1、BSI Standards PublicationBS ISO 23900-3:2015Pigments and extenders Methods of dispersion andassessment of dispersibility inplasticsPart 3: Determination of colouristicproperties and ease of dispersion of blackand colour pigments in polyethylene bytwo-roll millingBS ISO 23900-3:2015 BRITISH STANDARDN
2、ational forewordThis British Standard is the UK implementation of ISO 23900-3:2015.The UK participation in its preparation was entrusted to TechnicalCommittee STI/1, Pigments.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not pu
3、rport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 86263 2ICS 87.060.10Compliance with a British Standard cannot confer immunity fromlegal obligatio
4、ns.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 May 2015.Amendments issued since publicationDate Text affectedBS ISO 23900-3:2015 ISO 2015Pigments and extenders Methods of dispersion and assessment of dispersibility in plastics Part 3: D
5、etermination of colouristic properties and ease of dispersion of black and colour pigments in polyethylene by two-roll millingPigments et matires de charge Mthodes de dispersion et valuation de laptitude la dispersion dans les plastiques Partie 3: Dtermination des proprits colorimtriques et de la fa
6、cilit de dispersion des pigments noirs et colors dans le polythylne par calandrage sur bicylindreINTERNATIONAL STANDARDISO23900-3First edition2015-05-01Reference numberISO 23900-3:2015(E)BS ISO 23900-3:2015ISO 23900-3:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rig
7、hts reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from e
8、ither ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 23900-3:2015ISO 23900-3:2015(E)Foreword iv1 Scope .
9、12 Normative references 13 Terms and definitions . 14 Principle 25 Materials . 25.1 Materials for method A 25.1.1 Test medium 25.1.2 Titanium dioxide pigment . 25.2 Materials for method B 25.2.1 Test medium 25.2.2 Titanium dioxide pigment . 26 Apparatus . 27 Sampling 38 Procedure. 38.1 Testing of co
10、louristic properties in white reduction 38.1.1 Preparation of the mixtures . 38.1.2 Two-roll milling 38.1.3 Pressing . 48.1.4 Photometric measurement . 48.2 Testing of ease of dispersion . 48.2.1 Preparation of the test samples 48.2.2 Pressing and photometric measurement . 49 Evaluation 410 Test rep
11、ort . 511 Precision . 5Bibliography 6 ISO 2015 All rights reserved iiiContents PageBS ISO 23900-3:2015ISO 23900-3:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International St
12、andards 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
13、 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, Part 1. In
14、 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 the elements
15、 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 received (s
16、ee 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 ISOs adherence
17、to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information .The committee responsible for this document is ISO/TC 256, Pigments, dyestuffs and extenders.ISO 23900 consists of the following parts, under the general title Pigments and exte
18、nders Methods of dispersion and assessment of dispersibility in plastics: Part 1: General introduction Part 2: Determination of colouristic properties and ease of dispersion in plasticized polyvinyl chloride by two-roll milling Part 3: Determination of colouristic properties and ease of dispersion o
19、f black and colour pigments in polyethylene by two-roll milling Part 4: Determination of colouristic properties and ease of dispersion of white pigments in polyethylene by two-roll milling Part 5: Determination by filter pressure value test Part 6: Determination by film testiv ISO 2015 All rights re
20、servedBS ISO 23900-3:2015Pigments and extenders Methods of dispersion and assessment of dispersibility in plastics Part 3: Determination of colouristic properties and ease of dispersion of black and colour pigments in polyethylene by two-roll milling1 ScopeThis part of ISO 23900 specifies a method o
21、f determining in polyethylene (PE) the colouristic properties of a test pigment relative to a standard, and the ease of dispersion DHPEof pigments from the differences in colour strength on dispersing colouring materials under various conditions.Method A is appropriate for use with organic powder pi
