Aqueous polymer dispersions

Abstract

Phosphorus-containing aqueous polymer dispersions and the use thereof as binders in coating formulations.

Claims

1. A process for producing an aqueous polymer dispersion by free-radically initiated aqueous emulsion polymerization, the process comprising: (i) free-radically polymerizing, in an aqueous medium in the presence of at least one phosphorus-containing dispersing aid, in a first polymerization stage (polymerization stage 1), ≥1.0 and ≤3.0% by weight of at least one α,β-monoethylenically unsaturated C.sub.3- to C.sub.6-mono- or -dicarboxylic acid (monomers A1), ≥1.5 and ≤6.0% by weight of at least one ethylenically unsaturated compound comprising at least one phosphorus-containing group (monomers A2), and ≥91.0% and ≤97.5% by weight of at least one ethylenically unsaturated compound distinct from the monomers A1 and A2 (monomers A3), wherein the amounts of the monomers A1 to A3 sum to 100% by weight (total monomer amount 1), to obtain a polymer 1; and, subsequently, (ii) free-radically polymerizing, in the presence of the polymer 1, in a second polymerization stage (polymerization stage 2), ≤0.1% by weight of at least one α,β-monoethylenically unsaturated C.sub.3 to C.sub.6-mono- or -dicarboxylic acid (monomers B1), ≤0.1% by weight of at least one ethylenically unsaturated compound comprising at least one phosphorus-containing group (monomers B2), and ≥99.8% and ≤100% by weight of at least one ethylenically unsaturated compound distinct from the monomers B1 and B2 (monomers B3), wherein the amounts of the monomers B1 to B3 sum to 100% by weight (total monomer amount 2), to obtain a polymer 2, with the proviso that a glass transition temperature Tg.sup.1 of the polymer 1 is ≥−5° C. and ≤10° C., a glass transition temperature Tg.sup.2 of the polymer 2 is ≥10° C. and ≤40° C. and is at least 10° C. above the glass transition temperature Tg.sup.1[Tg.sup.2=Tg.sup.1+≥10° C.], a ratio of the total monomer amount 1 to the total monomer amount 2 is 70% to 85% by weight to 15% to 30% by weight and an amount of the at least one phosphorus-containing dispersing aid is ≥0.5% by weight based on a sum of the total monomer amount 1 and the total monomer amount 2 (total monomer amount).

2. The process of claim 1, wherein the monomers A1 are acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid and/or crotonic acid.

3. The process of claim 1, wherein the monomers A2 are vinylphosphonic acid and/or a (meth)acryloxy(poly)alkoxy phosphate.

4. The process of claim 1, wherein the monomers A3 are to an extent of ≥80% by weight selected from the group consisting of n-butyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate, styrene and methyl methacrylate.

5. The process of claim 1, wherein no monomers B1 and B2 whatsoever are employed.

6. The process of claim 1, wherein the polymerization stages 1 and 2 are performed at a pH in a range of from ≥3 to ≤8 measured at room temperature.

7. The process of claim 6, wherein a pH adjustment is carried out with a base having a boiling point ≤20° C., measured at 1.013 bar (absolute).

8. The process of claim 1, wherein the monomers A3 are to an extent of >0% and ≤20% by weight selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-(acetoacetoxy)ethyl methacrylate, 2-ureidoethyl methacrylate, diacetone acrylamide, glycidyl methacrylate, 3-(methacryloyloxy)propyltrimethoxysilane, vinyltriethoxysilane, allyl methacrylate and 1,4-butanediol diacrylate.

