Effect of Mixing Ratio on Folding Effect of Pulp Mixing Ratio on Brightness

ISBN : 978-602-17761-0-0 165 © 2013 Published by Center for Pulp and Paper through REPTech2012

3.5 Effect of Mixing Ratio on Folding

Folding endurances is the number or the number of folds that can be detained by the sample before the sample failed and folded through the prescribed angle under controlled pressure [7]. Figure 5 shows that 100 of OPF pulp gives the lowest value of 75, while 100 of ONP gives a value of 102. This can be related to the OPF virgin pulp did not under go through beatings. Secondary ONP pulp that undergoes beating process has a strong bond between the ibres and lexibility of ibres that strengthen to endurance the paper folding. In addition, the presence of additives in the paper produced from secondary ibers also improves durability of paper folding. This is through a strong resistance of relaxation of ibers by the additives illed the vacancy and pores of the paper.

3.6 Effect of Pulp Mixing Ratio on Brightness

From Fig. 6, the brightness of the paper is increasing with addition of ONP pulp. Paper brightness refers to overall light relection of the paper affected by the brightness of the pulp used. Experimental results show that the paper produced from ONP pulp is brighter than that of Acetosolv oil palm fronds pulp as can be seen in Fig.6. The presences of residual lignin remaining in Acetosolv palm fronds pulp causing light absorption occurs and make the dark-colored paper. In addition, the low brightness of paper from Acetosolv palm fronds pulp resulting from Acetosolv pulping which produced a dark-colored pulp. Figure5 shows paper produced from 100 Acetosolv oil palm fronds pulp give the lowest brightness, 14.78, and paper produced from 100 ONP pulp gives the highest brightness of 54.32. The high brightness of paper from ONP pulp might be affected by the re-bleaching of the pulp during processing. Fig. 4 Effect of Pulp Mixing Ratio on Tear Index Fig. 5. Effect of Pulp Mixing Ratio on Folding 166 © 2013 Published by Center for Pulp and Paper through REPTech2012 Conclusion Experimental results indicated that the characteristic of paper produced from mixed pulp of Acetosolv oil palm fronds pulp and pulp ONP resulted an increasing of its physical properties such as density as more as secondary pulp used. But it cannot be stated clearly if this physical properties is affected by its grammage and thickness. For mechanical properties, the increasing of pulp ONP composition used, the mechanical properties such as tensile strength, folding and fraction decreased, conversely, its tear index increased up to the level of 20, 80 ONP pulp and decreased as more secondary pulp added to the mixture. This is caused by ONP pulp has gone through the process of recapitulation. An optical property of a mixture of paper produced is increasing with increasing secondary pulp composition used. However, the mixing must be done at an optimal composition so that the paper produced meet the optimum characteristics required of paper produced. Acknowledgement The authors highly acknowledged the scholarship assistance from the Government of State of Aceh, Indonesia, which support PhD program at the Universiti Sains Malaysia USM and inancial support from Universiti Sains Malaysia through PTEKIND Short Term Research Grant No.637048 as well. Fig. 6. Effect on Pulp Mixing Ratio on Brightness References [1] Aif de Ruvo and Myat Htun. 1956Fundamental And Practical Aspects of Paper Making With Recycle Fibres, p. 195-224. [2] Fuad, M.A.; Rohana, A.R.; Chua, B.G. 1999 Socio-economic considerations in the development of jungle to oil palm. In: Singh, G. et al. Eds, Oil Palm and the Environment: A Malaysian Perspective Malaysia oil Palm Growers Council, Kuala Lumpur, 1-7p [3] Wan Rosli, W.D., Law, K.N., Valade, J.L. 1988 Chemical pulping of oil palm empty fruit bunches. Cellulose Chemistry and Technology. 32: 133- 143. [4] Law, K.N., Wan Rosli, W.D. 2001. Non-wood Materials With Special Reference to Oil Palm Fibers as Papermaking Materials: Potentials and Challenges in The New Millennium. In: Proceedings of USM- JIRCAS Joint International Symposium on Lignocellulosic Materials, Penang, Malaysia, pp. 1–137 [5] TAPPI. 