COMPOSITE PANE COMPRISING A SUN SHADING COATING

Abstract

A composite pane includes an outer pane having an exterior-side surface and an interior-side surface, an inner pane having an exterior-side surface and an interior-side surface, and a thermoplastic intermediate layer joining the interior-side surface of the outer pane to the exterior-side surface of the inner pane. The composite pane has a sun shading coating between the outer and inner panes. the sun shading coating includes, starting from the outer pane toward the inner pane, a layer sequence first dielectric module M1, first silver layer Ag1, second dielectric module M2, second silver layer Ag2, third dielectric module M3, third silver layer Ag3, fourth dielectric module M4, wherein the silver layers have, relative to one another, a geometrical layer thickness of 0.4<Ag1/Ag3<1.7, and Ag3 or Ag2 is the thickest silver layer, and wherein the dielectric modules have, relative to one another, an optical layer thickness of M2/M1≥1.9, M2/M3≥0.8, and M2/M4≥1.6.

Claims

1. A composite pane, comprising an outer pane having an exterior-side surface and an interior-side surface, an inner pane having an exterior-side surface and an interior-side surface, and a thermoplastic intermediate layer, which joins the interior-side surface of the outer pane to the exterior-side surface of the inner pane, wherein the composite pane has at least one sun shading coating between the outer pane and the inner pane, wherein the sun shading coating comprises, starting from the outer pane toward the inner pane, a layer sequence first dielectric module, first silver layer, second dielectric module, second silver layer, third dielectric module, third silver layer, fourth dielectric module, wherein the first, second and third silver layers have, relative to one another, a geometrical layer thickness of 0.4<Ag1/Ag3<1.7; and Ag3 or Ag2 is the thickest silver layer, where Ag1 is the geometrical layer thickness of the first silver layer, Ag2 is the geometrical layer thickness of the second silver layer, and Ag3 is the geometrical layer thickness of the third silver layer; and wherein the first, second, third and fourth dielectric modules have, relative to one another, an optical layer thickness of M2/M1≥1.9, M2/M3≥0.8, and M2/M4≥1.6, where M1 is the optical layer thickness of the first dielectric module, M2 is the optical layer thickness of the second dielectric module, M3 is the optical layer thickness of the third dielectric module and M4 is the optical layer thickness of the fourth dielectric module and wherein all dielectric layers of the first, second, third and fourth dielectric modules have a refractive index greater than 1.8.

2. The composite pane according to claim 1, wherein the first, second and third silver layers of the sun shading coating have, relative to one another, a geometrical layer thickness of 0.6<Ag1/Ag3<1.7; Ag2 is the thickest silver layer; and the first, second, third and fourth dielectric modules have, relative to one another, an optical layer thickness of M2/M1≥2, M2/M3>1, and M2/M4≥2.

3. The composite pane according to claim 1, wherein the first, second and third silver layers of the sun shading coating have, relative to one another, a geometrical layer thickness of 0.4<Ag1/Ag3<0.9, and 0.5<Ag2/Ag3<1.0; Ag3 is the thickest silver layer; and the first, second, third and fourth dielectric modules have, relative to one another, an optical layer thickness of M2/M1≥1.9, M2/M3≥0.8, and M2/M4≥1.6.

4. The composite pane according to claim 1, wherein the first dielectric module, the second dielectric module, the third dielectric module, and/or the fourth dielectric module have at least one dielectric layer based on silicon nitride.

5. The composite pane according to claim 1, wherein the first dielectric module, the second dielectric module, the third dielectric module, and/or the fourth dielectric module include at least one first dielectric layer based on silicon nitride and at least one second dielectric layer based on zinc oxide.

6. The composite pane according to claim 1, wherein the first dielectric module the second dielectric module, the third dielectric module, and/or the fourth dielectric module include at least one first dielectric layer based on silicon nitride, at least one second dielectric layer based on zinc oxide, and at least one third dielectric layer based on a mixed tin-zinc oxide.

7. The composite pane according to claim 1, wherein the sun shading coating includes, above and/or below the first, second and third silver layers, in each case, at least one metallic blocking layer, which has a geometrical thickness of less than 1 nm.

8. The composite pane according to claim 1, wherein the first silver layer, the second silver layer, and the third silver layer have, in each case, a geometrical thickness of 5 nm to 25 nm.

