Coated glass or glass ceramic substrate with haptic properties

Abstract

Disclosed are articles that are provided with a haptically-perceptible surface. The articles include a coated glass or glass ceramic substrate which is provided with a layer with haptic properties so that the layer has a haptically perceptible texture. The layer includes texturing inorganic and/or polysiloxane-based particles which are fixed on the substrate by a layer-forming material. The particles cause protrusions on the layer and so produce the haptically perceptible texture.

Claims

1. A coated glass or glass ceramic substrate, comprising: a substrate; a layer covering an area of said substrate, the layer being comprised of a layer-forming material including at least partially melted glass flow particles and texturing particles, the texturing particles having a melting point above a burning-in temperature of the layer-forming material so that the texturing particles are embedded in the layer in a manner that retains an initial outer contour of the texturing particles with the texturing particles partially protruding from the layer, the layer-forming material comprising in wt. % Al.sub.2O.sub.3 0-25 and SiO.sub.2 6-65, wherein the texturing particles are polysiloxane-based particles, wherein the layer has an average layer thickness at locations without the texturing particles that ranges from about 0.1 m to about 20 m, wherein the texturing particles produce a haptically perceptible texture that has a surface roughness value from 0.2 m to 1.2 m, and wherein the initial outer contour of the texturing particles comprise substantially edgeless and/or rounded outer contours to cause a velvety perception of the layer.

2. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer-forming material is a matrix selected from the group consisting of: organic matrix, inorganic matrix, polysiloxane-based matrix, silazane-based matrix, glass-based layer-forming matrix, and any combination thereof.

3. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer-forming material exhibits a temperature resistance of more than about 150 C.

4. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer has a characteristic-selected from the group consisting of: the visible degree of surface occupancy of texturing particles protruding from the layer-forming material is greater than about 5%; the volume ratio of layer-forming material to texturing particles is greater than about 0.1; the mass ratio of layer-forming material to texturing particles ranges from about 20 to about 0.1; the average spacing of texturing particles, based on the spacing from particle center to particle center, is smaller than about 4 times the mean particle diameter of the texturing particles; the average layer thickness ranges from about 0.5 m to about 50 m; and any combination thereof.

5. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the texturing particles cause protrusions to form on the layer-forming material in an amount selected from the group consisting of: partially protruding from the layer-forming material, not covered with the layer-forming material, partially covered with the layer-forming material, and any combination thereof.

6. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the average layer thickness of the layer-forming material is smaller than the mean diameter of the texturing particles.

7. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the peak-to-valley (PV) value of a layer that comprises edgeless spherical particles ranges from about 4 to about 10 m.

8. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said texturing particles further comprise materials selected from the group consisting of: glasses, alkali aluminosilicate glasses and any combination thereof.

9. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said texturing particles further comprise oxidic materials.

10. The coated glass or glass ceramic substrate as claimed in claim 9, wherein said oxidic material is selected from the group consisting of: Al.sub.2O.sub.3, crystalline SiO.sub.2, ZrO.sub.2, ZrSiO.sub.4, ZnAl.sub.2O.sub.4, MgAl.sub.2O.sub.4, Y.sub.2O.sub.3, yttrium-doped ZrO.sub.2, calcium-doped ZrO.sub.2, magnesium-doped ZrO.sub.2, TiO.sub.2, ZnO, and any combination thereof.

11. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said texturing particles further comprise at least some particles having a softening range below the burning-in temperature of the layer-forming material and an initial contour that is spherical or edgeless so as to be embedded in the layer in partially melted form as fragments of the initial contour, the fragments having edges and points that protrude from the layer.

12. The coated glass or glass ceramic substrate as claimed in claim 11, wherein at least some of the texturing particles having the softening range below the burning-in temperature of the layer-forming material comprise an initial edged and/or polygonal outer contour.

13. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the texturing particles have a softening range above about 1000 C.

14. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the texturing particles are spherical particles.

15. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the layer-forming material further comprises a filler.