Description

EXAMPLES

Example 1 (Dispersion 1)

(1) In a 2 I polymerization vessel fitted with feeding devices and a temperature control means at 20° C. to 25° C. (room temperature) under a nitrogen atmosphere

(2) 260.0 g of deionized water and

(3) 12.0 g of a 25% by weight aqueous solution of a phosphorus-containing dispersing aid (Rhodafac® RS610/A25)
were initially charged and heated to 90° C. with stirring. Once this temperature had been reached 30.4 g of feed 1 were added and then 33.8 g of a 2.5% by weight aqueous solution of ammonium peroxodisulfate were added over 2 minutes and the mixture was then stirred for a further 10 minutes at the abovementioned temperature. Commencing concurrently with the addition of the ammonium peroxodisulfate solution 32.6 g of a 5.3% by weight aqueous solution of ammonia were continuously added over a period of 175 minutes at a constant flow rate.

(4) After the 10 minutes further stirring time had elapsed and while maintaining a temperature of 90° C. the remainder of feed 1 was continuously added over 90 minutes at a constant flow rate. Commencing concurrently with the addition of the remainder of feed 1 48.4 g of a 2.5% by weight aqueous solution of ammonium peroxodisulfate were likewise continuously added over 90 minutes. The polymerization mixture was then allowed to react at 90° C. for a further 15 minutes. Subsequently, and while maintaining a temperature of 90° C., feed 2 was continuously added over 65 minutes at a constant flow rate. 15.2 g of a 2.0% by weight aqueous solution of ammonium peroxodisulfate were continuously added concurrently with feed 2. After termination of feed 2 the polymerization mixture was allowed to react at 90° C. for a further 20 minutes. The obtained aqueous polymer dispersion was then cooled to 75° C. and commencing concurrently 10.1 g of a 10% by weight aqueous solution of tert-butyl hydroperoxide, and in a simultaneous feed 9.9 g of a 6% by weight aqueous solution of Brüggolit® FF6 M (reducing agent from Bruggemann GmbH & Co. KG), were continuously added over 10 minutes. The polymerization mixture was subsequently stirred at 70° C. for 20 minutes, cooled to room temperature and with stirring admixed with 1.2 g of a 5% by weight aqueous solution of Acticid® MBS (biocide from Thor).

(5) Feed 1 (homogeneous mixture of):

(6) TABLE-US-00001 110.3 g deionized water 12.0 g Rhodafac ® RS610/A25, 2.4 g 30% by weight aqueous solution of a fatty alcohol polyethylene oxide ether sulfate (Disponil ® FES 993 from BASF SE), 196.9 g styrene 196.9 g 2-ethylhexyl acrylate 18.2 g Sipomer ® PAM-200, 14.1 g methyl methacrylate, 22.4 g acetoacetoxyethyl methacrylate, 6.2 g acrylic acid
Feed 2 (homogeneous mixture of):

(7) TABLE-US-00002 42.4 g deionized water 2.4 g Rhodafac ® RS610/A25, 0.6 g Disponil ® FES 993, 12.1 g styrene 133.3 g n-butyl methacrylate

(8) Before further use the obtained polymer dispersion was passed through a 125 μm filter and a coagulate content <0.1% by weight was determined.

(9) The aqueous polymer dispersion obtained after filtration had a solids content of 50.1% by weight. The weight-average particle diameter was determined as 93 nm and the fine coagulate content as 227 μg/g of aqueous polymer dispersion. The pH was determined as 4.2 at the end of the first polymerization stage and as 6.1 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −2.8° C. and a glass transition temperature Tg.sup.2 of 16° C.

(10) The solids contents of the obtained aqueous polymer dispersions were generally determined by drying a defined amount of the aqueous polymer dispersion (about 0.8 g) to constant weight at a temperature of 160° C. using a Mettler Toledo HR73 moisture analyzer. Two measurements were carried out in each case. The value reported in the examples is the average of these two measurements.

(11) To determine the fine coagulate content generally in each case 3.0 g of the obtained aqueous polymer dispersion were diluted to 1500 g with deionized water. After pre-rinsing a Klotz PZG3 sample feeder was used to pump 1000 g of the obtained diluted aqueous polymer dispersion through the Klotz LDS 2×2 sensor at room temperature in 2.5 minutes. In combination with the evaluation and control unit (ABAKUS) with PC interface this afforded the values reported in each case which correspond to the counted particles in the range 10-500 μm.

