clear or deep-tone bases have absolutely no TiO2 (meaning that the paint would dry almost clear if you used it untinted).

As you can imagine, it would be nigh impossible to darken a can of white paint into the deep toned colors that we often see without overflowing the can and diluting the other ingredients beyond their useful limits, and so the base system allows the retailer to add all of the colorant right there in the store.