9. The composite pane according to claim 1, wherein the first dielectric module, the second dielectric module, the third dielectric module, and the fourth dielectric module have, in each case, a geometrical thickness of 10 nm to 100 nm.

10. The composite pane according to claim 1, wherein the sun shading coating is applied on the interior-side surface of the outer pane.

11. The composite pane according to claim 1, wherein a thermal-radiation-reflecting coating is applied on the interior-side surface of the inner pane.

12. The composite pane according to claim 11, wherein the thermal-radiation-reflecting layer has a functional layer based on an indium-tin oxide layer or a tin oxide layer, wherein the indium-tin oxide layer or the tin oxide layer is arranged between two dielectric layers.

13. Method A method for producing a composite pane according to claim 1 comprising: a) applying a sun shading coating to the inner surface of the outer pane, or to the outer surface of the inner pane, or introducing the sun shading coating into a thermoplastic intermediate layer, b) producing a layer stack comprising at least, in this order, the outer pane, the thermoplastic intermediate layer, and the inner pane, and c) joining the layer stack comprising at least the outer pane, the thermoplastic intermediate layer, and the inner pane to form the composite pane.

14. The method for producing a composite pane according to claim 13, wherein a thermal-radiation-reflecting coating is applied to the inner surface of the inner pane.

15. A method comprising providing a composite pane according to claim 1 in a motor vehicle as a windshield, rear window, side window, and/or roof panel.

16. The composite pane according to claim 8, wherein the first silver layer, the second silver layer, and the third silver layer have, in each case, a geometrical thickness of 8 nm to 20 nm.

17. The composite pane according to claim 9, wherein the first dielectric module, the second dielectric module, the third dielectric module, and the fourth dielectric module have, in each case, a geometrical thickness of 20 nm to 90 nm.

18. The composite pane according to claim 17, wherein the first dielectric module, the second dielectric module, the third dielectric module, and the fourth dielectric module have, in each case, a geometrical thickness of 70 nm to 85 nm.

19. The method according to claim 15, wherein the composite pane is a roof panel of a motor vehicle.

Description

[0097] The drawings are simplified schematic representations and are not to scale. The drawings in no way restrict the invention.

[0098] They depict:

[0099] FIG. 1 a cross-section through a first embodiment of the composite pane according to the invention having a sun shading layer and a thermal-radiation-reflecting layer,

[0100] FIG. 2 a cross-section through another embodiment of the composite pane according to the invention having a sun shading layer and a thermal-radiation-reflecting layer,

[0101] FIG. 3 a cross-section through another embodiment of the composite pane according to the invention having a sun shading layer and a thermal-radiation-reflecting layer,

[0102] FIG. 4 a schematic representation of the structure of a sun shading layer according to the invention applied on the outer pane of the composite pane, and

[0103] FIG. 5 a flow chart of an embodiment of the method according to the invention.