(12) It should be noted that coagulate contents >0.1% by weight and fine coagulate contents >1000 μg/g of aqueous polymer dispersion can lead to problems in filtration (for example by blocking the filters) and are generally associated with disadvantages in their use in coating compositions through the appearance of surface defects and/or imperfections in the coating.

(13) The weight-average particle diameter was generally determined according to ISO 13321 with a Malvern High Performance Particle Sizer at 22° C. and a wavelength of 633 nm.

(14) The pH was generally determined using a calibrated InPro® 325X pH electrode from Mettler-Toledo GmbH.

(15) The glass transition temperatures were generally determined according to DIN EN ISO 11357-2 (2013-09) by differential scanning calorimetry (DSC) with a heating rate of 20 K/min using a DSC Q2000 instrument from TA Instruments. The midpoint temperatures were used for the determination.

Example 2 (Dispersion 2)

(16) Production of example 2 was carried out completely analogously to the production of example 1 with the exception that in feed 1 the acrylic acid was substituted by the same amount of methacrylic acid.

(17) The obtained polymer dispersion had a solids content of 50.1% by weight. The weight-average particle diameter was 99 nm. The coagulate content was <0.1% and the fine coagulate content was determined as 336 μg/g. The dispersion polymer had a glass transition temperature Tg.sup.1 of −3.5° C. and a glass transition temperature Tg.sup.2 of 17° C.

Example 3 (Dispersion 3)

(18) Production of example 3 was carried out completely analogously to the production of example 1 with the exception that feeds 1 and 2 had the following compositions:

(19) Feed 1 (homogeneous mixture of):

(20) TABLE-US-00003 110.3 g deionized water 12.0 g Rhodafac ® RS610/A25, 2.4 g Disponil ® FES 993, 168.6 g styrene 176.5 g 2-ethylhexyl acrylate 13.1 g Sipomer ® PAM-200, 73.1 g methyl methacrylate, 6.0 g acetoacetoxyethyl methacrylate, 6.7 g acrylic acid
Feed 2 (homogeneous mixture of):

(21) TABLE-US-00004 42.4 g deionized water 2.4 g Rhodafac ® RS610/A25, 0.6 g Disponil ® FES 993, 72.6 g styrene 52.4 g n-butyl methacrylate 8.8 g methyl methacrylate, 22.2 g 2-ethylhexyl acrylate

(22) The obtained polymer dispersion had a solids content of 49.7% by weight. The weight-average particle diameter was determined as 121 nm, the coagulate content as <0.1% by weight and the fine coagulate content as 507 μg/g. The determined glass transition temperatures Tg.sup.1 and Tg.sup.2 were 6° C. and 23° C.

Example 4 (Dispersion 4)

(23) In a 2 I polymerization vessel fitted with feeding devices and a temperature control means at 20° C. to 25° C. (room temperature) under a nitrogen atmosphere

(24) 339.0 g of deionized water and

(25) 10.3 g of Rhodafac® RS610/A25
were initially charged and heated to 90° C. with stirring. Once this temperature had been reached 30.4 g of feed 1 were added and then 33.8 g of a 2.2% by weight aqueous solution of ammonium peroxodisulfate were added over 2 minutes and the mixture was then stirred for a further 10 minutes at the abovementioned temperature. Commencing concurrently with the addition of the ammonium peroxodisulfate solution 40.5 g of a 4.6% by weight aqueous solution of ammonia were continuously added over a period of 175 minutes at a constant flow rate.

