Material comprising an absorbent layered element
A layered element with a discontinuous silver layer and carbon-enhanced dielectric matrix in glazing technologies addresses the challenge of achieving high selectivity and color neutrality by selectively absorbing green light, enhancing solar protection without reducing light transmission.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- SAINT GOBAIN VITRAGE SA
- Filing Date
- 2024-12-23
- Publication Date
- 2026-06-26
AI Technical Summary
Existing glazing technologies struggle to achieve high selectivity in solar radiation filtering while maintaining color neutrality, particularly in reducing green tint without significantly impacting light transmission.
A layered element comprising a discontinuous silver layer with nanometric silver particles encapsulated in a dielectric matrix, enhanced by a carbon layer, which selectively absorbs in the green range (490-550 nm) to neutralize red light absorption without affecting light transmission.
The solution achieves improved color neutrality and selectivity by minimizing the green tint effect, maintaining high light transmission and reducing solar factor without compromising on aesthetics.
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Abstract
Description
Title of the invention: Material comprising an absorbent layered element
[0001] The invention relates to a material comprising a transparent substrate coated with a layered element having particular absorption properties. The invention also relates to a material comprising a transparent substrate coated with a functional coating capable of acting on solar radiation and / or infrared (IR) radiation, the functional coating comprising this absorbing element. The invention further relates to glazing comprising these materials as well as the use of such materials for manufacturing thermal insulation and / or solar protection glazing.
[0002] In the following description, the term "functional" qualifying "functional coating" means "capable of acting on solar radiation and / or infrared (IR) radiation".
[0003] Glazing can be intended to equip both buildings and vehicles, in particular to prevent excessive overheating, so-called "solar control" glazing and / or to reduce the effort of air conditioning.
[0004] The selectivity “S” allows for the evaluation of the performance of these glazings. It corresponds to the ratio of the visible light transmission TLvis of the glazing to the solar factor FS of the glazing (S = TLvis / FS). The solar factor “FS or g” corresponds to the ratio, expressed as a percentage, between the total energy entering the room through the glazing and the incident solar energy. High selectivity corresponds to achieving high visible light transmission combined with selective filtering of UV and IR radiation.
[0005] Achieving high selectivity must not be at the expense of aesthetics, and in particular color. Generally, the aim is to obtain the most neutral aesthetic possible in terms of transmission, external reflection, and internal reflection. This color neutrality must also be achieved regardless of the viewing angle relative to the glazing.
[0006] Known selective glazing comprises transparent substrates coated with a functional coating. Functional coatings comprising silver-based functional layers are generally more efficient in terms of selectivity compared to other known infrared-reflecting functional coatings such as coatings comprising conductive oxide-based layers, layers based on other metallic layers, or IR-absorbing layers.
[0007] When seeking to increase selectivity, the aim is to selectively reduce transmission in the infrared region (above 750 nm). One solution consists of to increase the number of silver-based functional layers. When determining the transmission curves as a function of wavelength, the following observations are made. The greater the number of silver-based functional layers, the sharper the transmission profile is over the visible wavelength range and the narrower the base of the peak corresponding to absorption. However, the cutoff is not sharp and often extends into the visible red wavelength range. Absorption therefore becomes significant at the extreme values of the visible spectrum corresponding to red absorption around 700 nm.
[0008] Absorbing in this visible region does not lead to a significant decrease in light transmission. This phenomenon is explained by the fact that the determination of light transmission takes into account the sensitivity of the human eye, or visual acuity.The eye's sensitivity to wavelength gradually decreases on either side of a maximum between 495 and 555 nanometers (nm). The human eye is therefore less sensitive to the extreme wavelengths of the visible spectrum, particularly those in the 630 to 780 nm range. Light transmission is only slightly affected by absorption between 630 and 780 nm because absorption occurs in a region where the human eye is less sensitive. However, absorption in this range significantly reduces the total energy entering the room or vehicle, thus lowering the solar factor without significantly decreasing light transmission.
[0009] In conclusion, the small decrease in light transmission coupled with the large reduction in energy transmission leads to a clear improvement in selectivity.
[0010] By way of example, the selectivities achieved in double glazing thanks to functional coatings comprising 1, 2, 3 or 4 silver-based layers are respectively approximately 1.2, 1.7, 2.0 and 2.25.
[0011] However, absorption in the visible red wavelength range between 630 and 780 nm has a significant impact on color perception. When light rays reach the eyes, they are captured by photoreceptors in the retina. There are three types of photoreceptors, each with spectral sensitivity to a specific region of the color spectrum: cones more sensitive to blue light (peak centered at approximately 420 nm), others to green light (peak centered at 530 nm), and a third type of cone to red light (peak centered at 565 nm). Absorbing light between 630 and 780 nm, that is, in the region corresponding to the predominant absorption of red light, results in the perception of complementary colors, particularly green. In conclusion, reducing transmission in the red range gives the glazing a green tint in transmission.
[0012] To limit this green coloration, several approaches are possible. The traditional approach to achieving both high selectivity and color neutrality involves developing increasingly complex functional coatings. These functional coatings comprise several silver-based metallic functional layers, each sandwiched between two dielectric coatings comprising several dielectric layers. Such glazing improves solar protection while maintaining high light transmission.
[0013] Colors are optimized by exploiting optical interference phenomena. However, for high levels of selectivity, this solution is insufficient. A compromise between neutrality and selectivity must then be found.
[0014] To characterize the color of a material or glazing in transmission, reflection, or absorption, the reflection, transmission, or absorption spectrum is determined. From this spectrum, the color can be defined by the parameters a* and b* in the Lab system with illuminant D65 and CIE 2° 1931 as the observer.
[0015] In this case, a material or glazing with an excessively blue-green appearance means that the values of a* are too negative. If we consider transmitted colors, this means that the values of a*T are too negative.
[0016] Theoretically, seeking neutrality means aiming for zero values of a* and b*. However, in practice, these results cannot be obtained. Moreover, it is preferable not to be too close to 0 in order to avoid positive values. It is preferable to have values of a*T that are less close to 0 but strictly negative rather than close to 0 but alternately positive or negative. In the latter case, undesirable changes in hue are observed, for example, between slightly red and slightly green. Consequently, if perfect neutrality is not possible, it is preferable for the color to tend towards a blue-green rather than towards red.
[0017] To achieve this, we aim to obtain negative values of a* as close to 0 as possible, particularly in transmission, and ideally at all viewing angles. The greater the desired neutrality, the lower the selectivity can be. The values of b*, on the other hand, can be positive or negative, but preferably as close to 0 as possible.
[0018] Another way to improve neutrality is by adding absorbing elements to the functional coating. However, to reduce the green coloration, it would be necessary to have elements that absorb selectively in the green range, that is, between 490 and 550 nm. By selectively absorbing in the green range, the effect of absorption in the red range is neutralized without significantly impacting light transmission and therefore without reducing selectivity.
[0019] In the absence of an element specifically absorbing the green color, in order to become less green, it is necessary to "enlarge" the transmission window towards the red in order to To capture more light, we allow a significant amount of red / infrared radiation to pass through, greatly increasing the solar factor and thus reducing selectivity. In this case, a compromise between selectivity and neutrality must be found.
[0020] Functional coatings are generally obtained by a series of deposits made by sputtering, possibly assisted by a magnetic field. Advantageously, the absorbing element should be able to be deposited using this technique.
[0021] Finally, depending on the application, the substrates constituting the glazing may need to undergo high-temperature heat treatments such as quenching or laser annealing. Advantageously, the absorbing element must be able to exhibit its advantageous absorption properties while simultaneously: - when the absorbing element or the substrate carrying the absorbing element has not undergone high-temperature heat treatment and - when the absorbing element or the substrate carrying the absorbing element undergoes heat treatment at high temperature.
[0022] Obtaining the properties regardless of whether or not heat treatment is present allows for greater flexibility and simplicity in production lines. For example, it is possible to use the same cathode sequence for coatings used in both untempered and tempered applications.
[0023] Traditionally used visible-light absorbing elements include, for example, metallic coatings or coatings based on metal nitrides. These coatings do not absorb specifically in the green range but rather relatively homogeneously across the entire visible spectrum (350-750 nm). Consequently, they do not allow for the selective neutralization of the green color. These absorbing coatings do not provide both high selectivity and good neutrality.
