CN1720369A - Method for improving the discoloration resistance of pulp and pulp improved in discoloration resistance - Google Patents
Method for improving the discoloration resistance of pulp and pulp improved in discoloration resistance Download PDFInfo
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- CN1720369A CN1720369A CNA2003801048629A CN200380104862A CN1720369A CN 1720369 A CN1720369 A CN 1720369A CN A2003801048629 A CNA2003801048629 A CN A2003801048629A CN 200380104862 A CN200380104862 A CN 200380104862A CN 1720369 A CN1720369 A CN 1720369A
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- pulp
- paper pulp
- bleaching
- fadedness
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- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000002845 discoloration Methods 0.000 title abstract 6
- 229920001131 Pulp (paper) Polymers 0.000 claims abstract description 68
- 150000002978 peroxides Chemical class 0.000 claims abstract description 19
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 18
- 150000002894 organic compounds Chemical class 0.000 claims abstract description 16
- 239000000203 mixture Substances 0.000 claims abstract description 5
- 238000004061 bleaching Methods 0.000 claims description 34
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 17
- 150000001875 compounds Chemical class 0.000 claims description 17
- 239000001257 hydrogen Substances 0.000 claims description 17
- 229910052739 hydrogen Inorganic materials 0.000 claims description 17
- 230000006872 improvement Effects 0.000 claims description 9
- 239000000126 substance Substances 0.000 claims description 7
- 238000005562 fading Methods 0.000 abstract description 27
- 230000008569 process Effects 0.000 abstract description 13
- 230000000694 effects Effects 0.000 abstract description 10
- 239000000654 additive Substances 0.000 abstract description 4
- 230000007613 environmental effect Effects 0.000 abstract description 4
- 230000001678 irradiating effect Effects 0.000 abstract 1
- 229920005610 lignin Polymers 0.000 description 24
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 description 18
- 239000013256 coordination polymer Substances 0.000 description 11
- 239000000463 material Substances 0.000 description 11
- 239000004155 Chlorine dioxide Substances 0.000 description 10
- 238000005516 engineering process Methods 0.000 description 10
- -1 hydroquinone compound Chemical class 0.000 description 10
- 239000002904 solvent Substances 0.000 description 10
- 239000002253 acid Substances 0.000 description 9
- 235000019398 chlorine dioxide Nutrition 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 239000007787 solid Substances 0.000 description 7
- AZQWKYJCGOJGHM-UHFFFAOYSA-N 1,4-benzoquinone Chemical compound O=C1C=CC(=O)C=C1 AZQWKYJCGOJGHM-UHFFFAOYSA-N 0.000 description 6
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 6
- 239000003513 alkali Substances 0.000 description 6
- 230000008901 benefit Effects 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 6
- 125000000217 alkyl group Chemical group 0.000 description 5
- 125000003118 aryl group Chemical group 0.000 description 5
- 238000004040 coloring Methods 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 5
- 229910021645 metal ion Inorganic materials 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- 239000012279 sodium borohydride Substances 0.000 description 5
- 229910000033 sodium borohydride Inorganic materials 0.000 description 5
- 229910052724 xenon Inorganic materials 0.000 description 5
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 230000004075 alteration Effects 0.000 description 4
- 238000005984 hydrogenation reaction Methods 0.000 description 4
- 238000013532 laser treatment Methods 0.000 description 4
- 150000001451 organic peroxides Chemical class 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N 1,4-Benzenediol Natural products OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 3
- 239000004215 Carbon black (E152) Substances 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- 230000000996 additive effect Effects 0.000 description 3
- 150000001639 boron compounds Chemical class 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 125000004432 carbon atom Chemical group C* 0.000 description 3
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 239000000835 fiber Substances 0.000 description 3
- XPFVYQJUAUNWIW-UHFFFAOYSA-N furfuryl alcohol Chemical compound OCC1=CC=CO1 XPFVYQJUAUNWIW-UHFFFAOYSA-N 0.000 description 3
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 239000012978 lignocellulosic material Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 238000011282 treatment Methods 0.000 description 3
- 241000931526 Acer campestre Species 0.000 description 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- 206010033546 Pallor Diseases 0.000 description 2
- KFSLWBXXFJQRDL-UHFFFAOYSA-N Peracetic acid Chemical compound CC(=O)OO KFSLWBXXFJQRDL-UHFFFAOYSA-N 0.000 description 2
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 2
- 235000011613 Pinus brutia Nutrition 0.000 description 2
- 241000018646 Pinus brutia Species 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 125000004453 alkoxycarbonyl group Chemical group 0.000 description 2
- 125000004448 alkyl carbonyl group Chemical group 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000007900 aqueous suspension Substances 0.000 description 2
- 125000005129 aryl carbonyl group Chemical group 0.000 description 2
- 125000005161 aryl oxy carbonyl group Chemical group 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 2
- 239000001913 cellulose Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000007598 dipping method Methods 0.000 description 2
