Cookware having a decorative layer and method for producing a decorative layer
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-13
- Publication Date
- 2026-03-18
AI Technical Summary
Existing cookware with decorative coatings lacks durability and cooking performance, particularly when exposed to high temperatures, and often mimics stainless steel appearance without its advantageous properties.
A cookware with a decorative layer made of die-cast aluminum or carbon steel, coated using physical vapor deposition with metals like titanium, chromium, zirconium, or tungsten, which provides a shiny or matte finish similar to stainless steel, while maintaining heat conduction and resistance properties.
The solution achieves a durable, heat-resistant, and aesthetically appealing decorative layer that reflects at least 50% of incident light, mimicking stainless steel appearance without the cooking disadvantages, through a method that ensures high adhesion, hardness, and scratch resistance.
Smart Images
Figure EP2024063129_21112024_PF_FP_ABST
Abstract
Description
[0001] Description
[0002] Cookware with a decorative layer and method for producing a decorative layer
[0003] Technical area
[0004] The invention relates to a cookware item with a decorative coating for heating food, comprising a base, in particular for placing on a heat source, and a wall connected to the base and extending upwards from the base. Such cookware items include, for example, a pot, a pan, a roasting pan, or a casserole dish.
[0005] State of the art
[0006] From EP 0 966 910 B1, it is known to provide cookware with a coating of ceramic nitride material, in particular zirconium nitride, whereby the non-stick effect is achieved on the inside of the cookware and a decorative layer is provided on the outside of the cookware. Unlike with a coating with titanium nitride, discoloration due to direct exposure to flames is avoided. The coating is applied to a base metal that has been polished to a high gloss, such as stainless steel, carbon steel, titanium, or the like.
[0007] The use of chromium to provide a multilayer PVD coating with a decorative appearance similar to stainless steel is known from US 2014 / 0242413 Al. This involves a layer of Zr-Cr-X, where X can be carbon, nitrogen, or oxygen.
[0008] The object of the invention is to provide a cookware with a decorative coating.
[0009] Description of the invention
[0010] In a cookware item according to the invention with a decorative coating, comprising a base, in particular for placing on a heat source, and a wall connected to the base and extending upwards from the base, wherein at least part of an outer side of the base and / or an outer side of the wall has a decorative layer, at least part of an outer side of the base and / or an outer side of the wall is made of die-cast aluminum or carbon steel. The decorative layer comprises one or more metals selected from titanium or chromium or zirconium or tungsten in metallic form and the decorative layer is applied by physical vapor deposition.
[0011] A decorative layer of titanium, chromium, or zirconium in metallic form has a metallic luster, also referred to as silvery or brightly lustrous, whereas tungsten has a black luster. It is irrelevant for the understanding of the invention whether a mirror-like luster or a matte luster is produced.
[0012] Carbon steel, also called carbon steel, is steel that, in addition to its main component, iron, contains carbon as a secondary component. Since "C" is the chemical symbol for carbon, carbon steel is also called C-steel. The carbon content can be up to 2.1%.
[0013] Aluminum alloys are alloys that consist predominantly of aluminum, as aluminum can be alloyed with numerous metals. There are wrought aluminum alloys, which are intended for further processing by rolling, forging, and extrusion, and cast materials, which are used in foundries. Therefore, aluminum alloys are generally divided into wrought and cast alloys.
[0014] Zirconium, titanium, chromium, aluminum and tungsten are each present in the metallic compositions customary for the PVD process, in which admixtures of other metals may also be present.
[0015] The layer is applied using the PVD process using a scattering body made of the metal from which the layer is to be made. The scattering body can also contain multiple metals. In conventional PVD processes, the layer is created using these metals as scattering bodies (targets).
