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Developer and fixer chemistry

Hypam’s hardener doubles film fixing time — and discourages its own use

Sets Ilford Rapid Fixer’s absolute hardener ban beside Hypam’s optional hardener path in the August 2002 Hypam fact sheet, shows that the same Hypam sheet doubles average minimum film fixing time at 20°C from 2–5 to 4–10 minutes when hardener is used and states that higher hardener doses reduce fixing and washing efficiency, and records that Multigrade FB Classic (October 2013) independently rejects hardening fixers for paper because they reduce washing efficiency while naming both Rapid Fixer and Hypam as non-hardening products.

Published by AnalogFixer ·

Ilford sells two ammonium-thiosulphate rapid fixers that look interchangeable until the hardener column is read. Rapid Fixer is a non-hardening concentrate that “must not be used with fix hardeners.” Hypam is sold as a fixer-and-hardener system: the fixer alone is non-hardening, and a separate Hypam Hardener concentrate can turn the working bath into a hardening film fixer. The same Hypam sheet that publishes that option also says general hardener use is “no longer recommended,” and its own time table doubles film fixing time when hardener is present.

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

Two product rules, not one house rule

Ilford Rapid Fixer, July 2010 Ilford Hypam Fixer & Hardener, August 2002 Ilford Multigrade FB Classic, October 2013
Document class Generic film and paper fixer fact sheet Fixer-and-hardener system fact sheet Fibre-base paper technical information
Fixer without add-on “Non-hardening rapid fixer” “Non-hardening rapid fixer” usable without hardener for film and paper Names Rapid Fixer and Hypam as “non-hardening fixers”
Hardener rule “Must not be used with fix hardeners” Optional Hypam Hardener for black-and-white films; “not recommended” for any paper fixing “The use of a hardening fixer is not recommended as it reduces washing efficiency”; “Do not add a hardener to the fixer” in the permanence sequence
Film fixing time published here at 1+4 Average minimum 2–5 minutes at 20°C, fresh fixer, no hardener column Average minimum 2–5 minutes without hardener; 4–10 minutes with hardener, same 20°C fresh-fixer framing Paper sheet: Rapid Fixer or Hypam 1+4 for one minute at 18–24°C (paper, not film)

Rapid Fixer’s ban is categorical. Hypam’s permission is conditional and product-specific. Calling both sheets “Ilford says don’t harden” collapses a prohibition, an optional add-on, and a paper-side rejection into one sentence they do not share.

Every Hypam figure below is from the August 2002 revision (footer 02033.www August 2002). Rapid Fixer hardener language is taken from the July 2010 sheet; the same non-hardening description and hardener ban already appear in the August 2002 Rapid Fixer revision. Multigrade FB Classic is the October 2013 paper sheet. Whether later inaccessible revisions still say the same thing is outside what these files examined here can prove.

Bar chart showing Hypam hardener doubling film fixing time while the sheet discourages routine use.

The load-bearing numbers are on one Hypam page

Hypam’s fixing-time table is built as a with/without comparison. For general-purpose film at 1+4, average minimum fixing time in fresh fixer at 20°C (68°F) is 2–5 minutes without hardener and 4–10 minutes with hardener. The same 2–5 / 4–10 pair is given for other specialist, X-ray and graphic-arts materials. Paper rows are marked n/a in the hardener column.

The prose on the same sheet states the consequence without relying on the table layout: if a fix hardener is used in film processing, recommended fix and wash times need to be extended; fix-plus-hardener time will be between 4 and 10 minutes, and the subsequent wash 10–20 minutes. That wash band is Hypam’s hardener-path figure. It is not a claim about Rapid Fixer’s ordinary 5–10 minute film-wash band on a different sheet, and it is not reconciled to Multigrade’s paper-wash figures elsewhere on this site.

Hardener amount is itself tiered on that sheet:

  • Full hardening, when fix and wash times can be extended: maximum 1 part hardener to 40 parts working-strength Hypam (stated as 24 ml/l).
  • Restricted times, minimum useful addition: about 3–6 ml hardener per litre of working-strength Hypam, with “negligible effect on the fix and wash efficiency.”
  • Restricted times, higher band: 10–20 ml/l, which “will give a definite increase to the hardness” while “fixing and washing efficiency are reduced,” with the films still “adequately fixed and washed for most purposes.”

So the sheet that sells the hardener also publishes the efficiency cost of using more of it when the process cannot be lengthened. The doubled film clock and the reduced-efficiency note are specifications on the hardener path, not community lore attached afterward.

The same sheet narrows when hardener is recommended

Immediately after introducing Hypam Hardener, the August 2002 sheet says modern camera films are usually hardened enough in manufacture that “the general use of a fix hardening agent is no longer recommended.” Hardener is recommended only if process temperature is above 30°C (86°F), drying performance is poor, shorter drying times are needed, or there is a risk of physical damage (for example in a roller-transport processor). For paper, hardener “is not recommended” with no parallel exception list.

Later in the sheet the same judgment is restated for common manual and deep-tank paths: additional hardening from a fixer hardener is “not usually needed or recommended” for dish/tray, spiral tank, deep tanks, rotary processors, dip-and-dunk and short-leader processors unless one of those temperature, drying or damage conditions applies. Roller-transport remains the machine class singled out for possible need.

That is an internal tension, not a misprint. Hypam Hardener is a published product path with published times. The recommendation framing on the same document treats that path as exceptional. Rapid Fixer removes the path entirely.

What the paper sheet adds — and what it does not

Multigrade FB Classic (October 2013) is a paper document. It does not republish Hypam’s film hardener times. What it contributes to this comparison is the paper-side category statement: hardening fixer is not recommended because it reduces washing efficiency; Rapid Fixer and Hypam are non-hardening fixers; and the optimum-permanence sequence says not to add a hardener to the fixer.

That matches Hypam’s paper prohibition. It also explains why Multigrade can call Hypam non-hardening while the Hypam fact sheet still describes a hardener concentrate: the paper sheet is describing the Hypam fixer used without hardener, which is the only paper path Hypam itself endorses. It is not evidence that Hypam Hardener does not exist, and it is not a film-processing instruction.

None of these three sheets ranks Rapid Fixer against Hypam for speed, capacity or permanence. Rapid Fixer’s 2–5 minute film band and Hypam’s 2–5 minute no-hardener band are parallel non-hardening figures at the same dilution and temperature framing; Hypam’s 4–10 minute band is a different process. Collapsing them into one “Ilford film fixing time” erases the hardener column that creates the difference. Kodak’s E-103CF Rapid path publishes Solution B as a hardener where Ilford forbids one; see Kodak names Rapid Fixer Solution B a hardener on E-103CF — not on the pack-in. Ilford’s paper-only 1+9 dilution clause sits on the same Rapid Fixer sheet family; see Ilford’s manual 1+9 is a paper clause, not a film path.

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