- GRWZHXKQBITJKP-UHFFFAOYSA-L dithionite(2-) Chemical compound [O-]S(=O)S([O-])=O GRWZHXKQBITJKP-UHFFFAOYSA-L 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000009897 hydrogen peroxide bleaching Methods 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 229910052753 mercury Inorganic materials 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 238000010525 oxidative degradation reaction Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 150000004965 peroxy acids Chemical class 0.000 description 2
- 238000004076 pulp bleaching Methods 0.000 description 2
- 150000004053 quinones Chemical class 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 125000001424 substituent group Chemical group 0.000 description 2
- 239000006097 ultraviolet radiation absorber Substances 0.000 description 2
- JNIQBPHJIAOMQU-FSIIMWSLSA-N (2s,3s,4s,5r)-2,3,4,5-tetrahydroxy-6-oxoheptanoic acid Chemical compound CC(=O)[C@H](O)[C@@H](O)[C@H](O)[C@H](O)C(O)=O JNIQBPHJIAOMQU-FSIIMWSLSA-N 0.000 description 1
- WOAHJDHKFWSLKE-UHFFFAOYSA-N 1,2-benzoquinone Chemical compound O=C1C=CC=CC1=O WOAHJDHKFWSLKE-UHFFFAOYSA-N 0.000 description 1
- LJGHYPLBDBRCRZ-UHFFFAOYSA-N 3-(3-aminophenyl)sulfonylaniline Chemical compound NC1=CC=CC(S(=O)(=O)C=2C=C(N)C=CC=2)=C1 LJGHYPLBDBRCRZ-UHFFFAOYSA-N 0.000 description 1
- 102100031260 Acyl-coenzyme A thioesterase THEM4 Human genes 0.000 description 1
- 241000196324 Embryophyta Species 0.000 description 1
- 229920002488 Hemicellulose Polymers 0.000 description 1
- 101000638510 Homo sapiens Acyl-coenzyme A thioesterase THEM4 Proteins 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 125000002777 acetyl group Chemical group [H]C([H])([H])C(*)=O 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 239000011149 active material Substances 0.000 description 1
- 150000001335 aliphatic alkanes Chemical class 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 125000005428 anthryl group Chemical group [H]C1=C([H])C([H])=C2C([H])=C3C(*)=C([H])C([H])=C([H])C3=C([H])C2=C1[H] 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 125000003236 benzoyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C(*)=O 0.000 description 1
- 239000007844 bleaching agent Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- MMCOUVMKNAHQOY-UHFFFAOYSA-N carbonoperoxoic acid Chemical compound OOC(O)=O MMCOUVMKNAHQOY-UHFFFAOYSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 229910001902 chlorine oxide Inorganic materials 0.000 description 1
- 150000001924 cycloalkanes Chemical class 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000017858 demethylation Effects 0.000 description 1
- 238000010520 demethylation reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- HRKQOINLCJTGBK-UHFFFAOYSA-L dioxidosulfate(2-) Chemical compound [O-]S[O-] HRKQOINLCJTGBK-UHFFFAOYSA-L 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 125000003754 ethoxycarbonyl group Chemical group C(=O)(OCC)* 0.000 description 1
- 125000004672 ethylcarbonyl group Chemical group [H]C([H])([H])C([H])([H])C(*)=O 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 230000005283 ground state Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 231100000086 high toxicity Toxicity 0.000 description 1
- 238000006197 hydroboration reaction Methods 0.000 description 1
- YVJRCWCFDJYONJ-UHFFFAOYSA-N hydroperoxymethylbenzene Chemical compound OOCC1=CC=CC=C1 YVJRCWCFDJYONJ-UHFFFAOYSA-N 0.000 description 1
- 229910001410 inorganic ion Inorganic materials 0.000 description 1
- 229910052743 krypton Inorganic materials 0.000 description 1
- 239000004611 light stabiliser Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 125000001160 methoxycarbonyl group Chemical group [H]C([H])([H])OC(*)=O 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 125000001624 naphthyl group Chemical group 0.000 description 1
- 125000005185 naphthylcarbonyl group Chemical group C1(=CC=CC2=CC=CC=C12)C(=O)* 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 125000001453 quaternary ammonium group Chemical group 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 239000010948 rhodium Substances 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- PFUVRDFDKPNGAV-UHFFFAOYSA-N sodium peroxide Chemical compound [Na+].[Na+].[O-][O-] PFUVRDFDKPNGAV-UHFFFAOYSA-N 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- DZLFLBLQUQXARW-UHFFFAOYSA-N tetrabutylammonium Chemical compound CCCC[N+](CCCC)(CCCC)CCCC DZLFLBLQUQXARW-UHFFFAOYSA-N 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
Images
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/001—Modification of pulp properties
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H11/00—Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only
- D21H11/16—Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only modified by a particular after-treatment
- D21H11/20—Chemically or biochemically modified fibres
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1026—Other features in bleaching processes
- D21C9/1047—Conserving the bleached pulp
Abstract
The present invention aims to provide a method for improving discoloration in pulp, characterized by a versatile technique adaptable to any type of pulp, a time-saving process, a great and permanent anti-fading effect, environmental friendliness and other properties, as well as a pulp with greatly improved discoloration obtained by said method for improving discoloration. Discoloration in pulp can be greatly improved by adding one or more additives selected from the group consisting of reducing agents, peroxides and hydrogen-donating organic compounds to one of bleached mechanical pulp, semi-chemical pulps, chemical pulp and deinked pulps or a mixture of two or more of them, and irradiating it with UV and/or visible light.