[0024] Document WO2018 / 197821 describes colored glazing composed of a clear glass substrate onto which a colored coating is deposited. The coating comprises metallic nanoparticles in an inorganic matrix of an oxide of at least one element selected from the titanium, silicon, or zirconium group, for example TiOx:Ag. The colored coating exhibits an absorption peak whose maximum is between 350 and 800 nm. The position of the absorption peak maximum varies depending on the thickness of the colored coating, the oxidation levels, or the density of the metallic particles.
[0025] Document WO2019 / 239312 discloses functional coatings comprising a discontinuous silver layer encapsulated in an inorganic matrix based on niobium or silicon oxide.
[0026] Document WO2011 / 123402 discloses functional coatings comprising a discontinuous silver layer located between a dielectric layer of stannate zinc and a layer based on a nickel and chromium alloy (“Inconel”) or between a layer of zinc oxide and a layer of titanium.
[0027] These documents all disclose different layered elements comprising a discontinuous silver layer comprising nanometric silver particles encapsulated in different environments such as an inorganic matrix or two dielectric and / or metallic layers.
[0028] These documents do not disclose absorbent layer elements that allow satisfactory absorption properties to be obtained in green, both before and after heat treatment. These layer elements do not allow satisfactory absorption properties to be obtained in green, both before and after heat treatment.
[0029] Finally, nothing in these documents indicates how to modulate the absorption in the preferred range between 475 and 590 nm.
[0030] The object of the invention is to develop new absorbing elements that specifically absorb the green color.
[0031] By selectively absorbing in the green range, the effect of red light absorption is neutralized without significantly impacting light transmission and therefore without reducing selectivity. Using the absorbing layered element according to the invention, at the same level of selectivity, allows for improved neutrality at 0° and at angles.
[0032] The applicant has developed a new absorbing layered element. This layered element comprises a discontinuous silver layer containing silver nanoparticles capable of generating a plasmonic effect. The plasmonic effect consists of a vibration of the electron cloud of nanoparticles when they are subjected to an electromagnetic field. "Plasmonic absorption" refers to absorption related to plasmonic resonance effects of silver nanoparticles in a dielectric matrix. The specific absorption of the layered element according to the invention results from the plasmonic effect generated by the interactions between these nanoparticles and their specific environment.
[0033] The invention relates to a material comprising a transparent substrate coated with a layered element comprising, starting from the substrate: - a first dielectric layer, - a discontinuous silver-based layer comprising nanometric silver particles, - a second dielectric layer, characterized in that: The discontinuous silver-based layer is located in contact below and / or above a carbon-based layer.
[0034] The material may also have the following characteristics alone or in combination: - The discontinuous silver-based layer has an equivalent thickness of less than 1.5 nm, - the surface filling of the discontinuous layer by nanoparticles is between 10% and 60%, - the nanoparticles have a median equivalent diameter between 1 and 10 nm and / or a median interparticle distance between 3 and 10 nm, - the nanoparticle density is greater than 1xlO3 particles.pm 2, - the discontinuous silver-based layer is located in contact with, or separated from, the first dielectric layer and / or the second dielectric layer only by the carbon layer. - the first and / or second dielectric layer are chosen from layers containing silicon, - the first and / or second dielectric layer are chosen from nitride, oxide or oxynitride layers, - the first dielectric layer and the second dielectric layer are silicon nitride-based layers, - the first dielectric layer and / or the second dielectric layer has a thickness between 2 and 20 nm, - the sum of the thicknesses of the first dielectric layer and the second layer containing silicon is between 4 and 40 nm, - the carbon layer has an equivalent thickness of less than 2 nm, - the substrate is coated with a functional coating comprising at least one continuous silver-based functional metallic layer located between two dielectric coatings comprising at least one dielectric layer, and in that the layered element is located within a dielectric coating, - the functional coating comprises successively, starting from the substrate, an alternation of two continuous silver-based functional metallic layers, named from the substrate first and second functional layers, and three dielectric coatings named from the substrate D1, Di2 and Di3, such that each continuous functional metallic layer is disposed between two dielectric coatings, the layered element is located in the dielectric coating D1 and / or in the dielectric coating Di2, - the first and / or second continuous functional layer has a thickness between 7 and 20 nm, - the substrate is made of glass, particularly soda-lime silico-glass or polymeric organic matter, - each dielectric coating located below a functional layer comprises a zinc oxide-based layer situated below, in contact with, or separated by a blocking layer from the functional layer and having a thickness greater than or equal to 3 nm, - each dielectric coating located above a functional layer includes a zinc oxide-based layer located above, in contact with, or separated by a blocking layer from the functional layer.
[0035] The invention also relates to glazing comprising at least one material according to the invention and an additional substrate assembled in the form of multiple glazing.
[0036] The layered element is deposited by magnetic field-assisted sputtering (magnetron process). This means that all the layers are deposited by magnetic field-assisted sputtering.
[0037] According to the invention, a layer of a material is considered continuous when the layer is present over the entire surface and consists of a non-zero thickness of the material in question over the entire surface. In contrast, a discontinuous layer is not present over the entire surface.
[0038] For each material and depending on its environment, there is a minimum thickness below which the layer will not be continuous. For silver-based layers deposited by sputtering, the minimum thickness below which a continuous layer is not obtained is approximately 5 nm. This means that when the sputtering device is configured to produce a continuous layer 5 nm thick, the actual result is a discontinuous layer containing areas without silver and areas with silver particles thicker than 5 nm. The arrangement of these nanometric silver particles forms nanometric patterns.
[0039] The nanoparticles according to the invention are arranged in a plane. This means that there are no multiple superimposed particles within the thickness of the silver-based discontinuous layer. The silver-based discontinuous layer is therefore of a single-particle thickness. Complete characterization can thus be performed in a plane parallel to the substrate at the level of the discontinuous layer.
[0040] According to the invention, the nanometric particles (or nanoparticles) of silver are in contact with a layer of carbon and encapsulated between two particular dielectric layers.
[0041] The applicant has discovered that the advantageous absorption properties, before and after heat treatment, of the layered element of the invention depend directly on this environment. Indeed, this environment, in contact with the discontinuous silver-based layer, allows for maximum absorption in the green region, particularly in the wavelength range from 490 to 550 nm.
[0042] The applicant also discovered that the morphology and distribution of the nanometric silver particles also strongly influence the resonance and absorption properties. Among the influencing characteristics are: - the size of the nanoparticles, - the density of nanoparticles, - surface filling, - interparticle distance, - shape such as aspect ratio and - height of nanoparticles.
[0043] The characterization of the discontinuous layer morphology can be carried out by all modes of microscopic observation, direct or indirect, such as scanning electron microscopy, transmission electron microscopy (TEM), electron backscatter diffraction, atomic force microscopy and optical microscopy.
[0044] Preferably, the characterization of the discontinuous layer's morphology is determined by quantitative statistical analysis of TEM images. This image analysis can be performed, in particular, using scikit-image, an image processing library written in Python. The TEM images allow for a statistical study of the nanoparticle morphology. The following information can be extracted from these images: the area occupied by a particle and its equivalent diameter, its principal axes, the position of its center, the number of particles per image, and the total area occupied by all the particles. The area occupied by all the particles gives the surface filling or occupancy rate.
[0045] The size of the nanoparticles is estimated by calculating the equivalent diameter of the particles. To do this, the surface area of each particle is determined. Then, the equivalent diameter of a disk with the same surface area is calculated. Finally, the median diameter of all the particles counted in the image is determined to obtain the median equivalent diameter.
[0046] The density of nanoparticles is determined by counting the number of particles per image and relating this value per pm2 of surface (particles.pm2).
[0047] The surface filling or occupancy rate corresponds to the percentage of area occupied by all the particles out of the total area of the discontinuous layer (particles and discontinuity).
[0048] The interparticle distance corresponds to the distance between two particle centers. The median interparticle distance corresponds to the median of all interparticle distances.
[0049] The aspect ratio corresponds, for each particle, to the ratio of the major axis to the minor axis. It characterizes the elongation of a particle with a value greater than 1.
[0050] The height of the nanoparticles (hnp) is determined, to the first order assuming that the particles have straight edges, from the equivalent thickness and the surface filling with hnp = Thickness eq. / Surface filling.
