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PRELIMINARY TESTS REGARDING THE ENDOGENOUS AND EXOGENOUS ENDOGENOUS AND EXOGENOUS
FACTORS THAT INDUCE BOOK AND DOCUMENTDOCUMENT
DEGRADATION
Catalina Mihaela Talasman, Constantin Stanciu, Daniela ManeaResearch Department SC CEPROHART SA Braila ROMANIAResearch Department SC CEPROHART SA, Braila, ROMANIA
Valentin I MoiseTechnological Irradiation Centre, Physics and Nuclear Engineering
Institute “Horia Hulubei”, Bucharest, ROMANIA
The main characteristics that defines the paper p pdurability
Were performed determinations for the main characteristics that defines the papers’ p p pdurability: breaking load, breaking length, folding endurance, whiteness, bursting strength, Cobb size test, opacity, tearing resistance according to the following standards:
• Grammage SE EN ISO 536:97, • Thickness SR EN ISO 534:2005, ,• Breaking length SR EN ISO 1924- 2:2009, • Opacity ISO 2471:2008, • Sizing STAS 4748:1985, • Whiteness ISO 2470-1:2009, • Smoothness SR ISO 5627:1995• Smoothness SR ISO 5627:1995, • Bursting strength SR EN ISO 2758:2004, • Tearing resistance SR EN 21974:97 g• Cobb size test SR EN 20535:96 • Folding endurance SR ISO 5626:96
SR ISO 5630 1 :1995 Paper and board• SR ISO 5630-1 :1995. Paper and board. Accelerated ageing. Part 1: Dry heat treatment at 100oC
• SR ISO 5630-3 :1997. Paper and board.SR ISO 5630 3 :1997. Paper and board. Accelerated ageing. Part 3: Moist heat treatment at 80oC and 65% relative humidity80oC and 65% relative humidity
• SR ISO 5630-4 :1996 Paper and board. Accelerated ageing. Part 4: Dry heat treatment at 120oC or 150oC
• SR ISO 9706: 1996 – Information and documentation Paper for documentsdocumentation. Paper for documents. Requirements for performance
THE CAUSES THAT PRODUCES PAPER AGEINGCOULD BE DIVIDED IN TWO MAIN CATEGORIES:
• The category of internal or endogenous factors that consists of the raw materials nature and that consists of the raw materials nature and the manufacturing category of process
tparameters
• The category of external or endogenous factors that comprises the influence of environment that comprises the influence of environment (temperature, humidity, corrosive gases,
i i t )microorganisms etc)
The experimental program consists in an accelerated ageing process performed on:g g p p
a) samples of old documents naturally aged and manufactured in 1881 2006manufactured in 1881 ÷ 2006
b) tests realized on paper samples obtained at laboratory scale and in various conditions
Both sets of experimentations evaluated the Both sets of experimentations evaluated the influence of the endogenous and exogenousfact the h ical a d echa ical factors on the physical and mechanical properties of paper sheets providing information regarding their resistance to the ageing processg g p
a. Laboratory scale experimentations performed l i d f ld d on samples various grades of old paper and
documentsWithin the experimental program we used samples of:Batch no. 1
W t k SC L t SA B ă (WMP)Watermark paper SC Letea SA Bacău (WMP)Coated paper SC GHIMBAV SA (CP)Neutral sized copy paper manufactured in Austria (XP)Neutral sized copy paper manufactured in Austria (XP)
Batch no. 2Pronosport paper 70 g/m2 (the first neutral sized paper manufactured in Romania)manufactured in Romania)1A type paper 60 g/m2 (the first neutral sized paper manufactured in Romania)
Batch no. 3pages from a book printed in 1940 in Romania (private library)pages from a book printed in 1981 in Romania (private library)pages from a book printed in 1981 in Romania (private library)
Batch no. 4pages from a book printed in 1923 in France (private library)
b. Laboratory scale experimentations performed l d f t d th on paper sampled manufactured on the
CEPROHART PM or in the RD laboratory and submitted to an accelerated ageing process in
