WO2019186507A1

WO2019186507A1 - Roller free intelligent automotive roof glazing

Info

Publication number: WO2019186507A1
Application number: PCT/IB2019/052633
Authority: WO
Inventors: Mario Arturo MANNHEIM ASTETE; Andres Fernando SARMIENTO SANTOS; Laura Granados Caro; Merlyn ROJAS VALLE
Original assignee: AGP America SA
Current assignee: AGP America SA
Priority date: 2018-03-29
Filing date: 2019-03-29
Publication date: 2019-10-03
Anticipated expiration: 2020-09-29

Abstract

The present invention discloses an automotive switchable glazing that changes the visible and near infrared light transmittance properties of the glazing with passive materials. Opposite to expensive technology such as active switchable materials, the 5 level of darkness of the thermochromic materials of the present invention can be dynamically controlled by means of including thermochromic materials placed in contact with any of the interior surfaces of the outer or the inner glass layers, in combination with a plastic layer placed in contact with any of the interior surfaces of the outer or the inner glass layers. The visible light transmittance of the automotive 10 switchable glazing of the present invention ranges from 0.1% to 10% in the visible spectrum. Likewise, the near infrared light transmittance is between 20% to 80% in the near infrared spectrum.

Description

ROLLER FREE INTELLIGENT AUTOMOTIVE ROOF GLAZING

Field of the invention

The present invention relates to the field of laminated automotive glazing including light control materials.

Background of the invention

Vehicle manufacturers have increasingly become more interested in drastically reducing costs and providing alternative solutions to resolve different customer concerns. One of those concerns is to control the level of light transmission to the interior of the vehicle, either by using passive or active solutions. One way to control such level consists on passive technology over the sunroofs, which up to date have been solved by incorporating mechanical means such as mechanical shades (roller shades) in order to block the sunlight under certain climate conditions. However, mechanical shades are complex to implement, heavy, extremely costly and compromise the passenger’s comfort as well as the visibility to the outside.

Market indicates that there is a desire for improved vision and an increased level of natural light in the passenger compartment that a panoramic glass roof would provide. Styling trends for many years now have favored larger glazed areas on vehicles which has the added benefit in that it also reduces weight. While the purpose of the transparent roof panel is to allow light to enter the vehicle, it has been a purpose that under some circumstances it may be desirable to limit the amount of light entering the vehicle. On a bright sunny day, the intensity of the light can become uncomfortable to the skin and eyes. The solar radiation entering through the roof panel also can rapidly heat the interior of the vehicle increasing the load on the air-conditioning system and increasing the interior temperature of a parked vehicle by several degrees. As a result, different levels of darkness on the glass are suitable. Recently, car manufacturers (OEMs) have been interested in looking for new technologies for light controlling instead of using expensive roller devices and have included new functional characteristics into the glass windows such as switchable technology. As will be explained in detail, switchable technology can change the optical and thermal properties in response to climate, either temperature or light transmittance or even to the user preferences and requirements. New light controlling methods include active and passive technologies capable of controlling light transmittance and solar heat transmittance: such as electrochromic, photochromic, thermochromic, Polymer Dispersed Liquid Crystal (PDLC), Suspended Particle Devices (SPD) and electric field sensitive films. Additional films include but are not limited to: solar control, visible light transmission, increased stiffness, increased structural integrity, improved penetration resistance, improved occupant retention, providing a barrier, tint, providing a sunshade, color correction, and as a substrate for functional and aesthetic graphics. The term“film” shall include these as well as other products that may be developed or which are currently available which enhance the performance, function, aesthetics or cost of a laminated glazing. Nowadays, most of the sun roofs in passenger vehicles have a tempered or laminated glass with a VLT of 20%. These also have a mechanical shade underneath. However, as stated before, those mechanical shades are expensive, heavy and compromise the passenger’s head room, comfort as well as the visibility to the outside. Some OEMs are starting to introduce vehicles with panoramic glass roofs without a mechanical shade. These laminates are passive thus having just one fixed visible light transmission level (VLT). These are still a very limited number of car makers that are concerned about passenger comfort. The most conservative OEMs are specifying a 1.5% VLT (darker roof) and others up to 6% VLT (lighter roof). Concern is that in some different climate conditions, the product itself will limit the external visibility. Another worry of OEMs is that materials that allow higher clarity, the product won’t block enough amount of light rays, which is commonly known as glare. Therefore, there is a need for OEMs to provide a higher level of comfort and provide a higher control over the light transmittance using materials at low costs.

