Blue paint suddenly has white in it!

[MisterBoy]

I've been using Ronseal weatherproof wood paint in royal blue gloss on my front door.

I put two coats on a couple of weeks back and kept the same brush in an airtight container.
Came back today to do some final touches and suddenly noticed I was getting white streaks... Both in the brush and in the tin it looked like white paint had got in.
I switched to a brand new brush and restirred the tin thoroughly but it happened again, like my new brush had been used for white paint.

It's definitely coming from either the tin or the brush had anyone ever heard of this?
Can't tell until it dries if the new coat is actually slightly lighter or I've got away with it

 

[Harry Bloomfield]

Check the label on the tin, does it say stripey paint?

 

[MisterBoy]

Check the label on the tin, does it say stripey paint?

weren't stripes in it last time Do you think someone snuck some in.

 

[sparkwright]

Unless it's woodfiller, Ronseal is crap.

 

[MisterBoy]

Unless it's woodfiller, Ronseal is crap.

None of the reviews, good or bad I've read mention it getting white streaks. So I think whether it's good or bad paint probably isn't the issue here.

For all the world it looked like I'd used the wrong brush but I had checked carefully. I'm trying to think if something else could get in to cause this - a flake of white paint or something - but I'm pretty careful.

 

[sparkwright]

Daft question, but did you stir it?

 

[MisterBoy]

Daft question, but did you stir it?

Yep. I stirred before I started but it hadn't really separated (if that's the right word) anyway.
When I noticed the white I stirred again but it came back. I tossed the brush, got a new one and stirred again and it happened again... That was the really odd part.

I think I'm going to decant it into something to see if I can see anything weird, and try again.
The good news is apart from one small spot, it's dried ok. I was very worried after spending a day getting it all done properly with two coats, I'd ****ed it up at the final hurdle with some finishing touches it didn't even really need, trying to get it perfect!

 

[sparkwright]

Water-based or oil-based?

 

[MisterBoy]

Water-based or oil-based?

I'm pretty sure water.

Do I poured it into another container and no sign of anything weird. Have to conclude either I got some contaminant in, or the paint in the brush had broken down between the bristles... Using the trick of wrapping the brush up rather than trying to fully clean and dry it. But I guess you can't stir the paint held in the brush so if that separates...