(26) After the 10 minutes further stirring time had elapsed and while maintaining a temperature of 90° C. the remainder of feed 1 was continuously added over 90 minutes at a constant flow rate. Commencing concurrently with the addition of the remainder of feed 1 52.8 g of a 2.4% by weight aqueous solution of ammonium peroxodisulfate were likewise continuously added over 90 minutes. The polymerization mixture was then allowed to react at 90° C. for a further 15 minutes. Subsequently, and while maintaining a temperature of 90° C., feed 2 was continuously added over 65 minutes at a constant flow rate. 15.2 g of a 2.0% by weight aqueous solution of ammonium peroxodisulfate were continuously added concurrently with feed 2. After termination of feed 2 the polymerization mixture was allowed to react at 90° C. for a further 20 minutes. The obtained aqueous polymer dispersion was then cooled to 75° C. and commencing concurrently 16.2 g of a 6.8% by weight aqueous solution of tert-butyl hydroperoxide, and in a simultaneous feed 16.0 g of a 4% by weight aqueous solution of Brüggolit® FF6 M, were continuously added over 10 minutes. The polymerization mixture was subsequently stirred at 70° C. for 20 minutes, cooled to room temperature and with stirring admixed with 14.7 g of a 0.4% by weight aqueous solution of Acticid® MBS.

(27) Feed 1 (homogeneous mixture of):

(28) TABLE-US-00005 79.7 g deionized water 12.9 g Rhodafac ® RS610/A25, 2.6 g Disponil ® FES 993, 208.5 g styrene 208.5 g 2-ethylhexyl acrylate 19.5 g Sipomer ® PAM-200, 15.2 g methyl methacrylate, 24.1 g acetoacetoxyethyl methacrylate, 6.7 g acrylic acid 6.5 g vinyltriethoxysilane
Feed 2 (homogeneous mixture of):

(29) TABLE-US-00006 33.5 g deionized water 2.6 g Rhodafac ® RS610/A25, 0.7 g Disponil ® FES 993, 13.0 g styrene 143.3 g n-butyl methacrylate

(30) Before further use the obtained polymer dispersion was passed through a 125 μm filter and a coagulate content <0.1% by weight was determined.

(31) The aqueous polymer dispersion obtained after filtration had a solids content of 49.8% by weight. The weight-average particle diameter was determined as 98 nm and the fine coagulate content as 203 μg/g of aqueous polymer dispersion. The pH was determined as 4.1 at the end of the first polymerization stage and as 6.0 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −5.4° C. and a glass transition temperature Tg.sup.2 of 13° C.

Example 5 (Dispersion 5)

(32) Production of example 5 was carried out completely analogously to the production of example 1 with the exception that 32.6 g of a 5.3% by weight aqueous solution of sodium hydroxide was employed instead of ammonia.

(33) The aqueous polymer dispersion obtained after filtration had a solids content of 50.2% by weight. The weight-average particle diameter was determined as 106 nm, the coagulate content as <0.1% by weight and the fine coagulate content as 373 μg/g of aqueous polymer dispersion. The pH was determined as 4.0 at the end of the first polymerization stage and as 5.9 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −2.3° C. and a glass transition temperature Tg.sup.2 of 15.7° C.

Example 6 (Dispersion 6)

(34) Production of example 6 was carried out completely analogously to the production of example 1 with the exception that 32.6 g of a 5.3% by weight aqueous solution of trimethylamine was employed instead of ammonia.

(35) The aqueous polymer dispersion obtained after filtration had a solids content of 49.9% by weight. The weight-average particle diameter was determined as 98 nm, the coagulate content as <0.1% by weight and the fine coagulate content as 308 μg/g of aqueous polymer dispersion. The pH was determined as 4.5 at the end of the first polymerization stage and as 6.2 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −2.1° C. and a glass transition temperature Tg.sup.2 of 16.5° C.

Comparative Example 1

(36) Production of comparative example 1 was carried out completely analogously to the production of example 1 with the exception that feed 1 comprised no Sipomer® PAM-200 and feed 2 additionally comprised 18.2 g of Sipomer® PAM-200.

(37) The polymerization mixture coagulated during feed 1 so that the experiment had to be aborted.

Comparative Example 2

(38) Production of comparative example 2 was carried out completely analogously to the production of example 1 with the exception that feed 1 comprised no acrylic acid and feed 2 additionally comprised 6.2 g of acrylic acid.

