1、INTERNATIONAL STANDARD Second edition 1993-02-0 1 Photography - Processing chemicals - Specifications for anhydrous sodium acetate Photographje - Produits chimiques de traitement - Specifications pour Iacktate de sodium anhydre - -_ _ - - - -.- - - - - -_-_ -_-_._ _- .- _ _._ Reference number ISO 39
2、43: 1993(E) ISO 3943:1993(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national Standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Esch member body interest
3、ed in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
4、Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Inter- national Standard requires approval by at least 75 % of the member bodies casting a vote. In
5、ternational Standard ISO 3943 was prepared by Technical Committee ISO/TC 42, Photography. This second edition cancels and replaces the fit-st edition (ISO 3943:1976), which has been technically revised. 0 ISO 1993 All rights reserved. No part of this publication may be reproduced or utilized in any
6、form or by any means, electronie or mechanical, including photocopying and micr ofilm, without permission in writing from the publisher. International Organization for Standardization Case Postale 56 l CH-121 1 Geneve 20 l Switzerland Printed in Switzerland ii ISO 3943:1993(E) Introduction 0.1 This
7、International Standard is one of a series that establishes cri- teria of purity for chemicals used in processing photographic materials. General test methods and procedures cited in this International Stan- dard are compiled in Parts 1, 3, 5, 6 and 7 of ISO 10349. This International Standard is inte
8、nded for use by individuals with a working knowledge of analytical techniques, which may not always be the case. Some of the procedures utilize caustic, toxic or otherwise hazardous chemicals. Safe laboratory practice for the handling of chemicals requires the use of safety glasses or goggles, rubbe
9、r gloves and other protective apparel such as face masks or aprons where ap- propriate. Normal precautions required in the Performance of any Chemical procedure are to be exercised at all times but care has been taken to provide warnings for hazardous materials. Hazard warnings designated by a lette
10、r enclosed in angle brackets, , are used as a reminder in those Steps detailing handling operations and are defined in ISO 10349-1. More detailed information regarding hazards, handling and use of these chemicals may be available from the manufacturer. 0.2 This International Standard provides Chemic
11、al and physical re- quirements for the suitability of a photographit-grade Chemical. The tests correlate with undesirable photographic effects. Purity require- ments are set as low as possible consistent with these photographic effects. These criteria are considered the minimum requirements necessar
12、y to assure sufficient purity for use in photographic processing solutions, except that if the purity of a commonly available grade of Chemical exceeds photographic processing requirements and if there is no economic penalty in its use, the purity requirements have been set to take advantage of the
13、availability of the higher-quality material. Every effort has been made to keep the number of requirements to a minimum. Inert impurities are limited to amounts which will not unduly reduce the assay. All tests are performed on samples “as received” to reflect the condition of materials furnished fo
14、r use. Although the ultimate criterion for suitability of such a Chemical is its successful Performance in an appropriate use test, the shorter, more economical test methods de- scribed in this International Standard are generally adequate. Assay procedures have been included in all cases where a sa
15、tisfactory method is available. An effective assay requirement serves not only as a safeguard of Chemical purity but also as a valuable complement to the identity test. Identity tests have been included whenever a possibility exists that another Chemical or mixture of chemicals could pass the other
16、tests. All requirements tisted in clause 4 are mandatory. The physical ap- pearance of the material and any footnotes are for general information only and are not patt of the requirements. . . . Ill ISO 3943:1993(E) 0.3 Efforts have been made to employ tests which are capable of being run in any nor
