EP1417040B2 - Aqueous functional coating material and integrated method for production of coloured or effect-generating multi-layer coatings - Google Patents

Abstract

A wet-on-wet process for producing multicoat color and/or effect coating systems is disclosed. The process involves using aqueous functional coating materials comprising (A) at least one crosslinkable binder, (B) at least one separate, water-soluble and/or -dispersible crosslinking system which independently effects partial or complete crosslinking in and/or on the matrix of the wet, drying and/or dried films (2) of the aqueous functional coating materials before the binders (A) crosslink completely; and (C) at least one pigment.

Description

The present invention relates to a novel integrated wet-on-wet process for producing multicoat color and / or effect coatings which comprise at least one functional layer and at least one color and / or effect solid-color topcoat or alternatively at least one color and / or effect basecoat and contain at least one clearcoat. In addition, the present invention relates to novel aqueous functional coating materials for the production of multicoat color and / or effect paint systems.

Integrated wet-on-wet processes are coating processes in which at least two different coating materials are applied to one another in at least two layers, the lower layer or the lower layers merely being dried but not completely crosslinked, after which the layers are cured together

1. (1) appliziert man wäßrige Funktions-Beschichtungsstoffe auf grundierte oder ungrundierte Substrate, wonach man
2. (2) die resultierenden Schichten der wäßrigen Funktions-Beschichtungsstoffe, ohne sie vollständig zu härten, trocknet,
3. (3) beschichtet man die getrockneten Schicht (2) mit Wasserbasislacken, wonach man
4. (4) die resultierenden Wasserbasislackschichten (3), ohne sie vollständig zu härten, mit Klarlacken beschichtet, wonach man
5. (5) die Schichten (2), (3) und (4) gemeinsam härtet, wodurch die Funktionsschichten, die farb- und/oder effektgebenden Basislackierungen und die Klarlackierungen resultieren.

Integrated wet-on-wet processes for producing multicoat color and / or effect paint systems which comprise at least one functional layer and at least one color and / or effect solid-color topcoat or alternatively at least one color and / or effect basecoat and at least one clearcoat known. In these integrated procedures

1. (1) applied aqueous functional coating materials on primed or ungrounded substrates, after which
2. (2) drying the resulting layers of the aqueous functional coating materials without fully curing them,
3. (3) coat the dried layer (2) with waterborne basecoats followed by
4. (4) the resulting aqueous basecoat films (3) are coated with clearcoats without curing completely, followed by
5. (5) co-curing layers (2), (3) and (4), thereby resulting in the functional layers, the color and / or effect basecoats and the clearcoats.

By way of example, the German patent application DE 44 38 504 A1 directed.

The aqueous functional coating materials used in this case are physically curable and contain as binder a water-dilutable polyurethane resin having an acid number of 10 to 60 and a number average molecular weight of 4,000 to 25,000. The polyurethane resin can be prepared by aa) a polyester and / or polyether polyol having a number average molecular weight of from 400 to 5,000 or a mixture of such polyester and / or polyether polyols, bb) a polyisocyanate or a mixture of polyisocyanates, cc) a compound, which has at least one isocyanate-reactive group and at least one group capable of forming anions in the molecule, or a mixture of such compounds and optionally dd) an organic compound containing hydroxyl and / or amino groups having a molecular weight of 40 to 400 or a mixture of such Compounds are reacted with each other and the resulting reaction product is at least partially neutralized. The aqueous functional coating materials further contain pigments and / or fillers, wherein the ratio of binder to pigment is between 0.5: 1 and 1.5: 1. In addition, they may contain Aminoplastharze or polyisocyanates in minor amounts.

The known aqueous functional coating materials allow the production of particularly thin surfacer finishes, antistonechip primers or functional layers, without the loss of stone chip resistance or deterioration of the coverage of the unevenness of the primed substrate occur. The known wet-in-wet process is therefore economically and ecologically particularly favorable.

A disadvantage is that the known wet-in-wet process is limited to the use of a specific type of polyurethane and therefore offers no alternatives in this respect. Nevertheless one is because of the numerous economic, ecological and technical advantages, which from the DE 44 38 504 A1 offer known aqueous functional coating materials and the wet-in-wet process made possible hereby, strives to replace the usual and known so-called Einbrennfüller by the aqueous functional coating materials.

However, this substitution is not readily possible, because in the production of color and / or effect multicoat systems according to the DE 44 38 504 A1 frequently an effect and / or hue shift compared to the color and / or effect multi-layer coatings occurs, in their preparation one and the same aqueous basecoat on baked surfacer coatings (see, for example, the German patent application DE 199 30 552 A1 ) and cured thereon. This also prevents the use of one and the same aqueous basecoat in the two processes in one operation.

1. (A) auf eine mit einem wäßrigen Funktions-Beschichtungsstoff (i) beschichtete Substratoberfläche ein Wasserbasislack (ii), der als filmbildendes Mittel eine wäßrige Polymerdispersion enthält, aufgebracht,
2. (B) auf die in Stufe (A) erhaltene Schicht ein geeigneter Klarlack aufgebracht und
3. (C) die Schicht aus dem wäßrigen Funktions-Beschichtungsstoff (i) und die Schicht aus dem Wasserbasislack (ii) zusammen mit der Klarlackschicht eingebrannt,

wobei der Wasserbasislack (ii) eine wäßrige Polymerdispersion enthält, enthaltend

• (x) ein (Meth)Acrylatcopolymerisat auf Basis von 30 bis 60 Gew.% C₁-C₈-Alkyl(meth)acrylat- Monomeren, 30 bis 60 Gew.-% vinylaromatischen Monomeren und 0,5 bis 10 Gew.-% (Meth)acrylsäure und
• (y) einen nicht- assoziativ wirkenden Verdicker, der ein (Meth)Acrylatcopolymerisat auf (C₁-C₆)-Basis von Alkyl(meth)acrylat und (Meth)acrylsäure enthält.

Another integrated wet-on-wet process is known from the European patent application EP 0 871 552 A1 known. In this known integrated method is

1. (A) on a substrate surface coated with an aqueous functional coating material (i), a water-based lacquer (ii) which contains an aqueous polymer dispersion as a film-forming agent,
2. (B) a suitable clearcoat is applied to the layer obtained in step (A), and
3. (C) the layer of the aqueous functional coating material (i) and the layer of the aqueous basecoat (ii) baked together with the clearcoat layer,

wherein the waterborne basecoat (ii) contains an aqueous polymer dispersion containing

• (x) a (meth) acrylate copolymer based on 30 to 60% by weight of C ₁ -C ₈ -alkyl (meth) acrylate monomers, 30 to 60% by weight of vinylaromatic monomers and 0.5 to 10% by weight (Meth) acrylic acid and
• (y) contains a non-associative thickener, the acrylate is a (meth) acrylate copolymer to (C ₁ -C ₆₎ based on alkyl (meth) acrylate and (meth) acrylic acid.

The color and / or effect multicoat paint systems produced by these integrated processes can be repaired very well, and the composition of the functional coating materials (i) is also not materially limited. However, this does not apply to waterborne basecoats (ii), which are necessarily aqueous dispersions of (meth) acrylate copolymers based on components (x) and (y). Only this ensures that it is also possible to use clearcoats based on powder slurry clearcoats for the production of the multicoat paint systems without causing cracking ("mud cracking")

There is therefore a need for a wet-on-wet process which has the advantages of the prior art, without showing its disadvantages and which makes it possible to substitute the Einbrennfüller without great material, apparatus and procedural effort without this an effect and / or hue shift occurs in the water-based paints.