[0051] TEM image analysis shows that adding the carbon layer results in more spherical silver nanoparticles. A very thin layer, on the order of a nanometer, is sufficient to impact the wavelength and full width at half maximum (FWHM) of the absorption peak, with a negligible penalty to the total absorption of the product. This configuration contributes to obtaining a narrower FWHM in the green region and thus minimizes its impact on the total transmission of the product. The impact of the carbon layer is visible on the absorption peak of the unheat-treated layered element and also after high-temperature heat treatment such as annealing at 650°C. The presence of the carbon layer allows for more effective neutralization of the green color.
[0052] The carbon layer is deposited with a neutral gas, preferably argon. The carbon layer can be deposited without oxygen. In one embodiment, the dielectric layers of the layered element can also be deposited without oxygen. Not using oxygen and / or nitrogen in the carbon layer, and a fortiori in the layered element, reduces the dependence on heat treatment. No shift in the absorption peak and / or diffusion and / or attenuation of the color neutralization correction are observed between a heat-treated and an unheat-treated layered element.
[0053] The layered element exhibits its advantageous absorption properties both: - when the layered element or the substrate bearing the layered element has not undergone high-temperature heat treatment and - when the layered element or the substrate bearing the layered element undergoes high-temperature heat treatment.
[0054] According to the invention, the equivalent thickness of a discontinuous layer is defined as the thickness of that layer if it were continuous. This equivalent thickness can, for example, be approximated by an analysis of the layered element by secondary ion mass spectrometry (“SIMS”) microprobe. This makes it possible to quantify the amount of substance in terms of the number of silver atoms per unit area. This value can then be converted into an equivalent thickness. To obtain an equivalent thickness, the thickness is determined for a low flow rate. corresponding. Then, a rule of three is applied to the film speed to obtain the desired equivalent thickness. For example, a thickness of 10 nm is measured for a silver layer deposited at a film speed of 10 m / min. Therefore, if we want to obtain a silver layer with an equivalent thickness of 1 nm, we would choose a film speed of 10 m / min.
[0055] The discontinuous silver-based layer has an equivalent thickness: - greater than 0.3 nm, greater than 0.4 nm, greater than 0.5 nm, greater than 0.6 nm, greater than 1 nm, and / or - less than 5 nm, less than 3.0, less than 2.0 nm, less than 1.5 nm, less than 1.0 nm.
[0056] Advantageously, the discontinuous silver-based layer has an equivalent thickness of between 0.4 and 2 nm.
[0057] For these ranges of equivalent thickness: - the position of the maximum absorption peak (resonance) shifts and goes from approximately 450 nm for a thickness of about 0.3 nm to approximately 750 nm for a thickness of about 1.5 nm, and - the amplitude of the absorption peak increases and goes from about 3.5% for a thickness of about 0.3 nm to about 25% for a thickness of about 1.5 nm.
[0058] Advantageously, it is preferable that the peak be centered between 490 and 550 nm, preferably around 515 nm, to specifically absorb in the green, and that its absorption maximum be less than 20% so as not to significantly reduce the light transmission.
[0059] The layered element of the invention makes it possible to obtain an absorption peak in the "green", that is to say, whose absorption peak is advantageously centered between approximately 510 and 530nm, whose width at half maximum is as small as possible in order to minimize its impact on light transmission and whose intensity is between 10 and 15%.
[0060] The preferred characteristics that appear in the rest of the description are applicable both to the material according to the invention and, where applicable, to the glazing, devices or process according to the invention.
[0061] Unless otherwise stated, the thicknesses referred to in this document are physical thicknesses.
[0062] In this description, unless otherwise indicated, the expression "based on", used to describe a material or layer as to what it contains, means that the mass fraction of the constituent it comprises is at least 50%, in particular at least 70%, preferably at least 90%.
[0063] Throughout this description, the substrate according to the invention is considered to be laid horizontally. The coating or layered element is deposited on top of the substrate. The meanings of the expressions "on top," "below," and "below" are unclear. The terms "above" and "below" should be considered in relation to this orientation. Unless otherwise specified, the expressions "above" and "below" do not necessarily mean that two layers and / or coatings are in contact with each other. When it is specified that a layer is deposited "in contact" with another layer or coating, this means that there cannot be one (or more) layer(s) interposed between these two layers (or layer and coating).
[0064] The coating or layered element is deposited by magnetic field-assisted sputtering (magnetron process). According to this advantageous embodiment, all the layers of the coating or layered element are deposited by magnetic field-assisted sputtering.
[0065] All the described luminous characteristics are obtained according to the principles and methods of European standard EN 410 relating to the determination of the luminous and solar characteristics of glazing used in building glass. Sunlight entering a building is considered to travel from the outside in.
[0066] According to the invention, the following luminous characteristics are measured with respect to illuminant D65 at 2° perpendicular to the material: - AL corresponds to the light absorption in the visible spectrum in %, - a*abs and b*abs correspond to the colors in absorption a* and b* in the L*a*b* system, after removing the substrate contribution, with the observer on the layer side, - TL corresponds to the light transmission in the visible range in %, - Rext corresponds to the external light reflection in the visible spectrum as a percentage, from the observer's perspective on the exterior space. - Rint corresponds to the internal light reflection in the visible spectrum as a percentage, from the observer's perspective on the interior space side. - a*T and b*T correspond to the colors in transmission a* and b* in the L*a*b* system, - a*Rext and b*Rext correspond to the reflected colors a* and b* in the L*a*b* system, observer on the outside space side. - a*Rint and b*Rint correspond to the colors in reflection a* and b* in the L*a*b* system, observer on the interior space side.
[0067] To characterize absorption, it is possible to determine the colors under absorption. For this purpose, the layered element is deposited on a 4 to 6 mm clear glass substrate. Its absorption spectrum is then determined, and the colors are calculated in the Lab system with illuminant D65 and CIE 2° 1931 as the observer. It is then possible to calculate the light absorption AL and the colorimetric parameters a*abs and b*abs.
[0068] According to the invention, the absorbing layered element must absorb specifically in the green range without having excessively high light absorption so as not to significantly impact light transmission and therefore selectivity. Neutralization is considered good when the layered element has very negative a*abs values and light absorption of less than 15%. Preferably: - a*abs is less than -5, or less than -10, and / or - b*abs varies between -10 and +10, and / or - AL is between 8 and 15%.
[0069] Another way to evaluate the neutralization efficiency is to determine the neutralization factor corresponding to the product of the light absorption AL and a*abs. The neutralization efficiency is proportional to the neutralization factor.
[0070] Different results are obtained depending on whether or not the layered element undergoes high-temperature heat treatment. When the layered element undergoes quenching-type heat treatment, neutralization factors of -100 can be achieved. When the layered element does not undergo quenching-type heat treatment, neutralization factors on the order of -40 can be achieved. Preferably, the neutralization factor is less than -50, or even less than -100.
[0071] The layered element has a thickness: - greater than or equal to 5 nm, greater than or equal to 8 nm, greater than or equal to 10 nm or greater than or equal to 15 nm, and / or - less than or equal to 100 nm, less than or equal to 30 nm, less than or equal to 20 nm or less than or equal to 15 nm. Preferably, the layered element has a thickness between 5 nm and 15 nm. The thickness of the layered element corresponds to the sum of the thicknesses of all the layers of the layered element, that is to say of the first, the second dielectric layer and the equivalent thicknesses of the discontinuous silver-based layer and the carbon layer.
[0072] The silver-based discontinuous layer comprises at least 95.0%, preferably at least 96.5%, and more preferably at least 98.0% by mass of silver relative to the mass of the discontinuous layer. Preferably, the silver-based discontinuous layer comprises less than 1.0% by mass of metals other than silver relative to the mass of the functional silver-based metallic layer. To obtain a sharp absorption peak, it is preferable to have discontinuous layers of pure or lightly doped silver. The silver particles are preferably pure silver-based.
[0073] The first and second dielectric layers of the layered element have the following characteristics, alone or in combination: - they are deposited by magnetic field-assisted sputtering, - they are chosen from the oxides, nitrides or oxynitrides of one or more elements chosen from titanium, silicon, aluminium, zirconium, tin and zinc, - they have a thickness greater than 2 nm, preferably between 2 and 100 nm.
