1、March 2017 English price group 7No 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 85.060!%bVo“2635176www.din.deDIN IS
2、O 5630-7Paper and board Accelerated ageing Part 7: Exposure to light (ISO 56307:2014),English translation of DIN ISO 5630-7:2017-03Papier und Pappe Beschleunigte Alterung Teil 7: Einwirkung von Licht (ISO 56307:2014),Englische bersetzung von DIN ISO 5630-7:2017-03Papier et carton Vieillissement accl
3、r Partie 7: Exposition la lumire (ISO 56307:2014),Traduction anglaise de DIN ISO 5630-7:2017-03www.beuth.deDocument comprises 10 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.02.17 A comma is used as the decimal marker. Conte
4、nts Page National foreword 3 National Annex NA (informative) Bibliography 3 Introduction 41 Scope . 52 Normative references 53 Principle 54 Apparatus . 55 Sampling 66 Conditioning 67 Preparation of test pieces for ageing . 68 Procedure. 69 Calculation 710 Test report . 7Annex A (informative) Interpr
5、etation and limitations of ageing tests 9Bibliography . 10.DIN ISO 5630-7:2017-03 2 National foreword This document (ISO 5630-7:2014) has been prepared by Technical Committee ISO/TC 6/SC 2 “Test methods and quality specifications for paper and board” (Secretariat: SIS, Sweden). The responsible Germa
6、n body involved in its preparation was DIN-Normenausschuss Papier, Pappe und Faserstoff (DIN Standards Committee Paper, Board and Pulps), Working Committee NA 074-02-03 AA Physikalischtechnische Prfverfahren fr Papier und Pappe. Attention is drawn to the possibility that some of the elements of this
7、 document may be the subject of patent rights. DIN shall not be held responsible for identifying any or all such patent rights. DIN ISO 5630 consists of the following parts, under the general title Paper and board Accelerated ageing: Part 1: Dry heat treatment at 105 C Part 3: Moist heat treatment a
8、t 80 C and 65 % relative humidity Part 4: Dry heat treatment at 120 or 150 C Part 5: Exposure to elevated temperature at 100 C Part 6: Exposure to atmospheric pollution (nitrogen dioxide) Part 7: Exposure to light NOTE ISO 5630-2, Paper and board Accelerated aging Part 2: Moist heat treatment at 90
9、C and 25 % relative humidity was withdrawn by ISO in 1992. Thus, there is no corresponding Part 2 as a DIN ISO Standard. The DIN Standard corresponding to the International Standard referred to in this document is as follows: ISO 186 DIN EN ISO 186 National Annex NA (informative) Bibliography DIN EN
10、 ISO 186, Paper and board Sampling to determine average quality DIN ISO 5630-7:2017-03 3 IntroductionExposure of paper or board to a hostile environment, such as some type of radiation, elevated temperature, or chemical pollutant over a period of hours or days can provide information concerning the
11、natural changes that can occur in the material over a period of years.This test method for accelerated ageing by exposure of paper to an elevated light flux has its origins in the extensive ASTM2research program which developed experimental procedures and studied a range of printing and writing pape
12、rs. The light irradiance specified in this part of ISO 5630 is much lower than that recommended by the ASTM study which is considered too high and requires expensive and hazardous equipment.To get a full understanding of the stability of paper to long-term natural ageing effects, a combination of te
13、st methods for accelerated ageing can be used. Application of accelerated ageing tests assumes that the changes that occur under harsher than normal conditions have a strong positive correlation with those occurring under “normal” conditions.Paper and board Accelerated ageing Part 7: Exposure to lig
14、htDIN ISO 5630-7:2017-03 4 1 ScopeThis part of ISO 5630 specifies a method for accelerating the ageing of paper and board through exposure to an elevated light irradiance and for assessing the effect of ageing on optical properties for the purpose of predicting stability to long-term natural ageing
15、that occurs due to exposure to light. It is applicable to all types of paper and board whose surface is white or near white.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references,
16、 only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 186, Paper and board Sampling to determine average qualityISO 187, Paper, board and pulps Standard atmosphere for conditioning and testing and procedure for m
17、onitoring the atmosphere and conditioning of samplesISO 2470-1, Paper, board and pulps Measurement of diffuse blue reflectance factor Part 1: Indoor daylight conditions (ISO brightness)ISO 5631-1, Paper and board Determination of colour by diffuse reflectance Part 1: Indoor daylight conditions (C/2)