Aqueous functional coating materials containing at least one saturated, unsaturated and / or ionically and / or nonionically stabilized polyurethane grafted with olefinically unsaturated compounds as binders and pigments are known from the German patent applications DE 199 14 896 A1 . DE 199 53 445 A1 . DE 199 53 203 A1 or DE 199 53 446 A1 They can be cured thermally or thermally and with actinic radiation. The thermal curing can be carried out by self-crosslinking or external crosslinking.

DE 199 14 896 A1 It was the object of the invention to provide novel polyurethane dispersions which have no or only a very low tendency to form coagulum.

DE 199 53 446 A1 It was an object of the present invention to provide novel olefinically unsaturated hydrophilic or hydrophobic polyurethanes which have a particularly high grafting activity and can be obtained in a simple manner. It was also the object of the invention to provide new graft copolymers based on the new polyurethanes.

The patent applications DE 199 53 445 A1 and DE 199 53 2 03 A1 was essentially the object of providing aqueous and non-aqueous self-crosslinking functional coating materials, adhesives and sealants based on polyurethane with very good performance properties. In particular, the self-crosslinking functional coating materials, especially the aqueous self-setting functional coating materials, especially the setbstvernetzenden waterborne basecoats, in their processing in wet-on-wet process even when using powder clearcoat slurries no cracking (mud cracking) or digester or Cause needle sticks. The new functional coating materials should show a very good storage stability, excellent application properties, such as a very good flow and a very low Läufemeigung even at high film thicknesses. The multicoat paint systems produced herewith are said to have an outstanding overall optical impression as well as a high resistance to chemicals, yellowing and weathering. Last but not least, no delamination of the layers after the water jet test should occur any more. All these advantages are to be achieved without an increase in the emission of organic compounds must be taken into account.

The aqueous functional coating materials of DE 199 53 445 A1 . DE 199 53 203 A1 or DE 199 53 446 A1 can also be used as a filler. Preferably, however, they are used as water-based paints. Whether and, if so, to what extent the known aqueous functional coating materials as fillers are capable of substituting conventional and known stoving fillers in the context of a wet-on-wet process without an effect and / or hue shift occurring not known. In addition, the known aqueous functional coating materials do not contain a separate, water-soluble and / or -dispersible crosslinking system, which in and / or on the matrix of wet, drying and / or dried layers of the aqueous functional coating materials for themselves partially or completely crosslinked before the layers completely crosslink completely. The patent applications can be found no evidence that could stimulate the expert to enforce the aqueous functional coating materials such a system.

From the German patent applications DE 199 04 317 A1 and DE 198 55 125 A1 aqueous multicomponent systems based on hydroxyl-containing polyurethanes and polyisocyanates are known. The aqueous multicomponent systems may contain radiation-curable binders, reactive diluents and photoinitiators. Thus, there are two separate networking systems next to each other. The aqueous multicomponent systems can also be used as fillers. However, the polyurethanes and the polyisocyanates begin to crosslink immediately after the application of the aqueous multicomponent systems because of their high reactivity, so that the curing with actinic radiation can not be carried out so that it is substantially completed before the complete thermal curing of the matrix of layers , Both injury mechanisms therefore run in parallel, or the curing with actinic radiation is carried out after the thermal curing

The German patent application DE 199 04 317 A1 It was the object of the invention to provide aqueous multicomponent systems which, especially during prolonged storage, are attacked and destroyed by microorganisms to a lesser extent or not at all.

The German patent application DE 198 155 125 A1 It was an object of the invention to provide aqueous multicomponent systems which are easy to prepare, homogeneous, easy to handle, low in solvents, safe to cook, splash-proof and stable in forced drying and which provide matt coatings which have no surface defects and gray haze, but are weather-stable and resistant to gasoline.

Accordingly, those skilled in the art were unable to find any indications of using two different crosslinking systems side by side in an aqueous polyurethane-based filler in order to prevent effect and / or color shade shift of the waterborne basecoats when replacing conventional baking finishes with the aqueous polyurethane-based fillers.

The thermal crosslinking of functional coating materials by the complementary keto groups and hydrazide groups is known per se. The use of these complementary reactive functional groups in aqueous functional coating materials based on polyurethanes is not described in the abovementioned German patent applications.

The object of the present invention is to provide a novel wet-on-wet process for the production of multicoat color and / or effect paint systems which has the economic, technical and ecological advantages of the German patent application DE 44 38 504 A1 or the European patent application EP 0 871 552 A1 has known method and which makes it possible to substitute Einbrennfüller without great material, apparatus and procedural effort, without this an effect and / or hue shift occurs in the water-based paints.

In addition, it was the object of the present invention to provide a novel aqueous functional coating material which is outstandingly suitable for the production of multicoat color and / or effect coatings, in particular for the production of functional layers, fillers, antistonechip primers, solid-color topcoats and basecoats Functional layers, can be used. Above all, however, the new aqueous functional coating material should be suitable for the new wet-on-wet process.

• (1) wäßrige Funktions-Beschichtungsstoffe auf grundierte oder ungrundierte Substrat appliziert, wonach man
• (2) die resultierenden Schichten der wäßrigen Funktions-Beschichtungsstoffe, ohne sie vollständig zu härten, trocknet,
• (3) die getrockneten Schichten (2) der wäßrigen Funktions-Beschichtungsstoffe mit wäßrigen Unidecklacken beschichtet, wonach man
• (4) die Schichten (2) und (3) gemeinsam härtet, wodurch die Funktionsschichten und die Unidecklackierungen resultieren;
  oder alternativ
• (3) die getrockneten Schichten (2) der wäßrigen Funktions-Beschichtungsstoffe mit Wasserbasislacken beschichtet, wonach man
• (4) die resultierenden Wasserbasislackschichten (3), ohne sie vollständig zu härten, mit Klarlacken beschichtet, wonach man
• (5) die Schichten (2), (3) und (4) gemeinsam härtet, wodurch die Funktionsschichten, die Basislackierungen und die Klarlackierungen resultieren;
  oder alternativ
• (3) die getrockneten Schicht (2) der wäßrigen Funktions-Beschichtungsstoffe mit Wasserbasislacken beschichtet,
• (3) die resultierenden Wasserbasislackschichten (3) und die getrockneten Schichten (2) gemeinsam härtet, wodurch die Funktionsschichten und die Basislackierungen resultieren, und
• (4) die Basislackierungen mit Klarlacken beschichtet, wonach man
• (5) die Klarfackschichten (4) härtet, wodurch die Klarlackierungen resultieren;

dadurch gekennzeichnet, daß man wäßrige Funktions-Beschichtungsstoffe, enthaltend

1. (A) mindestens ein vernetzbares Bindemittel,
2. (B) mindestens ein separates, wasserlösliches und/oder - dispergierbares Vernetzungssystem, das in und/oder auf der Matrix der nassen, trocknenden und/oder getrockneten Schichten (2) aus den wäßrigen Funktions-Beschichtungsstoffen für sich selbst partiell oder vollständig vernetzt, bevor die Bindemittel (A) vollständig vernetzen, und
3. (C) mindestens ein Pigment,

und wobei das Vernetzungssystem (B)

• (B1) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Ketogruppen im Molekül enthält, und
• (B2) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Hydrazidgruppen im Molekül enthält,
  und/oder
• (B3) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Ketogruppen und mindestens zwei Hydrazidgruppen im Molekül enthält,

umfaßt oder hieraus besteht,
verwendet.Accordingly, the new wet-on-wet process for producing multicoat color and / or effect paint systems comprising at least one functional layer and at least one color and / or effect solid-color topcoat or alternatively at least one color and / or effect basecoat and at least one clearcoat included in the process