various conditionsAnother set of experiments were performed on:
A class copy paper with a grammage of 80 g/m2A class copy paper with a grammage of 80 g/mmanufactured on the SC CEPROHART SA Brăila paper machinepaper machineTwo handsheet sets on the Rapid Köthen sheet former from CEPROHART’s pulp laboratory
Paper grade Paper grade
CharacteristicsWatermark
paper LETEA BACĂU
Coated paper ECOPACKGHIMBAV
Watermarkpaper
LETEA BACĂU
Coated paper ECOPACKGHIMBAVLETEA BACĂU
Manufactured in 1996
GHIMBAVManufactured in
1996
LETEA BACĂUManufactured in
1996
GHIMBAVManufactured in
1996
Grammage, g/m2 91 97,0 91 96,8
Breaking load,N, L/T
123/38 86/34 112/34,6 75/29
Breaking length m 9200/2840 6033/2375 8364/2584 5246/2065Breaking length, m, L/T
9200/2840 6033/2375 8364/2584 5246/2065
Whiteness, % 55 86 50 76(yellow paper) (yellow paper)
T i i t 765/1048 334/417 693/953 290/363Tearing resistance, mN, L/T
765/1048 334/417 693/953 290/363
Folding endurance, 55/260 9/16 52/232 8/14g ,nr, L/T
9000
10000Breaking length WMPBreaking length CP 80
90 Whiteness WMP Folding Endurance WMP
Whiteness CP Folding Endurance CP
5000
6000
7000
8000
Breaking length CP
50
60
70
80
2000
3000
4000
5000
20
30
40
0
1000
1996 2009 0
10
1996 2009
Evolution of breaking length, tearing and bursting strength, whiteness, Cobb size test, folding endurance for watermark paper and coated paper from 1996
600
700
800 Breaking Load WMPTearing resistance WMPBreaking Load CP
300
400
500Tearing resistance CP
100
200
300
01996 2009
Paper grade
Characteristics Neutral sized Copy paper
Neutral sized Copy paper
AUSTRIAManufactured in 2006
AUSTRIAManufactured in 2009
Grammage g/m2 78 0 77 5Grammage, g/m 78,0 77,5
Breaking load, N, L/T 83/41 75,9/37,3g , , , ,
Breaking length, m, L/T 7970/3920 6640/3263
Whiteness, % 100 98
Tearing resistance, mN, L/T 415/445 347/373
Folding endurance, no., L/T 18/36 17/33
9000
10000Breaking length HX
450 Breaking load HX
5000
6000
7000
8000
250300
350
400 Tearing strength HX
1000
2000
3000
4000
50
100
150
200
02006 2009
02006 2009
Evolution of tearing strength, breaking length, whiteness and folding endurancefor a neutral sized copy paper manufactured in Austria in 2006
60708090
100Whiteness HX
Folding endurance HX
2030405060
010
2006 2009
Initial1996
Natural ageing 13 years
Accelerating ageing
Characteristics
1996 13 years
1A Pronosportpaper
1A Pronosportpaper
1A Pronosportpaper
Grammage, g/m2 63,5 70,0 62,7 69,7 62,4 69,5
Breaking length, m 4100 4570 3633 3805 3486 3650
Sizing, mm > 2 0,5 > 2 0,5 > 2 0,5
Whiteness, %R457/D65
87,0 80,0 85,0 69,7 83,37 69,0
T i 160 160 120 120 60 60Tearing resistance,mN
160 160 120 120 60 60
400045005000
Breaking length 1A
Breaking length PRONO350
400
450 Breaking load HXTearing strength HX
2000250030003500
150
200
250
300
350
0500
10001500
1996 2009 IN 2009 IA
0
50
100150
2006 20091996 2009 IN 2009 IA
Evolution of tearing strength, breaking length, whiteness for two neutral sized copy paper grades 1A Evolution of tearing strength, breaking length, whiteness for two neutral sized copy paper grades 1A and PRONOSPORT manufactured in 1996
100 Whiteness 1AWhiteness PRONO
50
001996 2009 I N 2009 I A
Characteristics
Sample of paper pages took from different book areasBook printed in 1923 in France
Characteristics1 2 3 4 5 6 7 8 9 10
Breaking 41 3/ 37 3/ 38 4/ 35 4/ 23 9/ 25 1/ 25 4/ 28 7/ 26 4/ 28 3/Breakingload, N, L/T
41,3/22,1
37,3/21,6
38,4/21,2
35,4/15,1
23,9/15,7
25,1/15,8
25,4/11,3
28,7/10,9
26,4/15,5
28,3/13,3
Breakinglength, m,L/T
3845/2053
3472/2011
3575/1974
3296/1406
2225/1462
2337/1471
2365/1052
2672/1015
2458/1443
2635/1238length, m,L/T 2053 2011 1974 1406 1462 1471 1052 1015 1443 1238
Foldingendurance,no, L/T
2/4 2,4 2/4 3/3 1/1 2/2 2/2 2/2 4/4 4/5
%Whiteness, % 55,26 56,32 57,59 59,48 59,73 58,57 58,37 58,98 58,84 59,07
4000
3500
Breaking length
