© ISO 2016 Tissue paper and tissue products — Part 6 Determination of grammage Papier tissue et produits tissue — Partie 6 Détermination du grammage INTERNATIONAL STANDARD ISO 12625 6 Second edition 2[.]
INTERNATIONAL STANDARD ISO 12625-6 Second edition 2016-12-01 Tissue paper and tissue products — Part 6: Determination of grammage Papier tissue et produits tissue — Partie 6: Détermination du grammage Reference number ISO 12625-6:2016(E) I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n © ISO 2016 ISO 12625-6:2016(E) COPYRIGHT PROTECTED DOCUMENT © ISO 2016, Published in Switzerland All rights reserved Unless otherwise specified, no part o f 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 either ISO at the address below or ISO’s member body in the country o f the requester ISO copyright o ffice Ch de Blandonnet • CP 401 CH-1214 Vernier, Geneva, Switzerland Tel +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n ISO 12625-6:2016(E) Contents Page Foreword iv Scope Normative references Terms and definitions Principle Apparatus Sampling Conditioning Preparation of test pieces 8.1 8.2 8.3 General Cutting of the test pieces 8.2.1 General 8.2.2 Size of test pieces 8.2.3 Number of test pieces Uncut finished products 8.3.1 General 8.3.2 Size of test pieces 8.3.3 Number of test pieces Procedure 10 Calculation 9.1 9.2 Determination of the mass of the test pieces Determination of the area of the test pieces 10.1 General 10.2 Mean and standard deviation of grammage 11 Test report Annex A (informative) Precision Bibliography 10 © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n iii ISO 12625-6:2016(E) Foreword I SO (the I nternational O rganiz ation for Standardiz ation) is a worldwide federation of national s tandards bodies (ISO member bodies) The work o f preparing International Standards is normally carried out through ISO technical committees Each member body interested in a subject for which a technical committee has b een es tablished has the right to b e represented on that committee I nternational organi zation s , governmental and non- governmental, in liaison with I SO, al so take p ar t in the work ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters o f elec trotechnical s tandardi z ation T he procedures used to develop this cument and those intended for its fur ther maintenance are describ ed in the I SO/I E C D irec tives , Par t I n p ar ticu lar the different approval criteria needed for the di fferent types o f ISO documents should be noted This document was dra fted in accordance with the editorial ru les of the I SO/I E C D irec tives , Par t (see www iso org/direc tives) Attention is drawn to the possibility that some o f the elements o f this document may be the subject o f patent rights ISO shall not be held responsible for identi fying any or all such patent rights Details o f any patent rights identified during the development o f the document will be in the Introduction and/or on the I SO l is t of p atent declarations received (see www iso org/p atents) Any trade name used in this document is in formation given for the convenience o f users and does not cons titute an endors ement For an explanation on the meaning o f ISO specific terms and expressions related to formity assessment, as well as information about I SO ’s adherence to the World Trade O rganization ( WTO) principles in the Technical B arriers to Trade (TB T ) see the following URL: www.iso.org/iso/foreword html This document was prepared by the European Committee Standardization (CEN) Technical Committee C E N/ TC 172 , Pulp, paper and board, in col lab oration with I SO Technical C ommittee TC , Paper, board and pulps, Sub committee SC , Test methods and quality specifications for paper and board, in accordance with the Agreement on technical co op eration b etween I S O and C E N ( Vienna Agreement) This second edition cancels and replaces the first edition (ISO 12625-6:2005), which has been technically revised with the following changes: a) a new s ub clause, , has b een added; b) f