The most common technology to control the light inside a car is to use sunroofs with electrically switchable materials on which the tint can be dynamically controlled. However, it can only operate over a limited range of temperature and light variation. The time that it takes to switch from light to dark and back is dependent upon temperature and light transmittance. Extremes of temperature adversely affect the time that it takes to change state. In addition, exposure to high temperatures and light illuminance, for an extended period will shorten the life of the glazing.

This technology of using sunroofs with electrically switchable light transmission is successful in certain niche technologies, but it can be 10 to 50 times more expensive than a passive technology, forcing the use of such technology to almost exclusively for privacy glass.

Electrochromic switchable glazing undergoes a chemical reaction when a current is passed through the active material, in much the same way that a battery functions when it charges and discharges. The active material undergoes an oxidation or reduction reaction as the materials changes from light to dark and back.

SPD is a variable tint technology with which the level of tint can be controlled and varied in response to an applied electrical field. SPD goes from dark in the off state to less dark in the on state. In a SPD film, microscopic droplets of liquid containing needle like particles, light vales, are suspended in a matrix. In the off state the particles are in a random state of alignment and block the transmission of light. The degree of alignment and resulting tint can be varied in response to the applied voltage. The light transmittance in the on and off states can also be shifted through changes to the thickness and composition of the active material. In the off state, it is still possible to see clearly through SPD.

SPD glazing is produced by adding a special film to a laminate. The typical construction of the film is comprised of the active material sandwiched between two thin plastic interlayers having a transparent conductive coating on each. The film is laminated in between two plastic interlayers to form a laminated glazing. PDLC is a light scattering technology which goes from opaque in the off state to clear in the on state. In a PDLC film, microscopic droplets of liquid crystal are suspended in a polymer matrix. In the off state the liquid crystals are in a random state of alignment and scatter the light providing privacy. In the off state, the film is substantially opaque. When an electric filed is applied, the crystals align and allow light to pass. The degree of scattering can be varied by varying the amplitude of the applied voltage. The level of light transmittance in the on and off states can also be shifted by making changes to the thickness and composition of the active material. PDLC is primarily a privacy product though it can also be used for solar control as it reduces the solar energy transmitted.

SPD and PDLC however operate on a different principle. There is no chemical reaction. The molecules that make up the active material undergo a kinetic change in response to the presence of an electrical field. Therefore, the switching time of SPD and PDLC is orders of magnitude faster than electro-chromic glazing.

Hence, there is the need to bide and research of new materials with the aim to lower the cost of production of laminated glazing with a lower price, fewer control systems that increase the costs of the glazing and providing a high acceptable level of functionality and a visible light transmittance of at least in the range of 0.6% to 6%.

Brief description of the invention

The present invention discloses a roller free intelligent dynamic automotive roof glazing comprising a plurality of glass layers, an intermediate layer composed of a combination of different materials such as a thermochromic material and plastics materials wherein the thermochromic material is of variable transmissivity which is determined by either the temperature of the thermochromic material or the incident solar light radiation such that a change in said temperature or light radiation results in a change in the visible and near infrared light transmittance of the thermochromic material. The glazing of the present invention is able to change the visible and near infrared light transmittance on a sunny/hot day being able to darken down to 1.5% and much less to 0.6% VLT and also increase the VLT on a cloudy/cold day or with the vehicle in movement to 6% VLT. The present invention maximizes the experience of having a transparent sunroof at a much lower cost than the current solutions available in the prior art as there is no need to incorporate a mechanical shade (roller). The near infrared light thermochromic material is designed to be transparent above 250 nm, allowing UV light to be absorbed by the visible light thermochromic.

Brief description of drawings

These features and advantages of the present invention will become apparent from the detailed description of the following embodiments in conjunction with the accompanying drawings, wherein:

Figure 1 illustrates the cross section of a laminate of the prior art.

Figure 2A illustrates a cross section of an automotive laminate according to an embodiment of the present invention.

Figure 2B illustrates a cross section of an automotive laminate with coating and performance film according to an embodiment of the present invention.

Figures 3A illustrates a cross section of an automotive laminate according to an embodiment of the present invention.

Figures 3B illustrates a cross section of an automotive laminate according to an embodiment of the present invention.

Figure 4A illustrates a cross section of an automotive laminate according to an embodiment of the present invention.

Figure 4B illustrates a cross section of an automotive laminate according to an embodiment of the present invention.

