CZ286834B6 - Water suspension of minerals and/or filling agents and/or pigments, process of its preparation and use thereof - Google Patents

Abstract

Aq. slurry of minerals, fillers and/or pigments with a solids content of min. 60 (wt.)% contains, as dispersant(s), amphoteric polyelectrolyte(s) (I), in which the no. of negative charges in the anionic monomer units is equal to the no. of positive charges in the cationic monomer units, which may also contain neutral monomer units; cationic polyelectrolyte(s) (II); amphoteric cationic polyelectrolyte(s) (III), in which the non-neutral monomer units have mainly positive charges; amphoteric anionic polyelectrolyte(s) (IV), in which the non-neutral monomer units have mainly negative charges; partly neutralised anionic polyelectrolyte(s) (V); and/or partly neutralised amphoteric anionic polyelectrolyte(s) (VI), in which the non-neutral monomer units have mainly negative charges. The mineral, filler and/or pigment particles have an outwardly neutral or positive charge.

Description

Technical field

The invention relates to an aqueous suspension of minerals and / or fillers and / or pigments containing > 60% by weight of solids based on dry mineral or dry filler or dry pigment, wherein the mineral or filler or pigment is dispersed by at least one dispersant.

The invention further relates to a process for the preparation of said aqueous suspension and to its use.

BACKGROUND OF THE INVENTION

'Positive charges' are understood to mean that the particles exhibit a positive ZETA potential on their surface (cf. P. Ney 'ZETA potential and mineral flotability', Applied Mineralogy 6, Springer Verlag, Wien, New York, 1973, vol. 22 and more). Analogously, this applies to the "negative charges" that occur, for example, in cellulose fiber and anionically stabilized suspensions. For neutral “charges” relative to particles, positive and negative charges externally interfere with one another. The isoelectric point need not lie at a pH of 7. The isoelectric point of the particle surfaces and amphoteric polyelectrolytes and / or their salts, partial and / or complete salts has a pH at which the positive and negative charges neutralize each other externally.

By neutral monomer units are meant monomer units which do not contain any dissociable groups (such as a -COOH group), such as ethylene groups.

These externally charged and externally neutral polyelectrolytes are defined by the number of positive or negative groups. Accordingly, in the case of amphoterics, as opposed to neutral polyelectrolytes, the number of positive charges in the cationic monomer units is equal to the number of negative charges of the anionic monomer units. In the amphoteric cationic polyelectrolytes, these non-neutral monomer units have a predominantly positive charge. In amphoteric anionic polyelectrolytes, these neutral monomer units have a predominantly negative charge.

However, this does not mean that, for example, in the case of an excess of positive charges, the polyelectrolyte is automatically electrically positive. This is because “acid strength” and “base strength” can sometimes be different. Thus, for example, the amphoteric polyelectrolyte with the same number of positive and negative groups may be electrically either positive or negative or neutral. This also applies equally to amphoteric cationic polyelectrolytes and amphoteric anionic polyelectrolytes. By shifting the pH value, the dissociation of the acidic, resp. basic groups ". Particularly at pH values between 5 and 10, the polyelectrolytes of the invention may exhibit the following charge states:

-1 CZ 286834 B6

pH 5-10 amphoter. polyelektr. cation. polyel. amf. polyel. amf. slightly anion. polyel. AND + + + + neutral neutral neutral (B) + + + = predominantly predominantly - a little a little - + C + + + + or or neutral neutral

A = possibility of an external electric charge

B = number of monomer units charged

C = charge of particles

Neutralization of negative groups by mono- and / or di- and / or trivalent cations also affects their dissociation degree and thus also the external charge state.

Anionically stabilized calcium-containing minerals such as calcium carbonate, dolomite, etc. are prepared predominantly by grinding with anionic polyacrylates, such as described in EP 0 100 947 or FR 820 806. This patent discloses that in anionically stabilized suspensions they provide partially neutralized polyacrylic acids better viscosity stability than fully neutralized. The range of neutralization described, lying between 40 and 96% neutralization, does not give satisfactory results in the cationic suspension of the invention.

The examples given in FR 820 806 show that a neutralization of less than 50% does not lead to a target, but that the optimum is a degree of neutralization of 60 to 70%. Minerals can also be suspended with amphoteric dispersing agents as described in EPO 256 6122. In these polyelectrolyte amphoterics disclosed in the published application, the isoelectric point lies deep within the acidic pH range, so that they are not suitable for the pigment and / or filler and / or mineral suspensions of the invention. In addition, only amphoteric polyelectrolytes are mentioned which contain predominantly anionic monomers in their molar monomer composition. According to the prior art, the particles exhibit a negative charge on their surface.

However, anionic stabilization is not desirable for some applications. Rather, it is appropriate to add suspensions of neutral or positively charged particles. When calcium carbonate coated with an anionic dispersant is used as filler in the paper industry, it is necessary to bind the negatively charged filler to cationic paper retention agents which are naturally negatively charged with carboxyl groups.

By neutralizing and flocculating negatively charged mineral and / or filler particles and / or pigments, in order to achieve the highest possible degree of filling and good filler retention in the paper, a negatively charged paper fiber can also be flocculated which can lead to poor paper formation and thereby causing irregular viewing of the paper. Under the current state of the art, this negative effect is hardly overcome. For this reason, dry powder products, which exhibit only weakly negative or externally neutral or weakly positive surface charges, are still used in paper production today.

However, dry-ground products are very difficult to prepare in the required fineness. In addition, there is the problem of dust formation.

-2GB 286834 B6

Cationically stabilized, i.e. surface-positively charged, partially calcium-containing minerals such as calcium carbonate, dolomite, etc. are usually prepared by dispersing in water with neutral and / or cationic protective colloids and / or cationic dispersants (cf. DE DOS 3 707 221 and DE DOS 3 730 833) or by dispersing with an agent which is a combination of a fully neutralized anionic and cationic agent as described in EP 0 278 602 A1, the latter using an amount of cationic polymer such that the particles in the suspension have a positive charge.

EP 0 278 602 also describes polyacrylic acid. Pure, non-neutralized polyakiylic acid is unsuitable since it already starts to crystallize at +20 ° C and is therefore no longer capable of dosing. Once crystallization has begun, the polymer solution must be heated to 100 ° C to redissolve the crystals.

In winter and in colder regions, production using unneutralized polyacrylic acids is unthinkable.

These methods have the disadvantage that the comminution, i.e. grinding and dispersion, must be carried out in separate steps.

According to the state of the art, the following possibilities exist:

The calcium-containing rock is ground in a dry way until the necessary fineness is achieved.

The fineness that can be achieved in this way is limited. The re-agglomeration by van der Waals forces considerably prevents grinding to a high degree of fineness. In a special step, it is then dispersed by the above-mentioned dispersing agents.

b) - the calcium-containing rock is wet-ground at a low solids content (approx. 30% by weight) without the use of grinding and dispersing aids and must be brought to the desired concentration by either filter presses, flocculants or centrifuges. In a special step, it is then dispersed with the above-mentioned dispersants.

c) - the calcium-containing mineral is wet-ground with anionic dispersing agents to the desired fineness, dried and then redispersed with the abovementioned cationic polyelectrolytes and / or protective colloids. During drying, clusters arise which cannot be completely disturbed again; results in a product less fine than it was originally. An anionic dispersing agent which does not decompose upon drying may interfere with the subsequent dispersion and cause a higher consumption of cationic polyelectrolyte.

Long-term viscosity stability cannot be achieved with the above-mentioned preparation methods a to c.

Therefore, the preparation of a suspension of minerals and / or fillers and / or pigments must necessarily be carried out at or near the consumer and spoils in a short time by increasing viscosity or sedimentation.

In many cases, a decrease in viscosity by dilution is not possible, as high concentration is of decisive importance for further processing, for example in paints in the paper industry.

Recently, efforts have been made to prepare cationically stabilized calcium-containing fillers by milling at a low solids content, as explained at Loreen Goodwin, Columbia River Carbonates, presented at TAPPI Papermaker, April 89 in Washington D.C.

-3 CZ 286834 B6

This process has the disadvantage that the solids content is limited to 45 to 50 wt. %. At higher concentrations, the viscosities are so high that the suspensions are no longer processable. Long-term viscosity stability is not given.

Due to the low solids content, the suspension tends to settle and is therefore not stable upon storage. The transport costs related to the dry product are 45% by weight of suspensions of approx. 50% more expensive than 70% by weight. These are necessary for both the manufacturer and the consumer of approx. 50% more storage capacity.

EP 0104904 discloses an aqueous suspension of mineral particles having a solids content of at least 40 wt. %. This suspension contains cationic and amphoteric polyelectrolytes with nitrogen-containing groups, and the disclosure herein does not indicate to the skilled person what the term "amphoteric polyelectrolyte" means. Rather, the amphoteric compound is misleading, since this compound has no distinct amphoteric character.

Not only the DMDAC (dimethyldiallylammonium chloride) but also the acrylamide used in the copolymer referred to as amphoteric are exclusively cationic in structure.

When purchasing aqueous suspensions, the sedimentation of dispersed mineral particles is expected within 3 to 7 days, which is not possible with a ship transport that lasts from Scandinavia to England for 4 to 7 days and it would be impossible to empty large ships that are used today. transport of this kind of goods.

The transport of such large cargoes is virtually impossible. Also, a 4-7 day train service in 56 t tankers from Austria to northern Germany is excluded for the same reasons. Not only the train, but also the boat, which is ecologically very important today.

The requirements (properties) for suspension that are desirable for consumers are as follows:

- good storage stability lasting weeks at low viscosities

- in order to maintain the necessary properties, such as the slight abrasion of papermaking screens in papermaking and smoothing screeds, it is necessary to prepare very finely divided fillers. It is the coarse fillers in paper material that are prone to dust when making photocopies, etc.

- Opacity, gloss and whiteness of papim depends strongly on the fineness and degree of filling of the papim fillers. Opacity and whiteness are crucial for the paper industry.

today, for the paper mass, minerals and / or fillers and / or pigments with an equivalent spherical particle diameter of 50 to 90 wt. % <2pm (measured on Sedigraph 5100)

- Mineral and / or fillers and / or pigments with an equivalent spherical particle diameter of up to 99 wt. % <2pm (measured on Sedigraph 5100)

- the stability of the viscosity must be locked for weeks so that during transport and storage the suspension is not destroyed by sedimentation or viscosity increase and unnecessarily high mixing costs are incurred. Storage capacities for thousands of cubic meters of such suspensions are required to ensure the production in the paper industry that can be expected.

-4GB 286834 B6

- the particles of minerals and / or fillers and / or pigments must be retained without using a large amount of retention aid. A high degree of filling of minerals and / or pigments and / or fillers must not severely limit the strength values of the produced paper.

A high degree of filling can save cellulose, which means an enormous economic gain for the paper industry.

- pigments and / or fillers and / or mineral paints must penetrate as little as possible into the paper, remain on the paper surface during application to obtain optimum fiber coverage. Cationic coating on anionic cellulose stays better on the surface,

- the highest concentration of solids must be obtained.

EP-A-O 256 312 discloses amphoterics, water-soluble polymers and their production and use as auxiliaries or dispersants for the production of highly concentrated aqueous pigment suspensions. The polymers contain acrylic or methacrylic acid.

EP-A-307 795 discloses a cationic pigment dispersion suitable for the production of a coating material for covering paper. The dispersion comprises calcium sulfate, talc and / or aluminum hydroxide as the main components, a cationic polymer or a quaternary ammonium compound as a dispersant, and a cationic polymer surrounding the particles of pigment components as a protective colloid.

US 4,533,434 discloses a dispersant for the determination of succinic anhydride. The slurries prepared with this amphoteric dispersant do not contain minerals, fillers or pigments. Paper calibrated with suspensions of this dispersant has better resistance to hot water penetration.

It is an object of the present invention to provide a suspension of fillers and / or minerals and / or pigments with a high solids content and low viscosity that are stable upon storage.

SUMMARY OF THE INVENTION

The present invention provides an aqueous suspension of minerals and / or fillers and / or pigments containing > 60% solids by weight based on dry mineral or dry filler or dry piment, wherein the mineral or filler or pigment is dispersed by at least one dispersant. SUMMARY OF THE INVENTION The aqueous suspension comprises at least one amphoteric polyelectrolyte, wherein the number of negative charges in the anionic monomer units is equal to the number of positive charges in the cationic monomer units, optionally containing additionally neutral monomer units, and / or at least one amphoteric cationic polyelectrolyte. , wherein the non-neutral monomeric units carry predominantly positive charges, and / or at least one amphoteric anionic electrolyte, wherein the non-neutral monomeric units carry predominantly negative charges, and / or at least one partially neutralized anionic polyelectrolyte, and / or at least one partially neutralized amphoteric anionic polyelectrolyte in which the non-neutral monomeric units carry predominantly negative charges,

Wherein the amphoteric, amphoteric cationic and amphoteric anionic polyelectrolytes contain quaternary ammonium groups and the filler and / or pigment and / or mineral particles carry a charge that is neutral or positive to the exterior.

The aqueous suspension of the invention preferably further comprises at least one cationic polyelectrolyte.

The aqueous suspension of the field of the invention comprises a dispersant which is a mixture

(a) at least one cationic polyelectrolyte and / or at least one amphoteric cationic polyelectrolyte in which the non-neutral monomeric units carry predominantly positive charges, and

b) at least one partially neutralized anionic polyelectrolyte and / or at least one partially neutralized amphoteric anionic polyelectrolyte, wherein the non-neutral monomeric units carry predominantly negative charges, wherein the cationic polyelectrolyte and / or the amphoteric cationic polyelectrolyte are present in an amount in which particles or or pigment carry positive charges.

The aqueous suspension according to the invention comprises an amphoteric anionic and cationic and an amphoteric cationic polyelectrolyte carrying a positive charge functional group in the ethylene backbone substituent and containing quaternary ammonium groups, carboxyl groups and / or sulfonic groups and / or acidic phosphoric acid ester groups, the substituent bearing a cationic charge is attached to the backbone via a -C (= O) NH- or -C (= O) O- group.

The aqueous suspension according to the invention preferably comprises an anionic partially neutralized and amphoteric anionic partially neutralized polyelectrolyte with carboxyl groups, wherein the anionic partially neutralized polyelectrolyte is a homopolymic and / or copolymeric polyelectrolyte.

As the amphoteric anionic and amphoteric cationic polyelectrolyte, the aqueous suspension according to the invention contains at least one compound of the formula I

- - and Ri Re R-7 r ·. l .. and Re 1 oo «9 1 z X - Y I Rz- n * -r ₄ CAn) - R3 - and

in which

R _b R ₅ , R ₆ and R ₇ denote H, and / or

-6GB 286834 B6

R 1 to R ₇ denote C _1-8 alkyl, in particular C 1-6 alkyl, preferably CH ₃ or H, and / or C ₆ aryl, especially unsubstituted,

R 8 and R ₉ denote H and / or C _1-8 alkyl, in particular C _1-8 alkyl, preferably CH ₃ and / or H, and / or C ₆ aryl, especially unsubstituted, with the substitution being preferred,

R 1 is H or CH ₃ , R ₂ and R ₃ are CH ₃ or C ₂ H ₅ , R 4 is CH ₃ to C ₄ H ₉ and its isomers,

R ₅ and R ₆ are H, R ₇ is H or CH ₃ , R 8 and R ₉ are H,

X is O or NH,

Y is CH ₂ to C ₅ H 10,

Z is -COOH and / or - (CH ₂ ) _n -COOH and / or - (CH ₂ ) _n -SO ₂ OH, where n is 1 to 18, and / or prenylene-SO ₂ OH and / or acid ester groups phosphoric acid, a + b are relative amounts of monomers in formula I in the range of 5:95 to 99: 1 and (An) 'is chloride and / or bromide and / or iodide and / or HSO ₄ ' and / or CH ₃ SO ₄ And / or nitrite.

The aqueous suspension according to the invention preferably contains compounds of formula II as polyelectrolytes

H H H i H 1 F p p. - ~ l_. u | and AND AND c = o 1 A c = o) Oii tallow - b L - C

wherein Z is the c / valence (cat) ⁺ and when c = 0, then Z = 0 and (cat) ⁺ is an alkali metal and / or alkaline earth metal cation and / or an amine and / or alkanolamine and / or quaternary ammonium cation.

(An) 'is chloride, bromide, iodide, HSO ₄ ', CH ₃ SO ₄ 'or nitrite, wherein the polyelectrolytes a, b, c are present in the following ratios:

anionic amphoteric amphotemia amphoteric cationic a = 49 to 47 mol% b + c = 51 to 53 mol% a = 50 mole% b + c = 50 mole% a = 51 to 80 mol% b + c = 49 to 20 mol%

The aqueous suspension of the invention preferably comprises compounds of formula II wherein Z is partially neutralized with alkali and / or alkaline earth cations, the degree of neutralization being in the range of 1 to 99 mol%.

