HK1245314B - Improved coating systems, use thereof for coating components and thus coated components for agricultural and construction machines - Google Patents

Description

Improved coating system, its use for coating parts, and parts coated thereby for agricultural machinery and construction machinery

The present invention relates to improved coating materials based on RMA systems crosslinked by means of classical Michael addition. The invention also relates to coatings producible therefrom and coated components, in particular components for agricultural and construction machinery, such as vehicle bodies, tools or attachments.

Coating materials that crosslink using the Michael addition reaction are known. The coatings produced therefrom have high weathering stability and chemical resistance. The rapid curing of these coating materials is achieved by using high catalyst contents, but this results in a significantly shortened processing time and pot life of the coating material.

Fast curing is particularly advantageous when coating or painting large parts, such as car body components. However, due to the size and shape of the surface, coating the entire part requires a relatively long time, so the coating material used must have a long pot life and a long open time. Hereinafter, pot life refers to the time interval between mixing all the components of the coating material and the point at which the crosslinking reaction in the coating material has progressed to the point at which the coating material can no longer be processed. Hereinafter, open time refers to the time interval during which the applied coating material film can be corrected without impairing the leveling properties.

During the application of the coating material, the area that has been coated must additionally be able to absorb the overspray that occurs when painting adjacent areas, without, for example, surface defects occurring due to poor leveling. hereinafter, overspray refers to the material loss of the coating material caused when spraying. The material loss may be caused by the prior spraying due to the unfavorable orientation of the spray gun to the workpiece or in the case of a strong interruption of the workpiece, such as a grid. Overspray can also occur due to droplets of coating material flowing down from the side in front of the workpiece surface. Overspray absorption is the property that the applied coating material absorbs the material from the overspray to retain the desired smooth surface of the film or layer.

After applying a film or layer of coating material, it is desirable for the coating to dry or cure as quickly as possible. Forced drying at elevated temperatures is often not possible with large components, as this would require correspondingly large ovens. Therefore, rapid drying at room temperature is particularly desirable, especially when coating or painting very large components.

EP 2374836 A1 discloses binder systems crosslinking by Michael addition (hereinafter referred to as RMA systems) that have a favorable ratio of pot life to drying time. These binder systems have a long pot life and a short drying time, even at room temperature. For this purpose, reference is expressly made to EP 2374836 A1, which is incorporated into this specification. A disadvantage of known RMA systems is that the coating materials and coatings produced therefrom do not exhibit the necessary and customary properties.

The object of the present invention is therefore to provide improved coating materials, coatings and coating systems based on RMA systems, which are suitable in particular for coating large components such as body parts and tools of agricultural and construction machines.

This object is achieved by a coating material for producing a coating according to the main claim. Further embodiments are disclosed in the independent and dependent claims as well as in the description.

The coating material according to the invention comprises an RMA system having one or more C-H acidic compounds A, one or more vinyl-like carbonyl compounds B and one or more catalysts C. Furthermore, it comprises at least one or more light stabilizers, one or more pot life extenders, one or more open time extenders, one or more inorganic and/or organic pigments and one or more corrosion inhibitors.

In the following text, the term "light stabilizer" is understood to mean additives and adjuvants which protect coatings from UV light, in particular prevent or at least significantly delay the decomposition of polymers caused by UV radiation. The term "pot life extender" is understood to mean additives and adjuvants which, as a component of the mixed coating material, delay the curing of the coating material before application. They evaporate during application and thus do not affect, in particular do not delay, the curing of the applied coating material. The term "open time extender" is understood to mean additives and adjuvants which remain in the coating material even after application and delay its curing to form a coating. The term "corrosion inhibitor" is understood to mean additives and adjuvants which prevent or at least delay the corrosion of the metal at the interface between the metal substrate and the coating.

The coating material according to the present invention comprises at least

10 to 70, preferably 15 to 60, particularly preferably 20 to 55% by weight of CH-acidic compounds A,

4 to 40, preferably 8 to 35, particularly preferably 10 to 30% by weight of a vinyl-like carbonyl compound B,

0.1 to 15, preferably 0.2 to 10, particularly preferably 0.3 to 5% by weight of a latently basic catalyst C,

0.00001 to 10, preferably 0.5 to 5, particularly preferably 1 to 3% by weight of light stabilizers,

0.00001 to 20, preferably 0.01 to 10, particularly preferably 0.1 to 5% by weight of an open time extender,

0.00001 to 20, preferably 0.01 to 15, particularly preferably 0.1 to 10% by weight of a pot life extending agent,

0.1 to 65, preferably 5 to 55, particularly preferably 8 to 40% by weight of inorganic and/or organic pigments,

0.1 to 40, preferably 1 to 35, particularly preferably 3 to 30% by weight of corrosion inhibitors,

The amounts stated therein are each based on the total amount of coating material.