Description
Technical field
The present invention relates to improve the method for paper pulp fadedness, more particularly, relate to the use specific compound, improve the new method of paper pulp fadedness and relate to the paper pulp that is improved by this fadedness of improving the method preparation of fadedness.
Prior art
For the paper pulp of any kind, comprising chemical pulp (hereinafter referred to as CP) as KP, AP, SP; Semichemical wood pulp (hereinafter referred to as SCP); Mechanical pulp (hereinafter referred to as MP) is as SGP, RGP, PGW, TMP, CTMP, BCTMP; And de inked pulp (hereinafter referred to as DIP), as time goes by, the loss of whiteness of paper pulp or to fade be common problem.The paper pulp fading extent mainly is subjected to the lignin of residual quantity in the paper pulp or the influence of modified lignin, and when the residual quantity of lignin or modified lignin increases, tends to occur fading.Therefore, occurring the soonest fading in the MP that is characterised in that low bleaching degree, follow by SCP, is CP then.Fadedness greatly is subjected to the influence of MP content or other factors in DIP.
In the bleaching process of paper pulp, lignin is oxidized, produces quinhydrones as modified lignin.This quinhydrones by the reaction oxidation shown in the diagram 1, obtains quinone easily, thereby causes fading.Residual not oxidation lignin is excited under ultraviolet light equally in the paper pulp, and by the reaction oxidative degradation shown in the diagram 2, produces naphtoquinone compounds freshly, thereby causes fading.Therefore, the conventional method of improving the paper pulp fadedness is usually included in the paper pulp bleaching process process, by adding bleaching chemical or alkaline chemical, causes decolourant such as lignin or modified lignin thereby degrade or remove.
According to the conventional method of improving the CP fadedness, make to cause decolourant degraded and remove with chemicals or analog.Yet, in the method, must use a large amount of chemicals or analog, degrading/to remove lignin, and these processing cause the problem such as causing bleached pulp loss or paper pulp fiber loss of strength.Require a large amount of acid to remove hexenuronic acid, hexenuronic acid also causes the problem of paper pulp fiber loss of strength.If can make naphtoquinone compounds degraded in advance, then expection has such as the steady quality of the paper product of being made by CP and the advantage can developing new product.
As the example of prior art, document shows that under alkali condition during the hydrogen peroxide bleaching stage, under higher temperature, longer reaction time section ground adopts higher concentration of hydrogen peroxide, improves preferably by fade (referring to non-patent literature 1).Being awarded Patent right a kind of bleaching process is characterised in that, when bleaching the paper pulp of deriving in proper order by ligno-cellulosic materials by the bleaching of forming by chlorine and/or chlorine dioxide stage-alkali/oxygen stage-chlorine dioxide stage-chlorine dioxide stage, in first reaction of continuous chlorine dioxide stage, add alkali in the later stage, and the ratio of chlorine dioxide is 40/60-70/30 (referring to a patent documentation 1) in the first pair of second stage.The multistage bleaching process also has been awarded patent right, comprising following step: the paper pulp of deriving by ligno-cellulosic materials with chlorine treatment, alkaline extraction, hypochlorite is handled then, it is characterized in that, during the hypochlorite bleaching stage, based on the weight that parches of paper pulp, add 1.0% or many alkali, and under 60 ℃ or higher temperature pulp treatment (referring to patent documentation 2).A kind of technology is disclosed, it is characterized in that, comprise the paper pulp of bleaching in the order of at least one chlorine bleaching stage therein with the zytase processing, and further bleaching (referring to patent documentation 3) in comprising the bleaching order of hypochlorite stage and chlorine dioxide stage.The preparation method of the paper pulp with high whiteness is disclosed, the ratio that it is included in chlorine dioxide/alkali is under the 1/0.05-1/0.3, at high temperature, order by sulfoxylate bleaching stage and chlorine dioxide bleaching stage under high temperature and high-alkali condition, further bleach the bleached pulp of deriving by ligno-cellulosic materials, wherein, under the chlorine dioxide concentration of 1wt%-3wt%, carry out second chlorine dioxide bleaching stage (referring to patent documentation 4) based on the weight that parches of paper pulp.