[0104] FIG. 1 depicts a cross-section through an embodiment of the composite pane 100 according to the invention having a sun shading coating 4 and a low-E coating 5. The composite pane 100 comprises an outer pane 1 and an inner pane 2 joined to one another via a thermoplastic intermediate layer 3. The composite pane 100 can, for example, be provided as a roof panel of a passenger car, with the outer pane 1 facing the external surroundings and the inner pane 2 facing the vehicle interior. The outer pane 1 has an outer surface (1) and an inner surface (II). The inner pane 2 has an outer surface (III) and an inner surface (IV). The outer surfaces (1) and (III) face the external surroundings; the inner surfaces (II) and (IV) face the vehicle interior. The inner surface (II) of the outer pane 1 and the outer surface (III) of the inner pane 2 face one another. In this embodiment, a sun shading coating 4 according to the invention is arranged on the inner surface (II) of the outer pane 1. The sun shading coating 4 extends over the entire inner surface (II), preferably minus a circumferential frame-shaped coating-free region, for example, with a width of 8 mm. The coating-free region can then be hermetically sealed by bonding to the thermoplastic intermediate layer 3. The sun shading coating 4 is thus advantageously protected against damage and corrosion. According to the invention, the sun shading coating 4 comprises at least three functional silver layers, each of which has a layer thickness between 5 nm and 20 nm, with each functional silver layer being arranged between dielectric modules, for example, layers of silicon nitride. The silver layers (Ag1, Ag2, Ag3) of the sun shading coating according to the invention have a geometrical layer thickness relative to one another of 0.4<Ag1/Ag3<1.7, with Ag2 or Ag3 being the thickest silver layer, and the dielectric modules (M1, M2, M3, M4) have an optical layer thickness relative to one another of M2/M1≥1.9, M2/M3≥0.8, and M2/M4≥1.6. The structure of the sun shading coating 4 according to the invention is described in more detail below with FIG. 4 and the examples and comparative examples explained there. The sun shading coating 4 results in reduced heating of the vehicle interior and of the inner pane 2 due to the reflection of infrared radiation. According to the invention, energy reflection RE>36%, preferably >39% can be achieved. Also, in addition to good improved thermal comfort compared to previously known systems, with the sun shading coating 4 according to the invention, good optical and aesthetic properties of the composite pane 100 are achieved at the same time. A thermal protection coating 5 is optionally arranged on the inner surface (IV) of the inner pane 2. In this preferred embodiment, it is possible for the composite pane to have not only good energy reflection RE>40%, but also particularly low total transmitted thermal radiation of TTS<14%. On the one hand, the thermal protection coating 5 reduces the emission of thermal radiation through the composite pane 100 into the vehicle interior, in particular when outside temperatures are high. On the other hand, the thermal protection coating 5 can reduce the emission of thermal radiation out of the vehicle interior when outside temperatures are low, in addition, the thermal protection coating 5 can reduce the transmittance of visible light into the vehicle interior. These are major advantages of the composite pane according to the invention, since the interior climate of the vehicle is significantly improved and the need for the use of air conditioning systems is reduced. In terms of the energy properties, in particular to achieve energy reflection RE>36 and the lowest possible TTS value of the resulting composite pane 100, it is preferred according to the invention to apply the sun shading coating 4 on a clear, non-tinted glass pane (inner side II of the outer pane 1). On the other hand, optionally, in order to neutralize, or improve, the external appearance of the composite pane 100, it can be useful for the sun shading coating 4 to be applied on a tinted glass pane (outer pane 1). Such a configuration of the composite pane according to the invention with a clear untinted outer pane, a tinted thermoplastic intermediate layer, and a tinted inner pane is, in particular, suitable as a roof panel of a vehicle.

[0105] FIG. 2 depicts a cross-section through another embodiment of the composite pane 100 according to the invention having a sun shading coating and a thermal protection coating 4, 5. In contrast to FIG. 1, the sun shading coating 4 is arranged not on the inner surface (II) of the outer pane 1, but on a carrier film 6 in the intermediate layer 3. The sun shading coating 4 can optionally be arranged on the surface of the carrier film facing the inner pane 2 or the outer pane 1, with, in each case, the thickness ratios of the layers according to the invention being complied with. The carrier film 6 preferably contains or is made of polyethylene terephthalate (PET) and has, for example, a thickness of 50 μm. The sun shading layer 4 according to the invention comprises a layer structure, which is explained in greater detail with regard to FIG. 4. The carrier film 6 with the sun shading coating 4 is arranged between a first thermoplastic film 3a and a second thermoplastic film 3b. In the resulting composite pane, the thermoplastic films 3a and 3b and the carrier film 6 form the thermoplastic intermediate layer 3. The thermoplastic films 3a and 3b preferably contain or are made of PVB and have, for example, a layer thickness of 0.38 mm. The carrier film 6 is somewhat smaller than the outer pane 1, the inner pane 2, and the thermoplastic films 3a and 3b. The carrier film 6 is arranged in the composite such that the carrier film 6 does not extend all the way to the lateral edges of the composite glass. As a result, the carrier film 6 is surrounded in the edge region of the composite pane for example, circumferentially by the thermoplastic films 3a and 3b, with a width of approx. 8 mm. The sun shading coating 4 on the carrier film 6 is thus advantageously protected against damage and, in particular, corrosion. The thermal protection coating 5 on the inner surface (IV) of the inner pane 2 is designed as in FIG. 1.

[0106] FIG. 3 depicts a cross-section through another embodiment of the composite pane 100 according to the invention having a sun shading coating and a thermal protection coating 5, 4. In contrast to FIG. 1, the sun shading coating 4 is arranged not on the inner surface (II) of the outer pane 1, but on the outer surface (III) of the inner pane 2, with a circumferential edge region of the outer surface (III) not provided with the sun shading coating 4. In this embodiment as well, the sun shading coating 4 is advantageously protected against damage and corrosion. For the rest, this embodiment corresponds to the design depicted in FIG. 1.

