Method for producing a printed decorative panel

Abstract

The disclosure relates to a method for producing a printed panel, comprising the following steps: a) providing a flat carrier; b) optionally applying a resin layer to the flat carrier; c) optionally applying a paper layer or nonwoven layer to the flat carrier; d) optionally calendering the produced layer structure, in particular at a temperature between 40 C. and 250 C., and e) optionally applying a printing substrate to the flat carrier; characterized in that the method has the following further steps: f) printing an application amount of radiation-curing printing ink onto the carrier, and g) curing the previously applied printing ink by treating the printing ink with radiation, wherein h) at least one parameter of radiation used in step g) is adapted to an application amount of radiation-curing printing ink, wherein step h) is based on an application amount of the radiation-curing printing ink determined by a sensor during the printing process, wherein at least one parameter of radiation used in step g) is adapted during the printing on the carrier according to step f).

Claims

1. A method for producing a printed panel, comprising the steps: a) providing a plate-shaped carrier; b) optionally applying a resin layer onto the plate-shaped carrier; c) optionally applying a paper or nonwoven layer onto the plate-shaped carrier; d) optionally calendering the resulting layer structure, in particular at a temperature between 40 and 250 C.; e) applying a printing substrate onto the plate-shaped carrier; wherein the method comprises the further steps: f) printing the carrier with a radiation-curable printing ink; g) curing the previously applied printing ink by treating the printing ink with radiation, h) obtaining a signal from at least one sensor during printing step f), wherein the signal is indicative of the amount of radiation-curable ink being printed on the carrier; and i) varying at least one parameter of the radiation used in step g) based on the signal.

2. The method according to claim 1, wherein a warning is issued in case of a deviation of the determined application amount from the desired application amount.

3. The method according to claim 1, wherein step h) is based on a predetermined application amount of the radiation-curable ink.

4. The method according to claim 1, wherein at least one parameter of radiation used in step g) is adapted independently in a plurality of locally different areas.

5. The method according to claim 1, wherein step f) is realized by use of a digital printing method.

6. The method according to claim 1, wherein varying the at least one parameter of radiation includes varying a number of emitters, a power of at least one emitter, or an irradiation duration of the radiation-curable printing ink.

7. The method according to claim 1, wherein obtaining the signal includes the at least one sensor determining the amount of radiation-curable ink being printed on the carrier by detecting a discharge area of a print head.

8. The method according to claim 1, wherein obtaining the signal includes the at least one sensor determining the amount of radiation-curable ink being printed on the carrier by determining the amount of ink which flows to a print head.

Description

(1) The disclosure is explained below with reference to the figures and an exemplary embodiment.

(2) FIG. 1 shows a device in an embodiment of the disclosure in a first operating mode;

(3) FIG. 2 shows the device of FIG. 1 in a second operating mode; and

(4) FIG. 3 shows the device of FIG. 1 in a second operating mode.

(5) Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

(6) Example embodiments will now be described more fully with reference to the accompanying drawings.

(7) FIG. 1 shows a device for producing a printed panel in an embodiment of the present disclosure for carrying out a method according to the present disclosure.

(8) The device comprises a supply means 10 for supplying a plate-shaped carrier 12, so that the carrier 12 is transported in the direction of the arrow 14 the a travel direction. Downstream of the supply means 10 an application unit 16 for applying a resin layer 18 onto the supplied carrier 12 is disposed. In the travel direction downstream of the application unit 16 a supply means 20 for applying a paper or nonwoven layer 22 onto the plate-shaped carrier 12 is arranged. Not shown is an adjoining unit for calendering, in particular under heat, of a layer structure comprising the carrier, the resin layer 18 and the paper or nonwoven layer 22.

(9) In order to prepare a printing of the carrier 12 according to FIG. 1, moreover, an application unit 24 for applying a printing substrate 26 onto the carrier 12 is provided. In the travel direction of the carrier 12 downstream of the application unit 24, a printing of the carrier 12 may follow. For this purpose, a printing unit 28 for printing the carrier 12 with an application amount of radiation-curable printing ink 30 is provided. In order to cure the radiation-curable printing ink 30, a radiation unit 32 for treating the printed carrier with radiation for curing the radiation-curable printing ink 30 is provided, so that the carrier 12 is provided with cured printing ink 44. With reference to the radiation unit 32 it is shown in FIG. 1 that the radiation unit 32 has five emitters 34, 36, 38, 40, 42. These can be arranged side by side, but basically any arrangement of the emitters 34, 36, 38, 40, 42 can be encompassed by the present disclosure.

