THERMALLY DEFORMABLE PLATE

Abstract

A thermally deformable plate or film, comprising a thermoplastic plastic plate or plastic film (2, 3) and, arranged thereupon, a lacquer cover layer (1) having at least two constituents, characterized in that the lacquer cover layer (1) has a thermoformable component as a first constituent and a thermally curable component as a second constituent.

Claims

1. A thermally deformable plate or film, comprising a thermoplastic plastic plate or plastic film and, arranged thereupon, a lacquer cover layer having at least two constituents, wherein the lacquer cover layer has a thermally deformable component as a first constituent and a thermally curable component as a second constituent, wherein the cured, thermoformable component is a component that is cured by means of UV light.

2. A thermally deformable plate or film according to claim 1, wherein the thermally curable component is selected such that it is cured at a temperature, at which the thermoplastic plastic plate or plastic film is thermoformable.

3. (canceled)

4. A thermally deformable plate or film according to claim 1, wherein the component that is cured by means of UV light is a polymer, including acrylate oligomers, reactive diluents, and photo initiators.

5. A thermally deformable plate or film according to claim 1, wherein the thermally curable component comprises blocked isocyanates and polyols.

6. A thermally deformable plate or film according to claim 1, wherein there is arranged a protective layer on top of the cover layer.

7. A deformed plate or film, comprising a plate according to claim 1, wherein the thermally curable component has been cured.

8. An element, comprising a thermoplastically deformed plate according to claim 7.

9. An element according to claim 8, wherein the element is a car body element, a sanitary element, a furniture film or a housing.

10. A method for the production of a thermally deformable plastic plate or plastic film according to claim 1, comprising the following steps: (i) providing a thermoplastic plastic sheet or plastic film, (ii) applying a lacquer having a first constituent curable via UV light, which is thermoplastically deformable in the cured condition, and a second, thermally curable constituent, (iii) curing of only the first curable component.

11. (canceled)

12. A method for the production of a deformed plastic plate or plastic film according to claim 7, comprising either the following steps: (i) providing a thermoplastic plastic sheet or plastic film (2. 3); (ii) applying a lacquer having a first constituent curable via UV light, which is thermoplastically deformable in the cured condition, and a second, thermally curable constituent; (iii) curing of only the first curable component; (iv) thermoforming the plastic plate into a desired three-dimensional shape while simultaneously curing the thermally curable component; or comprising the following steps: (a) providing a thermoplastically deformable plate or film according to claim 1, and (b) thermoforming the plastic plate into a desired three-dimensional shape while simultaneously curing the thermally curable component.

Description

EXAMPLES AND FURTHER ADVANTAGES OF THE INVENTION

[0052] FIG. 1 schematically shows the configuration of a thermally deformable plate according to the example.

[0053] FIG. 2a, 2b show FT-IR spectres, which show the influence of temperature on the curing of the cover layer, wherein FIG. 2b shows a detailed view in the range of 750 to 1050 cm.sup.−1.

[0054] An advantage of the invention is that either the work step of subsequent lacquer application or of UV curing is omitted. Also the stackability of the plate having the partially cured lacquer layer is advantageous in comparison to prior art. Another advantage lies in the more uniform curing of the three-dimensional element.

[0055] The thermally deformable plate may be deformed having a protective film, which is not possible with common dual-cure systems, as these are simply cross-linked in a physical way. In this way, the surface is additionally protected in the processing process as well as in further processing steps or in the transport, respectively. Thermoforming is possible on conventional facilities. The surface of the lacquer cover layer is finger-dry, stackable and storage-stable upon curing of the first constituent (and before curing of the second constituent). The lacquer layer is elastic and stretchable.

[0056] In the following table, the obtained characteristics are listed as a function of the thermoforming parameters by way of an example, this being a composite having the following configuration:

[0057] Composite having a layered configuration (see FIG. 1):

TABLE-US-00001 1 lacquer cover layer  10 μm 2 PMMA  30 μm 3 PMMA  60 μm 4 PC/ABS blend  150 μm 5 PC/ABS blend with regenerate 1010 μm 6 PC/ABS blend  40 μm

[0058] The layers 2 to 6 were co-extruded, and onto layer 2 there was applied a lacquer as a lacquer cover layer (layer 1) by means of a roller. The composition of the lacquer comprises a mixture of the components summarized in table 1:

TABLE-US-00002 TABLE 1 Composition of the lacquer of the lacquer cover layer: Component % w/w Description 1 urethane (meth)acrylate- 35 Laromer ® UA 9072 oligomer 2 1,6-hexane dioldiacrylate 10 Reactive diluent 3 2,4,6-trimethylbenzoyl-  3 Ciba ® Darocur ®TPO diphenyl-phosphine oxide photoinitiator 4 isocyanate 25 Isophoron-diisocyanate 5 polyol 24 Terol 250  ® 6 3,5-dimethyl pyrazol  2 blocking agent 7 Dibutyl-tin-dilaurate (DBTL)  1 Meister ZI 4401 catalyst

[0059] The constituents 1 to 3 of the lacquer according to table 1 represent the first constituent having an acrylic component. The constituent 1 to 3 were cured by means of UV light, and the resulting component is thermoplastically deformable upon curing.