[0016] Advantageously, the decorative layer can consist of titanium in metallic form, of titanium in combination with nitrogen, and of titanium in combination with nitrogen and carbon. This forms a layer of Ti, TiN, or TiCN. Such a layer has a copper-colored or rose-gold luster. The decorative layer can be applied by physical vapor deposition using a titanium scattering body and a reactive gas containing nitrogen and a reactive gas containing carbon, such as C2H2.
[0017] Advantageously, the decorative layer can consist of titanium in metallic form or of titanium and aluminum combined with nitrogen. This forms a layer of Ti, TiAlN. Such a layer has a copper-colored or rose-gold luster. The decorative layer can be applied by physical vapor deposition using a scattering body made of titanium and aluminum and a reactive gas containing nitrogen.
[0018] Advantageously, the decorative layer can consist of chromium in metallic form or of chromium combined with nitrogen. This forms a layer of Cr, CrN. Such a layer has a bright luster. The decorative layer can be applied by physical vapor deposition using a chromium scattering body and a reactive gas containing nitrogen.
[0019] Advantageously, the decorative layer may consist of titanium and chromium, titanium and zirconium, chromium and zirconium, or titanium, chromium, and zirconium in metallic form. Such a layer exhibits a bright luster. The decorative layer may be applied by physical vapor deposition using a scattering element, either of titanium and chromium, or of titanium and zirconium, or of chromium and zirconium, or of titanium and chromium and zirconium.
[0020] Advantageously, the decorative layer can consist of titanium in metallic form or of titanium combined with carbon. This forms a layer of Ti, TiC. Such a layer has a black luster. The decorative layer can be applied by physical vapor deposition using a titanium scattering body and a reactive gas containing carbon, such as C2H2.
[0021] Advantageously, the decorative layer can consist of chromium in metallic form or of chromium combined with carbon. In particular, a layer of Cr, Cr3C2 is formed. Such a layer has a black luster. The decorative layer can be applied by physical vapor deposition using a chromium scattering body and a reactive gas containing carbon, such as C2H2.
[0022] Advantageously, the decorative layer can consist of tungsten in metallic form or of tungsten combined with carbon. This forms a layer of W, WC. Such a layer has a black luster. The decorative layer can be applied by physical vapor deposition using a tungsten scattering body and a reactive gas containing carbon, such as C2H2.
[0023] Advantageously, the decorative layer can consist of titanium and chromium, titanium and tungsten, chromium and tungsten, or titanium, chromium, and tungsten, each combined with carbon. Such a layer exhibits a black luster. The decorative layer can be applied by physical vapor deposition using a scattering element made of either titanium and chromium, titanium and tungsten, chromium and tungsten, or titanium and chromium and tungsten, and using a reactive gas containing carbon, such as C2H2.
[0024] Advantageously, this decorative layer can have a layer thickness of 0.05 - 1.5 x 10-6 m.
[0025] Advantageously, the decorative layer can be applied directly to the outside of the floor and / or the wall.
[0026] Advantageously, the outer side of the base and / or wall can be provided with a carrier layer made of one or more metals selected from titanium, chromium, zirconium, or tungsten, with the decorative layer applied to the carrier layer. The carrier layer can be applied by physical vapor deposition using the respective metal as a scattering element.
[0027] This carrier layer can have a layer thickness of 0.1 - 0.3 x 10-6 m.
[0028] Advantageously, the surface roughness of the outer surface of the floor and / or the wall before coating may be at most 20 * 10-6 m, whereby a lower surface roughness, approximately from 0.5 * 10- 6 m to 3 * 10- 6 m, improves the uniformity of the decorative layer.
[0029] Advantageously, the decorative layer may have a surface finish such that at least 50% of the incident visible light is reflected by direct reflection, preferably at least 70%. This can be influenced, for example, by polishing the outer surface prior to applying the decorative layer or the carrier layer.
[0030] Advantageously, the decorative layer can have a SCI color value of 10° D65 according to Cielab, with L* from 55 to 80, a* from -2 to 3, and b* from -3 to 7. This creates a stainless steel appearance without the cookware exhibiting the disadvantageous cooking properties of stainless steel. Cielab color measurement using the SCI method includes the gloss components, using illuminant D65 and an angle of incidence of 10°.
