CN100591842C - Method for reducing the extractives content of high-yield pulps and method for producing bleached high-yield pulps - Google Patents
Method for reducing the extractives content of high-yield pulps and method for producing bleached high-yield pulps Download PDFInfo
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- CN100591842C CN100591842C CN200580005933A CN200580005933A CN100591842C CN 100591842 C CN100591842 C CN 100591842C CN 200580005933 A CN200580005933 A CN 200580005933A CN 200580005933 A CN200580005933 A CN 200580005933A CN 100591842 C CN100591842 C CN 100591842C
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- pulp
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- surface active
- ionic surface
- bleaching
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Classifications
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- 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
- D21C9/08—Removal of fats, resins, pitch or waxes; Chemical or physical purification, i.e. refining, of crude cellulose by removing non-cellulosic contaminants, optionally combined with bleaching
-
- 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
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
-
- 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
- D21C9/1036—Use of compounds accelerating or improving the efficiency of the processes
Abstract
The invention relates to a method for reducing the content of extractives of a high-yield pulp in a peroxide bleaching stage, said stage including peroxide bleaching and a subsequent dewatering or washing, said method comprising contacting the pulp in the peroxide bleaching with an organic stabilizer and in or after the peroxide bleaching with a surfactant, and thereafter subjecting the bleached pulp to said dewatering or washing for removing extractives along with the aqueous phase. The invention also relates to a method for producing bleached high-yield pulp.
Description
Invention field
The present invention relates to reduce the method for the extractives content of high yield mechanical pulp.The invention still further relates to the method for the high-yield pulp of the bleaching of producing the extractives content with reduction.
DESCRIPTION OF THE PRIOR ART
Extract is the timber of available organic solvent extraction and the principal component in the pulp matter.The topmost chemical group of finding in extract is fat and resin acid, terpenes, phytosterol and phenolic compound.The discovery extract is esterification, saccharification and non-derivative form.The most problematic extract mainly is a lipophilic cpd in timber.They are aliphatic acid, resin acid, terpenes and sterol, and their function is by preventing that attacks such as fungi, bacterium from protecting trees.Leather leaf cork contains the 1.5% weight extract of having an appointment, and temperate zone hardwood contains 2-2.5% weight usually.In general, debatable extract usually is called as wood pitch.Usually in the high shear force zone and when the change in concentration of temperature, pH or wood pitch, pinpoint the problems.
Common adverse effect from wood pitch in zones of different is as described below.In the bleaching plant, form deposit, and also can increase the consumption of chemicals.In final products, find the extract of spot and high-load.
The modern bleaching process of mechanical pulp usually comprises the peroxide bleaching (PHC) of high-consistency.After peroxide bleaching,, make the pulp slurry dehydration afterwards usually with the plain boiled water diluted pulp that comes from paper machine.This washing step reduces the anionic trash that is carried in the paper machine, and also allows residual peroxide circulation.The alkaline peroxide oxidizes extract is also removed extract quite effectively from paper pulp.Yet, if in the bottom of PHC bleaching tower or the paper pulp after PCH bleaching dilute with plain boiled water, can in the surface of paper pulp or process equipment, precipitate extract again, this is because hang down pH, high rigidity or dielectric (salt) concentration of water causing.The extract of precipitation is transferred on the paper machine in fiber surface, thereby causes the problem of green end and paper quality.When the recirculation of PHC wash filtrate is got back in the early stage workshop section of this technology, the extract that may in wash filtrate, find can be in process equipment or fiber in acidity or neutral environment precipitation again.
US4363699 discloses the method for the aqueous slkali of the employed peroxide compound of stable bleaching, and the wherein poly-acrylic acid basic salt of Alpha-hydroxy joins in the solution as stabilizing agent.Stable solution can be used for bleached pulp and textiles.When the bleaching textiles, liquid lime chloride can contain wetting agent (it is a kind of surfactant).
US4963157 discloses a kind of the hydrogen peroxide bleaching cellulosic fibre material of using, particularly Mian method.This method comprises with the liquid lime chloride impregnation of fibers material that contains peroxide and stabilizing agent.Stabilizing agent comprises poly-Alpha-hydroxy acrylic acid or its salt or its corresponding polylactone and organic phospho acid or its salt.