The aqueous suspension according to the invention preferably contains compounds of the formula II in which the degree of neutralization of the substituent Z with alkali metal cations is in the range of 1 to 25 mol%.

Suitably, the aqueous suspension of the invention comprises compounds of formula II wherein the substituent Z is completely neutralized when the cations are bivalent cations, trivalent cations, NH 4, primary, secondary or tertiary amines or quaternary ammonium ions.

In another embodiment, the aqueous suspension of the invention comprises compounds of formula Π wherein Z is non-neutralized.

In another embodiment of the invention, the aqueous suspension comprises polyelectrolytes having a molar ratio of anionic charge to cationic charge in the range of 55:45 to 51:49.

Another embodiment of the invention is an aqueous suspension which comprises polyelectrolytes, all of which have a neutralization degree of the anionic component, with the exception of pure cationic electrolytes, in the range of 0.1 to 100 mol% when neutralized by alkaline earth cations.

Another embodiment of the invention is an aqueous suspension which contains at least one compound of formula III as a cationic electrolyte

R3 R2

I ι c — c-- ι i Re C = O I

X I Ϋ I

R 2 -N ⁺ -R 4

R3

Clil)

(Cftn) 'in which

R 1, R 5 and R 6 denote H, and / or

R 1 to R 5 denote C 1-6 alkyl and / or C 1-6 aryl,

R 5 is optionally a group

-CXYN ⁺ -R 3

AND

R2 wherein X is O and / or NH,

Y is -CH? - and -C5H10-, n is 20 to 3000 and (An) ^_ is a chloride and / or bromide and / or iodide and / or CH ₃ SO / and / or nitrite.

-8EN 286834 B6

Yet another embodiment of the invention is an aqueous suspension which contains at least one compound of formula IV as an anionic partially neutralized polyelectrolyte

Rt Ra c --- i R3 Z <IV)

+ £ Ka ^at Jv in which

Z is -COOH and / or - (CH 2) _n COOH and / or - (CH ₂ ) _n -SO ₂ OH and / or p-phenylene-SO ₂ OH and / or an acidic ester group of phosphoric acid,

R 1 is H or CH ₃ ,

R ₂ and R ₃ denote H and / or C 1-6 alkyl and / or C ₆ aryl, and R ₂ or R ₃ optionally denotes Z, when Z is -COOH, u is a charge of +1 and / or +11 and / or + III,

Ka is an alkali metal and / or alkaline earth metal ion, w is 59 to 95 mol% for the number of Z in the monomer, v is 5 to 41 mol% divided by u and n is 1 to 12.

A further embodiment of the invention is an aqueous suspension comprising an anionic polyelectrolyte and / or an amphoteric anionic polyelectrolyte in which 1 to 70 mol% of the acid groups are neutralized, the specific viscosity "Eta" of the partially neutralized anionic polyelectrolyte and / or amphoteric anionic polyelectrolyte and and / or the amphoteric cationic polyelectrolyte, measured in the form of complete salt, is in the range of 0.2 to 1.0 and the degree of polymerization of the cationic polyelectrolyte and / or the amphoteric cationic polyelectrolyte in admixture with the partially neutralized anionic polyelectrolyte and / or amphoteric anionel partially neutralized the cut-off viscosity is in the range of 5 to 50 ml / g and the cut-off viscosity of the cationic and / or amphoteric cationic polyelectrolyte used in the aqueous suspension is in the range of 9.2 to 48.5 ml / g.

The aqueous suspension of the invention preferably comprises an amphoteric anionic and amphoteric neutral and amphoteric cationic polyelectrolyte having a degree of polymerization in the range of 5 to 150 mPa.s, measured by viscosity.

The aqueous suspension according to the invention preferably contains 97.0 to 99.97% by weight of minerals and / or fillers and / or pigments or water and 0.03 to 3.0% by weight of amphoteric polyelectrolytes with a solids content of 60 to 80% by weight, individually for dry material and dry filler and dry pigment.

In another embodiment of the invention, the aqueous suspension comprises 97.0 to 99.89% by weight of minerals and / or fillers and / or pigments and water and 0.11 to 3.0% by weight of a mixture of cationic and / or amphoteric cationic and partially neutralized anionic and / or or partially neutralized

The amount of solids is 60-80% by weight, based on the dry mineral and the dry filler and the dry pigment.

Yet another embodiment of the invention is an aqueous suspension comprising minerals and / or fillers and / or pigments comprising elements of a second and / or a third main group and / or a fourth subgroup of the Periodic Table of the Elements.

The aqueous suspension according to the invention preferably contains natural calcium carbonate, precipitated calcium carbonate and / or marble, chalk, dolomite and / or dolomite containing calcium carbonate as minerals and / or fillers and / or pigments.

The invention also relates to a process for the preparation of the aqueous suspension according to the invention. The essence of this causes in that

(a) an aqueous suspension of minerals and / or fillers and / or pigments is milled wet with a mixture of dispersants and a mixture of milling aids,

(b) polyelectrolytes of the invention prior to milling of the amphoteric; or

(c) a portion of the amphoteric polyelectrolytes of the invention is added prior to milling; and

d) part of the amphoteric polyelectrolytes of the invention is added during grinding, and / or

e) a portion of the amphoteric polyelectrolytes of the invention is added after grinding, or is added

(a) an aqueous suspension of minerals and / or fillers and / or pigments is wet milled together with a mixture of dispersants and a mixture of grinding aids,

(b) add part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes prior to grinding; and

(c) part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes is added during grinding, and / or

(d) part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes is added after grinding; and

(e) the cationic and / or amphoteric cationic polyelectrolyte is added prior to grinding, or

(f) part of the cationic and / or amphoteric cationic polyelectrolytes before grinding; and

(g) a portion of the cationic and / or amphoteric cationic polyelectrolytes is added during grinding, and / or

h) a portion of the cationic and / or amphoteric cationic polyelectrolytes is added after grinding.

The invention furthermore relates to the use of an aqueous suspension of minerals and / or fillers and / or pigments in papime production and surface treatment, pigmentation of the papim surface in a papim sizing press and in papim lubrication, pre-lubrication or opaque lubrication. lubrication process, when sanding wood to prevent wood breakage, in lubrication waste to prevent wood breakage, to control resin (pitch) in paper pulp, in the water cycle of the paper machine to reduce the need for chemical

In order to flocculate anionically stabilized suspensions of pigments and / or minerals and / or fillers in papermaking, or flocculate and immobilize the paints to be coated.

Surprising and unpredictable was the fact that the amphoteric polyelectrolytes of the invention, in which the filler and / or pigment and / or mineral particles carry just neutral or positive charges against the outside, provide, unlike the prior art, a very good viscosity stability over a long period of time. low viscosity and yet do not show sedimentation of the mineral particles although not mixed.

Hereinafter, amphoteric polyelectrolytes in which the number of negative charges of anionic monomer units is equal to the number of positive charges of cationic monomer units and amphoteric cationic polyelectrolytes and amphoteric anionic polyelectrolytes are briefly referred to as amphoteric polyelectrolytes of the invention. Amphoteric polyelectrolytes in which the number of negative charges of anionic monomeric units is equal to the number of positive charges of cationic monomeric units will be briefly referred to as "amphoteric".

Within the scope of the invention, it may be advantageous if at least a part of the amphoteric polyelectrolytes is partially neutralized.

Preferably, the amphoteric anionic and amphoteric cationic polyelectrolyte and the amphoteric polyelectrolyte, in which the number of negative charges of the anionic monomer units is equal to the number of positive charges of the cationic monomer units, carry a positive charge functional group in the ethylene backbone substituent.

It is further preferred that the substituent carrying a cationic charge is attached to the backbone by an OHO group

II III

--- C — N— or C — O—.

The latter group is particularly suitable.

It is further preferred that the amphoteric polyelectrolytes of the invention comprise quaternary ammonium groups, carboxyl groups and / or sulfonic acid and / or phosphoric acid ester groups.

Preferred as amphoteric polyelectrolytes according to the invention are one or more compounds from the group of the following compounds corresponding to the general formula:

-11EN 286834 B6

and (A _n ) may be chloride and / or bromide and / or iodide and / or HSO ₄ 'and / or CH ₃ SO ₄ and / or nitrite, wherein

R 1, R ₅ , R ₆ and R ₇ preferably represent hydrogen and / or

R 1 to R ₇ can be alkyl, preferably C 1 -C ₁₈ alkyl, particularly preferably C 1 -C ₆ , optimally -CH ₃ and / or

- aryl, preferably 6-membered ring, particularly preferably unsubstituted 6-membered ring,

R _g and R ₉ may be

- H and / or alkyl, preferably C 1 -C ₁₈ alkyl, particularly preferably C 1 -C ₆ , most preferably -CH ₃ or H

- aryl, preferably a 6-membered ring, especially an unsubstituted 6-membered ring,

R ₈ or R ₉ may also be

O

II

-COH when

O

II

Z = is -COH,

X = O and / or N-H,

Y = -CH2-to-C5H10-,

O

II

Z = -COH and / or

O

II

4CH ₂₎ n-COH, and / or

-12GB 286834 B6

O

II

- (CH 2) _n -S = O and / or

OH

and / or the acidic phosphoric acid ester residue and n may be 1-18.

Z may be partially neutralized by single, bivalent and / or trivalent cations.

According to the invention, alkali and / or alkaline earth and / or alkaline earth cations are preferred, with alkaline earth cations being preferred. Ca ** and / or Mg ** and / or Sr ** are particularly preferred, Ca ** and / or Mg ** are particularly preferred.

The neutralization stage of Z is in the range of from 1 to 99 mol%, preferably from 50 to 98 mol%, preferably from 70 to 97 mol%, and particularly preferably from 95 mol%, based on Z in b.

In the case of neutralization with a monovalent cation such as K * and / or Na * and / or Li *, the neutralization degree Z is 1 to 99 mol%, preferably 1 to 50 mol%, preferably 1 to 25 mol% and particularly preferably 25 mol%, Z v b.

Z can also be fully neutralized when the cation is bivalent and / or trivalent or is NH4 *, prim. harmful.

Z may also be neutralized.

When R _g or R _{9 do} not represent -COOH, and when amphoteric anionic polyelectrolytes are used in combination with amphoteric cationic polyelectrolytes and the particles are thus neutral or exhibit positive surface charges, they are a and b in the following ratios:

amphotemia amphotemia amphotemia anionic cationic a = 5-49 mol% a = 50 mol% a = 51-99 mol% b = 51-95 mol% b = 50 mol% b = 49-1 mol%

wherein n = 1-18 and (A _n ) may be chloride and / or bromide and / or iodide, and / or HSO ₄ and / or CH ₃ SO ₄ and / or nitrite.

-13GB 286834 B6

Further preferred are the following mixtures:

amphotemia amphotemia amphotemia anionic cationic a = 47-49 mol% and - 50 mol% a = 51-80 mol% b = 51-53 mol% b = 50 mol% b = 49-20 mol%

wherein n = 1-18 and (A _n ) may be chloride and / or bromide and / or iodide, and / or HSO ₄ and / or CH ₃ SO ₄ and / or nitrite.

When R 8 or R ₉ is -COOH and when amphoteric anionic polyelectrolytes are used in combination with amphoteric cationic polyelectrolytes and the particles are thus neutral or exhibit positive surface charges, they are a and b in the following ratios:

amphotemia amphotemia amphotemia anionic a = 10-66 mol% a = 66.66 mol% cationic a = 67-99 mol% b = 34-90 mol% b = 33.33 mol% b = 1-33 mol%

wherein n = 1-18 and (A _n ) may be chloride and / or bromide and / or iodide, and / or HSO 4 and / or CH 3 SO 4 and / or nitrite.

Further preferred are the following mixtures:

amphotemia amphotemia amphotemia anionic cationic a = 64-66 mol% a = 66.66 mol% a = 67-90 mol% b = 34-36 mol% b = 33.33 mol% b = 10-33 mol%

wherein n = 1-18 and (A _n ) may be chloride and / or bromide and / or iodide, and / or HSO ₄ and / or CH ₃ SO ₄ and / or nitrite.

It is particularly preferred that the amphoteric polyelectrolytes of the invention are compounds that correspond to this general formula wherein:

R 1 = H or -CH ₃

R ₂ -, -CH ₃ or -C ₂ H ₅

R ₃ ⁼ —CH ₃ or —C ₂ H ₃

R 4 = -CH ₃ to -C ₄ H ₉ and isomers

X = One or N-H

Y = -CH ₂ -to-C ₅ H 10 -

_R and R₆ = H

R 7 = H or -CH ₃

R 8 and R ₉ ⁼ H

It is most preferred that (A _n -) is Cl a

Y = - (CH ₂ ) 3 -.

-14GB 286834 B6

According to the invention, an amphoteric means anionic that the anionic charges predominate in camphotem polyelectrolytes over cationic charges.

Amphoteric cationic means that cationic charges in amphoteric polyelectrolytes predominate over anionic charges.

According to the invention, an amphoteric slightly anionic or cationic means that in the amphoteric polyelectrolytes there are only a slight excess of positive or negative polyelectrolytes. negative charges. An amphoteric slightly anionic means that the ratio of anionic charge to cationic charge is in the range of 55: 45 to 51: 49 mol%.

Amphoteric slightly cationic means that the ratio of anionic charge to cationic charge is in the range of 45: 55 to 49: 51 mol%.

It should be pointed out that the terms "weakly" and "lightly" are used synonymously in this application.

Polyelectrolytes according to the following formula are particularly preferred

com = ---------------- if c = 0, then z = 0 valence (Kat) ⁺

Where (Cat) ⁺ = Cations of alkali metals and / or alkaline earths and / or alkaline earth metals and / or amines and / or alkanolamines and / or quaternary ammonium cations (A _n ) '= chloride, bromide, iodide, HSO ₄ ', CH _S ~ SO ₄ and / or nitrite and where ratios aabacv polyelectrolytes according to the invention as follows:

amphotemia amphotemia amphotemia slightly anionic cationic a = 49-47 mol% a = 50 mol% a = 51-80 mol% b + c = 51-53 mole% b + c = 50 mole% b + c = 49-20 mol%

where n = 1-18

Particularly preferred are the polyelectrolytes of this general formula,

Where (Kat) ⁺ = alkali metal and / or alkaline earth cations (A _n ) = chloride, bromide, iodide, HSO ₄ , CH ₃ SO ₄ and / or nitrite, and wherein the aabac ratios of the polyelectrolytes of the invention are as follows:

slightly anionic amphoteric a = 49-48 mol% b + c = 51-52 mol% amphoteric a - 50 mol% b + c = 50 mol% amphoteric cationic a = 51-70 mol% b + c = 49-30 mol% C

and where z = -----------------.

valency (Kat) ⁺

Further, a and b and c in the polyelectrolytes of the invention are preferably in the following ratios:

amphotemia amphotemia amphotemia slightly anionic a = 49-47 mol% a = 50 mol% cationic a = 51-80 mol% b + c = 51-53 mole% b = 0-50 mole% c = 50-0 mole% b + c = 49-20 mol%

Particularly preferred are the polyelectrolytes of this general formula wherein (Kat) ⁺ = alkaline earth cations (A _n ) - chloride, bromide, iodide, HSO ₄ ', CH ₃ SO ₄ and / or nitrite and wherein the aabac ratios are in the polyelectrolytes of the invention following:

amphoteric slightly anionic a = 49-48 mol% b + c = 51-52 mol% amphoteric a = 50 mol% b = 0-25 mol% c = 25-50 mol% amphoteric cationic a = 51-70 mol% b + c = 49-30 mole% c

and where z = -----------------.

valency (Kat) ⁺

Further preferred are polyelectrolytes of the general formula wherein (KAT) ⁺ = Na ⁺ , K ⁺ , Li ⁺

Ca ²⁺ , Mg ²⁺ (A _n ) = chloride, bromide, iodide, HSO ₄ , CH ₃ SO ₄ and / or nitrite and wherein the ratios of a and b in the polyelectrolytes of the invention are as follows:

-16E 286834 B6 Amphotemia Amphotemia slightly anionic a = 49-48.5 mol% a = 50 mol% b + c = 51-51.5 mol% b + c = 50 mol% amphotemia cationic a = 51-60 mol% b + c = 49-40 mole% c

and where z = —--------------.

valency (Kat) ⁺

The most favorable results are obtained with the polyelectrolytes of the invention corresponding to this general formula wherein (K a) ⁺ = alkali metal cations (A _n ) - = halide anions and wherein the ratios a and b in the polyelectrolytes of the invention are as follows:

amphoteric slightly anaotic a = 49 mol% b = 51 mol% c = <1 mol% amphoteric a = 50 mol% b = 50 mol% c = <1 mol% amphoteric cationic a = 51 mol% b = 49 mol% c = <1 mol% c

and wherein z = ---------------.

valency of (cat) ⁺

Further preferred are polyelectrolytes of the formula wherein the amphoteric is slightly anionic a = 49-48.5 mol% b + c = 51-51.5 mol% amphoteric a = 50 mol% b = 0-10 mol% c = 40-50 mol % amphoteric cationic a = 51-60 mol% b + c = 49-40 mol% c

and where z = -----------------.

valency (Kat) ⁺

Absolutely most favorable results are obtained with the polyelectrolytes of the invention corresponding to this general formula in which (Kat) ⁺ = alkaline earth cations (A _n ) '= halide ions and wherein the aabac ratios of the polyelectrolytes of the invention are as follows:

-17E 286834 B6 amphoteric slightly anionic amphoteric a = 49 ml% b = 2 mol% c = 49 mol% amphoteric c = a = 51 mol% b = 2 mol% c = 47 mol% c

and where z = ----------------.

valency (Kat) ⁺

Preference is further given to mixtures of amphoteric cationic polyelectrolytes and amphoteric polyelectrolytes in which the number of cationic monomer units is equal to the number of anionic monomer units according to the above general formula wherein (Kat) ⁺ = Cations of alkali metals and / or alkaline earths and / or alkaline earth metals and / or amines and / or alkanolamines and / or quaternary ammonium cations (A _n ) - = chloride, bromide, iodide, HSO ₄ -, CH ₃ SO ₄ - and / or nitrite and wherein the aabac ratios of the polyelectrolytes of the invention are as follows:

amphoteric a = 50 mol% b + c = 50 mol% amphoteric cationic a - 70-99 mol% b + c = 30-1 mol%

In the mixture according to the invention, the ratios a and b and c of the polyelectrolytes according to the above general formula are further preferred:

amphoteric a = 50 mol% b + c = 50 mol% cationic a = 75-98 mol% b + c = 25-2 mol%, preference is given to:

amphoteric a = 50 mol% b + c = 50 mol% amphoteric cationic a = 80-97 mol% b + c = 20-3 mol%, further preferred are:

amphoteric a = 50 mol% b + c = 50 mol% amphoteric cationic a = 90-96 mol% b + c = 10-4 mol%

In particular, the following shall be preferred:

amphoteric a = 50 mol% b + c = 50 mol% amphoteric cationic a = 95 mol% b + c = 5 mol%.

