If you have a lot of posters, displaying them can cost a small fortune. All acid free materials should be used. Never use Glass. Glass can stick to the face of the poster over time. Never use regular cardboard for backing as it is very acidic and will stain/yellow a poster over time.
The following is a cheap, safe way to frame your posters and they are easy to remove and replace with others as desired. This is the method we used in our old showroom.
Buy foam core and Plexiglas, these should be available at a wholesale plastics or framing supplier. Be sure to ask for acid free foam core.
They come in 4′ x 8′ sheets. Foam core is about $12.00/sheet. It comes in black and white, but black looks really good if you plan on leaving borders. Buy non glare Plexiglas one sixteenth of an inch thick for about $45.00/sheet. UV filtered sheets cost quite a bit more ($80.00 to $100.00). If your poster is valuable, don’t skimp! Get the UV filtered!
Cut foam core and plastic about 2 to 3 inches larger than the poster on all sides. The plastic supplier should be able to cut the plastic for you for a nominal price.
You can frame 3 one sheets from a 4′ x 8′ sheet of Plexiglas.
Use small office paper binder clips to hold it all together. This works surprisingly well! You can remove the steel handles from the clips after you put them on for a much cleaner look.
Now, how do you hang it? On the top border in the middle about 1 inch from the top of the Plexiglas, mount on the back a picture hanger. You will have to drill through the Plexiglas and foam core 2 small holes to do this. You can buy the picture hanger at Home Depot and mount it to the back with tiny screws you will also have to buy.
To frame a one sheet costs less than $20.00. If you use UV filtered Plexiglas it costs about $35.00. It is well protected and the poster will not slide/move at all. It is very light weight and sturdy enough to hang. I’ve done all sizes including 3 sheets and French One Panels and they look fantastic!