Direct Inkjet Resist printing with
Pigmented Inks
by Steve Greenfield aka Alien Steve
Epson 50000 driver set to no color correction. Coreldraw, set to no color profile. Colors set in RGB because all desktop printer drivers only accept RGB, and the double conversion would just add errors. 4.5 by 12 inch board, 0.015 inch thick fed directly without a carrier. Checked for headstrike by feeding two cardstock sheets stacked, 0.018 fed without any contact from the heads.
I am unsure of exactly which MIS pigmented inks these are, however they are specifically all pigment with no dye. Previous tests on paper and directly printed on untreated fabric show -no- running of any colors when wetted, even under running water. These were purchased as Magic Mix inks.
First try 04-26-2006: Plain Paper, No Color Adjustment, 720dpi. Wore clean rubber gloves. Scrubbed with a cheap, rather soft “scotch-brite” clone and Comet, until water sheets on the copper. Dried with clean non-dyed white paper towel. The cheap scrubby pad didn't really scratch it up much. Ink beads up rather badly, lines are from pizza wheels. Ink also seems to spread, so I didn't bother baking and etching. Click image for larger view.
It was late and clearly no point in baking it, so I left it and
went to bed.
Second Try 04-27-2006: Interesting. The board dried a bit
overnight. Hot water rinse,
the puddled drops ran right off but most of the ink was rather
difficult to remove fully. On inspection, the 100% black area showed
little lines in the direction of print head travel. Likely not a
blocked nozzle as I ran a nozzle check just before printing. No other
colors showed this banding. It appears that a lot more ink than was
needed got laid down.
Got a better scrubby pad. Scrubbed board with mix of ammonia, filtered
water, and isopropyl until water sheets over all of printable surface.
Rinsed in hot water, rinse in filtered water, final rinse in filtered
water with a small amount of isopropyl added. Dried with clean cotton
towel and a hair drier.
It's currently sitting in my food drier set at 145F.
I am uncertain that I can raise the pizza wheels in the Epson 5000. I
forgot, it was late last night, I noticed that it does not have a fully
straight paper path. When the PCB came out, it was forced to bend down
slightly. I worry that if I remove the pizza wheels, it will hit
something else, and if I merely raise them it will still hit the pizza
wheels.
I may need to drag the 1520 out and load it up with the inks as it's
paper path is straight through. For now, I'll print from the 5000 as-is
and disregard streaking from the pizza wheels.
New printer driver settings: Superfine 1440, Inkjet Backlit Film, Error Diffusion, No Color Adjustment. Reasoning: printer uses least ink for backlit film (next to transparency, which will only allow 360dpi max). Superfine 1440 means smaller ink drops (this Epson has variable droplet size) and a slower print speed, which means more time for the ink to dry.
Just fresh out of the printer, click for larger image:
Oops! Got the PCB and the test print in opposite directions.
Looks good! Ignore gloopy lines, those are from the pizza wheels. I don't think I let it warm up enough as it didn't feel very warm as it went into the printer, and it was cold as ice when it came out. A hot plate would warm it quicker, or a toaster oven on a higher setting. The Epson 5000 has an internal cooling fan, this probably didn't help. Despite the obvious puddling in all colors, the ink stayed within the lines. Cyan appears to have way too much ink, as do both full black (far right) and combo black (far left) to a lesser extent.
Less ink could be printed either by using a lighter color in the image itself, or the printer driver could have color adjustment turned on and the sliders adjusted there.
Several hours in the food dryer at 145F, and dry to the touch but slightly soft feeling is Black, Magenta, and Yellow. Cyan, Magenta/Yellow, and Combo Black are easily smeared. A few more hours, all are dry to the touch. The only place the ink spread outside the lines is where the pizza wheels crossed. I'm leaving it in the food dryer overnight, although when I print the next test I think I'll put it in the toaster oven so I can turn the temp up a bit higher.
04-28-2006: Black, Magenta, Yellow are dry even when rubbed fairly hard. Cyan, Magenta/Yellow, and Combo Black appear dry but feel slightly soft and crock a little when rubbed hard. Coated back and larger blank areas of front with Future Acrylic Floor Polish in preparation for etching, back into the food dryer.
FeCl acid bath, failure. First tried the method using a sponge brush to wipe etchant across the PCB, ink wiped off in the hot etchant. Used a baster to flush etchant across the rest of the board, even then the ink dissolved off. Spots where ink had puddled were first to go, presumably they weren't completely dry. Lasting long enough to make slight impressions: Black, Magenta, and Yellow. Cleaned and scrubbed board.
Tried the pre-etch suggested by some for toner transfer. Reprint failure- ink bled outside the lines all over board. Cleaned and scrubbed board, dried in toaster oven for an hour. Board slightly orange due to oxidization. Got board hot just before feeding into printer. Back to square one, but this time I'm drying it in the toaster oven to try and get the ink truly dry.
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Thanks,
Alien Steve
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