• (1) aqueous functional coating materials applied to primed or unprimed substrate, after which one
• (2) drying the resulting layers of the aqueous functional coating materials without fully curing them,
• (3) the dried layers (2) of the aqueous functional coating materials coated with aqueous solid-color topcoats, after which
• (4) co-curing layers (2) and (3), resulting in the functional layers and the solid-color topcoats;
  or alternatively
• (3) coating the dried layers (2) of the aqueous functional coating materials with waterborne basecoats followed by
• (4) the resulting aqueous basecoat films (3) are coated with clearcoats without curing completely, followed by
• (5) co-curing layers (2), (3) and (4) to result in functional layers, basecoats and clearcoats;
  or alternatively
• (3) coating the dried layer (2) of the aqueous functional coating materials with waterborne basecoats,
• (3) the resulting waterborne basecoat layers (3) and the dried layers (2) co-cure, resulting in the functional layers and basecoats, and
• (4) the basecoats coated with clearcoats, after which
• (5) the clearcoat layers (4) cure, resulting in clearcoats;

characterized in that aqueous functional coating materials containing

1. (A) at least one crosslinkable binder,
2. (B) at least one separate, water-soluble and / or -dispersible crosslinking system which partially or completely crosslinks itself in and / or on the matrix of the wet, drying and / or dried layers (2) from the aqueous functional coating materials for itself completely crosslinking the binders (A), and
3. (C) at least one pigment,

and wherein the crosslinking system (B)

• (B1) at least one constituent containing on statistical average at least two keto groups in the molecule, and
• (B2) at least one constituent containing on statistical average at least two hydrazide groups in the molecule,
  and or
• (B3) at least one constituent which contains on statistical average at least two keto groups and at least two hydrazide groups in the molecule,

comprises or consists of
used.

The new wet-on-wet process for producing multicoat color and / or effect paint systems is referred to below as the "process according to the invention"

1. (A) mindestens ein vernetzbares Bindemittel,
2. (B) mindestens ein separates, wasserlösliches und/oder - dispergierbares Vernetzungssystem, das in und/oder auf der Matrix der nassen, trocknenden und/oder getrockneten Schichten (2) aus den wäßrigen Funktions-Beschichtungsstoffen für sich selbst partiell oder vollständig vernetzt, bevor die Bindemittel (A) vollständig vernetzen, und
3. (C) mindestens ein Pigment

und wobei das Vernetzungssystem (B)

• (B1) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Ketogruppen im Molekül enthält, und
• (B2) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Hydrazidgruppen im Molekül enthält,
  und/oder
• (B 3) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Ketogruppen und mindestens zwei Hydrazidgruppen im Molekül enthält,

umfaßt oder hieraus besteht.In addition, the novel aqueous functional coating materials were found containing

1. (A) at least one crosslinkable binder,
2. (B) at least one separate, water-soluble and / or -dispersible crosslinking system which partially or completely crosslinks itself in and / or on the matrix of the wet, drying and / or dried layers (2) from the aqueous functional coating materials for itself completely crosslinking the binders (A), and
3. (C) at least one pigment

and wherein the crosslinking system (B)

• (B1) at least one constituent containing on statistical average at least two keto groups in the molecule, and
• (B2) at least one constituent containing on statistical average at least two hydrazide groups in the molecule,
  and or
• (B 3) at least one constituent which contains on statistical average at least two keto groups and at least two hydrazide groups in the molecule,

comprises or consists of.

The new aqueous functional coating materials are referred to below as "functional coating materials according to the invention"

Other subjects of the invention will become apparent from the description.

In view of the prior art, it was surprising and unforeseeable for the person skilled in the art that the object on which the present invention was based could be achieved with the aid of the process according to the invention, in particular with the aid of the functional coating materials according to the invention. It was particularly surprising that the effect and / or hue shifts of waterborne basecoats which have frequently occurred in the substitution of conventional fuser fillers with aqueous polyurethane-based functional coating agents, by the addition of a separate, water-soluble and / or dispersible crosslinking system that is capable , in and / or on the matrix of wet, dry and / or dried layers of aqueous functional coating materials for themselves partially or completely crosslink before the binders (A) completely crosslink completely, could be significantly reduced. Above all, it was surprising that the process according to the invention and in particular the functional coating materials according to the invention provided functional layers which had a high resistance to stone chip even in layer thicknesses which were unusually low for fillers. The new functional layers showed excellent intercoat adhesion between the primers and the aqueous basecoat.

The efindungsgemäße process is used to produce color and / or effect multi-layer coatings on primed or unprimed substrates.

The new multicoat color and / or effect paint systems contain at least one functional layer and at least one color and / or effect solid-color topcoat or, alternatively, at least one color and / or effect basecoat and at least one clearcoat.

Functional layers i. S. of the present invention are surfacers i. S. of the German patent application DE 44 38 504 A1 or the European patent application EP 0 871 552 A1 , which have a high stone impact protection even in unusually thin layer thicknesses and also often make a contribution to the color and / or effect.
Suitable substrates are all those whose surface is not damaged by the application of heat and / or actinic radiation during the curing of the layers present thereon. Preferably, the substrates of metals, plastics, wood, ceramics, stone, textile, fiber composites, leather, glass, glass fibers, glass and rock wool, mineral and resin-bound building materials, such as gypsum and cement boards or roof tiles, and composites of these materials.

Accordingly, the inventive method and the functional coating materials according to the invention are not only outstandingly suitable for applications in the fields of automotive OEM finishing and automotive refinishing, but also for the coating of buildings in the interior and exterior and of doors, windows and furniture, for industrial coating , including coil coating, container coating and the impregnation and / or coating of electrical components, as well as for the painting of white goods, including household appliances, boilers and radiators, into consideration. In the context of industrial coatings, they are suitable for painting virtually all parts and articles for private or industrial use such as household appliances, small metal parts, such as nuts and bolts. Hub caps, rims, packaging, or electrical components, such as Motorwicktungen or transformer windings.

In the case of electrically conductive substrates primers can be used, which are prepared in a conventional manner from electrocoating. For this purpose, however, both anodic and cathodic electrodeposition paints, but especially cathodic electrodeposition paints, are considered. However, they can also have a cathodically deposited electrodeposition coating layer which is not thermally cured but only dried or partially cured. The electrodeposition coating or the electrodeposition coating layer can then be combined with the functional components according to the invention. Coating materials or to be used according to the invention to be used coating materials. These can then be cured together with the electrodeposition coating layer (wet-in-wet process).

Examples of suitable cathodic electrodeposition paints and, if necessary, wet-on-wet processes involving electrocoat films are described in US Pat Japanese Patent Application 1975-142501 (Japanese Laid-Open Publication JP 52-065534 A2 , Chemical Abstracts Unit No. 87: 137427) or the patents US 4,375,498 A1 . US 4,537,926 A1 . US 4,761,212 A1 . EP 0 529 335 A1 . DE 41 25 459 A1 . EP 0 595 186 A1 . EP 0 074 634 A1 . EP 0 505 445 A1 . DE 42 35 778 A1 . EP 0 646 420 A1 . EP 0 639 660 A1 . EP 0 817 648 A1 . DE 195 12 017 C1 . EP 0 192 113 A2 . DE 41 26 476 A1 or WO 98/07794 described.

