《BS-ISO-423-1994.pdf》由会员分享,可在线阅读,更多相关《BS-ISO-423-1994.pdf(14页珍藏版)》请在三一文库上搜索。
1、BRITISH STANDARD BS ISO 423:1994 Implementation of ISO 423:1994 Photography Processing chemicals Specifications for hydroquinone Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS ISO 423:1994 This British Standard, having been prepared unde
2、r the direction of the Consumer Products and Services Sector Board (W/-), was published under the authority of the Standards Board and comes into effect on 15 March 1995 BSI 02-2000 The following BSI references relate to the work on this standard: Committee reference CPM/14 Draft for comment 90/4599
3、0 DC ISBN 0 580 23917 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee CPM/14, Photographic chemicals and processing, upon which the following bodies were represented: British Institute of Non-destructive Testing British
4、 Photographic Association Chemical Industries Association Department of the Environment (Water Directorate) Royal Photographic Society Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI B
5、S ISO 423:1994 BSI 02-2000i Contents Page Committees responsibleInside front cover National forewordii Forewordiii Text of ISO 4231 Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS ISO 423:1994 ii BSI 02-2000 National foreword This British
6、 Standard reproduces verbatim ISO 423:1994 and implements it as the UK national standard. It supersedes BS 3103:1978, which is withdrawn. This British Standard is published under the direction of the Consumer Products and Services Sector Board whose Technical Committee CPM/14 has the responsibility
7、to: aid enquirers to understand the text; present to the responsible international committee any enquiries on interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. NOTEInternational and European
8、 Standards, as well as overseas standards, are available from Customer Services, BSI, 389 Chiswick High Road, London W4 4AL. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance
9、 with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the ISO title page, pages ii to iv, pages 1 to 5 and a back cover. This standard has been updated (see copyright date) an
10、d may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006,
11、Uncontrolled Copy, (c) BSI ISO 423:1994(E) ii BSI 02-2000 Contents Page Forewordiii Introduction1 1Scope1 2Normative references1 3General2 3.1Physical properties2 3.2Hazardous properties2 4Requirements2 5Reagents and glassware2 6Sampling2 7Test methods2 7.1Assay2 7.1.1 Specification2 7.1.2 Reagents2
12、 7.1.3 Apparatus2 7.1.4 Procedure2 7.1.5 Expression of results3 7.2Identity tests3 7.2.1 Melting point3 7.2.2 Infrared spectrum3 7.3Residue after ignition3 7.3.1 Specification3 7.3.2 Procedure3 7.4Heavy metals content3 7.4.1 Specification3 7.4.2 Procedure3 7.5Iron content3 7.5.1 Specification3 7.5.2
13、 Procedure4 7.6Appearance of solution4 7.6.1 Specification4 7.6.2 Reagent4 7.6.3 Procedure4 Annex A (informative) Preparation of standard ammonium cerium(IV) hexanitrate solution, c(NH4)2Ce(NO3)6 = 0,1 mol/l5 Figure 1 Reference infrared spectrum of hydroquinone (KBr plate)4 Table 1 Summary of requir
14、ements2 Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 423:1994(E) BSI 02-2000iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of
15、preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental,
16、 in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Pu
17、blication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 423 was prepared by Technical Committee ISO/TC 42, Photography. This second edition cancels and replaces the first edition (ISO 423:1976), which has been technica
18、lly revised. Annex A of this International Standard is for information only. Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI
19、ISO 423:1994(E) BSI 02-20001 Introduction 0.1 This International Standard is one 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 parts 1, 4 and 5 of ISO 1
20、0349. This International Standard is intended 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 th
21、e use of safety glasses or goggles, rubber gloves and other protective apparel such as face masks or aprons where appropriate. 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
22、. Hazard warnings designated by a letter 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
23、 International Standard provides chemical and physical requirements for the suitability of a photographic-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 considere
24、d the minimum requirements necessary 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
25、 been set to take advantage of the 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
26、condition of materials furnished for 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 described in this International Standard are generally adequate. Assay procedures have been
27、 included in all cases where a satisfactory 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 o
28、f chemicals could pass the other tests. All requirements listed in clause 4 are mandatory. The physical appearance of the material and any footnotes are for general information only and are not part of the requirements. 0.3 Efforts have been made to employ tests which are capable of being run in any
29、 normally 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