According to nearest discovery, known not only conventional lignin and modified lignin, and also hexenuronic acid is the reason that causes ECF or TCF bleached pulp to fade.This hexenuronic acid is to produce by the methylglucuronic acid demethylation from hemicellulose during the boiling step.It is said that this hexenuronic acid is the reason that causes paper pulp to fade.The acid treatment of proposition under relatively-high temperature is to remove hexenuronic acid.According to this method, by under sour condition, at high temperature handle unbleached paper pulp, thereby remove hexenuronic acid and modified lignin.For example, a kind of technology is disclosed, wherein heating is by the suspension of the cellulose pulp of sulfuric acid process or alkaline process preparation, and handling under 85-150 ℃ and under the pH of about 2-5, removing in the cellulose pulp hexenuronic acid, thereby make the Kappa number of paper pulp reduce 2-9 unit's (referring to patent documentation 5) at least about 50%.
MP has and reaches even the pulp yield of 90-95%, because they become fiber to prepare by pulverizing the wood pulp fragment.Therefore, in order effectively to utilize the forest reserves, wish to enlarge the purposes of MP.Yet MP causes being mainly used in mechanical paper and newsprint owing to fade significantly, and only partly is used for application such as the printing paper and the record-paper of high whiteness of requirement and long shelf life at present.The variable color that fade mechanism and lignin in above-described paper pulp in MP induced is identical, but fading than more serious in CP and the SCP in MP because with in CP and SCP, compare, in MP, have the lignin and the modified lignin of higher residual quantity.The main cause of strong variable color is the oxidized quinhydrones that produced of lignin in the hydrogen peroxide bleaching process in the MP, and quinhydrones is oxidized to quinone easily.It is more serious to fade in having the MP of higher whiteness, and this is because produce more quinhydrones under the bleaching of higher degree.The not oxidation lignin that remains in the MP excites under ultraviolet light and oxidative degradation equally, produces hydroquinone compound in new ways, thereby causes fading.Therefore, the principal element of seriously fading in MP is a hydroquinone compound, and if can degrade this hydroquinone compound in advance, then can greatly be reduced in seriously fading in the MP, and can expect that many advantages contain the steady quality of the paper of MP at present as (1), (2) be rich in MP because fading in MP causes having in the present paper product of limited MP content, (3) can develop the new product that contains MP etc.
In order to solve the COLOR FASTNESS PROBLEM in MP, proposed many proposals for a long time, and shown the method (referring to non-patent literature 2) that is used in combination for example water-soluble ultraviolet absorber and light stabilizer recently.Also show the method (referring to non-patent literature 3) that wherein reduction is included in aromatic ring in the interior lignin of MP.Yet the shortcoming of ultraviolet absorber or analog is that their effect continues on section ground for a long time, because they are because of the ultraviolet light deterioration.On the other hand, when using rhodium catalyst also during the aromatic ring of protolignin, at room temperature, in aqueous alcohol solutions, in the hydrogenation of the aromatic ring in the lignin that from timber, separates, as if need cost reach 5 days time partial hydrogenation aromatic ring, and this catalyst is very difficult to directly and is present in direct intrastitial lignin reaction, this is because it uses with the form of emulsion.Therefore, at present, all these conventional methods have such as shortcomings such as anti-fading effect deficiency, long processing time, uneconomical or practicalities.
One of applicant of the present invention, Independent Administrative Leged Industrial Technology Complex Inst (National Institute of Advanced Industrial Science and Technology), with regard to dioxde pulp bleaching process, comprising with ultraviolet and/or visible light irradiation, three patent applications have been applied for.Specifically, a kind of technology is disclosed, comprising in using the reductant bleached pulp, with ultraviolet and/or visible light irradiation (referring to patent documentation 6).Another technology is disclosed, comprising at the organic peroxide of using ROOR ' expression as in the presence of the oxidant, usefulness ultraviolet and/or visible light irradiation (referring to patent documentation 7).The another technology (referring to patent documentation 8) that is used in combination hydrogen peroxide and ultraviolet and/or visible light is disclosed.The present invention is applied on the bleached pulp by the technology with these existing inventions, improves the method for paper pulp fadedness.
Non-patent and the patent documentation of quoting as prior art is as follows herein:
The Bleaching of Pulp, P382, P384, TAPPI PRESS (1979), N.Hartler, TAPPI 43 (11) 903 (1960) (non-patent literature 1); Japan Patent No.1983064 (patent documentation 1); Japan Patent No.2115315 (patent documentation 2); JPA HEI6-101185 (patent documentation 3); JPA HEI 9-105091 (patent documentation 4); JPA HEI10-508346 (patent documentation 5); Yuan, z. etc., J.Pulp Paper Sci., 28 (5), 159 (2002) (non-patent literatures 2); Hu, T.Q. etc., J.Pulp Paper Sci., 25 (9), 312 (1999) (non-patent literatures 3); JPA 2002-88671 (patent documentation 6); JPA 2002-88672 (patent documentation 7); JPA 2002-88673 (patent documentation 8).
