TW201418386A - Fouling-reducing additives, process for production thereof and use thereof in coatings - Google Patents

Abstract

The present invention relates to a fouling-reducing additive containing at least (a) one modified or non-modified silica, silicate or silica gel having a median particle size d50 of 100-500 μ m, (b) one modified or non-modified silica, silicate or silica gel having a median particle size d50 of 20-70 μ m and (c) one modified or non-modified silica, silicate or silica gel having a median particle size d50 of < 20 μ m. The fouling-reducing additive according to the invention is produced by mixing. The fouling-reducing additive can be used in paints.

Description

Additive for reducing dirt, its manufacturing method and its use in coatings

The present invention relates to an additive for reducing soil, a method for its manufacture and its use in a coating.

In the context of the present invention, the term additive for reducing soil is used in place of the conventional term antifouling additive in order to establish that the effect of the additive according to the invention is completely from the point of release of the soil coated layer and the easy to clean coating. Based on physical effects, and without the need to remove biological agents or biologically active substances.

EP 2 281 855 A1 discloses an antifouling additive which acts according to the principle of chemical action, i.e. the mechanism of action for reducing fouling is based on the release (leaching) of the biocide from the coating, in particular a natural biocide, such as menthol.

Furthermore, additives for reducing soil are known from WO9729157A1, EP1570980A1, JP10025427A and JP09053612A, which are based on the principle of physical action, for example for the production of surfaces containing air. Paint surface. By using fine particles or fibers, a ternary boundary layer air-water-coating is formed which is said to have a beneficial effect on the adhesion properties of the surface. Disadvantageously: during the immersion in water in the case of moving objects such as boats, the air can only remain in the layer boundary layer for a short period of time, so that no long-term activity is provided according to this coating.

JP 08268377 A describes as an alternative to supplying air by means of a compressor which is less relevant for certain applications.

CN101792534A discloses micro- and nano-structured surfaces having antifouling activity, which are produced by a cast surface (mold). In this way, natural antifouling surfaces (such as shark skin) can ideally be replicated, depending on the principle of physical action. Although the antifouling activity of artificial surfaces has been proven, the basis of this technology has not been converted to industrial scale.

Furthermore, DE 10 2006 030 055 A1 discloses a nanostructured coating system based on nanoscale hydrophobic particles. However, these are not very stable under mechanical loading because the functionalized particle system cannot be firmly fixed in the binder and therefore does not provide long-term activity. Furthermore, surface topography is produced by unimodal nanoparticles which are not suitable for physical soil reduction in the context of the present invention.

Numerous scientific publications describe physical fouling reductions based on layered structured surfaces, such as, for example, "Surface modification approaches to control marine biofouling", Scardino, Advances in marine antifouling coatings and technology, 2009, Woodhead Corporation, 664-692 page. It is thus known that, with regard to the antifouling activity, the surface should be provided with structures of different size classes. Because of all kinds of living in the sea In the further sense of reducing the effect of fouling, it is impossible to achieve an antifouling effect using only one structure. Therefore, in order to protect against microorganisms, other structural sizes are required compared to microorganisms such as mites and algae. This size has changed from a few nanometers to hundreds of microns.

EP 1 591 509 A1 describes the creation of a lotus effect surface by ceramic micro-hollow beads, which in turn will be occupied by nanoparticles (for example aluminium oxide, aluminum oxyhyrate, titanium dioxide, zirconium dioxide) and in the application of conventional lotus effects (buildings) Improved service life in the case of walls, buildings, roofs.

Similarly, EP 1 283 077 A1 describes a depression and a high self-cleaning surface produced by particles, wherein the particles are provided with antimicrobial properties, ie active ingredients, in a manner that is not only physically active.

US20080241408A1 describes the creation of a lotus effect surface having a structure in the range of <500 nm, i.e., a liquid repellent surface, by using two colloidal particles of a size in the range of 15-2000 nm and 1-200 nm, respectively.

Additional functionality can be achieved by modifying the particles with a hydrocarbon such as an alkyl chain, a decane or a biocide (EP 1882722 A1).

Microstructured surfaces in accordance with natural patterns, in addition to the use of particles, can also be produced by using fibers oriented in a natural plant pattern (such as a water-distributed seed) or an animal pattern (such as a sea lion). WO2007108679A1 describes the use of μm fibers which are sprayed onto wet paint by electrostatic charge and thus produce a sea lion-like surface structure. It is known to those skilled in the art that this type of application is difficult to convert to industrial scale.

