Help! Paint is weird under black lights!

TheShanMan

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Painted my game room blue with paint from home depot. I ran a little short so I went back for more and they reformulated it to include primer. Looks good under regular light but totally different under black light - much darker than I'd like. So I went to Sherwin Williams to see if I could get something from them that would be closer to the original paint. If anything it's even darker than the new HD stuff.

Then I got to thinking that when I used the original paint with a brush to touch up some spots (I rolled the room), those touch up spots looked darker, so maybe that's why the Sherwin Williams stuff looked dark (I tested it with a brush). I then tried the original paint with a mini roller - again, too dark! So I can't make any sense of this.

I really liked the lighter look of the original paint. Anyone have any clues as to why I can't seem to get that look again? I sure would appreciate any tips or explanations as to what's going on. I'd love to get that same look with the areas that still need to be painted but at this point I'd settle for doing a fresh coat in the whole room if I could at least figure out how to get it to look lighter even if it doesn't perfectly match the original.

If you look at the pic, the darker area to the left is the new HD stuff and the blob of dark above the outlet is the SW stuff. The difference is more dramatic in person, btw.
 

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The paint is probably accumulating, so even if it's a lighter color some of the darker underneath is showing through. I hate to say it but your best bet is to do a coat of primer and then reapply the blue.
 
If I read you right, you've got it backwards. The lighter stuff is underneath and when I try painting the different paints on top of it, it gets darker, so there isn't anything "darker" to show through. Besides, there was one area of a wall where the texture looked too dramatic so I tried to "soften" the texture with a bunch of coats (maybe 5?) when I originally painted the room. That doesn't look dark like this stuff is so I think that eliminates any explanation of "accumulating", doesn't it?

I can't imagine doing a coat of primer and 2 of paint all over again in a 600+ sq foot room. I sure hope it doesn't come to that and I'm not even sure if I'd be willing to do that given how much time I've spent working on this room as a whole (not just painting the walls). I'm so sick of this project it's getting tough to keep plowing forward at this point.
 
UV reacts with phosphors in the paint, and why white paint/clothing glows tremendously under blacklight while dark blues and reds do not (unless they are specifically UV reactive).

I wonder if initially on the first coat, it was thin enough to expose the underlying white primer or previous paint coat and each time you go over it's simply reducing the amount of UV that can hit the underlying coat.

Try on a spare board to paint it bright white, THEN overcoat with your blue(s). Otherwise you may need to ask them to add in some UV reactive blue dye or particles or find a place where you can purchase and add yourself).
 
Like I said, there was a section of my wall where I coated it a BUNCH of times and it still looks light in the black lights, so it's not a matter of underlying primer and/or paint showing through. I had that same thought until I thought to check that area.
 
If I read you right, you've got it backwards. The lighter stuff is underneath and when I try painting the different paints on top of it, it gets darker, so there isn't anything "darker" to show through. Besides, there was one area of a wall where the texture looked too dramatic so I tried to "soften" the texture with a bunch of coats (maybe 5?) when I originally painted the room. That doesn't look dark like this stuff is so I think that eliminates any explanation of "accumulating", doesn't it?

I can't imagine doing a coat of primer and 2 of paint all over again in a 600+ sq foot room. I sure hope it doesn't come to that and I'm not even sure if I'd be willing to do that given how much time I've spent working on this room as a whole (not just painting the walls). I'm so sick of this project it's getting tough to keep plowing forward at this point.
Hmm. That is quite weird. Have you considered getting some clear blacklight reactive paint? They make transparent varieties now that can be added to solid colors to give them more reaction under blacklight.
 
I suppose that could be a solution but that would mean 2 coats - one coat of regular paint to get a consistent look throughout the room and one coat of the reactive stuff. I would also have to find a clear satin as that's the most sheen I want. And the powder isn't cheap.

I've actually gotten some to play with. But I decided it wasn't going to be worth the cost and effort. Part of that decision is out the window now of course since I have to find some way to fix this, but it's still a lot of effort and money. I'd much rather understand what is happening with the paint and thereby figure out what I'm doing wrong. I can't be the first person to run into a problem like this and I'm hoping someone has figured it out.