According to the invention, compounds A and B are used in a substance ratio of A:B of 0.5:1 to 2:1, preferably 0.75:1 to 1.6:1, particularly preferably 0.9:1 to 1.3:1, very particularly preferably 0.95:1 to 1.1:1, the substance amounts being based on the acidic protons of compound A and on the vinyl-like carbonyl group of compound B.

According to the invention, catalyst C and compound A are used in a C:A molar ratio of 0.8:1 to 2.5:1, preferably 1.1:1 to 1.9:1, particularly preferably 1.3:1 to 1.7:1, wherein the molar ratios are based on the cation X ⁺ of catalyst C and the acidic protons of compound A.

Suitable CH acidic compounds A are compounds of the general formula I

in,

R is hydrogen, alkyl or aryl, and

Y and Y' are alkyl, aralkyl, aryl, alkoxy or amino, preferably primary amino, and Y and Y' may be the same or different.

Furthermore, the -C(=O)-Y and/or -C(=O)-Y' groups of formula I may be replaced by CN- or aryl groups.

According to the present invention, malonates, acetoacetates or mixtures thereof are preferably used. Particularly preferred are malonates with oligomeric and polymeric substituents, for example based on polyesters, polyurethanes, polyacrylates, epoxy resins, polyamides or polycarbonates. Particularly preferred are malonates with oligomeric and polymeric substituents based on polyesters, polyurethanes and/or polycarbonates. The acetoacetates used preferably contain oligomeric and polymeric substituents, for example based on polyols, polyvinyl alcohols, epoxy resins, hydroxyl-functionalized polyethers, polyesters or polyacrylates. Particularly preferred are acetoacetates with oligomeric and polymeric substituents based on polyesters and/or polyacrylates. Very particularly preferred compounds are selected from malonates with oligomeric and polymeric substituents based on polyesters, which are obtained by reacting at least malonic acid, dimethyl malonate and/or diethyl malonate with hexahydrophthalic acid and/or its anhydride and neopentyl glycol; and acetoacetates with oligomeric and polymeric substituents based on polyesters, which are obtained by reacting at least acetoacetic acid, methyl acetoacetate and/or ethyl acetoacetate with hexahydrophthalic acid and/or its anhydride and neopentyl glycol.

Suitable vinyl-like carbonyl compounds B are, for example, acrylates and/or maleates, in particular unsaturated acryloyl-functionalized compounds. According to the invention, acrylates composed of compounds containing 1 to 20 carbon atoms and at least 2, preferably 2 to 6, hydroxyl groups are preferred. Also preferred according to the invention are polyesters obtained by reacting maleic acid, fumaric acid and/or itaconic acid or their anhydrides with di- or polyhydroxy compounds which may contain monohydroxy compounds or carboxyl compounds. Further preferred are resins such as polyesters, polyurethanes, polyethers and/or alkyd resins, which accordingly contain activated unsaturated groups, such as urethane acrylates, polyether acrylates, multifunctional polyacrylates, polyalkyl maleates and polyacrylates obtained by reacting acrylic acid with epoxy resins. Particularly preferred according to the invention are butanediol diacrylate, hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, di(trimethylolpropane) tetraacrylate and dipentaerythritol hexaacrylate, as well as dipropylene glycol diacrylate and tripropylene glycol diacrylate.

Suitable latently basic compounds of catalyst C are, for example, substituted carbonates of the formula II:

in

R is hydrogen, alkyl or aralkyl (Ar-R) or a polymer,

X ⁺ is an alkali metal cation or an alkaline earth metal cation, especially lithium, sodium or potassium, or a quaternary ammonium salt or a quaternary phosphonium salt of formula (R') ₄ Y ⁺ ,

Wherein Y is nitrogen or phosphorus,

R' is the same or different and is hydrogen, alkyl, aryl (Aral-) or aralkyl or a polymer,

And among them

R and R' can form a ring structure

or

R and R' may be polymers.