(10) In FIG. 1 it is further shown that the device comprises a control unit 46, which, for example, is connected to the printing unit 28 and the radiation unit 32 for data transmission by means of a data connection 48. As a result, the control unit 46 can be fed with data relating to an application amount of the radiation-curable printing ink 30 and can determine at least one parameter of the radiation emitted by the radiation unit 32 based on the application amount. The data relating to the application amount can correspond to the data transmitted to the printing unit 28 or can be generated by sensors (not shown) for determining the applied printing ink 30.

(11) The number of sensors used and not shown in detail of the printing unit 28 and their respective configuration is in principle not limited. For example, determination of the application amount of the radiation-curable printing ink during the printing process can be carried out by use of at least one optical sensor that detects a discharge area of a print head. Alternatively or additionally, it may be provided that the determination of the application amount of the radiation-curable printing ink is carried out during the printing process by use of at least one optical sensor that detects the printed carrier. Alternatively or additionally it may be further provided that the determination of the application amount of the radiation-curable printing ink is carried out during the printing process by use of a flow sensor, which detects an ink line upstream of a print head or within a print head.

(12) This allows the control unit 46 to transmit the at least one parameter to the radiation unit 32. The radiation unit 32 in turn can cure the printing ink 30 by use of this parameter. This is likewise shown in FIGS. 2 and 3, and the above description can similarly be applied to the FIGS. 2 and 3.

(13) FIG. 1 shows that a comparatively large application amount of radiation-curable printing ink 30 is applied onto the carrier 12. In order to cure the printing ink 30, therefore, all five emitters 34, 36, 38, 40, 42 are used.

(14) In FIG. 2 it is indicated that a comparatively small application amount of radiation-curable printing ink 30 is applied onto the carrier 12. In order to cure the printing ink 30 therefore only three emitters 34, 38, 42 are used.

(15) FIG. 3 shows a further example. According to FIG. 3, a part of the printing ink 30 is applied onto the carrier 12 with a comparatively small application amount of radiation-curable printing ink 30 and additionally also a part of the printing ink 30 is applied onto the carrier 12 with a comparatively high application amount of radiation-curable ink 30. In this case, a curing or irradiation of the printing ink 30 can take place locally differently by use of the emitters 34, 36, 38 and 42. It can be seen that a versatile adaptation can be achieved even with differently printed decoration areas.

(16) Regardless of the specific embodiment of the device or the method, by use of five emitters 34, 36, 38, 40, 42, for example, the following parameter selection can be done, wherein the application amounts are related to the entire decoration. With an application amount of <2 g/m.sup.2, for example, one emitter can be used, with an application amount of 2 g/m.sup.2 to <5 g/m.sup.2, for example, two emitters can be used. With an application amount of 5 g/m.sup.2 to <8 g/m.sup.2, for example, three emitters can be used, with an application amount of 8 g/m.sup.2 to <10 g/m.sup.2, for example, four emitters can be used, and with an application amount of 10 g/m.sup.2, for example, five emitters can be used, wherein the above values being purely exemplary.

(17) Specifically, it is in principle possible, for example, that for a given UV-curable ink with applied amounts of ink of <1 ml/m.sup.2 one UV emitter is used, wherein the ink is exposed to a dose of 280 mJ/cm.sup.2. Furthermore, it can be provided that with applied amounts of ink of 1 ml/m.sup.2 to 5 ml/m.sup.2 two consecutively arranged UV emitters are used, wherein the ink is exposed to a dose of 550 mJ/cm.sup.2, and that with applied amounts of ink of >5 ml/m.sup.2 three consecutively arranged UV emitters are used, wherein the ink is exposed to a dose of 830 mJ/cm.sup.2. The feed rate of the panel is 25 m/min in all examples. Here, when using three consecutively arranged UV emitters, for example, a dwell time in the direct focus of the emitter, which may have an area corresponding to the moving direction of the carrier of about 10 mm, can be, for example, about 0.024 s, wherein the dwell time in an extended focus, which may have an area corresponding to the moving direction of the carrier of about 50 mm, can be about 0.12 s. Further, the dose was measured in the wavelength range 230-410 nm using a mercury emitter.

(18) In a manner which is obvious to a person skilled in the art, the abovementioned parameters may differ in addition to the specific ink used, for example, based on a doping of the emitter.

(19) The dose can be determined, for example, by a product marketed under the name UV-Micro-Puck by UV-Technik Meyer GmbH.

(20) The abovementioned adaptations are further dependent on the desired curing result, which is realized by the effect of the emitter on the ink. Thus, the radiation used to act on the ink may be selected in particular against the background that the ink is optionally compressed together with a layer disposed on the ink, such as a melamine resin layer or lacquer layer, for introducing haptically perceptible structures. For this purpose, optionally a stronger hardening or a stronger dose acting on the ink may be necessary than with an ink layer which is not subjected to compression.

(21) The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.