Preference is further given to mixtures of amphoteric slightly anionic and amphoteric cationic polyelectrolytes according to the above general formula, wherein (K a) ⁺ = Cations of alkali metals and / or alkaline earths and / or alkali metals and / or amines and / or alkanolamines and / or quaternary ammonium cations (A _n ) = chloride, bromide, iodide, HSO ₄ , CH ₃ SO ₄ and / or nitrite and wherein the ratios of a and b in the polyelectrolytes of the invention are as follows:

amphoteric slightly anionic a = 47-49 mol% b + c = 51-53 mol% amphoteric slightly anionic a = 48 ^ 49 mol% b + c = 51-52 mol% amphoteric cationic a - 70-99 mol% b + c = 30-1 mol%, amphoteric cationic a = 75-98 mol% b + c = 25-2 mol%, preference is given to:

amphoteric amphoteric slightly anionic a = 48,5-49 mol% cationic a - 80-97 mol% b + c = 51-51,5 mol% b + c = 20-3 mol%, in particular:

amphoteric slightly anionic a = 49 mol% b + c = 51 mol% amphoteric cationic a = 95 mol% b + c = 5 mol%.

Preference is further given to mixtures of amphoteric, slightly cationic and amphoteric cationic polyelectrolytes according to the above general formula, wherein (Kat) ⁺ = Cations of alkali metals and / or alkaline earth metals and / or alkaline earth metals and / or amines and / or alkanolamines and / or quaternary ammonium cations (A _n ) = = chloride, bromide, iodide, HSO ₄ -, CH ₃ SO ₄ - and / or nitrite and wherein the ratios a and b in the polyelectrolytes of the invention are as follows:

286834 B6 slightly cationic a = 51-53 mol% b + c = 49-47 mol% cationic amphoteric a = 80-97 mol% b + c = 20-3 mol%, preference is given to:

slightly cationic amphoteric a - 51-52 mol% b + c = 49-48 mol% amphoteric cationic a - 90-96 mol% b + c = 10-4 mol%, in particular:

amphoteric slightly cationic a = 51 mol% b + c = 49 mol% amphoteric cationic a = 95 mol% b + c = 5 mol%.

Preferred is the neutralization degree of anionic components in the cationic and amphoteric weakly anionic and amphoteric weakly cationic and amphoteric polyelectrolytes of alkaline earth metal cations, especially with Ca ⁺⁺ and / or Mg **, 0.1 to 100 mol%, more preferably 50 to 100 mol% , and preferably 70 to 99 mol%, most preferably 98 mol%, or the anionic components are not neutralized.

Preferred is the neutralization degree of anionic components in cationic and amphoteric weakly anionic and weakly cationic and amphoteric polyelectrolytes with monovalent cations of 0.1 to 100 mol%, more preferably 0.1 to 50 mol%, and preferably 0.1 to 39 mol%, or 0.1 to 30 mol%, further preferably 0.1 to 35 mol%, or 0.1 to 25 mol%, or 0.1 to 15 mol%, and most preferably <1 mol%, or the anionic components are not neutralized. When divalent cations such as Ca ** and Mg ** are used, the neutralization degree is preferably> 90%. A neutralization degree of > 90% with Ca ** is according to the invention better than a neutralization degree < 1% sNa *.

It is preferred that the polymerization degree of the polyelectrolytes of the invention measured by their viscosity in an aqueous solution at a 32% concentration is in the range of 5 mPa.s to 150 mPa.s. A viscosity in the range of 15 mPa.s to 100 mPa.s is particularly preferred, with a range of 25 mPa.s to 70 mPa.s being particularly preferred.

For a mixture of amphoteric cationic polyelectrolytes and amphoteric lightly cationic polyelectrolytes and / or amphoteric polyelectrolytes and / or amphoteric lightly anionic polyelectrolytes, it is further preferred that the polymerization degree of amphoteric cationic polyelectrolytes (measured by their g / ml viscosity range) g, preferably in the range from 15 ml / g to 40 ml / g, particularly preferably from 25 ml / g to 35 ml / g and the polymerization degree of amphoteric slightly cationic polyelectrolytes and amphoteric polyelectrolytes and amphoteric slightly anionic polyelectrolytes measured by their viscosity in aqueous solution at 32 wt. the concentration is in the range from 5 to 150 ml / g, preferably from 15 to 100 ml / g, particularly preferably from 25 to 70 ml / g.

Preferably, the dispersing agent comprises one or more amphoteric polyelectrolytes in which the number of negative charges in the anionic monomer units is equal to the number of positive charges in the cationic monomer units.

-20GB 286834 B6

Preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric cationic polyelectrolytes in which the non-neutral monomer units carry predominantly positive charges.

Preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric, slightly cationic polyelectrolytes, in which the non-neutral monomeric units carry predominantly positive charges.

Preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric cationic polyelectrolytes in which the nonneutral monomeric units carry predominantly positive charges and one or more amphoteric anionic polyelectrolytes in which the nonneutral monomeric units carry predominantly negative charges.

Preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric, slightly cationic polyelectrolytes in which the nonneutral monomeric units carry predominantly positive charges and one or more amphoteric anionic polyelectrolytes in which the nonneutral monomeric units carry predominantly negative charges.

Preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric cationic polyelectrolytes in which the non-neutral monomer units carry predominantly positive charges and one or more amphoteric, slightly anionic polyelectrolytes in which the non-neutral monomer units carry predominantly negative charges.

Preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric, slightly cationic polyelectrolytes in which the non-neutral monomer units bear predominantly positive charges and one or more amphoteric, slightly anionic polyelectrolytes in which the non-neutral monomer units carry predominantly negative monomer units.

Preferably, the dispersing agent comprises one or more amphoteric cationic polyelectrolytes in which the non-neutral monomer units carry predominantly positive charges.

Preferably, the dispersing agent comprises one or more amphoteric cationic polyelectrolytes and one or more amphoteric, slightly cationic polyelectrolytes in which the non-neutral monomer units bear predominantly positive charges.

Preferably, the dispersing agent comprises one or more amphoteric, slightly cationic polyelectrolytes in which the non-neutral monomer units bear predominantly positive charges.

Further preferably, the dispersing agent comprises a mixture of one or more amphoteric cationic polyelectrolytes in which the non-neutral monomeric units bear predominantly positive charges and one or more amphoteric anionic polyelectrolytes in which the non-neutral monomeric units bear predominantly negative charges.

Further preferably, the dispersant comprises a mixture of one or more amphoteric slightly cationic polyelectrolytes in which the non-neutral monomeric units bear predominantly positive charges and one or more amphoteric anionic polyelectrolytes in which the non-neutral monomeric units bear predominantly negative charges.

Further preferably, the dispersant comprises a mixture of one or more amphoteric cationic polyelectrolytes in which the non-neutral monomeric units carry predominantly positive charges and one or more amphoteric slightly anionic polyelectrolytes in which the non-neutral monomeric units carry predominantly negative charges.

-21EN 286834 B6

Further preferably, the dispersing agent comprises a mixture of one or more amphoteric, slightly cationic polyelectrolytes in which the non-neutral monomeric units bear predominantly positive charges and one or more amphoteric slightly anionic polyelectrolytes in which the non-neutral monomeric units bear predominantly negative charges.

Further preferably, the dispersing agent comprises a mixture of one or more amphoteric polyelectrolytes and one or more amphoteric, slightly anionic polyelectrolytes, in which the non-neutral monomer units carry predominantly negative charges.

Further preferably, the dispersing agent comprises one or more amphoteric slightly anionic polyelectrolytes in which the non-neutral monomer units carry predominantly negative charges.

The filler particles exhibit a neutral or slightly positive surface charge when using amphoterics, slightly anionic polyelectrolytes, despite a slight excess of negative charge (carboxyl group). This is probably because some of the carboxyl groups are so strongly neutralized by Ca ⁺⁺ ions that they do not dissociate more and therefore act neutrally against the outside. As a result, dissociated cationic groups predominate and the filler particles do not exhibit a negative charge, despite the excess of carboxyl groups in the dispersant proper.

This is particularly the case at a ratio of 51-53 mol% carboxyl groups to 47-49 mol% quaternary ammonium groups in the polymer molecule.

Further, a ratio of 51 to 52 mol% of carboxyl groups to 49 to 48 mol% of quaternary ammonium groups in the polymer molecule is preferred.

Particular preference is given to a ratio of 51 mol% carboxyl groups to 49 mol% quaternary ammonium groups in the polymer molecule.

Preferably, the dispersing agent comprises 0 to 100 wt. % of the first amphoteric polyelectrolytes and 100 to 0 wt. % of the second amphoteric polyelectrolytes.

Further preferably the dispersing agent comprises a mixture of 0.1 to 99.9 wt. % of one or more amphoteric polyelectrolytes and 99.9 to 0.1 wt. % of one or more amphoteric cationic polyelectrolytes.

More preferably, the dispersing agent comprises a mixture of 50 to 99.9 wt. %, and 80 to 99.9 wt. 10 to 50 wt. % and 10 to 30 wt. %, one or more amphoteric polyelectrolytes and 0.1 to 50 wt. %, optionally 0.1 to 20 wt. %, and 50 to 90 wt. %, and 70 to 90 wt. % of one or more amphoteric cationic polyelectrolytes.

Further preferably the dispersing agent comprises a mixture of 0.1 to 99.9 wt. % of one or more amphoteric polyelectrolytes and 99.9 to 0.1 wt. % of one or more amphoteric slightly cationic polyelectrolytes.

Further preferably, the dispersing agent comprises a mixture of 0.1 to 99.8 wt. % of one or more amphoteric polyelectrolytes and 0.1 to 99.8 wt. %, preferably 0.1 to 49.8 wt. % of one or more amphoteric cationic polyelectrolytes and 0.1 to 99.8 wt. %, preferably 0.1 to 10

49.8 wt. % of one or more amphoteric anionic polyelectrolytes.

Further preferably the dispersing agent comprises a mixture of 0.1 to 20 wt. % of one or more amphoteric polyelectrolytes and 60 to 79.9 wt. % of one or more amphoteric cationic polyelectrolytes and 0.1 to 20 wt. % of one or more amphoteric anionic polyelectrolytes.

-22EN 286834 B6

Further preferably, the dispersing agent comprises a mixture of 0.1 to 99.8 wt. % of one or more amphoteric polyelectrolytes and 0.1 to 99.8 wt. %, preferably 0.1 to 49.8 wt. % of one or more amphoteric slightly cationic polyelectrolytes and 0.1 to 99.8 wt. %, preferably 0.1 to 10

49.8 wt. % of one or more amphoteric anionic polyelectrolytes.

Further preferably, the dispersing agent comprises a mixture of 0.1 to 99.8 wt. % of one or more amphoteric polyelectrolytes and 0.1 to 99.8 wt. %, preferably 0.1 to 49.8 wt. % of one or more amphoteric cationic polyelectrolytes and 0.1 to 99.8 wt. %, preferably 0.1 to 10

49.8 wt. % of one or more amphoteric slightly anionic polyelectrolytes.

Further preferably, the dispersing agent comprises a mixture of 0.1 to 99.8 wt. % of one or more amphoteric polyelectrolytes and 0.1 to 99.8 wt. % of one or more amphoteric slightly cationic polyelectrolytes and 0.1 to 99.8 wt. % of one or more amphoteric slightly anionic polyelectrolytes.

Further preferably, the dispersing agent comprises 0 to 100 wt. % first amphoteric cationic polyelectrolytes and 0 to 100 wt. % of the second amphoteric cationic polyelectrolytes.

Further preferably, the dispersing agent comprises from 0.1 to 99.9 wt. % of first amphoteric slightly cationic polyelectrolytes and 0.1 to 99.9 wt. % of the second amphoteric slightly cationic polyelectrolytes.

Further preferably, the dispersing agent comprises 50 to 99.9 wt. %, and 70 to 99.9 wt. % of one or more amphoteric cationic polyelectrolytes and 0.1 to 50 wt. %, optionally 0.1 to 30 wt. % of one or more amphoteric anionic polyelectrolytes.

Further preferably, the dispersing agent comprises a mixture of 90 to 99.9 wt. %, and 75 to 90 wt. % and 80 wt. % of one or more amphoteric cationic polyelectrolytes and 0.1 to 10 wt. % and 25 to 10 wt. % and 20 wt. % of one or more amphoteric anionic polyelectrolytes.

Further preferably, the dispersing agent comprises a mixture of 80 to 99.9 wt. % of one or more amphoteric slightly cationic polyelectrolytes and 0.1 to 20 wt. % of one or more amphoteric anionic polyelectrolytes.

Further preferably the dispersing agent comprises a mixture of 0.1 to 99.9 wt. % of one or more amphoteric cationic polyelectrolytes and 99.9 to 0.1 wt. % of one or more amphoteric slightly anionic polyelectrolytes.

Further preferably, the dispersing agent comprises 50 to 99.9 wt. %, and 70 to 90 wt. %, or 75 wt. % of one or more amphoteric cationic polyelectrolytes and 0.1 to 50 wt. %, optionally 10 to 30 wt. % and 25 wt. % of one or more amphoteric slightly anionic polyelectrolytes.

Further preferably, the dispersing agent comprises 0.1 to 99.9 wt. % of one or more amphoteric slightly cationic polyelectrolytes and 99.9 to 0.1 wt. % of one or more amphoteric slightly anionic polyelectrolytes.

Further preferably the dispersing agent comprises a mixture of 0.1 to 99.9 wt. %, and optionally 50 to 50%

99.9 wt. % of one or more amphoteric polyelectrolytes and 0.1 to 99.9 wt. %, optionally 0.1 to 50 wt. % of one or more amphoteric slightly anionic polyelectrolytes.

Further preferably, the dispersing agent comprises 0 to 100 wt. % first and 0 to 100 wt. % of the second amphoteric slightly anionic polyelectrolytes.

-23EN 286834 B6

According to the invention, the minerals and / or fillers and / or fillers contain, respectively. pigments in particular elements of the second and / or third major groups and / or of the fourth minor group of the periodic system of elements. Preferably, minerals and / or fillers and / or pigments containing calcium and / or silicon and / or aluminum and / or titanium are used, with calcium and carbonate containing minerals and / or fillers and / or pigments being preferred. Of particular interest are natural calcium carbonate and / or precipitated calcium carbonate and / or marble and / or chalk and / or dolomite and / or dolomite-containing calcium carbonate.

