CN216635690U

CN216635690U - Lighting laminated glass

Info

Publication number: CN216635690U
Application number: CN202120820117.XU
Authority: CN
Inventors: 马里奥·阿图罗·曼海姆·阿斯塔特; 王钊宇; 何塞·努涅斯-雷格罗; 贡萨洛·比斯卡拉·门多萨; 安德烈斯·费尔南多·萨缅托·桑托斯; 马西莫·米切蒂; 爱德华多·D.·蒂莫什·索拉诺
Original assignee: AGP America SA
Current assignee: AGP America SA
Priority date: 2021-01-28
Filing date: 2021-04-20
Publication date: 2022-05-31
Anticipated expiration: 2031-04-20
Also published as: DE202021100843U1

Abstract

The present application relates to an illuminated laminated glass. The lighting laminated glass includes: at least two glass layers, at least one interlayer, a lighting device, a light scattering device and SiO₂An optical barrier coating. The at least two glass layers include a first glass layer and a second glass layer. The first glass layer acts as a waveguide layer. At least one interlayer is positioned between the layers of the laminated glass and is used to bond the layers of the laminated glass. The illumination device projects light into the waveguide layer from at least a portion of the at least one end face. The light scattering means are applied on the surface of the waveguide layer. SiO 2₂The optical isolation coating is at least partially in direct contact with the waveguide layer. SiO 2₂An optical barrier coating is positioned between at least two glass layers. SiO 2₂The optical barrier coating has a porosity of less than 11%. SiO 2₂The refractive index of the optical isolation coating is less than 0.1 lower than the refractive index of the waveguide layer.

Description

Lighting laminated glass

Technical Field

The present application relates to the field of laminated automotive glass and automotive lighting.

Background

As automobile manufacturers strive to meet government regulatory requirements for fuel efficiency and emissions and to provide environmentally friendly automobiles that are increasingly demanded by the public, weight reduction has become a key strategy. Although lightweight material replacement has become an important component of this trend, we have also found that the average size of most vehicles is reduced. As cabin space shrinks, unpleasant claustrophobia reactions can result. To address this problem, manufacturers have been increasing the glass area of vehicles for several years. Natural light and increased field of view help make the passenger compartment more open.

Panoramic glass roofs have developed rapidly over the past few years and have become a very popular choice. The roof of such a vehicle consists essentially of glass. The wide panorama glass roof gives the vehicle an open ventilation feeling and a luxurious appearance. In recent years, in north america and europe, vehicle models with panoramic roof options have been sold with a percentage of vehicles with this option ranging from 30% to 40%. In china, the proportion of certain vehicle models with panoramic roof options is approaching 100%.

A problem with large glass roof vehicles is cabin lighting. It is often not possible, practical or desirable to mount a lamp near the center of the roof because of the need to route the wiring harness through the glass to provide power to the lighting fixture, the addition of a cover to hide the wiring harness from the interior of the vehicle, and the addition of black printing to hide the wiring harness from the exterior. Instead, automotive manufacturers have been mounting lights above doors, footwells, cup holders, and other locations.

LED lighting devices are increasingly used in automotive applications. From cabin ambient lighting to headlamps, the cost, reliability and intensity of LEDs have reached the point of being able to economically and efficiently replace incandescent bulbs and other conventional lighting. In fact, the service life of an LED is as long as 50000 hours, which may be longer than a vehicle.

The work of embedding LEDs in laminated glass has yielded good and bad results. A major problem is that the high intensity of LEDs is intended for general illumination. Due to the small size of the LED chips and the difficulty of including any type of lens or diffuser in the laminate, the light intensity (lumens per square meter) of the LED chips is very high. Such a bright point source may make it difficult for the driver to drive at night. Another problem is heat. Although LEDs are more energy efficient than incandescent lamps, producing much less waste heat, they still produce some heat that must be managed. Since both glass and plastic interlayers are good thermal insulation materials, overheating can occur if the LEDs are too close together. In addition, the refractive index of PVB is temperature dependent, and thus any temperature gradient created by the LED can result in undesirable optical distortion.

Another illumination method is to use the glass of the laminate itself as a waveguide.

The glass can be used as a waveguide for visible light. Glass fibers guide light by reflecting the light off the fiber walls. Light entering the end of the fiber travels along a path parallel to the outer surface of the fiber. Due to the angle, most of the light is internally reflected and remains in the fiber. The exterior of the fiber is typically coated to enhance internal reflectivity, thereby allowing light to propagate over long distances without loss.

Likewise, a flat or curved glass sheet can also be used as an optical waveguide. The refractive index of air is 1, while that of soda-lime glass is 1.52. Due to the large mismatch between the glass index and the air index, a large portion of the light propagating parallel to the main glass surface is internally reflected. Little light is emitted from the major surface.

According to this principle, a sign is formed by printing a graphic on a transparent substrate and illuminating the graphic with light from a light source projecting light onto at least one edge. The printed pattern is used to scatter light propagating the illuminated pattern within the glass. This method is well known and has been in common use for decades, possibly going back to the time of the appearance of the edison bulb.

However, the information on the sign should be visible under all lighting conditions. The illumination device is provided only to be able to see the sign in dim lighting situations. The same method can be used for general cabin lighting. However, it is important to note that if the light scattering device is visible when the device is in the closed state, the glass substrate is no longer able to effectively act as a vehicle window.