That gives me an idea though. I might try contacting one of the companies that sells the powder. Seems like contacting those type of people would give me the best odds of learning what is happening and finding out what the solution is.
 
Since you said that one batch did not have primer and the latest batch was reformulated to include primer, I'm going to guess that that has something to do with it. I don't understand why, but it's the only difference between the two.

To have uniform color under the blacklight, you will probably have to repaint the entire room, first with primer and then with the SAME paint. To figure out how much paint you will need, you will need to measure the square footage of the room. A gallon of paint will cover about 350-400 square feet. I always figure the lower coverage so when I am done, I have a partial gallon leftover for touch-ups.
 
See that's the thing. I figured the same thing too. Since it's impossible to get the original paint (believe me, I tried really hard to do that), I went to SW on the assumption I'd be doing the whole room but if I got lucky, it would look like the original.

But that's where things got confusing. It looked worse if anything, so I tried rolling the original (good) paint with a mini roller and it didn't look light anymore. Nor did it when I brushed it. So I have no idea why I can no longer get the same look with the paint I originally used.

I was hoping this thread might result in someone giving me a lesson about how the blacklights do something different in different circumstances that might somehow reveal what the problem is.

I suppose it might be worth doing a small test with primer, then a couple coats of the new paint if no other bright ideas come up. But the thought of having to do the whole room with 3 more coats kills me. I don't know if I could motivate myself to do that much rework at this point in the project. :(
 
I'd personally just try to blend it so there's no noticable line... or make one wall the same from corner to corner, even if the other walls don't match. At least it wouldn't be very noticable. Or maybe try Lowe's and see if you can get one similar to the original HD one you got (same quality grade, no primer).

I'm sure it's just small differences that aren't really specified since very few people care how paint looks under a blacklight. When they color match paint, they're trying to match the color in normal light. They do usually have different light sources in the paint area to you can see how it'll look with natural, fluorescent, etc... maybe take a small blacklight with you and see if you can find one that glows more than the others and try that kind. It'll probably be pretty tough to find one that matches perfectly though.

DogP
 
I agree with repainting the entire room...I know it sucks to have to do that, but at least you know what to expect after having done it. Plus, take a few minutes to think what worked and what was a pain in the ass the first time you painted. Perhaps a new wall-order might work better for you (clockwise vs counter clockwise, or opposite walls, and keep in mind how your right- or left- handedness might mess with this order as you paint). In the grand scheme of things the cost of the paint would probably be $60, so not a lot of money compared to the nagging feeling in your brain each time you go down and see your current paint woes.

Also, I'd do primer and 2 coats of color. Make sure you over buy on the color by a quart or so, too, so you have no worry of running out. And when you get your color, also get a 5 gallon bucket with lid and mix all gallons of your color together in there instead of doing one can at a time. This will ensure you are truly using the "same paint" for the entire room. Paint is much better these days and you don't have to be so careful about it under normal lighting, but black lights are a different story and will show differences even in the new computer-mixed paint.

If you have to stop painting at all and do it all in one shot, make sure you finish on good dividing line - like a wall corner or strip of moulding. This way it "hides" the stop and start better. When you are painting, make sure you are always putting wet on wet, too - especially when cutting in. I usually cut in the floor and ceiling only a couple feet at a time, then paint the rest with roller. Don't worry, you'll end up being a pro at this and get faster and faster.

Overall, take every precaution you can because a black light will show every flaw you make. But, also keep in mind that eventually you will put stuff on the walls and have games in the way to cover up some mistakes.
 
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I'm a little confused. You painted, ran out, went back to the store, and had to get a different formulation, to include an imbedded primer. You mention that you tried to get the original but could not. Did you have the original new in can for a while and they stopped selling it? Then you want to Sherwin Williams for yet a third paint. Correct?

The problem is the mix of formulas. It's been a while so specifics are fuzzy but black ligts work via combo or reflected light waves off of a material and absorbed waves reacting with same material and releasing energy. Don't hold me to the physics...I forget more than I ever remember..Google is my friend. Anyway, you get the general idea.

If you have a mix of material, no matter the pigmentation to match color in white light, I can defiantly see where it would react differently in black light.

I agree with the other folks, your going to have to consistently coat the room for a consistant look. Re-paint.
 
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