Photo-emulsion Screen Printing

Sometimes you need to your message out quickly and cheaply. How do you print a ton of t-shirts and patches fast? Here's how I did it.

This Instructable covers the standard photo-emulsion screen printing process, which is great for printing text or images with fine detail...and at the end, you have your own personally-designed entirely unique prints on fabric, clothing, paper, or whatever else you can get under your screen.

The general idea: After stretching fine-mesh cloth over a wooden frame, you spread a thin layer of photosensitive emulsion on the screen and let it dry. You then take a black image on transparent or translucent surface, place it against the screen, and then expose the screen to light. The light causes the emulsion to harden and bind to the fabric. Where the light strikes the screen, the emulsion will bind, making a solid layer. Where the light is blocked (ie where your black image is placed) the emulsion remains water-soluble. After exposing the screen, you spray down the screen with water, washing off the emulsion only where your image was placed; this clear area is where ink will be pressed through the screen when you print. Finally, you lay the screen on your t-shirt, other fabric, or paper, spread ink on the inside of the screen, and press the ink through the screen. If you use textile ink, you can heat-set the ink after it dries, and it'll be permanent and washable.

There are some great Instructables up on the site already for screen printing methods, but there's always room for more. For this project, I went with a ready-made screen and images printed in black on transparencies.

Check out Screen Printing: Cheap, Dirty, and At Home for info on making your own screens and using the sun to expose your photo-emulsion.

Threadbanger has an excellent D.I.Y Screen Printing Instructable which covers making screens using old embroidery hoops and using Mod Podge to put your image on the screen.

How to Silk Screen has a good overview of the photo-emulsion process.

Step 1: Gather your materials!

What you need:
@ a screen
While I used a ready-made Speedball frame for this project, making your own screens is cheaper, and not hard to do. Take a look here and here for great tips on making screens.
@ a printing squeegee or piece of cardboard with a smooth, straight edge

@ photo emulsion and sensitizer
I used Speedball diazo photo emulsion and diazo sensitizer; the exposure times I list later in this Instructable are for this formula. If you use another type of photo emulsion, be sure to read the directions and test to make sure you have the correct exposure times.
@ screen filler fluid (again, I'm using the standard Speedball stuff)
@ photo emulsion remover (for taking the emulsion off the screen so it can be reused)
@ screen printing ink for fabric

@ a light table
-or-
@ light bulb (at least 150W, clear incandescent), light bulb socket with reflector, clamp, and cord

Miscellaneous useful things:
@ pushpins (at least 4 per screen)
@ chopsticks, popsicle sticks, plastic spoons -- for mixing and putting emulsion & ink on the screen
@ small paint-safe cups
@ masking tape (water-resistant tape is best)
@ regular transparent tape
@ lots of newspapers (to keep everything else clean!)
@ a book or piece of thick cardboard that's slightly smaller than your screen
@ sheet of cardboard that fits inside your t-shirts (if you're printing shirts)

Comments

[Ruswendy]

Simple but very inspiring, so the process of screen printing can be done easily, thanks
http://www.belajarsablon.com

[ebrown19]

Holla,
Brilliant Instructable!

http://www.instructables.com/id/DIY-Silk-Screen-Printing-Screen-Upcycling-Recy/

I have just posted an instructable on how to make your own screen printing screen cheaply and easily!

:)

-Emily

[jcuizon]

guys can you help me how to clean my screen...and whats the problem of my work every time i exposed my design..my design destroy pls help me......i'm using 4pcs 10WHATS lamp..thank you!pls help me

[makirro]

with respect,
perhaps its a wee bit advanced for you. have you considered finger painting or potato printing ?
maybe when you're older you can try some advanced techniques.
makirro

[emihackr97]

jajajaja

[razorwinged]

hi! i just wanted to let you know that because i like this instructable so much, i have added it to my silkscreen guide... http://www.instructables.com/id/silkscreen-printing-easy-and-cheap/

thanks for sharing your ideas!

[harry balkissoon]

i want to f u and expose it on facebook and suck our cat for 20 minutes

[Gonazar]

How far does the ink stretch? How many shirts can I print with 16 oz of ink and a medium sized design? (roughly)

[Spaceman Spiff]

Could I print up a design like this on a t-shirt using this method?

[vampyredh]

if I may make a few suggestions I am a screen printer by trade and in order to save yourself lots of money on transparencies buy a can of dollar clear spray paint and do a light coat over your velum or tansparency let it completely dry the spray paint causes the black it to get solid and dark

[kpeneff]

Wow, must be really cool to do this professionally!

Maybe you could answer this for me; I'm doing a screen print in my art class, but our classes are cut down to 20 minutes this week, so I can't burn my screen AND rinse off the screen in one class period. Could I burn my screen, then come back in 20-30 minutes to rinse the screen?

[biaginn]

After I removed emulsion from the screen to expose my writing I went to transfer the text onto canvas but the ink did not come through? any suggestions?

[makirro]

yip,
just use a marker pen and write directly onto the paper, its an ancient method developed in french caves about a million years ago.
makirro (the fool)

[nattapon05]

when you do coating do you need to do in dark room ?

[makirro]

not necessarily just as long as you put it on before you go out in the cold, you'll be fine.
makirro (the fool)

[JHAPZ_22387]

Hi there!

Some friends of mine suggested to expose dried emulsion under the sun.

Is it effective?
Anyone knows how long of exposure?

Please help!