Disclosure of the Invention
The purpose of this invention is to provide the method for improving the paper pulp fadedness, it is characterized in that:
(1) can be suitable for the omnipotent technology of any kind paper pulp;
(2) time-saving technology;
(3) remarkable and permanent anti-fading effect;
(4) environmental friendliness, and do not have offensive odour or toxicity;
With other performance, and provide the fadedness that obtains by the described method of improving fadedness to obtain the paper pulp of very big improvement.
Can be selected from additive in reductant, peroxide and the hydrogen supply organic compound in two or more mixture of one of CP, SCP, MP and DIP of bleaching or they by adding one or more, and with ultraviolet and/or visible light irradiation, thereby greatly improved the fadedness of paper pulp.
The accompanying drawing summary
Fig. 1 is the chart that shows that the anti-fading effect based on whiteness changed with the laser irradiation time.
Fig. 2 is the chart that shows that the anti-fading effect based on whiteness changes with optical maser wavelength.
Fig. 3 is the chart that shows that the anti-fading effect based on the L*a*b* aberration changed with the laser irradiation time.
Fig. 4 is the chart that shows that the anti-fading effect based on the L*a*b* aberration changes with optical maser wavelength.
The preferred embodiments of the invention
The paper pulp that is suitable for improving fadedness according to the present invention comprises common bleaching CP, SCP, MP and the DIP that is derived from timber.Can use any in these paper pulp or two or more mixture wherein.Term " bleaching " is meant that herein CP had for example carried out the bleaching process of normal multistep bleaching or short sequence.
The particular compound that can use in the present invention comprises known reductant, peroxide and the hydrogen supply organic compound as bleaching/decolourant.Pulp treatment in the presence of at least a compound in these compounds.
This reductant comprises for example inferior sulfate radical or bisulfite (bisulfite) ion, dithionite (hydrosulfite), hydrogenated boron compound etc.Hydrogenated boron compound is usually with following general formula (1) or (2) expression:
M(BR
4-nH
n)
m (1)
N=integer 1-4 wherein, m=integer 1-3, M=metal ion, organic ion or inorganic ions, R=alkyl or substituted hydrocarbon radical or
BR
3-nH
n (2)
N=integer 1-3 wherein, R=alkyl or substituted hydrocarbon radical.
In above general formula (1), metal ion intends comprising valent metal ion such as alkali metal, bivalent metal ion such as alkaline-earth metal, and trivalent metal ion; And organic ion can be any stable a kind of, particularly quaternary ammonium ion.Substituent R comprises and preferably contains 1-20, and more preferably the aliphatic hydrocarbyl of 1-10 carbon atom preferably contains 6-20, and more preferably the aromatic hydrocarbyl of 6-14 carbon atom preferably contains 7-40, more preferably substituted hydrocarbon radical of 7-24 carbon atom etc.When having two or more substituent R, R can be identical or different.Being used for particularly preferred hydrogenated boron compound of the present invention is sodium borohydride and hydroboration tetrabutylammonium.
About peroxide, can use organic peroxide and inorganic peroxide the two.Spendable organic peroxide is the compound of following general formula (3) expression:
ROOR’ (3)
Wherein R and R ' can be identical or different, expression alkyl, alkyl-carbonyl, aryl carbonyl, alkoxy carbonyl, aryloxycarbonyl, formoxyl or hydrogen.
Alkyl comprises aromatic hydrocarbyl such as phenyl, naphthyl, xenyl and anthryl; Aliphatic hydrocarbyl; And replacement form; Alkyl-carbonyl comprises acetyl group, ethyl carbonyl and propiono carbonyl and replacement form thereof; Aryl carbonyl comprises benzoyl, naphthyl carbonyl and xenyl carbonyl and replacement form thereof; Alkoxy carbonyl comprises methoxycarbonyl and ethoxy carbonyl and replacement form thereof; Aryloxycarbonyl comprises phenyloxycarbonyl, naphthoxy carbonyl and xenyl oxygen base carbonyl and replacement form thereof.R and R ' can be identical or different.The instantiation of these organic peroxides comprises for example peracid such as benzylhydroperoxide and derivative, peracetic acid and performic acid; The ester of these peracid; With percarbonic acid and ester thereof.Inorganic peroxide comprises hydrogen peroxide, sodium peroxide etc.
The primary alconol of preferred following general formula (4) expression of hydrogen supply organic compound, and specifically, comprise ethanol, phenmethylol, furfuryl alcohol etc.:
RCH
2OH (4)
Wherein R represents alkyl, aryl etc.
In the present invention, reductant, peroxide and hydrogen supply organic compound can use separately under the situation that does not have solvent, but should be requiredly so that dispersion liquid in ultraviolet and/or the permeable solvent of visible light or solution form are being used.This solvent comprises separately or the water, alcohol, straight chain or cyclic alkane, the ether etc. that mix, preferred water.