Reference numerals

2 Glass

4 Plastic Interlayer

6 Thermochromic interlayer

11 Obscuration band

18 Coating

42 Metallic coating/ metallic film 43 Low-e coating /low-e layers

50 Bus bars

101 Surface one

102 Surface two

103 Surface three

104 Surface four

201 Outer glass layer

202 Inner glass layer Detailed description of the invention

While the purpose of the transparent roof panel is to allow light to enter the vehicle, it is possible that, under some circumstances, it may be desirable to limit the amount of light entering the vehicle. On a bright sunny day, the intensity of the light can become uncomfortable to the skin and eyes. The solar radiation entering through the roof panel also can rapidly heat the interior of the vehicle increasing the load on the air- conditioning system and increasing the interior temperature of a parked vehicle by several degrees. As a result, dark tinted glass, with an approximate light transmittance of 20%, is typically used. The present invention discloses a passive way for controlling the change in the temperature or light transmittance of the thermochromic material reducing the solar radiation spectrum by attenuating the solar light transmittance when it is hot and transmitting the solar light when it is cold or when the solar radiation is low. The present invention improves the reaction of the materials by employing a special stack of laminated materials that enhance the light intensity modulation and shorten reaction time of the thermochromic materials.

The combination of thermochromic materials, plastic materials and glass layers optimizes the absorption of light transmittance when exposed to solar light in the UV, visible and near infrared (NIR) region. The combination of these materials takes advantage of the property at certain times of the day to change their light properties. Typically, the thermochromic effect occurs over a range of temperatures or a change in the intensity of solar radiation and it is observed as a gradual color change. This change can be reversible. The temperature in which the thermochromic material transition from one state (v.gr. clear) to another (v.gr. dark) is typically maximized between 25° C and 70° C. Likewise, the range of wavelength spectrum of a thermochromic material changes depending on the intensity of light, which in typical available thermochromic materials, the power of solar radiation typically ranges between 400 W/m2 up to 1,000 W/m2. These thermochromic materials being formed from but not limited to vanadium oxides (such as V0₂ or V₂O5), titanium oxides (such as Ti₂0₃), iron oxides (such as FC₃0₄) and molybdenum oxides (such as Mq9q₂6). The thermochromic material can be implemented in the present invention as a film, coating, layer or any suitable means for implementing the thermochromic material in a laminated glass that permits the absorption of light at different wavelengths. The coating may be applied in surface two 102 of the outer glass layer by using any vacuum sputtering technique (v.gr. Magnetron Sputtered Vacuum Deposition MSVD) directly onto the glass and is comprised of multiple layers of metal and dielectrics.

A dark color with a high absorptivity rate would be recommended. In this way, when the laminate is in the heat or light absorbing phase, it is gaining as quickly and as much heat as possible or light as much as possible. Dark colors with different tints may also be used with the laminate for aesthetic considerations but will change the performance of the laminate since it could reduce the absorptivity rate.

A typical automotive laminate is shown in Figure 1, comprised of two glass layers 2, the exterior or outer glass layer 201 and interior or inner glass layer 202 that are permanently bonded together by a plastic interlayer 4. The exterior glass surface that is on the outer glass layer 201 is referred to as surface one 101 or the number one surface. The opposite face of the same glass layer is surface two 102 or the number two surface. The interior glass surface that is on the inner glass layer 202 is referred to as surface three 103 or the number three surface. The opposite face of same glass layer is surface four 104 or the number four surface. Surfaces two 102 and three 103 are bonded together by the plastic interlayer 4. The thermochromic materials of the present invention can be of different geometries, for instance, it can be cut to the geometry of complex shapes of glasses and can also have different colors depending on the glass application. The glass layers are formed using gravity bending, press bending, cold bending or any other conventional means known in the art. Gravity and press bending methods for forming glass are well known in the art and will not be discussed in the present disclosure. The laminate of the present invention may have different reflective or anti-reflective interlayers or coatings 18 in order to filter different type of wavelength. For instance, in some embodiments such interlayers or coatings can filter infrared and can be applied over surface one 101 or surface two 102 of the glass layer 201. Infrared reflecting films include both metallic coated substrates as well as organic based optical films which reflect in the infrared. Lamination of films requires additional plastic interlayer to bond the opposite faces of the film to the opposite faces of the glass layers.