2500
3000
20001 2 3 4 5 6 7 8 9 10
The evolution of breaking length and whiteness inside the book from 1923
60
Whiteness
60
451 2 3 4 5 6 7 8 9 10
Characteristics Book 1981 Book 1981Characteristics Book 1981Initial
Book 1981NA
Grammage, g/m2 50,0 49,4
Breaking load, N, L/T 20,0/12,0 18,5/10,4
Breaking length, m, L/T 2700/1500 2548/1432
Whiteness, % R457/C 55,0 40,69Whiteness, % R457/C 55,0 40,69
B kk th F/S 35/28 34/26Bekk smoothness, s, F/S 35/28 34/26
2900
3000Breaking length
2700
2800
2900
2400
2500
2600
2300
2400
1981 2009 NA
The evolution of breaking length and whiteness after a natural ageing process of 19 years (book from 1981)
100Whiteness
50
01981 2009 NA
Paper sample
Characteristics
class copy paper with a grammage of 80 g/m2 manufactured on the SC CEPROHART SA Brăila paper machine
Initial Accelerating ageing72 hours72 hours
Grammage, g/m2 78 77,7
B ki l h 6216 6010Breaking length, m 6216 6010
Sizing, mm >2 >2
Whiteness, % R457/D65 86,48 83,14
Bursting strength, kPa 164 141
Tearing resistance mN 342 312Tearing resistance, mN 342 312
Cobb size test , g/m2 17,5/19,1 16,2/18,7
Folding endurance, nr, L/T 26/30 8/17
Breaking load400
Bursting strengthBreaking load
300
Tearing resistance
100
200
5500initial AA
100initial AA
Evolution of tearing resistance and bursting strength, of whiteness, Cobb size test, folding enduranceEvolution of tearing resistance and bursting strength, of whiteness, Cobb size test, folding endurancefor A class copy paper 80g/m2
80
100 WhitenessCobbFolding Endurance
40
60
0
20
40
0initial AA
Recipe Hardwood pulp, % Softwood pulp, % CaCO3 , % AQUAPEL, % CARTARETINE, %
P1 30 70 - 0,2 -
P2 30 70 25 1,5 0,8
Characteristics Sample 1 Sample 2
Breaking load, N 52,5 39,4
Breaking length, m 6725 5980
Tensile strength, kN/m 3,50 2,63
Folding endurance, no 251 99
Tearing resistance, mN 140 100
Bursting strength, kPa 222 109
Cobb60 size test-, g/m2 66,3 49,9
Characteristics P124T P148T P172T P196T P224T P248T P272T P296T
Breaking load, N 58,2 59,3 59,8 62,0 38,2 30,1 29,2 29,0
Breaking length, m 7461 7438 7600 8045 5806 4550 4410 4400
Tensile strengthkN/m
3,88 3,95 4,18 3,87 2,55 2,00 1,95 2,07
Foldingendurance, no
182 177 139 133 90 33 30 29
Tearingstrength, mN
110 100 96 76 90 68 64 52
Burstingstrength kPa
214 209 198 186 108 99 96 90
Cobb60- size test, g/m2
57,2 56,0 55,5 54,7 42,8 47,9 50,9 51,3
Bursting strengthT i i t
200Tearing resistance
100
0P1 P1-24 P1-48 P1-72 P1-96 P2 P2-24 P2-48 P2-72 P2-96
Evolution of bursting strength, tearing resistance, breaking load, folding endurance and Cobb size test at 105°C and 24, 48, 72 and 96 hours
200
250Breaking loadFolding EnduranceCobb
150
50
100
0P1 P1-24 P1-48 P1-72 P1-96 P2 P2-24 P2-48 P2-72 P2-96
Characteristics P124U P148U P172U P196U P224U P248U P272U P296U
Breaking load, N 57,3 58,1 58,6 48,9 27,6 27,6 28,9 30,2
Breaking length, m 7389 7460 7512 6271 4168 4165 4380 4556
Tensile strength,kN/m
3,84 3,88 3,91 3,26 1,84 1,84 1,93 2,01
Foldingendurance, no
192 190 215 215 39,0 45,0 27,0 30,0
Tearingstrength, mN
80 84 100 90 80,0 80,0 84,0 90,0
Burstingstrength, kPa
194 192 211 209 88,0 98,0 90,0 95,0
Cobb60 size test-, g/m2
62,3 62,0 62,3 63,0 57,7 57,1 59,3 57,1
Bursting strength
200
Bursting strengthTearing resistance
100
0P1 P1-24 P1-48 P1-72 P1-96 P2 P2-24 P2-48 P2-72 P2-96
Evolution of bursting strength, tearing resistance, breaking load, folding endurance and Cobb size test at RH (relative humidity) of 65% and 24, 48, 72 and 96 hours
200
250
Breaking load
100
150
Breaking loadFolding enduranceCobb
50
100
0P1 P1-24 P1-48 P1-72 P1-96 P2 P2-24 P2-48 P2-72 P2-96
Characteristics P1 P124S P148S P172S P196S P2 P224S P248S P272S P296S
Breaking load, N 52,5 35,8 36,4 35,0 33,9 39,4 25,3 25,1 30,14 28,0
Breaking length, m 6725 4594 4670 4487 4356 5980 3814 3793 4675 4194
Tensile strength,kN/m