The aqueous suspension preferably consists of 97.0 wt. % to 99.97 wt. % of minerals and / or fillers and / or pigments and water, and 0.03 wt. % to 3.0 wt. % of amphoteric polyelectrolytes according to the invention, with a solids content of 60 to 80 wt. %, based on dry mineral, respectively. dry filler, resp. dry pigment.

It is further preferred that the aqueous suspension consists of 98.5 wt. % to 99.95 wt. % of minerals and / or fillers and / or pigments and water, and 0.05 wt. % to 1.5 wt. % of amphoteric polyelectrolytes according to the invention, with a solids content of 65 to 77 wt. %, based on dry mineral, respectively. dry filler, resp. dry pigment.

Further, a good result is obtained when the aqueous suspension consists of 98.8 wt. %, up to 99.90 wt. % of minerals and / or fillers and / or pigments and water, and 0.1 wt. % to 1.2 wt. % of amphoteric polyelectrolytes according to the invention with a solids content of 67 to 76 wt. % based on dry mineral, respectively. dry filler, resp. dry pigment.

Excellent results are obtained when the aqueous suspension consists of 99.5 wt. %, respectively.

98.8 wt. %, respectively. 99.6 wt. % of minerals and / or fillers and / or pigments and water, and 0.5 wt. %, respectively. 1.2 wt. %, respectively. 0.4 wt. % amphoteric, against the exterior neutral polyelectrolytes with a viscosity of 37 mPa.s at a solids content of 72 wt. %, respectively. 67 wt. % based on dry mineral, respectively. dry filler, resp. dry piment, such granulometry that 70 wt. %, respectively. 90 wt. %, respectively. 60 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm.

It is further preferred that the aqueous suspension consists of 97 to 99.89 wt. %, preferably 98.5 to 99.8 wt. %, preferably 99.2 to 99.65 wt. % of minerals and / or fillers and / or pigments and water, and from a mixture of dispersing agents of amphoteric cationic and amphoteric slightly anionic and / or amphoteric and / or amphoteric slightly cationic polyelectrolytes in the range of 0.11 to 3.00 wt. %, preferably 0.2 to 1.5 wt. %, preferably 0.35 to 0.8 wt. %, based on a solids content in the range of 60 to 80 wt. %, preferably 62 to 75 wt. %, in particular 65 to 72 wt. % based on dry mineral, respectively. dry filler, resp. dry pigment.

Excellent results are obtained when the aqueous suspension consists of 99.6 wt. % of minerals and / or fillers and / or pigments and water, and 0.4 wt. % of the aforesaid dispersing composition according to the invention.

Particularly good results are obtained when the aqueous suspension consists of 99.6 wt. % of minerals and / or fillers and / or pigments and water, and 0.4 wt. % of a mixed dispersant consisting of 0.35 wt. % of amphoteric cationic polyelectrolytes of the formula shown on page 30, where a = 95 mol% and b = 5 mol% and c = 0 mol%, at a viscosity limit of 27.3 ml / g and 0.1 wt. % of amphoteric polyelectrolytes of the general formula given on page 30, where a = 50 mol% and b = 50 mol% and c = 0 mol%, with a viscosity measured in 32% aqueous solution, 37 mPa · s, with a solids content of 67 wt. %, wherein 60 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm.

-24GB 286834 B6

It is a further object of the present invention to provide a process by which a highly concentrated and storage-stable suspension of minerals and / or fillers and / or pigments can be produced by milling at a high solids content, milling and dispersion being carried out in a single operation.

This object was achieved according to the invention by preparing a process for the preparation of aqueous suspensions which is characterized by the following process steps:

(a) the aqueous suspension of minerals and / or fillers and / or pigments is wetted together with the dispersing and grinding aid of the invention, wherein:

(b) amphoteric polyelectrolytes of the invention are added either all prior to grinding or

(c) a portion of the amphoteric polyelectrolytes of the invention is added prior to milling; and

(d) a portion of the amphoteric polyelectrolytes is added during grinding and / or

(e) a portion of the amphoteric polyelectrolytes is added after grinding.

Particularly preferred is the method in which they are added

(a) amphoteric, slightly anionic and / or amphoteric polyelectrolytes, all prior to milling; or

(b) part of the amphoteric, slightly anionic and / or amphoteric polyelectrolytes is added before grinding; and

(c) part of the amphoteric, slightly anionic and / or amphoteric polyelectrolytes are added during milling and / or

(d) a portion of the amphoteric, slightly anionic and / or amphoteric polyelectrolytes is added after grinding.

Further, a method in which

(a) amphoteric and / or amphoteric cationic polyelectrolytes are added before milling; or

(b) part of the amphoteric and / or amphoteric cationic polyelectrolytes is added prior to milling; and

(c) part of the amphoteric and / or amphoteric cationic polyelectrolytes is added during milling and / or

d) a portion of the amphoteric and / or amphoteric cationic polyelectrolytes is added after grinding.

Particularly preferred is the process in which it is added

a) 50 to 100 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes prior to grinding, and

b) 0 to 50 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes during grinding and / or

c) 0 to 50 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes after grinding.

-25GB 286834 B6

Further, the process in which it is added is preferred

a) 50 to 100 wt. % amphoteric and / or amphoteric cationic polyelectrolytes prior to milling; and

b) 0 to 50 wt. % amphoteric and / or amphoteric cationic polyelectrolytes during grinding and / or

c) 0 to 50 wt. % amphoteric and / or amphoteric cationic polyelectrolytes after grinding.

Very good results are obtained when the procedure in which they are added is used

a) 70 to 100 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes prior to milling and / or

b) 0 to 30 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes during grinding and / or

c) 0 to 30 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes after grinding.

Further, the process in which it is added is preferred

a) 70 to 100 wt. % amphoteric and / or amphoteric cationic polyelectrolytes prior to milling; and

b) 0 to 30 wt. % amphoteric and / or amphoteric cationic polyelectrolytes during grinding and / or

c) 0 to 30 wt. % amphoteric and / or amphoteric cationic polyelectrolytes after grinding.

Further, the process in which it is added is preferred

(a) a part of amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolytes prior to milling, and / or

(b) a part of amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolytes during grinding and / or

(c) a portion of amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolytes after grinding.

Further, the process in which it is added is preferred

(a) amphoteric cationic polyelectrolytes prior to milling; or

(b) a portion of the amphoteric cationic polyelectrolytes is added during milling and / or

(c) a portion of the amphoteric cationic polyelectrolytes is added after grinding.

-26EN 286834 B6

Particularly preferred is the addition process

a) 10 to 90 wt. %, respectively. 20 to 40 wt. %, respectively. 30 wt. % amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolyte prior to milling and / or

b) 10 to 90 wt. %, respectively. 60 to 80 wt. %, respectively. 70 wt. % amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolyte during grinding and / or

c) 0 to 80 wt. %, respectively. 0 to 20 wt. % amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolytes after grinding.

Particular preference is given to the addition process

a) 50 to 100 wt. %, respectively. 70 to 100 wt. % amphoteric cationic polyelectrolytes prior to milling and / or

b) 0 to 50 wt. %, respectively. 0 to 30 wt. % amphoteric cationic polyelectrolytes during grinding and / or

c) 0 to 50 wt. %, respectively. 0 to 30 wt. % amphoteric cationic polyelectrolytes after grinding.

If the desired final fineness in the grinding sink is to be achieved, excellent results are obtained by adding 100 wt. % amphoteric, slightly anionic and / or amphoteric polyelectrolytes or 100 wt. % amphoteric, and / or amphoteric cationic polyelectrolytes prior to grinding.

With multiple milling sinks to achieve final fineness, excellent results are obtained when the corresponding amount of dispersant is distributed appropriately with the fineness achieved during grinding.

According to the invention, aqueous suspensions of minerals and / or fillers and / or pigments find use in the manufacture of papimas and / or papimus. in paper processing. Other applications are found in the surface treatment (pigmentation) of papim surfaces in a size press of a papermaking machine, in papim coatings, in a primer or in a primer. in topcoat, in wood to combat interfering substances (control of pitch), in circulating water of paper machines to reduce CSB (reduction of oxygen consumption), in wastewater treatment plants, to flocculate anionically stabilized pigment and / or mineral suspensions and / or fillers in the paper industry, or for flocculation (immobilization) of paints in smoothings.

According to the invention, a high solids content of> 60 wt. % prepared by grinding a suspension of minerals and / or fillers and / or pigments which appear to be both electrostatically positive and sterically stable and the suspension remains sufficiently viscous stable for weeks, very well transportable over long routes, does not settle (not sediment), and eg retention in paper production excellent.

Surprisingly and unpredictable was the fact that, with a suitable combination of one or more cationic monomers and one or more anionic monomers, as well as suitable additives, amphoteric polyelectrolytes polymerized before and / or during and / or after the milling process at high shear forces and temperatures occur during wet grinding, none occurs

Neutralizing counter-charged monomer units and thereby coagulating the polymer. In contrast, optimum grinding and slurry stabilization over a long period of time are achieved.

The zeta potentials of the filler and / or pigment and / or mineral particles exhibit a positive precursor or are neutral to the exterior, i.e., for the neutral filler and / or pigment and / or mineral particles, the total number of positive and negative charges on the particle surfaces varies with each other.

Good storage stability in relation to viscosity and settling properties is of decisive importance especially during transport and in large storage tanks, as it prevents the destruction of goods. In the case of the mineral and / or filler and / or pigment suspension prepared according to the invention, the place of production of the suspension as well as the place of consumption (eg paper mill) can be freely selected. Thus, the site of production can adapt to the geological site of minerals and / or fillers and / or pigments and does not have to take account of the location of the customers from purely logical plans. That is why the choice of the transport vehicle is absolutely free and an environmentally thought-out variant can be chosen.

Aqueous suspension of minerals and / or fillers and / or pigments, with a solids content of> 60 wt. %, based on dry minerals and / or fillers and / or pigments, are prepared according to the invention by grinding the coarse crushed raw materials, wherein the amphoteric polyelectrolytes of the invention are added at the beginning of grinding and / or another part of the amphoteric polyelectrolytes in the composition according to the invention to reduce the viscosity.

These mineral and / or filler suspensions and / or pigments, ideally granular, concentrated and stable when stored at low viscosity, can be prepared by the process of the invention in a single step, which represents enormous economic and qualitative progress for users, especially the paper industry.

Preferably, the concentration of the aqueous suspensions is 60 to 78% by weight. %, based on dry mineral.

Preferably, the feedstock has a mean equivalent spherical particle diameter of 10 to 50 µm (measured on a Sedigraph 5100) prior to the grinding process according to the invention.

Example notes:

(a) Viscosity measurement of amphoteric polyelectrolytes

Viscosity measurements were performed on a Brookfield viscometer of the PVF-100 type at 100 rpm. Density meter 1 was used for each measurement:

the concentration was 32 wt. % polymer in water. The pH at which the viscosity was measured corresponds to that given in the corresponding examples. Anionic groups are reported non-neutralized.

The measurement was performed in a 400 ml beaker of low shape. The temperature during the measurement was 20 ° C, the measurement was carried out after stirring for 1 min.

This kind of viscosity measurement was used for all of the following examples, with the exception of amphoteric cationic polyelectrolytes mixed with amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolytes.

b) Fineness of the mineral and / or filler and / or pigment suspension

The fineness of the suspension produced according to the invention was determined by gravity field sedimentation analysis on a Sedigraf 5100 from Micromeritics USA.

-28GB 286834 B6

Measurements of cationically stabilized suspensions were performed in distilled water. The test samples were dispersed by means of a high speed stirrer and ultrasound. Dust measurements were performed in 0.1% Na4P2C solution> 7.

The measured particle distribution was shown on the XY recorder as a waveform of the sum curve (see, e.g., Belger, P. Swiss Association of Medical and Dyeing Chemists, XVII. FATIPEC Congress, Lugano, September 23-28, 1984), where it is plotted on an axis. X is the diameter of the particles of one corresponding spherical diameter, and on the Y-axis the proportion of particles in mass. %.

c) Measuring the viscosity of the mineral and / or filler and / or pigment suspension

Viscosity measurements were performed on a Brookfield viscometer type PVF-100 at 100 rpm. The following hydrometers were used for each measurement:

Hydrometer

RH 2 40-320 mPa.s

RH 3 320-800 mPa.s

RV 4800-1600 mPa.s

RV 5 1600-3200 mPa.s.

RV 6 3200-8000 mPa.s

The measurement was performed in a 400 ml beaker of low shape. Temperature during reagent measurement 20 ° C. The measurement was performed after 1 min stirring time. Prior to each measurement, all test specimens were vigorously stirred for 2 min (5000 rpm, 50 mm disc mixer diameter). This kind of viscosity measurement was used for all the following examples.

(d) The specific viscosity, having the Greek letter 'Eta', for the anionic dispersant in the examples used, was determined as follows:

A polymer / copolymer solution was prepared to measure 100% neutralized with sodium hydroxide (pH 9) by dissolving 50 g, based on dry polymer / copolymer, in 1 L of distilled water containing 60 g NaCl.

Then, a capillary viscometer with a Baume constant of 0.000105, in a 25 ° C thermally stabilized heating bath, is measured, the time it takes a precisely defined volume of alkaline polymer / copolymer solution to flow through the capillary, and compared to the time it takes the same volume of control solution at 60 ° C. g NaCl / 1 to flow through the capillary.

It is therefore possible to define the specific viscosity "Eta" as follows:

flow time flow time polymer solution - NaCl solution

Eta = ---------------------------------- Flow time of NaCl solution

Better results are obtained when the capillary diameter is selected such that the time required for the polymer / copolymer containing NaCl solution is between 90 and 100 sec.

e) The limit viscosity of amphoteric cationic polyelectrolytes in admixture with amphoteric, slightly cationic and / or amphoteric and / or amphoteric, slightly anionic polyelectrolytes, such as the Poly-DADMAC of Examples 1 a) to 1 c), was determined according to the following literature:

B. Vollmert "Grundriss der Makromolekularen Chemie" vol. III

E. Vollmert-Verlag, Karlsruhe 1985.

-29EN 286834 B6

f) Measurement of charge of suspension of pigments, fillers and minerals and SCD

The determination of surface charges was performed by Streaming Current Detector from Mustek, Hersching b. Munchen (Type PCD-02).

The titrations were carried out according to the embodiment of the dissertation of Peter Hess "Untersuchungen zur Anwendung der Polyelektrolyttitration auf dem Gebiet der Papierherstellung", Darmstadt, 1983, in particular according to page 33 ff of this dissertation. 0.01 M potassium polyvinyl sulphate (KPVS) fa was used as the titration solution. SERVA.

Examples

I. Examples of the prior art

Example 1a mass. % aqueous slurry of natural marble with a particle size such that 60 wt. % of the particles exhibited an equivalent spherical diameter <2 µm (measured on Sedigraph 5100), dispersed with 0.1 wt. % poly (diallyldimethylammonium chloride), a viscosity limit of 25 ml / g, and 0.02 wt. % of sodium polyacrylate (spec, viscosity 0.35; 100% carboxyl groups neutralized with sodium hydroxide), all based on dry marble, (8000 rpm, 50 mm disc mixer diameter).

Viscosity in mPa.s after 1 h 2 days 6 days 12 days

204 420 640 1560

Example 1a (according to the prior art) shows that the viscosity is not stable and the suspension becomes unnecessary after two weeks.

Example 1b

It was attempted to grind 67 wt.% Aqueous slurry of natural marble with a mean equivalent spherical particle diameter of 12 µm (measured on a Sedigraph 5100) according to the following Dynomill (0.61 grinding container) using glass grinding bodies (0 mm), to a grain size curve such that 60 wt. % of the particles showed a mean equivalent spherical particle diameter of <2 µm / (measured on a Sedigraph 5100).

Regulation:

5000 g marble g poly (diallyldimethylammonium chloride) viscosity limit 25 ml / g

4.5 g of sodium polyacrylate (spec, viscosity 0.35; 100% carboxyl groups neutralized with NaOH)

2472 g of water

The grinding had to be interrupted because the viscosity increase was so high that further grinding was no longer possible as the mill was blocked. The required fineness could not be achieved.

-30GB 286834 B6

Example 1c by weight, a% aqueous slurry of natural marble with an average equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground on Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm ) to a grain size curve such that 60 wt. % of the particles showed a mean equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g marble g poly (diallyldimethylammonium chloride) viscosity limit 25 ml / g

4.5 g of sodium polyacrylate (spec, viscosity 0.35; 100% carboxyl groups neutralized with NaOH)

3346 g of water

Also at a concentration of 60 wt. %, no improvement in the grinding properties with poly (diallyldimethylammonium chloride) compared to experiment 1b was achieved.

Grinding to the desired fineness at viscosities < 2000 mPa.s was not possible by the prior art method.