Additional embodiments of the present invention may include antireflective coatings applied over surface four 104 of the glass layers. These anti -reflective materials help regulate the temperature of the thermochromic material by reflecting the energy absorbed. The heat energy in the thermochromic layer is transferred from the layer to the surroundings by conduction, convection or radiation, regulating the temperature of the thermochromic material. It should be noted that the types of glass that may be used for the present invention include but are not limited to the common soda-lime variety typical of automotive glazing as well as aluminosilicate, lithium aluminosilicate, borosilicate, glass ceramics, and the various other inorganic solid amorphous compositions which undergo a glass transition and are classified as glass included those that are not transparent. Additional embodiments of the invention include, but are not limited to soda-lime glass clear, green, solar green, grey, blue or brown color. The glass layers of the present invention may be annealed or strengthened. There are two processes that can be used to increase the strength of glass. In the chemical tempering process, ions in and near the outside surface of the glass are exchanged with ions that are larger. This place the outer layer of glass in compression. Compressive strengths of up to 1, 000 MPa are possible. Glass layers can range from 2.0 mm to 4 mm for any of the outer or inner layers.

Fully heat tempered glass has a layer of high compression on the outside surfaces of the glass, balanced by tension on the inside of the glass which is produced by the rapid cooling of the hot softened glass. When tempered glass breaks, the tension and compression are no longer in balance and the glass breaks into small beads with dull edges. Tempered glass is much stronger than annealed laminated glass. The thickness limits of the typical automotive heat tempering process are in the 3.0mm to 3.15 mm range. This is due to the rapid heat transfer that is required. It is not possible to achieve the high surface compression needed with thinner glass using the typical blower type low pressure air quenching systems. The compressive strength of a fully heat tempered soda lime glass is in the range of 150-200 MPa while the compressive strength of a heat strengthened (semi-tempered) soda lime glass is in the range of 70-100 MPa. The thickness limits of the typical automotive heat strengthened (semi-tempered) soda lime glass are in the l.4mm to 1.6 mm range.

The laminated glass of the present invention can be made by bonding two sheets of glass, the outer glass layer 201 and the inner glass layer 202 of annealed glass 2 together using a plastic bonding layer comprised of a thin sheet of dark plastic or thermoplastic interlayer 4 as shown in Figures 2A and 2B. Annealed glass is a glass that has been slowly cooled from the bending temperature down through the glass transition range. This process relieves any stress left in the glass from the bending process. Annealed glass breaks into large shards with sharp edges. When laminated glass breaks, the shards of broken glass are held together, much like the pieces of a jigsaw puzzle, by the plastic interlayer helping to maintain the structural integrity of the glass. A vehicle with a broken windshield can still be operated. The plastic interlayer 4 also helps to prevent penetration by objects striking the laminate from the exterior and in the event of a crash occupant retention is improved.

The plastic interlayer 4 has the primary function of bonding the major faces of adjacent layers to each other. The material selected of the prior art is typically a clear plastic, however, the present invention comprises dark plastic interlayers. For automotive use, the most commonly used plastic interlayer 4 is polyvinyl butyl (PVB). In addition to polyvinyl butyl, ionoplast polymers, ethylene vinyl acetate (EVA), cast in place (CIP) fluid resin and thermoplastic polyurethane (TPU) can also be used. Interlayers are available with enhanced capabilities beyond bonding the glass layers together. In different embodiments, the glass laminate of the present invention may include interlayers designed to dampen sound or include ionoplastic materials. Such interlayers are comprised whole or in part of a layer of plastic that is softer and more flexible than that normally used. Additional embodiments of the present invention include a plastic interlayer made of dark PVB. Dark PVB interlayers may have different levels of obscuration and can be of different thicknesses. Typical PVB thicknesses ranges 0.2 mm to 0.9 mm. In additional embodiments, the PVB plastic interlayer is comprised of particles that absorb partially the infrared heat of the sun. The interlayer may also be of a type which has solar attenuating properties. Automotive interlayers are made by an extrusion process that has a thickness tolerance and process variation. As a smooth surface tends to stick to the glass, making it difficult to position on the glass and to trap air, to facilitate the handling of the plastic sheet and the removal of air (deairing) from the laminate, the surface of the plastic is normally embossed contributing additional variation to the sheet. Standard thicknesses for automotive PVB interlayer at 0.38 mm and 0.76 mm. The interlayer may be an opaque thermoplastic to radiation wavelengths, for instance, opaque to radiation wavelengths having a VLT of 20% to 60%. Different VLT ranges may also be applied. Figures 2A and 2B show different embodiments of the present invention, where in addition to the dark plastic interlayer 4, a thermochromic interlayer 6 is placed between the laminate. Figure 2A shows an embodiment comprised of two glass layers 2, an exterior glass layer 201 and interior glass layer 202. A thermochromic interlayer 6 faces the surface two 102 and is bonded to the inner glass layer 202 by a plastic interlayer 4. Figure 2B shows another embodiment of the invention showing a laminated glass with an obscuration band 11 that may be also applied to any surface of any of the inner or outer glass layers. Obscuration bands 11 are commonly comprised of black enamel frit printed on the surface two 102 or in the surface four 104 or on both. The glass laminate of the present invention may also comprise a coating 18 on any of the surfaces one 101, two 102, three 103 or four 104. The embodiment of Figure 2B comprises a coating 18 on surface four 104.