c) in Annex A, the precis ion data has b een up dated; ormulae were added to clari fy C lause 10 ; d) this document has been editorially updated A lis t of al l p ar ts in the I SO 62 series can b e found on the I SO web s ite iv I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n INTERNATIONAL STANDARD ISO 12625-6:2016(E) Tissue paper and tissue products — Part 6: Determination of grammage Scope T h i s c ument s p e ci fie s a te s t me tho d products for the de term i nation o f gram mage o f ti s s ue p ap er and ti s s ue Normative references T he fol lowi ng c u ments are re ferre d to i n the tex t i n s uch a way th at s ome or a l l o f thei r content s titute s re qu i rements o f th i s c u ment For date d re ference s , on ly the e d ition cite d app l ie s For u ndate d re ference s , the late s t e d ition o f the re ference d c ument (i nclud i ng a ny amend ments) appl ie s ISO 186, Paper and board — Sampling to determine average quality ISO 187, Paper, board and pulps — Standard atmosphere for conditioning and testing and procedure for monitoring the atmosphere and conditioning o f samples Terms and definitions For the pu r p o s e s o f th i s c u ment, the fol lowi ng term s and defi n ition s apply ISO and IEC maintain terminological databases for use in standardization at the following addresses: — IEC Electropedia: available at http://www.electropedia.org/ — ISO Online browsing platform: available at http://www.iso.org/obp 3.1 grammage g mas s o f a un it a re a o f ti s s ue p ap er or ti s s ue pro duc t a s de term i ne d b y the pro ce du re i n th i s c u ment N o te to entr y: Gra m m age i s e xp re s s e d i n gra m s p er s qu a re me tre ( g/m ) Principle The mass and area of a test piece or test pieces of either a tissue paper or a tissue product is measured and the gra m mage i s ca lc u late d a s the ma s s p er u n it a re a o f the te s t pie ce s ta ken For fi ni s he d p ap er pro duc ts , the gram mage may a l s o b e c a lc u late d from the mas s a nd are a o f a s p e c i fie d nu mb er o f the fi n i s he d ti s s ue pro duc t item s P re ci s ion data a re ava i l able i n © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n Annex A ISO 62 -6: 01 6(E) Apparatus General T he b a la nce sh a l l b e place d on a hori z onta l s u r face fre e from e xterna l ly i nduce d vibration s Cutting device T he c utti ng device sh a l l b e c ap able o f rep e ate d ly cle an ly c utti ng te s t pie ce s o f the s ame nom i na l s i z e, who s e are a fa l l s with i n ±1 , % o f a known are a T h i s sh a l l b e che cke d fre quently b y me as u rement a nd , for provide d that the ab ove acc u rac y i s attai ne d, the me an are a ob tai ne d i n the s e che cks s l l b e u s e d calcu lating gram mage With cer ta i n typ e s o f ti s s ue p ap er and ti s s ue pro duc t, it wi l l be fou nd, a fter c arr yi ng out th i s de term i nation o f are a, that te s t pie ce s c an no t b e c ut with the acc urac y j u s t defi ne d I n s uch i n s ta nce s , the are a o f ever y te s t pie ce sha l l b e de term i ne d i nd ividua l ly Balance T he device to de term i ne the b a la nce sh a l l have a me a s uri ng acc urac y o f , 01 g Length measurement device T he leng th me as u rement device sh a l l b e a r u ler, an ele c tron ic d igita l r u ler, a s c a n ner or a ny o ther device with a m i n i mu m me as u ri ng acc u rac y o f , m m Sampling I f the tes ts are b eing made to evaluate a lot, the s ample shal l b e selec ted in accordance with I SO 18 I f the te s ts a re b ei ng made on ano ther typ e o f s ample, repre s entative o f the s ample E ach te s t pie ce sh a l l b e ma ke fre e from s u re that a l l s p e ci men s p er foration s and fau lts ta ken a re no t norma l ly in herent in the tis s ue Conditioning C ond ition the s amples accord i ng to I S O and ke ep them i n the s tandard atmo s phere th roughout the te s t C onditioning shal l b e done prior to the prep aration of tes t pieces 8.1 Preparation of test