Modern luminous powders based on rare earth doped strontium aluminate have transformed glow in the dark applications. They are available in a number of colours but the green one appears to be the brightest and will outshine and outlast zinc sulphide/copper formulations by a factor of ten. Many products that use luminous formulations such as clocks often disappoint the purchaser as they simply do not last the night. The use of this recent technology really does get over this problem.
One factor does make their application slightly difficult in that they are a little coarse in size making it difficult to hold the material in suspension in a liquid medium for easy painting and it might be more informative to describe the material as 'glow in the dark crystals'. You cannot take the obvious step of grinding the material because the performance is heavily dependant on the crystal structure and grinding has a negative effect.This may be a factor in the performance of luminous paints and sprays that have been used in many projects.
This Instructable shows a way around the problem, at least for the small areas involved in the production of stickers. We paint/drip a lake of nail varnish on the sticker and then apply an excess of 'glow in the dark' powder on the top. The nail varnish then mops up the powder until it forms a cake. When the nail varnish is dry we are left with a solid 'cushion' of 'glow in the dark' powder and dry nail varnish. A final coat of nail varnish then stabilises the structure.
Cheap nail varnish turns out to be a superb medium for this application and it allows the rare earth doped strontium aluminate to perform optimally--the products shown in this article really will, when activated, glow right through the night.
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Step 1: You Will Need
You will need:
(See the pictures above.)
Shown in the first picture is 'Glow in the Dark Powder'. Easily available from EBay. These powders are based on strontium aluminate doped with a rare earth and far outshine the old zinc sulphide types. I prefer the bright green variety as this is brightest and shines for the longest after activation.
Also in the first picture we see clear nail varnish. Choose the very cheapest; we obtained ours from the local 'pound' store. More expensive ones may contain components that can absorb the short wavelength light that we need for activation.
The first picture above also shows a selection of sticky pads of the type used to place under furniture legs to prevent scratching, they are fibrous material with a glue backing and mounted on waxed paper from which they are peeled for use. The small pads are the ones that are of immediate use as they have a smooth surface but the larger pads and the sheet have a fibrous surface akin to blotting paper and these will require special treatment to prevent them from absorbing a large volume of nail varnish. For simple small stickers the second picture shows the smallest pads extracted from the bag and these will be used initially.
The third picture above shows another possibility. Here we have double sided sticky pads three-quarters of an inch square. They are mounted on an uncut paper backing sheet and also have a top paper sheet cut into the squares along with the pads.
The fourth picture shows sheet magnetic material with a sticky backing applied to one side. This material is much used in modern fridge magnets. The material was obtained from a local craft shop.
Step 2: Prepare Your Pads
The method of applying the powder to the substrates is the same for all of our base material types so they are shown going through the procedure together.
On the left in the picture above we see four of the smallest anti-scratch pads then next on the right is a square of double sided sticky pad with the protective paper removed and lastly there are two cut squares of the magnetic sheet. The top magnetic square is smooth side up and the sticky side is underneath with the paper protection still in place. The bottom one is sticky side up with the protective paper removed.
Next on the right we see a wooden cocktail stick and lastly the two protective paper squares that were removed.
The wooden cocktail stick is useful when manoeuvring the squares into position especially during the next step.
Step 3: Applying the Glow in the Dark Powder
Now the most important part and this does require some practice and patience. Using the brush that comes with the nail varnish (or something more superior if you prefer,) apply nail varnish to the surface of the sticker. You may find that it helps to wet the whole surface first with a lightly loaded brush and then drip/apply as much nail varnish as you can without it flowing over the edge--you should end up with a substantial lake of varnish on the surface.
Working quickly, because the nail varnish will dry rapidly, spoon an excess of 'glow in the dark' powder on to the lake of nail varnish. The result is shown in the picture above. Now allow to dry for several hours or overnight.
Step 4: Shake Off the Excess Powder
Gently tap the stickers on to sheet of paper, extricate the stickers and return them to the work surface. Gather up the excess 'glow in the dark' powder for future use.
If you have gaps or uneven areas in your work especially around the edge you can repeat the previous step with more nail varnish and powder. See the results above.
Large areas may be a little uneven but this does not affect the luminous properties.
Step 5: Finish Off
We now consolidate our work by applying a final coat of nail varnish and leave to dry, This yields a fairly robust surface although it will not withstand a determined attack with finger nails or an implement.