For general cabin lighting, the glass may direct light projected to the edge of the glass. At the air-glass interface of the glass, there is a high refractive index mismatch. Most of the light is reflected and remains in the glass as in an optical fiber.

In standard laminated glass, we have at least two distinct materials, plastic and glass. The refractive index of a commonly used float soda lime glass is 1.52. For clear, undistorted, non-reflective, and ghost-image viewing, it is desirable to have a uniform index of refraction throughout the thickness and layers of the laminated glass. A large mismatch will result in undesirable reflections and optical distortions. The plastic interlayer used in most automotive laminates is polyvinyl butyral (PVB), which is designed to have a refractive index of 1.48. Although PVB does not match glass perfectly, they differ by only 0.04, so in all practical applications, this difference is negligible in the viewpoint angle of incidence of the driver relative to the glass. In fact, little or no light is reflected at the vehicle interior glass/PVB interface and is not noticeable to the driver and other occupants of the vehicle. Most secondary image/ghosting problems are associated with reflections at the internal and external air-glass interfaces.

For light injected edgewise into the laminate and propagating substantially parallel to the main surfaces, it is taught by EP 2635433B 1 that two materials having refractive indices which differ by 5% or less can be considered as substantially identical materials for optical purposes. Float soda lime glass has a refractive index of 1.52, whereas ordinary PVB has a refractive index of 1.48, which differs by about 2.6%. We have also found that in order to achieve total internal reflection of incident light, for example in document US9612386B2, it is required that the refractive indices of the media differ by at least 0.08 to 0.1. In contrast, the refractive index of glass/air differs by about 42%.

At the edges of standard automotive soda-lime glass laminated with PVB matched to the standard automotive refractive index, most of the incident light traveling parallel to the major surface is reflected at the air/glass interface. Regardless of which layer the light is directed to, the entire thickness of the laminate acts as a waveguide.

In some embodiments of the prior art, light is scattered from the waveguide layer by microscopic defects created in the glass surface by a variety of means, including but not limited to chemical etching, abrasion, and laser marking. Although these surface defects may be filled and masked if a PVB interlayer is applied to the interior surface of the laminate, these methods still tend to produce visible marks on the glass as well as undesirable haze and weaken the strength of the glass, thereby increasing the likelihood of breakage.

One promising new technology employs an optical diffuser suspended in a transparent polymer matrix and printed on a substrate. A serious disadvantage of this technique is that over time the organic matrix degrades from exposure to heat, moisture and uv light. Another disadvantage is that it is difficult to apply ink to the bent glass, since the ink is destroyed by the heat of the glass bending process and must therefore be applied after bending.

Several examples of illuminated automotive laminates can be found in the prior art, including: a waveguide layer, a light source, illumination means for directing light into the waveguide layer at an edge of the waveguide layer, and light diffusing means. These elements are included in all examples discussed subsequently, including some, but not all prior art.

In the prior art we also see the use of an array of LED lamps as a light source. The use of optical isolation layers for optical isolation and improving the light intensity of scattered light is also disclosed in some, but not all, cited examples of the prior art.

As previously described, total internal reflection occurs when the refractive indices between the two layers are significantly different. In a typical standard automotive laminate (two glass layers bonded to a PVB interlayer), light propagating approximately parallel to both major surfaces of the laminate will undergo total internal reflection at the air/glass interface, while little light is reflected at the glass/PVB interface. According to some published prior art documents, such as WO12028820a1, US20110267833a1, and according to fig. 1 of prior art document FR2989176B1, such a typical standard automotive laminate is used as a waveguide layer in its entirety. The main disadvantage of this approach is that, although the substrate is transparent, when light is reflected between the outer surfaces of the laminate, the defects in the substrate and the glass matrix absorb a certain percentage of the transmitted light.

By making the waveguide layer thinner, the path of light becomes shorter and absorption decreases. There are practical limits to how thin the laminate can be made. Rather than using the entire thickness of the laminate as a waveguide layer, the waveguide layer is optically isolated from the other layers of the laminate. This method of isolating the waveguide layer from the other laminate layers is disclosed in the prior art discussed below. In the cross-section of a standard automotive laminate, layers with a significant mismatch in refractive index are added, and the waveguide layers are optically isolated, thereby increasing the intensity of light directed into the passenger compartment by the light diffusing layer and reducing light escaping to the outside. The prior art shows two ways to achieve this.

The first method is to add a layer with a significantly lower refractive index than the waveguide layer. This layer acts as a light isolating layer trapping guided light within the waveguide layer. This can be achieved in several ways, for example by applying a coating on the inner surface of the main surface of the waveguide layer laminate. Another example is the use of a lower refractive index plastic interlayer or film. The literature has used PVB with a lower refractive index than the PVB used in typical automotive laminated glass.

The second approach is to use a waveguide layer with a higher index of refraction than the surrounding layers. The refractive index of Polycarbonate (PC) was 1.59. When laminated with a PVB interlayer (IR ═ 1.48), total internal reflection occurs, allowing the polycarbonate layer to act as a waveguiding layer.

WO2005/054915a1, "Light-Guiding Assembly and automatic Vehicle Roof" discloses a laminated Automotive Roof in which Light is coupled into additional plastic interlayers of the laminate along the edges and dispersed through Light scattering "centers" that may be located on various surfaces of the laminate. This document is an example of a second approach using a polycarbonate material with a refractive index much higher than that of the PVB bonding layer.