[0074] The discontinuous layer deposited above the first dielectric layer is either in direct contact or separated by a carbon layer. The discontinuous layer deposited below the second dielectric layer is either in direct contact or separated by a carbon layer. Preferably, the carbon layer is located above and in contact with the discontinuous layer.
[0075] Preferably, the first and second dielectric layers comprise silicon.
[0076] Each first or second dielectric layer in contact with the discontinuous silver-based layer or separated by a carbon layer, has a thickness greater than or equal to 2 nm, greater than or equal to 3 nm, greater than or equal to 4 nm or greater than or equal to 5 nm.
[0077] Each first or second dielectric layer in contact with the discontinuous silver-based layer or separated by a carbon layer, has a thickness less than or equal to 25 nm, less than or equal to 20 nm or less than or equal to 15 nm.
[0078] Layers comprising silicon can be selected from oxide-based, nitride-based or silicon oxynitride-based layers such as silicon oxide-based layers, silicon nitride-based layers and silicon oxynitride-based layers.
[0079] The quantities of oxygen and nitrogen in a layer are determined as atomic percentages relative to the total quantities of oxygen and nitrogen in the layer considered.
[0080] According to the invention: - Silicon oxide-based layers consist primarily of oxygen and very little nitrogen, - Silicon nitride-based layers consist primarily of nitrogen and very little oxygen, - Silicon oxynitride-based layers comprise a mixture of oxygen and nitrogen.
[0081] Silicon oxide-based layers comprise at least 90% by atomic percentage of oxygen relative to the oxygen and nitrogen in the silicon oxide-based layer. Silicon nitride-based layers comprise at least 90% by atomic percentage of nitrogen relative to the oxygen and nitrogen in the silicon nitride-based layer. Silicon oxynitride-based layers comprise 10 at 90% (excluding limits) as an atomic percentage of nitrogen relative to oxygen and nitrogen in the silicon oxynitride-based layer.
[0082] According to one embodiment, the first and second silicon layers both comprise silicon nitride-based layers.
[0083] Layers comprising silicon, containing at least 90% silicon by mass relative to the mass of all elements constituting the silicon layer other than nitrogen and oxygen, exhibit refractive indices as defined below, depending on whether they are oxide, nitride, or oxynitride layers. Silicon oxide-based layers are characterized by a refractive index at 550 nm of 1.55 or less. Silicon nitride-based layers are characterized by a refractive index at 550 nm of 1.95 or greater. Silicon oxynitride-based layers are characterized by a refractive index at 550 nm intermediate between that of a non-nitrided oxide layer and a non-oxidized nitride layer. Silicon oxynitride-based layers preferably have a refractive index at 550 nm greater than 1.55, 1.60 or 1.70 or between 1.55 and 1.95, 1.60 and 2.00, 1.70 and 2.00 or 1.70 and 1.90.These refractive indices can vary to a certain extent (±0.1) depending on the deposition conditions. Indeed, by adjusting certain parameters such as pressure or the presence of dopants, it is possible to obtain layers of varying density and therefore a variation in refractive index.
[0084] The layers comprising silicon may comprise or be made of elements other than silicon, oxygen and nitrogen. These elements may be selected from aluminium, boron, titanium and zirconium.
[0085] The layers comprising silicon may comprise at least 50%, at least 60%, at least 65%, at least 70%, at least 75.0%, at least 80% or at least 90% by mass of silicon relative to the mass of all the elements constituting the layer comprising silicon other than nitrogen and oxygen.
[0086] Preferably, the layer comprising silicon comprises at most 35%, at most 20% or at most 10% by mass of elements other than silicon relative to the mass of all the elements constituting the layer comprising silicon other than oxygen and nitrogen.
[0087] The silicon-based layer may comprise at least 2%, at least 5.0% or at least 8% by mass of aluminium relative to the mass of all the elements constituting the silicon oxide-based layer other than oxygen and nitrogen.
[0088] Silicon zirconium nitride-based layers SixZryNz are among the layers comprising silicon, in particular silicon nitride-based layers. The refractive index of silicon zirconium nitride-based layers increases with increasing proportions of zirconium in said layer.
[0089] Silicon nitride-based layers may include aluminum and / or zirconium. Such layers may include, in atomic proportions relative to the atomic proportions of Si, Zr, and Al: - 50 to 98%, 60 to 90%, 60 to 70% atomic silicon, - 0 to 10%, 2 to 10% atomic aluminum, -0 to 30%, 10 to 40% or 5 to 30% atomic zirconium.
[0090] According to the invention, the first and second silicon layers are deposited from a silicon metal target. Deposition takes place in an atmosphere containing an optimized amount of oxygen and nitrogen to obtain the desired properties. The deposition atmosphere comprises a mixture of noble gases (He, Ne, Xe, Ar, Kr) and oxygen and / or nitrogen. The noble gas is preferably argon. The following parameters define the conditions for sputtering deposition:
[0091] - the deposition pressure, - the composition of gases in volumetric flow rate (unit sccm "standard cubic centimeter per minute").
[0092] The carbon-based layer comprises at least 95.0%, preferably at least 96.5% and better still at least 98.0% by mass of carbon relative to the mass of the carbon-based layer.
[0093] The carbon-based layer according to the invention can be obtained by magnetic field-assisted sputtering, for example using a graphite target. The atmosphere in the deposition chamber comprises a neutral gas, preferably argon.
[0094] According to one embodiment, the carbon-based layer has a thickness: - less than 5.0 nm, less than 4.0 nm, less than 3.0 nm, less than 2.0 nm, less than 1.0 nm, less than or equal to 0.9 nm, less than 0.8 nm and / or - greater than or equal to 0.1 nm, greater than or equal to 0.2 nm, greater than or equal to 0.3 nm.
[0095] According to one embodiment, the carbon layer has a thickness strictly less than 1.0 nm, preferably between 0.2 and 0.8 nm. These thin carbon layers do not significantly alter the absorption in the visible range.
[0096] The layered element can be used alone.
[0097] The layered element can be used in a coating comprising other Coatings for correcting or modifying color. Examples of such coatings include infrared-reflecting functional coatings comprising metallic, nitrided, or conductive oxide-based infrared-reflecting functional layers. The invention is intentionally not limited to these functional coatings. insofar as the layered element can be used on any substrate to correct or give a particular color.
[0098] The functional layer is preferably a layer capable of acting on solar radiation and / or long-wavelength infrared radiation. These functional layers are preferably silver-based metallic functional layers.
[0099] The layered element is particularly suitable for these functional coatings comprising in particular several silver-based functional layers insofar as they exhibit a non-negligible absorption in the red generating a green tint in transmission.
[0100] To reflect infrared radiation in a significant way, the silver layer must be continuous. Discontinuous silver layers according to the invention are not considered to be functional infrared-reflecting layers.
[0101] The functional coating comprises at least one functional layer. The functional coating comprises successively from the substrate an alternation of n functional metallic layers, in particular silver-based functional layers and (n+1) dielectric coatings, each coating comprising at least one dielectric layer, such that each functional metallic layer is disposed between two dielectric coatings.
[0102] Unless otherwise stated, the thicknesses referred to in this document without further specification are physical, real, or geometric thicknesses denoted Ep and are expressed in nanometers (and not optical thicknesses). The optical thickness Eo is defined as the physical thickness of the layer in question multiplied by its refractive index at a wavelength of 550 nm: Eo = n*Ep. Since the refractive index is a dimensionless value, the unit of the optical thickness can be considered to be the same as that chosen for the physical thickness.
[0103] According to the invention, a dielectric coating corresponds to a sequence of layers comprising at least one dielectric layer, located between the substrate and the first functional layer (Dil), between two functional layers (Di2 or Di3) or above the last functional layer (Di4).
[0104] If a dielectric coating is composed of several dielectric layers, the optical thickness of the dielectric coating corresponds to the sum of the optical thicknesses of the different dielectric layers constituting the dielectric coating. If a dielectric coating includes an absorbing layer for which the refractive index at 550 nm includes a non-zero (or non-negligible) imaginary part of the dielectric function, for example a metallic layer, the thickness of this layer is not taken into account for the calculation of the optical thickness of the dielectric coating.
