1、May 2017 English price group 8No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 59.140.30!%eBm“2663174www.din.deDIN E
2、N ISO 2420Leather Physical and mechanical tests Determination of apparent density and mass per unit area (ISO 2420:2017);English version EN ISO 2420:2017,English translation of DIN EN ISO 2420:2017-05Leder Physikalische und mechanische Prfungen Bestimmung der Rohdichte und der flchenbezogenen Masse
3、(ISO 2420:2017);Englische Fassung EN ISO 2420:2017,Englische bersetzung von DIN EN ISO 2420:2017-05Cuir Essais physiques et mcaniques Dtermination de la masse volumique apparente et de la masse surfacique (ISO 2420:2017);Version anglaise EN ISO 2420:2017,Traduction anglaise de DIN EN ISO 2420:2017-0
4、5SupersedesDIN EN ISO 2420:200310www.beuth.deDocument comprises 10 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.05.17 DIN EN ISO 2420:2017-05 2 A comma is used as the decimal marker. National foreword This document (EN ISO 2
5、420:2017) has been prepared by Technical Committee IULTCS “International Union of Leather Technologists and Chemists Societies” in collaboration with Technical Committee CEN/TC 289 “Leather” (Secretariat: UNI, Italy). The responsible German body involved in its preparation was DIN-Normenausschuss Ma
6、terialprfung (DIN Standards Committee Materials Testing), Working Committee NA 062-05-51 AA “Requirements and physical test methods of leather and its starting products”. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 2418 DIN EN ISO 2
7、418 ISO 2419 DIN EN ISO 2419 ISO 2589 DIN EN ISO 2589 Amendments This standard differs from DIN EN ISO 2420:2003-10 as follows: a) the determination of mass per unit area has been included in the title and Scope; b) in 4.1 and 6.3, the option to use square test pieces has been included; c) in 8.2, t
8、he calculation of the mass per unit area has been included; d) the standard has been editorially revised. Previous editions DIN 53326: 1944-02 DIN 53327: 1970-12, 1989-09 DIN EN ISO 2420: 2003-10 National Annex NA (informative) Bibliography DIN EN ISO 2418, Leather Chemical, physical and mechanical
9、and fastness tests Sampling location DIN EN ISO 2419, Leather Physical and mechanical tests Sample preparation and conditioning DIN EN ISO 2589, Leather Physical and mechanical tests Determination of thickness EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 2420 February 2017 ICS 59.140.30
10、Supersedes EN ISO 2420:2002English Version Leather - Physical and mechanical tests - Determination of apparent density and mass per unit area (ISO 2420:2017)Cuir - Essais physiques et mcaniques - Dtermination de la masse volumique apparente et de la masse surfacique (ISO 2420:2017) Leder - Physikali
11、sche und mechanische Prfungen - Bestimmung der Rohdichte und der flchenbezogenen Masse (ISO 2420:2017) This European Standard was approved by CEN on 21 December 2016. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Sta
12、ndard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (Engli
13、sh, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, B
14、ulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Swit
15、zerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nation
16、al Members. Ref. No. EN ISO 2420:2017 EEuropean foreword .31 Scope . 52 Normative references 53 Terms and definitions . 54 Principle 55 Apparatus . 56 Sampling and sample preparation 67 Procedure. 67.1 Test conditions 67.2 Measurement of thickness 67.3 Measurement of dimensions .67.4 Measurement of
17、mass . 78 Expression of results 78.1 Apparent density . 78.2 Mass per unit area 89 Test report . 8Contents PageDIN EN ISO 2420:2017-05 EN ISO 2420:2017 (E) 2Foreword .4European foreword This document (EN ISO 2420:2017) has been prepared by Technical Committee IULTCS “International Union of Leather T
18、echnologists and Chemists Societies“ in collaboration with Technical Committee CEN/TC 289 “Leather” the secretariat of which is held by UNI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by August
19、2017, and conflicting national standards shall be withdrawn at the latest by August 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent righ
20、ts. This document supersedes EN ISO 2420:2002. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, For
21、mer Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of I
22、SO 2420:2017 has been approved by CEN as EN ISO 2420:2017 without any modification. DIN EN ISO 2420:2017-05 EN ISO 2420:2017 (E)3 ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Interna
23、tional 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, in liaison with
24、ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, P
25、art 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).Attention is drawn to the possibility that some of
26、the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations
27、 received (see www .iso .org/ patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about
28、ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.ISO 2420 was prepared by the Physical Test Commission of the International Union of Leather Technologists and Chemists Societies (IUP Com
29、mission, IULTCS) in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 289, Leather, the secretariat of which is held by UNI, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).It is based on IUP 5 originally p
