EP0394368A1 - Procede de production de papier. - Google Patents

Procede de production de papier.

Info

Publication number
EP0394368A1
EP0394368A1 EP89903832A EP89903832A EP0394368A1 EP 0394368 A1 EP0394368 A1 EP 0394368A1 EP 89903832 A EP89903832 A EP 89903832A EP 89903832 A EP89903832 A EP 89903832A EP 0394368 A1 EP0394368 A1 EP 0394368A1
Authority
EP
European Patent Office
Prior art keywords
cationic
silica
sol
retention agent
process according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP89903832A
Other languages
German (de)
English (en)
Other versions
EP0394368B1 (fr
Inventor
Per Johan Svending
Hans Erik Johansson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nouryon Pulp and Performance Chemicals AB
Original Assignee
Eka Nobel AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eka Nobel AB filed Critical Eka Nobel AB
Priority to AT89903832T priority Critical patent/ATE89352T1/de
Publication of EP0394368A1 publication Critical patent/EP0394368A1/fr
Application granted granted Critical
Publication of EP0394368B1 publication Critical patent/EP0394368B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • 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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/63—Inorganic compounds
    • 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
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/06—Paper forming aids
    • D21H21/10—Retention agents or drainage improvers
    • 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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/03—Non-macromolecular organic compounds
    • D21H17/05—Non-macromolecular organic compounds containing elements other than carbon and hydrogen only
    • D21H17/10—Phosphorus-containing compounds
    • 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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20—Macromolecular organic compounds
    • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
    • D21H17/24—Polysaccharides
    • D21H17/31—Gums
    • D21H17/32—Guar or other polygalactomannan gum
    • 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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20—Macromolecular organic compounds
    • D21H17/33—Synthetic macromolecular compounds
    • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/37—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates
    • 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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/63—Inorganic compounds
    • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
    • D21H17/68—Water-insoluble compounds, e.g. fillers, pigments siliceous, e.g. clays