3,5 2,39 2,43 2,33 2,26 2,63 1,68 1,67 2,06 1,86
F ldi 251 153 154 108 104 99 103 105 108 91Foldingendurance,no
251 153 154 108 104 99 103 105 108 91
Tearing strength,mN
140 40 40 20 20 100 70 60 70 60
Bursting strength 222 184 45 21 19 109 43 24 19 16Bursting strength,kPa
222 184 45 21 19 109 43 24 19 16
Cobb60 size test, g/m2 66,3 63,3 62,8 60,9 59,6 49,9 40,7 58,8 60 60,7
Yellow index, % 46,05 31,8 28,32 27,22 23,97 50,26 49,13 48,74 46,3 44,77
200 Bursting strength200 Bursting strengthTearing resistance
100
0P1 P1-24 P1-48 P1-72 P1-96 P2 P2-24 P2-48 P2-72 P2-96
Evolution of bursting strength, tearing strength, breaking load, folding endurance and Cobb size test in SO2 atmosphere and 24, 48, 72 and 96 hours
225
250
275Breaking loadFolding enduranceCobb
125
150
175
200
25
50
75
100125
0
25
P1 P1-24 P1-48 P1-72 P1-96 P2 P2-24 P2-48 P2-72 P2-96
R l ti i t t tifi i l Relative resistance to artificial ageingageing
A 10000 X
BAR =
R th l ti i t t tifi i l R = the relative resistance to artificial ageingageing
A = the value obtained after the artificial ageing process
B = the initial value of the blankB = the initial value of the blank
Paper manufactured in the RD laboratory p y
Folding enduranceRecipe 1• Accelerating ageing at 105°C R = 52 98%• Accelerating ageing at 105°C R = 52,98%• Accelerating ageing at 65% RH R = 85,65%• Accelerating ageing in SO2 atmosphere R= 41,43%Recipe 2• Accelerating ageing at 105°C R= 29,3%• Accelerating ageing at 65% RH R = 30,3%Accelerating ageing at 65% RH R 30,3%• Accelerating ageing in SO2 atmosphere R = 91,92%
Paper manufactured in the RD laboratory Breaking load
Recipe 1 • Accelerating ageing at 105°C R = 118%• Accelerating ageing at 105 C R = 118%• Accelerating ageing at 65% RH R = 93,1%
A l i i i SO h R 64 %• Accelerating ageing in SO2 atmosphere R= 64,5%Recipe 2• Accelerating ageing at 105°C R= 73,6%• Accelerating ageing at 65% RH R= 76,6%Accelerating ageing at 65% RH R 76,6%• Accelerating ageing in SO2 atmosphere R = 71,0%
Paper manufactured in the RD laboratory Tearing strength
Recipe 1• Accelerating ageing at 105°C R = 54 3%• Accelerating ageing at 105 C R = 54,3%• Accelerating ageing at 65% RH R = 86,5%• Accelerating ageing in SO atmosphere R= 19 2%• Accelerating ageing in SO2 atmosphere R= 19,2%
Recipe 2Recipe 2• Accelerating ageing at 105°C R= 52,0%
A l ti i t 65% RH R 90 0%• Accelerating ageing at 65% RH R= 90,0%• Accelerating ageing in SO2 atmosphere R= 60,0%
Paper manufactured on the CEPROHART Paper manufactured on the C PROHART PM
The values of R are after 72 hours at 105°C• Whiteness R = 96,13%• Bursting strength R = 86%• Bursting strength R = 86%• Tearing strength R = 91,2%g g , %• Folding endurance R = 30,8 %• Cobb60 R = 92,6%
CONCLUSIONSCONCLUSIONS
• The importance of paper ageing process is strongly connected to the final utilization of the product and the connected to the final utilization of the product and the period of time after which the ageing process effects became visiblebecame visible
• The ageing process of the cellulosic fibrous materials determines transformations of the polysaccharide determines transformations of the polysaccharide compounds that manifests by modifications of the physico-chemical properties, by resistance property deterioration and whiteness decreasingp p y g
Th i l ti f ti l h t i ti i l • The involution of optical characteristics is slower than of the physico-mechanical properties of paper p y p p p pbased documentsTh f t t t k i t t th • The paper manufacturer must take into account the final utilization of paper in the moment when he p pestablishes the paper recipe
• A judicious selection of pulp furnish, alkaline sizing, utilization of calcium carbonate as filler assures the utilization of calcium carbonate as filler assures the premises to obtain some paper grades with a very