16. The coated glass or glass ceramic substrate as claimed in claim 15, wherein the filler comprises: pigments, dyes, additives, and any combination thereof.

17. The coated glass or glass ceramic substrate as claimed in claim 16, wherein the mass fraction of said filler in the total mass of the layer-forming material binding the texturing particles ranges from about 0 to about 60 wt. %.

18. The coated glass or glass ceramic substrate as claimed in claim 16, wherein said additive is selected from the group consisting of: TiO.sub.2, spinels, CrCu spinels, Fe spinels, mica, and mica-based effect pigments, and any combination thereof.

19. The coated glass or glass ceramic substrate as claimed in claim 1, having a property selected from the group consisting of: a reflectance at 550 nm from about 6 to about 9%, a transmittance at 550 nm from 75 to 85%, and any combination thereof.

20. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the glass flow particles comprise a glass that is free of lead and cadmium.

21. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the glass flow forming particles have a mean particle diameter, before being at least partially melted, of about 10 m.

22. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer-forming material comprises an organic polymer selected from the group consisting of: polyurethane, polyacrylate, polymethacrylate, polyvinyl alcohol, polyvinyl chloride, polyvinyl acetals, polyvinyl pyrrolidone, polystyrene, epoxy, polyolefins, and mixtures of these constituents, preferably polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, perfluorinated polymers, and any combination thereof.

23. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer-forming material comprises a polysiloxane resin selected from the group consisting of: methylpolysiloxane, phenylpolysiloxane, methylphenylpolysiloxane, vinyl-functionalized polysiloxane resin, allyl-functionalized polysiloxane resin, methacrylic functionalized polysiloxane resin, epoxy-functionalized polysiloxane resin, hydroxyl-functionalized polysiloxane resin, carboxyl-functionalized polysiloxane resin and any combination thereof.

24. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer-forming material comprises inorganic sol-gel material, polymeric sol-gel material, hybrid polymeric sol-gel material and any combination thereof.

25. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said substrate comprises a kitchen element made of glass or glass ceramic, and wherein said layer with texturing particles comprises printing on said kitchen element.

26. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said layer is selected from the group consisting of: local-area printing for a bulk-colored glass ceramic cooktop, full-area printing for a bulk-colored glass ceramic cooktop, local-area printing for color-coated glass ceramic cooktop, bulk-area printing for color-coated glass ceramic cooktop, radiant heating elements, gas cookers, induction cookers, and any combination thereof.

27. The coated glass or glass ceramic substrate as claimed in claim 1 having a property selected from the group consisting of: a haze value of the light reflected at the layer ranges from about 65% to about 90%, a gloss value of the light reflected at the layer ranges from about 15% to about 35%, and any combination thereof.

28. The coated glass or glass ceramic substrate as claimed in claim 1, having a property such that the ratio of the intensity of light transmitted through the substrate and the layer and passing at an angle of 0 to the intensity of light transmitted through the substrate and the layer and scattered at an angle of 10 is at least 2.

29. A glass ceramic cooktop comprising a coated glass or glass-ceramic substrate as claimed in claim 1, wherein said substrate is a transparent glass ceramic panel, having an upper surface coated with said layer having haptic properties, and wherein a display element is arranged at a lower surface of the glass ceramic panel, such that in operation said display element shines through said layer on said upper surface.

30. The coated glass or glass ceramic substrate as claimed in claim 1, wherein said polysiloxane is selected from the group consisting of: phenylpolysiloxane, methylpolysiloxane, methylphenylpolysiloxane, organically functionalized polysiloxanes and any combination thereof.

