WO2014001222A1

WO2014001222A1 - Process for producing filled paper and card using coacervates

Info

Publication number: WO2014001222A1
Application number: PCT/EP2013/063050
Authority: WO
Inventors: Jovica Zorjanovic; Ulrich Sohling; Friedrich Ruf; Moritz KLICKERMANN; Lars DÄHNE
Original assignee: Clariant Produkte (Deutschland) Gmbh
Priority date: 2012-06-25
Filing date: 2013-06-21
Publication date: 2014-01-03
Also published as: DE102012012561A1

Abstract

The invention relates to a process for producing filled paper or card, wherein an aqueous fibre suspension is produced which contains cellulose fibres and at least one filler, and the fibre suspension is flocculated using a flocculation system which comprises as components at least one inorganic microcomponent and one coacervate which is formed from at least one cationic polymer and an anionic polymer, and the flocculated fibre suspension is processed to form a filled paper or a filled card.

Description

Process for producing filled paper and cardboard under

Use of coacervates

The invention relates to a process for the production of filled paper or cardboard, wherein an aqueous

Fiber suspension is produced, which contains cellulose fibers and at least one filler, and the fiber suspension is flocculated with a flocculation system.

In industrial papermaking, the

Sheet formation on paper machines taking place. This is a

Purified and bled pulp consisting of about 99% water and containing about 1% pulp fibers

Headbox is formed into a thin, as uniform as possible beam. This is given in Langsiebpapiermaschinen on a rotating endless sieve. Within a few seconds most of the water runs off and it forms a paper structure. Fourdrinier machines can work up to a speed of about 1200 m / min. At higher speeds, the paper formation is through

Air turbulence disturbed. Modern paper machines,

so-called gap formers, produce at speeds of up to 2000 m / min at working widths of more than 10 m.

Here, the pulp is injected directly into a gap between two rotating screens. In addition to the higher

Running speed Gap-formers also offer the advantage of a much more uniform drainage and consequently a reduced two-sidedness of the paper. At the end of the screen, the soft paper web is transferred to a felt and enters the press section, where the paper web is dewatered by means of rollers pressed against each other between felts. In the dryer section finally finds the final Drainage takes place, the web passes through a number of steam-heated drying cylinder. Then the paper web is smoothed and rolled up. For highly smooth and sharply satined papers, another final smoothing step can be performed in the calender before final rolling up.

In addition to pulp fibers contains the pulp or the

Fiber suspension even more ingredients that the

Properties of the paper or its production method

influence. So the fiber suspension usually still contains

Fillers in a proportion of up to 30 wt .-%, based on the fiber content. Suitable fillers are, for example, kaolin, talc, titanium dioxide, starch and calcium carbonate. Kaolin remains chemically inert over a wide pH range and therefore can be used in both acidic and alkaline production processes. Kaolin has been the most widely used pigment in the past. However, it has been increasingly replaced by calcium carbonate in recent years. Calcium carbonate has a higher whiteness compared to kaolin, which is particularly advantageous in the production of recycled paper. A distinction is made between ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC). Ground calcium carbonate is made from CaCO3-containing minerals such as limestone, chalk or marble. First, in a sifting process, sludge and

Impurities such as colored silicates, graphite and pyrite removed. The raw material is then further crushed and ground until the desired grain size is reached. GCC has a large brightness spectrum. If a high degree of brightness is required, mostly marble is used as starting material. GCC has replaced kaolin as the main filler pigment.

Precipitated calcium carbonate is a synthetic one

Industrial minerals made of quicklime or limestone will be produced. As a synthetic product, PCC can be modified in its properties to affect the properties of the paper. So by the at the

Production of PCC set reaction parameters the

Grain, the grain shape, the specific surface and the

Surface chemistry and the particle size distribution can be influenced. With PCC, therefore, the properties of the paper can be controlled, such as its brightness or that

Translucence or the thickness of the paper layer. However, PCC can not be used indefinitely as a filler because it reduces fiber strength.

Fillers soften and soften the paper by filling in the gaps between the fibers, giving it a smooth surface. The mass fraction of

Fillers is expressed in the ash number.

In addition to fillers, dyes and optical brighteners may also be present in the fiber suspension. Here mainly synthetic dyes are used. To make the paper writable, sizing agents are added. This makes the paper less absorbent and less absorbent

hygroscopic. The sizing agents are chemically modified

Tree resins in combination with acid salts, such as potassium alum or aluminum sulphate. Polymers based on acrylates or polyurethanes are also used. In the production of the paper web is important that the

Water of the fiber suspension flows quickly, without causing substantial amounts of fibers or fillers are discharged with the water and thus lost. Furthermore, a stable paper structure should be formed. For process optimization as well as specific

Paper properties will be achieved during the course of Production chain additives added to the fiber suspension. An important role is played by additives, which

Improvement of retention and drainage in the

Contribute to papermaking. In the retention is the

Objective, as much as possible of the used

To retain filler in the pulp. Drainage is about removing the water from the suspension during the

Sheet formation in the paper machine to drain as quickly as possible, so that a dry paper sheet can be formed quickly. Both objectives, high retention and rapid drainage, are closely related, and the improvement of one parameter should not be at the expense of the other.

The sheet formation is a very fast running

Filtration process. Assuming a pure fiber suspension in which no special interactions between the fibers occur, formed during the filtration by the turbulent flow, a disordered nonwoven structure. The nonwoven here has disordered fluctuations, for example, in the paper thickness or basis weight. Contains the

Fiber suspension fillers, these are not retained during filtration of the sieve and therefore washed out with the outflowing water for the most part. The sheet would then contain no or only small amounts of filler in such a process management. The fiber suspension is therefore added with chemical additives which can interact with both the fibers and the filler particles. These interactions lead to the formation of larger aggregates of fibers and even before filtration

Filler particles. The fiber suspension flocculates

Formation of larger flakes, in which fibers and

Filler particles are bound. Due to the chemical additive, usually a charged polymer, the flakes themselves contain one Charge. However, these flakes have a low mechanical strength, so that they can be easily cut by the action of shearing forces.

In recent decades, many retention and retention

Drainage systems developed. The aim is to optimize retention and drainage independently of each other. One differentiates between two-component and multi-component retention and drainage systems.

In dual retention and drainage systems, the

Fiber suspension initially a high molecular weight cationic

Polymer added to precipitate the fibers in the form of flocs from the fiber suspension. After a possibly yourself

subsequent step, in which the flocculated suspension is subjected, for example by stirring shear forces to produce microflakes, a bentonite is added, which causes a compound of the flakes and after separating the water to form a stable paper structure. It is desired that the bentonite is present in the strongest possible delaminated form, so that a high number of

Particles for connecting the flakes is available. The mixture is then placed on a sieve so that the water can run off and form a stable paper layer. Dual retention and drainage systems are often also referred to as microparticle systems and may, for example, also a combination of one or more cationic

Polymers and anionically charged microparticles, such as

For example, anionically charged organic components, silica particles or swellable clay materials. A commercial, available on the market dual retention and drainage system is for example the Hydrocol ^® system.