WO2007/077099a1, "Vehicle Glazing with Light-Guiding Assembly" discloses a laminate in which Light is scattered by microcracks in the glass or plastic layer. In one embodiment, a layer of polycarbonate plastic is used as the waveguide layer to take advantage of its higher index of refraction compared to a typical layer of glass, which is an example of the second approach. This application is also an example of the first method, as it also discloses embodiments using additional layers with a lower refractive index than the glass layer (waveguide layer) and the PVB layer.

EP2423173B1 "illuminated lighting structure with a porous layer" discloses a laminate in which a glass layer is used as the waveguide layer, light is coupled into the waveguide layer at the edges, the optical isolation layer described in the first method is provided by coating a porous coating on the waveguide layer, the coating having a refractive index at least 0.1 lower than the refractive index of the glass of the waveguide layer. Porous coatings are of the sol-gel type, where the pores are not the interstices of tightly packed nanobeads (e.g., silica beads).

US9612386B2, "lumines glazing unit with optical isolator" claims a laminated glass having a waveguide glass substrate layer, an optical isolation layer, a light source optically coupled to the glass substrate, and a light extraction device. The optical isolator includes a low index film made of a fluoropolymer material having an index of refraction that is at least 0.08 (5.4%) lower than that of the glass layer. This is another example of the first method of optically isolating the waveguide layer.

Standard laminated glass is used to provide interior lighting for passenger compartments, but often lacks lighting intensity and overall aesthetics. As shown in the methods disclosed in the prior art, strength and aesthetics can be improved by introducing a refractive index mismatch of at least 5% to optically isolate the waveguide layer. This requires the addition of improved/non-conventional layers on the laminate. However, it may not be practical and/or economical to produce such layers, and may also prove unsightly.

It should be noted that the prior art includes many abandoned applications and that, despite the above-mentioned disadvantages, the method of using the entire laminate stack as a waveguide layer is currently the best solution to achieve a balance between efficiency and complexity/cost.

It would be desirable to provide a lighting laminate that does not suffer from the disadvantages of the prior art, is not significantly more expensive to produce than standard laminates, and can be manufactured using standard automotive glazing equipment, materials and processes.

SUMMERY OF THE UTILITY MODEL

The disadvantages of the prior art, such as the low illumination intensity and aesthetic problems described above, are solved by a laminate comprising: waveguide layer, substantially dense SiO applied to one main surface of the interior of a laminate of waveguide layers₂A light isolating layer, at least one edge lighting device, and light scattering means for scattering light from the waveguide layer. The light scattering means is applied to the same inner surface of the waveguide layer as the light isolating coating. Resulting in a lighting laminate having excellent properties and which can be produced using standard automotive glazing equipment and processes. In the present application, SiO₂The refractive layer is prepared by MSVD or according to a modified sol-gel method that achieves a porosity of less than 22%.

Advantages of the invention

Higher contrast

Low investment

Higher illumination level

Capable of producing complex patterns

Without weakening the glass strength

Without increasing the probability of breakage

Lower haze

When the lighting device is switched off, the graphics are substantially invisible

The process adopts standard automobile glass equipment

The layer outside the optical barrier coating is optically isolated from the waveguide layer

Low degree of light leakage outside the vehicle

No special low-refractive-index PVB is required

Standard PVB can be used

Better coating adhesion to PVB and glass

Drawings

The features and advantages of the present application will become apparent from the following detailed description of the embodiments, taken in conjunction with the accompanying drawings, in which:

FIG. 1A shows a cross-section of a typical automotive laminated glass.

Figure 1B shows a cross section of a typical laminated glass with high performance films and coatings.

FIG. 1C shows a cross-section of a typical tempered monolithic automotive glass.

Figure 2 illustrates a two-layer lighting laminate according to an embodiment of the present application.

Fig. 3 illustrates a three-layer lighting laminate according to an embodiment of the present application.

Fig. 4A shows the lighting laminate in an OFF state.

Fig. 4B shows the lighting laminate in an Open (ON) state.

Reference numerals

2 glass layer

4 bonding/adhesive layer (interlayer)

6 mask/Black frit

8 thermally tempered glass

12 high performance film

14 optical barrier coating

18 high performance coating

20 light scattering device layer

22 waveguide layer

30 light bar

101 surface one

102 surface two

103 surface three

104 surface four

201 outer layer

202 inner layer

203 middle layer

Detailed Description

The following terminology is used to describe the laminated glass of the present application.

A typical automotive laminated glass cross-section is shown in fig. 1A and 1B. The laminate consists of two layers of glass, an outer layer of glass 201 and an inner layer of glass 202 firmly bonded together by a plastic layer 4 (interlayer). In the laminate, the glass surface of the vehicle exterior is referred to as surface one 101 or first surface. The opposite side of the outer glass layer 201 is the second surface 102 or second surface. The surface of the glass 2 in the vehicle interior is referred to as surface four 104 or fourth surface. The opposite side of the glass inner layer 202 is surface three 103 or a third surface. Surface two 102 and surface three 103 are bonded together by plastic layer 4. The screen 6 may also be coated on the glass. The mask is typically comprised of a black enamel frit printed on surface two 102 or surface four 104 or both. The laminate may have a coating 18 on one or more surfaces. The laminate may further comprise a film 12 laminated between at least two plastic layers 4.

The laminate may have more than two glass layers, which is very typical in bullet-proof glass. In this case, the additional glass layers and surfaces will be numbered in sequence. Thus, a third glass layer would be 203, having

surfaces

105 and 106.