In addition, the structured surface can also be produced by polymer modification (Development and Testing of Hierarchically Wrinkled Coatings for Mavine Antifouling, Efimenko, Applied Materials & Interfaces, Vol. 1, No. 5, 1031-1040, 2009).

It is an object of the present invention to provide an additive for reducing soil which is incorporated into a coating material, which achieves the effect of reducing soiling according to a non-toxic physical action principle, and which can be manufactured on a commercial scale by a conventional method. In addition, the soil-reducing activity of the applied hardened coating should be possible, depending on any adhesive system having the concentration used and the optimum parameters known to those skilled in the art.

Another object of the present invention is to provide an additive for reducing soil which is substantially or completely biodegradable and/or biologically harmless.

Another object of the present invention is to provide an additive for reducing soil which ensures adequate protection against dirt not only during the voyage but also during the waiting time of contact or contact of the boat or other object with water, in particular sea water. .

Another object of the present invention is to provide an additive for reducing soil which, incorporated into a selected coating, ensures easier cleaning of the adhered soil. This easier cleaning is based on the fact that by using these additives, a microstructured surface is produced and the number of sticking points is reduced. Furthermore, the flow dynamics of the coating can be advantageously produced, which also leads to easier cleaning.

Biodegradability or biodegradability within the meaning of the present invention means the ability of organic chemicals to biodegrade, ie their ability to be destroyed by living organisms or their enzymes. Ideally, this chemical metabolism is completely mineralized, so the organic compounds decompose into inorganic substances such as carbon dioxide, oxygen and ammonia. Analytically, this process can be determined, for example, by specifying a half-life. If complete biodegradation is not possible in the sense defined above, it is determined that the additives used are not deleterious in the sense of the present invention. That is to say, the additive has no toxic or harmful effects on other organisms. Additives do not accumulate in water or only to a slight extent and are not harmful to the environment.

Environmentally harmful in the sense of the meaning of the invention means that the properties of a mixture of substances and substances in humans, animals, plants, biomes and their habitats, in particular soils, are permanently or indirectly damaged or irreversibly altered.

Within the meaning of the present invention, reducing the fouling means that the coating with the additive for reducing the fouling reduces the colonization of the fouling organism (i.e., micro-soil and giant fouling) compared to the same coating that does not contain the additive for reducing the fouling. Nature.

The invention relates to an additive for reducing dirt, which contains at least a) a modified or unmodified vermiculite, citrate or bismuth gel having a median particle diameter d50 of from 100 to 500 μm, preferably from 100 to 300 μm. b) a modified or unmodified vermiculite, citrate or bismuth gel having a median particle diameter d50 of 20-70 μm (preferably 20-50 μm) and c) A modified or unmodified vermiculite, citrate or bismuth gel having a median particle diameter d50 of <20 μm (preferably 10 nm to 10 μm).

The additive for reducing soil can be free of biological or biologically active substances. The vermiculite may be a precipitated and/or pyrolytic vermiculite. For example, precipitated or pyrolyzed vermiculite according to EP 1 398 301 A2, EP 1241135 A1, EP 1648824 A1, EP 0798348 A1, EP 0341383 A1 or EP 0922671 A1 can be used.

Precipitated or pyrolytic vermiculite and cerium gels have been used as a standard for additives in coatings (for example for rheology control or matting), thus ensuring easy blending and homogenization of additives according to methods known to those skilled in the art. Distributed in the coating without the need to complete the formulation of the recoating system.

The three vermiculite, citrate or strontium gels a)-c) can be mixed with each other in variable ratio. The mixing ratio and amount used in this case can have a considerable influence on the structure produced and thus have a considerable influence on the activity for reducing soil. Preferably, the mixing ratio (by mass) of vermiculite, citrate or strontium gel a):b):c) may be from 3:2:1 to 0.5:0.5:1. Particularly preferably, the mixing ratio of vermiculite, citrate or strontium gel a): b): c) (by mass basis) may be 1:1:1; 3:2:1 or 6:4: 5. Mixing ratios other than those specified may also prove to be advantageous depending on the system selected.

In a preferred embodiment of the invention, the vermiculite, citrate or sulfonium gel a)-c) can be used in a modified form. Modification can be carried out via surface modification or impregnation of the particles.