A dual retention and drainage system is described for example in EP 0 235 893 B2. This is an aqueous Cellulose suspension initially with a substantially

linear synthetic cationic polymer with a

Molecular weight of over 500,000 g / mol flocculated. The

cationic polymer is used in an amount of at least 0.03 wt .-% based on the dry weight of the suspension

added. The flakes formed by adding the polymer are sheared to form microflakes

broken up, which further dismantling by shearing

resist and carry sufficient cationic charge so that they can interact with bentonite added to the suspension after shearing. The re-flocculated suspension then becomes a paper web

processed. As the cationic polymer, for example, polyethyleneimine, polyaminoepichlorohydrin products, polymers of diallyldimethylammonium chloride and polymers of

Acrylic monomers comprising a cationic acrylic monomer. The bentonite is preferably added in delaminated form. It is preferably used as a hydrated suspension obtained by dispersing powdered bentonite in water. The bentonite is in one

Amount of 0.03 to 0.5 wt .-%, based on the dry weight of the suspension added. The cellulosic fiber suspension may also contain a filler, such as

Calcium carbonate. Multi-component systems, in addition to a high molecular weight cationic polymer and an anionic microparticle, such as a layered silicate or silica particles, still contain a high

crosslinked organic microparticle. With such a three-component system, not only the filler retention can be significantly improved, but also the retention

be influenced independently of the drainage. This means that the filler retention can be varied with the third and possibly also a fourth component without doing so the drainage is negatively affected. A well-known multi-component system on the market is under the brand

Telioform ^® offered.

In WO 02/33171 A1 a process for the production of paper or paperboard is described, wherein a

Pulp fiber suspension is precipitated with a flocculation system, which comprises in addition to a cationic polymer and a silicate-containing material as a further component of organic microparticles which have a particle diameter of less than 750 nm in the non-swollen state. The microparticles consist of a highly crosslinked polymer and preferably carry an anionic charge. The

For example, microparticles can be made by

Microemulsion methods are prepared by a

aqueous solution of a cationic or anionic monomer and a crosslinking agent in the presence of a saturated hydrocarbon and a surfactant is reacted to produce particles having a size of less than 0.75 microns. Polymerization to produce microparticles is initiated by the addition of an initiator or by irradiation of the emulsion with ultraviolet light. To control the chain length of the emulsion

Chain transfer agent may be added. Crosslinked organic polymeric microparticles have been found to have high effectiveness as retention and drainage aids when their particle size is less than about 750 nm, preferably less than about 300 nm, and that non-crosslinked

organic water-insoluble polymer microparticles show high efficiency when their size is less than 60 nm. The improvement of the filler retention as well as the

Drainage speed is a constant challenge in papermaking. The tools used should be easy to display and easily available, in small Quantities already show good efficacy and allow independent influence of parameters such as drainage and filler retention.

The invention was therefore based on the object, a method for producing filled paper or cardboard

which can be carried out economically and only small amounts of easily accessible

Supplies needed.

This object is achieved by a method having the features of patent claim 1. Advantageous embodiments of the method are the subject of the dependent claims.

In the method according to the invention a coacervate is used as auxiliary component, which is formed from at least one cationic polymer and an anionic polymer. The cationic polymer and the anionic polymer are in the

Coacervate is not bound by covalent bonds but is separately present as individual components. In the coacervate, cationic and anionic polymers are held together by electrostatic forces and possibly steric effects in a complex to form an organic microparticle that has multiple constituents that are not bound together by covalent bonds. The charge of the coacervate may be due to the charge of its constituents, cationic polymer and anionic polymer, as well as the ratio in which the polymers in the

Coacervate are included. The coacervates form stable microparticles, so that an emulsion or

Dispersion of the coacervate in water over several days can be stable. The use of coacervates causes a

significant improvement of both the drainage properties and the filler retention, so that the

Paper production process economically efficient can be carried out. By variation of the

Coacervate composition, the parameters of drainage and filler retention can be influenced, so that a further improvement of the papermaking process is possible.

In particular, it has been found that coacervates are excellent flocculants for fillers, in particular

Calcium carbonate, and thus in papermaking can bring significant improvements in the filler retention, without negatively affecting the drainage properties. According to the invention, therefore, there is provided a process for producing filled paper or paperboard, wherein an aqueous fiber suspension is prepared which contains fibers and at least one filler, and the fiber suspension is flocculated with a flocculation system which

Component comprises at least one inorganic microcomponent, preferably an anionic inorganic microcomponent, and a coacervate, which consists of at least one

cationic polymer and an anionic polymer is formed, and the flocculated fiber suspension is processed into a filled paper or paperboard.

The process according to the invention for the production of filled paper and paperboard is carried out in a manner analogous to the customary processes of this type, but in the case of flocculation the fiber suspension, in addition to the inorganic microcomponent,

For example, a silicate material, a coacervate is added as an additional aid.

The process according to the invention is based on an aqueous suspension which is preferably 0.1 to 10% by weight, more preferably 0.4 to 3% by weight and, according to a further embodiment, 0.6 to 1.5% by weight. Contains fibers. The fibers used are preferably a cellulose fiber material. Such a cellulose fiber material can in the usual way by chemical pulping of wood or

A shrub to be won. The pulp fibers

consist predominantly of cellulose and can still small

Contain proportions of polyoses or lignin. As a fiber material but can, for example, a recycled material

Waste paper can be used. Likewise, mixtures of such materials may be used. Furthermore, the suspension contains, based on the content of

Fibers, preferably up to 40 wt .-%, according to a

Embodiment 5 to 35 wt .-% fillers. Fillers which can be used in papermaking are customary fillers, with inorganic fillers being preferred.

Suitable fillers are, for example, titanium dioxide, natural or precipitated chalk (calcium carbonate), talcum, kaolin, satin white, calcium sulfate, barium sulfate, clays or

Alumina. The fiber suspension preferably passes through at least one cleaning, mixing and / or pumping stage. The shearing of the fiber suspension can, for example, in a

Pulper, classifier or done in a refiner. Preferably, the coacervate is added after the last shear stage.

Subsequently, the flocculated fiber suspension to

Leaf formation poured out on a sieve. The inorganic microcomponent of the flocculation system may co-exist with the coacervate after the last shear stage

be added. However, it is also possible first to add the inorganic microcomponent, then preferably to shear the pulp again and only then to add the coacervate. Preferably, however, proceeding in such a way that inorganic microcomponent and coacervate are added after the last shear stage. The addition of

inorganic microcomponent and coacervate can simultaneously or one after the other. According to a particularly preferred embodiment, first the inorganic microcomponent is added and then the coacervate.

For example, phyllosilicates, in particular bentonite, are used as the inorganic microcomponent of the flocculation system.

colloidal silica, silicates and / or calcium carbonate into consideration. The particle size of the inorganic microcomponent is preferably selected to be very small and is preferably less than 200 μm, according to a further embodiment less than 150 μm and is according to another

Embodiment preferably in the range of 10 nm to 100 microns. The size of the microparticles refers to the average size D ₅ o of the microparticles and is preferably by optical

Methods such as light scattering determines and gives the

number-average value. Preferably, at least 50% of the particles have a size in the range of ± 30% of the mean. The inorganic microcomponent preferably has an anionic charge so that it can be mixed with fiber flakes in

Interaction can occur, which preferably have a cationic excess charge.

Silicates are understood to mean products based on silicates or silicic acid, for example silica microgel, silica sol, polysilicates, aluminum silicates,

Borosilicates, polyborosilicates, clays or zeolites.