Figure 1C shows a typical toughened automotive glass cross section. Tempered glass typically consists of a single ply of glass 201 that has been heat strengthened. This glass surface of the vehicle exterior is referred to as surface one 101 or first surface. The opposite side of the outer glass layer 201 is the second surface 102 or second surface. The second surface 102 made of tempered glass is located inside the vehicle. The screen 6 may also be coated on the glass. The mask is typically comprised of a black enamel frit printed on surface two 102. The glass may have a coating 18 on surface one 101 and/or surface two 102.

The term "glass" applies to many inorganic materials, including many opaque materials. In this specification we will refer to transparent glass only. From a scientific standpoint, glass is defined as a material state that comprises an amorphous solid that lacks the ordered molecular structure of a true solid. The glass has a crystalline mechanical stiffness and a liquid random structure.

Glasses are formed by mixing the various materials together and then heating to a temperature that causes them to melt and completely dissolve together, forming a miscible homogeneous fluid.

Most flat glass in the world was produced by the float glass process which was first commercialized in the 1950 s. In the float glass process, the raw materials are melted in a large refractory vessel and the molten glass is then extruded from the vessel into a molten tin bath in which the glass floats.

Types of glass that can be used include, but are not limited to, typical automotive glass ordinary soda lime glass as well as aluminosilicates, lithium aluminosilicates, borosilicates, glass ceramics, and various other inorganic solid-amorphous compositions that undergo glass transition and are classified as glasses, including those that are opaque. The glass layer may be composed of a heat absorbing glass composition as well as infrared reflective coatings and other types of coatings.

Most of the glass used for containers and windows is soda lime glass. Soda-lime glass is made from sodium carbonate (soda), lime (calcium carbonate), dolomite, silicon dioxide (silica), aluminum oxide (alumina) and small amounts of substances used to change color and other properties.

Generally, a laminate is an article consisting of a plurality of thin (with respect to their length and width) sheets, each sheet having two oppositely disposed major faces, typically of relatively uniform thickness, which sheets are firmly bonded to one another on at least one major face of each sheet.

As shown in fig. 1A and 1B, the laminated safety glass is manufactured by bonding two (201&202) annealed glasses 2 together with a plastic bonding layer comprising a transparent thermoplastic sheet 4 (interlayer).

Annealed glass is glass that is slowly cooled from the bending temperature through the glass transition range. This process eliminates any stress left by the glass during bending. The annealed glass was broken into large sharp-edged pieces. When the laminated glass is broken, the pieces of broken glass are held together by the plastic layer, as in a puzzle, helping to maintain the structural integrity of the glass. A vehicle with a damaged windshield may still be driven. The plastic layer 4 also helps to prevent objects from striking the laminate from the outside and causing punch through and improves occupant retention in the event of a car accident.

The glass layer may be annealed or strengthened. There are two methods that can be used to increase the strength of the glass. They are thermal strengthening (rapid cooling (quenching) of the hot glass) and chemical tempering (chemical tempering achieves the same effect by ion exchange chemical treatment).

Thermally strengthened all-tempered soda-lime-float glass having a compressive strength of at least 70 mpa may be used in all vehicle locations except for the windshield. Thermally strengthened (tempered) glass has a highly compressive layer on the outer surface of the glass, balanced by the tension in the glass which is created by the rapid cooling of the heat softened glass. When the tempered glass breaks, the tension and pressure are no longer balanced and the glass breaks into dull-edged beads. Tempered glass is much stronger than annealed laminated glass. The thickness of a typical automotive heat strengthening process is limited to the range of 3.2mm to 3.6 mm. This is due to the need for rapid heat transfer. With typical blast-type low pressure air quench systems, the high surface compression required for thinner glass is not possible.

A wide variety of coatings for improving the performance and properties of glass are available on the market and are in common use. These coatings include, but are not limited to, antireflective, infrared reflective, hydrophobic, hydrophilic, self-healing, self-cleaning, antimicrobial, scratch-resistant, graffiti-resistant, fingerprint-resistant, and anti-glare coatings.

Methods of application include Magnetron Sputtering Vacuum Deposition (MSVD) and other methods according to the prior art, which are applied by pyrolysis, spraying, Controlled Vapor Deposition (CVD), dip coating, sol-gel and other methods.

The glass layer is formed using gravity bending, pressure bending, cold bending, or any other conventional method familiar in the art. During gravity bending, the glass sheet is supported near the glass edges and then heated. The hot glass sags under gravity to form the desired shape. In the press bending process, a flat glass sheet is heated and then bent on a mold which fills a part of the surface. Air pressure and vacuum are commonly used to assist the bending process. Gravity bending and pressure bending methods of forming glass are well known in the art and will not be discussed in detail in this disclosure.

The main function of the plastic adhesive layer 4 (interlayer) is to adhere the main faces of adjacent layers to each other. The material of choice is typically a transparent thermoset.

For automobiles, the most commonly used plastic adhesive layer 4 (interlayer) is polyvinyl butyral (PVB). PVB has good adhesion to glass and optical clarity once laminated. It is produced by the reaction of polyvinyl alcohol and n-butyraldehyde. PVB is transparent and has high adhesion to glass. But PVB itself is too brittle. Plasticizers must be added to make the material flexible and to enable it to dissipate energy over the wide temperature range required for automobiles. Only small amounts of plasticizer are used. The plasticizer is typically a linear dicarboxylate. Two commonly used are di-n-hexyl adipate and tetraethylene glycol di-n-heptanoate. A typical automotive PVB interlayer comprises 30-40% by weight plasticizer.