[0107] FIG. 4 depicts a schematic structure of a sun shading layer 4 according to the invention. In the embodiment depicted, the sun shading coating 4 is applied on the inner side II of the outer pane 1 as a substrate. The sun shading coating 4 depicted contains three transparent functional silver layers Ag1, Ag2, and Ag3, which are, in particular, the infrared radiation-reflecting layers. According to the invention, these functional silver layers have a certain thickness relative to one another; specifically, provision is made according to the invention for the relative geometrical layer thicknesses to have 0.4<Ag1/Ag3<1.7 and Ag3 or Ag2 to be the thickest silver layer. In other words, the layer thickness of the first silver layer Ag1, which is arranged closest to the outer pane 1, is thinner than the second silver layer Ag2 or the third silver layer Ag3 following above in the layer sequence. The silver layers can be deposited, for example, by cathodic sputtering in an argon atmosphere.

[0108] Dielectric modules M1, M2, M3, and M4 including dielectric layers are in each case arranged above, below, and between the silver layers Ag1, Ag2, and Ag3. According to the invention, these dielectric modules (M1, M2, M3, M4) have, relative to one another, an optical layer thickness M2/M1≥1.9, M2/M3≥0.8, and M2/M4≥1.6. The dielectric module M1 is thus arranged below the first silver layer Ag1 directly on the inner side II of the outer pane 1; the second dielectric module M2 is arranged above the first silver layer Ag1. The first dielectric module M1 can, for example, be structured, starting from the outer pane 1, as a layer sequence of silicon nitride, ZnSnOx, and ZnO layers. The silicon nitride layer can be deposited from silicon nitride in a nitrogen-containing atmosphere; the zinc oxide layer, from zinc oxide in an oxygen-containing atmosphere.

[0109] The sun shading coating 4 contains at least one blocking layer; particularly preferably each functional silver layer Ag1, Ag2, Ag3 is situated, as depicted, in direct contact with at least one blocking layer B1, B2, and B3. According to the invention, the blocking layers preferably contain or are made of at least nickel, chromium, or alloys thereof and/or titanium chromium. The blocking layers B (B1, B2, B3) are preferably arranged between at least one functional silver layer and at least one dielectric layer. The blocking layers B protect the functional layer during heating, in particular during production of the composite pane according to the invention.

[0110] The invention is explained with reference to the following Examples according to the invention and Comparative Examples not according to the invention.

Examples

[0111] All optical, aesthetic, and energy properties of the composite panes according to the Examples and the Comparative Examples were measured in the laminated state. In the Examples and Comparative Examples, the sun shading coating 4 was applied to the inner side II of a clear outer pane 1 (Example Planiclear) in accordance with FIG. 4 and laminated with a thermoplastic intermediate layer 3 and an inner pane 2 in accordance with the structure of FIG. 1. A tinted PVB film was used in the intermediate layer. The low-E coating was applied to the inner side IV of a darkly tinted inner pane 2 (Example VG10). The low-E coating had emissivity of 30%. The low-E coating is based on an ITO (indium-tin oxide) layer that is encapsulated between dielectric layers (Si.sub.3N.sub.4, SiO.sub.x). The Examples and Comparative Examples have the same basic structure described, but differ in the sun shading coatings used.

[0112] Examples 1 through 10 according to the invention and Comparative Examples not according to the invention were produced as a composite pane (windshield for a vehicle) with the sun shading coatings indicated.

[0113] For each Example and Comparative Example, the stack structure of the sun shading coating (layers and layer thicknesses) and the optical properties of the coating in the finished composite pane are indicated.

[0114] The layer sequences and layer thicknesses of the sun shading coatings in accordance with Examples 1 to 10 according to the invention are presented in Table 1a. In comparison, the Comparative Examples 1 to 4 not according to the invention are described in Table 1b. The relative layer thicknesses of the silver layers and of the dielectric modules, as well as the values of the optical and energy properties are reported for the Examples 1 to 10 according to the invention in Table 2a; and for the Comparative Examples 1 to 4 not according to the invention, in Table 2b. All layer thicknesses of the silver layers and of the layers of the modules are indicated as geometrical layer thicknesses. The relative layer thicknesses of the silver layers, indicated as thickness ratios Ag2/Ag1, Ag2/Ag3, and Ag1/Ag3 refer to the geometrical layer thicknesses. For the relative layer thicknesses of the dielectric modules, indicated as thickness ratios M2/M1, M2/M3, and M2/M4, the optical thicknesses were used.

