The invention relates to a thermally deformable sheet or film and a process for producing such a plate or film. Furthermore, the invention relates to a thermally deformed plate as well as various applications of such plates.

State of the art

Thermally deformable plates are used in numerous applications, such as in the automotive industry for body parts of cars, trucks, caravans, construction equipment, commercial vehicles, in bathrooms for bathtubs or shower trays, in the furniture industry as furniture films, in the construction sector, E & E housings for leisure and sports equipment, or in the train and airplane industries. While such plates are excellent in processability, they often do not achieve the required in the respective field of application properties. In particular, the mechanical and physical-chemical properties such as scratch resistance, chemical resistance, for example, for automotive applications are often not sufficient.

In the prior art, various solutions have already described how to increase the surface properties of such thermally deformable plates. In EP 1737654 Bl for example in which a two-stage curable lacquer is applied to a sheet material by rolling, doctoring or flooding and subsequently physically dried by removing the solvent of the varnish is expelled described "dual your" system. The plate with a in such a partially hardened lacquer layer a thermoforming or a thermoplastic deformation is subsequently subjected After molding, the lacquer layer is crosslinked to completion by means of UV radiation and fully cured in this state of the art two problems arise:.. First, the partially cured sheet is not stackable and not shelf stable.

Another approach of the prior art follows the strategy of the subsequent painting of the plate or foil. In this case, a plastic plate or film is thermoformed and subsequently painted, for example by spray coating or flow coating. Although this method provides to good results, it is very complicated and involves a lot of overspray and rework. In addition, coating streaks can occur with this method; in spray painting an unwanted Orangepeel and for flooding a rainbow effect is often observed. Even with these methods, there are problems with the

Paint application in those places that are difficult to access due to the geometry of the thermoformed panel.

A third approach of the prior art is the so-called two-component injection molding ( "2K-injection molding"). In this, a liquid multi-component reactive system is introduced into the cavity of the mold of the injection molding and during the subsequent embossing step, the coating uniformly on the surface of the molded part in an injection molding machine distributed. the coating is cured in the molding tool so that the component can be removed from the mold. After removal of the component, the curing of the lacquer by means of UV radiation. This method provides very scratch-resistant surfaces, but it is extremely expensive, used only for small-scale components and also unsuitable for shade locations. an application for automobile bodies is very difficult to implement in a reasonable cost.

Summary of the Invention

Thus, all processes of the prior art are either costly, complicated or do not provide the entire surface with uniform coatings of the paint layer.

The object of the present invention is therefore to provide a thermoformable sheet or film in which these disadvantages do not occur.

This object is achieved by a thermally deformable sheet or film comprising a thermoplastic plastic plate or plastic film and having thereon a coating film having at least two components, characterized in that the coating film comprises as a first constituent a thermoformable component and having as a second component a thermally curable component ,

Such sheet or film may be provided directly by the manufacturer of the thermoplastic plastic plate or plastic film, by plate or plastic film, a resist is applied to the thermoplastic plastic, which has two stages curable. The first stage of curing is carried out, for example, even the manufacturer of the thermoplastic plastic plate or plastic film, while the second stage - the final curing of the paint - is at the location of the thermal molding process and indeed made simultaneously with the thermoforming process.

The coating film is not to be understood as meaning that it is two separate layers, each one of the two components. Rather, the coating film is to be understood that the two constituents of the coating film are mixed together and blended.

When applied to the plastic film or sheet of the coating is still liquid. Thereafter, the curing of the first component takes place. The cured first component is thermoformable, that is, by the action of temperature and pressure, the first component can be deformed reversibly. After curing of the first component, the coating film is already so hard that a storage and stacking of the plates or films and the subsequent thermoforming of such a plate or sheet without adversely affecting the optical characteristics and surface quality, in particular the gloss, is possible. However, the coating film is not yet off or cured completely. Preferably, the coating film after curing of the first component and before the thermal curing of the second component to a chemical resistance to acetone of less than 5 minutes. After curing of the second component, the coating film in a chemical resistance to acetone of about 5 minutes.

It is therefore contemplated that the first thermoformable component is cured, so that thermoforming is possible. Originally, on application of the coating film of the first component or the components of the first component were still fluid not cured and.

Preferably, the second component of the coating film hardens completely during the thermoforming of the plate or foil. Optionally, a small, preferably thermal, post curing may not be required. As a curing process that is meant in which, by polymerization of the monomers and oligomers in the coating film, the polymerization process used so that there is an increase in the hardness of the coating film.

