A Photographic Process

It was observed that polished and cleaned copper plates darken with an oxide film in the light but copper plates protected from the light remain bright.

An image may be formed on the copper by taking a clean copper plate and setting up an optical imaging system so that the image is formed on the bright copper plate.  The dark oxide layers form where the light is the strongest.

Cleaning

A flat sheet of copper foil plate is taken from the roll and flattened on the table, although the surface is smooth and shiny it is not bright. 

  1. Wash with acetone to de-grease

  2. Immerse foil in hydrochloric acid until dull finish become bright

  3. Now use subdued light

  4. Wash with distilled water

  5. Wash with acetone

  6. Dry with air blower

Image Formation

  1. Put flat, bright, copper plate on enlarger easel

  2. Expose to image on negative for a long time (use blue or UV light)

  3. See the darkening as copper oxide forms

  4. Expose until an image may be seen.

Fixing

  1. Put the exposed copper plate in neutral silver nitrate solution

  2. Wait until the silver forms on unexposed areas

  3. Remove plate and wash in water

  4. See silver image on copper base.

Alternative

  1. Put exposed copper plate in electroless gold solution

  2. Wait as gold deposits on unexposed areas

  3. Remove plate and wash in distilled water

  4. Clean plate with hydrochloric acid solution

  5. Wash in distilled water

  6. Put plate in silver nitrate solution

  7. Wait as silver deposits on copper areas not covered with gold

  8. Wash plate in distilled water and dry

  9. See image in silver and gold

Display

The image is visible and durable - will last many years in a clean atmosphere.