Abbreviations

[0115] RE energy reflection [%] [0116] TL visible light transmittance [%] [0117] TTS total transmitted thermal radiation [%] [0118] TE total transmitted energy [%] [0119] RL 8° visible reflection at a viewing angle of 8° [%] [0120] a*, b* color coordinates in the CIE color space (International Commission on Illumination), measured in each case in reflection at an angle of 60° and at an angle of 8° [0121] Δa*, Δb* difference in the color coordinates when measured in reflection at 60° and at 8° [0122] Color R* color impression of the external reflection color in each case in reflection at 60° and at 8° perceived by the viewer of the composite pane

[0123] The values for light transmittance (TL) and reflection (RL) are based on illuminant A, i.e., the visible portion of sunlight at a wavelength of 380 nm to 780 nm.

TABLE-US-00001 TABLE 1a Examples 1-10 Layer Structures of the Sun Shading Coating Layer sequence Layer Outer material Layer Thicknesses [nm] per Example According to the Invention pane 1 Glass #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 M1 SiZrN.sub.x 16.1 15.7 15.7 16.4 8 9.8 7.3 10.6 9.8 10.8 ZnSnO.sub.x 8 8 8 8 8 8 7.5 7.5 7.5 7.7 ZnO 10 10 10 10 10 10 10.8 11 11 11.3 Ag1 Ag 8.5 9.3 10 9.4 8 10.6 11.6 11.8 10.4 11.9 B1 NiCr 0.2 0.2 0.2 0.2 0.2 0.2 0.6 0.6 0.3 0.1 M2 ZnO 10 10 10 10 10 10 12.2 15 15 13.3 SiZrN.sub.x 10 10 10 10 10 20.3 16.6 16 15.5 16.7 Si.sub.3N.sub.4 21.8 22.3 22.3 22.8 13.2 15 22.2 12.4 6.5 14.7 SiZrN.sub.x 10 10 10 10 10 15 6.2 10.9 16.5 17.1 ZnSnO.sub.x 8 8 8 8 8 8 7.5 9.3 9.3 8.7 ZnO 10 10 10 10 10 10 12.2 14 14 12.4 Ag2 Ag 10.5 11.4 12 11.8 10.2 12 12.6 14.2 15 14.4 B2 NiCr 0.2 0.2 0.2 0.2 0.2 0.2 0.8 0.8 0.3 0.1 M3 ZnO 10 10 10 10 10 10 10.8 13 13 12.8 Si.sub.3N.sub.4 15 15 15 15 15 15 24.4 5.4 10.5 14.9 SiZrN.sub.x 31.1 31.3 31.3 33.1 28 20.9 9.9 13.8 16.6 17.5 ZnSnO.sub.x 8 8 8 8 8 8 7.5 9.0 9 7.1 ZnO 10 10 10 10 10 10 10.8 13 13 12.9 Ag3 Ag 13.3 13.9 14 17.6 15.7 10.3 10.6 9.7 9.9 10.4 B3 NiCr 0.2 0.2 0.2 0.2 0.2 0.2 1.5 0.5 1.3 0.1 M4 ZnO 10 10 10 10 10 10 12.2 15 15 15.5 Si.sub.3N.sub.4 14.7 15.2 15.2 17 10.2 25.4 15.3 3.1 19.5 20.6