In the case of non-functionalized and / or non-polar plastic surfaces, they may be subjected to a pre-treatment, such as with a plasma or with flames, or provided with a hydro-primer prior to coating in a known manner.

In the first step of the process according to the invention, at least one, in particular one, functional coating material according to the invention is applied to a substrate.

The functional coating material according to the invention comprises at least one, in particular one, binder (A). The binders (A) are not limited in their material composition. In addition, they may be oligomers or polymers.

Oligomers are understood as meaning resins which contain at least 2 to 15 monomer units in their molecule. By polymers are meant resins which contain at least 10 recurring monomer units in their molecule. In addition to these terms Römpp Lexikon Lacke und Druckfarben, Georg Thieme Verlag, Stuttgart, New York, 1998, "Oligomers", page 425 , referenced.

The binders (A) are preferably selected from the group consisting of physically, thermally, curently or thermally curable and with actinic radiation curable or crosslinkable, random, alternating and / or block-like, linear and / or branched and / or comb-like (Co) polymers of ethylenically unsaturated monomers, and polyaddition resins and polycondensation resins, selected These terms are supplementary Römpp Lexikon Lacke und Druckfarben, Georg Thieme Verlag, Stuttgart, New York, 1998, page 457, "Polyaddition" and "Polyaddition Resins (Polyadducts)" , such as Pages 463 and 464, "Polycondensates", "Polycondensation" and "Polycondensation Resins" directed.

Examples of suitable (co) polymers (A) are (meth) acrylate copolymers and partially saponified polyvinyl esters, in particular (meth) acrylic copolymers.

Examples of suitable polyaddition resins and / or polycondensation resins (A) are polyesters, alkyds, Polyurethanes, polylactones, polycarbonates, polyethers, epoxy resin-amine adducts, polyureas, polyamides or polyimides.

Of these, the polyurethanes (A) are advantageous, and therefore they are preferably used. The polyurethanes (A) are particularly preferably selected from the group consisting of saturated, unsaturated and grafted with olefinically unsaturated compounds, ionic or nonionic and ionic and nonionic stabilized polyurethanes

• der deutschen Patentanmeldung DE 199 14 896 A 1, Spalte 1,Zeilen 29 bis 49, Spalte 4, Zeile 23, bis Spalte 11, Zeile 5, und Spalte 19, Zeile 12, bis Spalte 20, Zeile 6,
• der deutschen Patentanmeldung DE 44 38 504 A 1, Seite 2, Zeile 58, bis Seite 4, Zeile 40, i. V. m. Seite 5, Zeile 24, bis Seite 7, Zeile 33,
• der deutschen Patentanmeldung DE 199 04 624 A1 , Seite 2, Zeile 35, bis Seite 5, Zeile 46, i. V. m. Seite 7, Zeile 36, bis Seite 8, Zeile 14,
• der deutschen Patentanmeldung DE 41 07 136 A1 , Seite 2, Zeile 23, bis Seite 4, Zeile 35, i. V. m. Seite 5, Zeilen 23 bis 59,
• der deutschen Patentanmeldung DE 199 04 317 A1 , Seite 9, Zeile 44, bis Seite 12, Zeile 11, i. V. m. Seite 16, Zeile 58, bis Seite 17, Zeile 2,

im Detail beschrieben. Ergänzend wird noch auf die eingangs zitierten deutschen Patentanmeldungen verwiesen.Polyurethanes (A) are known per se and are used for example in

• the German patent application DE 199 14 896 A 1, column 1, lines 29 to 49, column 4, line 23, to column 11, line 5, and column 19, line 12, to column 20, line 6,
• the German patent application DE 44 38 504 A 1, page 2, line 58, to page 4, line 40, i. V. m. Page 5, line 24, to page 7, line 33,
• the German patent application DE 199 04 624 A1 , Page 2, line 35, to page 5, line 46, i. V. m. Page 7, line 36, to page 8, line 14,
• the German patent application DE 41 07 136 A1 , Page 2, line 23, to page 4, line 35, i. V. m. Page 5, lines 23 to 59,
• the German patent application DE 199 04 317 A1 , Page 9, line 44, to page 12, line 11, i. V. m. Page 16, line 58, to page 17, line 2,

described in detail. In addition, reference is made to the German patent applications cited above.

The content of the functional coating materials according to the invention on binders (A) can vary widely and depends on the requirements of the individual case. The content is preferably from 10 to 80, preferably from 15 to 78, particularly preferably from 20 to 76, very particularly preferably from 25 to 74 and in particular from 30 to 72,% by weight, based in each case on the solids of the functional coating material.

• (B1) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Ketogruppen im Molekül enthält, und
• (B2) mindestens einen Bestandteil, der Im statistischen Mittel mindestens zwei Hydrazidgruppen im Molekül enthält,
  und/oder
• (B3) mindestens einen Bestandteil, der im statistischen Mittel mindestens zwei Ketogruppen und mindestens zwei Hydrazidgruppen im Molekül enthält,

umfaßt oder hieraus besteht.The functional Beschichtchtstoffe invention further comprise at least one, in particular a separate, water-soluble and / or -dispersible crosslinking system (B), wherein the crosslinking system (B), wherein the crosslinking system (B)

• (B1) at least one constituent containing on statistical average at least two keto groups in the molecule, and
• (B2) at least one constituent which contains on statistical average at least two hydrazide groups in the molecule,
  and or
• (B3) at least one constituent which contains on statistical average at least two keto groups and at least two hydrazide groups in the molecule,

comprises or consists of.

In the context of the present invention, the term "separate" makes it clear that the crosslinking system is independent or substantially independent of the crosslinking of the binder (A). It is essential here that the separate crosslinking system (B) in and / or on the matrix of wet, drying and / or dried layers of the functional coating materials according to the invention for themselves partially or completely crosslinked before the binder (A), in particular the Fully crosslinking polyurethanes (A) and thus completely crosslinking the layers as a whole.

The separate crosslinking system (B) to be used according to the invention can be of any desired composition, as long as it fulfills the requirement essential to the invention. In other words, the separate crosslinking system (B) to be used in the present invention can be selected based on the composition of the aqueous functional coating materials based on the above-described binders (A), especially the polyurethanes (A).

The separate crosslinking system (B) is a thermally curable crosslinking system. In addition to the keto groups, the separate crosslinking systems (B) may further comprise at least one of the complementary reactive functional groups for thermal crosslinking described below and / or at least one reactive functional group described below containing at least one bond activatable with actinic radiation. These reactive functional groups can then serve to crosslink the separate crosslinking systems (B) with the matrix of the layers of the functional coating materials according to the invention.

Electromagnetic radiation, preferably near infrared (NIR), visible light, UV radiation or X-radiation, in particular UV radiation, and / or corpuscular radiation, in particular electron radiation, are preferably used as the actinic radiation.

The separate crosslinking system (B) is externally crosslinking or self-crosslinking.

In the context of the present invention, the term "self-crosslinking" refers to the property of the crosslinking system (B) to be used according to the invention "by itself" crosslinking reactions. The prerequisite for this is that at least one constituent already contains both types of complementary reactive functional groups which are necessary for crosslinking, or reactive functional groups which can react with themselves. On the other hand, such externally crosslinking systems are those separate crosslinking systems (B) in which one type of the complementary reactive functional groups is present in a binder and the other type in a hardener or crosslinking agent. In addition to this is on Rompp Lexikon Lacke and printing inks, Georg Thieme publishing house, Stuttgart, New York, 1998, "hardening", pages 274 to 276, in particular page 275 , below, directed.