Be not specifically limited the consumption of employed reductant, peroxide and hydrogen supply organic compound, as long as it is in the saturated concentration place of this compound in solvent or following, but in solvent, be preferably 0.01-40% (weight/volume), more preferably 0.1-20%.The consumption of employed any reductant, peroxide and hydrogen supply organic compound is the 0.05-50% solid weight based on the paper pulp solid, more preferably the 0.1-25% solid weight.
Be not specifically limited ultraviolet and/or visible light, but use about 180-800nm requiredly, the wavelength of preferred 200-500nm.This is because lignin, paraquinones and o-quinone have the maximum absorption wavelength of 280nm, 360nm and 390-410nm respectively.Suitable light source comprises common light source such as low pressure mercury lamp, high-voltage mercury lamp and xenon lamp; And various Excimer lamps and various laser; But consider high speed processing, use LASER Light Source requiredly.Be not specifically limited LASER Light Source, and laser can be pulse or continuous, but preferably uses second and the third harmonic etc. of PRK (ArF PRK, KrF PRK, XeCl PRK, XeF PRK etc.), argon laser, krypton ion laser, YAG laser.
Be not specifically limited irradiation intensity, but, be 0.1mJ/cm suitably for pulsed irradiation
2/ subpulse-1.0kJ/cm
2/ subpulse, and, be 0.1mW-10kw/cm for continuous irradiation
2Also be not specifically limited irradiation temperature, but be preferably-80 ℃-100 ℃, more preferably 0 ℃-80 ℃.Consider the quality that is included in the potential coloring material in the raw material paper pulp, the ultraviolet of the type of additive or solvent and concentration and irradiation and/or the type of visible light and intensity, thus determine exposure time suitably, but common 1-60 minute is enough.
The present invention is not limited specifically to any embodiment, and condition is, at least a compound that is selected from reductant, peroxide and the hydrogen supply organic compound in (1) bleached pulp and (2) is contacted, and with (3) ultraviolet and/or visible light irradiation.According to an embodiment preferred, for example, (1) raw material paper pulp be dispersed in contain (2) at least a be selected from reductant, peroxide and the hydrogen supply organic compound compound and in ultraviolet and/or the permeable solvent of visible light, use (3) ultraviolet and/or visible light irradiation then.Specifically, when solvent is water, the aqueous suspension of the paper pulp that had carried out bleaching and discharged from blanching step combines with at least a compound that is selected from reductant, peroxide and the hydrogen supply organic compound and mixes, and uses ultraviolet and/or visible light irradiation then.Perhaps, (1) raw material paper pulp is formed sheet material or thin layer, with containing (2) at least a solvent impregnated described sheet material or thin layer that is selected from the compound in reductant, peroxide and the hydrogen supply organic compound, use (3) ultraviolet and/or visible light irradiation then then.Specifically, when solvent is water, the aqueous suspension of the paper pulp that had carried out bleaching and discharged from blanching step is dehydrated into the paper pulp sheet material by the device such as paper pulp sheet material machine, flood described paper pulp sheet material with at least a compound that is selected from reductant, peroxide and the hydrogen supply organic compound then, and with ultraviolet and/or visible light irradiation.
Know that we think as follows although the anti-mechanism of fading according to the present invention is also not quite clear.That is to say, according to the present invention, be included in the potential coloring material in the paper pulp, as the lignin in MP, by using ultraviolet and/or visible light irradiation, oxidized degraded produces quinhydrones in bleaching process.Unoxidized unmodified lignin residual in bleaching process produces various quinones.The present invention utilizes following phenomenon: wherein these quinones are by ultraviolet and/or visible light, be energized into excitation state from the ground state electricity, the result changes into the state with active more material, thereby improve and at least a reaction that is selected from the compound in reductant, peroxide and the hydrogen supply organic compound that coexists, with the degradation reaction of promotion coloring material or the hydrogenation of two keys; Or it is opposite, utilize following phenomenon: wherein at least aly be selected from compound in reductant, peroxide and the hydrogen supply organic compound by change into more active material with ultraviolet and/or visible light irradiation, thereby the reactivity of improvement and coloring material is with the degradation reaction of raising coloring material or the hydrogenation of two keys.
As the method that arrives the paper inner control fadedness of making by MP by blast blending such as mercaptan compound, this method and offensive odour and high toxicity are relevant, and do not cause basic improvement, because this method only promotes quinone to become the reaction of quinhydrones, in case and additive is consumed alkane, can fade because of ultraviolet light causes, opposite with the method that is proposed before this, the present invention improves the method for fadedness, by adopting unique mode, promptly at least a reductant that is selected from, compound in peroxide and the hydrogen supply organic compound exists down, with ultraviolet and/or visible light irradiation, not only address all of these issues fully, and aspect environmental friendliness, have unusual advantage.