18、3 PrincipleSheets of paper are aged at an accelerated rate by exposing them to an elevated light irradiance. The elevated irradiance accelerates changes in the optical properties which occur when paper is exposed to “normal” light levels over an extended period. By comparing diffuse blue reflectance
19、 factor (ISO brightness) and the b* CIELab colour coordinate before and after ageing, a measure of the stability of the optical properties of the paper when exposed to light is obtained.4 Apparatus4.1 Light source, producing an even irradiance (total irradiance) to all test surfaces of 20 W/m2 1 W/m
20、2in the wavelength range 290 nm to 800 nm with a UV component of 1,0 W/m2 0,1 W/m2. The ratio of the irradiance in the wavelength range 400 nm to 600 nm to that in the range 600 nm to 800 nm shall be 1,0 to 1,5 with all wavelengths over the range 400 nm to 700 nm present in the radiation.The uniform
21、ity of the total irradiance shall be such that it does not vary by more than 1 W/m2on any portion of the test surface of the specimen. If the light delivered by the source includes wavelengths below 300 nm, these shall be removed by the use of a suitable glass filter.The total irradiance of the ligh
22、t source at the specimen surface shall be checked at regular intervals to maintain it within a range of 1 W/m2of its nominal value (value when first tested or first used) with a UV component maintained within 0,1 W/m2. If the irradiance is outside either of these ranges, the lamp(s) shall be replace
23、d.DIN ISO 5630-7:2017-03 5 4.2 Light chamber, of a size sufficient to mount the number of test pieces required for testing (Clause 8) in such a way that all of the surface area on one side of each specimen is exposed uniformly to the specified irradiance (4.1).4.3 System for controlling the temperat
24、ure of the surface of the test pieces, that keeps the surface temperature of the test pieces below 26 C when exposed to the light used to age them. For example, a system for blowing air that meets the specifications of the atmosphere used to condition the test specimens (Clause 6), over the specimen
25、s at a sufficiently high rate.5 SamplingOnly handle the paper samples with clean cotton gloves. The samples shall be kept in the dark except during sampling, while being placed and exposed in the light chamber and during testing.If the average quality of a lot is to be determined, sampling shall be
26、carried out in accordance with ISO 186. If another type of sample is to be tested, make sure that the sheets or specimens taken are representative of the sample received. Select sufficient specimens or sheets of adequate size for testing brightness and colour before and after ageing (Clause 8).Unles
27、s the two sides of the specimens or sheets are easily distinguished, mark the same side of each specimen/sheet so that the ageing results can be associated with a particular side.6 ConditioningKeep the specimens or sheets in the dark, condition them in accordance with ISO 187 immediately prior to in
28、itial testing of optical properties.7 Preparation of test pieces for ageingCarry out the preparation of the test pieces in the same atmosphere as used for conditioning (Clause 6).Prepare sufficient test pieces for testing of optical properties (Clause 8). The test piece size and preparation shall co
29、nform with the requirements of ISO 2470-1, except that two sets of test pieces shall be prepared, one for testing the optical properties and the other for the backing pad which shall be used for testing of all test pieces, both unaged and aged, i.e. the backing pad shall not change. As long as the p
30、ad meets the optical requirements of ISO 2470-1, the number of the test pieces in the pad can be less than ten.8 ProcedureDetermine the diffuse blue reflectance factor (ISO brightness) in accordance with ISO 2470-1 and the b* CIELab colour coordinate in accordance with ISO 5631-1, of the top side of
31、 the unaged test pieces in the same atmosphere as used for conditioning (Clause 6), except that the test pieces being tested shall not be part of the backing stack. Take note of the positions of testing by some appropriate means as the same areas shall be tested after accelerated ageing. Retain the
32、stack of test pieces used as the backing for the optical tests on the unaged material for testing the test pieces after aging.Immediately after testing the test pieces, mount them in the light chamber (4.2), such that the top surface of each test piece will be exposed to the same even light flux (4.