30、ublished in J. Soc. Leather Trades Chemists, 42, p. 388, (1958), and declared an official method of the IULTCS in 1959. An updated version was published in J. Soc. Leather Tech. Chem., 82, p. 227, (1998) and a further revision was published in J. Soc. Leather Tech. Chem. 84. p. 313, (2000) and recon
31、firmed as an official method in March 2001.IULTCS, originally formed in 1897, is a world-wide organization of professional leather societies to further the advancement of leather science and technology. IULTCS has three Commissions, which are responsible for establishing international methods for th
32、e sampling and testing of leather. ISO recognizes IULTCS as an international standardizing body for the preparation of test methods for leather.This third edition cancels and replaces the second edition (ISO 2420:2002), which has been technically revised with the following changes: the mass per unit
33、 area has been included; the option to use square test pieces has been included.DIN EN ISO 2420:2017-05 EN ISO 2420:2017 (E) 4 1 ScopeThis document specifies a method for determining the apparent density and the mass per unit area of leather. It is applicable to all leathers.2 Normative referencesTh
34、e following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
35、ISO 2418, Leather Chemical, physical and mechanical and fastness tests Sampling locationISO 2419, Leather Physical and mechanical tests Sample preparation and conditioningISO 2589, Leather Physical and mechanical tests Determination of thicknessEN 15987, Leather Terminology Key definitions for the l
36、eather trade3 Terms and definitionsFor the purposes of this document, the terms and definitions given in EN 15987 apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online br
37、owsing platform: available at h t t p :/ www .iso .org/ obp4 PrincipleThe volume of a test piece is calculated from the area and thickness, treating the test piece as a right-angled circular cylinder or cuboid with a square base. The apparent density is obtained by dividing the mass by the volume. T
38、he mass per unit area is obtained by dividing the mass by the area.5 Apparatus5.1 Press knife, conforming to ISO 2419, the inner wall of which is a circle, approximately 70 mm in diameter, or square, approximately (100 100) mm.5.2 Thickness gauge, as specified in ISO 2589.5.3 Balance, reading to 0,0
39、01 g.5.4 Vernier callipers, reading to 0,01 mm.DIN EN ISO 2420:2017-05 EN ISO 2420:2017 (E)5 6 Sampling and sample preparationSample in accordance with ISO 2418. From the sample, cut three test pieces by applying the press knife (5.1) to the grain surface and condition them in accordance with ISO 24
40、19.If there is a requirement for more than two hides or skins to be tested in one batch, then only one test piece needs to be taken from each hide or skin, provided that the overall total is not less than three test pieces.7 Procedure7.1 Test conditionsCarry out all operations in a standard atmosphe
41、re as specified in ISO 2419.7.2 Measurement of thicknessMeasure the thickness of each test piece in accordance with ISO 2589. Measure the thickness, in millimetres, at three points forming the corners of an equilateral triangle, with each situated approximately 20 mm from the centre of the test piec
42、e. Measure the thickness at the centre of the test piece. Take the arithmetic mean of the four results as the thickness of the test piece, t.NOTE The centre of the test piece and the other points for measurement are estimated by eye.7.3 Measurement of dimensionsFor circular test pieces, measure the
43、diameter using Vernier callipers (5.4) to the nearest 0,05 mm in two directions at right angles to each other on the grain surface and two directions at right angles on the flesh surface. Take the arithmetic mean of the four results as the mean diameter of the test piece, d. Reject any test piece wh
44、ere the diameters on either the grain surface or the flesh surface differ by more than 0,5 mm.For square test pieces, measure the distances AC and BD, where A, B, C and D are the midpoints of each side to within 0,5 mm, using Vernier callipers (5.4) to the nearest 0,05 mm as shown in Figure 1. Measu
45、re the distances on both the grain surface and on the flesh surface. Take the arithmetic mean of the results for the two results of AC, a, and BD, b, respectively. Reject any test piece where the distance measured on the grain surface differs more than 0,5 mm from the distance measured on the flesh
46、surface.Figure 1 Measurement of distances on square test piecesDIN EN ISO 2420:2017-05 EN ISO 2420:2017 (E) 6 7.4 Measurement of massMeasure the mass of the test piece, m, in grams to the nearest 0,001 g.8 Expression of results8.1 Apparent densityFor cylindrical test pieces, the apparent density, Da
47、, in kilograms per cubic metre shall be calculated using Formula (1):Dmtda=1 273 1062,(1)wheret is the mean thickness of the test piece in millimetres (as obtained in 7.2);d is the mean diameter of the test piece in millimetres (as obtained in 7.3);m is the mass of the test piece in grams (as obtain
48、ed in 7.4).NOTE 1 Formula (1) assumes that the sample is a circular cylinder whose volume, V, in cubic millimetres is given by:Vdt=pi24which is simplified to dt21 273,The factor 1,273 continues through to the final calculation.For cuboid test pieces with a square base, the apparent density, Da, in kilograms per cubic metre shall be calculated using Formula (2):Dmtaba=106(2)wheret is the mean thickness of the test piece in