According to the present invention, R is preferably alkyl or aralkyl, particularly preferably has the alkyl of 1 to 4 carbon atom.In addition, carbonate radical group and cation X ⁺ also can be present in the molecule with corresponding structure.In addition, R ' is preferably alkyl, particularly preferably has the alkyl of 1 to 4 carbon atom (particularly preferably has 3 to 4 carbon atoms).According to the present invention, preferably use sal monium carbonate and/or phosphonium carbonate.Suitable sal monium carbonate is for example methyl carbonate tetrahexyl ammonium, tetrahexyl ammonium bicarbonate, methyl carbonate tetradecyl trihexyl ammonium, methyl carbonate tetradecyl ammonium, methyl carbonate tetrabutyl ammonium, ethyl carbonate tetrabutyl ammonium, tetrabutyl ammonium bicarbonate, methyl carbonate tetrapropyl ammonium, ethyl carbonate tetrapropyl ammonium, tetrapropyl ammonium bicarbonate, methyl carbonate benzyl trimethyl ammonium, methyl carbonate trihexyl methyl ammonium or methyl carbonate trioctyl methyl ammonium.Particularly preferably use methyl carbonate tetrabutyl ammonium, ethyl carbonate tetrabutyl ammonium, tetrabutyl ammonium bicarbonate, methyl carbonate tetrapropyl ammonium, ethyl carbonate tetrapropyl ammonium, tetrapropyl ammonium bicarbonate and composition thereof.

Suitable light stabilizers include free radical scavengers such as aliphatic sterically hindered amines, for example, based on substituted 2,2,6,6-tetramethylpiperidines; UV absorbers such as 2-hydroxyphenylbenzotriazoles, 2-hydroxybenzophenones, 2-hydroxyphenyltriazines, or oxalic acid anilides; and quenchers such as organonickel compounds and peroxide decomposers such as thioethers or phosphites. Free radical scavengers such as aliphatic sterically hindered amines based on substituted 2,2,6,6-tetramethylpiperidines and/or UV absorbers such as 2-hydroxyphenylbenzotriazoles, 2-hydroxybenzophenones, 2-hydroxyphenyltriazines, and oxalic acid anilides are preferably used. Substituted 2,2,6,6-tetramethylpiperidines, 2-hydroxyphenyltriazines, 2-hydroxybenzophenones, and mixtures thereof are particularly preferred.

Suitable pot life extenders are short-chain alcohols having a volatility value of less than 35, preferably less than 20. Particularly suitable are alcohols having up to 6, preferably up to 4, particularly preferably up to 3 carbon atoms. Thus, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and mixtures thereof can be used according to the invention.

Suitable open time extenders are basic NH-functional compounds having a _pKa value between 4 and 14. Preferred are succinimides, 1,2,4-triazoles, 1,2,3-benzotriazoles, 5,5-diphenylhydantoins, hydantoins, (RS)-3-ethyl-3-methylpyrrolidine-2,5-dione, and mixtures thereof. Particularly preferred are succinimides, 1,2,4-triazoles, 1,2,3-benzotriazoles, and mixtures thereof.

Suitable inorganic pigments are, for example, titanium dioxide, iron oxide, chromium oxide, chromium titanate, bismuth vanadate, cobalt blue and carbon black. Preferred inorganic pigments are titanium dioxide, iron oxide and carbon black. Suitable organic pigments are, for example, pigment yellow 151, pigment yellow 213, pigment yellow 83, pigment orange 67, pigment orange 62, pigment orange 36, pigment red 170, pigment violet 19, pigment violet 23, pigment blue 15:3, pigment blue 15:6, pigment green 7. Preferred pigments are pigment yellow 151, pigment orange 67, pigment red 170, pigment violet 19, pigment blue 15:3, pigment green 7.

Suitable corrosion inhibitors include tannin derivatives, alkaline sulfonates, nitrocarboxylates such as carbamates, and zinc salts of organic nitrogenous acids, such as zinc nitroisophthalate or zinc cyanuric acid. Other suitable corrosion inhibitors include anticorrosive pigments such as iron mica, aluminum pigments, or talc, as well as active pigments that electrochemically passivate metal surfaces, such as phosphates, borates, silicates, molybdates, or chromates. According to the present invention, active pigments are preferred, for example, those containing zinc, aluminum, magnesium, zirconium, and strontium cations, as well as mixtures thereof. Particularly preferred are aluminum magnesium phosphates, aluminum zinc phosphates, and aluminum strontium phosphates.