II. Examples according to the invention

Example 2

A 67 wt.% Aqueous slurry of natural marble was prepared with a grain size of 60 wt. % of the particles exhibit an equivalent spherical diameter <2pm (measured on Sedigraph 5100) with varying amounts, based on dry marble, of the following copolymers,

a = 50 mole% b - 50 mole% /

wherein the copolymer is additionally of molecular weight and / or molecular weight. intrinsic viscosity 32 wt. % aqueous solution was changed. Disperse with a strong stirrer (8000 rpm, disc diameter 50 mm). The aim of this test series was to determine the optimum viscosity, respectively. the molecular weight of the amphoteric polyelectrolytes as well as the optimum amount of dispersant.

-31GB 286834 B6

Table 1

viscosity and pH of amphoteric polyelectrolytes (32 wt.% in H ₂ O) amount of addition in wt. % based on dry marble suspension viscosity viscosity PH instantaneous after 20 days 95 mPa.s 3.3 0.1 1440 0.15 840 0.2 610 0.25 420 0.3 340 0.35 275 0.4 215 0.5 165 155 61 mPa.s 3.3 0.1 1430 0.2 420 0.3 265 0.4 190 180 37 mPa.s 3.3 0.1 950 0.2 250 0.3 145 230 24 mPa.s 3.5 0.1 1910 0.2 1180 0.3 670 0.4 455 0.5 360 0.6 275 0.7 200 280

The optimum viscosity of the amphoteric polyelectrolytes is between 30 and 50 mPa · s

Example 3

A 67 wt.% Aqueous slurry of natural marble was produced in such a granularity that 60 wt. % of the particles exhibited an equivalent spherical diameter of <2 µm (measured on Sedigraph 5100), with varying amounts, based on dry marble, of the following copolymer

-32GB 286834 B6

a = 70 mol% b = 30 mol%, wherein the copolymer is additionally varied in molecular weight and / or molecular weight. an intrinsic viscosity of 32 wt.% aqueous solution. It is dispersed with a strong stirrer (8000 rpm, diameter of a disc mixer 50 mm).

The aim of this test series was to determine the optimum viscosity event. the molecular weight of the amphoteric cationic polyelectrolytes, as well as the optimum amount of dispersant.

Table 2

viscosity and pH amount amphoteric cationic allowance v viscosity polyelectrolytes wt. % suspension (32 wt.% In H ₂ O) relative to dry marble viscosity PH instantaneous after 10 days 106 mPa.s 3.7 0.1 465 0.2 260 0.3 200 345 44 mPa.s 3.7 0.1 535 0.2 220 0.3 140 375 33 mPa.s 3.7 0.1 1090 0.2 750 0.3 570 0.4 430 0.5 290 0.6 200 530

Example 4

A 67 wt.% Aqueous slurry of natural marble was made in such a granularity that 60 wt. % of the particles exhibited an equivalent spherical diameter of <2 µm (measured on Sedigraph 5100), with varying amounts, based on dry marble, of the following copolymer

-33GB 286834 B6

a = 47 mole% b = 53 mole%, wherein the copolymer is additionally varied in molecular weight and m.p. intrinsic viscosity 32 wt. % aqueous solution. It is dispersed with a strong stirrer (8000 rpm, diameter of a disc mixer 50 mm).

The aim of this test series was to determine the optimum viscosity event. the molecular weight of the amphoteric slightly anionic polyelectrolytes, as well as the optimum amount of dispersant.

Table 3

viscosity and pH amount slightly anionic amphoteric allowance v viscosity polyelectrolytes wt. % suspension (32 wt.% In H ₂ O) relative to dry marble viscosity PH instantaneous after 10 days 84 mPa.s 3.1 0.1 1500 0.2 840 0.3 420 0.4 275 0.5 185 165 40 mPa.s 3.0 0.1 1180 0.2 265 0.3 165 190

Example 5% by weight aqueous slurry of natural marble with an average equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) per particle size curve such that 70 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

-34GB 286834 B6

Regulation:

5000 g marble g amphoteric copolymer corresponding to the formula in Example 2 (viscosity 37 mPa.s)

1925 g water

Viscosity: after 2 hours 1 day 5 days 6 days 16 days 30 days [mPa.s] 215 255 300 365 430 515

Surface charge after 7 days +7.9 pVal / g solid.

In Example 5, it is clearly shown that a fine-grain suspension of minerals and / or fillers and / or pigments having a very low and stable viscosity at high concentrations for weeks is prepared in the batch of amphoteric polyelectrolytes of the invention and also by grinding.

Example 6% by weight of an aqueous suspension of "Champagne" chalk with an average equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) to a grain size curve such that 90 wt. % of the particles showed a mean equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g chalk "Champagne" g amphoteric copolymer corresponding to the formula in Example 2 (viscosity 37 mPa.s)

1715 g water

Viscosity: after 1 h 1 day 10 days 20 days [mPa.s] 600 650 710 900

Example 7% by weight of an aqueous slurry of natural marble with a mean equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) per particle size curve such that 90 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g marble g of amphoteric polymer of Example 2 1418 g of water

Viscosity: after 1 hour 1 days 10 days 20 days [mPa.s] 740 780 870 980

-35GB 286834 B6

Surface charge after 7 days +10.1 pVal / g solid.

Example 7a

On a pilot scale, the marble used in Example 7 was ground in a vertically arranged bead mill (Sussmeier containing 180 liters) with glass grinding bodies (0-2 mm) to a grain size curve such that 90 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on Sedigraph 5100) at a concentration of 74.5 wt. %. They were made approx. 2t of this suspension.

Regulation:

1480 kg of marble

10.4 kg of the amphoteric polymer of Example 2

510 kg of water to add

Viscosity: after 1 h 1 day 10 days 20 days [mPa.s] 600 560 680

Surface charge after 7 days +11.9 pVal / g solid.

Examples 6 and 7 and 7a show that the very high finenesses found in coating formulations can be prepared at high concentration without problems by grinding coarse crushed raw stones (raw materials).

Example 8% by weight of an aqueous slurry of natural marble with an average equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) to a grain size curve such that 60 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g of marble g of amphoteric copolymers corresponding to the formula of Example 2 (viscosity 37 mPa.s)

2472 g water add

Viscosity: after 2 hours 1 day 5 days 8 days 16 days 30 days [mPa.s] 120 130 140 212 208 520

Surface charge after 7 days +4.8 pVal / g solid.

In Example 8, it is clearly seen that in a batch of amphotemes against the exterior neutral polyelectrolytes of the invention, as well as by grinding, a fine-grained suspension of minerals and / or fillers and / or pigments is obtained. It can be used as a filler in the paper industry.

-36GB 286834 B6

EXAMPLE 9 A 9% by weight aqueous slurry of natural marble with an average equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground in Dynomill (0.61 grinding container) using glass grinding bodies (0 mm). a grain size curve such that 60 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g of marble g of the amphoteric polymer of Example 5, wherein ua) was 95 wt. % of carboxyl groups neutralized with Ca (OH) ₂ aub) 95 mol% neutralized with Mg (OH) ₂ (viscosity 37 mPa.s)

2460 g water add Viscosity: after 1 hour 1 days 4 days 8 days 16 days [mPa.s] a) 96 110 130 140 160 (b) 104 155

Example 9 shows that the neutralization of carboxyl groups with calcium and / or magnesium in the amphoteric polyelectrolytes of the invention, despite the very high solids content and only slightly more dispersant, results in better viscosity compared to Example 8 than the same non-neutralized amphoteric polyelectrolyte.

Example 10% by weight aqueous slurry of natural marble with an average equivalent spherical particle diameter of 12 µm (measured on Sedigraph 5100) according to the following formula was ground in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) to a grain size curve such that 60 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g marble

17.5 g of an amphoteric cationic copolymer of the following formula

-37GB 286834 B6

a = 95 mol% b = 5 mol% viscosity limit 27.3 ml / g

2.5 g of amphoteric copolymers in which the anionic and cationic groups are in a ratio of 1: 1 analogously to Example 2 with a viscosity of 37 mPa.s added before milling

2.5 g As the first 2.5 g, 2472 g of water are added during grinding

Viscosity: after 2 hours 1 day 4 days 8 days 16 days 30 days

450 cP 450 cP 520 cP 615 cP 730 cP 830 cP

Example 10 shows that with the combination of amphoteric polyelectrolytes of the invention found, it is possible to obtain a transportable non-sedimenting suspension of calcium carbonate by grinding the count of crushed stone. Viscosity at high concentration is good.

These marble suspensions made according to Examples 5 and 8 were investigated, in comparison with one, today commonly used with an anionic dispersing agent consisting of a marble suspension, for their retention in paper making.

Test conditions:

Substance: 80% birch sulphate degree of grinding 23 ° SR% pine sulphate

Retention aid: 0.05% polyacrylamide (viscosity limit 700 ml / g)

Conducting a retention test according to Britt-Jar (a), by Piper Research Material, SYRACUSE, USA:

1. Into a Britt-Jar container, place 275 ml of a 2% fibrous suspension (3.63 g of absolutely dry fibers) together with 275 ml of distilled water.

2. Britt-Jar (ovo) stirrer at 700 rpm

3. Add 25.4 ml of a 5% suspension of minerals and / or fillers and / or pigments

4. Add the appropriate amount of retention agent after 20 s

-38GB 286834 B6

5. After 25 seconds, open the drain cock and allow 100 ml of sieve water to drain.

6. Determine the proportion of CaCo ₃ in the sieve water complexometrically after decomposition with HCl or by annealing - AAS. For other minerals and / or fillers and / or pigments, the sieve water is filtered through a membrane filter, burnt to ashes at 600 ° C by alkaline thermal decomposition, eg with NaOH,

KOH in a zirconium crucible, converted to the anhydrous form and determined in acidified state by AAS. The content of the minerals and / or fillers and / or pigments may be determined with respect to the respective conversion factors.

7. The retention of the filler can be calculated from the clogged fraction of minerals and / or fillers and / or pigments per 100 ml and from the sieve water determined fraction of minerals and / or fillers and / or piments per 100 ml.

Results:

Products: filler retention at first application anionically stabilized CaCO ₃ suspension with 60% <2pm (0.15% natriumpolyacrylate spec, viscosity 0.35) anionically stabilized CaCO ₃ suspension with 70% <2pm (0.3% natriumpolyacrylate spec, viscosity 0.54) CaCO ₃ suspension of Example 8 CaCO ₃ suspension of Example 5 41.1% 35.3% 62.4% 65.8%

By utilizing the marble suspension produced by the process of the invention, it is possible to increase the retention of the filler without negatively limiting the formation and strength of the paper, which represents an enormous development leap.

The aqueous suspensions according to the invention, as well as the process for their preparation, have, inter alia, the following advantages:

in contrast to known processes, a highly concentrated (> 60 wt.%) suspension of minerals and / or fillers and / or pigments can be prepared by wet grinding of coarsely crushed raw materials.

- it is possible to increase the filling capacity of the paper without significant loss of strength in the market, resulting in an enormous economic profit in the production of paper. Furthermore, it has been shown with the composition according to the invention that it is possible to increase the filling level from 15 wt. % to 17 wt. % without significant loss of paper strength, especially market strength.

New practical tests have shown that increasing the filling from 16 wt. % to 26 wt. % is achievable without adversely affecting the paper properties.

suspensions exhibit excellent storage stability at low viscosities without sedimentation problems

when used in paper production, for example, great advantages are achieved with respect to filler retention

- grinding and dispersion is possible at high grinding forces and boiling point of water

-39GB 286834 B6

- environmentally friendly transport options can be chosen.

A particular embodiment of the invention is characterized in that the dispersant is a mixture of one or more cationic polyelectrolytes and / or one or more amphoteric cationic polyelectrolytes in which the non-neutral monomer units carry predominantly positive charges and one or more partially neutralized anionic polyelectrolytes and / or one or more partially neutralized amphoteric anionic polyelectrolytes in which the non-neutral monomer units carry predominantly negative charges.

In the following, the partially neutralized anionic, respectively. cationic polyelectrolytes and partially neutralized amphoteric anionic, respectively. cationic polyelectrolytes briefly referred to as the inventive anionic, respectively. inventive cationic polyelectrolytes.

Preferably, the dispersing agent is a mixture of one or more homopolymic cationic polyelectrolytes and / or one or more copolymeric amphoteric cationic polyelectrolytes in which the non-neutral monomer units bear predominantly positive charges and one or more homo- and / or copolymically partially neutralized anionic polyelectrolytes and / or one or more more amphoteric anionic partially neutralized polyelectrolytes in which the non-neutral monomeric units carry predominantly negative charges.

Preferably, the cationic polyelectrolyte and / or the amphoteric cationic polyelectrolyte, in which the non-neutral monomer units carry predominantly positive charges, have a positive charge functional group in the ethylene backbone substituent.

It is further preferred that the substituent is linked to the backbone by groups

OH O

II I II

-C-N or -C-O ^-.

It is further preferred that the cationic polyelectrolyte comprises quaternary ammonium groups and that the amphoteric cationic polyelectrolyte in which the non-neutral monomer units carry predominantly positive charges comprises quaternary ammonium groups and carboxyl groups and / or sulfo groups and / or acid groups of phosphoric acid esters.

It is particularly preferred that the cationic polyelectrolyte is one or more of the following compounds of the formula

I ^{5 R} 1 1 | T 1 ^R 6 1 c = o AND 1 X AND 1 Y | r ₂ - -n ⁺ -r ₄ r ₃ n

(An) ’

Wherein R 1, R _5a = H

and / or R ₂ to R ₆

alkyl and / or

-aryl, wherein R 5 may also be

AND

C = O x

I γ l ₊ r _{2 -} n ^{+ -} r ₄

I ^R 3

X = O and / or N-H

Y = -CH ₂ - to -C 5 H ₁₀ - n = 20 to 3000 and (An) 'may be chloride and / or bromide and / or iodide and / or HSO ₄ ^- and / or CH ₃ SO ₄ ' and / or nitrite.

It is particularly preferred that in this formula it is meant

R 1 = H or -CH ₃

R ₂ ⁼ —CH ₃ or —C ₂ H 5

R ₃ ⁼ —CH ₃ or —C ₂ H 5

R 4 = CH ₃ to -C 4 H 9 and isomers

X = O or N-H

Y = -CH ₂ -to-C ₅ H _{1 (r} -

R 5 and R 6 = H, especially when Y = - (CH ₂ ) ₃ - a

X = -NH.

A preferred amphoteric cationic polyelectrolyte in which the non-neutral monomeric units carry predominantly positive charges is one or more of a group corresponding to the following general formula

-41GB 286834 B6

wherein R 1, R ₅ , R 6 and R ₇ = H

- and / or R 1 to R ₇

- alkyl and / or -aryl, wherein R ₅ may also be

C = O

AND

X

AND

Y 1 ₊ r ₂ -n ⁺ -r ₄

Rg and _R9 can be

- H and / or

alkyl and / or

-aryl,

R 8 or R ₉ may also be O

II

-COH when

O

II

Z is -COH,

-42EN 286834 B6

-X = O and / or N-H,

Y = -CH ₂ - to -C5H10-,

-Z = -COH and / or

- (CH ₂ ) _n -COH and / or

O

II

- (CH ₂ ) _n -S = O and / or

AND

OH

O

II

S = O and / or

OH acidic phosphoric acid ester residue aa = 70-99 mol% b = 1-30mol% n = 1-18 and (A _n ) * can be chloride and / or bromide and / or iodide and / or HSO4 * and / or CH3SO4 and / or nitrite

It is particularly preferred that the amphoteric cationic polyelectrolyte is a compound of the formula wherein:

R 1 = H or -CH ₃

R ₂ - —CH 3 or —C ₂ H 5

R 3 - —CH 3 or —C ₂ H ₅

R 4 = -CH ₃ to -C 4 H 9 and isomers

X = O or N-H

Y = -CH ₂ -to-C ₅ H ₁₀ R, and R $ = H,

R ₇ = H or -CH 3

R ₉ and R ₉ ⁼ H.

-43GB 286834 B6

Very particularly advantageous if (An) is Cl and Y is - (CH _{2) 3} -.

It is further preferred that the anionic partially neutralized polyelectrolyte is one or more of the group represented by the following general formula:

-Z = -COHor

O

II

- _(CH2) n-COH, and / or

O

II

- (CH ₂ ) _n -S = O and / or

OH

acidic phosphoric acid ester residue

R 1 = -H or -CH ₃

R ₂ and R ₃ = H and / or

-alkyl and / or aryl, where R ₂ or R ₃ may also represent Z,

O

II when Z = -C-OH = +1 and / or +11 and / or + III

Ca = alkali metal, alkaline earth metal, alkaline earth metal cation w = 59 to 95 mol% to the amount of Z in the monomer v = 5 to 41 mol% divided by n = 1-12.