[0105] The thicknesses of the blocking layers are not taken into account for the calculation of the optical thickness of the dielectric coating.
[0106] When a dielectric coating includes a layered element, the thickness of the dielectric layers of the layered element is taken into account in the calculation of the optical or physical thickness of the dielectric coating.
[0107] For the purposes of the present invention, the terms "first", "second", and "third" for functional layers or dielectric coatings are defined starting from the substrate carrying the stack and referring to the layers or coatings with the same function. For example, the functional layer closest to the substrate is the first functional layer, the next one moving away from the substrate is the second functional layer, and so on.
[0108] The functional coating comprises two continuous silver-based metallic functional layers (Fl and F2), each disposed between two dielectric coatings (Dil, Di2, Di3). The functional coating may comprise only two continuous silver-based metallic functional layers.
[0109] The silver-based metallic functional layers comprise at least 95.0%, preferably at least 96.5%, and more preferably at least 98.0% by mass of silver relative to the mass of the functional layer. Preferably, a silver-based metallic functional layer comprises less than 1.0% by mass of metals other than silver relative to the mass of the silver-based metallic functional layer.
[0110] The silver-based metallic functional layers have a thickness: - greater than 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm or 16 nm, and / or - less than 25 nm, 22 nm, 20 nm, 18 nm.
[0111] The first functional layer has a thickness between 7 and 20 nm or between 10 and 18 nm. The second functional layer has a thickness between 7 and 20 nm or between 10 and 18 nm.
[0112] The blocking layers traditionally serve to protect the functional layers from possible degradation during the deposition of the upper dielectric coating and during possible high-temperature heat treatment, such as annealing, bending and / or quenching.
[0113] The blocking layers are chosen from: - metallic coatings based on a metal or metallic alloy, metallic nitride coatings, and metallic oxynitride coatings of one or more elements selected from titanium, zinc, tin, nickel, chromium, and niobium, - the metallic oxide layers of one or more elements chosen from titanium, nickel, chromium and niobium.
[0114] The blocking layers may in particular be layers of Ti, TiN, TiOx, Nb, NbN, Ni, NiN, Cr, CrN, NiCr, NiCrN, SnZnN. When these blocking layers are deposited in metallic, nitrided or oxynitrided form, these layers may undergo partial or total oxidation depending on their thickness and the nature of the layers surrounding them, for example, at the time of deposition of the next layer or by oxidation in contact with the underlying layer.
[0115] According to advantageous embodiments of the invention, the blocking layer(s) satisfy one or more of the following conditions: - each functional metallic layer is in contact with at least one blocking layer chosen from a blocking sublayer and a blocking overlayer, and / or - each functional metallic layer is in contact with a blocking overlayer, and / or - the thickness of each blocking layer is at least 0.05 nm, or between 0.05 and 2.0 nm, or between 0.05 and 1 nm, and / or - the sum of the thicknesses of all the blocking layers is greater than or equal to 0.5 nm or greater than or equal to 0.8 nm or greater than or equal to 1.0 nm, and / or - the sum of the thicknesses of all the blocking layers is less than or equal to 5.0 nm or less than or equal to 3.0 nm or less than or equal to 2.0 nm.
[0116] For the blocking layers, the thicknesses correspond to the thicknesses of the layers as deposited, i.e. before heat treatment or before any oxidation during the deposition of the overlying layer.
[0117] According to the invention, the blocking layers are considered not to be part of a dielectric coating. This means that their thickness is not taken into account in the calculation of the optical or geometric thickness of the dielectric coating in contact with them.
[0118] For the purposes of this invention, "dielectric layer" means a material that is "non-metallic" in nature, i.e., not a metal. In the context of this invention, the term refers to a material having an n / k ratio over the entire visible wavelength range (from 380 nm to 780 nm) equal to or greater than 5. n denotes the actual refractive index of the material at a given wavelength, and k represents the imaginary part of the refractive index at a given wavelength; the n / k ratio being calculated at a given wavelength as identical for n and k.
[0119] Preferably, each dielectric coating consists solely of one or more dielectric layers.
[0120] For the purposes of this invention, "dielectric coating" means that there may be a single layer or several layers of different materials within the coating. A "dielectric coating" according to the invention It mainly comprises dielectric layers. However, according to the invention, these coatings can also comprise layers of other nature, in particular absorbent layers, for example metallic ones.
[0121] A "same" dielectric coating is considered to be located: - between the substrate and the first functional layer, - between each silver-based functional metallic layer, - above the last functional layer (the one furthest from the substrate).
[0122] The coatings have a thickness greater than 15 nm, preferably between 15 and 200 nm.
[0123] The dielectric layers of the coatings have the following characteristics, alone or in combination: - They are deposited by magnetic field-assisted sputtering, - They are chosen from oxides, nitrides or oxynitrides of one or more elements chosen from titanium, silicon, aluminium, zirconium, tin and zinc, - they have a thickness greater than 2 nm, preferably between 2 and 100 nm.
[0124] Dielectric layers, in addition to their optical function, can have various other functions. The choice of the type and position of the dielectric layers within the dielectric coating depends on this function. Examples include the following functions: - Stabilizing or wetting layers located in the immediate vicinity of silver-based functional layers such as zinc oxide-based layers, - Smoothing layers located below wetting layers such as tin oxide-based layers, - barrier layers or layers with optical function.
[0125] A single dielectric layer generally performs several functions. Indeed, each dielectric layer plays an optical role that depends on its refractive index and its thickness.
[0126] The dielectric layers are conventionally chosen from oxide-based, nitride-based, or oxynitride-based layers. Oxide-based layers of one or more elements consist essentially of oxygen and very little nitrogen. In particular, oxide-based layers comprise at least 90% oxygen by atomic percentage relative to the oxygen and nitrogen in said layer. Nitride-based layers consist essentially of nitrogen and very little oxygen. Nitride-based layers comprise at least 90% nitrogen by atomic percentage relative to the oxygen and nitrogen in said layer. Oxynitride-based layers comprise a mixture of oxygen and nitrogen. Oxynitride-based layers of silicon comprise 10 to 90% (excluding terminals) in atomic percentage of nitrogen relative to oxygen and nitrogen in said layer.
[0127] The amounts of oxygen and nitrogen in a layer are determined as atomic percentages relative to the total amounts of oxygen and nitrogen in the layer considered.
[0128] The dielectric layers are conventionally chosen from: - layers comprising silicon, aluminum and / or zirconium, possibly doped with at least one other element, - tin oxide-based layers, - titanium oxide-based layers, - zinc oxide-based layers.
[0129] Preferably, the silver-based functional layer is located above a dielectric layer, referred to as a stabilizing or wetting layer, made of a material suitable for stabilizing the interface with the functional layer. These layers are generally zinc oxide-based.
[0130] Preferably, the silver-based functional layer is located beneath a dielectric layer, referred to as a stabilizing or wetting layer, made of a material suitable for stabilizing the interface with the functional layer. These layers are generally zinc oxide-based.
[0131] Zinc oxide-based layers may comprise at least 80% or at least 90% by mass of zinc relative to the total mass of all elements constituting the zinc oxide-based layer, excluding oxygen and nitrogen.
[0132] Zinc oxide-based layers may comprise one or more elements selected from aluminium, titanium, niobium, zirconium, magnesium, copper, silver, gold, silicon, molybdenum, nickel, chromium, platinum, indium, tin and hafnium, preferably aluminium.
[0133] Zinc oxide-based layers may optionally be doped with at least one other element, such as aluminium.
[0134] A priori, the zinc oxide-based layer is not nitrided, however traces may exist.
[0135] The zinc oxide-based layer comprises, in increasing order of preference, at least 80%, at least 90%, at least 95%, at least 98% or at least 100%, by mass of oxygen relative to the total mass of oxygen and nitrogen.
[0136] The dielectric coating located between the substrate and the first functional metallic layer and / or one or each dielectric coating located above the first silver-based functional layer comprises a zinc oxide-based layer comprising at least 80% by mass of zinc relative to the mass of all elements other than oxygen.
[0137] Preferably, each dielectric coating comprises a zinc oxide-based layer comprising at least 80% by mass of zinc relative to the mass of all elements other than oxygen.