TABLE-US-00002 TABLE 1b Comparative Examples 1-4 Layer Structures of the Sun Shading Coating Layer Thicknesses [nm] per Layer Layer Comparative Example sequence material #1 #2 #3 #4 Outer pane 1 Glass M1 SiZrN.sub.x 22 16.4 9.8 9.8 ZnSnO.sub.x 8 8 8 8 ZnO 11 10 10 10 Ag1 Ag 8.5 15 10.6 12.9 B1 NiCr 0.2 0.2 0.2 0.2 M2 ZnO 11 10 10 10 SiZrN.sub.x 10 10 8 14.7 Si.sub.3N.sub.4 21.8 21.8 8 15 SiZrN.sub.x 10 10 8 15 ZnSnO.sub.x 8 8 8 8 ZnO 11 10 10 10 Ag2 Ag 10.5 12 12.5 10.6 B2 NiCr 0.2 0.2 0.2 0.2 M3 ZnO 11 11 10 10 Si.sub.3N.sub.4 15 15 15 15 SiZrN.sub.x 31.1 22 30.6 19 ZnSnO.sub.x 8 8 8 8 ZnO 11 10 10 10 Ag3 Ag 13.3 10.5 11.7 8.9 B3 NiCr 0.2 0.2 0.2 0.2 M4 ZnO 11 10 10 10 Si.sub.3N.sub.4 14.7 14.7 25.4 25

TABLE-US-00003 TABLE 2a Examples 1-10 Thickness Ratios and Optical Properties in the Laminate Thickness Ratios and Optical Properties per Example #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 Thickness Ratios Ag2/Ag1 1.23 1.23 1.20 1.25 1.27 1.10 1.10 1.20 1.40 1.20 Ag2/Ag3 0.79 0.82 0.86 0.67 0.65 1.20 1.20 1.50 1.50 1.40 Ag1/Ag3 0.64 0.67 0.71 0.53 0.51 1.00 1.10 1.20 1.10 1.10 M2/M1 1.99 2.02 2.03 2.00 2.35 2.80 3.0 2.70 2.70 2.80 M2/M3 0.92 0.92 0.93 0.91 0.85 1.20 1.20 1.40 1.30 1.3 M2/M4 2.95 2.92 2.92 2.74 3.19 2.40 2.90 4.50 2.40 3.60 Optical Properties TL 6.2 6.2 6.1 5.5 5.6 6.3 5.2 5.2 5.40 6.2 RL 8° 11.7 12.1 12.0 18.9 17.4 11.9 10.7 12.9 14.0 13.8 a*R 8° −4.1 −3.7 −5.3 −4.4 −4.6 −4.4 −4.6 −1.6 −5.6 −5.2 b*R 8° −10.8 −11.5 −11.3 −10.6 −6.6 −10.8 −10.3 −10.5 −8.9 −8.5 a*R 60° −3.4 −3.8 −4.1 −2.7 −3.0 −4.5 −5.1 −2.8 −2.0 −3.3 b*R 60° −7.5 −6.6 −6.0 −8.4 −2.7 −7.2 −7.5 −6.2 −8.4 −8.3 Color R*8° blue blue blue blue blue blue blue blue blue blue (Color R*60° blue blue blue blue neutral blue blue blue blue blue Δ a*R (8° vs. 60°) 0.7 −0.1 1.2 1.7 1.6 −0.1 −0.5 −1.2 3.6 1.9 Δ b*R (8° vs. 60°) 3.3 4.9 5.3 2.2 4.0 3.6 2.8 4.3 0.4 0.2 RE 44.0 44.8 47.6 51.0 49.2 45.2 41.7 44.4 44.1 46.7 TE 3.0 2.8 2.7 2.4 2.4 3.0 2.7 2.6 2.8 3.2 TTS 13.6 13.3 12.6 11.7 12.1 13.4 13.8 13.2 13.4 13.4

TABLE-US-00004 TABLE 2b Comparative Examples 1-4 Thickness Ratios and Optical Properties in the Laminate Thickness Ratios and Optical Properties per Comparative Example #1 #2 #3 #4 Thickness Ratios Ag2/Ag1 1.2 0.8 1.2 0.8 Ag2/Ag3 0.8 1.1 1.1 1.2 Ag1/Ag3 0.6 1.4 0.9 1.4 M2/M1 1.7 2.0 1.9 2.6 M2/M3 0.9 1.1 0.7 1.2 M2/M4 2.9 3.0 1.5 2.2 Optical Properties TL 6.1 6.1 5.7 6.5 RL 8° 13.3 11.1 18.9 9.2 a*R 8° −14.1 2.2 −0.6 −4.3 b*R 8° 2.3 7.2 0.3 −14.1 a*R 60° −13.0 −3.0 9.7 2.3 b*R 60° −2.9 9.7 0.6 −8.2 Color R*8° yellow- orange neutral blue green Color R*60° green yellow rot violet Δ a*R 1.1 −5.2 10.3 7.1 (8° vs. 60°) Δ b*R −5.2 2.5 0.3 6.2 (8° vs. 60°) RE 38.8 44.8 52.4 46.2 TE 3.6 3.1 2.4 3.0 TTS 15.3 13.6 12.7 13.2