The method of surface modification can be any functionalization with decanes, polyoxins, fatty acids, carbon compounds, polymers, etc., which results in covalent bonds or physical bonds, for example according to solid particles and material systems. Van der Waals. However, it must be noted in this case that due to this functionalization, no antimicrobial properties are produced in the sense of biological action, but only modification of the surface properties (for example hydrophobicity) is achieved. The decanes used for surface modification, for example, the following decanes, alone or in mixtures: organodecanes (RO) ₃ Si (C _n H _2n+1 ) and (RO) ₃ Si (C _n H _{2n -1} ), wherein R is the same or different and is alkyl (such as methyl, ethyl, n-propyl, isopropyl or butyl) and n = 1-20, organodecane R' _x (RO) _y Si(C _n H _2n+1 ) and R′ _x (RO) _y Si(C _n H _2n-1 ), wherein R is the same or different and is an alkyl group (such as methyl, ethyl, n-propyl, iso) Propyl or butyl), R' is the same or different and is alkyl (such as methyl, ethyl, n-propyl, isopropyl, butyl or cycloalkyl and n = 1-20; x + y = 3, x = 1 or 2, y = 1 or 2, haloorganosin X ₃ Si (C _n H _2n+1 ) and X ₃ Si (C _n H _2n-1 ), wherein X = Cl or Br; =1-20, haloorganoxane X ₂ (R')Si(C _n H _2n+1 ) and X ₂ (R')Si(C _n H _2n-1 ), wherein X=Cl or Br, R' = alkyl (such as methyl, ethyl, n-propyl, isopropyl, butyl or cycloalkyl) and n = 1-20, haloorganoxane X(R') ₂ Si (C _n H _{2n+ 1)} and _{X (R ') 2 Si (} C n H 2n-1), where X = Cl or Br; R' is identical or different and are an alkyl group (such as methyl, ethyl, n-propyl, iso Group, a butyl group or a cycloalkyl group), and n = 1-20, organosilane type _{(RO) 3 Si (CH 2} ) m -R ", wherein R is the same or different and is an alkyl group (such as methyl, ethyl, , n-propyl, isopropyl or butyl), m = 0.1-20, R" = methyl, aryl (such as -C ₆ H ₅ or substituted phenyl), C ₄ F ₉ , OCF ₂ - _{CHF-CF 3, C 6 F} 13, OCF 2 CHF 2, S z - (CH 2) 3 Si (OR) 3, where ^{z = 1-10, SH, NR 1} R 2 R 3, where R ¹ = alkyl Or aryl; R ² =H, alkyl or aryl; R ³ =H, alkyl, aryl, benzyl, C ₂ H ₄ NR ⁴ R ⁵ , wherein R ⁴ =H or alkyl and R ⁵ = H or alkyl, organodecane (R') x (RO) _y Si(CH ₂ ) _m -R", wherein R is the same or different and is an alkyl group (such as methyl, ethyl, n-propyl) , isopropyl or butyl), R' is the same or different and is alkyl (such as methyl, ethyl, n-propyl, isopropyl, butyl or cycloalkyl), x + y = 3, x =1 or 2, y=1 or 2; m=0.1 to 20, R”=methyl, aryl (such as C ₆ H ₅ or substituted phenyl), C ₄ F ₉ , OCF ₂ -CHF-CF ₃ , C ₆ F ₁₃ , OCF ₂ CHF ₂ , S _z -(CH ₂ ) ₃ Si(OR) ₃ , wherein z=1-10, SH, NR ¹ R ² R ³ , wherein R ¹ = alkyl or aryl; R ² = H, alkyl or aryl; R ³ = H, alkyl, aryl, benzyl, C ₂ H ₄ NR ⁴ R ⁵ wherein R ⁴ = H or alkyl And R ⁵ =H or an alkyl group, a halogen organodecane X ₃ Si(CH ₂ ) _m -R ⁶ wherein X = Cl or Br, m = 0.1-20, R ⁶ = methyl, aryl (such as C ₆ H ₅ or substituted phenyl), C ₄ F ₉ , OCF ₂ -CHF-CF ₃ , C ₆ F ₁₃ , O-CF ₂ -CHF ₂ , SH or S _z -(CH ₂ ) ₃ Si(OR) ₃ , wherein z = 1-10 and R are the same or different and are alkyl (such as methyl, ethyl, n-propyl, isopropyl or butyl), haloorganodecane RX ₂ Si(CH ₂ ) _m R ⁶ X=Cl or Br, m=0.1-20, R is the same or different and is an alkyl group (such as methyl, ethyl, n-propyl, isopropyl or butyl), R ⁶ = methyl, aromatic group (such as C ₆ H ₅ or substituted phenyl _{of), C 4 F 9, OCF} 2 -CHF-CF 3, C 6 F 13, OCF 2 -CHF 2, SH or S _z - (CH _{2) 3} Si(OR) ₃ , wherein z=1−10, haloorganodecanes R ₂ XSi(CH ₂ ) _m R ⁶ X=Cl or Br, m=0.1-20, R is the same or different and is alkyl ( Such as methyl, ethyl, n-propyl, isopropyl or butyl), R ⁶ = methyl, aryl (such as C ₆ H ₅ or substituted phenyl) , C ₄ F ₉ , OCF ₂ -CHF-CF ₃ , C ₆ F ₁₃ , O-CF ₂ -CHF ₂ , SH or S _z -(CH ₂ ) ₃ Si(OR) ₃ , wherein z=1-10, a quinone alkane R ⁷ R ⁸ ₂ SiNHSiR ⁸ ₂ R ⁷ , wherein R ⁷ and R ⁸ are the same or not and are alkyl, vinyl or aryl, cyclic polyoxyalkylenes D3, D4, D5 and a homologue, wherein D3, D4 and D5 represent a cyclic polyoxyalkylene having 3, 4 or 5 units of -O-Si(CH ₃ ) ₂ , such as octamethylcyclotetraoxane (D4) The following types of polyoxyalkylenes or polyoxygenated oils, Wherein R ^{9 =} alkyl, R ^{10 =} substituted or unsubstituted alkyl, aryl or H

