Paste Paper Patterning on Plastic Bags

by Beki Ries-Montgomery

Don’t you just love it when play and experimentation with materials pays off? That’s what happened to me. I was trying to learn how to fuse plastic shopping bags into a firm, stitchable fabric and it was behaving more like Tyvek. It wanted to bubble and shrink. So I thought paint on Tyvek does really cool things when it shrinks and bubbles, let’s see what happens when I paint the shopping bags before ironing. Turns out that the paint appears to act a bit like a resist and lessens the bubbling and buckling. Good to know, but not terribly interesting. I’d used fluid acrylic paint, and I noticed that straight from the bottle, it was thick enough to retain the imprint of blunt-tipped tools drawn through the paint. Hey, this looks like paste paper markings! What follows are the steps I take to make paste paper patterns on plastic bags. Like any nascent technique it is unpredictable and rife with uncertainties. The most unpredictable aspect that I’ve encountered is the fusing together of multiple plastic bags. There appears to be variation in the physical properties of bags from different sources that affects how they react to heat. I don’t always end with a wrinkle-free sheet. So keep an open mind and good notes and enjoy the journey.

Let’s begin.

Materials

  • Fluid acrylic paints
  • White plastic shopping bags
  • Masking tape / painter’s tape (low tack)
  • Foam brush
  • Patterning tools

Note: Unlike traditional paste paper, the tools used to mark in acrylic paint need to be flat to scrape away paint to reveal the underlying plastic. Pointed tools, like combs, do not displace enough paint to leave a mark. The blunt sides of patterning combs, available in the paint department of a hardware store, work well. I like notching and using plastic cards; expired gift cards or the fake credit cards that come in junk mail. Because I notch them myself, I have a great deal of flexibility by varying the width and spacing of the notches.

Materials

Notched Plastic Cards

Patterning on Plastic

Note: Acrylic paints dry relatively quickly. Read all the directions and have all your supplies gathered before you begin this project.

1. Remove handles and bottom seam from one ordinary white plastic shopping bag.

Cutting away handles and seam

2. Reverse pleats, if any, smooth out wrinkles, and flatten bag, print side down, onto work surface. Tape down all 4 edges, pulling slightly to create a taut surface. If you work with the printing face up some of that printing will be visible after you scrape away the paint.

Bag taped down and squirted with paint

3. Squirt 4-5 squiggles of paint across the surface and spread it out with a dry foam brush so that you no longer see white plastic. The layer needs to be thick enough to have some paint to scrape away and contrast with the white plastic but not so thick as to create ridges. If the paint is laid on too thickly, it may peel off of the plastic once it’s dry. Here I have used Golden fluid acrylics in quinacridone gold and crimson to achieve the rich color I wanted.

Note: I’m still learning about paint mixing. It has been my experience that dark colors easily overwhelm the lighter ones.

An idea of how thickly to layer the paint

4. Using the notched plastic card, begin at one corner of the plastic and drag it through the paint along the surface of the plastic bag making a set of horizontal lines.

2 passes with notched card

5. Move to the next area and repeat. Repeat this step until the entire surface is covered with parallel horizontal lines.

Horizontal lines across entire surface

6. Beginning at one corner, draw the card through the paint creating vertical lines.

Vertical lines crossing over layer of horizontal lines

You’ll see that as the notches cross over the existing white lines the displaced paint breaks up the lines into a series of white dashes. Repeat until the surface is covered with vertical lines.

Layer of vertical lines completed

7. Remove tape and set aside to dry overnight.

Fun Options: In making these line patterns you are not limited to two layers of lines. Nor must the lines be straight or even parallel. I especially like playing with curved lines. Google “paste paper” for inspiration on all sorts of mark making. “The Art of Making Paste Papers” by Diane Mauer-Mathison is also a good reference.

Curvy lines in one and two layers

Diagonal over vertical lines

Fusing Plastic Layers into a Durable Sheet

Note: Read through these directions thoroughly before you begin. Before fusing your first sheet of patterned plastic, you might consider practicing with a painted but un-patterned bag to get a feel for the process.

1. Preheat iron between the Silk and Wool settings.

2. Cover the ironing board with a sheet of baking parchment larger than the plastic bags.

3. Remove the handles and seams from 3-4 plastic shopping bags.

4. Flatten, smooth, and layer these bags onto the parchment paper on ironing board.

5. Place painted sheet, paint side up, on top of this stack.

Bags layered between sheets of parchment paper

6. Cover the entire stack with another sheet of parchment paper.

7. Taking your time, press the iron over the parchment paper fusing the plastic layers underneath. Hold the iron for a few seconds on each spot then move on to the next. Check frequently to see how fusing is progressing. It’s easier to add more heat than it is to go back once too much heat has been applied. An easy indication that the layers have fused is to turn over the stack. Look at the surface of the bottom sheet. Is it tightly puckered and wrinkled? Or smooth and wavy? If it’s tightly puckered, the layers are fused.

Close up of partially fused sheet

8. The more heat that you apply the greater the tendency for the plastic to wrinkle and shrink. To a certain degree the painted surface resists shrinkage. At least to the extent that the plastic doesn’t almost immediately shrink as soon as heat is applied. I wish I could provide you with instructions for reliably fusing the plastic bags but it seems I get slightly different results every time I try.

Finished, fused sheet

There you have it, all that I’ve figured out about making paste paper patterns on ordinary plastic shopping bags. Now go forth and play and see what you may discover!