Product: Paint
Colour Change Paint   (+4)  [vote for, against]
Paint that changes colour significantly when dry

Like the fool I am I decided to decorate my bathroom over the holidays (stripped the 2 layers of paper on the walls, removed the gloss paint that was underneath - don't ask me who put that there, on a <blank> wall - then removed the other two layers of paper below, put up fresh paper) and today have been painting the walls.

Trouble is, since the bathroom is small and difficult to negotiate on top of a ladder, it has been murder trying to see where I have painted the second coat. What I would have sold my own grandmother for is a paint that changes colour significantly as it dries (for example from vomit green to the delightful meadow blossom yellow that now resides on my walls). This could easily be achieved through the selection of the right solvents and pigments, would have saved my neighbours from hearing numerous expletives, and would have saved on decorating and subsequent laundry time.

Now I know that some people will be upset that the initial colour on the walls does not match the colour on the tin, so will need clear labelling etc., and maybe should be placed on the high shelf in the DIY shop.

Excuse the rant surrounding my idea...
-- suctionpad, Dec 27 2003

Dulux Magic White!
This is the paint i mentioned in my comment, your dream made reality! [UndeadWario, Oct 04 2004, last modified Oct 21 2004]

Colour Change Paint http://www.paintwit...olorchangestore.htm
Buy colour changing paint here. Shipped Internationally [paintwithpearl, Jul 22 2008]

(?) Chameleon Color Flip Flop Changing Paint
These guys make color changing paint that changes on viewing angle and temperature. Cool stuff! [KustomKat, Nov 01 2010]

-- neilp, Dec 27 2003

"WET PAINT (until yellow)"
-- FarmerJohn, Dec 28 2003

"TRUST me, it looks better when its dry ..."
-- Letsbuildafort, Dec 28 2003

Thoroughly baked I am afraid. Some paints (for example the white wall paint I saw applied in Kabul) smell like they contain fish oil. When this paint goes on the wall it is practically clear but over about 4 days as the paint cures the colour is developed.
-- KiwiJohn, Dec 28 2003

Good Idea. Here is a vomit green => golden brown croissant. <spacecadet goes into hyper little happy blurb> By the way, I have color-changing nail polish! It's plummy when I'm cool, red when I'm warm, and it comes in a cute bottle that looks like a lightbulb!!! </spacecadet goes into hyper little happy blurb>

Yes, I am easily amused.
-- spacecadet, Dec 28 2003

Deep breath - anger of Dec 27 faded now.

[spacecadet] I think it might have been your nail polish on the wall under the layers of paper - it changed colour under the heat gun too.

And [KiwiJohn] I think the 4-day drying time might be a problem. I want a paint that behaves like modern water-based synthetic products - quick drying and odourless - but with a colour that changes over a period of a couple of hours. I looked in B&Q, but it seems they try to make paints look the same colour wet and dry these days.
-- suctionpad, Dec 29 2003

There’s a spackling compound that goes from pink to white, to let you know when it’s dry. And it’s actually rare for a paint to dry to exactly the same color, due to factors like gloss and so forth.
-- ldischler, Dec 29 2003

Pretty good.
-- DesertFox, May 07 2004

Here in England they actually make paint that does this. Dulux Magic White: It goes on pink and dries Brilliant white (see link)
-- UndeadWario, Jul 21 2004

yeah, it's baked now.
-- neilp, Feb 27 2006

random, halfbakery