31. The coated glass or glass ceramic substrate as claimed in claim 20, wherein the glass of the glass flow particles has a composition selected from the group consisting of: TABLE-US-00007 (in wt. %): Li.sub.2O 0-10 Na.sub.2O 0-10 K.sub.2O 0-10 MgO 0-5 CaO 0-5 SrO 0-4 BaO 0-24 ZnO 0-15 B.sub.2O.sub.3 0-29 Al.sub.2O.sub.3 0-25 SiO.sub.2 44-73 TiO.sub.2 0-5 ZrO.sub.2 0-7 As.sub.2O.sub.3 0-1 Sb.sub.2O.sub.3 0-15 F 0-3, (in wt. %): SiO.sub.2 35-65 Al.sub.2O.sub.3 3-18 B.sub.2O.sub.3 5-25 Li.sub.2O 0-12 Na.sub.2O 0-18 K.sub.2O 0-18 CaO 0-17 MgO 0-12 BaO 0-38 SrO 0-16 ZnO 0-38 TiO.sub.2 0-5 ZrO.sub.2 0-3 Bi.sub.2O.sub.3 0 CoO 0 Fe.sub.2O.sub.3 0 MnO 0 Ce0.sub.2 0 F 0, (in wt. %): SiO.sub.2 6-20 Al.sub.2O.sub.3 0-5 B.sub.2O.sub.3 20-38 Li.sub.2O 0-2 Na.sub.2O 0-2 K.sub.2O 0-2 CaO 0-2 MgO 0-2 BaO 0-2 SrO 0-2 ZnO 35-70 TiO.sub.2 0-5 ZrO.sub.2 0-5 Bi.sub.2O.sub.3 0-20 CoO 0-5 Fe.sub.20.sub.3 0-5 MnO 0-10 Ce0.sub.2 0-2 F 0-6 and any combination thereof.

32. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the glass flow forming particles are completely or almost completely melted so that the layer has a meso- and/or micro-porosity that is less than 1 vol. %.

33. The coated glass or glass ceramic substrate as claimed in claim 1, wherein the glass flow forming particles are only partially melted so that the layer has a meso- to micro-porosity with pores having pore radii in a range from 20 to 1000 nm.

34. A coated glass or glass ceramic substrate, comprising: a substrate; a layer comprising texturing particles selected from the group consisting of phenylpolysiloxane, methylpolysiloxane, methylphenylpolysiloxane, organically functionalized polysiloxanes, and any combinations thereof; and a layer-forming material fixing the texturing particles on the substrate, the layer-forming material comprising a glass having, in wt. %, Al.sub.2O.sub.3 0-25 and SiO.sub.2 6-65, the texturing particles having a melting point above a burning-in temperature of the glass so that the texturing particles are embedded in the layer in a manner that retains an initial outer contour of the texturing particles with the texturing particles partially protruding from the layer, wherein the layer has an average layer thickness at locations without the texturing particles that ranges from about 0.1 m to about 20 m, wherein the initial contour of the texturing particles comprises edgeless and/or rounded outer contours sufficient to provide a haptically perceptible velvety texture.

35. The coated glass or glass-ceramic substrate as claimed in claim 34, wherein the glass of the layer-forming material is free of lead and cadmium.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 shows embodiments of locally patterned haptic layers;

(3) FIG. 2 shows a layer having a velvety haptic perception;

(4) FIG. 3 shows a layer having a rough haptic perception;

(5) FIG. 4 shows a cross-sectional SEM image of a layer with a velvety haptic perception;

(6) FIG. 5 shows a cross-sectional SEM image of a layer with a rough haptic perception;

(7) FIG. 6 shows transmission characteristics of different samples in function of the wavelength;

(8) FIG. 7 shows angle-dependent light scattering of different samples;

(9) FIGS. 8 through 10 show optical micrographs of samples.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(10) The following table summarizes various glasses according to the disclosure for producing the glass flow forming particles, and the composition thereof.