pieces General Tes t pieces shal l b e free from areas containing creases , dir t or vis ible damage Tes t pieces shal l b e made of either areas cut from s p ecimens of tis s ue p ap er or tis s ue pro duc ts (see ) , or made of whole fi n i she d pro duc ts (s e e ) I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n ISO 62 -6: 01 6(E) 8.2 8.2 Cutting of the test pieces General In the case where test pieces are cut from specimens of tissue paper or tissue products, the test sheet or s tack o f s up eri mp o s e d te s t s he e ts c a n b e place d b e twe en two s upp or ti ng s he e ts o f p ap er, s uch a s o ffice cop y p ap er, i n order to ob tai n te s t pie ce s with cle an c ut e dge s a nd d i men s ion s o f the acc u rac y s p e ci fie d 8.2 Size of test pieces Si nce ti s s ue p ap er a nd ti s s ue pro duc ts va r y gre atly i n d i men s ion s , it i s on ly p o s s ible to give genera l guidance regarding the dimension of the test piece or test pieces The minimum area of an individual test piece shall be at least 100 cm2 be composed of several smaller pieces 8.2 O ne te s t pie ce may, i f ne ce s s ar y, Number of test pieces Using the cutting device (5.2), cut at least 10 test pieces The mass of a minimum area of 000 cm2 shall be determined, and convenient larger areas shall be taken in compliance with the provisions of this document 8.3 Uncut finished products 8.3 General I n the c a s e where te s t pie ce s are comp o s e d o f fi n i she d ti s s ue pro duc ts , te s t pie ce s sh a l l l ie un folde d a nd flat with no ten s ion appl ie d I f a s c an ner i s u s e d for th i s me as u rement, en s u re that the s c an ner- cover i s s u fficient i n s i z e to c au s e the item to l ie flat If a ruler is used, it shall be of dimensions larger than the test piece 8.3 Size of test pieces Si nce ti s s ue p ap er a nd ti s s ue pro duc ts va r y gre atly i n d i men s ion s , it i s on ly p o s s ible to give genera l guidance regarding the dimension of the test piece or test pieces Using a measuring device (5.4) as described, the minimum area of an individual test piece shall be at least 100 cm2 f f O ne te s t pie ce may, i 8.3 ne ce s s a r y, b e comp o s e d o s evera l s ma l ler pie ce s Number of test pieces The minimum number of test pieces shall be 10 The mass of a minimum area of 000 cm shall be determined, and convenient larger areas shall be taken in compliance with the provisions of this document T he 10 or more te s t pie ce s (fi n i she d pro duc t item s) sha l l b e s ele c te d from the s a mple i n a random man ner s o as to repre s ent va ri ation i n s i ze and ma s s o f the fi n i s he d pro duc t item pre s ent i n the s ample I n a ny c as e, s e quenti a l fi n i s he d pro duc t u n its s l l never b e te s te d, excep t i n c as e s where the s a mple i s ver y l i m ite d i n qua ntity © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n ISO 62 -6: 01 6(E) Procedure 9.1 Determination of the mass of the test pieces Determine the mass of each test piece on the balance (5.3) to the nearest 0,001 g It is recommended, especially when dealing with small test pieces, that touching the test pieces with bare hands is avoided I f the standard deviation is not needed, the total mass o f all 10 or more test pieces may be determined by weighing all test pieces together Any deviation from the procedure described above shall be explicitly mentioned in the test report 9.2 Determination of the area of the test pieces 9.2 When test pieces have been cut to specified dimensions as described in 8.2, determine the area of each individual test piece For the determination o f grammage on finished paper products, the total area shall be measured to an accuracy o f better than % using a measuring device (5.4) as described 9.2 When the test pieces are measured, they shall lie un folded and flat with no tension applied I f a scanner is used for this measurement, closing the scan cover is usually su fficient to cause the item to lie flat Likewise, placing