DIY Homemade Photo Emulsion For Screen Printing

Transfer your t-shirt design on your screen during the photo emulsion step.

Creating you own t-shirt and poster designs and then printing them at home is an easy way to showcase your talents and save money from having to outsource the impression process. Screen printing is an economical way to put your designs on almost any fabric or paper. One of the crucial steps in screen printing is photo emulsion. Photo emulsion is a substance that reacts to ultraviolet light to transfer your design onto the screen.

Things You'll Need

• Design Copy on Transparent Sheets
• Screen
• Flat Piece of Glass
• 150 Watt Light
• Potassium Dichromate
• Water
• Elmer's School Glue
• Bowl
• Empty Plastic Bottle
• Squeegee

Instructions

1. Mix the potassium dichromate with warm water at a ratio of 10 portions of water for every portion of potassium dichromate in the bowl. This is equivalent to mixing a tablespoon of potassium dichromate with one ounce of water. The potassium dichromate should dissolve completely into the water. If it doesn't, add a little bit of water until it does. You can mix the solution, but do not shake it too hard.

2. Add 6 ounces Elmer's school glue water to the dissolved potassium dichromate. This will help the solution stick to your screen. Mix the solution until it is thickens.

3. Pour your solution into an empty plastic bottle to make it easier to use. Travel bottles are good for this.

4. Spread the solution onto your screen with the squeegee to make it even. Let the solution dry completely. You can use a fan to speed up the process, but do not use a heat source such as a hairdryer.

5. Place the transparent image on the dry screen and then use a piece of glass to hold it in place.

6. Use the 150 watt light and let the image sit for about 10 to 20 minutes with direct contact with the light. The solution will harden where it should stay in place, and will darken on the parts that will later on be washed out.

7. Bring your screen to a sink and rinse the solution in water. Everything that had turned black will be washed away, leaving only what you need on for your design. Use a handheld shower head if you have one as a bathtub is big enough for most screens. Use lukewarm water to make sure you do not wash away all the solution.

Tips & Warnings

• Identify the bottle in which you keep your leftover dichromate solution to indicate toxicity. With a non-erasable marker draw a skull head and write "danger" in bold letters. The photo-emulsion liquid resembles juice and can be attractive to children, so it is important to keep of out reach, out of sight and clearly marked as toxic.

• Keep the solution out of the light for up to a year. Use it as long as you see no changes to its quality or texture. If it appears slightly more saturated than it should, simply add water.

• Potassium dichromate is a substance dangerous to your health. Do not inhale or let it touch your skin. Use gloves while handling.

References

• Silkscreen Tutorials: Screen Printing Equipment Basic Materials
• Die Hippie Die: A DIY Guide to Screen Printing T-Shirts for Cheap
• Bill Mabrey: Mixing Dichromate Solution