1996-1997. TAPPI Test Methods 1996- 1997. Tappi Press, Atlanta USA. [6] William, E. S. and James, C. A, 1995Properties of Paper. An Introduction., Second Edition, TAPPI Press, Atlanta, Ger [7] Casey J.P. 1981Pulp and paper - Chemistry and Chemical Technology, 1981 Third Edition , volume I A Wiley - Interscience Publication , New York.3. ISBN : 978-602-17761-0-0 167 © 2013 Published by Center for Pulp and Paper through REPTech2012 Proiciency Testing to Benchmark Paper Testing Laboratory Performance Sharmiza Adnan 1 , Mahmudin Saleh Forest Products Division, Forest Research Institute Malaysia, 52109 Kepong, Selangor, Malaysia, 1 sharmizafrim.gov.my ABSTRACT Proiciency testing PT or interlaboratory-cross check ILCC has been widely used by calibration and testing laboratories as a quality assurance tool to determine the accuracy of their results. It is a Program organized periodically and participated by numerous laboratories performing a test or a range of tests speciied by the organizer. In the paper testing ield, there are currently several Programs organized worldwide. However, in the Asia Paciic region this Program is only organized by FRIM. Launched in 1998, this Program is participated by nine paper testing laboratories from all over Malaysia. Compared to other Programs, the cost incurred is very economical and the inal report is prepared based on the requirements of ISOIEC 17043: Conformity assessment General requirements for proiciency testing. This paper explains the procedures, methods used in analysing the data and information included in the inal report. Some indings and the beneits obtained by participants are also highlighted. Keywords: proiciency testing, paper testing, interlaboratory-cross check Introduction Proiciency testing PT or interlaboratory-cross check ILCC has been widely used by calibration and testing laboratories as a quality assurance tool to determine the accuracy of their results. It is a Program organized periodically and participated by numerous laboratories performing a test or a range of tests speciied by the organizer. In the paper testing ield, there are currently several Programs organized worldwide. However, the cost of participation in PT can be substantial to small companies and developing country government organizations like FRIM. The PT Program organized by FRIM was initiated in 1998 due to the absence of regional Program for paper products when the Paper Testing Laboratory in FRIM was applying for ISOIEC Guide 25 now known as ISOIEC 17025 in 1999 [1] . Being the only research institution in Malaysia having the paper testing facility, it was timely for such Program to be initiated. With the support of ive paper testing laboratories, this Program was started. Several changes have been carried out since then to fulill the requirements of new ISOIEC 17043 [2]. This paper explains the procedures, methods used in analyzing the data and information included in the inal report. The participation fee charged to laboratories for this Program is much lower than those offered in the Europe and Northern America. Some indings and the beneits obtained by participants are also highlighted. Proiciency Testing Figure 1 shows how PT is conducted at FRIM. The samples for PT can be obtained from the market or manufacturers. If obtained from manufacturers, speciic instructions are given to ensure variations in the samples are minimized. The samples are then processed in FRIM identiication of iber orientation, surface differentiation, unique ID given. Next, homogeneity testing is conducted to ensure that the variations in results submitted by participants are only due to the differences in the test methods and laboratory conditions and least likely due to sample heterogeneity. This is conducted by performing the Analysis of Variance ANOVA on the test results. If samples are not found to be homogeneous, new samples will be obtained and the process repeated until homogeneity criteria are met. Homogeneous samples are then carefully packed and distributed to participants together with an instruction sheet and result reporting forms. To enable fair reporting of results, participants are asked to provide the information on laboratory and equipment details. A speciied time frame is given to the participants to submit their results. Results can be submitted to FRIM through mail, facsimile or email. The person in charge will examine the results to detect any possible discrepancies before statistical analyses are carried out. Participants will be contacted for clariication if their results indicate inconsistencies. Due to the lack of ‘true values’ for the samples, robust statistical analyses are carried out with all participant results evaluated without any exclusion. For this purpose, medians are used instead of mean values and normalized interquartile range to estimate the standard deviations. Participant performances are evaluated using the z-score where the values below three are desired. The details on robust statistical analysis are presented in Adnan et al. [3]. The PT cycle ends when all participants accept their reports without any amendments or complaints. 