(11) TABLE-US-00004 TABLE 4 Composition of inventive glasses in wt. % Wt. % Glass A Glass B Glass C Glass D Glass E Glass F SiO.sub.2 44-57 53-63 57-62 47-52 40-50 63-73 Al.sub.2O.sub.3 5-25 15-25 5-8 2-6 9-15 0-7 B.sub.2O.sub.3 0-27 15-22 18-23 17-21 10-15 12-29 Li.sub.2O 0-10 2-7 2-6 3-5 0-4 0-6 Na.sub.2O 0-10 0-1 0-1 1-5 1-4 0-8 K.sub.2O 0-10 0-1 0-4 5-10 0-3 0-8 CaO 0-4 1-4 1-2 0-2 0-3 0-5 MgO 0-3 1-4 0-2 0-1 0-3 0.1-5.sup. BaO 0-4 0-1 0-2 0-2 16-24 0-5 SrO 0-4 1-4 0.5-2.sup. 0-1 0-2 0-4 ZnO 0-15 1-4 0-2 0-3 8-15 0-15 TiO.sub.2 0-3 0-1 0-2 0-2 0-3 0-5 ZrO.sub.2 0-7 1-4 2-5 0-2 0-4 0-5 As.sub.2O.sub.3 0-1 0-1 0-1 0-1 0-1 0-1 Sb.sub.2O.sub.3 0-15 0-1 0-1 0-1 0-15 0-1 F 0-3 0-1 0-1 0-1 0-1 0-1 H.sub.2O 0-5 0-3 0-3 0-3 0-3 0-3

(12) Other glasses according to the disclosure for producing glass flow forming particles, which are mainly used for producing haptic layers on glasses, in particular on soda-lime glasses, are summarized in Table 5:

(13) TABLE-US-00005 Wt. % Glass G Glass H Glass I Glass J Glass K SiO.sub.2 25-55 35-65 30-54 6-20 6-15 Al.sub.2O.sub.3 3-18 0 0-17.5 0-5 0 B.sub.2O.sub.3 5-25 0 13-28 20-38 20-28 Li.sub.2O 0-12 0-6 3-6 0 0 Na.sub.2O 3-18 0-6 4-10 0 0 K.sub.2O 3-18 0-6 0-2 0 0 CaO 3-17 0-12 0-6 0 0 MgO 0-10 0-12 0-4 0 0 BaO 0-12 0-38 0 0 0 SrO 0 0-16 0-4 0 0 ZnO 0 17.5-38.sup. 3-13 35-70 58-70 TiO.sub.2 0-5 0 0-2 0-5 0 ZrO.sub.2 0-3 0 0-2 0-5 0 Bi.sub.2O.sub.3 0 0 0 0-20 0 CoO 0 0 0 0-5 0 Fe.sub.20.sub.3 0 0 0 0-5 MnO 0 0 0 0-10 0.5-1.sup. Ce0.sub.2 0 0 0 0 0-3 F 0 0 .sup.0-3.3 0-6 0

(14) The glasses were melted and were ground when cooled down, to produce a glass flow forming particle.

(15) Then the glass flow forming particles were mixed with the texturing particles, to produce the glass frit according to the disclosure. By adding screen-printing oils, pastes were prepared, which were applied onto lithium aluminosilicate glass ceramic substrates by screen printing. Burning-in of the applied paste was accomplished during ceramization.

(16) FIG. 1 shows various possible embodiments of locally patterned haptic layers on a substrate 20. Without being limited to the specific embodiment of FIG. 1, the substrate may in particular comprise a glass or glass ceramic kitchen element, wherein the layer with texturing particles is a printing on the kitchen element. In particular, the layer is suitable for a local or full-area printing on a bulk colored and/or color-coated glass ceramic cooktop, for radiation heaters and/or induction cookers.

(17) In FIG. 1 the areas identified by 10 illustrate embodiments of slide switches which are designed with touch sensitivity. Sections 10 of the substrate surface with the touch-sensitive slide switches were produced with a layer that causes a velvety haptic perception.

(18) The sections of the substrate surface denoted by 11 illustrate two areas that have been provided with a layer that produces a rough haptic perception. These functional areas are formed as cooking hobs, the rough haptic perception being advantageous due to the better static friction thereof.

