WO2022266484A1

WO2022266484A1 - Glass product and method of producing glass product

Info

Publication number: WO2022266484A1
Application number: PCT/US2022/034058
Authority: WO
Inventors: Wladislaw BRONSTEIN; Philippe DULSKI; Markus Walter POHLEN
Original assignee: Carlex Glass America, Llc
Priority date: 2021-06-17
Filing date: 2022-06-17
Publication date: 2022-12-22

Abstract

A glass product includes a glass piece, a first adhesive layer on the glass piece, a switchable film having variable light transmission adhered to the glass piece via the first adhesive layer, a second adhesive layer on the switchable film, and a protective layer adhered to the switchable film via the second adhesive layer, wherein the protective layer includes a light guide connected to a light source.

Description

GLASS PRODUCT AND METHOD OF PRODUCING GLASS PRODUCT

Cross Reference to Related Applications

[0001] This application claims priority to U. S. Provisional Application No. 63/211 ,754 filed on June 17, 2021, entitled "GLASS PRODUCT,” the entire contents of which are incorporated by reference herein in their entirety.

Technical Field

[0002] The present disclosure is generally related to a glass product having a switchable film and a protective layer over the switchable film, wherein the protective layer provides a light guide, The present disclosure is also generally related to a method of producing the glass product.

Background

[0003] Switchable films, functional ly changing in light transmission under electrical power, may be used in automotive glazings to provide variably transparent windows. The switchable films may be laminated in a glazing between two glass sheets, which may include deairing and autoclaving the switchable film between glass sheets. The glass sheets may include a complex curved shape. The laminated process may be complex with a laminated functional fi lm which may wrinkle when i am mated between the glass sheets having complex curvature and may require electrical connections to be formed within the glazing. The difficulty in producing such parts may lead to unacceptable parts being produced, which may be scrapped as unusable. An alternative method for providing a switchable glazing may he needed to improve on these difficulties, among others.

Summary of the Disclosure

[0004] Disclosed herein is a glass product that includes a glass piece; a first adhesive layer; a switchable film having variable light transmission adhered to the glass piece via the first adhesive layer; a second adhesive layer; and a protective layer adhered to the switchable film via the second adhesive layer, wherein the protective layer includes a light guide connected to a light source. [0005] In some embodiments of the present disclosure, the light source may include a light emitting diode.

[0006] In some embodiments of the present disclosure, the glass product may be a sunroof.

[0007] In some embodiments of the present disclosure, the switchable film and the light source may be controlled separately. j0008j In some embodiments of the present disclosure, the protective layer may include a light extracti on portion .

[0009] In some embodiments of the present disclosure, the protective layer may include two polymer carrier film layers and a silicone core layer between the polymer carrier film layers. [0010] In some embodiments of the present disclosure, the protective Sa ver per sc may serve as a light guide.

10011 j In some embodiments of the present disclosure, the light source may provide multiple colons of l ight.

10012 j In some embodiments of the present disclosure, the protective layer may have a thickness of 1.0 mm or less.

{00! 3 j In some embodiments of the present disclosure, at least one of the first and the second adhesive layers may be a coating.

{0014] In some embodiments of the present disclosure, at least, one of the first and the second adhesive layers may include a pressure-sensitive adhesive or a cured material of a photocurabie, reaction-curable, or moisture-curable adhesive.

{0015] In another aspect of the present disclosure, a method of producing the glass product of the present disclosure includes: adhering the protective layer to the switchable film via the second adhesive layer; adhering the switchable film to the glass piece via the first adhesive layer; and connecting the light source with the light guide.

[06.16] In some embodiments of the present disclosure, the glass piece may have a curved shape, and the switchable film with the protective layer adhered thereto may be shaped prior to adhering to the glass piece.

{0017] In some embodiments of the present disclosure, at least one of the first and the second adhesive layers may include a photoe arable, reaction-curable, moisture-curable, or pressure- sensitive adhesive, and the adhering of at least one of the protective layer and the adhering of the switchable film may be carried out at mi ambient temperature.

Brief Description of the Drawings

{0018] The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate one or more example aspects of the present disclosure and, together with the detailed description, serve to explain their principles and implementations. 10019] FIG. I is a cross section illustrating a glass product, according to an exemplary embodiment of the present disclosure.

10020] FIG. 2 is a cross section illustrating a glass product, according to an exemplary embodiment of the presen t discl osure.

10021 ] FIG. 3 is a cross section illustrating a glass product, according to an exemplary embodiment of the present disclosure.

10022] FIGs. 4A, 4B, and 4C illustrate steps of producing a glass product, according to an exemplary embodiment of the present disclosure.

100233 FIG. 5A illustrates a step of producing a glass product, according to an exemplar}' embodiment of the present disclosure.

|0024] FIG. SB is a cross section illustrating a glass product, according to an exemplary embodiment of the present disclosure.

Detailed Description

100253 la the following description, for purposes of explanation, specific details are set forth in order to promote a thorough understanding of one or more aspects of the disclosure, It may be evident in some or all instances, however, that any aspects described below can be practiced without adopting the specific design details described below.

100263 This disclosure relates generally to a glass product, including: a glass piece; a first adhesive layer on the glass piece; a switch able film having variable light transmission adhered io the glass piece via the first adhesive layer; a second adhesive layer on the switchable film; and a protective layer adhered to the switchable film via the second adhesive layer, wherein the protective layer includes a light guide connected to a light source. This disclosure also relates generally to a method of producing the glass product, including: adhering the protective layer to the switchable film via the second adhesive layer; adhering the switchable film to the glass piece via the first adhesive layer; and connecting the light source with the light guide.

