Recently, after weeks upon weeks of investigation (like 5 weeks maybe) ive at last solved a huge personal problem.
I sell thermochromic pigments (and other special effects pigments, materials, ect ), and with so much, so cheaply at my disposal, i also like to envision many projects i can do on a whim, not like a few years ago when one had to carefully plan everything out and make the best use of their $2+/g pigment from the other online merchants.....
Any-who, this problem was the complete lack of plain acrylic paint medium, that is, acrylic paint, without the color, and i don't mean white paint, im talking about pigment-less paint.
Manufacturers rarely make blank mediums and when they do its overpriced and often full of so many additives its not suitable to mix with pigments or dyes because it needs to be diluted with actual paint. In short, not the best stuff for mixing paint with. it works, but plain and pure in this case is always better.
Then it came to me! Why not filter out the pigments!
A dumb idea at first, the ideal paint to filter is titanium white paint since any expected leakage of color wouldnt make much of a tint, problem is you'd need a centrifuge and a micro-nanometer filter or a dilutant you can safely remove from your paint after without causing it to set, making it thin enough to pass through filter paper. Its impossible, not without exceeding the costs of buying actual pure medium which is always premium stuff costing like $50 for 250ml.
Since normal paint is out of the question, there is an alternative!
glitter! the "pigment" in glitter paint isn't >300um talcum stuff, its <1mm particles, easily filtered with a broad filter.
I found out its possible to attain a clear, pure colorless medium, by filtering glitter paint.
There is just one hitch, it requires a fair amount of pressure, it likely wont filter under its own gravitational pressure.
This hitch is circumvented though by following the instructions on the next page
Step 1: Materials
OK, before you can start your going to need the necessary materials. Though its not exactly rocket science, most anyone can do it.
- Glitter or particle paint in a CLEAR suspension
- a clear or white glass/cup with a capacity of at least 3/4 of the glitter paint Or a suitable bottle for permanent storage
- thin but fine threaded fabric
The fabric must be thin and consistent, i used a rag which was previously a pillow case.
The fabric must be consistent enough not to allow any glitter through and strong enough that you can apply a decent amount of pressure.
As for the container your going to place the clean medium in, make sure its at least 3/4 of the volume of paint your using if not equal. its unlikely you'll get more than 80% of the medium out before the glitter concentration becomes to high.
Step 2: Doing Stuff With the Thing
First things first you gotta prep the glittery goop. Ideally buy one which has been sitting still for a long time, and has had all the glitter settle, or otherwise, let your glitter sit a few days completely still. it will make the process impossibly efficient.
Using the aforementioned scissors on the appropriate fabric, cut a large square of fabric, big enough it will surpass the threading of the bottle, that's the minimum requirement, easily met.
next, wet the square or else things will get tricky and messy, remove the cap, place the square on the bottle and screw the lid back on.
Step 3: Squeeze!
Get your container ready, bottle or cup. I recommend using your final container you intend to permanently store the medium in, or a cup if your going to mix pigment in straight away.
You need to make sure you move the medium between containers as few times as possible, because in a 250ml cup you can be sure that about 10-30ml is going to stay stuck to the container if you try to pour it out.
If possible, wait until the glitter settles or keep it settled if that's how you bought it.
start squeezing that goo out.
It will come out clear hopefully, the glitter getting blocked out.
For the first half try to squeeze out as much as possible before it all clogs up. After the first half of volume is squeezed out it will get harder, but you'll be able to keep going until you've moved about 3/4-4/5ths of the liquid out.
Towards the end you need to start shaking it up and unsettling the glitter so it doesn't block the fabric, but at no point will it ever become impossible that much i can assure you, just harder.
Of this i managed to get 200ml out of 250ml out before giving up. Still, given that's 200ml which i paid $7 for, compared to $15 for 175ml, im quite happy and you ought to be too!
Step 4: Using Your New Medium
I found out immediately one of the key benefits of this pure acrylic polymer ( as its referred to in this state ), when mixing it into thermochromic pigment, a light fluffy and hydrophobic pigment (repells water like oil), this stuff, unlike normal gloss or matte mediums requires no machine mixing, it took in the pigment as if it were a polar solvent that "wets" the powder instead of just slowly blending in and gradually forming a suspension.
of course it didn't literally do this, but it was faster than ive ever seen it happen
In the second photo note how black the paint mixture is, this happened with only a little bit of hand mixing. again otherwise improbable with purpose built medium.
Before packing it away to test if anything in the paint would have an impact on the sensitive thermochromic pigments storage life, i did a test paint and as you'd expect the effect was AMAZING! it automatically set itself at the exact correct thickness required for the thermochromic effect, not too thin that you can see through it and not too thick that whats underneath is blocked out by the semi opaque particles or that body temps have difficult completely transferring enough heat to activate the pigment.
in short this pure acrylic polymer is the best stuff ive ever dealt with, itl probably handle the super heavy glow powders well too!
Anyway, this concludes my instructable.
I hope it helps!