Baking tray or baking grid having a non-stick and/or non-wetting coating, cooking appliance comprising such a baking tray or baking grid and method for manufacturing a baking tray or baking grid

Patent metadata

Field	Value
Publication number	US-12290076-B2
Application number	US-202017776841-A
Country	US
Kind code	B2
Filing date	Sep 29, 2020
Priority date	Nov 15, 2019
Publication date	May 6, 2025
Grant date	May 6, 2025

Abstract

The present invention relates to a baking tray ( 20 ) or baking grid, in particular a baking tray ( 20 ) for a cooking appliance ( 1 ), having a non-stick and/or non-wetting coating ( 12 ) obtainable by a process characterised by the following steps, a) providing a baking tray ( 20 ) or baking grid having a surface, in particular having an upper surface ( 7 a ) and a bottom surface ( 7 b ), b) preferably, pretreating of the surface ( 7 a, 7 b ) of the baking tray ( 20 ) or baking grid at least partially, in particular completely, for providing a surface having a roughness being suitable for applying a non-stick and/or non-wetting coating ( 12 ) by mechanical treatment, physical treatment or chemical treatment, in particular by sandblasting and/or laser treatment and/or a surface activation treatment, particularly a plasma treatment, and/or an enameling process to form a ground layer ( 13 ), c) applying the non-stick and/or non-wetting coating ( 12 ) to the pretreated surface ( 7 a, 7 b ) of the baking tray ( 20 ) or baking grid or a surface ( 14 a ) of the ground layer ( 13 ), wherein the non-stick and/or non-wetting coating ( 12 ) comprises at least one layer ( 17 ) that is obtained by a sol-gel process from a first composition comprising a silica sol and a silane. The invention further relates to a cooking appliance ( 1 ), in particular a domestic oven comprising such a baking tray ( 20 ) or baking grid and a method for manufacturing such a baking tray ( 20 ) or baking grid.

First claim

The invention claimed is:

1. A coated baking tray or baking grid having a non-stick and/or non-wetting coating produced by a process comprising the following steps:
a) providing a baking tray or baking grid having an upper surface and a lower surface,
b) pretreating the surface upper surface and/or the lower surface of the baking tray or baking grid to yield a pretreated baking tray or baking grid having a surface with a surface roughness suitable for applying a non-stick and/or non-wetting coating, the baking tray or baking grid being pretreated by mechanical treatment, physical treatment, or chemical treatment,
c) applying the non-stick and/or non-wetting coating to the surface of the pretreated baking tray or baking grid, wherein the non-stick and/or non-wetting coating comprises at least one layer that is obtained by a sol-gel process from a first composition comprising a silica sol and a silane,
wherein the baking tray or baking grid is pretreated to form a ground layer, the ground layer being an enamel layer having a layer thickness between 10 and 80 μm.

2. The coated baking tray or baking grid according to claim 1 , wherein the baking tray or baking grid is made of a corrosive material or a non-corrosive material.

3. The coated baking tray or baking grid according to claim 1 , wherein the step of pretreating the baking tray or baking grid includes applying a protective layer to the upper surface and/or the lower surface of the baking tray or baking grid, and pretreating said protective layer by sandblasting and/or laser treatment such that the protective layer provides the surface having a roughness suitable for applying the non-stick and/or non-wetting coating.

4. The coated baking tray or baking grid according to claim 3 , wherein the protective layer is an enamel layer and/or an aluminium layer and/or a layer comprising aluminium.

5. The coated baking tray or baking grid according to claim 3 , wherein the protective layer has a thickness between 50 and 250 μm.

6. A coated baking tray or baking grid having a non-stick and/or non-wetting coating produced by a process comprising the following steps:
a) providing a baking tray or baking grid ha an upper surface and a lower surface,
b) pretreating the surface upper surface and/or the lower surface of the baking tray or baking grid to yield a treated baking tray or baking grid having a surface with a surface roughness suitable for applying a non-stick and/or non-wetting coating, the baking tray or baking grid being pretreated by mechanical treatment, physical treatment, or chemical treatment,
c) applying the non-stick and/or non-wetting coating to the surface of the pretreated baking tray or baking grid, wherein the non-stick and/or non-wetting coating comprises at least one layer that is obtained by a sol-gel process from a first composition comprising a silica sol and a silane,
wherein the surface of the pretreated baking tray or baking grid has a surface roughness between Ra 0.01 μm to 10.00 μm.