Thermally deformable sheet or film will be understood that the sheet or film, is deformed by pressure and temperature. This deformation of the second component of the coating film cures. The thermally deformable sheet or film can also be thermoplastically deformable.

In another aspect, the invention relates to a process for preparing a thermoformable sheet or slab.

The method for producing a thermally deformable plastic plate or plastic film comprising the steps of

(I) providing a thermoplastic plastic plate or plastic film,

(Ii) applying a coating material with a first curable component that is thermoplastic deformable in the cured state and a second, thermally curable constituent,

(Iii) curing only the first curable component.

In one aspect, the invention also relates to a method for producing a deformed plastic plate or plastic film comprising either the steps of

(I) providing a thermoplastic plastic plate or plastic film,

(Ii) applying a coating material with a first curable component that is thermoplastic deformable in the cured state and a second, thermally curable constituent,

(Iii) curing the first curable component only, ie without cure of the second component,

(Iv) thermo-forming the plastic sheet into a desired three-dimensional shape with simultaneous curing of the thermally curable component;

or comprising the steps of

(A) providing a thermoformable sheet or film of the aforementioned type and

(B) thermoforming of the plastic sheet into a desired three-dimensional shape with simultaneous curing of the thermally curable component.

Application areas such sheets or films include, for example, the automotive, rail and aerospace industries; the furniture industry; the construction industry; the plumbing; Freetime and sports.

In the automotive industry, in the web and in the Flugzeugindunstrie example of the exterior area come as body panels of cars, trucks, caravans, construction machinery, trucks such as roof modules, decorative trim, bumpers, trunk covers, full-area bodywork parts or the interior area such as panels, decorative panels, trims, displays functional operating units etc. into consideration. In the furniture industry furniture foils, furniture parts and the like are exemplified can. In plumbing z. to mention as bathtubs or shower trays. Generally, such films can be used as housing in all areas of industry, suitcase or equipment housing, etc., or in the construction industry, E & E packages, leisure and sports equipment.

Detailed description of the invention:

Below advantages and details of the invention are explained in detail.

The terms foil or plastic film and plate or plastic plate can be used as part of the patent application interchangeably and films and plates equally meant even if only film or sheet is mentioned.

Plastic film or sheet:

The thermoplastic resin sheet or film provides the support for the coating film is, and is thermally deformable. The thermoplastic resin sheet may be a single- or multilayer film formed. In the case of a multilayer thermoplastic plastic plate or film it is preferably a coextrudate. Preferably, the plastic sheet or film, a planar multi-layer composite body which comprises at least a substrate layer and a further layer.

As a main component for the thermoplastic resin sheet or film thermoplastic materials such as thermoplastic polymers. As the thermoplastic material in the invention, a plastic is meant that can be shaped thermoplastically in a certain temperature range. The thermoplastic deformability is a reversible process, so that the thermoplastic material by cooling and reheating can be repeated until in the deformable state as often as desired. Among thermoplastic materials pure plastics (homopolymers, copolymers or hetero-) and plastic blends are combined (mixtures of various plastics).

As thermoplastic materials, polyolefins, styrene polymers, polycarbonate, etc. may be mentioned (PC), polyacrylates, polyesters. In the group of polyolefins such as polyethylene or polypropylene can be mentioned. In the group of styrenic polymers such as acrylonitrile-butadiene-styrene can terpolymers (ABS), polystyrene (PS), impact modified polystyrene (HI-PS), acrylonitrile-styrene Acrylester (ASA), other co-polymers are known comprising styrene units. The polyesters may be mentioned polyethylene terephthalate (PET) or modified copolymers such as glycol modified polyethylene terephthalate (PETG). Among the most important representatives of the polyacrylates polymethylmethacrylate counts (PMMA) and impact-modified polymethyl methacrylate (HI-PMMA). Furthermore, the thermoplastic materials may for example Thermoplastic Elastomers (TPE),

Furthermore, a blend of plastics can be present as a thermoplastic material or it may be necessary to add additional materials to achieve desired properties. As a blend of the aforementioned plastics such as ABS / PMMA or ABS / PC can be mentioned.

If the thermoplastic resin sheet or film formed multi-layered, the individual layers can also contain the aforesaid polymers. Combinations of PMMA and ABS, or PC and PMMA, such as plastic films with ABS or PC as the major component for the carrier layer and PMMA as a further layer of the plastic film are worth mentioning. On the upper layer of plastic film (eg, PMMA) is then applied the paint layer.