[0138] Preferably, the dielectric coatings located directly below a continuous silver-based functional metallic layer comprise at least one zinc oxide-based dielectric layer, optionally doped with at least one other element, such as aluminum. The metallic functional layer deposited above a zinc oxide-based layer is either in direct contact or separated by a blocking layer.
[0139] Preferably, the dielectric coatings located directly above a continuous silver-based functional metallic layer comprise at least one zinc oxide-based dielectric layer, optionally doped with at least one other element, such as aluminum. The metallic functional layer deposited below a zinc oxide-based layer is either in direct contact or separated by a blocking layer.
[0140] The zinc oxide layers have a thickness: - of at least 1.0 nm, at least 2.0 nm, at least 3.0 nm, at least 4.0 nm or at least 5.0 nm, and / or - of at most 25 nm, of at most 10 nm or of at most 8.0 nm.
[0141] Preferably, the material comprises one or more layers based on tin oxide, preferably zinc oxide and tin.
[0142] Tin oxide-based layers comprise at least 20% by mass of tin relative to the mass of elements other than oxygen or nitrogen. Zinc tin oxide-based layers comprise at least 20% by mass of tin relative to the total mass of zinc and tin. The zinc tin oxide-based layer comprises, relative to the total mass of zinc and tin, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, or at least 80% by mass of tin. Preferably, the zinc tin oxide-based layer comprises 40 to 80% by mass of tin relative to the total mass of zinc and tin.
[0143] The tin oxide-based layer has a thickness of: - greater than 5 nm, greater than 10 nm, greater than 15 nm, greater than 20 nm or greater than 25 nm, - less than 50 nm, less than 40 nm or less than 35 nm.
[0144] The dielectric coating located between the substrate and the first continuous functional metallic layer and / or one or each of the dielectric coatings located above the first continuous silver-based functional layer comprises a tin oxide-based layer, preferably a zinc tin oxide-based layer comprising at least 20% by mass of tin relative to the total mass of zinc and tin. Each coating dielectric may comprise a layer of tin oxide, preferably based on zinc oxide and tin comprising at least 20% by mass of tin relative to the total mass of zinc and tin.
[0145] Dielectric coatings may include layers comprising silicon as defined for the layered element.
[0146] Each layer comprising silicon has a thickness greater than or equal to 2 nm, greater than or equal to 3 nm, greater than or equal to 4 nm or greater than or equal to 5 nm.
[0147] Each layer comprising silicon has a thickness less than or equal to 25 nm, less than or equal to 20 nm or less than or equal to 15 nm.
[0148] Layers comprising silicon can be obtained: - by cathodic sputtering, - from a silicon metallic target or a silicon oxide-based ceramic target.
[0149] The dielectric coating furthest from the substrate may include a protective layer. These layers generally have a thickness of between 0.5 and 10 nm, preferably between 1 and 5 nm. This protective layer may be selected from a layer based on titanium, zirconium, hafnium, silicon, zinc and / or tin and mixtures thereof, this or these metals being in metallic, oxidized or nitrided form.
[0150] According to one embodiment, the protective layer is based on zirconium oxide and / or titanium, preferably based on zirconium oxide, titanium oxide or titanium oxide and zirconium.
[0151] The functional coating advantageously has one or more of the following characteristics: - each dielectric coating located below a functional layer comprises a zinc oxide-based layer situated below, in contact with, or separated by a blocking layer from the functional layer, having a thickness greater than or equal to 3 nm, - Each dielectric coating located above a functional layer comprises a zinc oxide-based layer situated above, in contact with, or separated from by a blocking layer by the functional layer, - The first functional layer has a thickness between 7 and 20 nm, - The second functional layer has a thickness between 7 and 20 nm, - The first dielectric coating (Dil) has an optical thickness between 60 and 120 nm. - the second dielectric coating Di2 has an optical thickness between 120 and 250 nm, - the third dielectric coating Di3 has an optical thickness between 40 and 120 nm.
[0152] The dielectric coatings of the functional coating may have the following characteristics alone or in combination: The first dielectric coating Dil comprises, in this order: - a layer based on silicon nitride or titanium oxide, 0 to 20 nm thick, - the layered element, - a layer based on zinc and tin oxide, 0 to 15 nm thick, - a zinc oxide-based layer of 2 to 12 nm, The second dielectric coating Di2 comprises, in this order: - a zinc oxide-based layer of 2 to 12 nm, - a silicon nitride-based layer of 15 to 100 nm, - a layer based on zinc and tin oxide, 0 to 20 nm thick, - a zinc oxide-based layer of 2 to 12 nm, The third dielectric coating Di3 comprises, in this order: - a zinc oxide-based layer of 2 to 12 nm, - one or more layers based on silicon nitride, the thickness of all these layers based on silicon nitride is 15 to 75 nm or 20 to 45 nm, - a top protective layer of 0 to 5 nm, all these thicknesses being physical thicknesses.
[0153] The material, i.e. the coated transparent substrate, is intended to undergo high-temperature heat treatment. Therefore, the layered element (or functional coating) and the substrate have preferably been subjected to high-temperature heat treatment such as quenching, annealing, or bending.
[0154] The material of the invention has the advantage that the advantageous properties are obtained even when the material coated with the layered element or the layered element alone has not undergone high-temperature heat treatment. The materials according to the invention can be used interchangeably: - as deposited, that is to say without having been subjected to any high-temperature heat treatment; in this case, neither the substrate coated with the stack, nor the stack alone, has undergone high-temperature heat treatment. - treated by laser radiation, in this case, only the stack undergoes high-temperature heat treatment. - treated by annealing or quenching, in this case the substrate and the stack undergo heat treatment at high temperature.
[0155] As explained previously, according to the invention the properties must be obtained even when the layered element or the substrate carrying the stack has not undergone high-temperature heat treatment.
[0156] The present invention therefore relates to the unheat-treated material. The layered element may not have undergone heat treatment at a temperature above 500°C, preferably 300°C.
[0157] The present invention also relates to the heat-treated material. The heat treatments are chosen from: - annealing, for example rapid annealing, - quenching and / or bending.
[0158] The material, i.e., the transparent substrate coated with the layered element, may have undergone high-temperature heat treatment. The layered element and the substrate may have been subjected to high-temperature heat treatment such as quenching, annealing, or bending.
[0159] It is also possible to heat-treat only the layered element. In this case, only the layered element may have undergone heat treatment.
[0160] In both cases, the layered element may have undergone heat treatment at a temperature above 300 °C, preferably 500 °C. The heat treatment temperature (at the stacking level) is above 300 °C, preferably above 400 °C, and better above 500 °C.
[0161] According to the invention, it is possible to perform a rapid thermal process ("Rapid Thermal Process") such as laser or flash lamp annealing. Rapid thermal annealing is described, for example, in applications WO2008 / 096089 and WO2015 / 185848. In these cases, only the layered element is subjected to heat treatment. During this type of treatment, each point of the layered element is brought to a temperature of at least 300°C while maintaining a temperature of 150°C or less at every point on the substrate face opposite to that on which the layered element is located. This process has the advantage of heating only the layered element, without significant heating of the entire substrate.
[0162] In the case of laser treatment, the coated materials can be treated using a laser line formed from InGaAs laser diode or Yb:YAG disk laser sources. These continuous sources emit at a wavelength between 900 and 1100 nm. The laser line has a length of approximately 3.3 m, equal to the width 1 of the substrate, and an average full width at half maximum (FWHM) between 45 and 100 pm.
[0163] The materials are arranged on a roller conveyor so as to move along an X direction, parallel to its length. The laser line is fixed and positioned above the coated surface of the substrate with its longitudinal direction Y extending perpendicularly to the X direction of substrate movement, i.e., along the width of the substrate, extending over its entire width. The position of the laser line's focal plane is adjusted to be within the thickness of the functional coating when the substrate is positioned on the conveyor. The surface power of the laser line at the focal plane is less than 100kW / cm2. The substrate was moved under the laser line at a speed of approximately 8 m / min.
[0164] The layered element may therefore have been subjected to rapid thermal annealing in which each point of the stack is brought to a temperature of at least 300 C while maintaining a temperature less than or equal to 150 C at every point of the substrate face opposite to that on which the layered element is located.
[0165] It is also possible to combine heat treatments. For example, it is possible to carry out rapid thermal annealing followed by quenching.