DE3423452 discloses the solution of avoiding using waterglass, and it comprises the mixture of the copolymer of the water-soluble homopolymer of poly-Alpha-hydroxy acrylic acid (PHAA) and acrylic or methacrylic acid or acrylic acid and/or maleic acid.Be mixed together salt, particularly the sodium salt of the sodium salt of PHAA and polycarboxylic acid polymer.Chelating agent can be joined in this mixture, so obtain to be used for the improved stabilizing agent of bleaching process.According to DE3423452, contain the alkaline peroxide bleaching liquid of described stabilized mixture by use, thereby carry out bleaching process.
Summary of the invention
The present invention is based on the following fact: under alkali condition, extract is more solvable, therefore when using dilution water, when for example bleaching plain boiled water diluted pulp afterwards, particularly when the pH of dilution water was lower than the pH of the paper pulp that flows out from bleaching tower, extract can be deposited on the fiber surface again.According to the present invention, find that some surfactants can suppress the precipitation of extract, and therefore they are remained in the water.Then, can wash out extract from paper pulp at next extruder place of dewatering, this causes the extractives content of reduction in the paper pulp then.Because extract is disperseed to be stabilized with particle, therefore when filtrate is recycled in the early stage process section, there is not the precipitation again of extract.
When do not using silicate as the situation of stabilizing agent under during bleached pulp, the present invention is particularly advantageous, this is because notice that silica has certain dispersion effect to extract.Yet the present invention also is good when operating in the presence of silicate.
Detailed Description Of The Invention
According to the present invention, be provided at the method that reduces the extractives content of high-yield pulp in the peroxide bleaching workshop section, described workshop section comprises peroxide bleaching and dehydration subsequently or washing, described method is included in paper pulp is contacted with organic stabilizer, and among peroxide bleaching or afterwards, contact with surfactant, afterwards bleached pulp is carried out described dehydration or washing so that remove extract with water.
In the context of the present invention, peroxide bleaching workshop section comprises peroxide bleaching paper pulp, diluted pulp randomly, and make dewatering of pulp or washing.
According to the present invention, the method of the high-yield pulp of the bleaching of producing the extractives content decline also is provided, this method comprises uses the peroxide bleaching high-yield pulp, wherein in the peroxide bleaching process, paper pulp contacts with organic stabilizer, with in the peroxide bleaching process or after peroxide bleaching, contact with surfactant, and make bleached pulp dehydration or washing so that remove extract and produce the high-yield pulp of the bleaching that the extractives content descends with water.
The extract of removing from paper pulp of the present invention derives from wood pitch.Extract comprises aliphatic acid, resin acid, terpenes, phytosterol and the phenolic compound of esterification, saccharification and/or non-derivative form.The most debatable extract comprises aliphatic acid, resin acid, triglycerides, s t eryl ester, sterol and lignan.
Organic stabilizer and surfactant can be added independently, perhaps these chemicals and liquid lime chloride can be mixed in advance.In addition, can simultaneously or typically as a kind of chemical mixture, promptly product adds organic stabilizer and surfactant.
Can organic stabilizer and surfactant be joined in the paper pulp among the peroxide bleaching or before peroxide bleaching.
Also can after peroxide bleaching, surfactant be joined in the paper pulp.In the case, surfactant can be joined in the dilution water, described dilution water joins in the paper pulp between peroxide bleaching and dehydration or washing.Dilution water can be the plain boiled water that circulates from paper machine.
Employed in the methods of the invention organic peroxide stabilizing agent is polymer stabilizer preferably, for example poly-alpha-hydroxy acrylic acid or its salt or polylactone accordingly, the homopolymers of acrylic acid, methacrylic acid or maleic acid, the perhaps copolymer of acrylic acid and/or methacrylic acid and unsaturated dicarboxylic.Polymer stabilizer also can be the mixture of poly-alpha-hydroxy acrylic acid and this homopolymers and/or this copolymer.Unsaturated dicarboxylic is maleic acid preferably.The acrylic acid salt of poly-alpha-hydroxy is sodium, potassium or ammonium salt preferably.The acrylic acid molecular weight of poly-alpha-hydroxy can be at least 5000, preferably at least 10000 and more preferably at least 15000 (sodium-salt form with PHAA calculates).The molecular weight of homopolymers and copolymer can be at least 4000, preferably at least 10000 and more preferably at least 20000.