[0031] It can be particularly advantageous if the decorative layer has an SCI colour value 10 ° D65 according to Cielab with L* from 60 to 65, a* from - 1 to 1 and b* from 4 to 5.
[0032] The invention further relates to a method for producing a cookware item with a decorative layer which is produced by physical vapor deposition, the cookware item having a base, in particular for placing on a heat source, and a wall which is connected to the base and extends upwards from the base. The outer side of the base and / or the wall is at least partially coated with a decorative layer made of metal by physical vapor deposition, one or more metals selected from titanium or chromium or zirconium or tungsten in metallic form being used to produce the decorative layer made of metal.
[0033] Advantageously, before applying the decorative layer, the outer side of the base and / or the wall can be provided with a carrier layer selected from zirconium, titanium, chromium, and tungsten in metallic form, or a combination of two or more of these metals. The carrier layer is applied by physical vapor deposition, and the decorative layer is also applied to the carrier layer by physical vapor deposition. The layer thickness of the carrier layer can be between 0.01 and 0.3 x 10-6 m.
[0034] Advantageously, the outer side to be provided with the layer can be processed in a polishing device outside the PVD coating system before the layers are applied in the PVD coating system in order to provide a desired surface quality, in particular roughness.
[0035] Short description of the drawing
[0036] The drawing shows an exemplary embodiment of the invention. It shows:
[0037] Fig. 1 shows a section of a base of a cookware with a decorative layer;
[0038] Fig. 2 shows a section of a base of a cooking utensil with a decorative layer applied to a carrier layer;
[0039] Fig . 3 shows a section of a base of a cooking utensil with a further decorative layer .
[0040] Fig. 4 is a view of a cookware with a decorative layer according to the invention.
[0041] From example
[0042] Fig. 1 shows a section of a cooking utensil for heating food, wherein the section represents a base or a wall connected to the base and extending upwards from the base. Both the base and the wall of a cooking utensil are formed by a single- or multi-layer molded body 1. A multi-layer molded body may be useful to improve the heat conduction properties or the durability.
[0043] In the exemplary embodiment, a section of a single-layer molded body 1 made of die-cast aluminum or steel is shown as the base of a cooking utensil. The molded body is not shown as a wall because the construction is similar. The upper side of the molded body 1 in the illustration is an inner side 2 of a cooking utensil on which the food to be heated is arranged (not shown). The lower side of the molded body 1 in the illustration is an outer side 3 of the cooking utensil, in particular for placing on a heat source.
[0044] The outer side 3 is provided with a decorative layer 4. The decorative layer 4 was applied by physical vapor deposition using titanium as a diffuser. A coating produced by physical vapor deposition is generally referred to as a PVD layer.
[0045] In the exemplary embodiment, the decorative layer 4 consists of titanium in metallic form and has a layer thickness of 0.05 - 1.5 x 10-6 m. The decorative layer 4 has a surface 5, which creates the decorative properties of the cookware.
[0046] The decorative layer 4 made of titanium in metallic form has a colour similar to that of steel , in particular polished stainless steel .
[0047] It can be seen that the inner side 2 does not have a layer.
[0048] However, this is not essential for the invention; the inside can also be coated.
[0049] The surface roughness of the outer side 3 of the shaped body 1 before coating is 3 x 10- 6 m in the exemplary embodiment and the decorative layer reflects 70% of the incident visible light by direct reflection.
[0050] In an embodiment not shown, according to the embodiment shown in Fig. 1, the decorative layer 4 consists of chromium and has an SCI color value 10 ° D65 according to Cielab with L* from 60 to 65, a* from - 1 to 1 and b* from 4 to 5.