(39) The polymerization mixture coagulated during feed 1 so that the experiment had to be aborted.

Comparative Example 3

(40) Production of comparative example 3 was carried out completely analogously to the production of example 1 with the exception that in the initial charge 25.8 g of Disponil® FES 993 were employed instead of 12.0 g of Rhodafac® RS610/A25, in feed 1 altogether 28.1 g and in feed 2 altogether 5.7 g of Disponil® FES 993 were employed and in each case no Rhodafac® RS610/A25 was employed.

(41) The polymerization mixture coagulated during feed 1 so that the experiment had to be aborted.

Comparative Example 4

(42) Production of comparative example 4 was carried out completely analogously to the production of example 1 with the exception that no 5.3% by weight aqueous solution of ammonia was employed and the polymerization batch coagulated at a pH of 2.3 in the first polymerization stage so that the experiment had to be aborted.

Comparative Example 5 (Comparative Dispersion V5)

(43) Production of comparative example 5 was carried out completely analogously to the production of example 1 with the exception that 16.3 g instead of 32.6 g of a 5.3% by weight aqueous solution of ammonia were employed.

(44) The aqueous polymer dispersion obtained after filtration had a solids content of 50.1% by weight. The weight-average particle diameter was determined as 90 nm, the coagulate content as <0.1% by weight and the fine coagulate content as 689 μg/g of aqueous polymer dispersion.

(45) The pH was determined as 2.9 at the end of the first polymerization stage and as 5.3 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −2.8° C. and a glass transition temperature Tg.sup.2 of 15° C.

Comparative Example 6 (Comparative Dispersion V6)

(46) Production of comparative example 6 was carried out completely analogously to the production of example 1 with the exception that 48.9 g instead of 32.6 g of a 5.3% by weight aqueous solution of ammonia were employed.

(47) The aqueous polymer dispersion obtained after filtration had a solids content of 49.8% by weight. The weight-average particle diameter was determined as 96 nm, the coagulate content as 0.2% by weight and the fine coagulate content as 1083 μg/g of aqueous polymer dispersion. The pH was determined as 4.9 at the end of the first polymerization stage and as 7.3 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −2.0° C. and a glass transition temperature Tg.sup.2 of 15° C.

Comparative Example 7 (Comparative Dispersion V7)

(48) In a 2 I polymerization vessel fitted with feeding devices and a temperature control means at room temperature under a nitrogen atmosphere

(49) 260.0 g of deionized water and

(50) 12.0 g of Rhodafac® RS610/A25
were initially charged and heated to 90° C. with stirring. Once this temperature had been reached 30.4 g of feed 1 were added and then 33.8 g of a 2.5% by weight aqueous solution of ammonium peroxodisulfate were added over 2 minutes and the mixture was then stirred for a further 10 minutes at the abovementioned temperature. Commencing concurrently with the addition of the ammonium peroxodisulfate solution 32.6 g of a 5.3% by weight aqueous solution of ammonia were continuously added over a period of 175 minutes at a constant flow rate.

(51) After the 10 minutes further stirring time had elapsed and while maintaining a temperature of 90° C. the remainder of feed 1 was continuously added over 175 minutes at a constant flow rate. Commencing concurrently with the addition of the remainder of feed 1 60.7 g of a 2.5% by weight aqueous solution of ammonium peroxodisulfate were likewise continuously added over 170 minutes. After termination of feed 1 the polymerization mixture was allowed to react at 90° C. for a further 20 minutes. The obtained aqueous polymer dispersion was then cooled to 75° C. and commencing concurrently 10.1 g of a 10% by weight aqueous solution of tert-butyl hydroperoxide, and in a simultaneous feed 9.9 g of a 6% by weight aqueous solution of Brüggolit® FF6 M, were continuously added over 10 minutes. The polymerization mixture was subsequently stirred at 70° C. for 20 minutes, cooled to room temperature and with stirring admixed with 1.2 g of a 5% by weight aqueous solution of Acticid® MBS.

