1、INTERNATIONAL STANDARD ISO 3624 Second edition 1994-11-01 Photography - Processing chemicals - Specifications for potassium ferricyanide Photographie - Produits chimiques de traitemen t - Spkifica tions pour Ie ferricyanure de po tassium Weference nurnber OS0 3624:1994(E) ISO 3624: 1994(E) Foreword
2、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 interested in a subject for which a technical
3、committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of elect
4、rotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 3624 was prepared
5、 by Technical Committee lSO/TC 42, Photography. This second edition cancels and replaces the first edition (ISO 3624:i 976) which has been technically revised. 0 ISO 1994 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any
6、means, electronie or mechanical, including photocopyrng and mrcrofilm, without Permission in writing from the publisher. International Organization for Standardization Case postale 56 l CH-l 211 Geneve 20 l Switzerland Printed in Switzerland ii 0 ISO Introduction 0.1 This International Standard is o
7、ne of a series that establishes criteria of purity for chemicals used in processing photographic materials. General test methods and procedures cited in this International Standard are compiled in ISO 10349-1. This International Standard is intended for use by individuals with a working knowledge of
8、 analytical techniques which is possibly not always 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, rubber gloves and other protective apparel such as face
9、masks or aprons where appropriate. Normal precautions required in the Performance of any Chemical procedure should be exercised at all times but care has been taken to provide warnings for hazardous materials. Hazard warnings designated by a letter enclosed in angle brackets, , are used as a reminde
10、r 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 Chemical and physical require- ments for the suitability of
11、 a photographit-grade Chemical. The tests correlate with undesirable photographic effects. Purity requirements are set as low as possible consistent with these photographic effects. These criteria are considered the minimum requirements necessary to assure sufficient purity for use in photographic p
12、rocessing 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 availability of the higher-quality material. Every effo
13、rt 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 for use. Although the ultimate criterion for suitability
14、of such a Chemical is its successful Performance in an appropriate use test, the shorter, more economical test methods described in this International Standard are generally adequate. Assay procedures have been included in all cases where a satisfactory method is available. An effective assay requir
15、ement 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 tests All requirements listed in clause 4 are mandatory.
16、The physical appearance of the material and any footnotes are for general Information only and are not part of the requirements. ISO 3624: 1994(E) 0 ISO 0.3 Efforts have been made to employ tests which are capable of being run in any normally equipped laboratory and, wherever possible, to avoid test
17、s 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 improvements have been made in instrumentation for various analyses
18、. 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 User. In case of disagreement in results, the method called for
19、 in the specification shall prevail. Where a requirement states “to pass test”, however, alternative methods shall not be used. iv INTERNATIONAL STANDARD o ISO ISO 3624: 1994(E) Photography - Processing chemicals - Specifications for potassium ferricyanide 1 Scope This International Standard establi
20、shes criteria for the purity of photographit-grade potassium ferricyanide and describes the tests to be used to determine the purity. 2 Normative reference The following International Standard contains pro- visions which, through reference in this text, constitute provisions of this international St
21、andard. At the time of publication, the edition indicated was valid. All Standards are subject to revision, and Parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the Standard indicated below. Members of IEC
22、 and ISO maintain registers of currently valid International Standards. ISO 10349-1: 1992, Photography - Photographitgrade chemicals - Test me thods - Part 7: General. 3 General 3.1 Physical properties Potassium ferricyanide, K,Fe(CN), exists in the form of red crystals, fine granular crystals or a
23、crystalline powder. lt has a relative molecular mass of 329,27. 3.2 Hazardous properties Potassium ferricyanide is moderately toxic. Avoid inhalation and ingestion. When heated to de- composition or exposed to acid or acid fumes, it will emit highly toxic cyanide fumes. 3.3 Handling and storage No s
24、pecial precautions are required for the handling or storage of potassium ferricyanide except that contact with strong acids and exposure to high heat shall be avoided. 4 Requirements A summary of the requirements is shown in table 1. 5 Reagents and glassware All reagents, materials and glassware sha
25、ll conform to the requirements specified in ISO 10349-1 unless otherwise noted. The hazard warning Symbols used as a reminder in those Steps detailing handling operations are defined in ISO 10349-1. These Symbols are used to provide information to the user and are not meant to provide conformance wi
26、th hazardous labelling requirements as these vary from country to country. Table 1 - Summary of requirements Test Assay as K3Fe(CN)6 Appearance of Solution Limit 99,0 % ( m is the mass, in grams, of the test Sample; 32,92 is a conversion factor obtained from the mass of potassium ferricyanide equiva
27、lent to 1 mole of sodium thiosulfate (i.e. 329,2) x the conversion factor for millilitres to litres (i.e. 0,001) x 100 (for percentage). 7.2 Appearance of Solution 7.2.1 Specification The Solution shall be clear and free matter except for a slight flocculence. 7.2.2 Procedure from insoluble Prepare
28、a 100 g/l Solution of the test Sample. this Solution for clarity and any Sediment. Observe 1) Hazard warning Codes are defined in ISO 10349-1. 2) Commercially available analysed reagent is recommended. lf solutions are PO be prepared, see any quantitative analytical chemistry text. 2 This page intentionally left blank ISO 3624: 1994(E) 0 ISO 116s 37.040.30