R ^{11 =} substituted or unsubstituted alkyl or aryl

R ¹² = substituted or unsubstituted alkyl, aryl or H

_{Y = CH 3, H, C} v H 2v + 1, where _{v = 1-20, Si (CH 3} ) 3, Si (CH 3) 2 H, Si (CH 3) 2 OH, Si (CH 3) 2 (OCH ₃ ) or Si(CH ₃ ) ₂ (C _v H _2v+1 )

Wherein R ¹⁰ or R ¹¹ or R ¹² may be (CH ₂ ) _v -NH ₂ and v=1-20, m'=0, 1, 2, 3, ... 100 000, n'=0, 1. 2, 3, ... 100 000, u' = 0, 1, 2, 3, ... 100 000.

Preferably, as the surface modifier, the following materials may be used: octyltrimethoxydecane, octyltriethoxydecane, hexamethyldiazepine, 3-methylpropenyloxypropyltrimethoxy Baseline, 3-methylpropenyloxypropyltriethoxydecane, cetyltrimethoxydecane, cetyltriethoxydecane, dimethylpolyoxane, hexafluorohexyltrimethyl Oxydecane, tridecafluorooctyl-trimethoxydecane or tridecafluorooctyltriethoxydecane.

Particularly preferably, hexamethyldioxane, octyl-triethoxydecane or dimethylpolyoxane can be used.

The modification can be carried out, for example, by using polyoxyxylene oil, polyethylene glycol, polysaccharides, block polymers, caprolactones, lactide and glycolide polymers, polyanhydrides, polyesters. It is achieved by impregnation with hydroxybutyric acid, polyphosphorus, polyphosphate, polyvinyl alcohol, polyvinyl acetate, alginate, gelatin, agar or pectin. The modified vermiculite, citrate or strontium gel can be incorporated into the coating system in a manner similar to pure vermiculite, citrate or strontium gel, where additional functionality can be produced which has the effect of reducing fouling or Modify the processing properties of the coating. In the case of modified vermiculite, citrate or strontium gel, almost completely The embedded binder can be carried out in such a way that the surface of the vermiculite/citrate or the gel is not free to be exposed and the surface functionality present cannot be activated.

In a preferred embodiment of the invention, the vermiculite, citrate or strontium gel a-c may be a mixture of non-modified and modified vermiculite. In this case, one, two or three of the three vermiculite, citrate or strontium gel a-c are present in a modified form.

In addition to the median diameter, the vermiculite and citrate used may have a fineness value of from 10 to 45 μm (preferably from 20 to 43 μm), and/or from 50 to 350 g/l (preferably from 50 to 300 g/l). The compact density, and/or the oil absorption value from 180 to 360 g/100 g and/or the DBP value from 200 to 450 g/100 g (preferably 320 to 400 g/100 g), and/or from 100 to 600 m ² /g ( Preferably from 200 to 550 m ² /g, particularly preferably from 300 to 550 m ² /g, very particularly preferably from 350 to 500 m ² /g), and/or from 6 to 14 ml/g (0.0042-414 MPa, 140°) The total pore volume. Very particularly preferably, the vermiculite and citrate have a combination of a plurality of the above physicochemical properties and, more preferably, all of the above properties are combined.