-C(O)-OH

-C(O)-N(CH₂-CH₂-OH)₂ -O-C(O)-CR⁵=CH₂ -OH -O-CR=CH₂ -NH₂ -C(O)-CH₂-C(O)-R -CH=CH₂ Examples of suitable complementary reactive functional groups to be used according to the invention are summarized in the following overview. In the overview, the variable R is an acyclic or cyclic aliphatic, an aromatic and / or an aromatic-aliphatic (araliphatic) radical; the variables R 'and R "stand for identical or different aliphatic radicals or are linked together to form an aliphatic or heteroaliphatic ring. Overview: Examples of complementary functional groups binder and crosslinking agent or crosslinking agent and binder SH -C (O) -OH -NH ₂ -C (O) -O-C (O) - -OH NCO -O- (CO) -NH- (CO) -NH ₂ -NH-C (O) -OR -O- (CO) -NH ₂ -CH ₂ -OH > NH -CH ₂ -OR -NH-CH ₂ -OR -NH-CH ₂ -OH -N (-CH ₂ -OR) ₂ -NH-C (O) -CH (-C (O) OR) ₂ -NH-C (O) -CH (-C (O) OR) (- C (O) -R) -NH-C (O) -NR'R " > Si (OR) ₂

-C (O) -OH

-C (O) -N (CH ₂ -CH ₂ -OH) ₂ -OC (O) -CR ⁵ = CH ₂ -OH -O-CR = CH ₂ -NH ₂ -C (O) -CH ₂ -C (O) -R -CH = CH ₂

The selection of the complementary reactive functional groups depends on the temperature range in which the complete curing of the matrix of the layers of the functional coating materials according to the invention, which also includes the binders (A), in particular the polyurethanes (A), takes place. The thermal curing of the separate crosslinking system (B) must take place at lower temperatures, since the functional coating materials according to the invention are thermally or thermally and actinic radiation-curable functional coating materials. The person skilled in the art can therefore, for a given group of functional coating materials according to the invention, easily select the appropriate complementary reactive functional groups on the basis of their general knowledge, if appropriate with the aid of simple orienting experiments.

• der deutschen Patentanmeldung DE 199 30 067 A1 , Seite 3, Zeilen 23 bis 56, i. V. m. Seite 4, Zeilen 23, bis Seite 7, Zeilen 19, Seite 7, Zeilen 20, Seite 9, Zeile 20, Seite 9, Zeilen 21 bis 29, Seite 9, Zeile 49, bis Seite 11, Zeile 37, Seite 11, Zeilen 38 bis 68, Seite 12, Zeile 30 bis 55, und Seite 16, Zeile 50, bis Seite 17, Zeile 13,
• der deutschen Patentanmeldung DE 199 14 896 A1 , Spalte 11, Zeile 6, bis Spalte 13, Zeile 55,
• der deutschen Patentanmeldung DE 199 04 317 A1 , Seite 3, Zeile 64, bis Seite 2, Zeile 2, i. V. m. Seite 4, Zeile 7, bis Seite 9, Zeile 43, und Seite 15, Zeilen 33 bis 49, i. V. m. Seite 16, Zeilen 30 bis 45, oder
• der deutschen Patentanmeldung DE 198 18 735 A1 ,Spalte zwei, Seiten 21 bis 46, Spalte 3, bis Spalte 6, Zeile 33, und Spalte 6, Zeile 55, bis Spalte 7, Zeile 35,

im Detail beschrieben.Examples of suitable constituents for the thermally or thermally and with actinic radiation curable separate crosslinking systems (B) to be used according to the invention which contain the complementary reactive functional groups described above are described, for example, in US Pat

• the German patent application DE 199 30 067 A1 , Page 3, lines 23 to 56, i. V. m. Page 4, lines 23, to page 7, lines 19, page 7, lines 20, page 9, line 20, page 9, lines 21 to 29, page 9, line 49, to page 11, line 37, page 11, lines 38 to 68, page 12, line 30 to 55, and page 16, line 50, to page 17, line 13,
• the German patent application DE 199 14 896 A1 , Column 11, line 6, to column 13, line 55,
• the German patent application DE 199 04 317 A1 , Page 3, line 64, to page 2, line 2, i. V. m. Page 4, line 7, to page 9, line 43, and page 15, lines 33 to 49, i. V. m. Page 16, lines 30 to 45, or
• the German patent application DE 198 18 735 A1 , Column two, pages 21 to 46, column 3, to column 6, line 33, and column 6, line 55, to column 7, line 35,

described in detail.

The curing with actinic radiation is carried out with the aid of reactive functional groups containing at least one, in particular one, activatable with actinic radiation bond.

In the context of the present invention, a bond which can be activated by actinic radiation is understood to mean a bond which becomes reactive upon irradiation with actinic radiation and undergoes polymerization reactions and / or crosslinking reactions with other activated bonds of its type which proceed by free-radical and / or ionic mechanisms. Examples of suitable bonds are carbon-hydrogen single bonds or carbon-carbon, carbon-oxygen, carbon-nitrogen, carbon-phosphorus or carbon-silicon single bonds or double bonds. Of these, the carbon-carbon double bonds are particularly advantageous and are therefore very particularly preferably used according to the invention. For the sake of brevity, they will be referred to as "double bonds" in the following

Accordingly, the preferred group according to the invention contains one double bond or two, three or four double bonds. If more than one double bond is used, the double bonds may be conjugated. According to the invention, however, it is advantageous if the double bonds are present in isolation, in particular each terminally, in the group in question here. According to the invention, it is particularly advantageous to use two, in particular one, double bond.

Examples of suitable groups are (meth) acrylate, ethacrylate, crotonate, cinnamate, vinyl ether, vinylester, dicyclopentadienyl, norbomenyl, isoprenyl, isopropenyl, alfyl or butenyl groups; Dicyclopentadienyl, norbornyl, isoprenyl, isopropenyl, allyl or butenyl ether groups or dicyclopentadienyl, norbornenyl, isoprenyl, isopropenyl, allyl or butenyl ester groups, but especially acrylate groups.

Examples of suitable components for actinic radiation curable separate crosslinker systems (B) are known from the German patent application DE 197 36 083 A1 , Page 7, line 3, to page 8, line 38, described in detail.

The selection of the actinic radiation curable separate crosslinking systems (B) depends primarily on the wavelength range in which activatable with actinic bonds bonds are activated. This wavelength range should be outside the range with which the functional coating materials according to the invention are cured. The person skilled in the art can therefore easily select suitable actinic radiation curable separate crosslinking systems (B) for a given actinic radiation curable functional coating material of the present invention, optionally with the aid of simple orienting experiments.

The externally crosslinking separate crosslinking system (B) contains at least one constituent (B 1) containing on statistical average at least two, preferably at least three, keto groups in the molecule. In addition, the separate crosslinking system (B) contains at least one constituent (B 2) which is included in the statistical Agent contains at least two hydrazide groups in the molecule. Preferably, the separate crosslinking system (B) consists of a component (B 1) and a component (B 2). The ratio of the two constituents (B 1) and (B 2) can vary very widely and depends on the functionality of the two complementary constituents.

Preferably, the component (B 1) is selected from the group consisting of oligomers and polymers containing terminal or lateral or terminal and lateral keto groups. Suitable oligomers and polymers are derived from the polymer classes described above for the binders (A), where (meth) Acrylate copolymers (B 1) are particularly advantageous and are therefore particularly preferably used.