In a further embodiment of the invention, further additives and auxiliaries such as dispersing additives, fillers and/or matting agents may be added to the coating material in order to improve the desired properties of the coating material and/or the coating.

The coating material according to the invention may contain up to 25%, preferably 0.00001 to 8%, particularly preferably 0.00001 to 5% by weight of a dispersing additive, the amounts stated being based on the total amount of the coating material. Suitable dispersing additives are, for example, high molecular weight block copolymers with pigment-affinity groups, highly branched polyesters, and acrylate-polyester copolymers with pigment-affinity groups. Preferred dispersing additives are high molecular weight block copolymers with pigment-affinity groups.

The coating material according to the invention may further contain up to 60%, preferably 0.00001 to 40%, particularly preferably 10 to 30% by weight of fillers, the amounts stated being based on the total amount of the coating material. Suitable fillers are, for example, carbonates such as chalk, limestone powder, calcite, precipitated calcium carbonate, dolomite, or barium carbonate, sulfates such as barite, barium sulfate, or calcium sulfate, fibers fused from glass or basalt, glass powder, glass beads, and slag. Barium sulfate and/or calcium carbonate are preferably used as fillers.

The coating material according to the invention may further contain up to 30%, preferably 0.00001 to 20%, particularly preferably 0.00001 to 10%, by weight of a matting agent, the amounts stated being based on the total amount of the coating material. The term "matting agent" is understood to mean additives and auxiliaries that reduce the gloss of a coating or create a matte finish. Matting agents create the necessary surface structure in the coating without impairing other characteristics and properties. Suitable matting agents include, for example, micronized amorphous silica, such as silica gel or precipitated silica, micronized and precipitated waxes, such as polyethylene wax, polypropylene wax, polyamide wax, or PTFE wax, and micronized polymers, such as urea-formaldehyde resins. Preferred matting agents include micronized and precipitated polyethylene wax, polypropylene wax, polyamide wax, PTFE wax, and micronized urea-formaldehyde resin.

In another embodiment according to the invention, the coating material further comprises up to 50%, preferably 0.00001 to 30%, particularly preferably 0.00001 to 20% by weight of an aprotic solvent, the amounts stated being based on the total amount of the coating material. The term "aprotic solvent" is hereinafter understood to mean a solvent whose molecules do not contain ionizable protons. Suitable aprotic solvents are, for example, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, ketones, esters, ethers, ether esters, in particular ethyl acetate, butyl acetate, acetone, n-butyl ketone, methyl isobutyl ketone, methoxypropyl acetate and dimethyl sulfoxide. Preferred solvents are ethyl acetate, butyl acetate, acetone, n-butyl ketone, methyl isobutyl ketone, methoxypropyl acetate and mixtures thereof.

The compound used as the catalyst C according to the present invention is a potential base because the carbonate according to formula II is in equilibrium with its dissociation product, carbon dioxide, and the corresponding hydroxide base or alkoxy base. As long as carbon dioxide cannot escape from the system, the equilibrium is on the carbonate side. Only when carbon dioxide is removed and a sufficient amount of base is present does crosslinking begin by Michael addition. When the coating material according to the present invention is stored in a closed container, carbon dioxide cannot escape therefrom, and the coating material according to the present invention can be formulated in principle as a single-component system. However, if the individual components of the coating material according to the present invention are formulated in a multi-component system, storage stability can be improved. Therefore, for example, the catalyst component comprising catalyst C can be mixed with the binder component comprising C₁₂ acidic compound A and vinyl-like carbonyl compound B within a short period of time before processing.

According to the present invention, C₂O₂ acidic compound A and vinyl-like carbonyl compound B may be included in the binder component together with the used light stabilizer, open time extender and pot life extender. The binder component may also include pigment, filler, anticorrosive agent, other other additives and solvent. Catalyst C and optional other solvents and pot life extender may be included in the catalyst component. In a preferred embodiment, C₂O₂ acidic compound A may be present in the first binder component, vinyl-like carbonyl compound B may be present in the second binder component and catalyst C may be present in the catalyst component. In such a three-component system, C₂O₂ acidic compound A is preferably included in the first binder component together with the open time extender and light stabilizer. Optionally, the first binder component may also include pigment, filler and anticorrosive agent and other additives. The second binder component preferably includes vinyl-like carbonyl compound B. In addition, the second binder component may also include pigment, filler, anticorrosive agent and other additives. Catalyst C is included in the catalyst component. In addition, the catalyst component may include solvent and pot life extender.