[0060] The mixture of the components 4 to 7 represents the second constituent of the lacquer cover layer. These components are cured in a second step. In the following table 2 below, the characteristics of the lacquer cover layer after curing the first component (“before deformation”) and after curing the second components by means of thermal treatment by thermoforming were examined. The thermoforming temperature is about 180° C.

TABLE-US-00003 TABLE 2 Examination of the lacquer layer after curing the first constituent and before or after, respectively, curing the second constituent. Acetone test Finger nail test Treatment acc. to DIN EN (acc. to BMW Sun cream test temperature 12720: 2009 Group Standard according to [C. °] dwell time 5 min) GS 97034-2).sup.a GMW14445 Before deformation 1 3 4 160 1 3 4 170 2 1 1 180 5 1 1 190 5 1 1 200 5 1 1 .sup.aTest carried out: Finger nail test according to BMW Group Standard GS 97034-2 Finger nail tester plastic material = PMMA Diameter = 16 mm; thickness 1 mm Rounded radius starting from disc edge = 0.5 mm Hardness = Shore D85 Test speed = 200 (+/−20) mm/s; test force = 20 N

[0061] Evaluation of the results according to finger nail test: [0062] grade 1: no trace visible (no change of the surface) [0063] grade 2: mild/small trace visible [0064] grade 3: clear trace visible.

[0065] Evaluation of the results according to acetone test:

[0066] The test panels were evaluated by comparison with the reference surface for each liquid according to the qualification code described in the following, qualification code according to DIN EN 12720:2009-07: [0067] 5=No visible changes (no damage) [0068] 4=Slight change of gloss or colour (reflection) or detectable limited marking [0069] 3=Mild marking to be observed at various angles, e.g., nearly complete circle or circular area [0070] 2=Strong marking (edges), with the surface structure, however, being more or less unchanged [0071] 1=Strong marking, the surface structure is changed, and the surface material is completely or partially destroyed, or the paper adheres to the surface

[0072] Evaluation of the sun cream test according to GMW 14445: [0073] 1=No change [0074] 2=Slight change of gloss or colour, little swelling or any other acceptable effects/changes [0075] 3=Significant change of gloss or colour, heavy swelling, blister, peel-off or any other not-acceptable effects/changes [0076] 4=Very significant change of gloss or colour, very heavy swelling, blister, peel-off or any other not-acceptable effects/changes

[0077] FIG. 1 schematically shows the thermally deformable plate of the example in a cross-sectional view, comprising a cover layer 1 and a thermoplastic plastic plate comprising in total five layers 2, 3, 4, 5, 6. The substrate layer 5 therein is the major part. The remaining layers 2, 3, 4, 6 may provide additional mechanical and/or optical characteristics. On the surface of the lacquer cover layer 1 in the example shown, there is indicated a protective layer 10. The plastic film or plate need not contain 5 layers, it may, however, also contain only one or two or several layers.

[0078] FIG. 2 shows FT-IR spectres of the lacquer cover layer 1 according to the invention. The continuous line shows the lacquer cover layer after the application of lacquer and curing of the first constituent (the acrylic components 1 to 3 in the example shown) onto the plastic plate. Then this plate was pre-dried at 70° C. for 24 hours in order to remove any residual moisture of the plastic plate. The FT-IR spectrum of the lacquer cover layer is indicated using dots. The difference to the measurement before storage at 70° C./24 hours is little.

[0079] Upon thermoforming of the plate (dot dashed line), the FT-IR spectre will change significantly; in particular the transmission at the characteristic band at about 900 cm becomes markedly increased. The physico-chemical features of the surface of the lacquer cover layer upon curing of the second constituent were improved significantly. Surprisingly, a thermal curing as a final curing step of a lacquer cover layer for plastic material provided the same surface quality (in physical and chemical regard) as UV curing as a final step. In the thermal curing of lacquers onto plastic materials it has never been possible to obtain such results.