Preferably, the components (B 2) are selected from the group consisting of low molecular weight compounds having at least two hydrazide groups and oligomers and polymers, the terminal or lateral or terminal and lateral hydrazide groups. Suitable oligomers and polymers are derived from the polymer classes described below. The low molecular weight compounds having two hydrazide groups in the molecule are preferably used.

Examples of suitable low molecular weight compounds having two hydrazide groups are the dihydrazides of organic dicarboxylic acids, such as phthalic acid, terephthalic acid, naphthalenedicarboxylic acid, 1,2-, 1,3- or 1,4-cyclohexanedicarboxylic acid, sebacic acid or adipic acid. Adipic dihydrazide is particularly preferably used

In a further embodiment, the self-crosslinking, separate crosslinking systems (B) contain at least one constituent (B 3) selected from the group consisting of oligomers and polymers which on statistical average have at least two, in particular at least three, terminal or lateral or terminal keto groups and at least two, in particular at least three, terminal or lateral or terminal and lateral hydrazide groups contained in the molecule, or they consist of this component (B 3).

The separate crosslinking systems (B) are commercially available substances and are used, for example, in the form of aqueous dispersions under the trademark Acronal®, in particular Acronal® A 603 or A 627, or under the trademark Luhydran®, in particular Luhydran® LR 8950 or 8975, from the BASF Aktiengesellschaft, under the brand name Viacryl®, in particular Viacryl® VSC 6270, 6286 or 6295, from the company Solutia or under the brand Setalux®, in particular Setalux® 6810 AQ-25 or XL 1141, by Akzo. In general, the adipic acid dihydrazide content of the aqueous dispersions is up to 10% by weight, based on the solids content of the aqueous dispersions.

The content of the functional coating materials according to the invention on the separate crosslinking systems (B) can vary very widely and depends on the requirements of the individual case. Preferably, the functional coating materials of the invention contain, based in each case on the solid, 1 to 50, preferably 2 to 48, particularly preferably 3 to 44, very particularly preferably 4 to 42 and in particular 5 to 40 wt .-% of (B).

The functional coating materials according to the invention contain at least one pigment (C).

Preferably, the pigments (C) are selected from the group consisting of color and / or effect, fluorescent, electrically conductive and magnetically shielding pigments, metal powders, organic and inorganic, transparent and opaque fillers and nanoparticles

The content of the functional coating materials according to the invention on the pigments (C) can vary widely. Preferably, the content is selected so that the quantitative ratio of pigments (C) to binders (A) and to the optionally present in the separate crosslinking systems (B) oligomers and polymers (pigment-binder ratio) at 0.1: 1 to 3 : 1, preferably 0.2: 1 to 2.8: 1, more preferably 0.3: 1 to 2.5: 1, most preferably 0.3: 1 to 2: 1 and especially 0.3: 1 to 1.5: 1 is.

Examples of suitable effect pigments are metal flake pigments such as commercial aluminum bronzes, according to DE 36 36183 A1 chromated aluminum bronzes, and commercial stainless steel bronzes and non-metallic effect pigments, such as pearlescent or interference pigments, platelet-shaped effect pigments based on iron oxide, which has a hue of pink to brown-red, or liquid-crystalline effect pigments. In addition, Römpp Lexikon Lacke und Druckfarben, Georg Thieme Verlag, 1998, pages 176, "Effect pigments" and pages 380 and 381 "Metal oxide mica pigments" to "Metallpigmente", and the patent applications and Patents DE 36 36 156 A1 . DE 37 18 446 A1 . DE 37 19 804 A1 . DE 39 30 601 A1 . EP 0 068 311 A1 . EP 0 264 843 A1 . EP 0 265 820 A1 . EP 0 283 852 A1 . EP 0 293 746 A1 . EP 0 417 567 A1 . US 4,828,826 A or US 5,244,649 A directed.

Examples of suitable inorganic color pigments are white pigments such as titanium dioxide, zinc white, zinc sulfide or lithopone; Black pigments such as carbon black, iron manganese black or spinel black; Colored pigments such as chromium oxide, chromium oxide hydrate green, cobalt green or ultramarine green, cobalt blue, ultramarine blue or manganese blue, ultramarine violet or cobalt and manganese violet, iron oxide red, cadmium sulfoselenide, molybdate red or ultramarine red; Iron oxide brown, mixed brown, spinel and corundum phases or chrome orange; or iron oxide yellow, nickel titanium yellow, chromium titanium yellow, cadmium sulfide, cadmium zinc sulfide, chrome yellow or bismuth vanadate

Examples of suitable organic color pigments are monoazo pigments, disazo pigments, anthraquinone pigments, benzimidazole pigments, quinacridone pigments, quinophthalone pigments, diketopyrrolopyrrole pigments, dioxazine pigments, indanthrone pigments, isoindoline pigments, isoindolinone pigments, azomethine pigments, thioindigo pigments, metal complex pigments, perinone pigments, perylene pigments, phthalocyanine pigments or aniline black.

In addition, Römpp Lexikon Lacke und Druckfarben, Georg Thieme Verlag, 1998, pages 180 and 181, "Iron Blue Pigments" to "Iron Oxide Black", pages 451 to 453, "Pigments" to "Pigment Volume Concentration," page 563, "Thioindigo Pigments," Page 567 "Titanium Dioxide Pigments," pp. 400 and 467, "Naturally Occurring Pigments," page 459, "Polycyclic Pigments," page 52, "Azomethine Pigments," "Azo Pigments," and page 379, "Metal Complex Pigments."

Examples of fluorescent pigments (daylight pigments) are bis (azomethine) pigments.

Examples of suitable electrically conductive pigments are titanium dioxide / tin oxide pigments.

Examples of magnetically shielding pigments are pigments based on iron oxides or chromium dioxide.

Examples of suitable metal powders are powders of metals and metal alloys aluminum, zinc, copper, bronze or brass.

Examples of suitable organic and inorganic fillers are chalk, calcium sulfates, barium sulfate, silicates such as talc, mica or kaolin, silicas, oxides such as aluminum hydroxide or magnesium hydroxide or organic fillers such as plastic powder, in particular of polyamide or polyacrylonitrile. In addition, reference is made to Rompp Lexikon Lacke und Druckfarben, Georg Thieme Verlag, 1998, pages 250 ff., »Fillers«.

Preferably, mica and talc are used when the scratch resistance of the coatings prepared from the powder coatings of the invention is to be improved.

In addition, it is advantageous to use mixtures of platelet-shaped inorganic fillers such as talc or mica and non-platelet inorganic fillers such as chalk, dolomite calcium sulfates, or barium sulfate, because this makes it possible to adjust the viscosity and flow behavior very well.

Examples of suitable transparent fillers are those based on silicon dioxide, aluminum oxide or zirconium oxide.

Suitable nanoparticles are selected from the group consisting of hydrophilic and hydrophobic, in particular hydrophilic, nanoparticin based on silica, alumina, zinc oxide, zirconium oxide and the polyacids and heteropolyacids of transition metals, preferably of molybdenum and tungsten, having a primary particle size <50 nm, preferably 5 to 50 nm, in particular 10 to 30 nm. Preferably, the hydrophilic nanoparticles have no matting effect. Particular preference is given to using nanoparticles based on silicon dioxide.

Very particular preference is given to using hydrophilic pyrogenic silicon dioxides whose agglomerates and aggregates have a chain-like structure and which can be prepared by the flame hydrolysis of silicon tetrachloride in an oxyhydrogen flame. These are marketed, for example, by Degussa under the Aerosil® brand. Very particular preference is also given to precipitated water glasses, such as nanohektorites, which are sold, for example, by Südchemie under the Optigel® brand or by Laporte under the Laponite® brand

In addition, the functional coating materials according to the invention may also contain at least one additive (D), as is commonly used in the field of functional coating materials.

