Back in the early 1980's I had a discussion with two senior Ilford managers and a research chemist over a business lunch. The chemist had been involved in the scaling up production of Paterson chemistry which was once made for them by Ilford, he commented that often there were unnecessary ingredients in Crawley's formulae and there were no benefits of 3 developing agents.
If you compare this formula you'll see the simplicity of Ilford's Phenidone Glycin developer compared to the examples above.
Ilford "Phenidone Glycin" Developer Patent Formula (Ilfosol)
Phenidone 1.75g
Glycin 50g
Potassium Sulphite (anhyd) 297g
Potassium Hydroxide13.4g (to pH 9.9
Water to 1 litre
Use 1+7 (same as Acuspeed)
Crawley FX-11 (Crawley's published Speed increasing developer)
Phenidone 0.25g
Hydroquinone 5g
Glycin 1.5g
Sodium Sulphite (anhyd) 125g
Borax 2.5g
Potassium Bromide 0.5g
Water to 1 litre
Use Full Strength
This can’t be made up as a concentrate due to the high level of Sodium Sulphite, Ilford use Potassium Sulphite as it has higher solubility.
Ian
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