168 © 2013 Published by Center for Pulp and Paper through REPTech2012 PT Final Reports The PT inal report includes all the information given to the participants, the testing conditions and results provided by them as well as interpretation of analysis results. However, the identities of participants are kept anonymous in the report. This is accomplished by assigning identiication number known only to the individual laboratories and FRIM as the organizer. The inal report also includes graphical igures comparing results from all laboratories. In particular, the Youden plots are very useful in identifying possible errors contributed by laboratory internal problems such as operators and equipment Figure 2. The purpose of generating a Youden plot is to illustrate the systematic differences between laboratories. It is drawn in a black spot representing each laboratory. The spots are generated by the results given for the same tests conducted on different samples supplied. Data points concentrated in the lower left hand and upper right hand quadrants indicate high systematic errors. Obtain new samples Sample preparation Homogeneity testing Sample distribution Sample testing Result submission Correction Statistical analysis Homogeneous? Yes Results ok? End No Report preparation No Report distribution Yes Figure 1. Flow chart of PT process 5.0 6.0 7.0 8.0 4.0 5.0 6.0 7.0 S a m p le B Sample A Moisture Content Figure 2. Sample of Youden Plot Tests Included in PT Program The range of tests included in this program is listed in Table 1. Each cycle of the Program includes at least two different types of paper products such as photocopy, test liner and corrugation medium. Thus, it caters to the needs of most paper manufacturers in Malaysia. PT Beneits and Issues Participation in PT Program offers various beneits namely 1 providing wider network, 2 encouraging closer relationship amongst industry players, 3 conforming to ISOIEC 17025 requirements, 4 providing better technical comprehension, 5 identifying internal laboratory problems, 6 improving testing quality, 7 demonstrating competence, 8 enhancing test accuracy, 9 improving customer conidence, 10 monitoring routine analysis, 11 benchmarking with peers and 12 verifying testing methods and procedures. ISBN : 978-602-17761-0-0 169 © 2013 Published by Center for Pulp and Paper through REPTech2012 Table 1. The Range of Tests Included in PT Program Organized by FRIM No. Test Preferred Standard Method Equivalent Methods ISO SCAN TAPPI ASTM BSBS EN 1 Grammage MS ISO 536 536 P6 410 D646 3432 2 Thickness MS ISO 534 534 P7 411 D645 20534 3 Moisture content oven-dry MS ISO 287 287 P4 412 D644 3433 4 Water absorptiveness MS ISO 535 535 P12 441 D3285 2644 5 Brightness MS ISO 2470 2470 P3 571 D985 4432 6 Opacity MS ISO 2471 2471 P8 519 D589 7 Burst strength MS ISO 2758 2758 P24 403 D774 3137 8 Tear strength MS ISO 1974 1974 P11 414 D689 21974 9 Tensile strength MS ISO 1924-2 1924-2 P38 494 D828 4415 10 Bending resistance MS ISO 2493 2493 P29 489 D5342 3748 11 Ring crush TAPPI 822 or 818 12192 P34 - D1164 NA Despite the above beneits, some of the issue faced by PT organizers like FRIM are 1 instructions not fully followed by participants which results in tests being conducted for wrong sampleiber direction surface, 2 results are reported ‘raw’, e.g., weight reported instead of grammage, 3 insuficient information given, e.g., units not reported, 4 variation in test methods different specimen size, time, etc., 5 equipment used by participants have different principles, e.g., light source for brightness and opacity and 6 different equipment resolution, e.g., 1 micron vs. 0.1 micron for caliper. Conclusion Proiciency testing PT is an effective quality assurance tool used by laboratories to verify the accuracies of their results. In this Program, samples are distributed amongst participating laboratories who will conduct tests speciied by the organizer. Results are then submitted to be analyzed by the organizer. Most organizers specify the test methods to be used as a means to minimize variations in results submitted by participants. Participation in PT offers several beneits including the ability to benchmark the quality of test results, identify laboratory problems and to improve customer conidence. Besides these beneits, PT participation could also provide wider network and encourage closer relationship between laboratories with similar facilities. Although PT offers numerous advantages, several challenges have been identiied and overcome with some precaution and proactive steps by the organizer to ensure smooth execution of the Program. Due to the limited availability of PT Programs for paper products in the Asia Paciic region, the cost of participation is quite high. This cost can be reduced by having more Programs organized in different regions as initiated by FRIM. References [1] ISO, ISOIEC Guide 25, General Requirements for the Competence of Testing and Calibration Laboratories 1999. [2] ISO, ISOIEC 17043, Conformity Assessment – General Requirements for Proiciency Testing 2010. [3] Sharmiza A., Latifah J., Mahmudin S. and Mohd Nor M.Y., Establishment of a Proiciency Testing PT Scheme for Paper Products: A Malaysian Experience, Appita Journal, 64 2011 30. 170 © 2013 Published by Center for Pulp and Paper through REPTech2012