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Developer and fixer chemistry

Kodak names Rapid Fixer Solution B a hardener on E-103CF — not on the pack-in

Shows that Kodak E-103CF (© 2010) labels Rapid Fixer a “fast-acting hardening fixer” whose Solution B is “the hardener concentrate” and whose typical- dilution cell reads “1:3 plus Part B (hardener),” while the Kodak Rapid Fixer pack-in (© Kodak 2015, code 20370811) publishes Solution A/B preparation charts for film and paper without using the words hardener or hardening and isolates Solution B as omit-able only in the Dektomatic note; set beside Ilford Rapid Fixer’s hardener ban and Multigrade FB Classic’s rejection of hardening fixers for paper, so the Kodak A+B bath is not the same published kind of claim as Ilford’s non-hardening Rapid path.

Published by AnalogFixer ·

Kodak Rapid Fixer ships as two liquid concentrates. Whether the second part is a hardener depends on which Kodak document is open. The 2010 chemicals summary names Solution B as the hardener concentrate and calls the product a hardening fixer. The 2015 pack-in instruction sheet that actually charts how the bath is prepared never uses those words.

This is a document comparison of dated Kodak and Ilford sheets. It is not a mixing, handling, reuse or disposal guide, and it does not treat any sheet as current beyond the revisions named below.

E-103CF calls Solution B the hardener

Kodak publication E-103CF, Chemicals for KODAK PROFESSIONAL Black-and-White Films, Eastman Kodak Company © 2010 (manufacturer PDF via Wayback capture 25 September 2012), puts Rapid Fixer in the fixers table with a typical-dilution cell that already contains the label:

1:3 plus Part B (hardener)

The same row gives solution temperature and time as 65 to 70°F (18 to 21°C) and 2 to 10 minutes “depending on film and fixer combination.”

The descriptive block on the same sheet does not leave the function of Part B open. Rapid Fixer is “a fast-acting hardening fixer” for machine, tray or tank use. It “consists of two liquid concentrates: Solution A (the fixer concentrate) and Solution B (the hardener concentrate),” and is “for use with film and paper.”

On E-103CF, then, three claims travel together: the product class is hardening fixer; Solution B is the hardener concentrate; the typical dilution statement includes Part B under that hardener gloss.

Matrix showing Solution B named as hardener on E-103CF but absent from pack-in instructions.

The pack-in charts A and B without the hardener word

The Kodak Rapid Fixer pack-in instruction sheet (© Kodak 2015, code 20370811; one page) is a different document class. It is the sheet that publishes preparation charts for films and plates and for papers. Both charts have columns for Solution A and Solution B. Manual film times on that sheet are given for a fresh fixing bath at 18 to 24°C / 65 to 75°F — most Kodak professional films 2 to 4 minutes; Kodak T-MAX Professional Films 3 to 5 minutes.

What the pack-in examined here does not do is name the function of Solution B. A full-text read of that file finds no occurrence of harden, hardener or hardening. Solution B appears as a chart ingredient and as the object of one machine exception: for the Kodak Dektomatic 65 Paper Processor, the sheet says to use Solution A diluted one part to three parts water and notes “Do not use Solution B in this processor.” That note makes Solution B optional for one named machine. It still does not call B a hardener.

So the pack-in’s silence is not the absence of Solution B from the bath. Film and paper preparation charts both include B. The silence is the absence of the hardener label that E-103CF prints next to the same part name.

E-103CF, © 2010 Rapid Fixer pack-in, © Kodak 2015, code 20370811
Product class wording “Fast-acting hardening fixer” No hardening / hardener wording on that sheet
Solution B named as “The hardener concentrate” / “Part B (hardener)” Solution B only; function not labeled
Typical / charted bath “1:3 plus Part B (hardener)” Film and paper charts include Solution A and Solution B; Dektomatic path omits B
Temperature band on the Rapid row / manual block 65 to 70°F (18 to 21°C) 18 to 24°C / 65 to 75°F
Time framing 2 to 10 minutes depending on film and fixer combination Most professional films 2–4 minutes; T-MAX Professional Films 3–5 minutes

The temperature and time rows are secondary disagreements between the same manufacturer’s chemistry summary and pack-in. They matter here only as further proof that the two documents are not interchangeable copies of one Rapid Fixer specification. The load-bearing split is the hardener label itself.

Film sheets that name Rapid Fixer do not restore the label

Kodak publication F-4016 for T-MAX 100, June 2018, under FINAL STEPS, tells the reader to fix in Kodak Rapid Fixer for 3 to 5 minutes at 65 to 75°F (18 to 24°C). It strongly recommends Rapid Fixer to keep fixing times short, and it forks other named fixers (Kodak Fixer or KODAFIX Solution) to a longer band. It does not mention Solution A, Solution B, Part B, or hardener.

F-4016 therefore points at the product without republishing E-103CF’s hardening-fixer description. A reader who has only the film sheet and the pack-in has the A/B charts and no hardener word. A reader who has E-103CF has the hardener word. These sources do not reconcile those presentations.

Ilford’s Rapid path is a different kind of claim

Ilford Rapid Fixer, July 2010, is not silent. It calls itself a “non-hardening rapid fixer” and states that it “must not be used with fix hardeners.” Multigrade FB Classic, October 2013, independently rejects hardening fixers for paper because they reduce washing efficiency, names Rapid Fixer and Hypam as non-hardening fixers, and in its optimum-permanence sequence says not to add a hardener to the fixer.

That Ilford language is already used in Hypam’s hardener doubles film fixing time — and discourages its own use for Ilford’s own hardener-optional product. What it contributes here is cross-brand comparison, not a second Hypam time table. Kodak’s E-103CF Rapid path is published as a hardening fixer with Solution B as hardener. Kodak’s pack-in still charts Solution B into the paper bath while never using the hardener word. Ilford’s Rapid path is published as non-hardening and hardener-forbidden. Sharing the commercial phrase “rapid fixer” does not make those published roles the same.

What these sheets do not settle

None of these documents is used here to identify the chemical composition of Solution B, to prove that the 2015 pack-in’s unlabeled B is or is not chemically a hardener, or to rank Kodak Rapid Fixer against Ilford Rapid Fixer for speed, capacity or wash behaviour. The dilution fork on the same E-103CF Rapid row is treated in AJ-3 names Rapid Fixer film 1:3 and paper 1:7 — E-103CF’s Rapid row does not. Capacity figures and Ilford’s optional Hypam Hardener path are separate kinds of claim already handled on this site. No later Kodak chemicals catalogue or pack-in revision was examined for this article.

The usable statement is narrower. In the sources examined here, “Kodak Rapid Fixer Solution B” is a hardener only where E-103CF says so. The pack-in that charts A and B for film and paper does not say so. Collapsing the product into one hardening or non-hardening label without naming the document erases that split.

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