Bioplastic Hardground – Methyl Cellulose: Experiment 2

Researchers: Zoe Dong and Megan Ogden 
Date: 11/8/2018
Temp: 70 degrees
Humidity: cool, partly cloudy 

Using the methyl cellulose made a week earlier, on 11/1/2018, we created two new test plates. We first beveled the edges of the copper plates, applied backing sheets and then de-greased both plates, using first Bon Ami followed by soy sauce to remove grease and oxidation. We were looking for water to form a smooth sheet across the whole plate surface, which signals that there were no areas where grease was repelling water. Both plates were lightly buffed using a scouring pad and steel wool to create a matte surface. After the plates were prepared we the applied layers of methyl cellulose using a foam brush: Plate 1 had 6 thin layers of methyl cellulose painted on, each layer air dried before the next was applied and the layers were applied in brush stokes of the opposite direction of the one below. Plate 2 had 6 thin layers of methyl cellulose painted on, each layer air dried before the next was applied and the layers were applied in brush strokes of opposite direction of the ones below, and then it was heat set for 11 mins at 250 degrees.

Unetched plates, next to a control plate

Both plates were drawn into using an etching needle once all layers of methyl cellulose were completly done air drying.

Observations while drawing through both plates:
Plate 1: air dried, ground feels thicker than the one on plate 2. Hard to see if we are getting through all layers to the copper plate
Plate 2: heat set, the ground feels smoother and feels even more like we are not drawing through a ground.

For both plates we drew using a light touch and a sharp needle.

The plates were etched in Ferric Chloride bath, with a baume of 39 degrees, for 10 mins. After 10 mins, the plates were pulled out of the ferric to be rinsed very lightly under water to remove the ferric. At this point we observed the texture of the methyl cellulose ground; it was gooey and could be wiped a way with a finger.

Plate after being pulled out of etching bath

Gooey residue left by the “melting” ground

We let the plates air dry until the surface was clear of water, which created quite a lot of oxidization.

 

Heavily oxidized plates, etched for 10 minutes

Once dry we painted on ZMP stop out to half of the plate. As the stop out dried, due to oxidization, it began to crack. It took about two layers of stop out to fully cover the plates. We hypothesized that during etching the stop out might crack off due to its fragility.

Crackling of the stop out layer due to oxidization

Plates coming out of the bath

When rinsed under water the ground washed off, but some of the ground still had to be scrubbed away using Bon Ami and a rag. Then we printed both plates as follows:

Paper: Hahnemuhle Copperplate
Ink: Graphic Chemical INK CO Bone Black #514C etching ink
Modifier: burnt plate oi
Wiping: Tarlatan and newsprint

 

The resulting prints did reveal a couple of things. First, the 20 min etch, on both plates was lighter compared to the 10 min etch on the plates. We hypothesize this is due to the ground breaking down during the step etching process. Second, the heat set plate has line work that is much darker compared to the air dried plate. This suggests heat setting the methyl cellulose will consistently produce better results compared to air drying.

In conclusion, we see no reliable results from our tests of methyl cellulose as a ground. Its water soluble qualities make it hard to step etch and the ground is unreliable when in the ferric. Due to these results this is not a ground we will continue to research. 

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