Step 6: A Successful Application and Other Suggestions
There are an enormous number of potential applications--anything that a sticker will adhere to and that you want to find in the dark, light switches being an obvious one. Travelling alarm clocks often have a press switch that activates a light for a few seconds but one of these stickers will help you to find it first. If you are using this in a dark place which does not receive much daylight then you can 'charge up' the 'glow in the dark' material by holding it near a light bulb or applying a torch for a very few seconds. The resulting glow will now last for the night.
On the left of the composite picture shown above you can see what must be one of the earliest commercial LED torches--just a couple of white LED's driven by a pair of lithium cells. This still does good service as our travel torch and has illuminated our nocturnal perambulations in many dark hotel rooms. The problem comes when trying to locate the torch in darkness and in doing so it is easy to make a noise whilst groping for it or even knock it on to the floor resulting in an awoken partner and commensurate loss of household credit. Problem solved! A small 'glow in the dark' pad has been affixed to the torch and held against a light for a few seconds resulting in a glow that will last the night allowing for immediate location of the torch. The right hand side of the picture shows a picture taken in darkness after the pad received a very few seconds activation with a separate torch.
Step 7: How to Make Sticker Shapes and Magnets
When I first started developing this project I anticipated that I would use the large circles or make shapes cut from the sheet in the selection of anti-scratch stickers shown at the beginning. Unfortunately the material used for the larger stickers is very absorbent and would need huge quantities of nail varnish. I did have some success with first sealing the surface with emulsion paint but as the project progressed it became apparent that the magnetic sheet is far superior and much more versatile and hence the rest of this project goes down that route.
If you want sticky shapes than just apply the 'glow in the dark' powder to the shiny magnetic side and then peel the backing to expose the sticky surface.
If you want to make a magnetic shape then peel the backing and apply the 'glow in the dark' powder to the sticky surface.
If you want a two-sided shape then it is possible to apply 'glow in the dark' powder to both sides in succession resulting in a two dimensional item that can be used in mobiles.
In this example the shape became a magnet.
First we need a template for our shape. In the first picture above on the right we see an image of a cat gleaned from the internet that has been printed out on white paper and cut down to size alongside a piece of magnetic sheet cut to be just larger than the paper image.
The second picture shows the paper attached to the piece of sheet magnet by gluing around the periphery with a water based glue.
The third picture shows the shape which has been deftly cut out with scissors. This is craft work and other constructors will have their own ideas and equipment for this part of the job.
Lastly, glow in the dark powder was applied in the manner shown in Steps 1 to 5 and the fourth picture is a composite showing resulting cat shape in the light and in the dark after activation.
Step 8: Some Further Ideas--1
The technique shown will work for any surface that will accept basic nail varnish which, at its simplest, is a solution of cellulose nitrate in a solvent such as amyl acetate possibly thinned with acetone. This is an aggressive solvent for some plastics so be careful. Bearing that in mind, many existing items such as fridge magnets can be made to glow in the dark. Notoriously, some clocks have luminous properties that disappoint in that the luminosity does not last the night and the technique shown will allow rectification of this if you can get at the clock face--simply plant small stickers at the hour points and nail varnish/powder to the hands.
Within reason there is no obvious limitation on the size of any item given the 'treatment' and it may be that a fairly large item could serve as a child's night light whereby it could be activated with a torch at bedtime and provide a fairly bright light initially but then become progressively dimmer as the sandman does his good work.
There is potential for making Christmas presents and also items for sale to raise funds on a bazaar stall.
Step 9: Some Further Ideas--2
The ideas keep on coming!
A glass surface is perfect for the technique and hence we can decorate mirrors and picture frames. It takes a little more care but it is possible to lay a shaped pool of nail varnish on to the glass surface using a fine brush and/or a wooden cocktail stick followed quickly by some 'glow in the dark' powder. After drying and shaking off the excess powder followed by the application of a consolidating coat of nail varnish the job is done.
In the pictures above we see a cheap picture/photo frame that has a glass panel. Behind the glass is a sheet of black cardboard and on top of the glass is a shape prepared as in previous steps, (sorry yet another cat,) and also some astronomical detail laid down, mainly with a cocktail stick, as per the previous paragraph. Some artistic license was deployed as a crescent moon will never appear in the same constellation as the Plough!