(19) FIG. 2 shows a layer 21 on a transparent substrate 20. Spherical texturing polymethylsiloxane particles did not or not significantly alter their outer contours during application and burning-in since they have a very high melting point above the burning-in temperature. Therefore, they may be present as particles 22 fully embedded in the layer, or as only partially embedded particles 24. Furthermore, a portion thereof may be covered by the layer, so that one surface portion of particle 23 is free of glass. Such a layer with a homogeneous distribution of the texturing particles in terms of the height and width of the spherical outer contour causes a velvety haptic perception.

(20) FIG. 3 illustrates a layer in which both texturing particles with a melting point above the burning-in temperature and texturing particles with a lower softening temperature were used, for example particles of alkali aluminosilicate glass or low-alkali borosilicate glass. For the texturing particles of the lower softening point, partial melting occurs during burning-in, so that fragments are formed. Portions of fragments 31 protrude from the layer as a point and cause a rough haptic perception.

(21) FIG. 4 shows a scanning electron micrograph of a layer with a velvety haptic perception, and FIG. 5 illustrates a layer with a rough haptic perception, in cross section.

Example 1

Preparation of a Layer with Velvety Haptics

(22) 19 g of glass flow forming particles of a ground glass C are mixed with 61.5 g of screen printing pasting medium and 19 g of texturing homogeneous spherical methylpolysiloxane particles with a mean particle size of 4.5 m. The so produced paste is homogenized for 10 min using a Dispermat.

(23) Then, textured layers are applied on green glass by screen printing using a 140 mesh screen. The so applied layers are dried at a temperature of 180 C. for 30 min. Burning-in is accomplished at 900 C. during the ceramization of a bulk colored glass ceramic substrate.

(24) In this way, haptic layers according to the disclosure are obtained with a velvety feel and good chemical and mechanical functional characteristics.

Example 2

Preparation of a Layer with Rough Haptics (Variation A)

(25) 17 g of glass flow forming particles of a ground glass C are mixed with 60 g of screen printing pasting medium and 14 g of texturing particles of a mixture of spheres and idiomorphous (edged) particles of alkali aluminosilicate glass, with 95% thereof having a particle size of not more than 12 m. This paste is homogenized for 10 min using a Dispermat. Then, textured layers are applied on green glass by screen printing using a 140 mesh screen. These layers are dried at 180 C. for 30 min.

(26) Burning-in is accomplished at about 900 C. during ceramization of the bulk colored glass ceramic.

(27) In this way, haptic layers according to the disclosure are obtained with rough haptics and good chemical and mechanical functional characteristics.

Example 3

Preparation of a Layer with Rough Haptics (Variation B)

(28) 17 g of glass flow forming particles of a ground glass C are mixed with 60 g of screen printing pasting medium and 14 g of texturing particles of a mixture of spheres and idiomorphous (edged) particles of low-alkali borosilicate glass, with 95% thereof having a particle size of not more than 24 m.

(29) This paste is homogenized for 10 min using a Dispermat. Then, textured layers are applied on green glass by screen printing using a 140 mesh screen. These layers are dried at 180 C. for 30 min.

(30) Burning-in is accomplished at about 900 C. during ceramization of the bulk colored glass ceramic.

(31) In this way, haptic layers according to the disclosure are obtained with rough haptics and good chemical and mechanical functional characteristics.

Example 4

Preparation of a Layer with Velvety Haptics and Anti-Fingerprint Effect and Matting Properties

(32) 19 g of glass flow particles of a ground glass frit of a glass flow composition (glass C) are mixed with 61.5 g of screen printing pasting medium and 19 g of texturing homogeneous spherical methylpolysiloxane particles with a mean particle size of 4.5 m.

(33) This paste is homogenized for 10 min using a Dispermat. Then, textured layers are applied on green glass by screen printing using a 140 mesh screen. These layers are dried at a temperature of 180 C. for 30 min.

(34) Burning-in is accomplished at about 900 C. during ceramization of the non-bulk colored glass ceramic.