[0051] In Fig. 2, the outer side 3 is provided with a first layer, namely a carrier layer 6, on which a second layer, namely the decorative layer 4, is arranged. The carrier layer 6 and the decorative layer 4 were applied by physical vapor deposition using titanium as a scattering agent. A coating produced by physical vapor deposition is generally referred to as a PVD layer.
[0052] In the exemplary embodiment, the carrier layer 6 consists of titanium in metallic form and has a layer thickness of 0.1 x 10- 6 m.
[0053] The decorative layer 6 consists of titanium in bonded form with nitrogen, referred to as TiN, and carbon, referred to as TiC, or both, referred to as TiCN.
[0054] The decorative layer 5 made of titanium in bonded form with nitrogen and carbon has a colour similar to copper, but can also be interpreted as a gold tone merging into red.
[0055] Fig. 3 shows that titanium carbonitride TiCN can comprise several very hard, but also very brittle TiC or TiCN layers, which are separated from one another by more ductile TiN layers. The latter can temporarily absorb and distribute stresses. This makes it possible to provide a layered composite consisting of the carrier layer made of Ti, a first layer 4.1 made of TiN and a second layer 4.2 made of TiC, wherein the first and second layers 4.1, 4.2 form the decorative layer 4.
[0056] The surface roughness of the outer side 3 of the shaped body 1 before coating is 3 x 10- 6 m in the exemplary embodiment and the decorative layer reflects 70% of the incident visible light by direct reflection.
[0057] Fig. 4 shows a cooking utensil in the form of a pan with a decorative coating according to the invention. The coating is applied to the outside of a wall 7 and to the outside of a base 8 and is not particularly highlighted in the illustration. A handle 9 extends from the wall 7.
[0058] A color like copper or rose gold can be achieved with a coating of Ti, TiN, TiCn or with a coating of Ti, TiAlN.
[0059] A color like stainless steel can be achieved with a coating of Ti, Cr, CrN, Zr or with a combination of two or three metals selected from Ti, Cr, Zr.
[0060] A black color can be achieved with a coating of Ti, TiC or Cr, Cr3C2, or W, WC or with a combination of two or three metals selected from Ti, Cr, W.
[0061] The decorative layer is created in a PVD coating system. For example, in a first step, the cookware is placed in a chamber of a physical vapor deposition coating system and cleaned.
[0062] In a second step, an outer surface of the base and / or wall is coated with a carrier layer of metallic titanium by physical vapor deposition, using, for example, titanium as a scattering agent. A neutral gas is used.
[0063] In a third step, the carrier layer is coated with a decorative layer of either metallic titanium or titanium in bound form with nitrogen and carbon using a reactive gas such as nitrogen or C2H2 by physical vapor deposition using titanium as a scattering body.
[0064] Advantageously, before the first step, the outer surface can be cleaned with ultrasound and dried, preferably in an oven.
[0065] The advantages of PVD coating can be summarized as follows:
[0066] - color-stable coating, no changes when heated to high temperatures;
[0067] - high adhesion between coating film and substrate (here the outside of the molded body);
[0068] - high density of the coating film;
[0069] - high hardness of the coating film;
[0070] - scratch-resistant;
[0071] - easy cleaning of the surface;
[0072] - environmentally friendly coating processes;
[0073] - food-safe coating film made of titanium.
[0074] The structure, composition, thickness, hardness, adhesion, corrosion resistance and scratch resistance can be determined by conventional tests.
Claims
Patent claims 1. Cookware with a decorative coating, comprising a base (8) and a wall (7) connected to the base (8) and extending vertically away from the base (8), wherein at least part of an outer side (3) of the base and / or an outer side of the wall has a decorative layer (4), characterized in that at least part of an outer side (3) of the base and / or an outer side (3) of the wall is made of die-cast aluminum or carbon steel and that the decorative layer (5) comprises one or more metals selected from titanium or chromium or zirconium or tungsten in metallic form and is produced by physical vapor deposition.