Depending on the concentration, microstructuring can occur by introducing microstructured particles into the coating formulation on the surface coated with such coating formulations, which can affect biofilm growth and bulk soiling.

In order to be able to achieve sufficient enhancement of the coating system, the BET surface area is important.

The additive for reducing soil according to the present invention may be a powder (preferably a free flowing powder). This means that the fluidity of the product as measured using the effluent funnel as indicated in DIN 53492 preferably has a value of one. Use according to the invention The additives for reducing dirt can therefore be handled and transported particularly well.

The invention further relates to a process for the manufacture of an additive for reducing soil according to the invention, characterized in that the following is mixed: a modified or unmodified ruthenium having a particle size of from 100 to 500 μm, preferably from 100 to 300 μm. a stone, citrate or bismuth gel a), a modified or unmodified vermiculite, citrate or bismuth gel having a particle size of 20-70 μm (preferably 20-50 μm) and a A modified or unmodified vermiculite, citrate or bismuth gel having a particle size of <20 μm (preferably 10 nm to 10 μm) c). The vermiculite, citrate or strontium gel a-c may be modified. This modification can be carried out via surface modification or impregnation of the particles.

Mixing can be, for example, in a kneader, paddle dryer, drum mixer, vertical mixer, paddle mixer, Schugi mixer, cement mixer, Gericke continuous mixer, Eirich mixer, and/or silo mixing In the device.

The temperature in the mixing unit can be between 5 ° C and 120 ° C.

Mixing can be carried out under an air atmosphere. The additive for reducing soil according to the present invention can be used in a coating system (preferred coating).

A coating system comprising an additive for reducing soil according to the present invention can be applied to the surface of an object to protect the surface of an object in contact with or in contact with water, particularly seawater.

The invention further relates to a coating comprising at least a) a modified or unmodified vermiculite, citrate or bismuth having a median particle diameter d50 of from 100 to 500 μm, preferably from 100 to 300 μm. Glue, b) a medium particle diameter d50 of 20-70 μm (preferably 20-50) Μm) modified or unmodified vermiculite, citrate or strontium gel and c) a modified or unmodified vermiculite having a median diameter d50 of <20 μm (preferably 10 nm-10 μm) , citrate or bismuth gel.

The coating according to the invention may be free of or in addition to biological agents.

The modified or unmodified vermiculite, silicate or bismuth gel a)-c) can be dispersed in the finished coating formulation in any desired order.

The invention further relates to a coating characterized in that it contains an additive for reducing soil according to the invention.

The coating according to the invention may contain from 1 to 40% by weight, preferably from 10 to 20% by weight, based on the coating, of additives for reducing soiling.

The additive for reducing soil can be dispersed in the finished coating formulation with moderate shear and the coating can then be applied as a final coating using conventional methods. Rollers and sprayers can be used for this purpose. In addition to the particles used, the mixing ratio, the particle concentration and the choice of coating formulation, the application technique can also have an effect on the resulting structure.

It has further been found that the activation of the surface of the vermiculite/citrate or ruthenium gel which is modified by hydrolysis upon contact with water and the activation of the surface active groups present therewith. For this purpose, vermiculite, citrate or strontium gels may be modified or impregnated, for example with a water soluble polymer, and then incorporated into the coating system by such methods. When in contact with water (i.e., during the desired period of use), the water soluble polymer will dissolve as water diffuses into the coating network. The water soluble polymer used can be biodegradable and environmentally friendly. As the polymer detaches from the surface of the particles, at the same time, the coating on the particles is separated, thereby exposing the surface of the particles. The particles remain painted The matrix is sufficiently surrounded in such a way that the vermiculite, citrate or bismuth gel is not exposed to the coating system and cannot exit the coating matrix. By this mechanism, it is possible to distribute the functionality in the coating in a targeted manner, and so when pure vermiculite/citrate or cerium gel particles are used in the hydrophobic coating system, for example hydrophilic spots can be in the hydrophobic matrix. produce. These alternating surfaces will in turn exhibit particularly good soil-reducing properties. Furthermore, by this mechanism, the functionality of the modified vermiculite/citrate or cerium gel particles may be exposed to the surface in a targeted manner after incorporation into the coating matrix.