(35) In this way, haptic layers according to the disclosure are obtained with velvety haptics, fingerprint unobtrusiveness and matting visual properties.

Example 5

Preparation of a Layer with Velvety Haptics and Anti-Fingerprint Effect and Matting Properties

(36) 19 g of glass flow particles of a ground glass frit (zinc borate flow, glass J) are mixed with 61.5 g of screen printing pasting medium and 19 g of texturing homogeneous spherical methylpolysiloxane particles with a mean particle size of 4.5 m.

(37) This paste is homogenized for 10 min using a Dispermat. Then, textured layers are applied on low-iron soda-lime glass of a thickness of 4 mm by screen printing using a 140 mesh screen. These layers are dried at 130 C. for 5 min. Burning-in is accomplished at about 710 C. for 3 min during the tempering process.

(38) In this way, haptic layers according to the disclosure are obtained with a velvety feel, fingerprint unobtrusiveness and matting visual properties.

Example 6

Preparation of a Layer with Velvety Haptics and Anti-Fingerprint Effect and Matting Properties

(39) 70 g of a 60 mass % solution of a high-temperature stable phenyl methylpolysiloxane resin in xylene (trade name REN80, Wacker Silicones) are mixed with 19 g of texturing homogeneous spherical methylpolysiloxane particles with a mean particle size of 4.5 m.

(40) This screen printing paste is homogenized for 10 min using a Dispermat.

(41) Then, textured layers are applied on toughened low-iron soda-lime glass of a thickness of 4 mm by screen printing using a 140 mesh screen. These layers are cured at 300 C. for 1 h.

(42) In this way, haptic layers according to the disclosure are obtained with a velvety feel, fingerprint unobtrusiveness and matting visual properties.

Example 7

Preparation of a Layer with a Velvety Feel and Anti-Fingerprint Effect and Matting Properties

(43) 40 g of a solvent-free two-component epoxy-functionalized polysiloxane resin (Silikophon EC, by Evonic) are mixed with 19 g of texturing homogeneous spherical methylpolysiloxane particles with a mean particle size of 4.5 m.

(44) This screen printing paste is homogenized for 10 min using a Dispermat.

(45) Then, textured layers are applied on toughened low-iron soda-lime glass of a thickness of 4 mm by screen printing using a 140 mesh screen. These layers are cured at 200 C. for 60 min.

(46) In this way, haptic layers according to the disclosure are obtained with a velvety feel, fingerprint unobtrusiveness and matting visual properties.

(47) A comparison of the properties of two coated substrates according to the disclosure with reference samples will now be discussed below. Transparent glass ceramics has been used as a substrate for the inventive article. For a first sample, the glass ceramic was coated with a layer having a rough haptic appearance, and for a second sample with a layer having a velvety haptic appearance. The samples were compared with etched glass, with non-etched flat soda-lime glass (referred to as SL glass below), and with a transparent, uncoated glass ceramic. The following table shows a comparison of several visual and mechanical properties:

(48) TABLE-US-00006 Sample 1: Sample 2: Transparent Transparent Transparent Glass Glass Etched SL Glass Ceramic, Ceramic, Glass Glass Ceramic Rough Velvety Trans- 81.6 91.7 90.9 82.4 79.6 mittance [%] Haze [%] 95.1 0.3 0.2 71.8 84.6 Gloss [%] 6.6 99.9 99.7 21.2 25.9 Static 0.69 0.79 0.94 0.82 Friction PV [m] 19.707 0.058 0.619 8.329 8.115 RMS [m] 4.807 0.002 0.089 0.598 1.180 Ra [m] 4.133 0.002 0.070 0.444 1.035

(49) As can be seen from the table and from FIG. 6, the transmittance of coated samples 1 and 2 according to the disclosure is similar to that of an etched glass. Due to the light scattering resulting at the rough surface, the transmittance is lower than that of an uncoated transparent glass ceramic and of soda-lime glass.