Embodiment
Following embodiment sets forth the present invention in further detail, yet, do not limit the present invention.
[embodiment 1]
Proportional by containing of pine manufacturing is 1: 1 bleaching MP and the hand-made paper (200cm of bleaching CP
2, Substance 60g/m
2) be divided into four parts, be used for the sample of laser treatment with preparation.These samples are immersed in 6% sodium borohydride aqueous solution (w/v), are fixed on the glass plate then.This moment, based on the weight of paper pulp solid, the pickup of sodium borohydride is 18% solid weight.With the KrF PRK at 40mJ/cm
2Irradiation sample is 10 minutes under/subpulse, the 5Hz.After finishing laser irradiation, wash sample with water and drying in drum dryer.Use xenon lamp weather meter, carry out color fading test.The ultraviolet light irradiation sample that generates with xenon lamp 0.5,1.0 and 2.0 hours is measured ISO whiteness [JIS 8148] and L*a*b* aberration (Δ E*ab) [JIS Z8701] afterwards.Under the irradiation intensity of 63 ℃ black side plate temperatures, 50% humidity and 70W, carry out color fading test.
[embodiment 2]
Carry out the operation identical with embodiment 1, different is becomes 20 minutes with the exposure time of KrF PRK.
[embodiment 3]
Carry out the operation identical with embodiment 1, different is becomes 40 minutes with the exposure time of KrF PRK.
[embodiment 4]
Carry out the operation identical with embodiment 2, different is to use the XeCl PRK to substitute the KrF PRK.
[Comparative Examples 1]
Laser treatment sample among the dipping embodiment 1 in water, dry in drum dryer then, and carry out color fading test.
[Comparative Examples 2]
Carry out the operation identical with embodiment 2, different is not have under the situation of laser irradiation, and sample was left standstill 20 minutes.
Fig. 1-4 shows the result.
[embodiment 1]
Proportional by containing of pine manufacturing is 1: 1 bleaching MP and the hand-made paper (200cm of bleaching CP
2, Substance 60g/m
2) be divided into four parts, be used for the sample of laser treatment with preparation.These samples are immersed in 6% sodium borohydride aqueous solution (w/v), are fixed on the glass plate then.This moment, based on the weight of paper pulp solid, the pickup of sodium borohydride is 18% solid weight.With the KrF PRK at 40mJ/cm
2Irradiation sample is 10 minutes under/subpulse, the 5Hz.After finishing laser irradiation, wash sample with water and drying in drum dryer.Use xenon lamp weather meter, carry out color fading test.The ultraviolet light irradiation sample that generates with xenon lamp 0.5,1.0 and 2.0 hours is measured ISO whiteness [JIS 8148] and L*a*b* aberration (Δ E*ab) [JIS Z8701] afterwards.Under the irradiation intensity of 63 ℃ black side plate temperatures, 50% humidity and 70W, carry out color fading test.
[embodiment 2]
Carry out the operation identical with embodiment 1, different is becomes 20 minutes with the exposure time of KrF PRK.
[embodiment 3]
Carry out the operation identical with embodiment 1, different is becomes 40 minutes with the exposure time of KrF PRK.
[embodiment 4]
Carry out the operation identical with embodiment 2, different is to use the XeCl PRK to substitute the KrF PRK.
[Comparative Examples 1]
Laser treatment sample among the dipping embodiment 1 in water, dry in drum dryer then, and carry out color fading test.
[Comparative Examples 2]
Carry out the operation identical with embodiment 2, different is not have under the situation of laser irradiation, and sample was left standstill 20 minutes.
Fig. 1-4 shows the result.
The result shows along with exposure time increases, fades and is inclined to descend (Fig. 1,3) when with KrF PRK irradiation MP.Especially,, compare with blank with laser irradiation 40 minutes sample, after color fading test 2 hours, demonstrate considerably less fade and 16 remarkable whiteness poor.Comparative result between the anti-fading effect of KrF PRK and XeCl PRK shows observes considerably less difference (Fig. 2,4) between them.
Advantage of the present invention
By the new method of improving the paper pulp fadedness is provided, wherein said method is included at least one It is lower to plant the compound existence that is selected from reducing agent, peroxide and the hydrogen supply organic compound, with purple Outer and/or visible light irradiation paper pulp can be processed the paper pulp of any type rapidly, produce significantly and Permanent anti-fading effect, and other advantage are such as environmental friendliness. In addition, by the present invention Improving paper pulp that fadedness that the method for fadedness obtains obtained very big improvement can be used as raw material and produces Give birth to further advantage such as paper product steady quality, develop new product, the expansion of MP uses Deng.
Claims (4)
1. the improvement method of a paper pulp fadedness is characterized in that, in the presence of at least a compound that is selected from reductant, peroxide and the hydrogen supply organic compound, with ultraviolet and/or visible light irradiation paper pulp.