In addition to polyvinyl butyral, an ionomeric polymer, Ethylene Vinyl Acetate (EVA), cast in place (CastInPlace, CIP) liquid resin, and Thermoplastic Polyurethane (TPU) can be used. Automotive interlayers are manufactured by an extrusion process that has thickness tolerances and process variations. Since a smooth surface tends to adhere to the glass, making it difficult to locate and trap air on the glass, the plastic surface is often embossed to create additional variation in the sheet in order to facilitate handling of the plastic sheet and removal of air (outgassing) from the laminate. Automotive PVB interlayers have standard thicknesses of 0.38 mm and 0.76 mm (15 and 30 mils).

The interlayer has an enhanced function in addition to bonding the glass layers together. The present application may include a sound damping interlayer. Such interlayers are composed wholly or partly of a softer and more flexible plastic layer than the plastic layers usually used. The interlayer may also be of a type having solar attenuation properties.

Various films can be found on the market that can be incorporated into laminates. Uses for these films include, but are not limited to, solar control, variable light transmission, increased stiffness, increased structural integrity, increased penetration resistance, increased occupant retention, providing a barrier, coloration, sun shading, color correction, and as functional and aesthetic graphic substrates. The term "film" shall include these as well as other products that may be developed or currently available to enhance the performance, function, aesthetics, or cost of the laminated glass. Most films are not adhesive. For incorporation into the laminate, a plastic sandwich is required on each side of the film to bond the film to the other layers of the laminate.

Automotive glass typically utilizes a heat absorbing glass composition to reduce the solar load of the vehicle. While heat absorbing windows are very effective, the glass will heat up and transfer energy to the vehicle cabin by convective heat transfer and radiation. A more efficient method is to reflect the heat back to the atmosphere, keeping the glass cooler. This is accomplished by using various infrared reflective films and coatings. Infrared coatings and films are generally too soft to be mounted or applied to the glass surface exposed to the component. Instead, they must be manufactured as an inner layer of the laminate product to prevent damage and degradation of the film or coating.

One advantage of laminated windows over tempered monolithic glass is that they can use infrared reflective coatings and films in addition to the heat absorbing composition and interlayer.

Infrared reflective coatings include, but are not limited to, various metal/dielectric layer coatings.

Infrared reflective films include both metal coated plastic substrates and organic non-metallic optical films that reflect in the infrared region. Most infrared reflective films consist of a plastic film substrate coated with an infrared reflective metal coating.

The present application is an illuminated laminate comprising at least two glass layers, at least one standard automotive plastic interlayer, a waveguide layer, illumination means, an optical barrier coating and light scattering means. The plastic interlayer is positioned between the two glass layers for firmly bonding the two glass layers together. At least one glass layer serves as a waveguide layer. Applying SiO to the inner surface of the laminate using MSVD or modified sol-gel processes₂The coating coats the waveguide layer. The coating has a refractive index substantially less than that of glass and acts as an optical barrier, trapping light within the waveguiding layer. The optical barrier coating may be applied to the entire surface or only to the portion containing the light scattering means. An illumination device is coupled to at least one edge of the waveguide layer.

The waveguide layer is preferably made of low iron, high visible light transmittance, ultra-transparent glass.

All major float glass suppliers produce ultra-clear glass. Ultratransparent glass does not have the green color characteristic of standard soda-lime glass. It is produced by removing natural iron from the batch. Ultra-transparent glass is widely used in furniture and solar panels. The use of an ultra-transparent material having a visible light transmittance of more than 90% as the waveguide layer can improve the brightness, contrast, and thus illumination efficiency of the laminate.

Other glass compositions may also be used for the waveguide layer with a correspondingly lower illumination level.

Light scattering can be accomplished by any conventional method of constructing a physical structure (decoupling method), such as ink printing, chemical etching, sandblasting, or other well-known techniques. Any internal light striking the interface between the scattering means and the surface of the waveguide layer is scattered rather than reflected, allowing a portion of the light to exit the surface. In the ON (ON) state, the diffuser provides a high level of illumination. Under normal lighting conditions, the graphics are virtually invisible when the light source is in an OFF state. Another benefit is that there is no loss of strength or degradation of optical performance.

In some examples of the prior art, a slightly lower index of refraction of the plastic interlayer relative to glass is considered sufficient to provide sufficient internal reflection. For a conventional PVB interlayer, regardless of which layer is optically coupled to, the entire thickness of the laminate will tend to act as a waveguide layer unless an optical isolation layer is used. In fact, the internal reflection is very poor, resulting in low illuminance and low contrast, which must be compensated by increasing the intensity of the illumination means. To achieve total internal reflection, some disclosures of the prior art require the use of an optical isolation layer having a refractive index that is at least 0.1 less than the refractive index of glass.

Recognizing this fact, the laminate of the present application has SiO applied to the inner surface of the waveguide layer for the purpose of further improving and achieving total internal reflection₂An optical barrier coating. SiO can be applied by a variety of methods₂And (4) coating. The quality and physical properties of the coating depend on the process and use, the process parameters, and the materials used as process inputs and may vary greatly from one aspect to another.

Some embodiments of the prior art have adopted this approach. One example describes coating a sol-gel porous silica coating.

Sol-gel coatings are not common in the automotive glass industry. On the other hand, MSVD coating equipment is widely used to produce solar control coatings. Furthermore, the processing time of sol-gel coatings is much longer than that of modern mass-production MSVD coaters. Inline mass MSVD coaters are very common in automotive glass plants.