It is known that the addition of further ingredients conventional for coating production reduces the storage stability of RMA systems. The coating materials according to the invention with specially selected light stabilizers, open time extenders, pot life extenders, pigments, corrosion inhibitors, dispersing additives, functional fillers, matting agents, and aprotic solvents have unexpectedly high storage stability compared to previously known coating materials based on RMA systems.

Furthermore, the properties of coatings produced from coating materials based on RMA systems differ from those of coating materials based on conventional binders, such as epoxy resins or polyurethanes, and are strongly negatively affected by the presence of other components of the coating material. It has surprisingly been shown that the coating materials according to the invention produce coatings having the properties necessary for use in parts of construction and agricultural machinery, in particular mechanical stability and corrosion resistance, even at high layer thicknesses.

In a particularly preferred embodiment, the coating material according to the invention comprises at least:

10 to 70, preferably 15 to 60, particularly preferably 20 to 55% by weight of C₄-acidic compounds A, for example malonic esters with oligomeric or polymeric substituents based on polyesters, obtained by reaction of at least malonic acid, dimethyl malonate and/or diethyl malonate with hexahydrophthalic acid and/or its anhydride and neopentyl glycol; and acetoacetic esters with oligomeric and polymeric substituents based on polyesters, obtained by reaction of at least acetoacetic acid, methyl acetoacetate and/or ethyl acetoacetate with hexahydrophthalic acid and/or its anhydride and neopentyl glycol,

4 to 40, preferably 8 to 35, particularly preferably 10 to 30% by weight of a vinyl-like carbonyl compound B, for example butanediol diacrylate, hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, di(trimethylolpropane) tetraacrylate and/or dipentaerythritol hexaacrylate,

0.1 to 15, preferably 0.2 to 10, particularly preferably 0.3 to 5% by weight of a catalyst C, for example tetrabutylammonium methylcarbonate, tetrabutylammonium ethylcarbonate, tetrabutylammonium hydrogen carbonate, tetrapropylammonium methylcarbonate, tetrapropylammonium ethylcarbonate, tetrapropylammonium hydrogen carbonate and mixtures thereof,

0.00001 to 10, preferably 0.5 to 5, particularly preferably 1 to 3% by weight of light stabilizers, for example substituted 2,2,6,6-tetramethylpiperidines, 2-hydroxyphenyltriazines, 2-hydroxybenzophenones and mixtures thereof,

0.00001 to 20, preferably 0.01 to 10, particularly preferably 0.1 to 5% by weight of open time extenders, for example succinimides, 1,2,4-triazoles, 1,2,3-benzotriazoles and mixtures thereof,

0.00001 to 20, preferably 0.01 to 15, particularly preferably 0.1 to 10% by weight of a pot life extender, for example methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and mixtures thereof,

0.00001 to 70, preferably 0.01 to 65, particularly preferably 0.1 to 40% by weight of inorganic and/or organic pigments, for example titanium dioxide, iron oxides, carbon black, Pigment Yellow 151, Pigment Orange 67, Pigment Red 170, Pigment Violet 19, Pigment Blue 15:3, Pigment Green 7 and mixtures thereof,

0.1 to 40, preferably 1 to 35, particularly preferably 3 to 30% by weight of corrosion inhibitors, for example aluminum magnesium phosphates, aluminum zinc phosphates and aluminum strontium phosphates,

0 to 25, preferably 0.00001 to 8, particularly preferably 0.00001 to 5% by weight of dispersing additives, for example high molecular weight block copolymers having pigment-affinity groups,

0 to 25, preferably 0.00001 to 15, particularly preferably 0.5 to 10, very particularly preferably 8 to 15% by weight of matting agents, for example micronized and precipitated polyethylene waxes, polypropylene waxes, polyamide waxes, PTFE waxes and micronized urea-formaldehyde resins and mixtures thereof,

0 to 60, preferably 0.00001 to 40, particularly preferably 0.00001 to 30% by weight of functional fillers, for example barium sulfate and/or calcium carbonate, and

0 to 50, preferably 0.00001 to 40, particularly preferably 0.00001 to 30% by weight of aprotic solvents, for example ethyl acetate, butyl acetate, acetone, n-butyl ketone, methyl isobutyl ketone, methoxypropyl acetate and mixtures thereof,

The stated amounts are in each case based on the total amount of coating material.