Figure 3A shows another embodiment of the invention showing a laminated glass as described above, but in this case the coating 18 is applied on surface two 102.

Additional embodiments of the invention may incorporate low-e coatings 43 or low-e layers on any of the surfaces of the glass layers in order to provide a heat barrier and increase the life for the overheating of the materials included in the laminate. The low-e coatings or layers avoid the performance degradation of the laminated materials and consists in some embodiments in thin layers of metal oxides alternated with thin, transparent layers of metal. Preferably, the low-e coating is coated in the number four surface 104 when the laminate comprises two glass layers. The low-e coating may comprise for instance one or more transparent layers of metal oxide layer and/or thin layers of silver or silver alloys. A skilled person would understand that the thickness of this kind of films is such that there is no need to include compensation films or spacers in order to avoid problems during the lamination of the glazing.

A panoramic roof is a vehicle roof glazing which comprises a substantial area of the roof over at least a portion of both the front and rear seating areas of the vehicle. A panoramic windshield is a windshield on which the top edge has been substantially extended such that it comprises a portion of the vehicle roof and may be comprised of multiple glazings and may be laminated or monolithic. The following examples explain some embodiments of the present invention in more detail.

Example 1:

The thermochromic cross section of a panoramic glass roof as shown in Figure 2A, illustrates a first embodiment of the invention. The laminate is comprised of a standard soda-lime 2.1 mm thick clear exterior glass layer 201 and a 2.1 mm soda-lime 90% clear interior glass layer 202. Clear layer refers to a non-tinted or non-colored layer. A sheet of thermochromic trilayer 6 having a VLT of 6% at 60°C and a VLT of 65% at 25°C, which is inserted between the outer glass layer 201 and interior glass layer 202.

A plastic interlayer 4 made of Dark PVB of 0.76 mm is included facing surface three 103 and the sheet of thermochromic 6. The glass layers 2 are heat strengthened using any of the bending process known in the prior art. The assembled laminated is processed, using standard automotive laminating equipment. After measuring the VLT resultant for the final construction of the laminate, the present example comprised a total VLT of 0.6% at 60°C and 6% at 25°C.

Example 2:

Another embodiment of the present invention is represented in Figure 3B, the glass laminate may include a standard soda-lime 2.1 mm thick clear exterior glass layer 201 and a 2.1 mm soda-lime clear 90% interior glass layer 202. A sheet of thermochromic layer 6 having a VLT of 6% at 60°C and a VLT of 65% at 25°C, which is inserted between the outer glass layer 201 and interior glass layer 202. A coating 18 is applied over the number two surface 102. Additionally, a low-e coating 43 is incorporated over the number four surface 104. The laminate is combined with additional dark PVB 4 of 0.76 mm facing surface three 103 plastics in order to increase the obscuration level. The glass layers 2 are heat strengthened using any of the bending process known in the prior art. After measuring the VLT resultant for the final construction of the laminate, the present example comprised a total VLT of 0.6% at 60°C and 6% at 25°C. Example 3:

Another embodiment of the invention shown in Figure 4A comprises a laminate comprised of a standard soda-lime 2.1 mm thick clear exterior glass layer 201 and a 2.1 mm soda-lime 90% clear interior glass layer 202. A sheet of thermochromic trilayer 6 having a VLT of 6% at 60°C and a VLT of 65% at 25°C, which is inserted facing surface two 102 of the outer glass layer 201. A dark PVB interlayer 4 of 0.76 mm thickness is included facing surface three 103 and the sheet of thermochromic 6. A metallic film 42 (heating means) is placed between the thermochromic interlayer 6 and the dark PVB interlayer 4. The metallic film 42 will reflect the infrared and will heat the thermochromic interlayer 6, increasing and optimizing the energy speeding up the change from clear to dark of the thermochromic interlayer 6. Optionally, a low-e material 43 is coated in surface four 104. The combination of metallic coating and low- e material will reflect the IR and block the heat, increasing the efficiency of the obscuration of the laminate. After measuring the VLT resultant for the final construction of the laminate, the present example comprised a total VLT of 0.6% at 60°C and 6% at 25°C.