a steel rule along the edge is usually su fficient Where a digital ruler is used, the finished product should be flattened using a flat piece o f plastic approximately mm thick, o f dimensions larger than the test piece, or a similar flattening means 9.2 Any deviation from the procedure described above shall be explicitly mentioned in the test report Calculation 0.1 General Calculate the grammage to three significant figures for each test piece using Formula (1): g= m A × 10 where g m A is the grammage of the test piece, in grams per square metre; is the mass of the test piece, in grams; is the area of the test piece, in square millimetres I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n (1) ISO 12625-6:2016(E) 10.2 Mean and standard deviation of grammage C a lc u l ate the me an gram mage o f the s ample and expre s s it to th re e s ign i fic a nt figu re s u s i ng Formula (2): n ∑ i =1 g i g= (2) n where g gi n is the mean grammage of the sample, in grams per square metre; is the grammage of the test piece, , in grams per square metre; is the number of the test pieces i C a lc u l ate the s ta nda rd deviation a nd expre s s it to two s ign i fica nt figu re s u s i ng n ∑ i =1 ( g i − g ) s= Formula (3): (3) n −1 where is the mean grammage of the sample, in grams per square metre; is the grammage of the test piece, , in grams per square metre; is the number of test pieces; is the sample standard deviation If test pieces are weighed together, calculate the grammage using Formula (4): g gi i n s n gi ∑ mi = i =1 × 10 (4) n× A where gi n m A is the grammage of the test piece, , in grams per square metre; is the number of test pieces; is the mass of the test piece in grams; i i s the are a o f e ach te s t pie ce, i n s quare m i l l i me tre s , where te s t pie ce a re as are exac tly e qua l (see 5.4) 11 Test report The test report shall include the following information: a) a reference to this document, i.e ISO 12625-6; b) the date and place of testing; c) the de s c rip tion and identi fic ation o f the s ample, s uch a s the pro duc t c ategor y a nd d i men s ion s under test; © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n ISO 62 -6: 01 6(E) d) the gra m mage, i n gra m s p er s quare me tre, rou nde d to the fi rs t de ci ma l place, numb er o f s i ngle va lue s , s ta ndard devi ation rep or te d to two s ign i fic a nt figu re s and co e ffic ient o f vari ation, rep or te d to two s ign i fic ant figu re s; e) whe ther the te s t pie ce s are weighe d to ge ther or no t (i f they are weighe d to ge ther, the s tandard deviation and co e ffic ient o f va ri ation c a nno t b e c a lc u late d) ; f) any devi ation g) the conditioning atmosphere used results; I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n from th i s c u ment and any o ther c i rc u m s tance s that may have a ffe c te d the te s t ISO 62 -6: 01 6(E) Annex A (informative) Precision A.1 General In March 2015, an international round-robin was performed with eight tissue papers and tissue products were measured with both methods described in this document (determination on cut test pieces and uncut test pieces) The results are presented in Table A.1 to Table A.4 The calculations were made according to ISO/TR 24498 [4] and TAPPI T 1200 sp-07[5] Table A.1 deviation, that is, the standard deviation is calculated as the root-mean-square of the standard f ff f f in ISO 5725-1[2] pro duc ts b y eight d i fferent lab oratorie s accord i ng to th i s c u ment T h re e o f the a s s e s s e d conver te d T he rep e atabi l ity s tand ard deviation s o devi ation rep or te d in the p ar tic ip ati ng l ab oratorie s T h i s d i is ers the “p o ole d” rep e atabi l ity s tandard rom the conventiona l defi nition o rep e atabi l ity T he rep e atabi l ity a nd repro duc ibi l ity l i m its rep or te d a re e s ti mate s o f the ma xi mu m d i fference wh ich should be expected in 19 of 20 instances, when comparing two test results for material similar to those f ff different test conditions de s c