30、improvements 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
31、the user. In case of disagreement in results, the method called for in the specification shall prevail. Where a requirement states “to pass test”, however, alternative methods shall not be used. 1 Scope This International Standard establishes criteria for the purity of photographic-grade hydroquinon
32、e and describes the tests to be used to determine the purity. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards ar
33、e subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 565:199
34、0, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings. ISO 10349-1:1992, Photography Photographic-grade chemicals Test methods Part 1: General. Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) B
35、SI ISO 423:1994(E) 2 BSI 02-2000 ISO 10349-4:1992, Photography Photographic-grade chemicals Test methods Part 4: Determination of residue after ignition. ISO 10349-5:1992, Photography Photographic-grade chemicals Test methods Part 5: Determination of heavy metals and iron content. 3 General 3.1 Phys
36、ical properties Hydroquinone, C6H4(OH)2, is in the form of white or almost white needle-like crystals or a free-flowing crystalline powder. It has a relative molecular mass of 110,10. 3.2 Hazardous properties Hydroquinone can cause eye injuries and dermatitis upon contact with eyes and skin, respect
37、ively. Avoid all skin contact, do not breathe the dust or vapour. Wear eye protection and gloves when handling. Contact the manufacturer for further information. 4 Requirements A summary of the requirements is shown in Table 1. 5 Reagents and glassware All reagents, materials and glassware shall con
38、form 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 with haz
39、ardous labelling requirements as these vary from country to country. 6 Sampling See ISO 10349-1. 7 Test methods 7.1 Assay 7.1.1 Specification Content of hydroquinone C6H4(OH)2 shall be 99,0 % (m/m) min. 7.1.2 Reagents 7.1.2.1 Ammonium cerium(IV) hexanitrate, (NH4)2Ce(NO3)6, standard volumetric solut
40、ion 0,10 mol/l1)2). 7.1.2.2 Diphenylamine indicator solution Dissolve 1 g of diphenylamine in 100 ml of sulfuric acid (7.1.2.3) ()3). 7.1.2.3 Sulfuric acid, H2SO4, standard volumetric solution of 0,05 mol/l1)4). 7.1.3 Apparatus Usual laboratory apparatus and, in particular, the following. 7.1.3.1 Wa
41、tch glass 7.1.3.2 Burette, of 50 ml capacity. 7.1.4 Procedure Weigh, to the nearest 0,000 1 g, a test portion of approximately 0,25 g of the sample on to a watch glass (7.1.3.1). Transfer the watch glass and test portion to a 250 ml wide-mouth conical flask containing 100 ml of water and 10 ml of su
42、lfuric acid (7.1.2.3). Dissolve the sample, add 3 drops of the diphenylamine indicator solution (7.1.2.2) and titrate with the standardized ammonium cerate solution (7.1.2.1) to a red-violet endpoint. Table 1 Summary of requirements 1) Commercially available analysed reagent is recommended. 2) A pro
43、cedure to prepare ammonium cerium(IV) hexanitrate solution (0,10 mol/l) is given in Annex A. 3) Hazard warning codes are defined in ISO 10349-1:1992, clause 4. 4) This may be prepared from sulfuric acid, = 1,81 g/ml (approximately) (DANGER: ). TestLimitSubclauseInternational Standard in which test m
44、ethod is given Assay Identity Melting point Mixed melting point Infrared spectrum Residue after ignition Heavy metals (as Pb) Iron (Fe) Appearance of solution 99,5 % (m/m) min. 171 C to 175 C Not less than sample or standard Equivalent to Figure 1 0,10 % (m/m) max. 0,002 % (m/m) max. 0,002 % (m/m) m
45、ax. Clear and free from insoluble matter except for a slight flocculence 7.1 7.2.1 7.2.1 7.2.2 7.3 7.4 7.5 7.6 ISO 423 ISO 423 ISO 10349-4 ISO 10349-5 ISO 10349-5 ISO 423 NOTEm/m = mass/mass Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 12:36:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI IS
46、O 423:1994(E) BSI 02-20003 7.1.5 Expression of results The assay, expressed as a percentage by mass of hydroquinone C6H4(OH)2 is given by 5,51cV/m 7.2 Identity tests 7.2.1 Melting point 7.2.1.1 Specifications The melting point shall be from 171 C to 175 C. A mixed melting point shall be from 171 C t
47、o 175 C and shall not be less than either the sample or the standard. 7.2.1.2 Apparatus 7.2.1.2.1 Capillary-tube melting point apparatus, complete with thermometer for the range 100 C to 200 C. 7.2.1.3 Procedure Prepare three capillary tubes containing: a) the sample to be tested; b) a sample known
48、to be hydroquinone; c) a finely ground mixture of a) and b) mixed in equal proportions. Identify the tubes and attach them to the thermometer. Heat the apparatus (7.2.1.2.1) to about 155 C. Insert the thermometer with the samples attached, and thereafter heat so that the temperature rises at a const
49、ant rate of 1 C/min. Note the melting point of each sample as indicated by the first appearance of liquefaction. 7.2.2 Infrared spectrum 7.2.2.1 Specification The infrared absorption curve shall be essentially the same as that of the reference spectrum (Figure 1). This optional recommendation is supplementary to the requirements of 7.2.1. 7.2.2.2 Apparatus 7.2.2.2.1 Test sieve, 63 4m aperture size, conforming to ISO 565. 7.2.2.2.2 Infrared spectrometer, equipped for the 2 4m to 16 4m regions, and accessory equipment for
链接地址:https://www.31doc.com/p-3747219.html