Optionally, the layers of regrind, recycled or regenerated material may contain (for example from previous production steps or the setting of the extrusion line or edge trimming). Also, colorant and / or UV additives can be added.

It can also be added a matting agent, by which is generally understood as additives which influence the surface of a coating so that their degree of gloss decreases. Usually associated with this is an increase in surface roughness, which shows an improved processing behavior in the subsequent process, the lamination. Suitable matting agents are known in the art and include, for example, inorganic fillers, in particular silica or crosslinked polymers in bead form ( "polymer beads"), preferably Acrylatperlen. The added amount is preferably between 0.1 wt.% And 5 wt.%.

Among colorants, pigments, dyes or effect pigments are referred to. Unlike dyes pigments are insoluble in the carrier medium. As a carrier medium is used to refer to the material into which the pigment is incorporated, for example, a lacquer or a plastic. Dyes and pigments include jointly the colorants and can be inorganic or organic, colored or non-colored.

The ultraviolet component of sunlight can cause photodegradation. In order to prevent effects of this type or delay, UV additives can be added. Depending on the mode of action of these UV additives are divided in UV absorbers and UV stabilizers. UV absorbers lead to absorption of the UV radiation which passes through the polymer and convert it into heat energy. UV stabilizers inhibit the free radicals which are formed by the irradiation with UV radiation, and stop further degradation.

The thickness of the substrate layer is preferably between 50 μιη and 5 mm. Any additional layers preferably have a thickness between 5 μιη and 1 mm.

Varnish layer:

The paint for the coating film is originally a multi-component lacquer (at least a two-component paint) or a varnish of at least two components includes that cure differently. Concretely, multicomponent lacquers a mixture of monomers and oligomers in a variety of polymerization (= curing).

In this case, two components are provided, which can harden independently. The first component is already hardened in the finished product (the thermally deformable sheet or film). For example, the first component may also be a thermally curable component. In this case, the second component at a higher temperature must be curable, as the first ingredient.

Preferably, the first component is a curable by means of UV-light component in the paint, that is, in the finished product, a cured by means of UV-light component.

Possible curable by means of UV light components, for example, acrylate oligomers such as urethane (meth) acrylate oligomers such as lambs ® UA 9072 from BASF. Other ingredients are reactive diluents, photoinitiators, where appropriate, defoamers and UV additives.

It is preferably provided that the UV light-curable acrylate oligomers component, preferably comprising urethane (meth) acrylate oligomers, reactive diluents and photoinitiators. Photo initiators are chemical compounds that are subject after irradiation with UV light of a photolysis and so form reactive species such as radicals and can cause a polymerization. Reactive diluents are substances which decrease the viscosity of the paint and become part of the paint in the subsequent hardening of the varnish by copolymerization. For example, epoxides, styrene or acrylates are also suitable.

As a UV light in the context of the invention radiation having a wavelength in the range of about 380 nm is understood to 10 nm.

Unlike conventional two-component coating systems, the formulation has no pot life.

The thermally curable component preferably comprises blocked (or blocked) isocyanates and polyols. A blocked isocyanate is an addition compound of a highly reactive isocyanate, for example, with alcohols ( "Urethane"), or with amines ( "ureas"). At higher temperatures, these isocyanates are then released again, and then enter into the polymerization reaction with the polyols as a reaction partner. Suitable polyols include aromatic polyester polyols can be mentioned, such as Terol 250 ® polyol from Huntsman.

The coating film is produced by applying the lacquer to the substrate and partially curing. The partially curing affects only the first component and not the second component. By weight by using UV additives (UV absorbers and UV stabilizers) in the amount of 0.01 to 5.% To the materials and colorants used in the underlying layers are protected from UV radiation, whereby the color stability and the uniform material properties is significantly improved over the period of use when irradiated with UV light. Furthermore, can be the cover layer or the transparent UV lacquer or performed with different colorants. In the coating film, nanoparticles to improve various properties can be included.

There are many known methods for applying coatings. Thus, brushing, rolling, spraying, flow coating, pouring, knife coating, drums, rollers and scrapers may be mentioned. By these methods are applied coating systems which generally contain organic solvents or water, or both. The solvents are usually air-dried after the coating process in drying chambers, and thus a large energy and space is required.

Preferably, the coating is substantially free of solvents as solvents are environmentally questionable. Also have solvent borne coatings from other disadvantages, for example, result from the fact that may arise fluctuations in thickness in the resist layer by the evaporation of the lacquer.