d d bilit good durability.
In order to increase paper stability we could choose one of the followingIn order to increase paper stability we could choose one of the followingmethods:
• Optimal pulp furnishes taking into account the Optimal pulp furnishes, taking into account the properties of different pulps (cotton, rags, sulfate, sulfite, wastepaper, mechanical pulp)
• Utilization of some polymers (polyether) in order to p y (p y )protect mechanical pulp or paper pulps within the color reversion process induced by lightreversion process induced by light
• To avoid the utilization of brighteners within time durable papers compositiondurable papers composition
• Surface treatment at the sizing press with starch and casein solutionscasein solutions
• Introduction of some buffer solutions within paper composition in order to mitigate the influence of air oxygen on the oxidative degradation (CaCO3, K2CO3, oxygen on the oxidative degradation (CaCO3, K2CO3, MgCO3, CaCO3· MgCO3)
• Paper treatment with antiseptic non-volatile compounds in order to increase the resistance to microorganism in order to increase the resistance to microorganism action
• Utilization of ionizing radiationsUtilization of ionizing radiations
• Utilization of modified pulps (grafted groups) or synthetic fibers at paper manufacturingsynthetic fibers at paper manufacturing
• Utilization of paper deacidifying methods
In order to extend the life cycle of the document papers is necessarynecessary
To assure appropriate storage conditions as regards t t h idit i i th i f temperature, humidity, corrosive gases in the air, for the entire document categories (new or old). SO2 gases g ( ) 2 ghave the most destructive effect
Utilization of new paper grades suitable to be used for archiving that will correspond to the requirements archiving that will correspond to the requirements imposed by the permanence conditions and an accurate selection of additives used within the paper grade composition in order to obtain positive effects grade composition in order to obtain positive effects during the entire document life cycleUtilization of modern methods to disinfest the archives with minimum effect on paper resistance archives with minimum effect on paper resistance characteristics (utilization of gamma radiations)
A i i t t t b t ti ll d Ageing resistance must to be systematically and differently studied throughout the following periods of y g g ptime: 1806, 1806-1990, after 1990 all correlated with the appearance of neutral alkaline sizing and with the the appearance of neutral-alkaline sizing and with the introduction of a number of additivesThe knowledge of the ageing process mechanism, of endogenous and exogenous factors allows endogenous and exogenous factors, allows establishing possibilities to increase paper durabilityg p p p y
The present researches are guided to the simulation of natural The present researches are guided to the simulation of natural ageing phenomena, by accelerated ageing on short periods of time in order to study paper behavior in comparison with the time, in order to study paper behavior in comparison with the main physical and chemical agent’s destruction agentsAssessment of paper resistance to the ageing process Assessment of paper resistance to the ageing process, assumes that modifications due to ageing, are to be characterized through determination of some properties characterized through determination of some properties, generally strength properties (furnish, grammage, tearing strength folding endurance aqueous extract pH alkali reserve strength, folding endurance, aqueous extract pH, alkali reserve etc) A paper resistant to ageing after a period of time still present’s minimum values of those properties that allow the paper to be used in accordance with its initial purpose