Compared to the reference system without the addition of structuring elements, the coatings produced in this manner exhibited a reduction in fouling in laboratory biological experiments and field experiments of the test organism Ps. Atlantica. Another advantage produced by the use of the additives is the increase in mechanical strength and the possibility of adjusting rheology. All of the objects exposed to the risk of biofouling can be coated using the additive for reducing soil according to the present invention. These are in particular yachts, commercial vessels, buildings and facilities submerged in water, such as, for example, landing platforms, dock walls, oil rigs, etc., channel signs, other buoys or measuring probes.

Measurement methods Analysis of physicochemical properties of vermiculite, citrate or strontium gel Determination of DBP value:

The DBP absorption (DBP value) for measuring the absorption capacity of the porous particles is measured according to DIN standard 53601 as follows: 12.50 g of a powdery or bead type support material having a moisture content of 0-10% (optionally, in a drying cabinet) The moisture content was adjusted to dry at 105 ° C) and placed in the kneading machine chamber of the Brabender absorption meter "E" (article number 279061) (the output filter without the wetting torque sensor). In the case of granules, a sieve fraction of 3.15 to 1 mm (stainless steel screen from Retsch) was used (by gently squeezing the granules through a sieve with a pore width of 3.15 mm). Dibutyl phthalate was added dropwise to the mixture via a "Dosimat Brabender T 90/50" at a rate of 4 ml/min using a fixing (rotation speed of the kneader blade 125 rpm) at room temperature. Use only low power requirements and add in accordance with the reference digital display. When the measurement is toward the end point, the mixture becomes a paste, which is a sharp increase in power demand. At the display of 600 values (torque of 0.6 Nm), both the kneader and the DBP meter are turned off by electrical contact. The synchronous motor for the DBP feed is connected to the digital counter in a readable DBP consumption (ml). DBP absorption is reported in units without decimal places [g/(100g)] and is calculated according to the following formula: Where DBP=DBP absorption (in g/(100g))

V = DBP consumed (in ml)

D = density of DBP (in g/ml) (1.047 g/ml at 20 ° C)

E = starting weight of meteorite (in g)

K = correction value according to the moisture correction table (in g/(100g))

The DBP absorber is defined for the anhydrous dry support material. When used For wet support materials (especially precipitated vermiculite or tantalum gel), the correction value K should be considered for the calculation of DBP absorption. This value can be determined according to the following calibration table, for example, a water content of 5.8% of the support material indicates an increase in DBP absorption of 33 g/(100 g). The moisture of the support material was measured according to the method described below in "Measurement of Moisture or Loss on Drying".

Table: Dibutyl phthalate absorption - anhydrous - moisture correction table

Determination of oil absorption value

The oil absorption value is determined using linseed oil as specified in DIN EN ISO 787-5.

Determination of moisture or loss on drying

The moisture or loss on drying (TV) of the support material was measured after drying at 105 ° C for 2 hours as indicated in ISO 787-2. This loss on drying is mainly composed of moisture.

step

10 g of powder bead or granulated material was weighed (accurate to the accuracy of 0.1 mg) in a dry weighing bottle (3 cm in diameter and 3 cm in height) with a frosted glass cover (initial weight E). The sample was dried at 105 ± 2 ° C for 2 hours in a drying cabinet. The weighing bottle was then sealed and cooled to room temperature in a drying cabinet using silicone as the drying medium. The weighing bottle/glass beaker was weighed (accurate to 0.1 mg) on a precision balance to determine the final weight A. The moisture content (TV) was determined from the following formula: in terms of percentage: TV = (1-A/E) * 100, where A = final weight, in g and E = initial weight, in g.

Median particle size d ₅₀

The particle distribution of the product system according to the invention was determined by means of a laser diffraction method using a laser diffraction (Horiba, LA-920). In order to determine the particle size of the powder, a dispersion having a weight fraction of about 1% by weight of SiO _{2 was} prepared by mixing the powder into water.

Immediately after dispersion, the particle size distribution was measured on a secondary sample using a dispersion using a laser diffraction meter (Horiba LA-920). For measurement, a relative refractive index of 1.09 is required. All measurements were taken at room temperature. The particle size distribution and associated factors such as, for example, the median particle size d ₅₀ are automatically calculated by the instrument and are shown graphically. Pay attention to the instructions in the operating instructions.

Determination of BET surface area

Determination of powdered vermiculite, vermiculite with approximately spherical particles or granular vermiculite using a TRISTAR 3000 (Micromeritics) instrument, as indicated in ISO 5794-1/Annex D, using a multipoint assay as specified in DIN-ISO 9277 Nitrogen specific surface area (hereinafter referred to as BET surface area).

Determination of tamping density

The tamping density is determined as specified in DIN EN ISO 787-11.

