Sol-gel coating comprising anisotropic particles and culinary article provided with such a coating

Patent metadata

Field	Value
Publication number	US-9814349-B2
Application number	US-201314373789-A
Country	US
Kind code	B2
Filing date	Jan 18, 2013
Priority date	Jan 25, 2012
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

Provided is a vitreous coating comprising at least one layer embodied in the form of a continuous film of sol-gel material comprising a matrix formed from at least one metal polyalkoxylate and wherein anisotropically-shaped particles are dispersed, said layer comprising at least one area wherein the particles are particles predominantly inclined by an angle (α) of between 20° and 90° relative to the median plane of the film. The subject matter of the present invention also comprises a method of manufacturing such a coating, and a culinary article one of the surfaces of which is coated with such a coating.

First claim

The invention claimed is:

1. Vitreous coating comprising at least one layer in the form of a continuous film of a sol-gel material comprising a matrix formed from at least one metallic polyalkoxylate and in which anisotropic shaped particles are dispersed, said layer comprising at least one first area in which said particles are particles which are inclined at an angle α between 20° and 90° with respect to the average plane of the film,
wherein more than 66% of said anisotropic shaped particles are inclined at an angle α between 20° and 90° with respect to the average plane of the film, and
wherein said coating further comprises, adjacent to the first area, at least one second area in which more than 66% of the particles are particles which are inclined at an angle β that is greater than 0° and less than 20° with respect to the average plane of the film.

2. Coating according to claim 1 , wherein more than 80% of said anisotropic shaped particles are inclined at an angle α between 20° and 90° with respect to the average plane of the film.

3. Coating according to claim 1 , wherein said particles comprise particles capable of being oriented by mechanical or physical means.

4. Coating according to claim 3 , wherein said particles capable of being oriented are magnetisable particles.

5. Coating according to claim 4 , wherein said magnetisable particles comprise at least one ferromagnetic metal.

6. Coating according to claim 5 , wherein the magnetisable particles have a core-shell structure, in which the ferromagnetic metal is in the core and/or in the shell of said particles.

7. Coating according to claim 6 , wherein the magnetisable particles are mica flakes encapsulated with iron oxide Fe 2 O 3 .

8. Coating according to claim 6 , wherein the magnetisable particles are flakes whose core is made of a plastic material and the shell is made of iron oxide Fe 2 O 3 , or flakes or fibres whose core is made of ferromagnetic metal and the shell is made of a plastic material or of a sol-gel material.

9. Coating according to claim 4 , wherein said vitreous coating layer further comprises non-magnetisable particles.

10. Coating according to claim 9 , wherein the magnetisable particles, and the non-magnetisable particles, have a core-shell structure.

11. Coating according to claim 9 , wherein the non-magnetisable particles are selected from the group comprising mica flakes, and titanium dioxide encapsulated mica or silica flakes.

12. Coating according to claim 4 , wherein the magnetisable particles are ferritic stainless steel fibres.

13. Coating according to claim 1 , wherein more than 80% of said particles are, in the second area, inclined at an angle β lower than 20° with respect to the average plane of the film.

14. Coating according to claim 1 , said coating being non-opaque and further comprising, adjacent to the first area, at least one second area in which the particles are randomly arranged in the layer in the form of a film.

15. Coating according to claim 1 , wherein the alternation of the first and second areas defines a decor.

16. Coating according to claim 1 , said coating being a finish layer.

17. Coating according to claim 1 , comprising:
a base layer intended to be arranged on a support, and
at least one finish layer covering said base layer and intended to be in contact with the outside environment, said finish layer being in the form of a continuous film of a sol-gel material comprising a matrix formed from at least one metallic polyalkoxylate in which said anisotropic particles are dispersed.

18. Coating according to claim 17 , wherein said base layer is also in the form of a continuous film of a sol-gel material, the sol-gel material preferably comprising a matrix formed from at least one metallic polyalkoxylate.

19. Coating according to claim 17 , wherein said base layer is a continuous or discontinuous hard base, said hard base being made of one of enamel, of ceramic, or of metal.

20. Coating according to claim 17 , wherein the metallic polyalkoxylate of the finish layer, and of the base layer, is a polyalkoxysilane.

21. Coating according to claim 20 , wherein the film of sol-gel material of the finish layer, and of the base layer, further comprises at least 5% by weight with respect to the total coating weight of at least one colloidal metallic oxide dispersed in said matrix, said oxide being selected from the group comprising silica, alumina, cerium oxide, zinc oxide, vanadium oxide and zirconium oxide.

22. Coating according to claim 1 , wherein the sol-gel material forming said vitreous coating further comprises at least one silicone oil.

23. Coating according to claim 22 , wherein the silicone oil is selected from methyl-phenyl silicone oils, methyl silicone oils and hydroxylated silicone oils.

24. Coating according to claim 1 , wherein said vitreous coating comprises at least one pigment selected from the thermostable pigments, the metallic salts, the thermochromic semiconductor pigments, and mixtures thereof.

25. Article comprising a support having two opposite sides, at least one of which is covered with a coating as defined in claim 1 .

26. Article according to claim 25 , wherein the support is made of a material selected from metals, wood, glass, ceramics and plastic materials.

27. Article according to claim 26 , wherein the support is a metallic support made of one of anodised or non-anodised aluminium, or of polished, brushed, or micro-shotpeened aluminium, or of polished, brushed or micro-shotpeened stainless steel, or of cast iron, or of hammered or polished copper.

28. Article according to claim 25 , which is a culinary article, or a sole plate of an electric iron, or plates of hair straighteners, or a hood of a household appliance.

29. Method for manufacturing a vitreous coating according to claim 1 on a support in which anisotropic particles are dispersed, comprising a step of orienting said anisotropic particles by physical or mechanical means in at least one area of said vitreous coating according to claim 1 .

30. Method according to claim 29 , comprising the following steps:
a) providing the support;
b) preparing a hybrid composition comprising at least one metallic alkoxide type sol-gel precursor and anisotropic shaped particles;
c) hydrolysing said sol-gel precursor by introduction of water and of an acid or basic catalyst, followed by a condensation reaction to obtain a sol-gel composition SG;
(d) maintaining the support at a temperature lower than or equal to 100° C. followed by applying, directly or indirectly on all or part of the support, at least one layer of sol-gel composition SG;
e) orienting said anisotropic particles by physical or mechanical means in at least one area of said SG composition layer; then
f) firing.

31. Method according to claim 30 , wherein said anisotropic shaped particles are magnetisable particles, and
in step e) of orienting said magnetisable particles is a step of magnetisation by applying a magnetic field, said magnetisation e) being carried out either during the application d) of the sol-gel composition SG on the support, or after said application step d) and prior to the firing step f).

32. Method according to claim 31 , wherein a sol-gel composition SG essentially free of opaque pigments is prepared, so tha

Assignees

• Seb Sa

Inventors

• Dubanchet Aurelien
• Le Bris Stephanie
• Perillon Jean-Luc

Classifications

• Y10T428/31612

  As silicone, silane or siloxane · CPC title

• Y10T428/24612

  Composite web or sheet · CPC title

• A47J36/02 Primary

  Selection of specific materials, e.g. heavy bottoms with copper inlay or with insulating inlay · CPC title

• Y10T428/31663

  As siloxane, silicone or silane · CPC title

• B05D5/08

  to obtain an anti-friction or anti-adhesive surface (rendering particulate materials free-flowing in general, e.g. making them hydrophobic B01J2/30) · CPC title