The coating materials and coatings according to the invention surprisingly have significantly higher storage stability than previously known RMA coating materials and RMA coatings. They also exhibit improved drying behavior. Furthermore, coatings obtained from the coating materials according to the invention have improved light stability, in particular, less yellowing and higher gloss retention.

The coating materials according to the present invention have a pot life of greater than or equal to 1 hour, preferably greater than or equal to 2 hours, particularly preferably between 2 and 4 hours. Typically, the pot life is determined by the flow time from the flow cup. The end of the pot life is determined as the point in time at which the flow time shows a value twice the start flow time. The test method is described in detail below in the examples. In addition, the coating materials according to the present invention show an open time of greater than or equal to 15 minutes, preferably greater than 20 minutes, particularly preferably greater than or equal to 25 minutes. In addition to the long pot life and open time, the coating materials according to the present invention unexpectedly show an unusually wide climate window in which they can be processed without damage. They are processable, for example, at temperatures of up to 45°C and at relative humidity of up to 99%. In addition, they show long overspray absorption, for example within a time interval of greater than 25 minutes.

Unlike conventionally used polyurethane-based coating materials, the coating material according to the present invention has a significantly shortened drying time. In a preferred embodiment, the coating material according to the present invention is used to prepare a coating on a substrate such as metal, plastic or fiber composite material. Particularly suitable are metals such as steel and iron alloys, aluminum and aluminum alloys. The surface of the component to be coated can be provided with a primer, such as conventional primers based on epoxy resin or polyurethane known to those skilled in the art. In addition, they can be pretreated as is conventional and familiar to those skilled in the art. Preferred pretreatments are iron phosphating, zinc phosphating, conversion layers based on manganese compounds, zirconium compounds and silicon compounds, sandblasting, galvanizing or electrophoretic dip coating. Particularly preferred pretreatments are conversion layers based on manganese compounds, zirconium compounds and silicon compounds. The coatings according to the present invention also exhibit good adhesion to the pretreated substrates. They also have a high corrosion protection effect.

The coatings according to the invention exhibit a visually flawless surface even at high layer thicknesses. They can have a dry layer thickness of between 80 and 150 μm. The coating materials according to the invention can be applied over a wide range of layer thicknesses without impairing the surface quality of the coating. The coating materials and coatings according to the invention are therefore relatively insensitive to the thickness of the covering layer that may occur during application, for example, due to unfavorable substrate geometries.

Due to the properties of the coating materials according to the invention, they can be used in particular for producing single-coat paints. They are also suitable for coating large parts, in particular for coating large-surface parts made of iron, such as parts of the bodies of construction and agricultural machinery.

The present invention also relates to a method for coating a component. The method according to the invention comprises the following steps: (a) applying the coating material according to the invention to the surface of a substrate, and (b) curing the applied coating material at a temperature of 5 to 50° C., preferably 15 to 40° C., particularly preferably 20 to 35° C., for 0.5 to 12 hours, preferably 0.5 to 6 hours, particularly preferably 0.5 to 4 hours.

The coating material according to the invention has an above-average solids content and therefore contains a low proportion of volatile organic substances, such as solvents. The solids content is defined as the mass fraction of the coating material remaining as a residue after evaporation at 105°C for 30 minutes. Essentially, the solids typically consist of binder, non-volatile additives, pigments, and fillers. The solids content of the coating material according to the invention is between 65 and 95%, preferably between 70 and 90%, and particularly preferably between 75 and 85% by weight, based on the total weight of the coating material.

Conventional spraying methods often produce rough, matte surfaces when coating materials with a high solids content are applied. In contrast, the coating materials according to the invention surprisingly produce high-quality surfaces even when applied by means of hydraulic, very high-pressure spraying (airless), airless spraying with air support (air mix), and pneumatic or compressed air spraying. All spraying methods can also be used with electrostatic assistance.