-44EN 286834 B6

It is further preferred that the partially neutralized anionic polyelectrolyte is a mixture of one or more homo- and / or copolymers of compounds corresponding to this general formula.

Furthermore, it is preferred that the amphoteric anionic partially neutralized polyelectrolyte in which the non-neutral monomeric units bear predominantly negative charges is one or more of a group of compounds corresponding to the general formula

Re Ri 1 1 Ro R7 1 1 1 1 1 1  C C | AND C. Lr [| 1 1 R 2 - C = O ⁶ 1 X 1 1 1 r ₉ z b 1 Y | <An) ^r 2 - ⁺ - ^r 4 1 -What? _______________1 and

wherein R 1, R 5, R ₆ and R ₇ = H

- and / or R 1 to R 2?

- alkyl and / or -aryl, wherein R ₅ may also be

C = O

AND

X

AND

Y 1 ₊ r ₂ -n ⁺ -r ₄

R 8 and R ₉ may be

- H and / or

alkyl and / or

- aryl

R 8 or R ₉ may also be

II

-COH,

-45GB 286834 B6 when O

II

Z is COH,

-X = O and / or NH ₂ -Y-CH - to -C5H10-,

O

II

-Z may be -COH and / or

O

II

- (CH ₂ ) _n -COH and / or

O

II

- <CH ₂ ) _n -S = O and / or

OH

acidic phosphoric acid ester residue aa = 1-30 mol% b = 70 - 99 mol% n = 1-18 and (A _n ) - can be chloride and / or bromide and / or iodide and / or HSO ₄ and / or CH ₃ SO ₄ and / or nitrite.

It is particularly preferred that the amphoteric anionic partially neutralized polyelectrolyte is one or more compounds corresponding to this general formula wherein:

R 1 = H or -CH ₃

R ₂ ⁼ —CH ₃ or —C ₂ H 5

R ~ ₃ -CH ₃ or -C ₂ Hs

R 4 = -CH ₃ and -C ₄ H _9, and isomers thereof

X = One or N-H

Y-CH ₂ C ₅ -to-HioR5 and R $ = H,

-46GB 286834 B6

R ₇ = H or -CH ₃

R ₉ and R ₉ = H.

It is particularly preferred that (An) 'is Cl and

Y = - (CH ₂ ) ₃ -.

Another advantageous embodiment of the invention is that the anionic partially neutralized polyelectrolyte is a homo and / or copolymer, and that the amphoteric anionic partially neutralized polyelectrolyte in which the non-neutral monomer units bear predominantly negative charges is a partially neutralized anionic polyelectrolyte containing carboxyl groups and / or sulfo groups. and / or acid phosphoric acid ester residues.

It is particularly favorable that the partially neutralized anionic polyelectrolyte is a partially neutralized polyacrylic acid and / or a partially neutralized polymethacrylic acid and / or a partially neutralized copolymer thereof.

Preferably, in the anionic partially neutralized polyelectrolyte and in the amphoteric anionic partially neutralized polyelectrolyte, only a statistical proportion of the acid groups is mono- and / or polyvalent cation.

Alkali and / or alkaline earth and / or alkaline earth and / or amines and / or alkanolamines and / or quaternary ammonium cations are preferably used as cations, with Na ⁺ and / or K ⁺ and / or especially being used as cations or Li ⁺ and / or NH ₄ ⁺ and / or Ca ²⁺ and / or Mg ²⁺ and / or Sr ²⁺ . Particularly good results are obtained when cations of alkali metal and / or alkaline earth metal cations, in particular alkali metal cations and here in particular Na ⁺ , are used as cations. NH / is unsuitable as it causes a strong odor load and leads to health damage.

The dispersing agents which are particularly suitable according to the invention are mixtures corresponding to the general formulas of point 14 and / or amphoteric cationic polyelectrolytes of points 15 and 16 and / or amphoteric anionic partially neutralized polyelectrolytes of point 15.

Particularly preferred is a mixed dispersant according to the following general formula

-47GB 286834 B6 z (cat) ⁺

where (Kat) ⁺ - Cations of alkali metals and / or alkaline earths and / or alkaline earth metals and / or amines and / or alkanolamines and / or quaternary ammonium cations (A _n ) '= chloride, bromide, iodide, HSO4', CH3SO4 ^- and / or nitrite and a = 60 to 99 mol%, b = 1-40 mol%, z = 1-70 mole% n = 30-99 mole%.

Particularly preferred are the mixed dispersants according to the general formula wherein (KAT) ⁺ = alkali metal and / or alkaline earth cations (A ')' = chloride, bromide, iodide, HSOf, CH 3 SO 4 'and / or nitrite and = 80-98 mol% b = 2-20 mol% z = 2-50 mol% w = 50-98 mol%.

Further preferred are mixed dispersants according to the general formula wherein (KAT) ⁺ = Na ⁺ , K ⁺ , Li ⁺ , Ca ²⁺ , Mg ²⁺ and / or S ²⁺ ; ⁺ (A _n ) '= chloride, bromide, iodide, HSO ₄ ', CH3SO4 'and / or nitrite a = 85-97 mol% b = 3-15 mol% z = 3-30 mol% w = 70 - 97 mol %.

Extremely favorable results are obtained when the dispersing blend is a blend according to the general formula wherein (K a) ⁺ = alkali metal ion (A _n ) '= halide ion a = 90-96 mol% b = 4-10 mol%

Z = 4-20 mol% w = 80-96 mol%.

Excellent results are obtained when the dispersing blend is a composition according to the general formula wherein (K a) ⁺ = Na ⁺ (A yy = cr a = 95 mol% b = 5 mol% z = 5 mol% w = 95 mol% .

Preferably, the anionic polyelectrolyte and / or the amphoteric anionic polyelectrolyte are partially neutralized with alkali metal and / or alkaline earth cations and / or alkaline earth metal cations and / or amines and / or alkanolamines and / or quaternary ammonium cations, particularly suitable alkali metal cations and / or or alkaline earths, very particularly alkali metal cations and here in particular the Na ⁺ cation.

In anionic polyelectrolytes and / or amphoteric anionic polyelectrolytes, 1 to 70 mol% of acid groups are favorably neutralized. Particularly favorable results are obtained when 2 to 60 mol%, in particular 3 to 30 mol% of the acid groups are neutralized, with a neutralization step of from 5 mol% to 10 mol% giving the best results.

Non-neutralized polyacrylic acid is unsuitable as it starts to crystallize at 20 ° C and is therefore no longer dispensable. Once crystallization has occurred, the polymer solution must be heated to 100 ° C to dissolve the crystals again. In winter and in colder regions, production with non-neutralized polyacrylic acids is impossible.

It is preferred that the specific viscosity of the "Eta" of the partially neutralized anionic polyelectrolyte and / or the amphoteric anionic polyelectrolyte in admixture with the cationic and / or amphoteric cationic polyelectrolyte, calculated as complete salt, is between 0.2 and 1.0. It is particularly preferred that the "Eta" is between 0.35 and 0.6 and is extremely favorable when the "Eta" is 0.55.

It is preferred that the polymerization degree of cationic polyelectrolytes and / or amphoteric cationic polyelectrolytes in a mixture with a partially neutralized anionic polyelectrolyte, based on the cut-off viscosity, be in the range of 5 ml / g to 50 ml / g. A polymerization step in the range of 15 ml / g to 40 ml / g is particularly preferred, with a range of 25 ml / g to 35 ml / g being particularly preferred.

Preferably, the dispersing blend comprises up to 98 wt. % of cationic polyelectrolytes and / or amphoteric cationic polyelectrolytes and up to 30 wt. % of anionic partially neutralized polyelectrolytes and / or amphoteric partially neutralized anionic polyelectrolytes.

Further preferably, a dispersing blend of up to 95 wt. % of cationic polyelectrolytes of the invention and up to 25 wt. % of the anionic polyelectrolytes of the invention.

-49GB 286834 B6

Further, dispersing mixed compositions of up to 90 wt. % of the cationic polyelectrolytes of the invention and up to 20 wt. % of anionic polyelectrolytes of the invention.

Very particularly preferably, dispersing blend compositions of 80 or 80 are suitable. 90 wt. % of cationic polyelectrolytes according to the invention and 10 wt. % of the anionic polyelectrolytes of the invention.

Preferably, the ratio of the cationic polyelectrolyte mixture to the amphoteric cationic polyelectrolyte in the mixture with the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte is 0 to 100 wt. % cationic polyelectrolyte and 100 to 0 wt. % amphoteric cationic polyelectrolyte. Further preferably, the mixing ratio is 0 to 30 wt. % cationic polyelectrolyte and 70 to 100 wt. an amphoteric cationic polyelectrolyte, in particular a mixed ratio of 0 to 20 wt. % cationic polyelectrolyte and 80 to 100 wt. % amphoteric cationic polyelectrolyte.

Preferably, the molar composition of the individual components in the partially neutralized anionic polyelectrolyte is admixed with the cationic and / or amphoteric cationic polyelectrolyte. between 0 mol% to 100 mol% acrylic acid and 100 ml to 0 mol% other monomers. Other monomers containing carboxyl groups and / or sulfo groups and / or acid groups of phosphoric acid esters are preferred.

Particularly preferably, the molar composition of the individual components in the partially neutralized amphoteric anionic polyelectrolyte is mixed with a cationic and / or amphoteric cationic polyelectrolyte. between 0 mol% to 99 mol% acrylic acid and 100 mol% to 1 mol% other monomers.

Extremely good results are obtained when the other monomers containing carboxy and / or sulfo groups and / or acid groups of phosphoric acid esters are one or more of the group corresponding to the general formula given in point 6.

It is particularly preferred that the anionic polyelectrolyte is a partially neutralized acrylic acid. Preferably, 2 to 80 mol% of the acid groups of the anionic polyelectrolytes are neutralized, particularly preferably 3 to 70 mol% and very particularly preferably 3 to 10 mol% of the acid groups.

According to the invention, the minerals or the fillers; pigments in particular elements of the second and / or third major group and / or fourth minor group of the Periodic Table of the Elements. Preferably, minerals and / or fillers and / or pigments containing calcium and / or silicon and / or aluminum and / or titanium are used, with calcium and carbonate containing minerals and / or fillers and / or pigments being preferred. Quite particularly preferred are natural calcium carbonate and / or precipitated calcium carbonate and / or marble and / or chalk and / or dolomite and / or dolomite-containing calcium carbonate.

The aqueous suspension preferably consists of 97.0 wt. % to 99.89 wt. % of minerals and / or fillers and / or pigments and water and 0.11 wt. % to 3.0 wt. % of a mixture of cationic and / or amphoteric cationic and partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte, with a solids content of 60 to 80 wt. % based on dry mineral, respectively. dry filler, resp. dry pigment.

It is further preferred that the aqueous suspension consists of 98.5 wt. % to 99.8 wt. % of minerals and / or fillers and / or pigments and water, and 0.2 wt. % to 1.5 wt. % of a mixture of cationic and / or amphoteric cationic and partially neutralized anionic and / or partially neutralized

% Of an amphoteric anionic polyelectrolyte, with a solids content of 60 to 75 wt. %, based on dry mineral, respectively. dry filler, resp. dry pigment.

Further, good results are obtained when the aqueous suspension consists of 99.2 wt. % to 99.65 wt. % of minerals and / or fillers and / or pigments and water, and 0.35 wt. % to 0.8 wt. % of a mixture of cationic and / or amphoteric cationic and partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes, with a solids content of 60 to 70 wt. %, based on dry mineral, respectively. dry filler, resp. dry pigment.

Excellent results are obtained when the aqueous suspension consists of 99.6 wt. %, respectively. 99.05 wt. %, respectively. 99.1 wt. % of minerals and / or fillers and / or pigments and water, and 0.4 wt. %, respectively. 0.95 wt. %, respectively. 0.9 wt. % of a mixture of cationic and / or amphoteric cationic and partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes, with a solids content of 67 wt. %, respectively. 67 wt. %, respectively. 60 wt. %, based on dry mineral, respectively. dry filler, resp. dry pigment, at such a grain size that 60 wt. %, respectively. 70 wt. %, respectively. 90 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm.

Preferably, the anionic polyelectrolyte and / or the amphoteric anionic polyelectrolyte in admixture with the cationic and / or amphoteric cationic polyelectrolyte is partially neutralized by a mono- and / or polyvalent cation. Particularly good results are obtained when the anionic polyelectrolyte and / or the amphoteric anionic polyelectrolyte in admixture with the cationic and / or amphoteric cationic polyelectrolyte is partially neutralized by alkali metal cations and / or amines and / or alkanolamines and / or quaternary ammonium compounds, in particular Na ⁺ ammonium compounds and in particular Na ⁺ and / or Ca ²⁺ and / or Mg ²⁺ .

The viscosity limit, in the aqueous suspension of spent cationic and / or amphoteric cationic polyelectrolytes, is preferably between 9.2 ml / g and 48.5 ml / g, but particularly preferably between 16.2 ml / g and 31.2 ml / g.

A further advantageous feature of the method according to the invention is characterized in the following method steps:

a) an aqueous suspension of minerals and / or fillers and / or pigments is wet-ground together with the dispersing and grinding aid according to the invention, with the addition of:

(b) the part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes prior to grinding; and

(c) a part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes during grinding; and / or

(d) the part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes after grinding,

e) and cationic and / or amphoteric cationic polyelectrolyte at the same time before milling or only

(f) part of the cationic and / or amphoteric cationic polyelectrolytes prior to milling; and

(g) part of cationic and / or amphoteric cationic polyelectrolytes during grinding, and / or

(h) a portion of the cationic and / or amphoteric cationic polyelectrolytes after grinding.

-51EN 286834 B6

Particularly preferred is the method in which it is added

a) 10 to 90 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte prior to grinding, and

b) 10 to 90 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte during grinding and / or

c) 0 to 80 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte after grinding,

d) 50 to 100 wt. % cationic and / or cationic amphoteric polyelectrolyte prior to milling; and

e) 0 to 50 wt. % of cationic and / or cationic amphoteric polyelectrolyte during grinding and / or

f) 0 to 50 wt. % cationic and / or amphoteric cationic polyelectrolyte after grinding.

Good results are obtained when the method in which it is added is used

a) 20 to 40 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte prior to grinding, and

b) 60 to 80 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte during grinding and / or

c) 0 to 20 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte after grinding,

d) 50 to 100 wt. % cationic and / or cationic amphoteric polyelectrolyte prior to milling; and

e) 0 to 50 wt. % of cationic and / or cationic amphoteric polyelectrolyte during grinding and / or

f) 0 to 50 wt. % cationic and / or amphoteric cationic polyelectrolyte after grinding.

Very good results are obtained when the method in which it is added is used

a) 25 to 35 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte prior to grinding, and

b) 65 to 75 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte during grinding and / or

c) 0 to 10 wt. % partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte after grinding, and

d) 70 to 100 wt. % cationic and / or cationic amphoteric polyelectrolyte prior to milling; and

e) 0 to 30 wt. % of cationic and / or cationic amphoteric polyelectrolyte during grinding and / or

-52EN 286834 B6

f) 0 to 30 wt. % cationic and / or amphoteric cationic polyelectrolytes after grinding.

Excellent results are obtained in the way it is added

a) 30 wt. % of partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes prior to grinding, and

b) 70 wt. % of partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes during grinding, and

c) 100 wt. % cationic and / or cationic amphoteric polyelectrolytes prior to grinding.

According to the invention, aqueous suspensions of minerals and / or fillers and / or pigments are used in papermaking in the paper industry. Other applications relate to the surface treatment (pigmentation) of the papim surface in a size press of a papermaking machine for use in papim coatings, in a primer coat or in a primer. in topcoat, in wood pulp to combat interfering substances (pitch control), in circulating water of paper machines to reduce CSB (reduction of oxygen consumption), in wastewater treatment plants, to flocculate anionically stabilized pigment and / or mineral suspensions and / or fillers in the paper industry, or to flocculate (immobilize) coating paints in paint shops.

The process according to the invention has succeeded in preparing a suspension of mineral and / or filler and / or pigment by grinding at a high solids content of> 60 wt. %, in which the mineral and / or filler and / or pigment particles are both electrostatically positive and probably also sterically stabilized, and the viscosity of the suspension remains stable for weeks and e.g. retention in paper production is excellent.