Typical sol-gel processes produce coatings that tend to be rough and non-uniform, resulting in unwanted light scattering, low adhesion to plastic interlayers and glass, and high visibility of the coating. Furthermore, such coatings are not as durable as MSVD coatings and are therefore more susceptible to damage during processing.

Dense and continuous SiO produced by vacuum sputter deposition process coating in this application₂The results of the optical barrier coating are far superior to the porous SiO of the prior art₂Sol-gel coatings and processes. In most embodiments, the dense optical barrier coating has a refractive index of about 1.45 and a thickness that can range from 50nm to 200 nm.

The MSVD coated optical barrier coating can be applied to the slab waveguide glass layer for in-line continuous processing either before or after the light scattering device is applied/fabricated on the inner surface. The waveguide glass layer can then be directly subjected to a bending process.

The MSVD optical barrier coating is very smooth and uniform over the entire coating area. The coating is very flat and durable. The chemical composition of the coating is also very uniform in the coating area. Adhesion to both glass and plastic interlayers was good.

Alternatively, in some other embodiments of the present application, refractive SiO₂Optical barrier coatings are applied by modified sol-gel formulations and processes. The improved coatings are prepared using standard formulations, e.g., using Tetraethylorthosilicate (TEOS) precursors, various alcohols as solvents, and are acidic (e.g., HCl) or basic (e.g., NH)₃ H₂O) reagent as a catalyst to provide a low porosity film. It uses a movable and controllable spray head to spray the solution onto the glass after it has been heated and bentOn glass, such coatings are uniform and dense, and the porosity level of the coating is lower, when coated, than coatings produced by processes described in the prior art. This alternative method is advantageous when the lighting glass is produced in a factory without an MSVD coater or in a factory with limited production despite an MSVD coater. Compared with the MSVD coating machine, the spraying process can be implemented in-line, does not produce a bottleneck, and has relatively less investment and relatively smaller floor area.

The improved sol-gel optical barrier coating has several advantages over the prior art. According to the prior art (document EP2423173B 1), the coating is applied while the glass is flat and then heated to a temperature exceeding at least 450 ℃, preferably exceeding 600 ℃, in order to cure the coating. The improved optical barrier coating is heat treated at a temperature of 200-500 ℃ for 10 to 60 minutes and may be applied to glass by a spray process after bending. The improved sol-gel optical barrier coating has a porosity (volume percent of pores in the coating) of less than 22%, and may even be less than 11%. Although not as dense as the MSVD optical barrier coating, this porosity is lower than the prior art porosity, which is greater than 22% and can exceed 78%. The coating refractive index can be estimated using the first approximation equation described in the prior art:

n_{porous coating}＝fn_atr+(1-f)n_{dense coating}

wherein n is_{porous coating}Is the refractive index of the porous coating, n_{dense_coating}Is SiO₂Refractive index of dense coating, n_airIs the refractive index of air and f is the volume fraction of pores. The refractive index of the modified sol-gel coating was calculated to be in the range of 1.35 to 1.45. In some preferred embodiments, the refractive index is in the range of 1.351.40. The improved coating is also more durable than prior art coatings due to its higher density. The higher density and lower porosity also improves the adhesion of the coating to the laminated glass and plastic interlayer. The thickness of the coating does not have to be as thick as the prior art porous coatings. The thickness may be in the range of 50nm to 1 μm, but is preferably in the range of 100nm to 500nm or even 100nm to 200 nm.

By applying an optical isolation layer over the waveguide layer, total internal reflection is achieved. Little, if any, light escapes into the edges of the plastic interlayer and other layers opposite the waveguide layer, which are effectively optically scattered.

The main steps of the glass manufacturing method according to the application of the MSVD optical barrier coating comprise:

1. providing a glass substrate, and forming a glass substrate,

2. the light scattering device is coated/fabricated onto a glass substrate,

3. the MSVD optical barrier coating was applied to the light scattering device side of the glass,

4. bending a glass substrate with a light-scattering device and an optical barrier coating, and

5. the glass substrate with the light scattering device and the optical barrier coating is laminated with at least one further glass layer.

In the case where a sol-gel optical barrier coating is used instead of a MSVD coating, the order of these steps may be changed. The method mainly comprises the following steps:

1. providing a glass substrate, and forming a glass substrate,

2. the light scattering device is coated/fabricated onto a glass substrate,

3. bending a glass substrate with a curved light-scattering device, and

4. a sol-gel optical barrier coating is coated and cured on the light scattering device side of the glass substrate,

It must be understood that the above-described manufacturing process steps applicable to MSVD and sol-gel optical barrier coatings are not limited to the above-described sequence. It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the sequence of steps of a method known in the art without departing from the spirit of the application. Either method may also provide a glass substrate having a light scattering device and an optical barrier coating, the glass substrate being finally laminated with at least one further glass layer such that the light scattering device and optical barrier coating are disposed on an inner surface of the laminate. In some embodiments, a waveguide layer having a light scattering device and an optical barrier coating is disposed on the laminated glass stack location, rather than the interior of the automobile.

Examples of various embodiments of the method to produce a product are shown in the accompanying drawings.

It is noted that for the hexagonal patterns shown in fig. 2 and 3, the interior of the hexagons may have the scattering means (as shown), or the spaces between the hexagons may have the scattering means.