Calcium carbonate can be used, for example, in the form of chalk, ground calcium carbonate or precipitated calcium carbonate as the inorganic microcomponent of the flocculation system. Layered silicates, in particular bentonite, are generally layered silicates, in particular aluminosilicates

understood, which are swellable in water. Particularly preferred is montmorillonite or bentonites with a high

Montmorillonite content, for example with a Montmorillonite content of more than 50 wt .-%. It is also possible to use bentonite-like clay minerals or layer silicates, such as nontronite, hectorite, saponite, sauconite, beidellite, alevardite, illite, halloysite, attapulgite and sepiolite. These layer silicates are preferably for use

activated, that is in a water-swellable form

transferred by adding the layer silicates with a

Alkali metal salt treated, for example, soda. Preferably, phyllosilicates, in particular bentonite, as

inorganic microcomponent used.

The inorganic microcomponent is preferably added in the form of a suspension to the fiber suspension. The suspension preferably has a solids content in the range from 0.5 to 10% by weight, preferably from 1 to 5% by weight. In the

Use of layered silicates as inorganic

Microcomponent, the layered silicate is preferably used in as completely delaminated form. Of the

Platelet diameter of the water dispersed

Layered silicate is preferably in the range of 1 to 2 microns, the thickness of the platelets is preferably 0.1 to 10 nm, according to one embodiment in the range of 1 to 5 nm. The bentonite preferably has a specific surface area in the range of 60 to 800 m ² / g on. The determination of

specific surface area can be determined according to DIN 66131 using nitrogen porosimetry.

As the colloidal silicic acid or as silicates, products from the group of silicon-based particles, silica nitrogels, silica sols, aluminum silicates, borosilicates,

Polyborosilicates or zeolites are used. These

Materials typically have a specific surface area in the range of 50 to 1000 m ² / g and an average particle size distribution of 1 to 250 nm, for example in the range of 40 to 100 nm. As the inorganic microcomponent are preferably silicate materials, more preferably layer silicates and

particularly preferably used bentonites.

The inorganic microcomponent of the flocculation system is preferably added to the aqueous fiber suspension in an amount of 0.01 to 1.0% by weight, more preferably in an amount of 0.1 to 0.5% by weight, based on the solid content of

Fiber suspension, added.

The flocculated fiber suspension is then processed in the usual way to a paper or cardboard. This can

for example, preferably without further action of

Shearing forces, to be poured on a sieve under sheet formation. The paper sheets are then dried.

Besides the flocculation system, one can use the fiber suspension commonly used in papermaking

Add process chemicals in conventional amounts, such as

Example fixatives, dry and wet strength agents,

Engine sizing agents, biocides and / or dyes.

The coacervate used in the manufacture of filled paper or board according to the invention may be neutral, but it is preferred that the coacervate has an excess charge. The excess charge can be generated by one of the two polymers used for the preparation having a higher charge than the oppositely charged one

Polymer. This can be achieved, for example, by one of the polymers having a higher molecular weight for the same percentage of charged monomer units or by one of the two polymers having a higher percentage of charged monomers at the same molecular weight. Mixed forms of these embodiments are also possible. The percentages refer to each Entity of the monomer units contained in a polymer, for example acrylate or acrylamide units, which are derived from the corresponding monomers, for example acrylates or acrylamides. The charge of the coacervate is determined by the polymer used in excess in relation to its charge. According to the inventors' model, the charge-in-excess polymer forms the core of the coacervate, while the excessively charged groups present on the outside of the coacervate. Preferably, the coacervate has an anionic excess charge.

According to one embodiment, anionic and cationic polymers in a charge ratio in the range of 0.1 to 0.95, according to another embodiment in the range of 0.2 to 0.7 and according to yet another embodiment in

Range from 0.2 to 0.5 in the coacervate. The

Charge ratio is determined by the ratio of the charged groups in the one polymer to the charged one

Groups in the other, oppositely charged polymer. If one or both of the charged polymers have a molecular weight distribution, this refers to

Ratio each to the average number of charged

Groups per the respective polymer, here on the

Number average is referenced. As already stated, the coacervate may have a positive or a negative excess charge. Accordingly, the anionic or cationic polymer may be contained in the coacervate in excess. At the above ratio, both the anionic and the cationic polymer may be present in excess. Preferably, the anionic polymer is present in excess. The process is preferably carried out by first preparing an aqueous dispersion of the coacervate so that the coacervate is already formed and in the form of small particles, and the aqueous dispersion of the coacervate is subsequently added to the aqueous fiber suspension. The fiber suspension can already be present in a flocculated state. The flocculation of the fibers can, for example, by adding the inorganic

Microcomponent have been effected. Preferably, the coacervate is in the form of an aqueous

Dispersion added. For the preparation of the dispersion of

Coacervate anionic and cationic polymer are added to an aqueous solvent, the addition can be done both sequentially and simultaneously. After the addition of anionic and cationic polymer, which preferably takes place with stirring, a turbidity forms. Particularly advantageous results in terms of drainage and retention are obtained when the aqueous dispersion of the coacervate remains stable for a long time and

For example, no flocculation occurs during storage. The storage is preferably carried out at room temperature. The

Dispersion of the coacervate is preferably adjusted so that the turbidity of the dispersion remains stable for at least six days and no flocculation occurs. If the coacervate flocculates prematurely, the turbidity stability can be adjusted, for example, by the ratio of anionic and cationic polymer or by the concentration of coacervate in the aqueous dispersion. The flocculation of the sample can be visually detected as the flocs fall and the supernatant solution becomes clear. Possibly. can the stability of the

Dispersion can also be measured by measuring the turbidity by absorption at a wavelength of 500 nm. According to a preferred embodiment, the coacervate dispersion has a content of coacervate in the range of 0.1 to 15 wt .-%, preferably 0.2 to 2 wt .-%, according to a

Another embodiment in the range of 0.25 to 0.3 wt .-%. The content of coacervate can be calculated from the amount of anionic and cationic polymer added to the aqueous solvent. After the addition of the anionic polymer and the cationic polymer to the aqueous solvent, the dispersion is preferably agitated for a period of at least 10 minutes, preferably at least 30 minutes, more preferably at least one hour, so that the coacervates can form. The

Production of the coacervates preferably takes place

Room temperature. According to one embodiment, the

Production of the coacervate at a temperature of more than 10 ° C, according to another embodiment of more than 15 ° C. According to one embodiment, the production of the

Coacervates at a temperature of less than 30 ° C.