(50) However, the haze value and gloss of the samples according to the disclosure differ significantly from the values of an etched glass. The haze value is lower than that of etched glass, whereas the gloss value is higher. The haze value represents the portion of the reflected light that is deflected in a small solid angle range around the mirrored beam. The gloss value, by contrast, represents the portion of the light reflected along the mirrored beam. These properties result in a different visual appearance as compared to etched glass. While the latter has a rather dull appearance, the lower haze and higher gloss values of the inventive samples result in a more silky appearance.

(51) Generally, according to one embodiment of the disclosure and supported by the exemplary values in the table, the layers can be distinguished in terms of their visual properties, by a haze value of the light reflected at the layer ranging from 65% to 90%, and/or by a gloss value ranging from 15% to 35%.

(52) As can be seen from FIG. 7, the curves of scattering in function of the scattering angle for samples 1, 2 and the etched glass do not differ clearly in a wide range of angles, so that the visual appearance of substrates according to the disclosure under diffusely scattered light is quite similar to that of an etched glass. However, there are significant differences at small scattering angles. The curve of the etched glass has a plateau in the range of about 15. For samples 1 and 2 according to the disclosure, by contrast, the light intensity continues to significantly increase as the scattering angle decreasing, and in this regard it is similar to the scattering curve of an uncoated glass ceramic. It should also be noted here, that the intensity scale in FIG. 7 is logarithmic.

(53) This property is advantageous, when illuminating display elements such as LED operation displays are arranged below a coated area of a substrate according to the disclosure. Both legibility and sharpness of the display are substantially preserved through the layer. In contrast, the light transmitted through an etched glass, is evenly scattered in a range of 10, so that the visibility of the contours of a display is at least severely restricted.

(54) Therefore, according to one modification of the disclosure, without being limited to the exemplary embodiments, a device is provided which comprises a coated substrate according to the disclosure, and an illuminating display is provided on one surface of the substrate, and at least the surface area of the substrate opposite to and facing away from the display, is provided with a layer having haptic properties. In particular, this may again be a glass ceramic cooktop comprising a transparent glass ceramic panel which has an upper surface coated with the layer according to the disclosure, and wherein a display element is arranged below or at the lower surface of the glass ceramic panel, so that the display element when in operation shines through the layer on the upper surface.

(55) According to yet another embodiment of the disclosure, the property of the layer to deflect a greater proportion of light intensity transmitted through the substrate to small scattering angles, as compared to etched glass, may be quantified as follows: The ratio of the intensity of light, which is transmitted through the substrate and the layer and passes at an angle of 0 (i.e. of the non-scattered light), to the intensity of light which is transmitted through the substrate and the layer and is scattered in an angle of 10, is at least 2, preferably at least 5. For comparison, and as can be seen in FIG. 7, this ratio is approximately 1 for the etched sample. That means, in this case the intensity of the light scattered at 10 is almost the same as that of the light transmitted at 0.

(56) Finally, FIGS. 8 and 9 show light micrographs of the samples of substrates coated according to the disclosure. FIG. 8 shows an image of the coated surface of sample 1, and FIG. 9 is an image of the coated surface of sample 2. FIG. 10 shows a micrograph of the etched surface of the etched glass, for purposes of comparison. In the light micrographs, the etched glass sample in FIG. 10 appears to be the roughest. Surprisingly, however, both samples according to the disclosure exhibit a higher static friction, as is apparent from the table above. According to yet another embodiment, without limitation to the exemplary embodiments shown in the figures, substrates coated according to the disclosure may further be characterized by their coefficient of static friction, which is at least 0.8. The RMS and Ra values of the layers are substantially smaller than those of an etched glass. For both samples, these values amount to not more than a quarter of the corresponding values of an etched glass. According to yet another modification of the disclosure, without limitation to the exemplary embodiments, the layers according to the disclosure may be characterized by an RMS value and/or an Ra value of not more than 2 m.