Example 4:

Another embodiment of the invention shown in Figure 4B comprises a laminate comprised of a standard soda-lime 2.1 mm thick clear exterior glass layer 201 and a 2.1 mm soda-lime 90% clear interior glass layer 202. A sheet of thermochromic trilayer 6 having a VLT of 6% at 60°C and a VLT of 65% at 25°C, which is inserted between the outer glass layer 201 and interior glass layer 202. A dark PVB interlayer 4 of 0.76 mm thickness is included facing surface three 103 and the sheet of thermochromic 6. A metallic film 42 with busbars 50 is placed in contact with surface three 103 and the plastic interlayer 4, a low-e material 43 is coated in surface four 104. Busbars 50 can be thin copper used to power the metallic film 42. On a sunny day, the thermochromic layer 6 increases its temperature and hence changing the darkness to a VLT of 0.6%. During a sunny day, the metallic film 42 in surface three 103 and the metallic film 42 in surface four 104 reflect the light near IR, reducing the amount of heat in the interior of the roof and helping to the obscuration of the laminate. If required, a user can increase the darkness of the laminate by activating the metallic film 42 and hence heating the glass. In this case, the metallic film 42 can be connected to a set of electrodes that will inject current through the metallic film 42. The battery usage of the car will not be affected that much since the car will be moving. After measuring the VLT resultant for the final construction of the laminate, the present example comprised a total VLT of 0.6% at 60°C and 6% at 25°C.

It must be understood that this invention is not limited to the embodiments described and illustrated above. A person skilled in the art will understand that numerous variations and/or modifications can be carried out that do not depart from the spirit of the invention, which is only defined by the following claims.

Claims

1. A glass laminate, comprising:

an outer glass layer;

an inner glass layer;

an intermediate layer comprising:

a thermochromic material placed in contact with any of the interior surfaces of the outer or the inner glass layers;

a dark plastic interlayer placed in contact with any of the interior

surfaces of the outer or the inner glass layers;

wherein the thermochromic material is of variable transmissivity which is determined by either the temperature of the thermochromic material or the incident solar light radiation such that a change in said temperature or light radiation results in a change in the visible light transmittance (VLT) of the total glass laminate;

wherein the VLT of the total glass laminate ranges between 0.1% to 10%.

2. The glass laminate of claim 1, wherein the VLT of the glass laminate ranges between 0.6% to 6%.

3. The glass laminate of claim 1, further comprising an infrared reflecting film or coating facing a major surface of any of the interior or exterior glass layers.

4. The glass laminate of claim 1, further comprising heating means.

5. The glass laminate of claim 1, wherein the glass layers are of soda lime, borofloat or aluminium silicate.

6. The glass laminate of claim 1, wherein the plastic interlayer is selected from the group consisting of polyvinyl butyl (PVB), ionoplast polymers, ethylene vinyl acetate (EVA), cast in place (CIP) fluid resin and thermoplastic polyurethane (TPU).

7. The glass laminate of claim 1, wherein the plastic interlayer is a PVB with nano particles that absorb partially the infrared heat of the sun.

8. The glass laminate of claim 1, wherein the glass is a soda-lime glass clear, green, solar green, grey, blue or brown color.

9. The glass laminate of claim 1, further comprising a metallic coating over a major surface of any of the glass layers.

10. The glass laminate of claim 1, further comprising an anti-reflection film disposed on at least one of upper and lower surfaces of the thermochromic film.

11. The glass laminate of claim 13, wherein the anti-reflection film is made of an oxide of one selected from the group consisting of Ti, Zn, Nb, Sn and Zr or a nitride of Si.

12. The glass laminate of claim 1, wherein an infrared reflecting layer is positioned between the outer glass layer and the inner glass layer.

13. The glass laminate of claim 1, wherein the thermochromic material can be of different geometric shapes.

14. The glass laminate of claim 1, wherein the glass layers are either chemically, heat strengthened or thermally tempered.