[0166] The layered element and the substrate may have been subjected to heat treatment at a high temperature exceeding 500 °C, such as quenching, annealing, or bending. The substrate coated with the stack may be bent or tempered glass.
[0167] The transparent organic substrates according to the invention may also be made of polymer, rigid or flexible. Examples of suitable polymers according to the invention include, in particular: - polyethylene, - polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN); - polyacrylates such as polymethyl methacrylate (PMMA); - polycarbonates; - polyurethanes; - polyamides; - polyimides; - fluorinated polymers such as fluoroesters like ethylene tetrafluoroethylene (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), ethylene chlorotrifluoroethylene (ECTFE), fluorinated ethylene-propylene copolymers (FEP); - photocurable and / or photopolymerizable resins, such as thiolene, polyurethane, urethane-acrylate, polyester-acrylate resins and - polythiourethanes.
[0168] The substrate is preferably a sheet of glass or glass-ceramic.
[0169] The substrate is preferably transparent. The substrate is preferably colorless (in which case it is clear or extra-clear glass) or colored, for example blue, gray, or bronze. The glass is preferably soda-lime silicate glass, but it may also be borosilicate or aluminoborosilicate glass.
[0170] According to a preferred embodiment, the substrate is made of glass, in particular soda-lime silico-glass or of polymeric organic matter.
[0171] The substrate advantageously has a dimension greater than or equal to 1 m, or even 2 m and even 3 m. The thickness of the substrate generally varies between 0.5 mm and 19 mm, preferably between 0.7 and 9 mm, in particular between 2 and 8 mm, or even between 2.8 and 6 mm. The substrate may be flat or convex, or even flexible.
[0172] The invention also relates to glazing comprising at least one material according to the invention. The invention relates to glazing that can be in the form of monolithic, laminated and / or multiple glazing, in particular double glazing or triple glazing.
[0173] Conventionally, the faces of a glazing are designated from the outside of the building and by numbering the faces of the substrates from the outside towards the inside of the dwelling or room it equips. This means that the incident sunlight passes through the faces in ascending order of their number.
[0174] Known selective glazing is generally double glazing comprising the functional coating or layered element located on face 2, i.e. on the outermost substrate of the building, on its face turned towards the interlayer gas gap.
[0175] A double-glazed unit has four faces: face 1 is on the exterior of the building and therefore constitutes the outer pane of the glazing; face 4 is on the interior of the building and therefore constitutes the inner pane of the glazing; and faces 2 and 3 are on the interior of the double glazing. The functional coating or layered element according to the invention is located on face 2 or face 3.
[0176] Triple glazing has 6 faces; face 1 is on the exterior of the building and therefore constitutes the outer pane of the glazing; face 6 is on the interior of the building and therefore constitutes the inner pane of the glazing; faces 2, 3, 4, and 5 are on the interior of the double glazing. The functional coating or layered element according to the invention may be located on face 2, face 3, and / or face 5.
[0177] A laminated glazing comprises at least one structure of the type first substrate / sheet(s) / second substrate. The polymer sheet may, in particular, be based on polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyethylene terephthalate (PET), or polyvinyl chloride (PVC). The functional coating or layered element is positioned on at least one of the faces of one of the substrates.
[0178] The invention therefore relates to: - a double-glazed unit with a functional coating or layered element on surface 2, - a double-glazed, multi-pane unit with a functional coating or layered element on face 3, - a triple-glazed unit with the functional coating or layered element on face 2 and face 5, - laminated glazing with the functional coating or layered element on face 2 or 3. This glazing can be fitted on a building or a vehicle. Examples
[0179] I. Preparation of materials and layered elements
[0180] In these examples, the glass substrates are 4 mm aluminosilicate type clear glass substrates. For TEM characterization, a membrane is deposited between the substrate and the layered element. TEM characterization requires an electron-transparent substrate, such as a 15 nm thick silicon nitride membrane. The layered elements are deposited on two substrates simultaneously: on the glass substrate and on the substrate adapted for TEM analysis. The TEM-adapted substrate, which is less than 1 cm² in size and approximately 200 pm thick, is taped to the glass substrate. It is assumed that, given its size and thickness, the layered element deposition is identical on both substrates.
[0181] The dielectric layers are silicon nitride (Si3N4, n = 2.0) based layers. For the discontinuous silver layers, equivalent thicknesses are considered. The conditions for layer deposition by sputtering (so-called "magnetron cathode sputtering") are summarized in Table 1. Table 1. Layer Target Used Deposition Power Deposition Pressure Gas Si3N4 Si:Al at 92.8% wt. - (1 to 4) x 10³ mbar Ar / (Ar + N2) at 55% Ag Ag 10-50 W (2 to 8) x 10³ mbar Ar or Kr Graphite - 1.5 x 10³ mbar Ar 100%
[0182] Pds: Weight; at: Atomic
[0183] Table 2 lists the materials and physical thicknesses in nanometers (unless otherwise indicated) of each layer or coating that constitutes the coatings according to their position with respect to the substrate bearing the layered element (last line at the bottom of the table). Tab.2 Material Cp.l Inv.l Inv.2 Inv.3 EC 2nd CD Si3N4 20 20 10 20 CC* 0 1 0 1 Ag dise. Ag* 1 1 1 1 C* 0 0 1 1 lere CD Si3N4 20 20 20 20 Substrate 4mm - - - -
[0184] EC: Layered element, CD: Dielectric layer, dise.: discontinuous, C: Carbon layer, *: Equivalent thickness.
[0185] These materials can be used: - as is, that is to say without undergoing additional high-temperature heat treatment (hereinafter Ann.), - Heat treated at a high temperature carried out in a NABER oven at a temperature of 650°C for 10 minutes, hereinafter heat treated material, (hereinafter TT). II. Characterization of layers by TEM 1. Image Processing
[0186] The image analysis process is summarized in [Fig.1]. The original image ([Fig. 1]-a) is denoised using the "denoise_tv_bregman" filter from the Python "skimage" library ([Fig. 1]-b). This filter reduces the total intensity variation of the image. Next, to separate the particles from the background, an intensity threshold is determined using the Otsu method. The Otsu method calculates the image intensity histogram and determines the optimal threshold that separates this histogram into two populations with minimal within-population variance. Pixels below this intensity threshold belong to the image background (in black), and pixels above this threshold belong to the particles (in white). The resulting image is a black-and-white binarized image ([Fig. 1]-c). A color is added to separate truncated particles at the edge of the image. These count towards the filling calculation but not towards the size estimation ([Fig.l]-d). The "regionprops" function (library "skimage") extracts shape and position data for each object: area, center, major axis and minor axis, orientation ([Fig.l]-e).
[0187] 2. Characterization: No heat treatment
[0188] The first series of tests is carried out on layered elements as deposited, i.e. without heat treatment. Fig. 2 represents the TEM images corresponding respectively to Cp.l (2-a), Inv.l (2-b), Inv.2 (2-c). Figure 3 corresponds to the curves representing the probability density of the parameters (on the y-axis) as a function of: - particle sizes, in particular their equivalent diameter (on the x-axis) [Fig.3]-a, - of the eccentricity (on the x-axis) [Fig.3]-b, - of the interparticle distance (on the x-axis) [Fig.3]-c, - of the aspect ratio (on the x-axis) [Fig.3]-d. Eccentricity corresponds to the ratio of the focal length to the semi-major axis of the corresponding ellipse. Figure 4 represents the absorption spectrum as a function of wavelength. In all these figures: the continuous curve corresponds to the element in layer Cp.l, the curve of triangles corresponds to the element in layer Inv.l, the curve of points, corresponds to the element in layer Inv.2.
[0189] In [Fig.3], we can see that the Inv.l nanoparticles are more homogeneous, smaller, and closer to each other. For Inv.2 and Cp.1, similarities in size and interparticle distance are observed, but different shape distributions. The nanoparticles of Inv.2 are more homogeneous and more spherical than those of Cp.1. In terms of absorption, [Fig.4] shows that the solutions of the invention Inv.1 and Inv.2 have a shifted and finer peak compared to Cp.1. This shows a more efficient and specific absorption in the green. 3. Characterization: Heat treatment
[0190] The samples were subjected to a Naber furnace quenching heat treatment at 650°C for 10 minutes prior to characterization. Figure 5 shows the TEM images corresponding to Cp.1 (5-a), Inv.1 (5-b), and Inv.2 (5-c) respectively after heat treatment. Figure 6 corresponds to the curves representing the probability density of the following parameters: - particle sizes, in particular their equivalent diameter [Fig.6]-a, - of eccentricity [Fig.6]-b, - of the interparticle distance [Fig.6]-c, - of the aspect ratio [Fig.6]-d. Figure 7 represents the absorption spectrum as a function of wavelength. In these figures: the continuous curve corresponds to the layer element Cp.l, the curve of triangles corresponds to the element in layer Inv.l, the curve of points, corresponds to the element in layer Inv.2.