Determination of total pore volume

The total pore volume was determined by a mercury intrusion porosimeter method. The method is based on Hg intrusion (contact angle at surface tensions of 480 mN/m and 140°) as indicated in DIN 66133, using an Autopore IV 9500 instrument from Micromeritics.

The vermiculite was pressure treated prior to measurement. For this purpose, a manual hydraulic press (Order No. 15011 from Specac Ltd., River House, 97 Cray Avenue, Orpington, Kent BR5 4HE, U.K.) was used. In this case, 250 mg of vermiculite was weighed into a (pellet die) having an inner diameter of 13 mm (from Specac Ltd.), and was loaded with 1 ton according to the display. The load is maintained for 5 s and is optionally further controlled. The sample was then expanded and dried in a circulating air drying cabinet at 105 ± 2 ° C for 4 h.

The vermiculite is weighed (accurate to 0.001 g) in a type 10 penetrometer, and for the good reproducibility of the measurement, "the volume used (stem volume) Weigh the used ("that is, the percentage of Hg consumed by the penetrator" is 20% to 40%. Then slowly weigh the penetrator to 50μm Hg and maintain at this pressure. 5 min. Operate the Autopore instrument using Software IV version 1.05 according to the operating instructions. Calibrate each measurement with a blank measurement of the penetrator. The measurement range is 0.0042-414 MPa.

Determination of fineness value

The fineness value is determined as indicated in DIN EN 21524.

Determination of fluidity

Fluidity was evaluated using glass discharge vessels of different discharge diameters. Use markers 1-7 for rating:

It is reported that the powder just flows out of the measuring container without stopping.

The following examples are intended to illustrate the invention, but are not intended to limit the invention.

Example 1: Coating with modified vermiculite

The vermiculite to be modified (Sipernat ^® 22, Sipernat ^® 50, Sipernat ^® 50S) was fed to the mixer (Somakon laboratory mixer) in each case according to the initial weight in Table 1 and the mixing operation was started (250 rpm) , 25 ° C). From the aqueous solution (40% by weight), it was slowly added dropwise (3 minutes) to the modified polymer (polyethylene glycol from Aldrich 10,000). After another 15 minutes, the mixing operation was terminated. The particles remain fluid. Then, a drying step (drying cabinet, 80 ° C, 24 h) was carried out. Finally, the particles were washed with an organic solvent (ethanol), filtered and dried again (vacuum drying cabinet, 80 mbar, 50 ° C, 24 h).

Table 1 lists the initial weights for individual modifications of the vermiculite type comprising polyethylene glycol 10,000. Sipernat ^® 22, Sipernat ^® 50 and of Silica Sipernat ^® 50S from Evonik Industries of.

In the modified vermiculite types 1-3 listed in Table 1, the soil-reducing additive according to the present invention is a modified vermiculite 1-3 by weight ratio of 6:4:5 by using a drum mixer. (modified Sipernat ^® 22: modified Sipernat ^® 50: modified Sipernat ^® 50S) was prepared by mixing at 25 ° C for 30 min.

Thereafter, a coating was produced according to Table 2 (composition of the coating). First of all, The first component was produced with a dissolver (Dispermat, diameter: 80 mm, 2000 rpm, 30 min).

In the second step, a dispersing hardener (DYNASYLAN ^® AMEO) and an additive for reducing dirt (Dispermat, diameter: 40 mm, 1000 rpm, 10 min) were used. The paint was applied to the substrate to be coated using a spray gun (Sata Jet 90 pistol, inlet pressure 3 bar, 2 spray operations, nozzle diameter 1.4 mm). As a test surface, a roughened PVC board (20 x 20 cm for field experiments; 7.5 x 2.5 cm for laboratory experiments) was used. After 8 h, the coating according to the invention hardens and is ready for use.

Sampling was performed in a field experiment under dynamic conditions in the North Sea (Hooksiel) (sample carousel, 8h rotation, 8h rest, about 5 knots). then The evaluation is carried out according to the weighing, that is, the difference in quality and the comparison of surface dirt. The coating system comprising the soil-reducing additive according to the present invention reduces the quality of the soil by more than 30% compared to the reference coating without the additive for reducing soil according to the present invention.

Example 2: Coating with a mixture of 3 vermiculite

The additive for reducing soil according to the present invention was produced from the amount of the vermiculite type described in Table 3. Mixing was carried out in a tumble mixer at 25 ° C for 30 min.

A coating was then made as in Example 1.