Organic stabilizer also can be phosphonic acids or its salt.Salt is sodium, potassium or ammonium salt preferably.Suitable phosphonic acids for example is (many) aminophosphonic acids, for example amino three (methylene phosphonic acids), ethylene diamine four (methylene phosphonic acid), i.e. EDTMPA or diethylenetriamines five (methylene phosphonic acid), i.e. DTPMPA.
Except described organic stabilizer, also can introduce another kind of stabilizing agent.This another kind stabilizing agent can be an alkaline earth metal compound, for example magnesium and/or calcium compound.Alkaline earth metal compound can be a salt, and for example, sulfate, chloride or any other water soluble salt form are perhaps with the complex form of polymer or chelating agent.Preferred alkali salt is a magnesium sulfate.
In dry pulp per ton, the consumption of organic stabilizer is preferably 0.1kg-5kg, more preferably in dry pulp per ton, for 0.25kg-3kg and even more preferably in dry pulp per ton, be 0.5kg-3kg.
Employed in the methods of the invention surfactant can be an anion surfactant, for example naphthalene sulfonate or lignosulphonates, perhaps non-ionic surface active agent, for example O/W emulsifying agent, for example alcohol ethoxylate or alkyl phenol ethoxylate.
Also can use the mixture of anion and non-ionic surface active agent.But the mating surface activating agent uses defoamer, to prevent foaming.
In dry pulp per ton, the consumption of surfactant is preferably 0.005kg-2kg, more preferably in dry pulp per ton, is 0.05kg-1kg.
At bleaching high yield mechanical pulp, for example use method of the present invention in ground wood pulp, Stone Ground Wood and pressure ground wood pulp (GW, SGW, PGW), mill mechanical pulp (RMP), hot method mechanical pulp (TMP) and the chemical thermomechanical paper pulp (CTMP, APMP).
In peroxide bleaching, hydrogen peroxide is preferably used as bleaching agent.Can in bleaching, use other chemicals, for example bleaching stibilizer, chelating agent and/or magnesium sulfate.Particularly advantageous is before bleaching, perhaps when using bleaching chemical, to add chemicals.If have several bleacheries, then can in any one bleachery or in several workshop sections, add chemicals.
The time of staying in bleaching can change in wide region, and for example 30-240 minute, preferred 45-180 minute and most preferably 60-120 minute.The time of staying is also depended on employed temperature in bleaching.
Can under 30-90 ℃ temperature, preferably under 50-90 ℃ temperature, carry out the bleaching of high-yield pulp.Can bleach under the denseness selecting, but most preferably under high-consistency, promptly bleach more than or equal to about 30% time.Also can between each section, have in two sections of dewatering period and bleach.
In alkali bleaching of the present invention, pH can be 7-14, preferred 8-11.Alkali, NaOH typically can change in wide region with the ratio of peroxide, and this depends on raw material and bleaching degree.Also can use can be for the alkali source that substitutes, for example sodium carbonate.
Set forth the present invention by following embodiment.Except as otherwise noted, percentage is % weight." kg/t " is meant the kilogram number in dry pulp per ton." Cs " is meant denseness." P " represents peroxide workshop section.
Embodiment
Comparative Examples
The purpose of this Comparative Examples is a clarification problem to be solved by this invention.Use waterglass or poly-alpha-hydroxy acrylic acid brine (PHAA) as stabilizing agent, with the TMP paper pulp (dragon spruce) of peroxide bleaching high-consistency.Subsequently, use the ion exchange water diluted pulp, be dewatered to 30% denseness then.The detailed experiments data have been shown in the following table.
After dilution, the high turbidity of filtrate is attributable to extract.To the analysis showed that of extract, most of extract is removed in bleaching.The result shows that silicate (waterglass) has certain dispersibility to extract, and this is because under the situation that adopts the acrylates based stabilizer, the extractives content is much higher.This means particularly do not containing under the bleaching situation of silicate that pitch dispersants is favourable.
