How To Print Posters
If you are currently operating a shop that caters to younger groups of people, adding screen printed poster printing capabilities could add a great revenue stream with minimal investment.
What is Screen Print Poster Printing?
Screen printed posters have become very popular products for bands selling merchandise, art galleries selling premium but low cost products, and so on. For people (like me) who have way too many t-shirts, or who want a souvenir to last longer than a garment, posters are a great option. And for printing shops, this can open a lot of doors.
How is Poster Printing Different from Textile Printing?
In some ways, poster printing is easier than textile printing. Inks are air-dry, so you don’t need to worry about proper cure. You also print one color, let it dry, and print the next – so you don’t need to have large, space-consuming equipment. Just a one color press with a vacuum table is all you need.
You are printing on a super-flat, non-textured surface, so you don’t have to worry about how the ink’s going to lay down, and you can use very high mesh screens.
As always, I like to talk about the margins you can make on posters. Paper is exceptionally inexpensive, ink usage is minimal, you don’t need to run your dryer to cure the posters, and so on. For a one-color 12.5×19 poster, which costs $0.23/sheet from French Paper, companies are charging about $3.50/poster, charging $1.50-$2.00 for each additional color. The total cost for a one color poster is about $0.50.
What do I need?
For equipment, all you’re going to need is a one-color press and a vacuum table. Some people even make their own vacuum tables with a shop vac and just use hinge clamps to hold the screen.
- High Mesh Screens – We recommend 230 or 305 mesh screens, but you don’t want to go below 200. Use a screen larger than your design; if you’re printing a 12.5”x19” design, use a 23”x31” screen.
- Water-Resistant Emulsion – Chromaline CP-TEX or UDC-ACE
- Squeegee – we recommend a 70 durometer or harder squeegee
- Ink – Permaprint Premium is a water-based, air-dry ink for poster printing, which has great coverage and can be reduced down with a little bit of water for better printability and to stretch the life of the bucket of ink.
- Paper. We’ve gotten ours from French Paper, who manufactures a variety of colors and sizes of papers that will work well for any application. Ultimately, all you need is a good cover stock or cardstock paper to prevent warping. One benefit of ordering from French is that they have a library of retro images that you can use when printed on their products!
- Paper towels and a spray bottle filled with water
How do I do it?
Before you Print
So you’ve got your supplies all ready, press is set up, design is prepared. First step is you’re going to expose your screen with the design on it. Be sure you are properly exposing your screen! An underexposed screen can cause early breakdown of your emulsion.
Next you’re going to set it up on your press. One nice thing about poster printing is that you don’t need to worry about having the screen totally straight and all that. All you’ll do is line up your screen to a sheet of paper, and then tape down three business cards or cardstock paper to butt up your paper against. You just made a three-point registration system. You’re going to want very little off contact on between your screen and your paper.
Be sure everything is laid out properly before you pull out your ink. One thing I like to do as I’m setting up is to spritz the screen with some water to pre-wet it – this prevents your inks closing in too fast. Once you’ve put ink in the screen, it’s a race against the clock to ensure your ink doesn’t close in – especially if you’re in a dry environment. So have a spray bottle, some paper towels, more ink, and all your paper close at hand.
If you want to reduce your ink, you can do this now as well. Permaset says you can reduce your ink with up to 3% water to improve open time. If you want to reduce opacity, you can use extender.
So now you’re ready to print.
Right before you start printing, wipe down the screen so there isn’t any pooling water on it. Lay down your paper and butt it up against your three registration holders, turn on the vacuum, load up the screen with ink, and print. Immediately flood the screen when it’s done printing and look at the design. Make sure it’s lined up on the paper – if it didn’t completely cover the print, that’s fine, just check to make sure it does it on the next. Work as quickly as possible and keep an eye out for portions of the screen closing in.
You don’t need to print with much pressure at all to get a good result. Just enough to push the ink through – practically the weight of the squeegee doing all the work.
If your print starts closing in, don’t worry. Just do a print and don’t flood the screen, spray a paper towel with water till it’s damp, and wipe down the back side of your screen. I’ve learned that if one section is closing in, you’ll still want to clean the whole screen – the rest of the screen will start trying to close in as you’re cleaning it. Once you’ve cleaned the whole screen, take a dry paper towel and wipe it down.
If you get a lot of ink going where it shouldn’t be, you might have over-flooded or printed with too much pressure. Try hard-flooding the screen so that the ink gets down into the open mesh, instead of pooling on top and around the design. If you have scrap paper, the easiest way to clear this out is to just print a few times and keep working.
When You’re Done
Once you’re done printing, take the screen and scrape out the remaining ink. Wash off the excess ink and make sure you don’t have any buildup. Save the screen in case you have to reprint the color.
The process for doing more colors is essentially the same as the first, except you will line up your screens off of the first design. When you’re first starting out with poster printing, print more than you need to make sure you don’t have to redo a portion of the job.