22、gments and carbon black pigments in powder form, many of which are subject to compaction (reagglomeration under pressure), for inorganic pigments in powder form and for pigment preparations in powder or flake form.Method B is appropriate for testing pigments and pigment preparations in granular form
23、 and for inorganic pigments in any form.The ease of dispersion determined in this way is valid only for the dispersion equipment, dispersion conditions and dispersion medium being used. The use of test conditions differing from those specified may give different results; this applies both to the abs
24、olute magnitude and to the relation between values of the ease of dispersion of various pigments. The subscript DHPEis therefore used to designate the value obtained as specified in this part of ISO 23900.2 Normative referencesThe following documents, in whole or in part, are normatively referenced
25、in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 787-24:1985, General methods of test for pigments and extenders Part 24: Dete
26、rmination of relative tinting strength of coloured pigments and relative scattering power of white pigments Photometric methodsISO 15528, Paints, varnishes and raw materials for paints and varnishes SamplingISO 18314-11), Analytical colorimetry Part 1: Practical colour measurement3 Terms and definit
27、ionsFor the purposes of this document, the following terms and definitions apply.1) To be published.INTERNATIONAL STANDARD ISO 23900-3:2015(E) ISO 2015 All rights reserved 1BS ISO 23900-3:2015ISO 23900-3:2015(E)3.1ease of dispersionDHPEmeasure of the rate at which or the degree to which a pigment or
28、 extender achieves a given level of dispersion when dispersed in a plastics materialNote 1 to entry: The DHPEis derived from the increase in colour strength achieved by two-roll milling as specified in 8.2, relative to the colour strength achieved as specified in 8.1.4 PrincipleUsing a two-roll mill
29、, the pigment under test is dispersed at an appropriate temperature in the polymer. The cooled milled sheet obtained in this way is then subjected to the higher shearing forces resulting from two-roll milling at a narrower gap width. The resulting increase in colour strength (see EN 12877-1) is a me
30、asure of the ease of dispersion DHPE.5 Materials5.1 Materials for method A5.1.1 Test mediumPolyethylene, in powder or flake form; of a type and grade to be agreed between the interested parties.NOTE Where HDPE is used, a phenolic antioxidant can be used to facilitate processing.5.1.2 Titanium dioxid
31、e pigmentEasily dispersing powder grade of a type recommended for use in polyethylene.5.2 Materials for method B5.2.1 Test mediumPolyethylene, in granular form; of a type and grade to be agreed between the interested parties.NOTE Where HDPE is used, a phenolic antioxidant can be used to facilitate p
32、rocessing.5.2.2 Titanium dioxide pigmentAs in 5.1.2 or as a well dispersed polyethylene masterbatch.6 Apparatus6.1 Two-roll mill. Equipped with heating facilities and having rollers adjustable for spacing. The roll diameter shall be between 80 mm and 200 mm, and the ratio of the speeds of rotation o
33、f the two rollers shall be between 1:1,1 and 1:1,2.NOTE It has been found that comparable results on different two-roll mills can be obtained under the following conditions ratio of roller diameters of the two machines: between 1:1 and 1:1,5; ratio of peripheral speeds: between 1:1 and 1:1,1; Hk(ban
34、k) to Hs(gap width) such as Hk/Hs 20.2 ISO 2015 All rights reservedBS ISO 23900-3:2015ISO 23900-3:2015(E)If smaller roller sets are used (roller diameter e.g. 80 mm), the settings of the thickness of the milled sheet from 0,4 mm to 0,5 mm with the recommended conditions of similarity can lead to dif
35、ficulties with regard to the requirement for a rolling bank.6.2 Plate press. Provided with heating facilities and, advantageously, also with cooling facilities.6.3 Photometer.7 SamplingRepresentative samples of the colouring materials to be tested shall be taken as specified in ISO 15528.8 Procedure
36、8.1 Testing of colouristic properties in white reduction8.1.1 Preparation of the mixtures8.1.1.1 Preparation of the mixture for method AIn a plastic beaker pre-blend gently 100 parts of polyethylene powder, 1,0 parts titanium dioxide pigment (5,0 parts in the case of carbon black) and where appropri