Embodiment 1
Take out CTMP-paper pulp (aspen) sample from grater, and arrive the brightness of 83-84%ISO with peroxide bleaching.Conditions of bleaching is as described below: t=120 minute, and 70 ℃, denseness 30%, H
2O
238kg/t, NaOH 21kg/t, Na
2CO
38kg/t.Paper pulp is chelated in grater, and manganese content is 1.5ppm, and Fe content is 5ppm.In peroxide bleaching workshop section, drop into additive, and after bleaching, under different pH levels, diluted pulp is to 10% denseness, subsequent dewatering.Following table shows the turbidity of filtrate after dehydration.Use dry pulp 2kg polymer per ton (poly-alpha-hydroxy acrylic acid brine) as stabilizing agent and 0.1kg naphthalene sulfonate+0.1kg non-ionic surface active agent (HLB 12.3 for alcohol ethoxylate 7mol EO, C12-C14), carry out experiment of the present invention.In the contrast experiment, waterglass and poly-alpha-hydroxy acrylic acid brine used as stabilizers.Under each situation, the consumption of bleaching results and chemicals is roughly the same.
| Waterglass, 25kg/t | Acrylate polymer, 2kg/t | The present invention |
| The pH turbidity, NTU | The pH turbidity, NTU | The pH turbidity, NTU |
| 6.6 1510 7.5 1430 7.8 1465 | 6.3 1353 7.3 1317 7.7 1389 | 6.5 1464 7.2 1440 7.5 1481 |
Can find out that according to this result the silica that comes from waterglass (sodium metasilicate) increases turbidity.This is attributable to higher the extractives content in the filtrate.When with polymer-based stabilizer substituted for silicon hydrochlorate, turbidity is lower, and the extractives content is higher in the paper pulp.Chemical composition that according to the present invention obtains higher turbidity, and the extract that this proof is dissolved in the alkaline peroxide does not precipitate after dilution again.
Embodiment 2
Take out CTMP-paper pulp (aspen) sample from grater, and under high-consistency, use peroxide bleaching.Following table shows conditions of bleaching and result.In bleachery, add surfactant, and after bleaching, use the ion exchange water diluted pulp.The composition of surfactant is that weight ratio is 2: 1 a naphthalene sulfonic acids condensation product (Na salt) and alcohol ethoxylate (the same with last embodiment) (feeding intake with the dilution of 20% aqueous solution) herein.Polymer-based stabilizer is that activity substance content is 25% poly-alpha-hydroxy acrylic acid brine and mixture (1: 4 w: w) of maleate-acrylates copolymer.
* from paper pulp
DCM represents carrene.
The result shows that method of the present invention reduces the extract in the paper pulp and do not influence bleaching results.
Embodiment 3
Take out CTMP-paper pulp (aspen) sample from grater, and arrive the brightness of 83-84%ISO with peroxide bleaching.In peroxide bleaching workshop section, drop into additive, and after bleaching, under different pH levels, diluted pulp is to 10% denseness, subsequent dewatering.In an experiment, also after dilution, drop into surfactant additive.The result has been shown in the following table.Surfactant additive as used herein is naphthalene sulfonic acids condensation product (A) and alcohol ethoxylate (C16-C18, HLB 16 for B, 25mol EO).Polymer-based stabilizer is that activity substance content is 25% poly-alpha-hydroxy acrylic acid brine and mixture (1: 4 w: w) of maleate-acrylates copolymer.
The result shows that the combination of polymer-based stabilizer and anion and/or non-ionic surface active agent obtains lower the extractives content than waterglass.
Claims (20)
1. in peroxide bleaching workshop section, reduce the method for the extractives content of high-yield pulp, described workshop section comprises peroxide bleaching and dehydration subsequently or washing, described method is included in paper pulp is contacted with the organic polymer stabilizing agent, and among peroxide bleaching or afterwards, contact with anion or non-ionic surface active agent, paper pulp to bleaching carries out described dehydration or washing so that remove extract with water afterwards, wherein said organic polymer stabilizing agent is poly-alpha-hydroxy acrylic acid or its salt or corresponding polylactone, acrylic acid, the homopolymers of methacrylic acid or maleic acid, the perhaps copolymer of acrylic acid and/or methacrylic acid and unsaturated dicarboxylic, perhaps these mixture of polymers, and wherein said anion surfactant is naphthalene sulfonate or lignosulphonates, described non-ionic surface active agent is the O/W emulsifying agent, and described O/W emulsifying agent is alcohol ethoxylate or alkyl phenol ethoxylate.
2. the process of claim 1 wherein in peroxide bleaching organic polymer stabilizing agent and anion or non-ionic surface active agent are joined in the paper pulp.
3. the process of claim 1 wherein before peroxide bleaching organic polymer stabilizing agent and anion or non-ionic surface active agent are joined in the paper pulp.
4. the process of claim 1 wherein and after peroxide bleaching, anion or non-ionic surface active agent are joined in the paper pulp.