To facilitate the formation of the coacervate or the

To stabilize dispersion of the coacervate is according to a

Embodiment provided that the dispersion of the coacervate contains an electrolyte. A suitable electrolyte are salts of monovalent cations, more preferably of

Alkali metal cations. A particularly preferred electrolyte is sodium chloride. The concentration of the electrolyte in the

Dispersion of the coacervate is preferably selected in the range of 0.1 to 2 wt .-%, according to another embodiment in the range of 0.2 to 1 wt .-%. In the production of

Dispersion of the coacervate is preferred in the manner

proceeded that first the electrolyte in the aqueous

Solvent is dissolved and then the cationic and the anionic polymer is added. According to the inventors, the coacervate comprises a core composed of the one charged polymer and a shell disposed around the core and which is formed by the oppositely charged polymer. In order to facilitate formation of the coacervate, it is provided according to one embodiment that at least one of the at least one cationic and at least one anionic polymer contained in the coacervate has a linear structure. Preferably, at least the one polymer has an uncrosslinked, linear structure, which the

Generates excess charge and thus determines the charge of the coacervate. That in terms of cargo in deficit

The polymer contained may also have a crosslinked structure

exhibit. However, it is preferred that both charged polymers have a linear structure. A linear structure is understood as meaning a structure in which the polymer has as a backbone a linear carbon chain which, however, may optionally also contain heteroatoms, such as oxygen or nitrogen atoms. In order to be able to provide stable coacervates it is preferred that the cationic polymer or the anionic polymer has a certain chain length or a certain molecular weight. According to one embodiment, it is provided that the coacervate-forming at least one cationic polymer and the at least one anionic polymer each have a molecular weight of more than 50,000 g / mol. According to another

Embodiment is provided that the at least one cationic polymer and / or the at least anionic polymer has a molecular weight of more than 100,000 g / mol, according to another embodiment, a molecular weight of at least 200,000 g / mol. According to another

Embodiment is provided that the cationic polymer and / or the at least one anionic polymer Molecular weight of less than 3,000,000 g / mol. The molecular weight of anionic polymer and cationic polymer may be the same or different. According to one embodiment, it is provided that the molecular weight of the one polymer is significantly greater than the molecular weight of the oppositely charged polymer. In one embodiment, this includes a polymer

Molecular weight of at least 500,000 g / mol, according to another embodiment, a molecular weight of at least 1,000,000 g / mol, while the molecular weight of the

opposite charged polymer is preferably selected in the range of 100,000 to 500,000 g / mol.

The cationic polymer according to one embodiment comprises uncharged monomer units as well as cationic ones

Monomer units. Monomer units are understood to mean in each case repeating units contained in the polymer, which are derived from the monomers used to prepare the polymer. Uncharged monomer units do not include a group carrying a charge. Cationic or anionic

Monomer units accordingly comprise a group which carries a cationic or an anionic charge.

Cationic monomer units preferably comprise one

nitrogen-containing group, which either by way of

Protonation or by alkylation receives a permanent positive charge.

The cationic polymer according to one embodiment comprises cationic monomer units, wherein the proportion of the

cationic monomer units in the entirety of the cationic polymer-forming monomer units according to one embodiment at least 2 mol%, according to another

Embodiment at least 5 mol% and according to yet another embodiment, at least 10 mol%. According to one In another embodiment, the proportion of the cationic monomer units based on the total number of

Monomer units of the cationic polymer at least 20 mol%, according to another embodiment at least 30 mol%. The cationic polymer can only be cationic

Be constructed monomer units. According to another

Embodiment, the proportion of cationic

Monomer units of the entirety of the cationic polymer-forming monomer units less than 80 mol%, according to another embodiment, less than 60 mol%. According to a further embodiment, the proportion of the

cationic polymer contained cationic monomer units less than 50 mol%, according to yet another

Embodiment less than 40 mol%. The cationic groups of the cationic polymer are preferably formed by nitrogen-containing groups which preferably carry a permanent positive charge, the

is generated for example by alkylation of the nitrogen atom. Suitable cationic monomers from which the cationic monomer units are derived are compounds having an unsaturated carbon-carbon double bond and a positively charged group. The positively charged group may already be present in the monomer or only after the polymerization of the carbon-carbon

Double bond produced by a corresponding modification in the polymer or introduced into this. Such

Modification would be, for example, the alkylation or

Protonation of an amino group. Suitable monomers which by protonation or

Alkylkierung can get a positive charge are for example, N, -Dialkylaminoalkyl (meth) acrylamides and N, -Dialkylaminoalkyl (meth) acrylates. The alkyl groups on

Nitrogen atom preferably comprise 1 to 4

Carbon atoms. Particularly preferred are the methyl and the ethyl group. Exemplary monomers are 2-

(Dimethylamino) ethyl acrylate, 2- (diethylamino) propyl acrylate, 2-

(Dimethylamino) ethylmethacrylamide, 2-

(Diethylamino) ethylacrylamide, 2-

(Diethylamino) propylmethacrylamide. The cationic polymer preferably contains monomer units which carry a permanent positive charge by alkylating the nitrogen atom. Suitable monomers are, for example, (meth) acrylamidoalkyltrialkylammonium halides and (meth) acryloxyalkyltrialkylammonium halides. The

Alkyl groups on the nitrogen atom may be the same or different and preferably comprise 1 to 4 carbon atoms.

The alkyl group is particularly preferably selected from the methyl group and the ethyl group. The alkyl group of

Alkylamino group preferably comprises 1 to 12 carbon atoms, preferably 1 to 4 carbon atoms, and is more preferably a methyl, ethyl or propyl group. Exemplary suitable monomers are 3-

Acrylamidopropyltrimethylammonium chloride as well

Acryloxyethyltrimethylammonium chloride. Generally, as monomers having a cationic group, compounds of the formula I are suitable.

Where:

R: H, CH ₃

R ^{2 is} H, C 1 -C ₄ -alkyl

R ³ , R ⁴ : H, C 1 -C ₂ -alkyl, aryl or hydroxyethyl

R ^5: H, CH ₃

X: 0, NR ⁵

A: Alkylene having 1 to 12 carbon atoms, wherein at least two groups of R ² , R ³ , R ^{4 are} not H and in the case that R ² , R ³ and R ^{4 are} alkyl groups, they may be the same or different.

R ¹ and R ⁵ may be the same or different. Next are as cationic monomers

Diallyldialkylammoniumhalogenide suitable, the

Alkyl groups may be the same or different and may comprise 1 to 4 carbon atoms. Particularly preferred is poly-DADMAC:

The cationic groups are preferably in the form of their

Halides before. The halides include fluorides, chlorides, bromides and iodides, with chlorides being particularly preferred.

As uncharged monomers may be present in the cationic polymer

For example, alkyl (meth) acrylates and (meth) acrylamides or other uncharged ethylene compounds may be included. The cationic polymer is particularly preferably selected from the group of polyacrylamides, polyethyleneimines,

Polyvinylamines, polyethylene glycols, poly-DADMAC, as well as native polymers, such as cationic starch or chitosan.

More preferably, the cationic polymer is selected from the group of polyacrylamides, polyethyleneimines,

Polyvinylamines, poly-DADMAC.

The polymers may be given a positive charge by alkylation.

Suitable cationic polymers are, for example

Polyamine / Epichlorhydrinpolymere and homo- or copolymers of acrylamide and, for example, diallyldimethylammonium chloride.

The anionic polymer contained in the coacervate comprises

anionic monomer units, wherein the proportion of the anionic monomer units in the entirety of the anionic polymer-forming monomer units according to one embodiment

at least 2 mol%, according to a further embodiment, at least 5 mol% and according to yet another

Embodiment is at least 10 mol%. According to another embodiment, the proportion of the anionic monomer units based on the total number of

Monomer units of the anionic polymer at least 20 mol%, according to another embodiment, at least 30 mol%. According to a further embodiment, the proportion of

anionic monomer units in the entirety of the

anionic polymer-forming monomer units less than 50 mol%, according to another embodiment, less than 40

The anionic polymer can only be anionic

Be constructed monomer units. According to another Embodiment, the proportion of anionic

Monomer units of the total of the anionic polymer-forming monomer units less than 80 mol%, according to another embodiment, less than 60 mol%. According to a further embodiment, the proportion of the anionic monomer units contained in the anionic polymer is less than 50 mol%, according to yet another embodiment less than 40 mol%.