Surprisingly and unexpectedly, when a suitable combination of one or more cationic polyelectrolytes and / or one or more amphoteric cationic polyelectrolytes and one or more partially neutralized anionic polyelectrolytes and / or one or more amphoteric anionic partially neutralized polyelectrolytes as well as appropriately determining the addition of polyelectrolytes before, during and / or after grinding (grinding process), at the high shear forces and temperatures that occur during wet grinding, there is no mutual neutralization of the oppositely charged polymers and therefore coagulation of the polymer. In contrast, optimum grinding and suspension stabilization are due to the fact that the anionic polyelectrolytes of the invention

(a) appears to act as a bridging between the mineral and / or filler particles and / or pigments and the cationic and / or amphoteric cationic polyelectrolytes of the invention, which cationic and / or amphoteric cationic polyelectrolyte fixed on the surface of the mineral and / or filler and / or pigment mineral particles and / or fillers and / or pigments have a positive charge and thus leads to an electrostatically positive stabilization of the system and

b) according to the invention, by further addition of anionic polyelectrolytes during and / or after grinding, these appear to act as bridges between cationic polymer chains of cationic and / or amphoteric cationic polyelectrolytes, possibly resulting in a superstructure that sterically stabilizes mineral and / or filler particles and / or pigment; resulting in a considerably low, stable viscosity at high concentration than when the entire amount of the anionic polyelectrolytes of the invention is added at the beginning of grinding.

It is also surprising and unexpected that the degree of neutralization of the anionic polyelectrolytes according to the invention by mono- and / or polyvalent cations has a decisive influence on the stability at

The storage of a suspension of minerals and / or fillers and / or pigments, i.e. for the time stability of the viscosity of the suspension.

With the feed of 100 mol% sodium neutralized anionic polyelectrolytes as used in the examples of EP 0 278 602, the viscosity increases so strongly over time that the suspension becomes unusable.

In contrast, when using anionic polyelectrolytes and / or amphoteric anionic polyelectrolytes partially neutralized by the mono- and / or polyvalent cations of the invention, the viscosity remains stable for days to weeks in proportion to the degree of neutralization. The lower the degree of neutralization by mono-ionic cations, the better the storage stability. Neutralization steps of 5 to 10 mol% are most suitable. Multivalent cations, such as calcium and / or magnesium, have a slight negative effect on storage stability.

In the case of non-neutralized anionic polyelectrolytes, especially polyacrylic acid, there is a problem that usually a 40 wt.% Aqueous polymer solution is very highly viscous and also a normal crystallization temperature is 0 ° C. Polyacrylic acid crystallizes already at 20 ° C. This leads to dosing problems, especially in cold seasons and especially in Scandinavia. This results in irregular dosing which leads to large fluctuations in the viscosity of the produced mineral and / or filler suspensions and / or pigments.

However, this is not the case with the anionic polyelectrolytes of the invention.

Good storage stability with regard to viscosity and susceptibility to settling is of decisive importance, especially during transport and in large storage tanks, to prevent the destruction of goods. With the mineral and / or filler and / or pigment suspension produced according to the invention, it is possible to freely select the place of manufacture (the place of production of the mineral and / or filler and / or pigment suspension) and also the place of use (eg paper mill). Thus, the site of production may adapt to the geological occurrence of mineral and / or filler and / or pigment deposits and may not, for purely logical reasons, respect the location of the customer.

Aqueous suspension of minerals and / or fillers and / or pigments with a solids content of> 60 wt. %, based on dry mineral and / or filler and / or pigment, is prepared according to the invention by grinding the coarse pulverized feedstock, wherein the combination of partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes and cationic and / or amphoteric cationic polyelectrolytes are employed in the process so that the whole or. a portion of the cationic and / or amphoteric cationic polyelectrolytes and only a portion of the partially neutralized anionic polyelectrolytes and / or the partially neutralized amphoteric anionic polyelectrolytes are deployed at the beginning of the milling, and another portion of the anionic polyelectrolytes of the invention is added during milling and / or after milling to reduce viscosity.

Although the cationic and / or amphoteric cationic polyelectrolyte is present in excess and thus has a positive charge on the mineral and / or filler particles and / or pigments, it causes an additional addition of anionic and / or amphoteric anionic polyelectrolytes of the invention during milling and / or after milling unpredictable enormous viscosity reduction.

Partial neutralization of the anionic and / or amphoteric anionic polyelectrolytes of the invention with single and / or polyvalent cations provides very stable viscosity for many weeks. This effect cannot be achieved by any prior art system.

In the examples of the prior art, grinding must be interrupted to block the mill before the desired fineness is reached. Blocking of the mill occurs due to an enormous increase in viscosity during grinding.

-54GB 286834 B6

The increase in viscosity is believed to be due to the fact that normal cationic polymer polyelectrolytes react with the polymeric anionic polyelectrolytes to form a salt and neutralize and fall apart. Surprisingly, this does not occur with the combination of the polyelectrolytes and the method of addition according to the invention, but rather, the viscosity reduction is not clearly explained. This anionic and / or amphoteric anionic polyelectrolyte according to the invention, during grinding and / or additionally added, does not neutralize the cationic and / or amphoteric cationic polyelectrolytes as would be expected. This, especially for the paper industry, of the ideal grain size, concentration and low viscosity of mineral and / or filler and / or pigment suspensions can be prepared by the process of the invention in a single operation, which represents tremendous economic and qualitative progress.

Preferably, the concentration of the aqueous suspension is 60 to 70% by weight. %, based on dry mineral.

Preferably, the feedstock has a mean equivalent spherical particle diameter of 10 to 50 µm (measured on a Sedigraph 5100) prior to grinding according to the invention.

Thus, during grinding, the anionic and / or amphoteric anionic polyelectrolyte of the invention, which uses its chemical properties, serves to form a bridge between the mineral and / or filler and / or pigment on the grinding of newly formed surfaces of minerals and / or fillers and / or pigments; cationic and / or amphoteric cationic polyelectrolyte. The cationic and / or amphoteric cationic polyelectrolyte fixed therewith sufficiently provides a positive charge to the mineral and / or filler particles and / or pigment. In addition, perhaps the anionic and / or amphoteric anionic polyelectrolyte of the invention, with the chain length of the invention, added in further steps to the mineral and / or filler and / or pigment suspension, acts as a bridge between the polymeric cationic and / or amphoteric cationic polyelectrolyte chains. leads to greater bonds of polymer chains, which apparently additionally sterically stabilize the mineral particles. In grinding, the cationic and / or amphoteric cationic polyelectrolyte, which, supported by the anionic and / or amphoteric anionic polyelectrolyte of the invention, appears to coat the mineral and / or filler and / or pigment surfaces as positive charge carriers and stabilizes the mineral and / or filler particles positively. / or pigment.

In addition, the apparent bridge formation between the anionic and / or amphoteric anionic polyelectrolyte and the cationic and / or amphoteric cationic polyelectrolyte appears to achieve steric stabilization of the mineral and / or filler particles and / or pigment.

Suitable mixtures of anionic and / or amphoteric anionic polyelectrolytes and cationic and / or amphoteric cationic polyelectrolytes prior to grinding are according to the invention:

partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte to cationic and / or amphoteric cationic polyelectrolytes 1:10 to 1:40 preferably for marble 1:12, for chalk "Champagne" 1:30.

During and / or after grinding, the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolyte is added again, depending on the concentration and the desired final viscosity. Preferably approx. twice as much as before grinding.

-55GB 286834 B6

Other examples of the invention

Example 11

As Example 1a (prior art) but partially neutralized polyacrylic acid as in Example 12.

Viscosity in mPa.s after 1 hour_____________________1 days_________________________15 days

144 152 280

Example 11 clearly shows that significantly better storage stability over several weeks is achieved with partially neutralized polyacrylic acid compared to Example 1a (prior art).

Example 12 wt.% Aqueous slurry of natural marble having a grain size of 60 wt. % of particles exhibited an equivalent spherical diameter < 2 µm (measured on Sedigraph 5100), was dispersed with 0.33 wt. %, based on dry marble, of the following copolymer (amphoteric cationic polymer).

a = 95 mol% b = 5 mol% viscosity limit (27.3 ml / g) as well as with 0.06 wt. %, based on dry marble, of sodium partially neutralized polyacrylic acid (10 mol% of carboxyl groups neutralized) of different specific viscosities resp. molecular weight, with vigorous stirring (8000 rpm, mixing disc diameter 50 mm). The aim of this test series was to determine the optimum specific viscosity, respectively. mol. by weight of partially neutralized anionic polyelectrolytes.

-56GB 286834 B6

spec, viscosity of partially neutralized polyacrylate suspension viscosity 0.2 2640 mPa.s 0.35 370 mPa.s 0.54 350 mPa.s 0.71 1420 mPa.s

The optimal spec, the viscosity of the partially neutralized polyacrylate is about 0.35 to 0.54.

Example 13 wt.% Aqueous slurry of natural marble having a grain size of 60 wt. % of the particles exhibited an equivalent spherical diameter <2 µm (measured on Sedigraph 5100), was dispersed with 0.33 wt. %, based on dry marble, of the copolymers of Example 12, but with different viscosity and viscosity limits. molecular weight, and with 0.06 wt. %, based on dry marble, of a partially neutralized polyacrylate of Example 12 having a specific viscosity of 0.35, with vigorous stirring (8000 rpm, agitator disc diameter 50 mm).

limit viscosity of cationic copolymers suspension viscosity 1 hour after dispersion 9.2 ml / g 730 mPa.s 12.8 ml / g 500 mPa.s 15.5 ml / g 350 mPa.s 16.2 ml / g 156 mPa.s 31.2 ml / g 112 mPa.s 48.5 ml / g 840 mPa.s

The optimal cut-off viscosity of the cationic copolymers used is between 15 ml / g and 40 ml / g.

Example 14 wt.% Aqueous slurry of natural marble having a grain size of 60 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on Sedigraph 5100), was dispersed with 0.33 wt. %, based on dry marble, of the copolymers of Example 12 and with 0.06 wt. %, based on dry marble, of polyacrylic acids (specific viscosities 0.35) with different degrees of neutralization of the carboxyl groups with sodium hydroxide, with vigorous stirring (8000 rpm, agitator disc diameter 50 mm).

the degree of neutralization of the polyacrylic acid carboxylic acids after 1 hour suspension viscosity in mPa.s. after 18 days after 6 days after 12 days 100 mol% neutr. 148 640 1560 > 3000 70 mol% neutr. 128 350 1075 1420 50 mol% neutr. 112 176 720 1075 30 mol% neutr. 112 172 460 720 10 mol% neutr. 112 128 172 156

-57GB 286834 B6

The best long-term stability is obtained with a polyacrylic acid in which 5-10 mol% of the carboxyl groups are neutralized.

Example 15 wt.% Aqueous slurry of natural marble having a grain size of 60 wt. % of particles exhibited an equivalent spherical diameter < 2 µm (measured on Sadigraf 5100), was dispersed with 0.33 wt. %, based on dry marble, of a different percent molar composition of the copolymer of Example 12 and 0.06 wt. %, based on dry marble, of partially neutralized polyacrylate (spec, viscosity 0.35, from Example 12) with vigorous stirring (8000 rpm, agitator disc diameter 50 mm).

Mol% cationic monomer 80 mol% 87 mol% 95 mol%

100 mole% mole% of anionic monomer 20 mole% 13 mole% mole% 0 mole% viscosity of the suspension after 1 hour 680 mPa.s 580 mPa.s 172 mPa.s 420 mPa.s

The optimal monomer composition of the cationic polyelectrolytes is about 95 mol% of the cationic compound and 5 mol% of the anionic compound.

Example 16% by weight aqueous slurry of natural marble with equivalent spherical mean particle diameter of 12 µm (measured on Sedigraph 5100) was milled according to the following recipe in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) to a grain size curve such that 60 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g of marble g of an amphoteric cationic polymer corresponding to the formula of Example 12

1.35 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added before grinding

3.15 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added during grinding

2472 g of water

Viscosity: after 2 hours 1 day 5 days 10 days 20 days [mPa.s] 200 116 148 104 104

In Example 16, it is clearly shown that in the type and combination of anionic and cationic polyelectrolytes of the invention, as well as milling, a fine-grained suspension of minerals and / or fillers and / or pigments of low and stable viscosity for weeks is prepared.

-58GB 286834 B6

Example 17% by weight of an aqueous suspension of "Champagne" chalk with an equivalent spherical mean particle diameter of 12 µm (measured on Sedigraph 5100) was ground according to the following recipe in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm) to a grain size curve such that 67 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g of "Champagne" chalk g of the amphoteric cationic polymer of Example 12

0.5 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added before grinding

2472 g of water

Viscosity: after 1 hour [mPa.s] 2400 1 days 3900 5 days> 5000 10 days 20 days 2.5 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added 5 min after grinding with vigorous stirring (8000 rpm, mixing disc diameter 50 mm) Viscosity: after 1 hour [mPa.s] 235 1 days 230 5 days 200 10 days 200 20 days 210

In Example 17 it is clearly shown that the later addition of the anionic polyelectrolytes of the invention also results in an enormous decrease in viscosity and the viscosity remains stable for weeks.

Example 18 wt.% Aqueous slurry of natural marble with an equivalent spherical mean particle diameter of 12 µm (measured on Sedigraph 5100) was milled as follows in Dynomill (0.6 1 grinding container) using glass grinding bodies (0 1 mm). per particle size curve such that 88 wt. % of the particles showed an equivalent spherical diameter < 2 µm (measured on Sedigraph 5100).

Regulation:

5000 g of marble g of the amphoteric cationic polymer of Example 12

1.35 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added before grinding

2.65 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added during grinding

3363 g of water

Viscosity: after 1 hour 1 day 4 days 8 days 11 days [mPa.s] 500 520 400 400 390

Also, the high finenesses found in recipe formulations can be easily obtained by grinding the coarsely ground raw material at high concentrations.

-59EN 286834 B6

Example 19% by weight of an aqueous suspension of natural chalk "Champagne" with an equivalent spherical mean particle diameter of 18 µm (measured on Sedigraph 5100) was ground according to the following recipe in Dynomill (0.6 1 grinding container) using glass grinding bodies (0). 1 mm) per grain curve so that 67 wt. % of the particles showed an equivalent spherical diameter <2 µm (measured on Sedigraph 5100).

Regulation:

5000 g chalk "Champagne"

37.5 g of the amphoteric cationic polymer of Example 12

1.35 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added before grinding

7.65 g of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added during grinding

2486 g of water

Viscosity: after 1 h 1 day 4 days 7 days [mPa.s] 212 170 132 124

Example 20

On a pilot scale, natural marble was used in Example 16, ground in a vertically arranged bead mill (Süssmeier of 180 L) using glass grinding bodies (0-2 mm) to a grain size curve such that 63 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on a Sedigraph 5100) at a concentration of 67.6 wt. % solids.

In a batch of about 600 kg, 501 of this suspension was produced.

Regulation:

400 kg of marble

1.4 kg of the amphoteric cationic polymer of Example 12

0.12 kg of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added before grinding

0.24 kg of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added during grinding

197 kg of water

The hourly output of the bead mill was 500 l of suspension / hour.

Viscosity: after 1 h 1 days 7 days 14 days 21 days cP 230 230 150 150 160

Example 21

On a pilot scale, the marble used in Example 16 was milled in a vertically arranged bead mill (Süssmeier with a content of 1801) using glass grinding bodies (0-2 mm) to a grain distribution curve such that 70 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on a Sedigraph 5100) at a concentration of 70.6 wt. % solids.

-60GB 286834 B6

In a batch of about 600 kg, 41 of this suspension were produced.

Regulation:

400 kg of marble

2.0 kg of the amphoteric cationic polymer of Example 12

0.12 kg of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added before grinding

0.36 kg of polyacrylic acid (spec, viscosity 0.54), 5 mol% of carboxyl groups neutral. NaOH, added during grinding

168 kg of water

The hourly output was 500 l of suspension / hour.

Viscosity: after 1 h 1 days 7 days 14 days 21 days

450 420 400 400 400

Example 22 wt.% Aqueous titanium dioxide slurry having a grain distribution such that 94 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on a Sedigraph 5100), was dispersed under strong shear forces (8000 rpm, agitator disc diameter 50 mm).

Regulation:

1500 g of TiO ₂ g of amphoteric cationic polymer of Example 12 and added

640 g of water

Viscosity: after 1 h 1 day 10 days 20 days [mPa.s] 275 - 300 290

Example 23 wt.% Aqueous titanium dioxide slurry having a grain distribution such that 94 wt. % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on a Sedigraph 5100), was dispersed at strong shear forces (8000 rpm, mixing disc diameter (50 mm)).

Regulation:

1250 g of TiO ₂ g of amphoteric cationic polymer of Example 2 and added

675 g of water

Viscosity: after 1 hour 1 days 10 days 20 days [mPa.s] 350 370 400 420

-61EN 286834 B6

Example 24 wt.% Aqueous suspension of natural CaSO ₄ having a grain distribution such that 23 wt. % of the particles exhibited an equivalent spherical diameter <2 µm (measured on a Sedigraph 5100), was dispersed under strong shear forces (8000 rpm mixing disc diameter (50 mm)).