The light scattering means must be located on one of the interior surfaces of the laminate. That is, one of the surfaces in contact with an adhesive layer (e.g., PVB). Other interlayer materials may be used without departing from the intent of the present application. As is well known (e.g. as taught in patent application WO2005/054915a 1), the material of the interlayer is preferably chosen such that the refractive index of the interlayer is substantially the same as the refractive index of the glass sheet. Because the refractive index of the interlayer material is very close to that of glass, light coupled into the waveguide layer is not reflected at the glass/interlayer interface. The material of the interlayer, such as (PVB) and EVA, has a refractive index of about 1.48, which is considered to be about the same as the refractive index of the glass sheet.

To reduce ghosting and the amount of light visible from outside the vehicle, the PVB layer should have a visible light transmission of no greater than 40%. The outer glass layer, which combines the interlayer and the waveguide layer, should have a visible light transmission of not more than 20%, preferably less than 20%.

To improve the uniformity of the illumination, the illumination means are arranged along opposite sides. They may be the front and back or the left and right sides of the laminate. In an embodiment, a "light bar" is used as a lighting device. Each light bar is comprised of LED chips coupled in series with a microlens array for focusing light at the edge of the waveguide layer. It has been found that a bright light intensity of at least 1000cd/m is required to achieve a similar intensity as conventional cabin roof lighting²Within the range of (1).

The efficiency and intensity of the emitted light can be further enhanced by applying a light reflective coating to at least a portion of the glass edge not used for the light bar. Several coatings with high reflectivity are known. In addition, a thin film may also be applied at or near the edge to act as a reflector. Highly reflective films have been developed and are commonly used in liquid crystal displays and televisions to improve the uniformity and intensity of the backlight of the liquid crystal cell.

It should be noted that other lighting devices may be used instead of the LEDs in the embodiments described without departing from the concept of the present application. Any device that meets the strength and packaging requirements can be used, including OLEDs, electroluminescence, optical fibers, light pipes, and even devices not yet invented.

The light bar is bonded to the edge using an optical adhesive. Optionally, the edges of the waveguide layer may be polished to increase visible light transmission. The edge may also be ground to a convex, concave or other contour to help focus light inside the edge.

Since the LED chip acts as a point source, the distance between the glass edge and the chip should be at least 0.5 mm. The actual spacing will depend on many factors including, but not limited to, waveguide layer edge processing, chip size, chip strength, light bar lenses, and light bar diffusers (if provided).

In the OFF (OFF) state, haze is below 6% and visible transmission is reduced below 10% using a light scattering device. Under normal viewing conditions, the ink graphics are virtually invisible.

Examples

1. Example 1 shown in fig. 2 is a laminate having three glass layers. It consists of a 3.6mm full tempered solar green soda-lime glass outer layer 201, on the second surface of which is printed a black enamel frit 6. The outer glass layer 201 was bonded with an intermediate glass layer 203 consisting of 2.2mm clear soda lime glass using grey PVB4 with a visible light transmission of 40%. The intermediate layer 203 is bonded to the 2.1mm low-iron soda-lime glass inner glass layer 202, that is to say the waveguide layer 22, which has a visible light transmission of 92%. Coating the interior surface of the laminate 105 with MSVD SiO₂The coating acts as an optical isolation layer 14. Applying the hexagonal light-scattering device layer 20 to a fifth layer of the laminate using ink on the surface of the waveguide layer 22On the surface 105. The ink was printed on the flat glass prior to coating and bending. The lithographic glass is then heated to cure the ink. The waveguide layer 22 also has a black enamel frit band 6 printed on the fourth surface. Light bars 30 each including 10 LED chips were adhered to the left and right edges of the laminate. The edges of the waveguide layer 22 are ground to a convex profile and polished to facilitate light entry from the light bar 30. The intensity of the light bar 30 is more than 1000cd/m²And is also provided with a micro lens array (not shown) to direct and focus the light. The laminate can be illuminated in a variety of colors using RGB LEDs. The total visible transmission of the laminate was 20%. The autoclave cycle (autoclave cycle) is extended to allow PVB4 to flow into the micro-defect. When the light bar 30 is in an OFF state, the processing area is substantially invisible.

2. Example 2 shown in figure 3 consists of a 2.1mm annealed solar green soda lime glass outer layer 201 with a black enamel frit 6 printed on the second surface. The outer glass layer 201 is bonded to the inner glass layer 202 using grey PVB4 having a visible light transmission of 40%, the inner glass layer 202 being a 2.1mm low-iron soda-lime glass waveguide layer 22 having a visible light transmission of 92%. Coating the third surface 103 with MSVD SiO₂The coating acts as an optical isolation layer 14. The hexagonal light scattering device layer 20 is applied to the major surface of the waveguide layer 22 facing the interior of the laminate and cured as described in example 1.

The waveguide layer 22 also has a black enamel frit band 6 printed on the fourth surface. Light bars 30 each including 10 LED chips were adhered to the left and right edges of the laminate. The edge of the waveguide layer 22 is ground to a convex profile and polished to facilitate light entry from the light bar. The intensity of the light bar 30 is more than 1000cd/m²And is also provided with a micro lens array (not shown) to direct and focus the light. The laminate can be illuminated in a variety of colors using RGB LEDs. The total visible transmission of the laminate was 20%.

3. Embodiment 3 is the same as embodiment 1 and further includes a mirror coating (not shown) deposited on the second surface 102 of the outer glass layer 201 to enhance light output.