Definitions

  • a process for the production of paper The present invention relates to a process for the production of paper utilizing a combination of substances for improving retention and dewatering. More particularly the invention relates to the use of a combination of a cationic silica based sol and a cationic, organic, polymeric retention agent in papermaking.
  • anionic silica sols have been used in combination with cationic polymeric retention agents, such as for example cationic starch and cationic polyacrylamide.
  • cationic polymeric retention agents such as for example cationic starch and cationic polyacrylamide.
  • Such systems are disclosed for example in the European patent 41056 and the European patent tion 218674.
  • the effect of systems comprising an anionic silica sol and a cationic component is based on the interaction of the two differently charged substances and it is assumed that the sol particles with their strong anionic charges to some degree produce a cross-linking of the polymeric retention agent.
  • Cationic inorganic silica based colloids are per se known and their use in specific paper making processes is also known.
  • US patents 4309247 and 4366068 disclose the use of cationic inorganic silica colloids in the preparation of filter media based on cellulose fibers.
  • the preparation of the ink jet recording paper from a pulp slurry containing talcum, cationic starch and cationic colloidal silica is shown.
  • the present invention thus relates to a process for the production of paper by forming and dewatering a suspension of cellulose containing fibers and optionally fillers on a wire whereby said formation and dewatering takes place in the presence of a cationic silica based sol and a cationic polymeric retention agent selected from the groups cationic guar gum and cationic synthetic polymers.
  • Silica sols with positively charged particles are, as stated above, known per se and their preparation is disclosed for example in the US patents 3007878, 3620978 and 3713607.
  • the general methods for preparing cationic silica sols start from aqueous sols of silica which are reacted with a basic salt of a polyvalent metal to give the sol particles a positive surface charge and stabilizers such as boric acid, alkali metal bases, alkaline earth metal bases, ammonia etc are often used in the processes.
  • the polyvalent metal salt is usually an aluminum salt, due to availability and lower costs, although it is of course also possible to use basic salts of other polyvalent metals for preparing cationic silica based sols, such as chromium, zirconium and others. Any basic salt which is water soluble and gives the desired positively charged surface can be used and generally the cationic sols are prepared using chlorides, nitrates or acetates of the metal.
  • the particles of the cationic sols have a small average particle size, usually below 100 nm and the size is generally in the range of from 2 nm to 100 nm, more often in the range of 2 nm to 80 nm. Suitably the particle size is within the range of from 3 to 20, and preferably from 3.5 to 14 nm.
  • the cationic silica particles will have positively charged species of the polyvalent metal, preferably of aluminum, on their surfaces and the mole ratio of aluminum to surface silica can be within the range of from 1:8 to 4:1, suitably within the range of from 1:6 to 4:1 and preferably within the range of from 1:4 to 4:1. Most preferably the ratio is within the range of 1:2 to 4:1.
  • the mole ratio of aluminum to surface silica has here been calculated as in US patent 3,956,171, ie on basis of 8 silicon atoms per square nm of silica surface whereby the fraction of total silica occurring in the surface becomes 8 ⁇ 10 -4 xA, where A is the specific surface area of the sol particles in m 2 /g.
  • the cationic silica sols used according to the present invention can be prepared from any anionic silica sol by reaction with a basic salt of a polyvalent metal salt as above.
  • the cationic silica is added to the stock in the form of an aqueous sol.
  • the concentration in the cationic sol can be up to about 50 per cent by weight for sols made from commercial anionic silica sols and up to about 10 per cent by weight when made from polysilicic acid.
  • the stability of the last mentioned type of sols is limited and thus concentrations about or lower than 5 per cent are suitable. The stability is generally higher if more aluminum is present, within the above ratios. From a practical point of view it is anyhow suitable to dilute the sols to a concentration of from 0.05 to 5.0 per cent by weight of the cationic particles, preferably from 0.1 to 2 per cent by weight, before addition to the stock.
  • the cationic retention agents which are used in combination with the cationic silica sols are at papermaking conventional organic, polymeric retention agents, which have a cationic net charge at the pH at which they are used, and they are either cationic guar gum or synthetic cationic polymers.
  • suitable synthetic cationic polymers are cationic polyacrylamides, polyethyleneimines and polyamidoamines.
  • a mixture of two or more cationic retention agents as above can also be used, and any of these can also be used in combination with cationic starch.
  • Synthetic cationic retention agents are preferred, and particularly cationic polyacrylamide.
  • the amounts of cationic silica and of cationic retention agent which are used will of course depend on the particular stock, presence of fillers and other papermaking conditions. Usually amounts of from 0.005 to 2.0 per cent by weight of the cationic silica, as dry, based on dry fibers and optional fillers give good results and the amounts suitably used are from 0.005 to 1 per cent by weight. Amounts in the range of from 0.03 to 0.3 per cent are preferred.
  • the ratio of cationic retention agent to cationic silica will vary widely depending on for example the papermaking conditions, the particular cationic polymer and on other effects desired from this. Usually the weight ratio of cationic retention agent to cationic silica should be at least 0.01:1 and suitably at least 0.2:1.
  • the upper limit of the cationic retention agent with lower cationicity such as guar gum is not critical and can for such cationic polymers be very high, up to a ratio of 100:1, and higher, and the limit is usually set by economical reasons. Ratios of cationic retention agent to cationic silica within the range of 0.2:1 to 20:1 are suitable for most systems.
  • the two-component system of the present invention can be used in papermaking from different types of stocks of papermaking fibers, suitably from stocks containing at least 50 per cent by weight of cellulose containing fibers.
  • the components can for example be used as additives to stocks from fibers from chemical pulp, such as sulphate and sulphite pulp, thermo-mechanical pulp, refiner mechanical pulp or groundwood pulp, from as well hardwood as softwood.