The coating film may be formed either glossy or matte.

Since many plastics such as PMMA / ABS or PC / PMMA coextrudates at between 140 ° C and 210 ° C are thermoformable, the blocked isocyanate is preferably such that, preferably between 140 ° C and 210 ° C 160 ° C to 190 , particularly preferably releases ° C between 165 ° C to 185 ° C ° C, the isocyanate. When blocked isocyanates, for example aromatic isocyanates (eg monomeric diphenyl methane diisocyanates) and / or aliphatic isocyanates may be added (for example, isophorone diisocyanate). By means of suitable additives, such as blocking agent, the temperature can be set, wherein the second component cures.

The varnish must be thermoformable before thermal curing of the second component. After thermal curing (that is, after curing, also the second component) of the paint can be thermoplastic deformable still, but it can also be formed by thermosetting.

There is furthermore the possibility of applying a protective film on the partially crosslinked lacquer coating to protect the surface of the transport process and further processing. Protectors of this type are usually made of polyethylene or PET, they can have a back-sided adhesive layer.

The thickness of the top layer is preferably between 1 and 100 μιη μιη, preferably about 5 to μιη 20th

The mixing ratio between the first component and the second component is preferably between 3: 1 and 1: 3 by mass proportions.

Thermally curable component, all ingredients are combined, which are required for the thermal curing, while all of the ingredients are combined under UV light curable component, the curing by UV light.

Embodiments and further advantages of the invention:

Fig. 1 shows schematically the construction of a thermally deformable plate according to the example.

FIGS. 2a, 2b show FT-IR spectra of the influence of temperature on cure

Show top layer, Fig. 2b shows a detailed view in the region 750-1050 cm "1 shows.

An advantage of the invention that either the step of subsequent painting or UV curing is not necessary. Also, the stacking strength of the plate having the partially cured coating layer is advantageous over the prior art. A further advantage lies in the more uniform curing of the three-dimensionally formed component.

The thermally deformable plate can be deformed with a protective film, which is not possible with conventional dual-cure systems because only physically crosslinked. Characterized the surface during processing and in further

Processing steps or additional protection during transport. Thermoforming is possible on conventional systems. The coating film surface after curing of the first component (and before curing of the second component) finger dry, stackable and storable. The lacquer layer is elastic and stretchable.

The following table shows the properties achieved depending on the thermoforming parameters are listed by way of example. It is a composite body with the following structure:

Composite body having a layer structure (see Fig. 1):

1 Lackdeckschicht 10 μιη

2 PMMA 30 microns

3 PMMA 60 microns

4 PC/ABS-Blend 150 μιη

μιη 5 PC / ABS blend with regrind 1010

6 PC/ABS-Blend 40 μιη

The layers 2 to 6 and were co-extruded onto the layer 2, a varnish as a varnish layer (layer 1) was coated by means of roller. The composition of the paint comprises a mixture of the results summarized in Table 1 Components:

Table 1: composition of the coating of the coating film:

The ingredients 1 to 3 of the paint shown in Table 1 form the first component having an acrylic component. The ingredients 1 to 3 were cured by means of UV light, and the resulting component is thermoplastically deformable after curing.

The mixture of components 4 to 7 forming the second part of the coating film. These components are cured in a second step. In the following

Table 2 properties of the coating film after curing of the first component ( "before deformation") was investigated and after curing of the second component by means of thermal treatment by thermoforming. The thermoforming temperature is 180 ° C.

Table 2: Analysis of the resist layer after the curing of the first component and before or after curing of the second component.

a Test implemented:

Fingernail test by BMW Group Standard GS 97034-2

Fingernail Tester Plastic PMMA =

Diameter = 16 mm; Thickness 1 mm

Rounding radius from the edge of the pane = 0.5 mm

Harte = Shore D85

Test speed = 200 (+/- 20) mm / s; Test load = 20 N

Evaluation of the results according fingernail test:

Rating 1: no trace visible (no change in the surface area)

Note 2: Weak / slight trace visible

Note 3: Significant trace visible.