2. Cookware according to claim 1, characterized in that the decorative layer (4) consists of titanium in metallic form and of titanium in combination with nitrogen and of titanium in combination with nitrogen and carbon.
3. Cookware according to claim 1, characterized in that the decorative layer (4) consists of titanium in metallic form and of titanium and aluminum in combination with nitrogen.
4. Cookware according to claim 1, characterized in that the decorative layer (4) consists of chromium in metallic form and of chromium in combination with nitrogen.
5. Cookware according to claim 1, characterized in that the decorative layer (4) consists of titanium and chromium, titanium and zirconium, chromium and zirconium or titanium, chromium and zirconium in metallic form.
6. Cookware according to claim 1, characterized in that the decorative layer (4) consists of titanium in metallic form and of titanium in combination with carbon. REVISED SHEET (RULE 91) ISA / EP 7. Cookware according to claim 1, characterized in that the decorative layer (4) consists of chromium in metallic form and of chromium in combination with carbon.
8. Cookware according to claim 1, characterized in that the decorative layer (4) consists of tungsten in metallic form and of tungsten in combination with carbon.
9. Cookware according to claim 1, characterized in that the decorative layer (4) consists of titanium and chromium, titanium and tungsten, chromium and tungsten or titanium, chromium and tungsten, each in combination with carbon.
10. Cookware according to claim 1, characterized in that the decorative layer (4) is applied by physical vapor deposition using a scattering body made of either titanium or chromium or tungsten or zirconium or titanium and aluminum or a combination of these metals.
11. Cookware according to one of claims 1 to 10, characterized in that the decorative layer (4) has a layer thickness of 0.05 - 1.5 x 10-6 m.
12. Cookware according to one of claims 1 to 11, characterized in that the decorative layer (4) is applied directly to the outside of the base and / or the wall.
13. Cookware according to one of claims 1 to 11, characterized in that the outer side of the base and / or the wall has a metallic carrier layer (6) made of one or more metals selected from titanium or chromium or zirconium or tungsten, wherein the decorative layer (4) is applied to the carrier layer (6).
14. Cookware according to one of claims 1 to 13, characterized in that the surface roughness of the outer side (3) the floor and / or wall before coating not more than 20 x IGF 6 m.
15. Cookware according to one of claims 1 to 14, characterized in that the decorative layer (4) reflects at least 50% of the incident visible light by direct reflection, preferably at least 70%.
16. Cookware according to claim 4, characterized in that the decorative layer (4) has an SCI color value 10° D65 according to Cielab with L* of 55 to 80, a* of -2 to 3 and b* of -3 to 7.
17. Cookware according to claim 16, characterized in that the decorative layer (4) has an SCI color value 10° D65 according to Cielab with L* of 60 to 65, a* of -1 to 1 and b* of 4 to 5.
18. A method for producing a cookware item made of an aluminum alloy or carbon steel with a decorative layer (4) which is produced by physical vapor deposition, the cookware item having a base (8), in particular for placing on a heat source, and a wall (7) connected to the base (8) and extending upwards from the base (8), characterized in that an outer side (3) of the base and / or the wall is at least partially coated with a decorative layer (4) made of metal by physical vapor deposition, one or more metals selected from titanium or chromium or zirconium or tungsten in metallic form being used to produce the decorative layer made of metal.
19. Method according to claim 18, characterized in that before applying the decorative layer, the outside of the floor and / or the wall is covered with a carrier layer selected from zirconium, titanium, chromium and tungsten in metallic form or a combination of two or more of these metals, wherein the carrier layer is applied by physical vapor deposition and wherein the decorative layer is also applied to the carrier layer by physical vapor deposition. 20 . Method according to claim 5 , characterized in that the outer side to be provided with the decorative layer is machined outside the PVD coating plant before the application of the layers in the PVD coating plant in order to achieve a roughness of at most 20 x 10~ 6 m to provide .