Examples of suitable additives are molecularly soluble dyes, light stabilizers, such as UV absorbers and reversible radical scavengers (HALS); antioxidants; low and high boiling ("long") organic solvents; Venting means; Wetting agents; emulsifiers; slip additives; polymerization inhibitors; Catalysts for crosslinking; thermolabile radical initiators; thermally and actinic radiation curable reactive thinner; Adhesion promoters; Leveling agents; film-forming aids; Rheology aids (thickeners); Flame retardants; Corrosion inhibitors; waxes; driers; Biocides and / or matting agents; as described, for example, in the textbook »Lackadditive« by Johan Bieleman, Wiley-VCH, Weinheim, New York, 1998, or in the German patent application DE 199 14 896 A1 , Column 14, page 26, to column 15, line 46, will be described in detail.

Methodically, the preparation of the functional coating materials according to the invention has no special features, but takes place by mixing the constituents described above in customary and known mixing units, such as stirred tank, Ultraturrax, inline dissolver, extruder or kneader.

Methodically, the application of the functional coating materials of the invention also has no special features, but can by all conventional application methods, such as. Spraying, knife coating, brushing, pouring, dipping, trickling or rolling. Preferably, spray application methods are used, such as compressed air spraying, airless spraying, high rotation, electrostatic spray application (ESTA), optionally combined with hot spray application such as hot air hot spraying. Of course, these application methods can also be used for the application of solid-color topcoats, aqueous basecoats and clearcoats.

After application, the layers of the functional coating materials according to the invention are dried without curing them completely. Preferably, temperatures of from 20 to 80, preferably from 20 to 70 and in particular from 20 to 65 ° C. are used. The drying can be assisted by laminar air flows. Preferably, drying times of 30 seconds to two hours, preferably one minute to one hour, and more preferably one minute to 45 minutes are used

According to the invention, during this process step, the separate, water-soluble and / or dispersible crosslinking system (B) partially or completely crosslinks on and / or in the matrix of the wet, dry and / or dried layers before the binders (A) crosslink completely. If the separate crosslinking systems (B) are curable also or exclusively with actinic radiation, the layers are irradiated with actinic radiation

Radiation sources, such as high pressure or low pressure mercury vapor lamps optionally doped with lead to open a beam window up to 405 nm, or electron beam sources are contemplated for irradiation with actinic radiation. Further examples of suitable methods and apparatus for curing with actinic radiation are disclosed in US Pat German patent application DE 198 18 735 A1 , Column 10, lines 31 to 61 described.

In the further course of the process according to the invention, the dried layer of the functional coating material according to the invention is coated with at least one, in particular one, aqueous solid-color topcoat, resulting in a solid-color topcoat layer. The application methods described above can be used. Examples of suitable aqueous solid-color topcoats are described in the patent applications cited above, in particular in the German patent application DE 199 14 896 A1 , Column 1, lines 29 to 49 described. Thereafter, the solid-color topcoat layer and the dried layer and, optionally, the dried electrodeposition coating layer are cured together thermally or thermally and with actinic radiation. The curing methods described above are used. The thermal curing can be carried out in customary and known circulating air ovens or with the aid of IR lamps. This results in a multi-layer coating according to the invention which comprises at least one, in particular one, functional layer and at least one, in particular one, color and / or effect solid-color topcoating.

Alternatively, in the further course of the process according to the invention, the dried layer is coated with at least one, in particular a water-based lacquer, resulting in a water-based lacquer layer. Examples of suitable water-based paints are in the patent applications cited above, in particular in the German patent application DE 199 14 896 A1 , Column 1, lines 29 to 49 described. The waterborne basecoat is then dried without fully curing. The drying methods described above can be used.

In the further course of the process according to the invention, at least one, in particular one, clearcoat is applied to the dried aqueous basecoat, thereby resulting in a clearcoat. Examples of suitable clearcoat materials are described in the patent applications cited above, in particular in the German patent application DE 199 14 896 A1 , Column 17, line 57, to column 18, line 30 described. Unless they are powder coatings, the application methods described above can be used. Examples of suitable application methods for powder coatings are described, for example, in the product information of the company Lacke + Farben AG, "Powder coatings", 1990.

Subsequently, the dried layer of the functional coating material according to the invention, the aqueous basecoat layer and the clearcoat layer and optionally the electrodeposition coating layer are cured thermally or thermally and with actinic radiation, wherein the methods and apparatuses described above can be used. This results in a multicoat color and / or effect paint system according to the invention which comprises at least one functional layer, at least one color and / or effect aqueous basecoat and at least one clearcoat

In a further variant of the method according to the invention, the dried layer of the functional coating material according to the invention and the waterborne basecoat layer are cured together. Then at least one clearcoat is applied to the resulting waterborne finish, after which the resulting clearcoat (s) are cured, using the methods described above and devices can be applied. This also results in an inventive color and / or effect multi-layer coating of the structure described above

The multicoat color and / or effect paint systems according to the invention produced by the process according to the invention have an excellent flow, a uniformly smooth surface, a high intercoat adhesion and excellent optical properties (appearance). Compared with multicoat color and / or effect paint systems which do not have a functional layer i. S. of the present invention, but only have a Einbrennfüllerlackierung occur when using one and the same water-based paint little or no effect and / or hue shifts.

Examples and comparative experiment Production Example 1 The preparation of an aqueous dispersion containing a polyurethane (A)

For the examples and the Vergleichsersuch was the aqueous dispersion of a polyurethane (A) according to the in the German patent application DE 44 38 504 A1 , Page 5, lines 24 to 42, »1. Preparation of water-dilutable polyurethane resins; 1.1 polyurethane resin «, specified rule produced

Examples 1 and 2 and comparative experiment V1 The preparation of the functional coating materials 1 and 2 according to the invention (Examples 1 and 2) and of the noninventive functional coating material V1 (Comparative Experiment V1)

The functional coating materials 1 and 2 according to the invention and the functional coating material V1 not according to the invention were prepared by mixing the constituents specified in Table 1 in the order given and homogenizing. Table 1: The composition of the functional coating materials 1 and 2 according to the invention (Examples 1 and 2) and of the noninventive functional coating material V1 (Comparative Experiment V1) ingredients Examples: 1
V1 2 Pigment paste: Polyurethane dispersion of preparation example 1 32, 1 32, 1 32.1 Additol® XW 395 (commercial leveling agent from Solutia) 0.48 0.48 0.48 Surfactant S (commercial wetting agent from BASF Aktiengesellschaft) 0.5 0.5 0.5 Aerosil® R 972 (commercial fumed silica from Degussa) 0.34 0.34 0.34 Aerosil® R 805 (commercial fumed silica from Degussa) 1.02 1.02 1.02 Deionized water 1.45 1.45 1.45 - Flammruß 101 (commercial soot from Degussa) 0.9 0.9 0.9 Sicomix black 00-6190 (commercial black pigment from Degussa) 2.4 2.4 2.4 Talc 10 MO Micro (commercial filler from Luzenac de France) 3.6 3.6 3.6 Titan Rutile R 900-28 (commercial titanium dioxide pigment from DuPont) 0.76 0.76 0.76 Aluminum silicate ASP 200 (commercial filler from Engelhard) 5.8 5.8 5.8 Deionized water 1.4 1.4 1.4 Deionized water 1.3 1.3 1.3 letdown: Viacryl® VSC 6295 (commercial aqueous dispersion of a methacrylate copolymer crosslinkable with adipic dihydrazide, manufacturer: Solutia) 9,9 19.8 Polyurethane dispersion of preparation example 1 16.5 - 32.1 Cymel® 1133 (commercially available melamine resin from Dyno-Cytec) 0.9 0.9 0.9 Pluriol® P900 (commercial polyether polyol from BASF Aktiengesellschaft) 0.8 0.8 0.8 Byk ® 346 (commercial silicone surfactant from Byk Chemie) 0.4 0.4 0.4 Byketol® WS (commercial additive from Byk Chemie) 0.8 0.8 0.8 Serad ® FX 1010 (commercial rheology aid from Servo Delden) 10 10 10 Deionized water 9.1 15.25 2.95 Solids content: 35.84 35.86 35.81 Pigment to binder ratio: 0.64 0.5 0.89