(52) Feed 1 (homogeneous mixture of):

(53) TABLE-US-00007 152.7 g deionized water 14.4 g Rhodafac ® RS610/A25, 3.0 g Disponil ® FES 993, 209.0 g styrene 196.9 g 2-ethylhexyl acrylate 18.2 g Sipomer ® PAM-200, 14.1 g methyl methacrylate, 133.3 g n-butyl methacrylate 22.4 g acetoacetoxyethyl methacrylate, 6.2 g acrylic acid

(54) The aqueous polymer dispersion obtained after filtration had a solids content of 50.0% by weight. The weight-average particle diameter was determined as 98 nm, the coagulate content as <0.1% by weight and the fine coagulate content as 467 μg/g of aqueous polymer dispersion. The pH of the aqueous polymer dispersion was determined as 5.1. The dispersion polymer had a glass transition temperature Tg of 14° C.

Comparative Example 8 (Comparative Dispersion V8)

(55) Production of comparative example 8 was carried out completely analogously to the production of example 1 with the exception that in feed 1 96.9 g instead of 196.9 g of styrene and 296.9 g instead of 196.9 g of 2-ethylhexyl acrylate were employed.

(56) The aqueous polymer dispersion obtained after filtration had a solids content of 49.5% by weight. The weight-average particle diameter was determined as 127 nm with a second fraction at 880 nm, the coagulate content as 1% by weight and the fine coagulate content as 8744 μg/g of aqueous polymer dispersion. The pH was determined as 4.2 at the end of the first polymerization stage and as 6.7 at the end of the second polymerization stage. The dispersion polymer had a glass transition temperature Tg.sup.1 of −32° C. and a glass transition temperature Tg.sup.2 of −8° C.

(57) Performance Testing

(58) For the performance testing a clear lacquer and a pigmented anticorrosion coating were produced from each of the obtained aqueous polymer dispersions of the examples and the comparative examples. To this end the polymer dispersions 1 to 6 and V5 to V8 were first diluted with deionized water to a solids content of 49.5% by weight.

(59) Production of the Clear Lacquers

(60) Production of the clear lacquers was carried out such that in each case 96.0 g of the aqueous polymer dispersions 1 to 6 and V5 to V8 diluted to 49.5% by weight were adjusted to a pH of 9.5 with a 50% by weight aqueous solution of dimethylethanolamine from Huntsman Corporation at room temperature with stirring and then in each case 3 g of the organic solvent Texanol® from Eastman Chemical and 1 g of the anticorrosion inhibitor CHE®-COAT-CI LNF A4 from C. H. Erbslöh KG were added and the mixture was mixed until homogeneous. The obtained clear lacquers are hereinbelow referred to as clear lacquer 1 to 6 and V5 to V8.

(61) Early Water Test

(62) The clear lacquers 1 to 6 and V5 to V8 to be tested were each applied to a surface of a 200×80 mm cleaned and grease-free, ungalvanized steel sheet with a box-type blade coater, wherein the gap size was chosen such that a dry layer thickness of 40 to 85 μm was obtained. The thus-coated steel sheets (referred to hereinbelow as steel sheets 1 to 6 and V5 to V8) were each dried for two hours at 23° C. and 50% relative atmospheric humidity in a climate controlled cabinet. Actual testing was then carried out such that the steel sheets 1 to 6 and V5 to V8 were placed vertically in a water bath filled with deionized water to a fill height of 15 cm for 24 hours at room temperature. The steel sheets 1 to 6 and V5 to V8 were then removed from the water bath, dabbed dry with a soft cotton cloth and the respective change in color tone between the area wetted with water and the unwetted area was assessed. The change in color tone was visually evaluated according to the following scale: 0 (no change) to 5 (clear change in color tone over whole area). The results obtained are reported in table 1 below.