Regulation:

1000 g CaSO ₄

3.6 g of the amphoteric cationic polymer of Example 12 and added

670 g of water

Viscosity: after 1 h 1 day 10 days 20 days [mPa.s] 350 390 400

Example 25 wt.% Aqueous CaCO ₃ slurry (74.5 wt. Slurry from Example 7A) and dry talc; % of the particles exhibited an equivalent spherical diameter < 2 µm (measured on Sedigraph 5100), was dispersed at strong shear forces (8000 rpm, stirring disc diameter 50 mm) to form a 1: 1 talc / CaCO ₃ mixture.

Regulation:

670 g of the 74.5% suspension of Example 7A

549 g of dry talc 91%

2.8 g of the amphoteric cationic polymer of Example 12 and added

594 g of water

Viscosity: after 1 h 1 days 2 days [mPa.s] 450 500

Application example

The retention of the marble suspension prepared in Examples 20 and 21 in papime production was investigated compared to the marble suspension prepared today usually with anionic dispersants.

Test conditions:

Substance: 80% birch sulphate degree of grinding 23 ° SR% pine sulphate

Retention aid: 0.05% polyacrylamide (viscosity limit 700 ml / g)

Britt-Jar Papers Research Material, SYRACUSE, USA:

1.275 ml of a 2% fibrous suspension (3.63 g of absolutely dry fibers) and 275 ml of distilled water are placed in a Britt-Jar beaker;

-62EN 286834 B6

2. Set the Britt-Jar- (ovo) stirrer to 700 rpm;

3. Add 25.4 ml of a 5% mineral and / or filler suspension and / or pigment

4. Add the appropriate amount of retention agent after 20 s

5. After a further 25 seconds, open the drain cock and allow 100 ml of sieve water to drain.

6. In the sieve water, the proportion of CaCO ₃ is determined complexometrically after decomposition with HCl or by melting - AAS. For other minerals and / or fillers and / or pigments, the sieve water is filtered through a membrane filter, ashed at 600 ° C by alkaline thermal decomposition, eg with NaOH / KOH in a zirconium crucible, converted to anhydrous form and determined in acidified state by AAS . The content of the minerals and / or fillers and / or pigments may be determined with respect to the respective conversion factors.

7. From the registered fraction of minerals and / or fillers and / or pigments per 100 ml and from the sieved water fraction of minerals and / or fillers and / or pigments per 100 ml, retention of the filler can be calculated.

Results:

Products: ______________________

Anionic stabilized suspension with 60% <2 pm (0.15% sodium polyacrylate spec, viscosity 0.35)

Anionic stabilized suspension with 70% <2 pm (0.3% natriumpolyacrylate spec, viscosity 0.54)

Suspension of Example 19 filler retention at first application of 41.1%

35.3%

61.9%

The suspension of Example 20

67.8%

By using the marble suspension produced by the novel process of the invention, it is possible to increase the retention of the filler without adversely affecting the paper formation, which represents a huge development leap.

The aqueous suspensions as well as the process according to the invention have the following advantages:

in contrast to known methods, it is possible to produce a highly concentrated (> 60 wt.%) suspension of minerals and / or fillers and / or pigments by wet grinding the coarse shredded raw material.

suspensions exhibit excellent storage stability at low viscosity.

- in use, this entails, for example, great advantages, particularly with regard to the retention of filler in paper production.

- grinding and dispersion is possible at high grinding forces and at the boiling point of water.

-63EN 286834 B6

Claims (27)

An aqueous suspension of minerals and / or fillers and / or pigments containing > 60% solids by weight based on dry mineral or dry filler or dry pigment, wherein the mineral or filler or pigment is dispersed by at least one dispersant, characterized in that comprising a dispersant comprising at least one amphoteric polyelectrolyte, wherein the number of negative charges in the anionic monomer units is equal to the number of positive charges in the cationic monomer units, optionally containing additionally neutral monomer units, and / or at least one amphoteric cationic polyelectrolyte monomer, charges, and / or at least one amphoteric anionic polyelectrolyte, in which the non-neutral monomer units carry predominantly negative charges, and / or at least one partially neutralized anionic polyelectrolyte, and / or at least one partially neutral Amphoteric anionic polyelectrolyte, in which the non-neutral monomeric units carry predominantly negative charges, wherein the amphoteric, amphoteric cationic and amphoteric anionic polyelectrolytes contain quaternary ammonium groups, and the filler and / or pigment and / or mineral particles which bear a charge which is . Aqueous suspension of minerals and / or fillers and / or pigments according to claim 1, containing> 60% by weight of solids based on dry mineral or dry filler or dry pigment, wherein the mineral or filler or pigment is dispersed with a dispersant containing cationic polyelectrolyte and anionic the polyelectrolyte and the cationic polyelectrolyte are in an amount in which the dispersed mineral or filler particles or pigments carry a positive charge, characterized in that the dispersant is a mixture of one or more cationic polyelectrolytes and / or one or more amphoteric cationic polyelectrolytes in which the nonneutral monomer units have and one or more partially neutralized anionic polyelectrolytes and / or one or more partially neutralized amphoteric anionic polyelectrolytes in which the non-neutral monomeric units have a predominantly negative charge. An aqueous suspension according to claim 2, characterized in that it comprises a dispersant which is a mixture of one or more homopolymic cationic polyelectrolytes and / or one or more copolymeric amphoteric cationic polyelectrolytes in which the non-neutral monomer units have a predominantly positive charge, and one or more homo- and / or copolymeric partially neutralized anionic polyelectrolytes and / or one or more amphoteric anionic partially neutralized polyelectrolytes in which the non-neutral monomer units have a predominantly negative charge. The aqueous suspension of claim 1, further comprising at least one cationic polyelectrolyte. -64GB 286834 B6 Aqueous suspension according to claim 1 or 4, characterized in that it contains a dispersant which is a mixture (a) at least one cationic polyelectrolyte and / or at least one amphoteric cationic polyelectrolyte, in which the non-neutral monomeric units carry predominantly positive charges, and b) at least one partially neutralized anionic polyelectrolyte and / or at least one partially neutralized amphoteric anionic polyelectrolyte, wherein the non-neutral monomer units carry predominantly negative charges, wherein the cationic polyelectrolyte and / or the amphoteric cationic polyelectrolyte are present in an amount of particles or particles or pigment carry positive charges. Aqueous suspension according to claim 2 or 3, characterized in that it contains a dispersant containing a cationic polyelectrolyte and / or an amphoteric cationic polyelectrolyte, in which the non-neutral monomeric particles have predominantly positive charges which carry a functional group in the ethylene backbone substituent which produces positive. cartridges. Aqueous suspension according to any one of the preceding claims, characterized in that it contains an amphoteric anionic and cationic and an amphoteric cationic polyelectrolyte carrying a positive charge functional group in the ethylene backbone substituent and comprising quaternary ammonium groups, carboxyl groups and / or sulfone groups and / or or an acidic phosphoric acid ester containing groups, wherein the substituent carrying a cationic charge is linked to the backbone via a -C (= O) -NH- or -C (= O) O- group. Aqueous suspension according to claims 2, 3 and 6, characterized in that it comprises an amphoteric cationic polyelectrolyte in which the substituent carrying a cationic charge is linked to the main chain via a -C (= O) NH- or -C (= O) group. -O-. An aqueous suspension according to any one of the preceding claims, characterized in that it comprises an anionic partially neutralized and amphoteric anionic partially neutralized polyelectrolyte with carboxyl groups, wherein the anionic partially neutralized polyelectrolyte is a homopolymic and / or copolymeric polyelectrolyte. Aqueous suspension according to any one of the preceding claims, characterized in that it contains at least one compound of the general formula I as amphoteric anionic and amphoteric cationic polyelectrolyte. -65EN 286834 B6 - Rs 1 Ri 1 Re 1 R7 1 C in Re 1 OC1 1 R9 1 z X 1 Y ( - R2- n * -r ₄ R 3 CAn> - and in which R 1, R 5, R 5 and R ₇ denote H, and / or R to R ₇ denotes a _{C] g} alkyl, especially alkyl, optimally CH ₃ or H, and / or C ₆ aryl, especially unsubstituted, R 8 and R ₉ denote H and / or C _1-8 alkyl, in particular C 1-6 alkyl, preferably CH ₃ and / or H, and / or C 8 aryl, in particular unsubstituted, with the substitution being preferred, R 1 is H or CH ₃ , R ₂ and R ₃ are CH ₃ or C ₂ H ₅ , R 4 is CH ₃ to C ₄ H ₉ and its isomers, R ₅ and R ₈ are H, R ₇ is H or CH ₃ , R 8 and R ₉ are H, X is O or NH, Y is CH ₂ and C5H10. Z is -COOH and / or - (CH ₂ ) _n - COOH and / or - (CH ₂ ) _n -SO ₂ OH, where n is 1 to 18, and / or p-phenylene-SO ₂ OH and / or acidic phosphoric acid ester group, a + b are relative amounts of monomers in formula I in the range of 5:95 to 99: 1 and (An) 'is chloride and / or bromide and / or iodide and / or HSO4' and / or CH ₃ SO _4-and / or nitrite. Aqueous suspension according to claim 6, characterized in that it contains compounds of the formula II as polyelectrolytes -66GB 286834 B6 Η Η I »c — c-- I i A C = O AND NH CCII =) ₃ fl3C-N ⁺ -CH3 CH3 (flrT) Η H i I C-c— A f-O) Ιο Γ Z (Ckat) ⁺ (II) in which Z is the fraction c / valence (cat) ⁺ and when c = 0, then Z = 0 and (cat) ⁺ is an alkali metal and / or alkaline earth metal cation and / or an amine and / or an alkanolamine and / or quaternary ammonium cation, (An) - is chloride, bromide, iodide, HSO ₄ ', CH ₃ SO ₄ or nitrite, wherein the polyelectrolytes a, b, c are present in the following proportions anionic amphoteric amphotemia amphoteric cationic a = 49 to 47 mol% b + c = 51 to 53 mol% a = 50 mole% b + c = 50 mole% a = 51 to 80 mol% b + c = 49 to 20 mol% Aqueous suspension according to any one of the preceding claims, characterized in that it contains compounds of the general formula II, in which the substituent Z is partially neutralized with alkali and / or alkaline earth cations, the degree of neutralization being in the range of 1 to 99 mol%. Aqueous suspension according to any one of the preceding claims, characterized in that it contains compounds of the general formula II, in which the degree of neutralization of the substituent Z with alkali metal cations is in the range of 1 to 25 mol%. Aqueous suspension according to any one of the preceding claims, characterized in that it contains compounds of the general formula II, in which the substituent Z is completely neutralized when the cations are bivalent cations, trivalent cations, NH4, primary, secondary or tertiary amines or quaternary ammonium. ions. Aqueous suspension according to any one of the preceding claims, characterized in that it contains compounds of the general formula II, in which the substituent Z is unneutralized. Aqueous suspension according to any one of the preceding claims, characterized in that it contains polyelectrolytes with a pitch ratio of anionic charge to cationic charge in the range of 55:45 to 51:49. Aqueous suspension according to any one of the preceding claims, characterized in that it contains polyelectrolytes, all of which have a neutralization degree of the anionic component, with the exception of pure cationic electrolytes, in the range of 0.1 to 100 mol% in neutralization with alkaline earth cations. -67EN 286834 B6 An aqueous suspension according to any one of the preceding claims, characterized in that it contains at least one compound of the general formula III as a cationic electrolyte. R3 R2 R2c -c1 Rg C »O I X1 is R2-N * -R4 R3 (ftn) - (III) wherein R 1, R ₅ and R ₆ denote H, and / or R 1 to R ₅ denote C 1-6 alkyl and / or C ₆ aryl, R 5 is optionally a group -CXYN ⁺ -R 3 R2 in which X is O and / or NH, Y is -CH ₂ - and --C5H10-, n is 20 to 3000 and (An) is a chloride and / or bromide and / or iodide and / or CH3SO4 and / or nitrite. An aqueous suspension according to any one of the preceding claims, characterized in that as an anionic partially neutralized polyelectrolyte it comprises at least one compound of the general formula IV + IKa ⁱⁿ Iv (IV) in which: -68GB 286834 B6 Z is -COOH, and / or - (CH _{2) n} COOH and / or - _(CH2) ", - SO ₂ OH and / or p-phenylene-SO ₂ OH and / or acid ester group, phosphoric acid, R 1 is H or CH ₃ , R ₂ and R ₃ denote H and / or C 1-6 alkyl and / or C ₆ aryl, and R ₂ or R ₃ optionally denotes Z, when Z is -COOH, u is a charge of +1 and / or +11 and / or + III, K is an alkali metal and / or alkaline earth metal ion, w is 59 to 95 mol% for the number of Z in the monomer, v is 5 to 41 mol% divided by u and n is 1 to 12. Aqueous suspension according to any one of the preceding claims, characterized in that it comprises an anionic polyelectrolyte and / or an amphoteric anionic polyelectrolyte in which 1 to 70 mol% of the acid groups are neutralized, the specific viscosity "Eta" of the partially neutralized anionic polyelectrolyte and / or amphoteric. of the anionic polyelectrolyte in admixture with cationic and / or amphoteric cationic polyelectrolyte, measured in the form of complete salt, is in the range of 0.2 to 1.0 and the degree of polymerization of the cationic polyelectrolyte and / or amphoteric cationic polyelectrolyte in admixture with partially neutralized anionic polyelectrolyte the amphoteric anionic partially neutralized polyelectrolyte, measured by the cut-off viscosity, is in the range of 5-50 ml / g and the cut-off viscosity of the cationic and / or amphoteric cationic polyelectrolyte used in the aqueous suspension is in the range of 9.2 to 48.5 ml / g. An aqueous suspension according to any one of the preceding claims, characterized in that it contains an amphoteric anionic and amphoteric neutral and amphoteric cationic polyelectrolyte with a degree of polymerization in the range of 5 to 150 mPa · s, measured by viscosity. Aqueous suspension according to any one of the preceding claims, characterized in that it contains 97.0 to 99.97% by weight of minerals and / or fillers and / or pigments or water and 0.03 to 3.0% by weight of amphoteric polyelectrolytes containing 60 to 80% by weight, based on dry material and dry filler and dry pigment, respectively. Aqueous suspension according to any one of the preceding claims, characterized in that it contains 97.0 to 99.89% by weight of minerals and / or fillers and / or pigments and water and 0.11 to 3.0% by weight of a cationic and / or mixture. or amphoteric cationic and partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes having a solids content of 60 to 80% by weight, based on dry mineral and dry filler and dry pigment respectively. Aqueous suspension according to any one of the preceding claims, characterized in that it contains minerals and / or fillers and / or pigments containing elements of the second and / or third main groups and / or fourth subgroups of the Periodic Table of the Elements. Aqueous suspension according to any one of the preceding claims, characterized in that it contains natural calcium carbonate, precipitated calcium carbonate and / or marble, chalk, dolomite and / or dolomite containing calcium carbonate as minerals and / or fillers and / or pigments. -69EN 286834 B6 26. A process for the production of an aqueous suspension according to any one of the preceding claims, characterized in that it is: (a) an aqueous slurry of minerals and / or fillers and / or pigments is milled wet with a mixture of dispersants and a mixture of milling aids, (b) polyelectrolytes prior to milling of amphoteria; or (c) part of the amphoteric polyelectrolytes is added before grinding; and (d) a portion of the amphoteric polyelectrolytes is added during grinding, and / or (e) a portion of the amphoteric polyelectrolytes is added after grinding, or (a) an aqueous suspension of minerals and / or fillers and / or pigments is wet milled together with a mixture of dispersants and a mixture of grinding aids, (b) add part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes prior to grinding; and (c) part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes is added during grinding, and / or (d) part of the partially neutralized anionic and / or partially neutralized amphoteric anionic polyelectrolytes is added after grinding; and (e) the cationic and / or amphoteric cationic polyelectrolyte is added prior to grinding, or (f) part of the cationic and / or amphoteric cationic polyelectrolytes prior to grinding; and (g) a portion of the cationic and / or amphoteric cationic polyelectrolytes is added during grinding, and / or h) a portion of the cationic and / or amphoteric cationic polyelectrolytes is added after grinding. Use of an aqueous suspension of minerals and / or fillers and / or pigments according to any one of claims 1 to 25 in the manufacture of papim, optionally treating its surface, pigmenting the papim surface in a papim sizing press and in papim lubrication, pre-lubrication or cover lubrication in the lubrication process, sanding wood to prevent breakage, lubrication waste to prevent breakage, to control resin in the paper pulp, in the water cycle of the paper machine to reduce the need for chemical oxygen, in the waste water treatment finisher, flocculation of anionic stabilized suspensions of pigments and / or minerals and / or fillers in papime production or flocculation and immobilization of the coated paints during coating.