Examples 3 and 4 and Comparative Experiments V2 and V3 The Production of Multicoat Paint Systems According to the Invention (Examples 3 and 4) and a Multicoat Painting Not According to the Invention (Comparative Examination V2)

For example 3, the functional coating material of example 1 and for example 4 the functional coating material of example 2 were used.

For the comparative experiment V2, the functional coating material of Comparative Experiment V1 was used.

For the production of multi-layer roofing, steel panels were coated with a customary and known cathodic electrodeposition coating. On the electrodeposition coating, a commercially available filler (Ecoprime® 130 from BASF Coatings AG) was pneumabsch applied and then baked for 30 minutes at 130 ° C, so that a surfacer coating resulted.

The coated surface of the steel panels was in each case half coated with the functional coating materials of Examples 1 and 2 (Examples 3 and 4) and Comparative Experiment V1 (Comparative Experiments V2), so that always half of the conventional surfacer coating remained visible. The resulting layers of the functional coating materials of Examples 1 and 2 and Comparative Experiment V1 were dried at 60 ° C for 10 minutes

Subsequently, the entire coated surfaces of the steel panels were coated with a commercially available water-based paint in the shade of brilliant silver from BASF Coatings AG and dried for 10 minutes at 60 ° C. Thereafter, the two layers were baked for 30 minutes at 130 ° C in a convection oven.

The resulting multicoat paint systems according to the invention of Examples 3 and 4 and the resulting multicoat paint system of Comparative Experiment V2 not according to the invention were compared colorimetrically directly with the standard "baked-in Ecoprime® 130 / waterborne coating". In the case of the multicoat system of Example 3 according to the invention, a hue shift D of only 2.9 and in the case of the inventive multicoat paint system of Example 4 a hue shift D of only 1.5, whereas the multicoat paint system of Comparative Experiment V2 not according to the invention a hue shift D of 6.3 showed.

Claims (10)

1. Wet-on-wet process for producing multicoat colour and/or effect coating systems which comprise at least one functional coat and at least one solid-colour and/or effect topcoat or alternatively at least one colour and/or effect basecoat and at least one clearcoat, in which process

   (1) aqueous functional coating materials are applied to primed or unprimed substrates, and then

   (2) the resulting films of the aqueous functional coating materials, without being fully cured, are dried,

   (3) the dried films (2) of the aqueous functional coating materials are coated with aqueous solid-colour topcoat materials, and then

   (4) the films (2) and (3) are cured together, to give the functional coats and the solid-colour topcoats;

   or alternatively

   (3) the dried films (2) of the aqueous functional coating materials are coated with aqueous basecoat materials, and then

   (4) the resulting aqueous basecoat films (3), without being fully cured, are coated with clearcoat materials, and then

   (5) the films (2), (3), and (4) are cured together, to give the functional coats, the basecoats, and the clearcoats;

   or alternatively

   (3) the dried films (2) of the aqueous functional coating materials are coated with aqueous basecoat materials,

   (4) the resulting aqueous basecoat films (3) and the dried films (2) are cured together, to give the functional coats and the basecoats, and

   (5) the aqueous basecoats are coated with clearcoat materials, and then

   (6) the resulting clearcoat films (4) are cured, to give the clearcoats;

   characterized in that aqueous functional coating materials are used comprising

   (A) at least one crosslinkable binder,

   (B) at least one separate, water-soluble and/or -dispersible crosslinking system which independently effects partial or complete crosslinking in and/or on the matrix of the wet, drying and/or dried films (2) of the aqueous functional coating materials before the binders (A) crosslink completely, and

   (C) at least one pigment.

   and the crosslinking system (B) comprising or consisting of

   (B1) at least one constituent containing on average per molecule at least two keto groups, and

   (B2) at least one constituent containing on average per molecule at least two hydrazide groups; and/or

   (B3) at least one constituent containing on average per molecule at least two keto groups and at least two hydrazide groups.
2. Process according to Claim 1, characterized in that the binders (A) are selected from the group consisting of ionically or nonionically, and also ionically and nonionically, stabilized polyurethanes which are saturated, unsaturated and/or grafted with olefinically unsaturated compounds.
3. Process according to either of Claims 1 and 2, characterized in that the pigments (C) are selected from the group consisting of colour and/or effect pigments, fluorescent pigments, electrically conductive pigments, and magnetically shielding pigments, metal powders, organic and inorganic, transparent and opaque fillers, and nanoparticles.
4. Process according to either of Claims 1 to 3, characterized in that the primer on the substrates is prepared by applying electrocoat materials, overcoating the resulting electrocoat films, without fully curing them, with the aqueous functional coating materials and the solid-colour topcoat materials or alternatively with the aqueous functional coating materials, the aqueous basecoat materials, and the clearcoat materials, then curing all films together or curing the electrocoat films, the films of the functional coating materials, and the aqueous basecoat films together and the clearcoat films separately.
5. Aqueous functional coating materials comprising

   (A) at least one binder,

   (B) at least one separate, water-soluble and/or -dispersible crosslinking system which independently effects partial or complete crosslinking in and/or on the matrix of the wet, drying and/or dried films (2) of the aqueous functional coating materials before the binders (A) crosslink completely, and

   (C) at least one pigment,

   and the crosslinking system (B) comprising or consisting of

   (B1) at least one constituent containing on average per molecule at least two keto groups, and

   (B2) at least one constituent containing on average per molecule at least two hydrazide groups; and/or

   (B3) at least one constituent containing on average per molecule at least two keto groups and at least two hydrazide groups.
6. Aqueous functional coating materials according to Claim 5, characterized in that the binders (A) are selected from the group consisting of ionically or nonionically, and also ionically and nonionically, stabilized polyurethanes which are saturated, unsaturated and/or grafted with olefinically unsaturated compounds.
7. Aqueous functional coating materials according to Claim 5 or 6, characterized in that the pigments (C) are selected from the group consisting of colour and/or effect pigments, fluorescent pigments, electrically conductive pigments, and magnetically shielding pigments, metal powders, organic and inorganic, transparent and opaque fillers, and nanoparticles.
8. Aqueous functional coating materials according to any of Claims 5 to 7, characterized in that the pigment:binder ratio is from 0.1:1 to 3:1.
9. Use of the aqueous functional coating materials according to any of Claims 5 to 8 to produce multicoat colour and/or effect coating systems.
10. Use according to Claim 9, characterized in that the aqueous functional coating materials are used to produce functional coats, primer-surfacer coats, antistonechip primer coats, solid-colour topcoats, or basecoats.