5. any one method of claim 1-4 wherein joins dilution water in the paper pulp between peroxide bleaching and dehydration or washing.
6. the method for claim 5 wherein joins anion or non-ionic surface active agent in the dilution water.
7. the process of claim 1 wherein that in dry pulp per ton the consumption of organic polymer stabilizing agent is 0.1kg-5kg.
8. the method for claim 7, wherein in dry pulp per ton, the consumption of organic polymer stabilizing agent is 0.25kg-3kg.
9. the process of claim 1 wherein that in dry pulp per ton the consumption of anion or non-ionic surface active agent is 0.005kg-2kg.
10. the method for claim 9, wherein in dry pulp per ton, the consumption of anion or non-ionic surface active agent is 0.05kg-1kg.
11. the method for the high-yield pulp of the bleaching that the production the extractives content descends, this method comprises uses the peroxide bleaching high-yield pulp, wherein in the peroxide bleaching process, paper pulp contacts with the organic polymer stabilizing agent, with in the peroxide bleaching process or after peroxide bleaching, contact with anion or non-ionic surface active agent, and make the dewatering of pulp or the washing of bleaching, so that remove extract and produce the high-yield pulp of the bleaching of the extractives content decline with water, wherein said organic polymer stabilizing agent is poly-alpha-hydroxy acrylic acid or its salt or corresponding polylactone, acrylic acid, the homopolymers of methacrylic acid or maleic acid, the perhaps copolymer of acrylic acid and/or methacrylic acid and unsaturated dicarboxylic, perhaps these mixture of polymers, and wherein said anion surfactant is naphthalene sulfonate or lignosulphonates, described non-ionic surface active agent is the O/W emulsifying agent, and described O/W emulsifying agent is alcohol ethoxylate or alkyl phenol ethoxylate.
12. the method for claim 11 wherein joins organic polymer stabilizing agent and anion or non-ionic surface active agent in the paper pulp in peroxide bleaching.
13. the method for claim 11 wherein joined organic polymer stabilizing agent and anion or non-ionic surface active agent in the paper pulp before peroxide bleaching.
14. the method for claim 11 wherein joins anion or non-ionic surface active agent in the paper pulp after peroxide bleaching.
15. any one method of claim 11-14 wherein joins dilution water in the paper pulp between peroxide bleaching and dehydration or washing.
16. the method for claim 15 wherein joins anion or non-ionic surface active agent in the dilution water.
17. the method for claim 11, wherein in dry pulp per ton, the consumption of organic polymer stabilizing agent is 0.1kg-5kg.
18. the method for claim 17, wherein in dry pulp per ton, the consumption of organic polymer stabilizing agent is 0.25kg-3kg.
19. the method for claim 11, wherein in dry pulp per ton, the consumption of anion or non-ionic surface active agent is 0.005kg-2kg.
20. the method for claim 11, wherein in dry pulp per ton, the consumption of anion or non-ionic surface active agent is 0.05kg-1kg.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI20040282 | 2004-02-24 | ||
| FI20040282A FI121385B (en) | 2004-02-24 | 2004-02-24 | Process for Reducing Extract Substance in High Yield Masses and Process for Preparing Bleached High Yield Masses |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1922359A CN1922359A (en) | 2007-02-28 |
| CN100591842C true CN100591842C (en) | 2010-02-24 |
Family
ID=31725758
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200580005933A Active CN100591842C (en) | 2004-02-24 | 2005-02-23 | Method for reducing the extractives content of high-yield pulps and method for producing bleached high-yield pulps |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US20070272378A1 (en) |
| EP (1) | EP1718801B1 (en) |
| CN (1) | CN100591842C (en) |
| AT (1) | ATE376094T1 (en) |
| BR (1) | BRPI0507851A (en) |
| CA (1) | CA2553662C (en) |