In another embodiment of the method, all components of the coating material used are mixed before application. The mixing can be carried out manually or by machine.

Since the coating materials according to the invention cure at room temperature, they are particularly suitable for coating large parts, for example, in the construction of agricultural and construction machinery. They can be used, for example, to coat body parts, roofs, doors, chassis linings, lattice bars, booms, grippers, buckets, sliver cutters or plowshares.

Example

The coating material was prepared according to standard paint technology known and familiar to those skilled in the art.The catalyst solution used in Example Formulation 1 was prepared by adding 42.8 g diethyl carbonate and 26.1 g isopropyl alcohol to a solution of 17.1 g tetrabutylammonium hydroxide in 14 g water.

Example Formulation 1: Topcoat

To evaluate the storage stability of the coating materials, the pot life and drying time of Example Formulation 1 were determined. Samples were tested after 1 day of storage at 23°C, 28 days of storage at 40°C, and 1 year of storage at 20 to 23°C or used to produce coatings.

Determination of Pot Life: The pot life is determined using a flow cup. In this method, a defined volume of liquid is filled into a cup with a defined nozzle at its bottom. The coating material flows through the nozzle, and the flow time is measured from the time the liquid jet exits until it is interrupted. All preparations and measurements are carried out at a temperature of 23°C. First, all components of the coating material are mixed and the flow time of the mixture is immediately measured (initial flow time). The measurement is repeated at regular intervals. The end of the pot life is reached when the flow time is twice the initial flow time.

Determination of Drying Time: To determine the drying time, a drying recorder (drying time measuring instrument from BYK Gardener) is used. The coating material to be tested is evenly applied to a glass strip using a film puller. The glass strip is then placed in a line recorder. A needle is then placed on the coating and pulled across the drying film at a defined, constant speed. This produces a characteristic drying profile of the coating, with individual time segments indicating different curing states: leveling or open time, initial marks, film tearing, and surface marks. Curing of the coating material begins at the end of the open time, i.e., at the point at which scratches left by the needle remain visible in the applied film. It ends at the surface marks, i.e., at the point at which the needle no longer leaves visible marks in the applied film.

To evaluate the storage stability of the coating materials, the quality of coatings produced from various stored coating materials of Example Formulation 1 was also tested. Gloss and corrosion protection were measured. Samples were used to produce coatings after storage for one day at 23°C, 28 days at 40°C, and one year at 20 to 23°C. To produce the test specimens, Example Formulation 1 was applied to pretreated steel panels using a cup spray gun and cured at room temperature. For precuring, the steel panels were provided with a silane conversion layer.

Determination of Surface Gloss: The gloss of the coating surface was measured as a reflectometer value. The reflectometer value of a sample is defined as the ratio of the light beam reflected in the mirror direction by the sample surface and a glass surface with a refractive index of 1.567. The measurement value was determined at an angle of 60° using a conventional reflectometer.

Determination of Corrosion Protection: To evaluate corrosion protection, a salt spray test is performed. The coating of the specimen is cut crosswise down to the metal surface. The specimen is then exposed to a salt spray consisting of a 5% salt solution with a pH between 6.5 and 7.2 in a spray chamber at 35 ± 2°C for 500 hours. The specimen is then rinsed with clean water and conditioned at room temperature for 1 hour. The damage beneath the surface layer is evaluated. To do this, any loose parts of the coating are carefully removed at the cut. The widest area of the detachment is determined and reported in millimeters.

Table: Storage stability of Example Formula 1

store 1 day, 23°C 28 days, 40℃ 1 year, 20-23℃ Applicable period 3h 3h 3h Opening hours 20min 21min 22min Surface trace end point 247 minutes 238min 241min Glossiness 89 90 88 Shedding width 0.5-2.5mm 1-2.5mm 1-2mm

As shown in the table above, the coating material according to the invention has a high storage stability. After prolonged storage at elevated temperatures, the coating material itself does not show a deterioration in its processability. The coatings thus prepared do not show any impairment in their properties either.