17、mally equipped laboratory and, wherever possible, to avoid tests which require highly specialized equipment or techniques. Instrumental methods have been specified only as alternative methods or alone in those cases where no other satisfactory method is available. Over the past few years, great impr
18、ovements have been made in instrumentation for various analyses. Where such techniques have equivalent or greater precision, they may be used in place of the tests described in this International Standard. Correlation of such alternative procedures with the given method is the responsibility of the
19、User. In case of disagreement in results, the method called for in the specifi- cation shall prevail. Where a requirement states “to pass test”, how- ever, alternative methods shall not be used. iv INTERNATIONAL STANDARD ISO 3943:1993(E) Photography - Processing chemicals - Specifications for anhydr
20、ous sodium acetate 1 Scope This International Standard establishes criteria for the purity of photographit-grade anhydrous sodium acetate and describes the tests to be used to deter- mine the purity. 2 Normative references The following Standards contain provisions which, through reference in this t
21、ext, constitute provisions of this International Standard. At the time of publi- cation, the editions indicated were valid. All stan- dards are subject to revision, and Parties to agreements based on this International Standard are encouraged to investigate the possibility of ap- plying the most rec
22、ent editions of the Standards in- dicated below. Members of IEC and ISO maintain registers of currently valid International Standards ISO 385-1:1984, Laboratory glassware - Burettes - Part 1: General requirements. ISO 10349-1 :1992, Photography - Photographic- grade chemicals - Test methods - Part 1
23、: General. ISO 10349-3:1992, Photogt-aphy - Photographic- q-ade chemicals - Test methods - Part 3: Determi- nation of matter insoluble in ammonium hydroxide Solution. ISO 10349-5:1992, Photography - Photographic- grade chemicals - Test methods - Part 5: Determi- nation of heavy metals and iron conte
24、nt. ISO 10349-6:1992, Photography - Photographit- grade chemicals - Test methods - Part 6: Determi- nation of halide content. ISO 10349-7:1992, Photography - Photographic- grade chemicals - Test methods - Part 7: Defermi- nation of alkalinity or acidity. 3 General 3.1 Physical properties Anhydrous s
25、odium acetate (CH,COONa) is a white powder or grey-white flakes. lt has a relative mol- ecular mass of 82,03. 3.2 Hazardous properties Sodium acetate is not hazardous when handled with normal precautions. Refer to the manufacturer for additional information. 3.3 Handling and storage Sodium acetate i
26、s hygroscopic and shall be stored in a tightly sealed Container. 4 Requirements A summary of the requirements is shown in table 1. 1 ISO 3943:1993(E) Test Table 1 - Summary of requirements Limit Subclause International Standard in which test method is given Assay (as CH,COONa) Insoluble matter (as p
27、recipi- tate of Calcium, magnesium and ammonium hydroxides) Heavy metals (as Pb) Iron (Fe) Halides (as Cl-) Alkalinity (as NaOH) Acidity (as CH,COOH) Appearance of Solution 98,5 % (m/m) min. 0,5 Oh (m/m) max. 0,005 % (m/m) max. 0,005 % (m/m) max. 0,3 Oh (m/m) max. 0,04 Oh (m/rn) max. 1,0 Oh (m/m) ma
28、x. Clear and free from insoluble matter except for a slight flocculence 7.1 ISO 3943 7.2 ISO 10349-3 7.3 ISO 10349-5 7.4 ISO 10349-5 7.5 ISO 10349-6 7.6 ISO 10349-7 7.7 ISO 10349-7 7.8 ISO 3943 NOTE - m/m = mass/mass 5 Reagents and glassware All reagents, materials and glassware shall conform to the
29、 requirements specified in ISO 10349-1 unless otherwise noted. The hazard warning Symbols used as a reminder in those Steps detailing handling op- erations are defined in ISO 10349-1. These Symbols are used to provide information to the user and are not meant to provide conformance with hazardous la
30、belling requirements, as these vary from country to country. 6 Sampling See ISO 10349-1. 7.1.2.2 Perchlorit acidp), Standard volumetric sol- ution, c(HCI0,) = 0,100 mol/1 (10,046 g/l) in glacial acetic acid (DANGER: ). 7.1.3 Procedure Weigh a test Portion of 0,19 g to 0,21 g to the nearest 0,000 1 g