| DE (1) | DE602005002933T2 (en) |
| FI (1) | FI121385B (en) |
| WO (1) | WO2005080672A2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI20070126A0 (en) | 2006-09-08 | 2007-02-13 | Linde Ag | Process for de-pulping and using carbon dioxide or (bi) carbonate for this |
| WO2013178875A1 (en) * | 2012-05-29 | 2013-12-05 | Kemira Oyj | A process for the treatment of fibre material and a new composition |
| TW201610261A (en) | 2014-05-20 | 2016-03-16 | 喬治亞太平洋消費者產品公司 | Bleaching and shive reduction process for non-wood fibers |
| TW201610265A (en) | 2014-05-20 | 2016-03-16 | 喬治亞太平洋消費者產品公司 | Bleaching and shive reduction process for non-wood fibers |
| TW201544652A (en) * | 2014-05-20 | 2015-12-01 | Georgia Pacific Consumer Prod | Bleaching and shive reduction process for non-wood fibers |
| US11193237B2 (en) | 2017-09-11 | 2021-12-07 | Solenis Technologies, L.P. | Method for enhanced oxygen delignification of chemical wood pulps |
| WO2020093280A1 (en) * | 2018-11-07 | 2020-05-14 | Kemira Oyj | A composition for use as peroxide stabilizer |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4363699A (en) * | 1976-02-25 | 1982-12-14 | Solvay & Cie. | Process for stabilizing solutions of peroxidic compounds used for bleaching |
| CN1277285A (en) * | 1999-06-15 | 2000-12-20 | 杭州市化工研究所 | Resin obstruction controlling agent for paper making |
| CN1419621A (en) * | 2000-03-23 | 2003-05-21 | 赫尔克里士公司 | Pitch and stickies control in pulp and papermaking processes |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3423452A1 (en) * | 1984-06-26 | 1986-01-02 | Sandoz-Patent-GmbH, 7850 Lörrach | Stabilising mixture for the peroxide bleaching of cellulose-containing materials |
| US4963157A (en) * | 1987-04-17 | 1990-10-16 | Nippon Peroxide Co., Ltd. | Method for bleaching cellulosic fiber material with hydrogen peroxide |
| US5234544A (en) * | 1989-10-18 | 1993-08-10 | Air Products And Chemicals, Inc. | Cleaning and bleaching of secondary fiber |
| JP3191828B2 (en) * | 1992-05-27 | 2001-07-23 | 三菱瓦斯化学株式会社 | Deinking and bleaching of used printing paper |
| DE4344029A1 (en) * | 1993-12-23 | 1995-06-29 | Grillo Werke Ag | Copolymers of unsaturated carboxylic acids, process for their preparation and their use |
-
2004
- 2004-02-24 FI FI20040282A patent/FI121385B/en active IP Right Grant
-
2005
- 2005-02-23 DE DE602005002933T patent/DE602005002933T2/en active Active
- 2005-02-23 EP EP05717239A patent/EP1718801B1/en active Active
- 2005-02-23 WO PCT/FI2005/000112 patent/WO2005080672A2/en active IP Right Grant
- 2005-02-23 BR BRPI0507851-2A patent/BRPI0507851A/en not_active IP Right Cessation
- 2005-02-23 US US10/590,297 patent/US20070272378A1/en not_active Abandoned
- 2005-02-23 CN CN200580005933A patent/CN100591842C/en active Active
- 2005-02-23 CA CA2553662A patent/CA2553662C/en active Active
- 2005-02-23 AT AT05717239T patent/ATE376094T1/en not_active IP Right Cessation
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4363699A (en) * | 1976-02-25 | 1982-12-14 | Solvay & Cie. | Process for stabilizing solutions of peroxidic compounds used for bleaching |
| CN1277285A (en) * | 1999-06-15 | 2000-12-20 | 杭州市化工研究所 | Resin obstruction controlling agent for paper making |
| CN1419621A (en) * | 2000-03-23 | 2003-05-21 | 赫尔克里士公司 | Pitch and stickies control in pulp and papermaking processes |
Also Published As
| Publication number | Publication date |
|---|---|
| US20070272378A1 (en) | 2007-11-29 |
| FI20040282A (en) | 2005-08-25 |
| FI121385B (en) | 2010-10-29 |
| CN1922359A (en) | 2007-02-28 |
| EP1718801A2 (en) | 2006-11-08 |
| EP1718801B1 (en) | 2007-10-17 |
| DE602005002933D1 (en) | 2007-11-29 |
| ATE376094T1 (en) | 2007-11-15 |
| CA2553662A1 (en) | 2005-09-01 |
| DE602005002933T2 (en) | 2008-07-24 |
| CA2553662C (en) | 2012-10-23 |
| WO2005080672A3 (en) | 2005-12-08 |
| WO2005080672A2 (en) | 2005-09-01 |
| FI20040282A0 (en) | 2004-02-24 |
| BRPI0507851A (en) | 2007-07-10 |
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