ISO INTERNATIONAL STANDARD 4593 Second edition 1993-11-15 Plastics Film and sheeting Determination of thickness by mechanical scanning Plastiques Film et feuille -Determination de I'épaisseur par examen mécanique So Referencenumber ISO 4593:1993(E) No reproduction or networking permited without license from IHS Not for Resale ISO4593:1993(E) Foreword ISO (the International Organization for Standardization) is a worldwide of 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, 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. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 4593 was prepared by Technical Committee ISO/TC 61, Plastics, Sub-Committee SC 11, Products. This second edition cancels sand replaces the first edition (ISO 4593:1979), which has been technically revised. ISO 1993 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without per- mission in writing from the publisher. International Organization for Standardization Case Postale 56 . CH-1211 Geneve 20 · Switzerland Printed in Switzerland !! d without license from IHS Not for Resale INTERNATIONAL STANDARD ISO 4593:1993(E) Plastics Film and sheeting Determination of thickness by mechanical scanning Scope 2.1.2 In the case of plane/radiused measuring sur- faces, the diameter of the plane lower surface shall This International Standard specifies a method for the not be less than 5 mm and the radius of curvature of determination of the thickness of a sample of plastics the upper surface shall be 15 mm to 50 mm. The film or sheeting by mechanical scanning. force applied to the radiused face shall be 0,1 N to 0,5 N. The method is not suitable for use with embossed film or sheeting. NOTE 2 Transmission of the measured values may be performed, for example, mechanically (by micrometer), op tically (by mirror instrument) or electronically (inductively). 2 Apparatus 2.1 Thickness-measuring 3 Test specimens device, capable of measuring to the following accuracies: Cut test specimens, about 100 mm wide, across the whole width of the sample. When required, take 1 μm (see note 1); specimens at positions approximately 1 m apart in the longitudinal direction of the sample. The specimens above 100 μm and up to and including 250 μm to shallcontainnocreases exceptthosenecessaryfor folding the film for presentation or packaging pur- anaccuracy of 2μm; poses.The specimens shall containnootherdefects. -above 250 μm to an accuracy of 3 μm. 4 Procedure NOTE 1 Where the above is not adequate and a higher accuracy is required,thismethod should not be appliedbut a more suitable measuring device or method selected.The 4.1 Condition the specimens for at least 1 h at determination of gravimetric thickness is described in 23 °C ± 2 °C. For moisture-sensitive films, the condi- iso 4591:1992, Plastics Film and sheeting - Determi- tioning time and atmosphere shall be as stated in the nation of average thickness of a sample, and average thick- specification for the material under test or as specified nessand yield of a roll, by gravimetric techniques between buyer and seller. gravimetricthickness 4.2 Ensure that the specimens and the faces of the The measuring surfaces of the device shali comprise a plane lower face and either a plane or radiused up- measuring device (2.1) are free from contamination