7. The coated baking tray or baking grid according to claim 1 , wherein the non-stick and/or non-wetting coating comprises at least a first layer and a second layer, wherein the first layer of the non-stick and/or non-wetting coating is applied to the surface of the pretreated baking tray or baking grid, and wherein the second layer of the non-stick and/or non-wetting coating is applied to the first layer of the non-stick and/or non-wetting coating.

8. The coated baking tray or baking grid according to claim 7 , wherein the second layer of the non-stick and/or non-wetting coating is obtained by a sol-gel process from a second composition comprising a silica sol, a silane and a siloxane.

9. The coated baking tray or baking grid according to claim 1 , wherein the silica sol is present in an amount of 15 to 70 wt % and/or the silane is present in an amount of 2 to 70 wt %, within the first composition.

10. A coated baking tray or baking grid having a non-stick and/or non-wetting coating produced by a process comprising the following steps:
a) providing a baking tray or baking grid having an upper surface and a lower surface,
b) pretreating the surface upper surface and/or the lower surface of the baking tray or baking grid to yield a pretreated baking tray or baking grid having a surface with a surface roughness suitable for applying a non-stick and/or non-wetting coating, the baking tray or baking grid being pretreated by mechanical treatment, physical treatment, or chemical treatment,
c) applying the non-stick and/or non-wetting coating to the surface of the pretreated baking tray or baking grid, wherein the non-stick and/or non-wetting coating comprises at least one layer that is obtained by a sol-gel process from a first composition comprising a silica sol and a silane,
wherein the silane is an organoalkoxysilane and/or a fluoralkoxysilane.

11. The coated baking tray or baking grid according to claim 1 , wherein the first composition comprises an organic solvent, and/or an acidic catalyst.

12. The coated baking tray or baking grid according to claim 11 , wherein the solvent is present in said first composition in an amount of 10 to 60 wt %, and/or the catalyst is present in said first composition in an amount of 0.1 to 5 wt %.

13. A coated baking tray or baking grid having a non-stick and/or non-wetting coating produced by a process comprising the following steps:
a) providing a baking tray or baking grid having an upper surface and a lower surface,
b) pretreating the surface upper surface and/or the lower surface of the baking tray or baking grid to yield pretreated baking tray or baking grid having a surface with a surface roughness suitable for applying a non-stick and/or non-wetting coating, the baking tray or baking grid being pretreated by mechanical treatment, physical treatment, or chemical treatment,
c) applying the non-stick and/or non-wetting coating to the surface of the pretreated baking tray or baking grid, wherein the non-stick and/or non-wetting coating comprises at least one layer that is obtained by sol-gel process from a first composition comprising a silica sol and a silane,
wherein the first composition comprises a siloxane.

14. The coated baking tray or baking grid according to claim 8 , wherein the siloxane is present in said first composition in an amount of 0.1 to 2 wt %.

15. The coated baking tray or baking grid according to claim 1 , wherein the first composition comprises pigments and/or dyes and/or filling materials and/or further additives.

16. The coated baking tray or baking grid according to claim 1 , wherein at least a part of an outer surface of the non-stick and/or non-wetting coating provides an activated surface area activated by an activation process that increases surface tension within the activated surface area using plasma technology, and wherein a printing is applied to the activated surface area by means of ink technology.

17. A cooking appliance comprising:
a heatable cavity, comprising at least one cavity wall defining a cooking chamber for cooking foodstuff and a central opening for placing foodstuff into the cooking chamber,
heating elements for heating said cavity,
a door for closing the central opening of the cavity,
mounting grids and/or shelves disposed at a left cavity wall and a right cavity wall, and the coated baking tray or baking grid according to claim 1 mounted or mountable on said mounting grids and/or shelves.

18. A method for manufacturing a coated baking tray or baking grid of a cooking appliance, having a non-stick and/or non-wet

Assignees

• Electrolux Appliances AB

Inventors

• Schütz Tobias
• Tisselli Filippo
• Wälzlein Klaus

Classifications

• F24C15/12

  Side rests; Side plates; Cover lids; Splash guards; Racks outside ovens, e.g. for drying plates · CPC title

• C23C28/345

  with at least one oxide layer · CPC title

• C23C28/321

  with at least one metal alloy layer · CPC title

• F24C15/005

  Coatings for ovens · CPC title

• C23D5/04

  by dry methods · CPC title