Platona printing paper
Britannia Works Company Limited

Platinotype: The following is taken from the 'Readers Ask' column, written by Neville Maude, in Amateur Photographer magazine for 7th March 1962.
A contact printing process (from the time when negatives were large enough to make sizeable contact prints) based on the reduction of a ferric salt to ferrous by the action of light. The ferrous salt was used to reduce a platinum compound e.g potassium chloroplatinite, to the platinum metal that then formed the image. Good points were the great permanence of the image and the way it lay on the natural suface of the paper. Very hard negatives were needed. Moreover, platinum is expensive and much goes down the drain with each print. Palladium has been used as a substitute, but even this is expensive.


The Platona tin, made by Huntley, Boorne and Stevens, Reading, measures some 170mm long and 65mm diameter. The screw top lid has side pieces that provide a grip and enable it to be tightend and loosened more easily. Inside the lid is a sealing ring that compresses against the top of the tube and prevents the paper from completely drying out.

The lid (left) and the label (above) both show the tin to have been sold by The Britannia Works Company Limited of Ilford, London. This dates the tin to around 1899-1900.

PURE PLATINUM PAPER AT POPULAR PRICES.
In two Varieties, ROUGH and SMOOTH.

DIRECTIONS.
TO OPEN -Tear off the narrow strip of tin from lid, and store the paper in an air-tight tube as usual with platinum papers.
PRINTING - Printing frame and pad should be quite dry. Print until all details are faintly visible. Examine in weak light only.

DEVELOPING FORMULA Stock Solution.
Potassium Oxalate 2ozs. (70 grammes); Potassium Phosphate ½oz (17 grammes); Water 14ozs (500cc)
This solution is better if slightly acid, if it is not so, 60 grains (5 grammes) oxalic acid should be added.
If unable to obtain Potassium Phosphate, the Sodium Phosphate may be substituted, but the former is preferable.
Dissolve the salts in hot water and allow to cool. This solution will keep indefinitely.
For use take 1 part Stock Solution and 1 part Water.
Develop in weak daylight or in artificial light, floating the prints face downwards in the solution. The image does not lose in fixing.
FIXING.
Pure Hydrochloric Acid 1oz. (12cc); Water 80ozs. (1000cc)
Immerse prints for about five minutes each in three consecutive baths, and then give them a final washing in water for 15 minutes. The prints are then ready to be dried and mounted.

This page last updated: 6th September 2009