DE102023119963A1 - Cookware with a decorative layer and method for producing a decorative layer - Google Patents

Abstract

A cookware with a decorative coating has a base and a wall connected to the base and extending upwards from the base, wherein at least a part of an outer side 3 of the base and/or an outer side of the wall has a decorative layer 4. At least a part of an outer side 3 of the base and/or an outer side 3 of the wall consists of aluminum alloy or of carbon steel and the decorative layer 4 is applied by physical vapor deposition using chromium as a scattering body and consists of metallic chromium.
In a method for producing a decorative layer, the decorative layer is produced by physical vapor deposition of metallic chromium.

Description

technical field

The invention relates to a cooking utensil with a decorative coating for heating food, having a base, in particular for placing on a heat source, and a wall connected to the base and extending upwards from the base. Such cooking utensils are, for example, a pot, a pan, a roasting pan or a saucepan.

State of the art

From the 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 flame exposure is avoided. The coating is applied to a carrier metal that has been polished to a high gloss, such as stainless steel, carbon steel, titanium or similar.

The use of chromium to provide a multi-layer PVD coating with a decorative appearance similar to stainless steel is US 2014/0242413 A1 A layer of Zr-Cr-X is used, where X can be carbon, nitrogen or oxygen.

The object of the invention is to provide a cookware with a decorative coating.

representation of the invention

In a cookware according to the invention with a decorative coating, having 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 consists of an aluminum alloy or of carbon steel and the decorative layer is applied by physical vapor deposition using chromium as a scattering body (target). The decorative layer consists of chromium in metallic form.

Carbon steel, also called carbon steel, is steel that contains carbon as a secondary component in addition to its main component iron. Since "C" is the chemical symbol for carbon, carbon steel is also called C-steel. The carbon content can be up to 2.1%.

Aluminium alloys are alloys that consist predominantly of aluminium, as aluminium can be alloyed with numerous metals. There are wrought aluminium alloys that are intended for further processing by rolling, forging and extrusion, and cast materials that are used in foundries. In general, aluminium alloys are therefore divided into wrought and cast alloys.

Advantageously, the base and/or the wall together with the decorative layer can have a hardness of 80 to 180 HV/0.1/10. This allows a considerable increase in hardness to be achieved, particularly in the case of an aluminium alloy.

Advantageously, the decorative layer can have a layer thickness of 0.05 - 0.5 × 10-6 m.

It has been found that the inside of the base and the wall can be free of a layer created by physical vapor deposition. Alternatively, a known coating, such as a non-stick coating, can be applied.

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.

The decorative layer can advantageously have an SCI color value of 10° D65 according to Cielab with L* of 55 to 80, a* of -2 to 3 and b* of -3 to 7. This gives the cookware a look similar to stainless steel without the disadvantageous cooking properties of stainless steel. Cielab color measurement according to the SCI method includes the gloss components, using the light type D65 and an angle of incidence of 10°.

It can be particularly advantageous if the decorative layer has an SCI colour value of 10° D65 according to Cielab with L* from 60 to 65, a* from -1 to 1 and b* from 4 to 5.

Furthermore, the decorative layer can 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 before applying the decorative layer or the carrier layer.

Another object of the invention is a method for producing a cookware made of an aluminum alloy or of carbon steel with a decorative layer which is produced by physical vapor deposition, wherein the cookware has a base, in particular for placing on a heat source, and a wall connected to the base and extending upwards from the base.

An outer side of the base and/or the wall is at least partially coated with a decorative layer of metallic chromium by physical vapor deposition using chromium as a scattering body.

Before this coating, the cookware is placed in a chamber of a coating system for physical vapor deposition and can be cleaned.

Furthermore, before insertion, the outer surface can be cleaned with ultrasound and dried, preferably in an oven.

It is also possible to process the outside to be provided with the layer in a polishing device outside the PVD coating system before applying the layers in the PVD coating system in order to provide a desired surface quality, in particular roughness. The processing can be carried out in such a way that the surface roughness of the outer surface of the base and/or the wall before coating is at most 20 * 10-6 m, preferably 0.5 * 10-6 m to 3 * 10-6 m.

Short description of the drawing

• 1 einen Ausschnitt aus einem Boden eines Kochgeschirrs mit einer dekorativen Schicht;
• 2 eine Ansicht eines Kochgeschirrs mit einer erfindungsgemäßen dekorativen Schicht.

