How to Make Electroluminescent (EL) Paint!!

I first came across EL Paint when researching how to make my own EL Panels. Lighting is something I really love and the applications for this type of lighting are endless!

This is my first instructable, it's also very long - so apologies for that.

****I must warn everyone of the following before you begin****

- Ensure you read ALL safety directions and the MSDS (Material Safety Data Sheet) for each chemical prior to using it,

- This project deals with high voltage AC, it's very easy to electrocute yourself if you do not seal the circuits prior to applying power!

- Ensure you use all PPE (Personal Protective Equipment) when handling the paints and chemicals, and

- Store all chemicals in a safe place, away from children.

Before you begin, have these things handy:

1. Nitrile Gloves: They can be expensive, but are resistant to a fair amount of chemicals.

2. Particulate Mask: You need these!!! (or equivalent) - the powders in this project can be super fine ~10nm or smaller.

3. Eye protection

4. Emergency eye wash.

Please use this equipment!

This project is also VERY EXPENSIVE to get started. Fair warning ;)

This is a (non-exhaustive) list of basic equipment you will need:Prices are in $AUD

1. Heat Gun ~$60

2. Multimeter ~$10

3. Rotary Tool with stirring attachement (or something that can stir smal amounts of paint) - I used a rotary tool with milk frothing attachment ~$100

4. Paint Brushes x 5 smal to medium size. One for each type of additive plus spares ~$20

5. DC to AC Inverter - This is what drives your paint. These are cheap and come in many varieties and power outputs. I suggest using the battery power type while you get started - it's cheaper! ~$5

6. UV Blacklight - To see where you apply the phosphor layer ~$15

7. Glass jars (or equivalent) These are to store the paint once mixed with the additives. Any container with an airtight lid will work. ~$10

This is a list of the paint additives you will need - All ingredients can be substituted to suit your locations and suppliers, EXCEPT where it states "cannot be substituted" - this means that type of ingredient must be used.

1. Any clear coat polyurethane paint (water based is best). Must be a single stage/pack type of paint. Wood varnish is easiest to work with while starting out. ALL of your additives will be mixed with this paint. ~$50

2. Electroluminescent Phosphor - CANNOT BE SUBSTITUTED It costs ~$300/kg (this is true only for unecapsulated phoshpor, which is the cheapest). Do not confuse this with photoluminescent phosphor, that's glow-in-the dark powder and will not work.

3. Baruim Titanate (BaTiO3) CANNOT BE SUBSTITUTED - This is the Dielectric additive. It costs ~$80 for 250g.

4. a. Copper Paste/Paint - Cheapest and highly conductive, but messy and uneven to work with. Not transparent enought for the top layer, use for the base layer only. ~$70

b. PEDOT:PSS - Very expensive. Electrically conductive and transparent when applied properly. ~$700/kg

c. Silver Nano-Wires - Very expensive. Electrically conductive and transparent when applied properly. ~$990/kg

d. Double sided copper tape - Excellent for the base layer, cannot be used for the top layer. The glue can react porrly with the PEDOT:PSS though.

e. Any other conductive substrate for the base layer - such as aluminium sheeting (that can be sealed).

** This instructable will only show you how to make your first EL Lamp on paper with a paint brush. Air Brushing/Spray painting and applying this to various substrates such as cars, textiles and wood are more complicated and will not be covered**

The 'functional' EL paint is made up from 5 seperate layers of paint with different additives dispersed within. The layers work together to produce light via electroluminescence. (This is a really basic description).

The layers are comprised of the following (from base to top coat):

1. Electrically conductive base layer

2. Dielectric layer

3. Phosphor Layer (electroluminescent)

4. Electrically conductive clear layer

5. Bus Bar

Using this basic construction, this system can be applied to anything from a car to your bedroom walls!

All-in-all, the EL paint comprises a number of layers to achieve luminescence. The following directions outline the components and manufacture of each layerfor a simple, single layer, single sided EL Paint application.

All steps from here are written using the following electrically conductive products:

PEDOT:PSS

Copper Paste

Copper Tape

The base coat conductive layer is applied to the desired substrate - in this case, paper. I use the copper tape or paint to as my base layer.

1. Apply a thin, conformal coating of you electrically conductive paint or a layer of your copper tape, as shown in the picture, to the paper. *note: thickness should be no more than 1mm - (if the copper paint is not conformal, it will 'arc' electricity between the ridges in the paint and short circuit your lamp. The ridges also make it harder to insulate the base layer). If you use copper tape, make sure you smooth it out if needed.

2. This base layer should normally form the rough outline of your EL lit field (the area that lights up). You will need to extend a 'tail' out from the square you just painted - this is where the inverter will connect to the base layer.

The following is only applicable if you chose paint as your base layer - not copper tape.

3. Use your heat gun to gently dry the base layer and allow to cool.

** Ensure you don;t over heat the paint or it will boil and cracks will form. This breaks to continuity of the base layer, resulting in only partial illumination.**

4. Test the resistance of the base layer using your multimeter. You need to achieve a resitance of less than 1ohm over the entire area. The lamp may still work if the reistance is higher, however the light will not be even across the entire area. this is because as the voltage drops, so does the light.

Now we need to insulate the base layer from the phosphor layer and top electrode.

BaTiO3 to Varnish ratio is 19.1g of BaTio3 : 80.9g of Varnish

1. Check the base layer is dry...(if you used the paint)

2. Apply a thin coat of the Dielectric paint over the base layer.

3. Ensure that the Dielectric paint extends out, over the edges of the base layer. This ensures it is fully insulated.

4. Do not paint over the 'tail', this needs to have the inverter connected to it.

5. Use your heat gun to gently dry this layer and allow to cool. ** Ensure you don't over heat the paint or cracks will form and it will short circuit the base layer to the phosphor and top electrode layers**

6. Connect your multimeter to the 'tail' and then to the insulated area of the lamp. You should not get a reading - because we insulated it ;)

This is the fun part ;)

EL Phosphor to Varnish Ratio is 30g of Phosphor : 70g Varnish

1. Prior to applying the layer, you need to re-disperse the EL Phosphor into the varnish. It would have settled quite quickly to the bottom of your container. Use the rotary tool and the UV light to mix and check the dispersion as you go.

2. Check the Dielectric layer is dry....

3. Once suitable dispersed, brush the EL layer onto the Dielectric Layer.

4. Use the UV light to check you achieve an even dispersion across the lit field.

5. Use your heat gun to gently dry this layer and allow to cool. ** Ensure you don't over heat the paint or cracks will form and it will short circuit the base layer to the phosphor and top electrode layers**

Now we apply the top electrode layer. I used the PEDOT:PSS for this as it's transparent and conductive.

1. Ensure the EL layer is dry...

2. Apply the top electrode. Ensure you don't paint over the exposed base electrode layer!! or you will short circuit the panel.

3. Wait until this layer is completely dry before moving onto the next part. I suggest not using the heat gun for PEDOT:PSS. Let it air dry.

The bus bar ensures an even application of electricity around the whole of the lamp.

Make sure the bus bar is applied so that it touches the PEDOT:PSS - It will also help to place an additional layer of PEDOT:PSS over the bus bar.

Let the paint dry completely for a while then apply power to your two exposed electrodes.