[0191] In terms of absorption, [Fig.4] shows that the solutions of the invention Inv.1 and Inv.2 have a shifted and finer peak compared to Cp.1. This shows a more efficient and specific absorption in the green. 4. Summary Table Table 3 Material Cpl. Invl. Inv2. Cpl. Invl. Inv2. Heat treatment Ann. Ann. Ann. TT TT TT Density (particles.pm2) 14200 23865 13689 13854 22565 13156 Diam. Eq. Median (nm) 4.32 3.47 4.03 4.33 3.47 4.43 Interparticle distance (nm) 6.50 5.10 6.62 6.65 5.21 6.84 Aspect ratio 1.38 1.21 1.31 1.34 1.19 1.35 Eccentricity 0.617 0.505 0.564 0.590 0.492 0.579 Area fill % 24.2 24.7 21.2 23.3 23.9 23.5 Hnp (nm) 1-2 1-2 nm 1-2 nm 1-2 nm 1-2 nm 1-2 nm
[0193] Figure 8 shows graphs illustrating: - the median diameter as a function of the median interparticle distance (8-1), - the aspect ratio as a function of surface filling (8-2), - the diameter as a function of the aspect ratio (8-3), - particle density as a function of surface filling (8-4). In these figures: The squares correspond to the element in layer Cp.l, the triangles to the element in layer Inv.l, the circles to the element in layer Inv.2, the empty shapes to represent untreated material, and the filled shapes to represent heat-treated material. It can be seen that the impact of heat treatment is greater when the carbon layer is located above the discontinuous layer.
[0194] II. Optical characterization of layered elements
[0195] The objective is to highlight the specific optical absorption characteristics of the tested layered elements. To this end, the absorption of the material, i.e., the absorption of the substrate coated with the layered element, is measured on the layer side. Then, the absorption of the substrate is subtracted.
[0196] We determine: - the position of the maximum of the absorption peak (c), - its maximum absorption (max) and - its width at half height (W), - light absorption in the visible (AL) range, - the colors (a*abs, b*abs) and - the neutralization factor Fn (AL xa*abs).
[0197] Table 4 below shows the results obtained for the materials of the invention and Cp.l. Tab.4 Cp.l Inv.l Inv.2 Inv.3 Ann. max (%) 12.6 14.6 14.1 14.8 W (nm) 445 290 355 365 c (nm) 585 525 545 530 AL 12.2 13.3 13.4 14.1 a*abs -3.4 -9.5 -6.1 -6.3 b*abs 7.8 4.4 6.5 4.5 Fn -4.1 -12.6 -8.2 -8.8 TT max (%) 13.1 14.2 15.6 15.5 W (nm) 332 230 168 328 c (nm) 560 510 435 510 AL 12.4 11.6 8.4 13.9 a*abs -5.0 -12.1 -5.1 -8.1 b*abs 9.3 -2.7 -13.7 0.3 Fn -6.3 -14.0 -4.3 -11.2
[0198] According to the invention, a good absorbent coating in green is considered to have the following characteristics, preferably in combination: - a peak centered between 490 and 550 nm, preferably around 515, - a maximum absorption rate of less than 20% - a low half-width because if the width is too large, the a* can no longer be very negative, - absorption in the visible spectrum of less than 16% - a*abs as negative as possible, preferably less than -5, -6, -7, -8, -9, or even -10, and - a b* less than +10.
[0199] Examples of the invention include a narrower absorption peak, 290 nm and 230 nm after annealing at 650°C for the inv.L. TEM images corroborate the absorption measurements. The addition of the carbon layer makes it possible to obtain nanoparticles Ag particles are more spherical, resulting in a narrower peak at mid-height. Colors a* and b* also show a greater neutralizing power of 'green'.
[0200] III. Glazing with thermally treated materials
[0201] The following table lists the materials and physical thicknesses in nanometers (unless otherwise indicated) of each layer or coating that constitutes the coatings according to their position with respect to the substrate bearing the coating (last line at the bottom of the table). Tab. 5 Ml M.2 Mcp.l Mcp.2 RD: M3 Si3N4 28.8 28.8 28.8 28.8 ZnO 9.0 9.0 9.0 9.0 CB: OB2 0.1 0.1 0.1 0.1 CF: Ag2 14.2 14.2 14.2 14.2 CR: UB2 0.1 0.1 0.1 0.1 RD: M2 ZnO 8 8 8 8 SnZnO 16 16 16 16 ECA* 0 Inv 1 0 Cpl Si3N4 57.4 57.4 57.4 57.4 ZnO 9 9 9 9 CB: OBI 1.9 1.9 1.9 1.9 CF: Agi 12.8 12.8 12.8 12.8 CB: UB1 0.1 0.1 0.1 0.1 RD: Ml ZnO 5 5 5 5 SnZnO 5 5 5 5 Si3N4 9.3 9.3 9.3 9.3 ECA* Invl 0 Cpl 0 Si3N4 5.04 5.04 5.04 5.04 SiON 12 12 12 12 Sub. mm 6.0 6.0 6.0 6.0
[0202] *ECA: Absorbent layer element
Claims
Demands
1. Material comprising a transparent substrate coated with a layered element comprising, starting from the substrate: - a first dielectric layer, - a discontinuous silver-based layer comprising nanometric silver particles, - a second dielectric layer, characterized in that: the discontinuous silver-based layer is located in contact below and / or above a carbon-based layer.
2. Material according to claim 1 characterized in that the silver-based discontinuous layer has an equivalent thickness of less than 1.5 nm.
3. Material according to any one of the preceding claims characterized in that the surface filling of the discontinuous layer by nanoparticles is between 10% and 60%.
4. Material according to any one of the preceding claims characterized in that the nanoparticles have a median equivalent diameter of between 1 and 10 nm and / or a median interparticle distance of between 3 and 10 nm.
5. Material according to any one of the preceding claims characterized in that the nanoparticle density is greater than 1xlO3 particles.pm 2.
6. Material according to any one of the preceding claims characterized in that the discontinuous silver-based layer is located in contact with, or is separated from solely by the carbon layer, the first dielectric layer and / or the second dielectric layer.
7. Material according to any one of the preceding claims characterized in that the first and / or second dielectric layer are selected from layers comprising silicon such as nitride, oxide or oxynitride layers.
8. Material according to any one of the preceding claims characterized in that the first dielectric layer and the second dielectric layer are silicon nitride-based layers.
9. Material according to any one of the preceding claims characterized in that the first dielectric layer and / or the second The second dielectric layer has a thickness between 2 and 20
10. llili. Material according to any one of the preceding claims characterized in that the carbon layer has an equivalent thickness of less than 2 nm.
11. Material according to any one of the preceding claims characterized in that the substrate is coated with a functional coating comprising at least one continuous silver-based functional metallic layer situated between two dielectric coatings comprising at least one dielectric layer and in that the layered element is situated in a dielectric coating.
12. Material according to the preceding claim characterized in that the functional coating successively comprises from the substrate an alternation of two continuous silver-based functional metallic layers named from the substrate first and second functional layers, and three dielectric coatings named from the substrate Dil, Di2 and Di3, such that each continuous functional metallic layer is disposed between two dielectric coatings, the layered element is located in the dielectric coating Dil and / or in the dielectric coating Di2.
13. Material according to any one of the preceding claims characterized in that the first and / or second continuous functional layer has a thickness between 7 and 20 nm.
14. Material according to any one of the preceding claims characterized in that the substrate is made of glass, in particular soda-lime silico-glass or of polymeric organic matter.
15. Glazing comprising at least one material according to any one of claims 1 to 14 and an additional substrate assembled in the form of multiple glazing.