31、 and transfer it to a clean and dry 125 ml glass-stoppered conical flask. Add 25 ml of acetic acid (7.1.2.1) ( ) to this flask and dissolve the test portion. Prepare a blank by adding 25 ml of acetic acid (7.1.2.1) to a second clean and dry flask. Titrate the test Solution and blank to the colorimet
32、ric endpoint3) with the perchloric acid Solution (7.1.2.2) ( ). 7 Test methods 7.1.4 Expression of results 7.1 Assay 7.1 .l Specification The assay, expressed as a percentage by mass of CH,COONa, is given by 8,20 c(Vs - VS) m where Content of CH,COONa shall be 98,5 % (m/m) min. 7.1.2 Reagents c is t
33、he actual concentration, expressed in moles of HCIO, per litre, of the perchloric acid Solution (7.1.2.2); 7.1.2.1 Acetic acid, glacial (CH,COOH) (DANGER: V S is the volume, in millilitres, of the ) perchloric acid Solution used to resch the 1) Hazard warning Codes are defined in ISO 10349-1. 2) Com
34、mercially available Standard reagent is recommended. If solution is to be prepared, see any quantitative analytical chemistry text. 3) Methyl violet dissolved in chlorobenrene (1 g/l) may be used as an indicator. The Solution is titrated to the first true green endpoint. 2 ISO 3943:1993(E) endpoint
35、for the titration of the test sol- ution; V B is the volume, in miliilitres, of the perchloric acid solution used to resch the endpoint for the titration of the blank; m is the mass, in grams, of the test Portion; 8,20 is a conversion factor obtained from the mass of sodium acetate equivalent to 1 m
36、ole of perchloric acid (i.e. 82,03) x the conversion factor for millilitres to litt-es (i.e. 0,001) x 100 %. 7.2 Insoluble matter content (as a precipitate of Calcium, magnesium and ammonium hydroxides) the Sample prepared in accordance with ISO 10349-5:1992, 7.2. Use 5 ml of the iron Standard prepa
37、red in accordance with ISO 10349-5. 7.5 Halides content (as Cl-) 7.5.1 Specification Maximum content of halides shall be 0,3 % (m/m). 7.5.2 Procedure Determine the percentage of halides (expressed as Cl-) in accordance with ISO 10349-6. 7.6 Alkalinity (as NaOH) 7.6.1 Specification 7.2.1 Specificatio
38、n Maximum free alkali content shall be 0,04 % (m/m). Maximum content of insoluble matter shall be 0,5 % (mfm). 7.2.2 Procedure Determine the percentage of insoluble matter in ac- cordante with ISO 10349-3. 7.3 Heavy metals content (as Pb) 7.3.1 Specification Maximum content of heavy metals shall be
39、0,005 YO (m/m). 7.6.2 Procedure Prepare a test solution in accordance with ISO 10349-7 using a test Portion of 4,9 g to 5,l g. If the prepared test solution turns pink when the indi- cator is added, determine the percentage alkalinity as sodium hydroxide using a factor K equal to 4,00 in the calcula
40、tion given in ISO 10349-7. 7.7 Acidity (as CH,COOH) 7.7.1 Specification Maximum free acid content shall be 1,O % (m/m). 7.3.2 Procedure 7.7.2 Procedure NOTE 1 The Standard for the iron test (7.4) is prepared in the same way as the heavy metals Standard. Determine the percentage of heavy metals in ac
41、- cordante with ISO 10349-5. Use a test Portion of 0,90 g to 1,lO g of the Sample prepared in accord- ante with ISO 10349-5:1992, 7.2. Use 5 ml of the heavy metals Standard prepared in accordance with ISO 10349-5:1992, 8.1.1. 74 . Iron content 7.4.1 Specification Maximum content of iron shall be 0,0
42、05 % (m/m). 7.4.2 Procedure Determine the percentage of iron in accordance with ISO 10349-5. Use a test Portion of 0,90 g to IJ0 g of If the prepared test Solution in the alkalinity deter- mination remains clear when the indicator is added, determine the percentage acidity as acetic acid in accordan
43、ce with ISO 10349-7. Use a factor K equal to 6,Ol in the calculation given in ISO 10349-7. 7.8 Appearance of solution 7.8.1 Specification The solution shall be clear and free from insoluble matter except for a slight flocculence. 7.8.2 Procedure Dissolve a test Portion of IO,0 g in 50 ml of water an
44、d dilute to 100 ml with water. Let this solution stand for 30 min at ambient temperature (20 “C to 27 “C). Ob- serve the solution for colour and clarity. 3 ISO 3943:1993(E) UDC 771.7:661.833.712 Descriptors: photography, photographic materials, photographic chemicais, purity criteria, tests, Chemical analysis. sodium acetate, specifications, materials specifications, Price based on 3 pages -