[0124] According to the invention, composite panes having a sun shading coating structured according to the invention are provided which were successfully improved in terms of energy properties, thermal and visual comfort, and at the same time in terms of aesthetic appearance, and were further optimized compared to known composite panes having sun shading coatings. Energy reflection of RE>41%, preferably of RE>39%, was achieved. With the sun shading coating according to the invention, composite panes can be provided in conjunction with a thermal-radiation-reflecting coating, which panes can additionally have a particularly low total transmitted thermal radiation (TTS) of less than 14%, while, at the same time, achieving optimum aesthetic appearance without undesirable color tones in the reflection of the composite pane. In particular, undesirable red and yellow reflections or hazing of the composite pane can be avoided. According to the invention, a substantially constant, desirable color reflection of the composite pane can be achieved regardless of the viewing angle.

[0125] Examples 1 to 5 according to the invention have silver layers Ag1, Ag2, and Ag3 with a relative geometrical layer thickness of 0.4<Ag1/Ag3<0.9 and 0.5<Ag2/Ag3<1.0, with Ag3 being the thickest silver layer and the dielectric modules (M1, M2, M3, M4) having an optical layer thickness of M2/M1≥1.9, M2/M3≥0.8, and M2/M4≥1.6 relative to one another. The Examples 1 to 5 have improved energy reflection.

[0126] For Examples 6 to 10 according to the invention, for the silver layers Ag1, Ag2, and Ag3, the relative geometrical layer thickness is 0.6<Ag1/Ag3<1.7, with Ag2 the thickest silver layer and the dielectric modules (M1, M2, M3, M4) having a relative optical layer thickness of M2/M1≥2, M2/M3>1, and M2/M4≥2. These composite panes are in particular advantageous in terms of the lowest possible angle-dependent color deviations Δ a in reflection.

[0127] FIG. 5 depicts an exemplary embodiment of the method according to the invention referencing a flow chart comprising the following steps. [0128] I Providing an outer pane 1, an inner pane 2, and at least one thermoplastic film to form the thermoplastic intermediate layer 3; [0129] II Applying a sun shading coating 4 according to the invention to the inner surface II of the outer pane 1 or to the outer surface III of the inner pane 2, for example, by means of cathodic sputtering; [0130] III Optionally applying a thermal protection coating 5 to the inner side IV of the inner pane 2; [0131] IV Joining the inner surface II of the outer pane 1 and the outer surface III of the inner pane 2 via the thermoplastic intermediate layer 3 to form a composite pane 100.

[0132] In one embodiment, glass panes are used as the outer pane 1 and as the inner pane 2. In a preferred embodiment of the method, the sun shading coating 4 having the at least three functional silver layers Ag1, Ag 2, and Ag3 and the at least four dielectric modules M1, M2, M3, and M4 is applied on the inner side II of the outer pane 1, preferably by means of magnetron-enhanced cathodic sputtering. Temporally, the sun shading coating 4 can be applied before, after, or simultaneously with the optional application of the thermal-radiation-reflecting coating 5 on the inner side IV of the inner pane 2. The joining of the outer pane 1 and the inner pane 2 via the intermediate layer 3 to form the composite glass is preferably done after both the sun shading coating 4 and the optional thermal protection coating 5 have been applied.

LIST OF REFERENCE CHARACTERS

[0133] 1 outer pane [0134] 2 inner pane [0135] 3 thermoplastic intermediate layer [0136] 3a first thermoplastic film [0137] 3b second thermoplastic film [0138] 4 sun shading coating [0139] 5 thermal protection coating [0140] 6 carrier film [0141] I outer surface of 1 [0142] II inner surface of 1 [0143] III outer surface of 2 [0144] IV inner surface of 2 [0145] Ag1 first silver layer [0146] Ag2 second silver layer [0147] Ag3 third silver layer [0148] M1 first dielectric module [0149] M2 second dielectric module [0150] M3 third dielectric module [0151] M4 fourth dielectric module [0152] B blocking layer [0153] B1 first blocking layer [0154] B2 second blocking layer [0155] B3 third blocking layer