  • the system of the invention can also advantageously be used for recycled fibers.
  • the stock can also contain mineral fillers of conventional types, such as eg kaolin, titanium dioxide, gypsum, chalk and talcum.
  • the two component system of the invention is particularly suitable for stocks made up from at least 25 per cent by weight of mechanical pulp and give a much improved effect in such systems compared with sols of anionic silica and a cationic retention agent.
  • the terms paper and papermaking, which are used herein, do of course not only include paper and its production, but also other cellulose fiber containing sheet or web form products, such as pulp sheet, board and cardboard and their production.
  • the cationic silica sol and the cationic polymeric retention agent can be added to the stock separately, simultaneously or premi-xed.
  • cationic silica and cationic retention agent can also be added in two or more increments. It is preferred that the two components are added separately. It seems that the order cf addition of the sol and the cationic retention agent has some influence on the obtained effect and that when the sols contain smaller particles a better effect is obtained if the cationic retention agent is added before the sol of cationic silica, while for sols of larger particles a better effect generally is obtained when the cationic silica is added first and the cationic retention agent is added subsequently.
  • the addition of cationic silica and cationic retention agent according to the invention considerably improves the retention of fines and fillers, when present, and also considerably improves the dewatering, in comparison with the use of solely the cationic retention agent.
  • the stock system was composed of 60% bleached birch sulphate pulp and 40% bleached pine sulphate pulp and 30% of China clay had been added to the system.
  • the chemical additions are calculated in kg per ton dry stock system (fibre + filler) and the amounts of sols and cationic polymers are given as dry substance. All chemical additions were made with a mixing speed of 800 rpm in a Britt Dynamic Drainage Jar with a blocked outlet for 45 seconds and the stock systems were then added to one Canadian Freeness Tester. In all tests the sol was added before the polymer. Different sols were used: a) Cationic aluminum modified silica sol with a mole ratio of aluminum to surface silica groups of 1.30:1 and a particle size of about 7.5 nm.
  • cationic polymers were used: A) Cationic polyacrylamide, PAM 1, of medium cationicity, sold by Allied Colloids under the name of Percol 292.
  • Cationic sol Anionic sol PolyacrylCSF kg/ton kg/ton amide kg/ton ml - - - 130 - - 0.5 210 - - 1.0 230 - - 2.0 250 - - 3.0 245
  • Sols a) and d) had been prepared according to the following: 19.49 g of a 50% solution of polyaluminum chloride [Al 2 (OH) 5 Cl.2H 2 O] x was diluted to 200 g. Into this solution 1000 g of a 1% polysilicic acid were pumped slowly during 45 minutes at room temperature. The polymeric silicic acid had been prepared according to the following: Water glass (Na 2 O.3SiO 2 ) was diluted with water to a SiO 2 content of 5 per cent by weight. The aqueous solution was ion exchanged using ion exchange resin Amberlite IR-120 to a pH of 2.3.
  • the specific surface area of the obtained acid polymeric silicic acid was measured by titration according to the method disclosed by Sears in Analytical Chemistry 28(1956)1981 and was found to be 1450m 2 /g.
  • This polymeric silicic acid which was later treated with polyaluminum chloride consisted of particles of a size of the order of about 1 nm, to some degree aggregated into chains and networks.
  • the obtained cationic silica sol had the follow ing analysis: 0.39% AI 2 O 3 and 0.84% SiO 2 and thus a mole ratio of A1 to surface silica of about 1:2.
  • Sol a) was made from a freshly prepared polysilicic acid and sol c) from a polysilicic acid which had been aged for 1 day.
  • Sols a) to d) were used together with a cationic polyacrylamide (PAM) sold under the designation Percol 292 by Allied Colloids in a stock made up from 60% birch sulphate pulp and 40% pine sulphate pulp. The stock further contained 30% calcium carbonate and 1 g/l of Na 2 SO 4 .10H 2 O. The pH of the stock was 8.5. The polyacrylamide was added to the stock before the cationic silica sol, except were otherwise indicated. The dewatering was evaluated as disclosed earlier using a Canadian Freeness Tester. The results are given in the following Table.
  • Sols a) and b) of Example 3 and also sols e) and f) were investigated in combination with cationic polyacrylamide for a stock made up from groundwood pulp.
  • Sol e) had been prepared according to the following: 27.84 g of a 50% solution of polyaluminum chloride [Al 2 (OH) 5 Cl.2H 2 O] x was diluted to 200 g. 1000 g of a 1% polysilicic acid, as in Example 3, was added to the polyaluminum chloride solution and the obtained product contained 0.56% Al and 0.83% SiO 2 and thus had a mole ratio of Al to surface silica of about 1:1.5.
  • Sol f had been prepared according to the following: 34.80 g of a 50% polyaluminum chloride, [Al 2 (OH) 5 Cl.5H 2 O] x , solution was diluted to 200 g and 1000 g of a 1% polysilicic acid was added to the solution.
  • the product contained 0.70% AI 2 O 3 and 0.83% SiO 2 and the mole ratio of Al to surface Si thus was about 1:1.2.
  • the groundwood pulp stock contained 2g/l of Na 2 SO 4 .10H 2 O and had a pH of 7.0.
  • the dewatering effect was investigated as described earlier. In most cases the cationic polyacrylamide was added to the stock before the addition of the sol, if not reversed dosage order (rdo) has been indicated.
  • the dosage of the cationic polyacrylamide was 1.0 kg/ton which had been found to be the optimum amount for this stock when it was used alone. In the tests it was noted that the water collected from the freeness tester was much more clear when combinations of sol and cationic polyacrylamide were used than when the polyacrylamide was used alone and this is an indication of very good fines retention.
  • PAM Sol amount CSF kg/ton kg/ton ml - - 120 1.0 - 195 - b); 1.0 120
  • a Britt Dynamic Drainage Jar was used to evaluate retention.
  • the stirrer speed was set to 800 rpm and the wire used was of 200 mesh.
  • the cationic silica sol used was sol a) according to Example 1 and this was added before the cationic retention agent.
  • the following cationic retention agents were used in the different runs:
  • the results of the tests are shown in the table below.
  • the filler and fines retention (FF ret.) is given in per cent at different dosages of the respective cationic polymers.
  • the dosage is calculated as dry polymer on dry pulp plus filler.
  • the cationic silica sol was used in an amount of l kg/ton of dry pulp plus filler. Comparisons were made with addition of solely the cationic polymer.

