Sour Latex Paint???

[Carroll Courtney]

Guys I have about 3gals of latex left in a 5gal plastic container which was purchase about 2yr ago.At the beginning I painted the ceilings downstairs than yr later I went to start painting the upstairs until I open up the container:eek: Dang does it stinkkkk,will the smell dissipate or should I just trash it???I hate wasting paint but I don't want to smell it from now own either.Just wondering----Carroll

[John TenEyck]

Yeah, that can happen if you spit in the paint when you're using it ! Just kidding, but it is bacteria growing. Try stirring an ounce of bleach into it. It should kill the bacteria, and if it doesn't curdle the paint it should be usable. Try it on a scrap piece of something to make sure though.

[Phil Phelps]

Did it ever freeze?

[Carroll Courtney]

I did not think of it freezing,we did have afew nights/days that it was @ freezing temp.Bleach,I'll give it a try,thanks guys---Carroll

[Rich Engelhardt]

99.99% of all latex sold these days can go through several freeze/thaw cycles.
In order to "hard freeze", latex paints need to get down to nearly 0*F. They usually have enough glycol content to prevent a hard freeze in temperatures that are in the 20's or so. If the material got down to 32*F, or even a couple degrees less, it would take an extended amount of time at that temperature before it got "spongy".

Yes - latex - or even any other organic (even oil) can decompose. Latex ususally smells like,,well,,,vomit once it's soured.

A small amount of Lysol will stop the process and be a bit safer than using bleach.
Most latex materials will contain ammonia in one form or another.
Ammonia is the solvent for latex.

Mixing ammonia and bleach - even at the small amounts being used here - isn't the best idea. It forms chlorine gas.
Even amounts as low as 3 to 6 ppm can cause irritaion of the eyes.

A drop of vanilla extract will help mask the odor, BTW.

[John TenEyck]

Uh - oh, I forgot about the reaction of bleach and ammonia. Thanks for pointing that out and offering a safer alternative. My bad, and my apologies to the OP.