37、ate 0,1 parts antioxidant. Add 0,1 parts of carbon black or organic test pigment or 0,2 parts to 0,5 parts of inorganic test pigment according to type. Mix using a spatula so that no test pigment remains on the beaker walls.NOTE It can be advantageous to prepare a large quantity of a homogeneous pre
38、-blend of polymer powder, antioxidant and titanium dioxide pigment for example by mixing for 5 min in a laboratory high speed mixer at 1 800 min-1followed by extrusion and grinding into a suitably fine form in order to improve reproducibility.8.1.1.2 Preparation of the mixture for method BPrepare a
39、mixture of 100 parts of PE granulate (5.2.1) with 1,0 parts titanium dioxide pigment (5,0 parts in the case of carbon black) or an equivalent quantity of titanium dioxide masterbatch (5.2.2) in a plastic beaker or other suitable container.8.1.2 Two-roll milling8.1.2.1 Method AThe mixture is added to
40、 the rotating mill rolls which have been brought to a defined temperature, previously established as allowing easy handling of the polymer on the mill. Temperatures of between 140 C and 160 C have been found suitable for most types of polymer.With a gap width set at 0,4 mm to 0,5 mm a sheet is forme
41、d within approximately 1 min in such a way that the whole of the material forms a continuous sheet on the front roll. Any material falling through the nip shall be returned quickly and carefully from the tray to the rotating mill rolls. The quantity of mixture to be used shall be such that a continu
42、ously rotation bead is formed in the nip, once the sheet has been formed.NOTE A quantity of test mixture based on 100 g polymer is generally adequate for most two-roll mills. It can be increased according to the size of the mill in order to facilitate handling.The dispersion of the pigment is obtain
43、ed by cutting and folding of the sheet, once formed, every 30 s while milling with a gap width set at 0,5 mm for a total of 200 rotations of the rolls, counting from the point at which the mixture is added to the mill. According to the diameter of the rolls of the machine being used (see 6.1) the du
44、ration of milling shall not be less than 5 min but shall not exceed 10 min. ISO 2015 All rights reserved 3BS ISO 23900-3:2015ISO 23900-3:2015(E)8.1.2.2 Method BPlace the mixture on the static, previously heated two-roll mill using the gap width and temperatures as described in 8.1.2.1 and allow to p
45、re-heat for 1 min. Start the two-roll mill and prepare a mill sheet in about 1 min. Add the test pigment or pigment preparation slowly and evenly to the rotating sheet across the width of the mill. The dispersion of the pigment then proceeds as in 8.1.2.1.After each milling operation the rolls shall
46、 be cleaned.8.1.3 PressingFor photometric measurement it is advantageous to prepare specimens with a high surface gloss and quality.Such specimens may be obtained by pressing the sheets in a plate press for no longer than 2 min at a temperature between 160 C and 170 C maximum, between high gloss chr
47、ome steel plates using a spacer frame of 1 mm thickness. The pressed sheets shall be cooled rapidly to room temperature.8.1.4 Photometric measurementThe colour strength and colouristic properties of the test specimens prepared as specified in 8.1.2 and 8.1.3 shall be measured as specified in ISO 183
48、14-1. These values shall be used to determine the colour strength as specified in ISO 787-24:1985, 8.1 and Clause 9 for the purposes of the calculation of DHPE.8.2 Testing of ease of dispersion8.2.1 Preparation of the test samplesThe roll gap of the mill is reduced to 0,3 mm and one half of the shee
49、t prepared under 8.1.2 is returned to the rollers maintained at the same temperature as used in 8.1.2 at 25 min1. Milling is continued for 200 revolutions of the rolls with cutting and folding every 30 s. The sheet is then removed and cooled between metal plates.This procedure is carried out for each sheet containing the test pigments.After each milling operation the rolls shall be cleaned.8.2.2 Pressing and photometric measurementPressing and photometric measurement are carried out as specified in 8.1.3 and 8.