Come as anionic monomers or monomer units

Compounds with an unsaturated carbon-carbon double bond and a negatively charged group in

Consideration. Exemplary anionic monomers are

(Meth) acrylic acid, 2-acrylamido-2-methylpropanesulfonate,

Sulfoethyl (meth) acrylate, vinylsulfonic acid, styrenesulfonic acid and maleic acid. The enumeration of the anionic monomers should not be understood as exhaustive but merely as an example.

The anionic groups of the anionic monomer units of the anionic polymer can be used in the polymerization of the monomers for the preparation of the anionic polymer in the

Polymer are introduced. However, it is also possible for the anionic groups of the anionic monomer units to be introduced into the anionic polymer only after the polymerization, for example by saponification of an ester group present in the polymer.

The anionic monomers can be copolymerized with neutral monomers to the anionic polymer. Exemplary neutral monomers are (meth) acrylamide, N-alkylacrylamides, such as N-methylacrylamide, alkyl (meth) acrylates, such as

Methyl (meth) acrylate. According to a preferred embodiment, the anionic polymer is selected from the group of polyacrylates,

Polyacrylamides, as well as copolymers of acrylates and

Acrylamides, anionic starches, cellulose derivatives such as caboxymethyl, -ethyl, -propylcelullose, cellulose ethers, alginates, carrageenans, these polymers each

have anionic groups.

According to a preferred embodiment, anionic and cationic polymers are selected from the group of

Poly (meth) acrylates and poly (meth) acrylamides, wherein also mixed polymers are suitable, these polymers

anionic or cationic monomer units.

The process according to the invention produces filled papers or paperboards. As fillers, the fillers known from the production of paper or paperboard can be used per se. According to a preferred embodiment, the filler is selected from calcium carbonate, which may be in precipitated or ground form, clays,

Titanium dioxide, talc, kaolin, magnesium carbonate, barium sulfate, zinc sulfide and calcium silicates.

The filler preferably has a particle size (D ₅₀ ) of less than 10 microns, preferably less than 5 μηι and according to another embodiment, a particle size of less than 1 μηι on. According to one embodiment, the mean is

Particle size D _{50 of} the filler at least 10 nm, according to another embodiment, at least 100 nm

Embodiment, the filler particles have a size (D ₁₀₀ ) of less than 1 mm, according to another embodiment of less than 500 μηι and according to another embodiment of less than 300 μηι on. The values refer to

number-average values. The proportion of the filler is according to one embodiment less than 50 wt .-%, according to another embodiment, less than 40 wt .-% and according to another

Embodiment less than 30 wt. %, and according to one embodiment is more than 1% by weight, according to a further embodiment more than 10% by weight, according to yet another embodiment more than 20% by weight. The

Percentages refer to the dry weight of the

Fiber suspension. Particularly preferred is calcium carbonate as a filler

used. As calcium carbonate can be natural

Calcium carbonate (ground calcium carbonate, GCC) or precipitated calcium carbonate (PCC)

be used. GCC is produced by milling and visual processes using grinding aids. The

specific surface area is preferably in the range of 6 to 2 m ² / g. PCC is activated by the introduction of carbon dioxide

Calcium hydroxide solution prepared. The values are based on the particle number. The specific surface area can be greatly influenced by the choice of precipitation conditions. It is preferably in the range of 6 to 13 m ² / g.

According to a particularly preferred embodiment, in addition to the inorganic microcomponent and the coacervate, the flocculation system comprises at least one further flocculation component which is selected from at least one further anionic polymer and at least one further cationic polymer.

As such, neutral polymers can also be used as others

Flocculation component can be used. However, charged polymers are preferred. An exemplary nonionic or

neutral polymer, as another flocculation component

can be used is polyacrylamide, which

preferably a molecular weight between 500,000 and 7,000,000 g / mol. Polyacrylamides can be passed through

Homopolymerization of acrylamide produce.

The polymers of the further flocculation component are added individually, that is, either only anionic polymer is added or only cationic polymer. The as more

Flocculation component used polymers are therefore not in the form of a coacervate. According to one embodiment, the polymer used as an additional flocculation component has an overall charge whose sign is opposite to the total charge of the coacervate. The amount is the

Total charges of as an additional precipitation component

used polymer and the coacervate in general

differently. Preferably, cationic polymers are added as an additional precipitation component. The addition of the polymers used as additional precipitation component causes a flocculation of the fiber suspension, which can form relatively large and loose flakes. The amount of the anionic or cationic polymer is chosen so that the flakes receive an anionic or cationic total charge.

In essence, as another precipitating component

cationic polymers are used, as they were already mentioned above as part of the coacervate.

Anionic polymers can also be used as further precipitation component, in which case it is likewise possible to use anionic polymers, as already mentioned above as part of the coacervate.

The polymers used as further flocculation component are preferably substantially linear and, according to one embodiment, have a molecular weight of more than 500,000 g / mol, preferably has a molecular weight of more than 1 x 10 ⁶ g / mol and according to another embodiment has a molecular weight of more than 5 x 10 ⁶ g / mol. According to another

Embodiment, the molecular weight of the polymer used as a further flocculation component is less than 5 × 10 ⁸ g / mol.

Polymers usually show no uniform molecular weight but have a molecular weight distribution. The molecular weight data refers to the number average molecular weight of the polymer. The molecular weight can be, for example, with the help of

Determine size exclusion chromatography versus standards.

The amount of the polymer used as a further flocculation component, preferably cationic polymer, is based on the dry mass of the fiber suspension, according to a

preferred embodiment selected greater than 0.03 wt .-%. According to a preferred embodiment, the amount of added as a further flocculation polymer is less than 0.5 wt .-%, according to another embodiment, less than 0.2 wt .-%. According to a preferred embodiment, the amount of polymer added as a further component of the flocculation system is selected in the range of 0.06 to 0.15, in another embodiment in the range of 0.07 to 0.12 wt .-%.

Cationic polymers suitable as additional flocculation component are, for example, polyethyleneimines, which can also be further crosslinked by grafting polyethylene glycol bis-chlorohydrin ethers onto the free secondary amino groups. Also suitable are polyvinylamines. Preferred cationic polymers are, for example, dialkylaminoalkyl (meth) acrylates and

Dialkylaminoalkyl (meth) acrylamides which are added in protonated form or in the form of a quaternary ammonium salt. The alkyl groups bonded to the nitrogen atom preferably comprise 1 to 4 carbon atoms. Most preferably, the alkyl group is selected from methyl group and ethyl group. The aminoalkyl group includes according to a

preferred embodiment 1 to 8 carbon atoms.

Particular preference is given to using dialkylaminoethyl (meth) acrylate, dialkylaminomethyl (meth) acrylate and dialkylamino-1,3-propyl (meth) acrylates. To generate a

permanent cationic charge, the nitrogen atom of the amino group is preferably alkylated with a methyl or an ethyl group. The cationic monomers are preferably copolymerized with neutral monomers, for example

(Meth) acrylamide or alkyl (meth) acrylates, such as

Methyl (meth) acrylate.