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  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Paper (AREA)

Abstract

Un procédé de production de papier consiste à former et à égoutter une suspension de cellulose contenant des fibres ainsi que des charges optionnelles sur un fil, en présence d'un sol à base de silice cationique et d'un agent de rétention polymère cationique. Ledit agent de rétention polymère cationique est une gomme de guar ou un polymère synthétique cationique tel qu'un polyacrylamide cationique. La combinaison de sol de silice cationique et de l'agent de rétention polymère cationique améliore la rétention de poussières et de charges, et facilite le drainage.
EP89903832A 1988-03-08 1989-02-14 Procede de production de papier Expired - Lifetime EP0394368B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT89903832T ATE89352T1 (de) 1988-03-08 1989-02-14 Verfahren zur herstellung von papier.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8800816 1988-03-08
SE8800816A SE462721B (sv) 1988-03-08 1988-03-08 Saett vid framstaellning av papper genom formning och avvattning av en suspension av cellulosainnehaallande fibrer

Publications (2)

Publication Number Publication Date
EP0394368A1 true EP0394368A1 (fr) 1990-10-31
EP0394368B1 EP0394368B1 (fr) 1993-05-12

Family

ID=20371616

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89903832A Expired - Lifetime EP0394368B1 (fr) 1988-03-08 1989-02-14 Procede de production de papier