33、1). Mount the test pieces, such that they do not touch the chamber walls (4.2). The light chamber shall be kept in the same atmosphere as used for conditioning (Clause 6) during mounting and exposure of the test pieces.Immediately after mounting, expose the test pieces to the specified light flux fo
34、r (120 0,5) h. Ensure that the temperature at the surface of each test piece is kept below 26 C (and above 22 C). A lower irradiance than that specified in 4.1 may be used as long as the ratio between the total and UV components is maintained and all other specifications of the irradiance are met. I
35、n this case, it may be desirable to DIN ISO 5630-7:2017-03 6 use a longer exposure time. The deviation from the specified conditions shall be reported. The results obtained cannot be considered to conform with the requirements of this part of ISO 5630.Do not insert additional test pieces into or rem
36、ove test pieces from the light chamber during the period of exposure.Immediately after ageing, determine the diffuse blue reflectance factor (ISO brightness), in accordance with ISO 2470-1, and the b* CIELab colour coordinate, in accordance with ISO 5631-1, of the aged test specimens except that the
37、 same backing pad used for testing of unaged test pieces shall be used for testing each of the aged test pieces. Test an area of each test piece as close as possible to that tested prior to ageing such as to produce matched pairs of results.If required, repeat the testing for the other side of the t
38、est pieces; formation of a backing pad, testing of unaged test pieces, ageing of the test pieces, and testing of the aged test pieces.If there is sufficient room in the test chamber, testing of both sides of the unaged test pieces may be carried out prior to ageing of the test pieces and then both t
39、he top side and reverse side aged in the ageing chamber at the same time.9 CalculationCalculate the change in diffuse blue reflectance factor (ISO brightness) and the change in b* CIELab colour coordinate for matched pairs of results, pre-aged and aged, for the top side as shown below.Calculate the
40、change in ISO brightness, to the nearest %, with Formula (1):RRRR=()121100(1)whereR is the change in diffuse blue reflectance factor (ISO brightness), as a percentage;R1is the diffuse blue reflectance factor (ISO brightness) before ageing;R2is the diffuse blue reflectance factor (ISO brightness) aft
41、er ageing.Calculate the change in b* CIELab colour coordinate, to three significant figures, with Formula (2):(*)* *bbb=21(2)where(b*) is the change in b* CIELab colour coordinate;b*1is the b* CIELab colour coordinate before ageing;b*2is the b* CIELab colour coordinate after ageing.Calculate the mea
42、n change in diffuse blue reflectance factor (ISO brightness) to the nearest 1 %, and the mean change in the b* CIELab colour coordinate to three significant figures, and calculate the standard deviation for each. If required, calculate these for the reverse side as well.10 Test reportThe test report
43、 shall include the following information:a) a reference to this part of ISO 5630 (i.e. ISO 5630-7);DIN ISO 5630-7:2017-03 7 b) all information necessary for complete identification of the sample;c) the date and place of testing;d) the temperature and relative humidity of the atmosphere used to condi
44、tion the samples;e) the number of tests carried out for each sample and side;f) the mean values of the change in diffuse blue reflectance factor (ISO brightness) and the change in the b* CIELab colour coordinate, and the corresponding standard deviations. If required, report these values both sides
45、of the samples;g) when the total irradiance is less than that specified in 4.1, a statement on the level of irradiance used and the time of exposure. In this case, the results cannot be considered to have been obtained using this part of the International Standard.k) any deviations from the Internat
46、ional Standards used, and any circumstances and influence which might have affected the test results.DIN ISO 5630-7:2017-03 8 Annex A (informative) Interpretation and limitations of ageing testsA.1 Interpretation of test resultsIt is very important to note that what is stable paper for one user can
47、be unstable for another. Therefore, the limits of acceptability (the points at which a paper is no longer useful for its intended purpose) is to be defined by end-users. It is only with such information in hand that an approximate definition of the long-term stability of the optical properties of a specific paper can be made.NOTE If all that is desired is legibility of a printed text, paper can become significantly yellowed and still meet the requirements of the end user.A.2 Limitations of light ageing testIt should be mentioned that natural ageing is various