2. the improvement method of the paper pulp fadedness of claim 1 is characterized in that, paper pulp is a kind of in semichemical wood pulp, bleached chemical paper pulps and the bleaching de inked pulp of bleaching mechanical pulp, bleaching or two or more the mixture in them.
3. the improvement method of claim 1 or 2 paper pulp fadedness is characterized in that ultraviolet and/or visible light are laser.
4. the paper pulp that is improved of the fadedness that obtains by claim 1,2 or 3 any one the improvement methods of paper pulp fadedness.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP323718/2002 | 2002-11-07 | ||
| JP2002323718 | 2002-11-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1720369A true CN1720369A (en) | 2006-01-11 |
Family
ID=32310422
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2003801048629A Pending CN1720369A (en) | 2002-11-07 | 2003-11-07 | Method for improving the discoloration resistance of pulp and pulp improved in discoloration resistance |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US20060207732A1 (en) |
| EP (1) | EP1568819A1 (en) |
| JP (1) | JPWO2004042139A1 (en) |
| CN (1) | CN1720369A (en) |
| AU (1) | AU2003277614A1 (en) |
| CA (1) | CA2505018A1 (en) |
| WO (1) | WO2004042139A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103328716A (en) * | 2010-11-16 | 2013-09-25 | 王子控股株式会社 | Cellulose fiber assembly and production method for same, fibrillated cellulose fiber and production method for same, and cellulose fiber complex |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2415135A (en) * | 2004-06-15 | 2005-12-21 | Reckitt Benckiser | Improvements in and relating to depilatory compositions |
| WO2006110751A1 (en) * | 2005-04-08 | 2006-10-19 | Nalco Company | Improved composition and processes for paper production |
| FI20085345L (en) * | 2008-04-22 | 2009-10-23 | Kemira Oyj | Method for reducing light-induced yellowing in lignin-containing material |
| JP6167342B2 (en) * | 2013-03-28 | 2017-07-26 | 株式会社エクォス・リサーチ | Method for saccharification of cellulose |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE383007B (en) * | 1973-03-02 | 1976-02-23 | Svenska Cellulosa Ab | METHOD OF PRODUCING SURFACE TREATED PAPER IN THE FORM OF A CONTINUOUS PATH |
| US4294654A (en) * | 1980-03-21 | 1981-10-13 | International Paper Company | Delignification and bleaching of lignocellulosic pulp via photo-oxygenation |
| EP0112377B1 (en) * | 1982-06-24 | 1986-11-12 | Scott Paper Company | Ozone bleaching of cellulosic materials |
| FI90680C (en) * | 1992-04-24 | 1994-03-10 | Kymin Paperiteollisuus Oy | Bleaching of paper web with peroxide |
| JP2593392B2 (en) * | 1992-10-20 | 1997-03-26 | 本州製紙株式会社 | Pulp bleaching method |
| JP3368336B2 (en) * | 2000-06-20 | 2003-01-20 | 独立行政法人産業技術総合研究所 | Pulp bleaching method |
| JP3371228B2 (en) * | 2000-06-20 | 2003-01-27 | 独立行政法人産業技術総合研究所 | Pulp bleaching method |
| JP3787612B2 (en) * | 2000-06-20 | 2006-06-21 | 独立行政法人産業技術総合研究所 | Pulp bleaching method |
-
2003
- 2003-11-07 CN CNA2003801048629A patent/CN1720369A/en active Pending
- 2003-11-07 WO PCT/JP2003/014209 patent/WO2004042139A1/en active Application Filing
- 2003-11-07 US US10/533,657 patent/US20060207732A1/en not_active Abandoned
- 2003-11-07 EP EP03810657A patent/EP1568819A1/en not_active Withdrawn
- 2003-11-07 CA CA002505018A patent/CA2505018A1/en not_active Abandoned
- 2003-11-07 AU AU2003277614A patent/AU2003277614A1/en not_active Abandoned
- 2003-11-07 JP JP2004549641A patent/JPWO2004042139A1/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103328716A (en) * | 2010-11-16 | 2013-09-25 | 王子控股株式会社 | Cellulose fiber assembly and production method for same, fibrillated cellulose fiber and production method for same, and cellulose fiber complex |
| CN105672023A (en) * | 2010-11-16 | 2016-06-15 | 王子控股株式会社 | Cellulose fiber assembly and production method for same, fibrillated cellulose fiber and production method for same, and cellulose fiber complex |
Also Published As
| Publication number | Publication date |
|---|---|
| AU2003277614A1 (en) | 2004-06-07 |
| WO2004042139A1 (en) | 2004-05-21 |
| JPWO2004042139A1 (en) | 2006-04-06 |
| US20060207732A1 (en) | 2006-09-21 |
| EP1568819A1 (en) | 2005-08-31 |
| AU2003277614A8 (en) | 2004-06-07 |
| CA2505018A1 (en) | 2004-05-21 |
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