it would look very suspicious if you had a bunch of blank pages everywhere

Very cool instructions indeed,however i have tried it but the result were not good wit red uv ink. My solution was to purchase red uv invisible ink for printers from uvstuff.com and fill my own cartridge.For those interested above you can print any color in invisible using the main 4 color uv inks with a printer cartridges .Only by mixing those colors you will be able to print all others.

You could also use lemon juice or milk

You don't need to buy all those invivible ink pens to get the invisible ink. There is a brand of fountain pen ink called Noodler's Ink, which sells invisible UV ink, avalible from many online distributors.

 Will it ruin the insides of the ink-jets? I was thinking about using 2 different black cartridges 

How do you know when you run out of invisible ink

oh i forgot to say over a candle!?!?

awesome instuctable..also you can use lemon juice and when you want to see it hold i about 3-7 inches away from the flame. make sure the paper doesnt burn though..

oo great idea, but you also wouldnt be able to print in any other colors besides the primary colors other than yellow because the printer mixes the colors to form other colors. it would just be easier to replace the black ink and only print in black.

very good videography! and song selection....sounds like a cool trick..

Wow! Just hope no one tries to use the seemingly blank paper afterwards =]

where can i buy invisible ink pens?

Dos formulas para tintas invisibles: 1.-Sulfato de Quinina disuelto en agua destilada. 2.-Fluoresceina Sodica disuelta en etanol. Two formulas for invisible ink: 1.-Quinine Sulfate dissolved in distilled water. 2.-Fluorescein Sodium dissolved in ethanol.

Does this work for all ink cartridge?

genius.

this would be a cool project, unfortunately ink cartridges are so expensive... it cost as much money buying ink cartridges as putting gas in the car

PRINTER UV INKS RECIPE

VISIBLE YELLOW

• Fluoroscein Disolved in water
• Acridine Orange Disolved in Ethanol
  

VISIBLE RED

• Rodamine Disolved in Water
  

VISIBLE BLUE

• Not Ready
  

INVISIBLE YELLOW

• Zinc Sulfide doped with Cadmium Sulfide (Doped with microwaves)
  

INVISIBLE RED

• Zinc Sulfide doped with Manganese Sulfide (Doped with microwaves)
  

INVISIBLE BLUE
*Zinc Sulfide doped with Silver Sulfide (Doped with microwaves)
*Naphthalene disolved in Cyclohexane
*Aminomethylocoumarin Disolved in DMSO (Dimethylosulfoxide)

INVISIBLE GREEN

• Acridine Disolved in water with a few dropets of Sulphuric Acid

  ---

Please inform me about new methods.

Nice inst - why cant I rate it ?

Very interesting.

good one. that will actually be better than just drawing with the invisible pens, since they may leave indentations in the paper.

Excellent!

I think this is just about the coolest Instructable I have seen so far. Awesome. How hard is it to take out the ink from the pens, do you have some sort of technique?

Cool! might try this on an old inkjet I have.

That is genius! I think I would try it with a black in cartridge to save the work of changing the text color. I might try this if I get a spare printer.

Wow! Very Cool! Great Instructable!!!