As anionic polymers, those already mentioned above

mentioned anionic polymers are used.

In the production of paper and paperboard, the procedure is preferably such that initially an aqueous fiber suspension is provided which preferably has a solids content of more than 0.5% by weight, according to a further embodiment of more than 1% by weight. and according to yet another

Embodiment has a solids content in the range of 1 to 3 wt .-%.

To the fiber suspension, the polymer used as further component of the flocculation system, preferably a cationic polymer, is preferably added first. The addition of,

preferably cationic polymer causes flocculation of the fiber suspension, resulting in relatively large and loose Forming flakes. This large flake suspension is then preferably subjected to shear forces, thereby splitting the large flakes into microflakes which resist further exposure to shear forces. After preparation of the microflakes, the suspension

preferably no longer exposed to high shear forces.

Subsequently, the addition of the further components of the flocculation system, i. the inorganic microcomponent as well as the coacervate. The addition of the components of the flocculation system is carried out sequentially according to a preferred embodiment. Preferably, first the inorganic microcomponent and then the coacervate are added to the fiber suspension.

According to a particularly preferred embodiment

initially prepared an aqueous fiber suspension containing fibers, preferably cellulose fibers, and at least one filler. The fiber suspension is then flocculated first by addition of a polymer, preferably a cationic polymer, which serves as a further component of the flocculation system. The resulting large flakes are cut into microflakes by the flocculated

Fiber suspension is subjected to shearing forces. This can be done for example by mixing.

For the suspension of the microflakes is then the inorganic microcomponent, preferably a layered silicate, in particular bentonite, which is particularly preferably a high

Swellability given. For this purpose, the phyllosilicate or bentonite is preferably present in the sodium form, ie the exchangeable cations of the phyllosilicate or bentonite are formed by sodium ions. The amount of the inorganic microcomponent, preferably the amount of bentonite, is preferably in the range of 0.03 to 0.5 wt .-%, according to another embodiment in the range of 0.05 to 0.3 wt .-% and according to yet another more

Embodiment selected in the range of 0.08 to 0.2 wt .-%. The percentages are based on the dry weight of the fiber suspension. The addition of the inorganic

Microcomponent preferably takes place in the form of an aqueous suspension, which is particularly preferably a

FestStoffgehalt in the range of 1 to 10 wt .-% has. After the addition of the inorganic microcomponent, the

flocculated suspension preferably no longer sheared.

It then takes the addition of the coacervate, which

is preferably added in the form of a Dispiersion in which the coacervate has already formed. A Finally, the flocculated suspension is poured on a sieve in the usual way to produce a paper structure. The paper structure is then processed in the usual way to a paper or a cardboard. For this purpose, methods known to the person skilled in the art can be used.

The invention will be explained in more detail below by means of examples and with reference to the accompanying figures. Showing:

1 shows the flocculation behavior of the sample 13 as a function of time, determined for different ratios of polymeric anion / polymeric cation by determination of the absorption at a wavelength of 500 nm;

Fig. 2: the flocculation behavior of the sample 220 as a function of time, determined for various ratios of polymeric anion / polymeric cation by determination the absorption at a wavelength of 500 nm;

Addition of the coacervate occurs at 1412 s after the absorption of the PCC has stabilized;

FIG. 3 shows the flocculation behavior of the samples 205 and 210 in FIG

Dependence on time, determined by determination of the absorption at a wavelength of 500 nm;

4: a representation of the flocculation time T ₅₀ for

different coacervates; the measurement was for different ratios of polymeric anion / polymer

Cation performed;

5 shows a representation of the flocculation index as a function of the charge of the coacervate investigated;

Fig. 6: The results of dewatering experiments

Measuring methods:

Determination of the molecular weight of the polymers:

The molecular weight of the polymers is through

Size exclusion chromatography and comparison with

Standard polymers determined.

Determination of the particle size distribution

The particle size distribution is determined by light scattering with commercially available Zetasizers (3000 HS, Zetamaster S, Malvern Instruments) according to the manufacturer's instructions.

The detected laser light scattering sufficiently dilute

Suspension allows a temporal distribution of Laser intensity, with the particle size or

Particle size distribution correlates.

Determination of the zeta potential

The zeta potential is determined by means of laser Doppler anemometry (LDA). This is the electrophoretic

Migration rate of colloids or coacervates measured in suspension. From this colloid speed can be concluded that the zeta potential.

The Zetamaster S (Malvern Instruments) and the Zetasizer 3000HS (Malvern Instruments) were used.

Specific surface and pore radius distribution

The specific surface area was prepared by the BET method (a ^¬ point method using nitrogen in accordance with DIN 66131, multiple point determination) using a

automatic nitrogen porosimeter (Micromeritics, type ASAP 2010). The pore volume was determined by the BJH method (E.P. Barrett, L.G. Joyner, P.P. Hienda, J. Am. Chem. Soc. 73 (1951) 373). Pore volumes for certain

Pore radius ranges were determined by summing up incremental pore volumes, which according to BJH were determined from the

Adsorption isotherms were determined. The total pore volume refers to pores with a diameter of 2 to 7500 nm

montmorillonite

Determination of montmorillonite content over the

Methylene

The methylene blue value is a measure of the inner surface of the clay materials. a) Preparation of a tetrasodium diphosphate solution

5.41 g tetrasodium diphosphate are weighed to 0.001 g exactly in a 1000 ml volumetric flask and shaking to the mark with dist. Water filled up. b) Preparation of a 0.5% methylene blue solution

In a 2000 ml beaker, 125 g of methylene blue in about 1500 ml dest. Water dissolved. The solution is decanted off and distilled to 25 l with dist. Water filled up.

0.5 g of wet test bentonite with a known internal surface is accurate to 0.001 g in an Erlenmeyer flask

weighed. Add 50 ml of tetrasodium diphosphate solution and heat the mixture to boiling for 5 minutes. After cooling to room temperature, 10 ml of 0.5 molar H ₂ SO _{4 are} added and 80 to 95% of the expected

Final consumption of methylene blue solution added. With the

Glass rod is picked up a drop of the suspension and placed on a filter paper. It forms a blue-black spot with a colorless yard. It is now added in portions of 1 ml more Methylenblaulösung and the

Spotted sample repeated. The addition is done until the yard turns slightly light blue, so the added

Methylenblaumenge is no longer absorbed by the test bentonite. c) Testing of clay materials Testing of the clay material is carried out in the same way as for the test bentonite. From the used amount of methylene blue solution, the inner surface of the clay material can be calculated. 381 mg methylene blue / g clay correspond to a content of 100% montmorillonite according to this method. Production of the

Koazervate a) Preparation of polymer solutions General manufacturing instructions

Preparation of polymer stock solutions

Of the polymers listed in Table 1, a polymer stock solution was prepared in each case, in a concentration of 1 g of polymer / L solution, dissolved in optionally dist. Water or brine (0.2 M aqueous NaCl) adjusted to pH 7 with HCl or NaOH.

b) Production of coacervates

Coacervates were prepared by mixing together stock solutions of the cationic and anionic polymers in specific volume ratios in 50 ml volume sample jars. The coacervates were prepared per polymer combination, each with three polymer ratios. Since the molecular weight was not known for all polymers, the

Ratios set in mPK / mPA (volume). For the preparation of each 4 ml of coacervate solution, the amounts were mixed as indicated in Table 2, with always the

Cation- was added to the excess anion solution.

