<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31320037</termId><termName>fixer</termName><termType>PT</termType><termNote><![CDATA[ In silver gelatin photographic processing, a fixing bath contains a chemical, either sodium thiosulfate or ammonium thiosulfate, used to remove light sensitive silver halides from a photographic image and thus stabilize prints or film, fixing it, after it has been exposed to light. Ammonium thiosulfate was later adopted as a fixing salt because it acts three to four times faster, though is less stable. ]]></termNote><termCreatedDate>2026-03-30 20:26:15</termCreatedDate><relation><relationType>UF</relationType><termId>31320038</termId><termName>hypo</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31320039</termId><termName>hyposulfite</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31320040</termId><termName>hyposulphite</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31305895</termId><termName>fixative</termName><termType>PT</termType></relation><relation><relationType>BT</relationType><termId>31305951</termId><termName>photographic materials</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31373687</termId><termName>sodium thiosulfate</termName><termType>PT</termType></relation></term>  </Zthes>