Thanks!..:-)

[makirro]

yes but not on your body, better using a good quality heavy paper.
exposure is a little like sunbathing .. it takes a little experimentation to get just the right outcome .
makirro (the fool)

[radracer]

This has been a lot of help to me.

[honeycomb]

Can you use this method to print designs which are very colorful? or will the designs made with this method always be one solid color?

[stepandknee]

you can overlay a print of one color with another, or you can just cover some areas with masking tape and print with one color, and then vice versa and print with another color

[coask8b]

is it possible to expose the screen outside on a sunny day, instead of using a light rig, like in a similar instructable?

[stepandknee]

yeah, definitely possible, but it's very dicey. there are a lot of factors that play into exposing a screen with sunlight--weather conditions, if it's cloudy or windy.

i find it easier to just use a bulb, that way i can do it any time and it's always consistent!

[stepandknee]

if you have a design that's bigger than 8.5x11, or you don't want to go through the hassle of getting something copied onto a transparency, it works just all well to do this:

take a copy of the image and cut off some of the extra white paper around it. paint the piece of paper with baby oil. let that sink in and then dab off the excess oil with a paper towel. this makes the paper translucent, which works just as well as something transparent.

you might have to bump up the exposure time a tiny bit, but not too much. (i couldn't tell you HOW much because i've never actually used transparencies when screenprinting)

[jakethink]

Just a hint for people who can't work out the exposure times.

You can put a strip of emulsion on a screen and test like you test in darkroom photography. Block most of the strip with something light proof (a bit of cardboard) but leave a couple of c.m. hanging out. Start exposing. After a couple of minutes move the cardboard back so another couple of centimeters is showing. keep doing this every minute or so, until the max time is reached. Then wash out as usual. this way you can see which time works best and you don't have to test on like twenty screens.

I hope this makes sense. and is helpful to all those having trouble

Peace

Jake 1NE. 

[stepandknee]

ugh, i wish i would've done this before doing emulsion FOUR TIMES on a 20x24 screen until it worked.. this would've been so much simpler..

[assassinazz]

I used to work at a screen printing shop and we didn't use liquid photo emulsion, we had big rolls of emulsion sheets that were stuck onto the screens with water and left to dry in a dark cupboard. I would cut the huge sheets into 12" x 14" squares which would be put in a drawer away from light, while the huge sheets were essentially a roll stuck in a big black tube (to block the light). The emulsion sheets were pretty much just a plastic sheet with emulsion on it that would stick to the screens with water and when the emulsion dried you would peel off the plastic sheet before "burning" the logo on the screen. When the "burning" was done (on a vacuum sealed light table with timer) I would "blow out" the design with a pressure sprayer, then dry the screen, tape the edges and fill any defective holes with liquid emulsion.

[acidaleh]

In junior high my shop class did silk screen printing with that kind of emulsion on plastic - only we would put our piece of emulsion plastic-side down and cut and remove the emulsion with an exacto knife. When the cutting was done we would attach the emulsion to the screen with water, let it dry over night with pressure on the screen, peel off the plastic and then print. The teacher had basically been printing that way for 25 years, with very good results.

[stepandknee]

you did silk screening in JUNIOR HIGH!? i'm jealous!

[assassinazz]

I see. Well yes I did cut the emulsion while it was still on the plastic, its the same as you have done here but we did not put pressure on it during drying off. The shop i worked at was run by an old couple in their 70's who've been doing it for nearly 40 years. I'm still really proud of that job. How many people get to say "I was a graphic designer at my first job when I was 15." lol

[m1k3y]

Neat, I'd love to have the chance to play with that kind of equipment sometime. And I'd imagine that the sheets are a whole lot easier to work with (and less hugely messy) than the liquid emulsion. Envy!

[acidaleh]

Check out Ulano products, Ulano StaSharp is a really good easy to cut film and you can get smaller pieces online, instead of the huuuge rolls haha.

[sxe-monty]

The only problem with that technique is your design is limited by your xacto skills and it was easy to mess it up, I found

[nappilyevrafter]

easy alternative:  make or find your design on the computer, then print it out onto a transparency.  twice, so you can double-up when it's being burned into the emulsion and get a better screen.

[garlic_batman]

Can you expose the screen for too long? Assuming it doesn't literally get burnt, I don't see what else would happen if it were exposed in sunlight for an hour instead of 5 mins?

[stepandknee]

the light would definitely go through the dark areas and you wouldn't be able to wash anything out whatsoever. it would just be a sheet of hard emulsion on your screen.

that's why exposure time needs to be really precise and specific.

[frenzy]

well actually if you expose it for too long the UV light will do through the dark areas too ruining your screen

[satyr2k2]

I am having an issue with blowing out my screen once it has been burned. Twice now, certain sections of the exposed emulsion are washing away along with my design. I suspected the first time that my water was too hot even though it was quite tepid. This last try I used cold water and still I had a whole section of my art simply wash away.

For the record- both screens were set to dry overnight after the emulsion was applied to the screen. Is my emulsion coat too thin? What am I doing wrong?

[stepandknee]

you might try exposing it for a little bit longer. also something that helps is to blast water on the side of the screen that your design WASN'T laying on. (the backside). if you need to you can even try scrubbing on the back side to release the emulsion. this won't damage your design at all since it's on the opposite side. good luck!

[Ruswendy]

Nice information, thanks for sharing
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[M4industries]

What is that in latin?