(63) TABLE-US-00008 TABLE 1 Results of early water test Steel sheet Evaluation 1 0 2 0 3 0 4 1 5 1 6 0 V5 4 V6 2 V7 2 V8 3
Production of the Pigmented Anticorrosion Coatings

(64) 167.9 g of the aqueous polymer dispersions 1 to 6 and V5 to V8 diluted to 49.5% by weight were in each case admixed at room temperature with 1.5 g of the commercially available defoamer for coatings BYK® 022 (Byk GmbH; mixture of polysiloxanes and hydrophobic solids in polyglycol). Subsequently a Dispermat was used to add in each case 15.0 g of deionized water, 1.0 g of a 25% by weight aqueous ammonia solution, 1.5 g of Dispex® Ultra PA4570 (BASF SE; dispersing additive, based on modified polyacrylate) and 4.5 g of Dispex® CX 4231 (BASF SE; dispersing additive based on an ammonium salt of an organic acid copolymer in water). With stirring a mixture of 2.2 g of phenoxypropanol (film-forming assistant) and 2.2 g of benzine (boiling range 180° C. to 210° C.; film-forming assistant) was further incorporated. Subsequently 25.5 g of the hematite pigment Bayferrox® 130 M (Lanxess AG), 10.8 g of talc 20 M 2 (Luzenac; filler: magnesium silicate), 38.3 g of Litopone® L (Sachtleben, filler based on barium sulfate and zinc sulfide), and 24.6 g of Heucophos® ZMP (Heubach, anticorrosion pigment based on zinc phosphate) were added. Then a further 0.8 g of BYK® 022 and 1.1 g of a 1:1 mixture of water and corrosion inhibitor L 1 (C. H. Erbsloh KG) were added. The entire mixture was premixed for 10 minutes in a dissolver with a toothed disk (diameter 5 cm; 2000 revolutions per minute) and subsequently dispersed for 20 minutes with a twin Teflon disk (diameter 5 cm; 2300 revolutions per minute) and 200 g of glass pearls (diameter 3 mm). The glass pearls were then removed by sieving. Finally, the respective batches were admixed with 1.8 g of a 25% by weight aqueous ammonia solution and a mixture of 0.3 g of a 25% by weight aqueous solution of a commercially available urethane-based thickener (Rheovis® PU 1280, BASF SE) and 1.0 g of butylglycol (solvent) and the pH was optionally adjusted to 9.5 with 25% by weight aqueous ammonia solution. The obtained anticorrosion formulations 1 to 6 and V5 to V8 had a solids content of 61% by weight and a pigment/volume concentration of 23%. The obtained anticorrosion formulations were diluted to a viscosity of approximately 300 mPas (determined at room temperature using a Rotothinner 455N sphere from Sheen Instruments) with deionized water and the respective solids contents were determined.

(65) It should be noted in this context that the anticorrosion formulation V6 thickened immediately after production so that this formulation could not be used for coating a steel sheet.

(66) Salt Spray Test

(67) To test the anticorrosion properties a salt spray test according to DIN EN ISO 7253 (360 hour test duration) was performed using a 5% by weight aqueous sodium chloride solution. To this end the diluted anticorrosion formulations 1 to 6 and V5, V7 and V8 were each applied to one side of a 200×80 mm cleaned, ungalvanized steel sheet with a box-type blade coater, wherein the gap size was in each case chosen such that a dry layer thickness of 60 to 100 μm was obtained. The test sheets obtained after coating were stored and thus dried at 23° C. and 50% relative atmospheric humidity in a climate controlled cabinet for 6 days. The coated test sheets were then stored at a temperature of 50° C. for a further 24 hours. After cooling to room temperature to protect against corrosion the reverse sides of the respective test sheets were coated with a solvent-based coating and then dried at room temperature for 24 hours. Before the actual test the edges of the respective test sheets were taped-up with a plastic film. The respective test sheets were then scored down to the steel on the coated side with a scribe and sprayed with salt water for 360 hours. Evaluation of the obtained test sheets 1 to 6 and V5, V7 and V8 was carried out by optical comparison of the tested samples with the standards specified by DIN EN ISO 7253. The corrosion behavior of the individual test sheets was evaluated as follows with reference to subsurface corrosion around the score, surface corrosion and adhesion by means of the cross-cut test.