An embodiment of the invention is shown in the drawing. It shows:

• 1 a section of a bottom of a cookware with a decorative layer;
• 2 a view of a cookware with a decorative layer according to the invention.

embodiment

In 1 a section of a cooking vessel for heating food is shown, the section representing a base or a wall connected to the base and extending upwards from the base. Both the base and the wall of a cooking vessel can be formed by a single-layer or multi-layer molded body. A multi-layer molded body can be useful in order to improve the heat conduction properties or the durability.

In the exemplary embodiment, a section of a single-layer molded body 1 made of an aluminum alloy or carbon steel is shown as the base of a cooking vessel. The molded body is not shown as a wall because the structure corresponds to the decorative layer. The upper side of the molded body 1 in the illustration is an inner side 2 of a cooking vessel 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 vessel, in particular for placing on a heat source.

The outer side 3 is provided with a decorative layer 4. The decorative layer 4 was applied by physical vapor deposition using chromium as a scattering agent. A coating produced by physical vapor deposition is generally referred to as a PVD layer.

The decorative layer 4 consists of chromium in metallic form and has a layer thickness of 0.05 - 0.5 × 10-6 m.

The molded body 1 with the decorative layer 4 has a hardness of 80 - 180 HV/0.1/10. The hardness was measured according to Vickers.

It can be seen that the inner side 2 does not have a coating. However, this is not essential for the invention; the inner side can also be coated.

The surface roughness of the outer side 3 of the molded body 1 before coating is 3 × 10-6 m in the embodiment and the decorative layer reflects 70% of the incident visible light by direct reflection.

The decorative layer 4 of chromium in metallic form has a colour similar to that of steel, in particular polished stainless steel.

In 2 a cooking vessel in the form of a pan with a decorative layer according to the invention is shown. The coating is applied to the outside of a wall 5 and to the outside of a base 6 and is not particularly highlighted in the illustration. A handle 7 extends away from the wall 5.

• - farbstabile Beschichtung, keine Änderungen beim Erhitzen auf hohe Temperaturen;
• - hohe Adhäsion zwischen Beschichtungsfilm und Substrat (hier die Außenseite des Formkörpers);
• - hohe Dichte des Beschichtungsfilms;
• - hohe Härte des Beschichtungsfilms;
• - kratzunempfindlich;
• - leichte Reinigung der Oberfläche;
• - umweltfreundlich Beschichtungsprozesse.

The advantages of PVD coating can be summarized as follows:

• - color-stable coating, no changes when heated to high temperatures;
• - high adhesion between coating film and substrate (here the outside of the molded body);
• - high density of the coating film;
• - high hardness of the coating film;
• - scratch-resistant;
• - easy cleaning of the surface;
• - environmentally friendly coating processes.

The structure, composition, thickness, hardness, adhesion, corrosion resistance and scratch resistance can be determined by conventional tests.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• EP 0 966 910 B1 [0002]
• US 2014/0242413 A1 [0003]

Claims (8)

Cookware with a decorative coating, comprising a base and a wall connected to the base and extending upwards from the base, wherein at least part of an outer side (3) of the base and/or an outer side of the wall has a decorative layer (5), characterized in that at least part of an outer side (3) of the base and/or an outer side (3) of the wall consists of an aluminum alloy or of carbon steel and that the decorative layer (5) is applied by physical vapor deposition using chromium as a scattering body, wherein the decorative layer (5) consists of chromium in metallic form. Cookware after claim 1 , characterized in that the base and/or the wall together with the decorative layer (5) has a hardness of 80 to 180 HV/0.1/10. Cookware according to one of the Claims 1 until 2 , characterized in that the decorative layer has a layer thickness of 0.05 - 0.5 × 10 ^-6 m. Cookware according to one of the Claims 1 until 3 , characterized in that the surface roughness of the outer side (3) of the base and/or the wall before coating is at most 20 × 10 ^-6 m. Cookware according to one of the Claims 1 until 4 , characterized in that the decorative layer has an SCI colour value 10° D65 according to Cielab with L* from 55 to 80, a* from -2 to 3 and b* from -3 to 7. Cookware after claim 5 , characterized in that 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. Method for producing a cookware made of an aluminum alloy or of carbon steel with a decorative layer which is produced by physical vapor deposition, wherein the cookware has a base, in particular for placing on a heat source, and a wall connected to the base and extending upwards from the base, characterized in that an outer side of the base and/or the wall is at least partially coated with a decorative layer of metallic chromium by physical vapor deposition using chromium as a scattering body. procedure according to claim 7 , characterized in that the outer side to be provided with the decorative layer is machined outside the PVD coating plant before the layers are applied in the PVD coating plant in order to provide a roughness of at most 20 × 10 ^-6 m.

Images