Claims (20)

1. A coating material for preparing a coating, having at least the following properties: -20 to 55% by weight of one or more CH acidic compounds A, -10 to 30% by weight of one or more vinyl-like carbonyl compounds B, -0.1 to 15% by weight of one or more potentially basic catalysts C, -0.00001 to 10% by weight of one or more light stabilizers, -0.00001 to 20% by weight of one or more open time prolonging agents, -0.00001 to 20% by weight of one or more pot life extenders, -0.00001 to 70% by weight of one or more inorganic and/or organic pigments, and -0.1 to 40% by weight of one or more corrosion inhibitors, Based on the total amount of coating material; Wherein, the CH acidic compound A is a compound of the following formula: in R is hydrogen, alkyl, or aryl. Y is alkyl, aralkyl, aryl, alkoxy, or amino, and Y' is alkyl, aralkyl, aryl, alkoxy, or amino; The vinyl-like carbonyl compound B is an acrylate and/or maleate; The catalyst C is one or more substituted carbonates of the following formula. in R is a hydrogen, alkyl, aralkyl, or polymer group. X ⁺ is an alkali metal or alkaline earth metal cation, or a quaternary ammonium salt or quaternary phosphonium salt of formula (R') _4Y ⁺ . in Y represents nitrogen or phosphorus. R' may be the same or different, and may be hydrogen, alkyl, aryl, or aralkyl or a polymer. Furthermore, R and R' form a ring structure or are polymers; The light stabilizer is selected from free radical scavengers, UV absorbers, quenchers, and peroxide decomposers; The pot life extender is selected from alcohols having up to 6 carbon atoms and a volatility of less than 35; The open time prolonging agent is selected from basic NH functional compounds having a _pKa value between 4 and 14; The corrosion inhibitor is selected from tannin derivatives, alkaline sulfonates, nitrocarboxylates, zinc salts of organic nitrogen-containing acids, corrosion-resistant pigments, and reactive pigments. 2. The coating material according to claim 1, wherein the pigment is selected from titanium dioxide, iron oxide, chromium oxide, chromium titanate, bismuth vanadate, cobalt blue, carbon black, pigment yellow 151, pigment yellow 213, pigment yellow 83, pigment orange 67, pigment orange 62, pigment orange 36, pigment red 170, pigment purple 19, pigment purple 23, pigment blue 15:3, pigment blue 15:6, and pigment green 7. 3. The coating material according to claim 1 or 2, characterized in that the coating material further comprises up to 25% by weight of one or more dispersing additives. 4. The coating material according to claim 3, wherein the dispersing additive is selected from high molecular weight block copolymers with pigment affinity groups, highly branched polyesters, and acrylate-polyester copolymers with pigment affinity groups. 5. The coating material according to claim 1, characterized in that the coating material further comprises up to 60% by weight of one or more fillers. 6. The coating material according to claim 5, wherein the filler is selected from carbonates, sulfates, silicates and silicon dioxide. 7. The coating material according to claim 1, wherein the coating material further comprises up to 50% by weight of one or more aprotic solvents. 8. The coating material according to claim 7, wherein the aprotic solvent is selected from aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, ketones, esters, ethers, ether esters and dimethyl sulfoxide. 9. The coating material according to claim 7, wherein the aprotic solvent is selected from ethyl acetate, butyl acetate, acetone, n-butyl ketone, methyl isobutyl ketone, and methoxypropyl acetate. 10. The coating material according to claim 1, wherein the coating material further comprises up to 10% by weight of one or more matting agents. 11. The coating material according to claim 10, wherein the matting agent is selected from micronized amorphous silica, micronized wax, precipitated wax, and micronized polymer. 12. Use of the coating material according to any one of claims 1 to 11, for preparing a single-layer coating system. 13. The use according to claim 12, characterized in that the coating material is used to prepare a topcoat for parts of construction machinery and agricultural machinery. 14. A method for coating parts, comprising the steps of: (a) applying a coating material according to any one of claims 1 to 12 onto a substrate, and (b) curing the applied layer at a temperature between 5 and 50°C for a period of 0.5 to 12 hours. 15. The method according to claim 14, wherein the coating material is applied in step (a) by means of a hydraulic or pneumatic spraying method. 16. The method according to claim 14 or 15, characterized in that the components of the coating material are mixed prior to step (a). 17. The method according to claim 14, wherein in step (a), the coating material is applied to the pretreated substrate. 18. A component having a coating prepared from a coating material according to any one of claims 1 to 11. 19. The component according to claim 18, wherein it is a component of construction machinery or agricultural machinery. 20. The component according to claim 18, wherein it is a vehicle body component or a tool component.