4. Embodiment 4 is the same as embodiment 2 and further comprises a mirror coating (not shown) deposited on the second surface 102 of the outer glass layer 201 to enhance light output.

5. Embodiment 5 is the same as embodiment 1 and further includes a mirror coating (not shown) deposited on the edges not coupled to the light bars of the waveguide layer 22 to enhance light output.

6. Example 6 is the same as example 1, but the optical barrier coating and light scattering device layer are applied to only 10% of the surface area of the waveguide layer.

7. Example 7 is the same as example 1, but SiO₂The optical barrier coating is applied using a modified sol-gel process and the coating is applied to the glass layer after the glass layer is bent.

8. Example 8 the same as example 2, but with the addition of a light scattering device coated on the outer glass layer surface and an additional SiO₂An optical barrier coating, the surface being internal to the laminate in order to create individual lighting features or patterns on opposite sides of the laminate. The further illumination device is configured to project light into the outer glass layer.

9. Example 9 is the same as example 8, but with the addition of a variable light transmission layer (not shown) selected from SPD, LC and PDLC layers, said layer being arranged on SiO₂Between the optical barrier coatings, the purpose is to isolate the illumination features on each side of the laminate. When the variably light transmitting layer is in an opaque state, the illumination characteristics of each side of the laminate act independently without interfering with each other. On the other hand, when the variably light transmitting layer is in a non-opaque state, the illumination characteristics on both sides of the laminate may be coordinated.

Claims

1. An illuminated laminated glass comprising:

at least two glass layers (201, 202, 203): a first glass layer and a second glass layer, wherein the first glass layer acts as a waveguide layer (22);

at least one interlayer (4) between the layers of laminated glass and for bonding the layers of laminated glass;

an illumination device (30) projecting light into the waveguide layer (22) from at least a portion of at least one end face;

-light scattering means (20) applied on the surface of said waveguide layer (22); and

SiO₂an optical isolation coating (14) at least partially in direct contact with the waveguide layer (22);

wherein the SiO₂An optical barrier coating (14) is located between the at least two glass layers (201, 202, 203);

wherein the SiO₂The optical isolation coating (14) has a porosity of less than 11%; and

wherein the SiO is₂The refractive index of the optical isolation coating (14) is less than 0.1 lower than the refractive index of the waveguide layer (22).

2. The laminated glass according to claim 1, wherein the total visible light transmission of the at least one interlayer (4) is 40% or less.

3. The laminated glass according to claim 1, wherein the waveguide layer (22) has a total visible light transmittance of at least 90%.

4. The laminated glass according to claim 1, wherein one of the at least two glass layers (201, 202, 203) other than the waveguide layer (22) is selected such that: such that the total visible light transmission of the laminated glass is no greater than 20%, or no greater than 10%.

5. The laminated glass according to claim 1, wherein the light scattering means (20) comprises at least one graphic.

6. The laminated glass of claim 1, wherein the SiO is₂The optical barrier coating (14) is vacuum sputtered SiO₂An optical barrier coating.

7. According to claim 1 to 5The laminated glass according to any one of the preceding claims, wherein the SiO is₂The optical barrier coating (14) is sol-gel SiO₂And (4) coating.

8. The laminated glass of claim 7, wherein the SiO is₂The optical barrier coating (14) is applied after bending using a spray coating process.

9. The laminated glass of claim 7, wherein the SiO is₂The optical barrier coating (14) is heat treated at a temperature of less than 450 ℃.

10. The laminated glass according to claim 7, wherein the SiO is₂The optical barrier coating (14) has a thickness in the range of 50nm to 1 μm.

11. The laminated glass of claim 7, wherein the SiO is₂The optical barrier coating (14) has a thickness in the range of 100nm to 500 nm.

12. The laminated glass of claim 7, wherein the SiO is₂The optical barrier coating (14) has a thickness in the range of 100nm to 200 nm.

13. The laminated glass of claim 6, wherein the SiO is₂The optical barrier coating (14) is a dense continuous coating.

14. The laminated glass of claim 6, wherein the SiO is₂The optical barrier coating (14) has a thickness in the range of 50nm to 200 nm.

15. The laminated glass according to claim 1, wherein at least one end face of the laminated glass is coated with SiO₂An optical barrier coating (14).

16. The laminated glass of claim 1, wherein the SiO is₂The refractive index of the optical isolation coating (14) is 5% or more lower than the refractive index of the waveguide layer (22).

17. The laminated glass of claim 1, wherein the second glass layer serves as a second waveguide layer; wherein said light scattering means is further applied to the surface of said second waveguide layer; wherein the laminated glass further comprises a second SiO at least partially in direct contact with the second waveguide layer₂An optical barrier coating; wherein the second SiO₂An optical barrier coating is positioned between the at least two glass layers.

18. The laminated glass of claim 17, wherein the illumination device is configured to project light into the second waveguide layer.

19. The laminated glass of claim 18, further comprising a variable light transmission layer selected from SPD, LC, and PDLC layers; wherein the variable light transmission layer is located on the SiO₂Between the optical barrier coatings.

20. The laminated glass according to claim 1, wherein the at least two glass layers (201, 202, 203) are two glass layers (201, 202), and wherein the first glass layer is an inner glass layer (202) and the second glass layer is an outer glass layer (201).

21. The laminated glass according to claim 20, wherein the light scattering means (20) is applied on a surface of the waveguide layer (22) facing the interior of the laminated glass.