(68) Subsurface Corrosion Around Score (as Per DIN EN ISO 4628-8; 2013):

(69) Corrosion formed below the coatings proceeding from the sites of artificial damage. The values reported in table 2 indicate the maximum distance in millimeters of the thus formed iron oxide as measured from the scores. Before inspection, loose coatings around the scores were removed using adhesive tape. The lower the measured values, the better the assessment according to the invention.

(70) Surface Corrosion:

(71) Determination was carried out by visual determination of the fraction of the corroded surface area relative to the total surface area of the test sheets. The values reported in table 2 represent the percentage fraction of corroded surface areas. In this case, the lower the measured values, the better the assessment.

(72) Adhesion (Cross-Cut Test According to DIN EN ISO 2409):

(73) The adhesion of the anticorrosion coatings to the substrate was determined by means of the cross-cut test. To this end, after the salt spray test a grid composed of a plurality of cuts (line spacing 2 mm) was cut into the respective dabbed-dry anticorrosion coating, covered with adhesive tape and then the adhesive tape was removed. The appearance of the grid was assessed after removal of the adhesive tape. Scores of 0 to 5 were given according to the following scale:

(74) TABLE-US-00009 Gt 0 The edges of the cuts were completely smooth and none of the quadrants of the grid had flaked off. Gt 1 The coating had flaked off along the cut edges but the flaked-off area was not more than 15% of the cross-cut area. Gt 2 The flaked-off grid area was more than 15% but not more than 35%. Gt 3 Along the cut edges the coating had partially or completely flaked off in broad strips or some quadrants had partially or completely flaked off. Gt 4 The affected cross-cut area was more than 35% but not more than 65%. Gt 5 Any flaking that could be classified as more severe than Gt 4.

(75) The thus obtained results are likewise reported in table 2 below.

(76) TABLE-US-00010 TABLE 2 Results of salt spray test Test Subsurface corrosion Surface sheet around score [in mm] corrosion [in %] Cross-cut 1 5 <5 Gt 0 2 8 <5 Gt 1 3 6 <5 Gt 0 4 2 <5 Gt 0 5 9 5 Gt 1 6 7 <5 Gt 0 V5 20 15 Gt 2 V7 10 10 Gt 1 V8 15 20 Gt 5
Determining Film Hardness

(77) Film hardness was determined by the König pendulum damping test according to DIN EN ISO 1522. Determination was carried out such that the diluted anticorrosion formulations 1 to 6 and V5, V7 and V8 were each applied to one side of a 200×80 mm cleaned, ungalvanized steel sheet with a box-type blade coater, wherein the gap size was in each case chosen such that a dry layer thickness of 60 to 100 μm was obtained. The obtained coated test sheets were stored for 20 hours at 50° C. in a drying cabinet and subsequently cooled to room temperature. The König pendulum damping test according to DIN EN ISO 1522 was performed on the thus obtained coated steel sheets. The results obtained during testing of the steel sheets coated with the anticorrosion formulations 1 to 6 and V5, V7 and V8 are reported in table 3. The higher the number of pendulum strokes, the harder the coating.

(78) TABLE-US-00011 TABLE 3 Film hardness results Number of Steel sheet pendulum strokes 1 17 2 18 3 30 4 22 5 17 6 16 V5 15 V7 8 V8 5

(79) It is unambiguously apparent from the results of the performance testing that the coatings produced with the anticorrosion formulations produced with the polymer dispersions according to the invention exhibit markedly better values in respect of subsurface corrosion around the score, surface corrosion, cross-cut testing and film hardness than the anticorrosion formulations produced with the corresponding comparative dispersions.