Assessment of the results in accordance with acetone test:

The test panels are rated by comparing it with the reference surface for each liquid according to the following described classification code, classification code in accordance with DI N EN 12720: 2009-07:

5 = No visible changes (no damage)

4 = Slight gloss or color change (reflection) or a detectable marker delimited 3 = Slight marking from multiple angles to see z. B. almost complete circle or circular area 2 = Strong mark (edges), but the surface structure is largely unchanged

1 = Severe marking, the surface structure is changed or the surface material is completely or partly destroyed or the paper adheres to the surface

Evaluation of sunscreen tests according GMW 14445:

1 = No change

2 = Slight gloss or color change, light swelling or other tolerable

Effects / changes

3 = Significant gloss or color change, strong swelling, blister, peeling or other intolerable effects / changes

4 = Very significant gloss or color change, very strong swell, blister, peeling or other non-tolerable effects / changes

Fig. 1 shows schematically the thermally deformable plate of the embodiment in cross-section, comprising a top layer 1 and a thermoplastic resin sheet comprising a total of five layers 2, 3, 4, 5, 6. The substrate layer 5 takes up a major share. The other layers 2, 3, 4, 6 may contribute additional mechanical and / or optical properties. On the surface of the coating film 1 in the example shown, a protective film 10 is indicated. of course, the plastic film or sheet does not contain 5 layers, may for example also have only one or two or more layers.

Fig. 2 shows FT-IR spectra of the coating film 1 according to the invention. The solid line shows the coating film to paint application and curing of the first component (of the acrylic components 1 to 3 in the example shown) to the plastic plate. Thereafter, this plate was pre-dried at 70 ° C for 24 hours to remove the residual moisture of the plastic plate. The FT-IR spectrum of the coating film is stippled. The difference with the measurement before storage at 70 ° C / 24 hrs is low.

After thermoforming of the plate (dash-dotted line), the FT-IR spectrum changes significantly, in particular, the transmission at the characteristic band at 900 cm is 1 significantly higher. The physico-chemical properties of the surface of the coating film after curing of the second component thereby improved significantly. It was surprising that a thermal curing as the final curing step of a coating film for plastics provided the same surface quality (physical and chemical) as a UV-curing as a final step. In the thermal curing of coatings on plastics such results could be obtained conventionally never.

CLAIMS

1. Thermally deformable sheet or film comprising a thermoplastic plastic plate or plastic film (2, 3) and disposed thereon coating film (1) having at least two components, characterized in that the lacquer layer (1) comprises as a first constituent a thermoformable component, and as a second component comprising a thermally curable component.

2. Thermally deformable sheet or film according to claim 1, characterized in that the thermally curable component is selected such that it cures at a temperature at which the thermoplastic plastic plate or plastic film (2, 3) is thermoformable.

3. Thermally deformable sheet or film according to claim 1 or claim 2, characterized in that the cured, thermoformable component is a cured by means of UV light or by means of temperature, preferably by means of UV-light component.

4. Thermally deformable sheet or film according to claim 3, characterized in that the cured by means of UV-light component is a polymer comprising acrylate oligomers, reactive diluents and photoinitiators.

5. Thermally deformable sheet or film according to any one of claims 1 to 4, characterized in that the thermally curable component comprising blocked isocyanates and polyols.

6. Thermally deformable plate according to one of claims 1 to 5, characterized in that arranged on the cover layer (3) a protective film (4).

7. Deformed plate or foil comprising a plate according to one of claims 1 to 6, wherein the thermally curable component is cured.

8. The component comprising a thermoplastically deformed plate according to claim. 7

9. The component according to claim 8, characterized in that the component is a body part, a sanitary component, a furniture film or a housing.

10. A process for the preparation of a thermally deformable plastic plate or plastic film according to any one of claims 1 to 6, comprising the steps of

(I) providing a thermoplastic plastic plate or plastic film (2, 3),

(Ii) applying a coating material with a first curable component that is thermoplastic deformable in the cured state and a second, thermally curable constituent,

(Iii) curing only the first curable component.

11. The method according to claim 10, characterized in that the first curable component is cured thermally or by UV-light.

12. A method for producing a deformed plastic plate or plastic film according to claim 7, comprising the steps of either

(I) providing a thermoplastic plastic plate or plastic film (2, 3),

(Ii) applying a coating material with a first curable component that is thermoplastic deformable in the cured state and a second, thermally curable constituent,

(Iii) curing only the first curable component.

(Iv) thermo-forming the plastic sheet into a desired three-dimensional shape with simultaneous curing of the thermally curable component;

or comprising the steps of

(A) providing a thermoformable sheet or film according to any one of claims 1 to 6 and

(B) thermoforming of the plastic sheet into a desired three-dimensional shape with simultaneous curing of the thermally curable component.