PURETCH description

Photo-etching is a time tested technique, and the good thing is now it can be virtually non-toxic without compromising resolution, plate durability and traditional plate manipulation. Puretch is a dry film photoresist for etching copper and other metals. It was designed for the highest resolution etching possible with a dry film; the thinner the film the higher the resolution. It is ideal for high resolution halftone positives and fine line etch applications. Puretch is for the intaglio printmaking purist that wants to traditionally etch the image and have complete control over the plate surface and edition.
Pronounced: purETCH, not purTECH

Puretch features
click to see enlarged details of resist and etched plates

• Puretch is THE thinnest photopolymer film on market!
• exposes with a positive, (negative working)
• thinnest film yields highest resolution etch capability
• 1/1200 inch lines and spaces
• yields consistent and predictable results
• easy to apply and etch
• use on any metal with most any etchant
• non-toxic and safe when used properly
• water based processing
• biodegradeable
• durable enough for deep etch with ferric chloride
• wide exposure latitude

Electro Etching
with Puretch

One of our customers writes in regarding the feasibility of using Puretch with the electrical etching process.

"I'm delighted to report that it works beautifully! It's very robust and reliable with this etching process. Even very small areas of resist are able to withstand the electric fields. It just hangs on -- I'm having a great success reproducing very fine details."

Two plates exposed with a point light Thicker films will not produce high resolution etchable resists. With thicker films, the light creeps in and undercuts the dots through the thickness of the film and hardens the film against the plate for all except large dots, thus not exposing the metal to the etchant. This diagram also demonstrates the need for a point light and not flourescents. Flourescents cause exaggerated undercutting because light is being cast from many different angles. The sun is the ultimate point light.

Puretch advantages

• Highest halftone resolution of dry film resists
• conventionally etched plates can print longer editions and/or be steel faced
• no pre-thinning of film necessary
• etched plates can be reworked with traditional processes
• available in 24 3/4" rolls to accommodate 24" wide plates
• all film is inspected when rolled, NO damaged 'end rolls'
• affordable price

Image applications

• digitally generated ink jet and laser printed halftones
• digitally imageset halftones and bitmaps
• kodalith halftones and positives
• photocopy on mylar
• india ink or toner wash on frosted mylar
• airbrush, pencil, pen or crayon drawing on vellum or frosted mylar...

Processing Basics

• film can be easily laminated by hand with common materials
• detailed instructions included with film

Other Puretch photoresist uses

• photo etching jewelry and serving trays
• photo engraved metal plaques or signs
• fine line printed circuit board production (pcb)
• chemical milling
• Electro Etching process
• Steel Pad printing cliches