rib e d u nder s i m i la r te s t cond ition s T he s e e s ti mate s may no t b e va l id NO TE or d i erent materi a l s or T he rep e atab i l ity s ta nda rd de vi atio n a nd the with i n-l ab orator y s ta nd a rd de vi ation a re identic a l H owe ver, the rep ro duc ib i l ity s ta nda rd de viation i s no t the s a me a s b e twe en-l ab orator ie s s ta nda rd de vi atio n T he rep ro duc ib i l ity s ta nd a rd de vi ation i nclude s b o th the b e twe en-l ab orator ie s s ta nd a rd de vi ation a nd the s ta nd a rd de viation with i n a l ab orato r y, vi z : s repeatability but 2 = s within lab s reproducibility ? 2 = s within lab + s between lab ? ? NOTE 2,77=1,96 , provided that the test results have a normal distribution and that the standard deviation, s, is based on a large number of tests A.2 Measurement on cut test pieces Half of the participating laboratories used manual cutters and half used automated punches © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n ISO 12625-6:2016(E) Table A.1 — Estimation of repeatability on cut test pieces Sample Mean basis weight Repeatability standard deviation C f variation o e f i c i e n t f o Repeatability limit g/m sr g/m CV, r r % g/m to i le t- -p l y 62,9 0,49 0,78 1,4 n ky-3 -p l y 61,8 0,37 0,59 1,0 17,6 0,36 2,0 1,0 towel-2 -p l y 41,6 0,33 0,80 0,92 n ky- -p l y 58,2 0,53 0,91 1,5 toi le t-2 -p l y 7a 38,7 0,41 1,1 1,1 n ap ki n-3 -p l y 49,7 0,59 1,2 1,6 to i le t-3 -p l y 7a 48,9 0,36 0,75 1,0 virgin virgin base sheet ply vi rgin virgin virgin virgin virgin re c ycle d a Number of laboratories One outlier Table A.2 — Estimation of reproducibility on cut test pieces Sample Mean basis weight Reproducibility standard deviation C f variation o e f i c i e n t o f Reproducibility limit g/m sR g/m CV, R R % g/m to i le t- -p l y 62,9 0,66 1,1 1,8 n ky-3 -p l y 61,8 0,62 1,0 1,7 17,6 0,45 2,6 1,3 towel-2 -p l y 41,6 0,42 1,0 1,2 n ky- -p l y 58,2 0,75 1,3 2,1 toi le t-2 -p l y 7a 38,7 0,41 1,1 1,1 n ap ki n-3 -p l y 49,7 0,60 1,2 1,7 toi le t-3 -p l y 7a 48,9 0,39 0,80 1,1 virgin virgin base sheet p l y vi rg i n virgin virgin virgin virgin re c ycle d a Number of laboratories One outlier A.3 Measurement on uncut test pieces T h re e fi n i she d pro duc ts have b e en a s s e s s e d with the two pro ce du re s I n pie ce s a re made o f the u n folde d fi n i she d pro duc ts I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n Table A.3 and Table A4, test ISO 12625-6:2016(E) Table A.3 — Estimation of repeatability on uncut test pieces Sample Number of laboratories Mean basis weight Repeatability standard deviation C f variation o e f i e n t o f Repeatability limit r h a n ky-3 -p l y 60,9 0,27 % 0,45 n ky- -p l y 57,1 0,49 0,86 1,4 n ap ki n-3 -p l y 49,4 0,46 0,93 1,3 virgin virgin virgin g/m i CV, r sr g/m2 c g/m 0,8 Table A.4 — Estimation of reproducibility on uncut test pieces Sample Number of laboratories Mean basis weight Reproducibility standard deviation sR e f i c i e CV, R n t o f Reproducibility limit R h a n ky-3 -p l y 60,9 0,46 n ky- -p l y 57,1 0,83 1,5 2,3 nap ki n-3 -p l y 49,4 0,50 1,0 1,4 virgin virgin © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n g/m f variation o % 0,76 virgin g/m2 C g/m 1,3 ISO 62 -6: 01 6(E) Bibliography Paper and board — Determination o f moisture content o f a lot — Oven-drying method [1] I S O 87, [2 ] I S O 572 -1 , [3 ] I S O 575 , [4] I S O/ TR 49 , [5 ] 10 Accuracy (trueness and precision) of measurement methods and results — Part 1: General principles and definitions Paper and board — Estimation o f contraries Paper, board and pulps — Estimation of uncertainty for test methods TAPPI T 0 s p - 07, and Reproducibility I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n Interlaboratory Evaluation of Test Methods to Determine TAPPI Repeatability I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n ISO 62 -6: 01 6(E) ICS 85.060 Price based on 10 pages © ISO 2016 – All rights reserved I n tern ati o n al Org an i z ati o n fo r S tan d ard i z ati o n