Results of the field experiment:

Field experiments were performed as in Example 1. The coating system according to the present invention comprising an additive for reducing soil reduces the quality of the soil by more than 40% compared to the reference coating without the additive for reducing soil according to the present invention.

Results of laboratory experiments:

For laboratory analysis of the activity of reducing fouling, laboratory experiments were conducted. In the experimental structures developed specifically for this purpose, the activity of the formulations produced was tested on a laboratory scale. As a test microorganism, marine bacteria Ps. Atlantica and marine medium (pH=7.8; artificial seawater (for example, marine broth supplied by Carl Roth) were used. The coating according to the present invention was exposed to a test medium (artificial seawater with test microorganisms) 24h to colonization. FilmTracer ^TM and by using the live / dead assay kit ^® biofilm viability of live or dead microbial counts compared to no staining for the additive for reducing fouling of a reference system according to fouling of the surface coating of the present invention Analysis: It was found that the coating system (soil 57%) containing the additive for reducing dirt according to the present invention was reduced by >40% compared to the coating (stain 100%) without additives for reducing dirt. .

Shape:

The surface topography of the surface of the coating according to the invention produced was measured using a profiler (Hommelwerke, Turbo Rauheit V6.14). Table 4 shows the measurement compared to the coating systems according to the present invention containing only two kinds of Silica (5 wt% Sipernat ^® 22 + 5 wt% Sipernat ^® 50) of the coating mixture containing one Silica (5 wt% Sipernat ^® 22 Roughness profile heights Rt, Rz and roughness roughness Ra of the coatings without coatings.

Example 3: Coating containing vermiculite (comparative coating)

A coating was prepared as described in Example 1, in which Sipernat ^® 820A (d ₅₀ = 7.5 μm) was used as an additive. Sipernat ^® 820A is Al citrate from Evonik Industries.

Results of laboratory experiments:

Laboratory experiments were performed as described in Example 2. It was observed that using a coating system containing additives (Sipernat ^® 820A) (scale 15%), microbial growth increased by >50% compared to coatings (100% soil) without additives for reducing dirt. The use of a vermiculite is not suitable as an additive for reducing dirt.

Claims (13)

An additive for reducing soil, comprising at least a) a modified or unmodified vermiculite, citrate or strontium gel having a median particle diameter d50 of from 100 to 500 μm, b) a medium-sized granule Modified or unmodified vermiculite, citrate or strontium gel having a diameter d50 of 20-70 μm and c) a modified or unmodified vermiculite or tannic acid having a median diameter d50 of <20 μm Salt or gelatin. An additive for reducing scale according to the scope of claim 1 wherein the mixing ratio of vermiculite, citrate or strontium gel (by mass) is a): b): c) 3: 2:1 To 0.5:0.5:1. An additive for reducing soil according to claim 1 or 2, wherein a), b) and c) are precipitated or pyrolytic vermiculite. An additive for reducing fouling according to item 3 of the patent application, wherein at least one of the precipitated or pyrolytic vermiculite is surface-modified. An additive for reducing soil according to item 4 of the patent application, wherein the surface-modified precipitated or pyrolytic vermiculite is surface-modified with decane. An additive for reducing fouling according to item 3 of the patent application, wherein at least one of the precipitated or pyrolytic vermiculite is impregnated. An additive for reducing soil according to item 6 of the patent application, wherein the impregnated precipitated or pyrolytic vermiculite is impregnated with polyethylene glycol. A method for preparing an additive for reducing scale according to item 1 of the patent application, characterized in that the following are mixed: A modified or unmodified vermiculite, citrate or bismuth gel having a particle size of 100-500 μm, a modified or unmodified vermiculite or tannic acid having a particle size of 20-70 μm Salt or bismuth gel b) and a modified or unmodified vermiculite, citrate or bismuth gel c) having a particle size of <20 μm. A use of an additive for reducing fouling in a coating system according to claims 1-7 of the patent application. The use of an additive for reducing scale according to claim 9 of the scope of the patent application, wherein the coating system is a coating. A coating comprising at least a) a modified or unmodified vermiculite, citrate or strontium gel having a median particle size d50 of from 100 to 500 μm, b) a median particle size d50 Modified or unmodified vermiculite, citrate or strontium gel of 20-70 μm and c) a modified or unmodified vermiculite, citrate or salt having a median diameter d50 of <20 μm or矽 gel. A coating comprising the additive for reducing soil according to any one of claims 1 to 7. A coating according to claim 12, wherein the mixture contains 2 to 30% by weight of an additive for reducing soil.