There were two batches each. Deionized water was used to make the first batch. The other batch was prepared using 0.2 M aqueous NaCl solution.

The sealed 50 ml test tubes were moved overnight on a shaker. After complete dissolution, the samples were outgassed at 40 ° C by ultrasound.

For the retention and drainage experiments, the coacervates summarized in Table 3 were selected.

Of the coacervates listed in Table 3, the

Particle size or the particle size distribution determined using a Zetasizer. From each sample, 2

Determinations carried out with 3 measurements each. In each case the measurement was used for the evaluation, which had the lowest polydispersity index. Table 4 shows in each case the values for the maxima of the particle size distribution. The evaluation was determined by volume, ie the percentage of coacervates formed in the given volume.

Stability of coacervate dispersion / turbidity evaluation

The samples listed in Table 3 were stored in vials sealed for 6 days at room temperature. The

Stability of the coacervates was after preparation of the

Koazervate and then evaluated daily. The evaluation listed in Table 5 was used.

The evaluation of the stability measurements is summarized in Table 6.

Determination of the zeta potential

Selected samples were used to determine the zeta potential. The values determined are summarized in Table 7.

The zeta potentials of the coacervates are all anionic, but distinct differences occur. Since the pH of the samples was adjusted, the samples were measured directly. Measurements on samples containing NaCl should not be compared to salt-free samples as NaCl strongly shields the charge of the coacervate particles. Attempts to precipitate precipitated calcium carbonate (PCC) with coacervates

Preliminary test: Decline speed

For the flocculation experiments, a suspension of precipitated calcium carbonate (PCC) in deionized water was prepared which had a concentration of 0.1% by weight. For the flocculation experiments, 20 ml of the stock solution were each filled into a sample jar. To each sample glass was then added, in a ratio coacervate / PCC of 1: 2500, the coacervates summarized in Table 3 and the

Decreasing speed of the PCC determined as a function of time. The results are summarized in Table 8.

Sample 13 had a charge ratio PK / PA = 0.66, sample 205 a charge ratio PK / PA = 0.66, sample 210

Charge ratio PK / PA = 0.33 and sample 220 a

Charge ratio PK / PA = 0.66. In addition, one was

Zero sample, to which no coacervate was added.

The samples 13 and 220 show a fast visible flocculation, while the samples 205 and 210 in the Absinkverhalten the

Zero sample (NP).

Flocculation behavior as a function of the particle charge With the coacervates listed in Table 3, the

Flocculation behavior of PCC investigated. For this purpose, 2000 μΐ of a 0.05% by weight suspension of PCC in deionized water were introduced into a quartz cuvette and the cuvette was placed in the

Measuring chamber of a UV spectrometer used. For the

Kinetic measurements, the absorption was measured at a wavelength of 500 nm. After the absorption of the PCC had stabilized, 4 μΐ of a coacervate dispersion was added at t = 1412 seconds. The dispersion had a proportion of 0.01% by weight of coacervate. This corresponds to a coacervate / PCC ratio of 1: 2500. The decrease of

Absorption is shown for the various coacervates in FIGS. 1 to 3.

Samples 13 and 220 show a short flocculation time. For samples 205 and 210, only a slight flocculation was observed, which is also due to the fact that the with the

Coacervates 205 and 210 formed flakes are very small, especially. The results of the flocculation experiments are summarized in Table 9.

For better comparability of the experiments a flocculation index is recorded in Table 9. The index is calculated

as follows :

In FIG. 4, the flocculation time T ₅₀ for the coacervates described in Table 3 is plotted against the charge of the respective coacervate. The flocculation time T ₅₀ is defined as the T ₅₀ time of the equivalence point subtracts the time of addition of the coacervate. In Figure 5, the flocculation index versus charge is plotted for the coacervates described in Table 3.

Sample 13 shows the shortest flocculation time T ₅₀ of the investigated coacervates. At a charge ratio of 0.3, the flocculation time T _{50 is} 20.6 seconds. The flocculation would therefore be completed after 41.2 seconds. The flocculation index increases slightly with increasing charge.

Sample 205 provides a complete flocculation index of 0.3, a flocculation time T ₅₀ of 82.3 seconds

Flocculation after 164.6 seconds with a load of 0.66 a bad flocculation behavior.

The flocculation behavior of the sample 210 is with a

Flocculation index of 0.2, a flocculation time T ₅₀ of 130.6

Seconds, which corresponds to a complete flocculation after 261.2 seconds at a load of 0.33 worse than that of the sample 205

The sample 220 shows, similar to the sample 13, a well visible flocculation behavior, but at significantly elevated Flocculation time. The flocculation time T ₅₀ decreases in the sample 220 with increasing charge ratio. The flocculation index shifts to higher values as the charge ratio increases, ie the flocculation behavior improves.

(Flocculation index: 0.63, flocculation time T ₅₀ : 100.3 seconds;

complete flocculation: 200.6 seconds; Charge: 0.5).

retention tests

Preparation of coacervates a) Preparation of coacervate (sample 013K-1 g / l): loading range 0.1 to 0.8

Coacervates were prepared with the polyanion "FP3230 S" and the polycation "FO 4290 PG2".

In order to investigate whether the charge of the coacervate has an influence on the flocculation, coacervates were used in one

Charge ratio range between 0.1 to 0.8 made. The details of the preparation are summarized in Table 10.

For the preparation of the coacervates in each case a stock solution of the polymeric anion and the polymeric cation in a concentration of 1 g / 1 was used. In order to achieve a complete dissolution of the polymers, the stock solutions were stirred or shaken for one day at room temperature. After the polymers had completely dissolved, it was adjusted to pH 7.0 with HCl or NaOH. To prepare the coacervates with the desired charge ratios, the stock solutions were in the ratio shown in Table 10

mixed. To ensure complete coacervate formation, incubate overnight on the shaker. b) preparation of coacervate (sample 220 - 10 g / l in 0.2 M NaCl);

Charge ratio range 0.2 to 0.5

Coacervates were prepared in a charge ratio range of 0.2 to 0.5. The polyanion "Satialgine S 1600" and the polycation "FO 4190 PG 1" were each dissolved in 0.2 M NaCl solution. Each batch was set at a volume of 220 ml. The details of the preparation of the coacervates are summarized in Table 11.

The weighed polymers were diluted to 10 g / l with a 0.2 M NaCl solution. To completely dissolve the polymers, the samples were vigorously agitated / shaken for one day.

Only after the polymers were completely dissolved, the pH adjustment was carried out with HCl or NaOH to pH 7.0. The polymer solutions were mixed in the ratio shown in Table 11 to obtain coacervates in the desired charge ratio. The coacervation takes place overnight on the shaker. c) preparation of coacervate (sample 205 - 10 g / l);

Charge Ratio: 0.66 The coacervate of sample 205 was prepared at a charge ratio of 0.66 from the polyanion "AB 995 V" and the polycation "Alcofix." The concentration of coacervate in the sample was 10 g / 1 The conditions for the preparation are shown in Table 12 summarized .