Country Status (12)

Country Link
EP (1) EP0394368B1 (fr)
JP (1) JP2607161B2 (fr)
KR (1) KR920011032B1 (fr)
CN (1) CN1010599B (fr)
AU (1) AU3294989A (fr)
CA (1) CA1324705C (fr)
DK (1) DK215590A (fr)
ES (1) ES2010430A6 (fr)
FI (1) FI93882C (fr)
NZ (1) NZ228206A (fr)
SE (1) SE462721B (fr)
WO (1) WO1989008741A1 (fr)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE500387C2 (sv) * 1989-11-09 1994-06-13 Eka Nobel Ab Silikasoler, förfarande för framställning av silikasoler samt användning av solerna i pappersframställning
SE9103140L (sv) * 1991-10-28 1993-04-29 Eka Nobel Ab Hydrofoberat papper
DE4302293A1 (de) * 1993-01-28 1994-08-04 Degussa Füllstoff enthaltendes Papier
US7629392B2 (en) 2004-04-07 2009-12-08 Akzo Nobel N.V. Silica-based sols and their production and use
US7732495B2 (en) 2004-04-07 2010-06-08 Akzo Nobel N.V. Silica-based sols and their production and use
US7208429B2 (en) 2004-12-02 2007-04-24 The Procter + Gamble Company Fibrous structures comprising a nonoparticle additive
US7976679B2 (en) 2004-12-02 2011-07-12 The Procter & Gamble Company Fibrous structures comprising a low surface energy additive
US7459179B2 (en) 2004-12-02 2008-12-02 The Procter & Gamble Company Process for making a fibrous structure comprising an additive
CN105542275B (zh) * 2015-12-22 2017-11-14 温州德泰塑业有限公司 一种造纸用无机纤维柔性化的方法
FI128012B (en) * 2016-03-22 2019-07-31 Kemira Oyj System and method for making paper, cardboard or the like

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1148872A (fr) * 1979-04-06 1983-06-28 Eugene A. Ostreicher Filtre a base de silice cationique, colloidale, minerale
SE8403062L (sv) * 1984-06-07 1985-12-08 Eka Ab Forfarande vid papperstillverkning
JPS60260377A (ja) * 1984-06-08 1985-12-23 Mitsubishi Paper Mills Ltd インクジエツト記録用紙
SE451739B (sv) * 1985-04-03 1987-10-26 Eka Nobel Ab Papperstillverkningsforfarande och pappersprodukt varvid som avvattnings- och retentionsforbettrande kemikalie anvends katjonisk polyakrylamid och en speciell oorganisk kolloid
ES2007383A6 (es) * 1987-07-31 1989-06-16 Hispano Quimica Procedimiento para la obtencion de paneles de aislamiento termico y acustico
US4798653A (en) * 1988-03-08 1989-01-17 Procomp, Inc. Retention and drainage aid for papermaking

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8908741A1 *

Also Published As

Publication number Publication date
SE8800816L (sv) 1989-09-09
DK215590D0 (da) 1990-09-07
FI93882C (fi) 1995-06-12
ES2010430A6 (es) 1989-11-01
SE462721B (sv) 1990-08-20
CN1035859A (zh) 1989-09-27
CN1010599B (zh) 1990-11-28
WO1989008741A1 (fr) 1989-09-21
KR900700690A (ko) 1990-08-16
JP2607161B2 (ja) 1997-05-07
CA1324705C (fr) 1993-11-30
DK215590A (da) 1990-09-07
KR920011032B1 (ko) 1992-12-26
FI93882B (fi) 1995-02-28
AU3294989A (en) 1989-10-05
JPH03503299A (ja) 1991-07-25
SE8800816D0 (sv) 1988-03-08
FI904384A0 (fi) 1990-09-05
EP0394368B1 (fr) 1993-05-12
NZ228206A (en) 1990-04-26

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