The weighed polymers were diluted to 10 g / l with deionized water. The samples were vigorously stirred / shaken at room temperature for one day so that the polymers completely dissolved. After adjustment of the pH with HCl or NaOH to pH 7.0, the two polymer solutions were mixed in the volume ratio indicated in Table 12 so that a coacervate with the desired charge ratio of 0.66 resulted. The coacervation took place overnight on the shaker. d) preparation of coacervate (sample 210-10g / l in 0.2 M NaCl);

Charge ratio: 0.33

The coacervate of sample 210 was prepared at a concentration of 10 g / l with 0.2 M NaCl from the polyanion "Sokalan CP 45" and the polycation "Alcofix" at a loading ratio of 0.33. The amounts used are summarized in Table 13.

The weighed polymers were diluted to 10 g / l with a 0.2 M NaCl solution and made strong for one day stirred / shaken to ensure complete dissolution.

The samples were then adjusted to pH 7.0 with HCl or NaOH and mixed to give the coacervates in the desired charge ratio of 0.33 in the ratios given in Table 13. Complete coacervation was on the shaker overnight.

Retention and drainage tests

The term "total retention" indicates the ratio of that used to make paper, cardboard, paperboard, paper-containing paper

Composite used dry amount of material to that in the finished paper, cardboard, cardboard, paper-containing

While the term "filler retention" refers to the ratio of

Filler content of the used for the production of paper, cardboard, cardboard, paper-containing composites dry

Indicates the amount of substance to the filler content of the finished paper, cardboard, cardboard, paper-containing composite material.

The term "fillers" in the context of the present invention in the paper present components which are present at 25 ° C as solids, which are not

Paper material fibers, in particular not pulp fibers.

Determination of retention and drainage Carrying out the retention and drainage tests

The retention and drainage experiments were carried out on a device DRF 04, the company BTG Instruments AB. It was a pulp, grade 910 BIO TOP 3, used by Mondi Austria.

The following stirring profiles or settings were selected on the device:

For retention:

Pulp suspension: 0.96% by weight of pulp, based on the total weight of the pulp suspension.

Polymer: Percol ^® 178 (Ciba AG), 0.1 wt .-% of polymer, based on the total weight of the polymer solution; freshly prepared solution.

Coacervate: 0.1% by weight of coacervate, corresponding to 50 g / t

cellulose

Stirring profile: Stir and add polymer at 750 rpm (revolutions per minute) for 3 seconds (seconds), then stir at 1400 rpm for 15 seconds, then stir and add bentonite and coacervate for 3 seconds at 750 rpm, and continue for 1200 minutes at 7000 rpm Stir, then at 400 rpm for 1 s

Recording the retention after pouring onto a sieve 24 mesh.

The device calculates the total and filler retention directly.

For drainage:

Pulp suspension: 0.95% by weight of pulp, based on the total weight of the pulp suspension.

Polymer: Percol ^® 178 (Ciba ^® AG), 0.1 wt .-% of polymer, based on the total weight of polymer solution corresponding to 100 g per tonne of pulp; freshly prepared solution. Coacervate: 0.1% by weight of coacervate, corresponding to 50 g / t

cellulose

Stirring profile: during 3s at 750 rpm and polymer addition, then stirring for 15s at 1000 rpm, then adding bentonite and coacervate for 3s at 750 rpm and stirring at 1200 rpm for 7 sec, then collecting the drainage by pouring onto a 60 mesh net.

The device calculates directly the drainage after pre-set time, d. H. after 5s, 10s and 30s.

Used materials

cellulose

It became a wood-free pulp (Mondi, Austria)

used.

bentonite

The bentonite used was soda-activated bentonite (Opazil AOG, Süd-Chemie AG).

Cationic polymers

Cationically charged polyacrylamides (PAM) from ^Ciba® AG were used. The polyacrylamides from the Percol family were particularly Percol ^® 178, used.

coacervate

It became the coacervate of sample 13 with a

Charge ratio of 0.2 used. As a comparison, the retention and drainage was determined analogously also for the Telioform system as well as for a two-component system. The Telioform system was 100 g / t pulp

Telioform added. The two-component system used only the cationic polymer and bentonite.

The results of the retention experiments are in Table 14, the results of the drainage tests are in Table 15

summarized .

Claims

1. A process for the preparation of filled paper or paperboard, wherein an aqueous fiber suspension is prepared containing fibers and at least one filler, and the fiber suspension is flocculated with a flocculation system which comprises as components at least one inorganic microcomponent and a coacervate, which at least one cationic polymer and an anionic polymer is formed, and the flocculated fiber suspension is processed into a filled paper or a filled paperboard.

2. The method of claim 1, wherein the coacervate is a

Has excess charge.

3. The method according to claim 1 or 2, wherein the anionic and the cationic polymer in a charge ratio in

Range from 0.1 to 0.95 are contained in the coacervate.

4. The method according to any one of the preceding claims, wherein first an aqueous dispersion of the coacervate

is prepared and the aqueous dispersion of coacervate is then added to the aqueous fiber suspension.

5. The method according to claim 4, wherein the dispersion of the

Coacervate has a content of coacervate in the range of 0.1 to 15 wt .-%.

6. The method according to any one of claims 4 or 5, wherein the

Coacervate dispersion contains an electrolyte.

7. The method according to any one of the preceding claims, wherein at least one of the at least contained in the coacervate a cationic and at least anionic polymers have a linear structure.

8. The method according to any one of the preceding claims, wherein the coacervate forming at least one cationic polymer and / or the at least one anionic polymer

Molecular weight of more than 50,000 g / mol.

A process according to any one of the preceding claims wherein the cationic polymer comprises cationic monomer units and the proportion of cationic monomer units in the entirety of the cationic polymer forming

Monomer units is at least 1 mol%.

1 0. The method according to any one of the preceding claims, wherein the cationic polymer is selected from the group of polyacrylamides, polyethyleneimines, polyvinylamines,

Polyethylene glycols, poly-DADMAC, as well as native polymers, especially cationic starch and chitosan.

11. The method according to any one of the preceding claims, wherein the anionic polymer comprises anionic monomer units and the proportion of the anionic monomer units of

Entity of the anionic polymer forming

Monomer units is at least 1 mol%.

1 2. The method according to any one of the preceding claims, wherein the anionic polymer is selected from the group of polyacrylates, polyacrylamides, and copolymers of

Acrylates and acrylamides, anionic starch,

Cellulosederivaten, such as carboxymethyl, -ethyl, -propylcellulose, cellulose ethers, alginates and

Carragenans, polysulfonates, polyphosphates.

13. The method according to any one of the preceding claims, wherein the filler is selected from calcium carbonate,

Titanium dioxide, talc, kaolin, diatomaceous earth, magnesium carbonate, barium sulfate, zinc sulfide and calcium silicates.

14. The method according to any one of the preceding claims, wherein the flocculation system at least one further

Flocculating component selected from at least one further anionic polymer and at least one further cationic polymer.

15. The method according to any one of the preceding claims, wherein the addition of the components of the flocculation system is carried out sequentially.

16. The method of claim 15, wherein the fiber suspension is sheared after addition of at least one component of the flocculation system.

17. The method according to any one of claims 15 or 16, wherein the coacervate is added as the last component of the flocculation system to the fiber suspension and the fiber suspension is no longer sheared after the addition of the coacervate.