[0027] Where a switchable film is laminated between interlayers in a laminated glazing, the relatively soft interlayers may allow for change in shape of the switchable film, including wrinkling of the film, Applying the film instead to a harder glass surface may allow for prevention or limitation of such wrinkling even where the glass has a complex curvature shape.

[0028] Glass products described herein may include laminated or non- laminated glazings. Such glazings may be used, for example, in automotive vehicles as windows, such as windshields. sunroofs, back windows, or side window's. The glass product may include a glass piece which may include a single glass sheet or a laminated glazing. The glass pieces may be bent to a desired shape. A conventional laminated glazing may include a first glass sheet, an interlayer, and a second glass sheet laminated together. The glass sheets may be bent to a desired shape prior to lamination with an interlayer therebetween. Preferably, the glass sheets may be a soda-lime silica glass. Glass bending may preferably occur by heat treatment from 550°C to 70Q°C, more preferably from 5S0°C to 660°C. The interlayer may include an adhesive polymer sheet, which may include polyvinyl butyral (PVB) or ethylene vinyl acetate (EVA), An interlayer may include an ionomer sheet in some glazings. An inner glass sheet of the glazing bices a vehicle interior when installed, and an outer glass sheet faces a vehicle exterior when installed. The glass product may be a sunroof

[0029] A switchable film as used herein may include a functional layer for changing in transparency due to a connection to an electrical power source. Switchable films may include, for example, a liquid crystal film, such as polymer dispersed liquid crystal (PDLC), polymer network liquid crystal (PNLC), or other liquid crystal films, a nanoparticle film, such as a suspended particle device (SPD), or e!ectrochromic films. A switchable film may include, for example, a first base layer, a first electrode on the first base layer, a functional layer, a second electrode, and a second base layer. The second electrode may be formed on the second base layer. The first and second electrodes may preferably include a metal oxide, such as indium tin oxide and may be the same or different material. The first and second base layers may preferably include polymer films, such as polyethylene terephthalate (PET) and may be the same or different from each other. The first and second electrodes may be independently connected to a power source. Some switchable films may be segmented so that the segments formed may be controlled independently of each other. Segments may be formed by creating electrically isolated portions on one or both of the first and second electrodes. The segments may each require electrical connection via a busbar. The switchable film may connect to a power source via busbars formed on the electrodes. The functional layer may include any suitable material and may include, for example, liquid crystal for PDLC or PNLC or nanoparticles for SPD. When the switchable film is connected to an electric power source, the switchable film may switch from a dark or opaque state to a clear state, or vice versa. |0030j As disclosed herein, a switchable film may be adhered to a glass piece, or glazing. Particularly the switchable film may be adhered to the glass piece on an inner surface facing a vehicle interior when installed. The switchable film may be adhered by an adhesive layer which may include, or be formed by, a hot-melt, thermosetting, photoc arable, reaction-curable, raoisrure- curable, or pressure-sensitive adhesive. The adhesive may include compounds based on acrylate, urethane, urethane acrylate, epoxy, epoxy acrylate, acryl, silicone, isocyanate, polyolefin, modified olefin, polypropylene, ethylene vinyl alcohol, vinyl chloride, chloroprene rubber, cyanoacrylate, polyamide, polyimide, polystyrene, polyvinyl butyral, ethylene vinyl acetate, or the like. The preferable adhesive may be selected for suitable workability and adhesion properties, as well as for providing suitable optical transparency.

|0031 j It may be desirable to cover such a switchable film with a protective layer so as to protect it from an environment in the vehicle. The protective layer may be applied over the switchable film with an adhesive that may be the same or different from the adhesive used to adhere the switchable film to the glass piece. The protective layer may preferably have a thickness of 1.0 mm or less, more preferably 0.7 mm or less. The protective layer may include a polymer layer or a glass layer, f or example, the protective layer may include a polymer film, such as a polyethylene terephtha!ate (PET) film, a polycarbonate film, or an acrylic film, and the polymer film may have a hard coating, such as an acrylic coating, thereon. The adhesive and protective layer may have a suitable optical appearance to be applied to a glass piece, which may preferably include a sunroof. Where the protective layer is a glass protective layer, a glass sheet, which may be thin and flexible, may be the glass protective layer. The glass protective layer may preferably have a thickness of 1.0 mm or less, more preferably 0.7 nun or less, and may be chemically strengthened.

104132] The protective layer may be larger in size than the switchable film so as to extend past the switchable film and completely cover it. Where the protective layer extends past an edge of the switchable film, the protective layer may be partially adhered to the glass piece so that the switchable film may be completely enclosed between the glass piece and the protective layer. Where all or part of the protective layer does not extend past the edge of the switchable film, the edges of the switchable film and the protective layer may be covered with a sealant. Where the protective layer does extend past the edge of the switchable film, the protective layer and the second adhesive may seal the edge of the switchable film. An additional sealant may be used in combination with the second adhesive. The protective layer may have flexibility to conform to the shape of the glass piece and the switch able film on the glass piece.

[0033] The protective layer may have physical and chemical protective qualities. Particularly, the protective layer may have a haze value of less than 2% after the Taber test, as described in ECE R43 (updated May 3019). Further, the protective layer may have a chemical resistance which may pass the chemical resistance test as defined in ECE R.43 (updated May 2019).

[0034] The protective layer may preferably include a light guide 50, 51, 52 connected to a light source 80 for providing light to a vehicle interior, as shown in FIGs. 1 to 3. The protective layer per se may serve as a light guide 50, 51, 52. The light guide 50, 51, 52 may be positioned at the outermost layer of the glass product 100, 101, 102 so as to face a vehicle interior when the glass product is installed in a vehicle.

[0035] The switchable film 10 may limit light from the light source 80 and light: guide 50, 51, 52 that may be seen from a vehicle exterior. The light guide 50, 51, 52 may have a visible light transparency across the glass product 100, 101, 102 such that light may transmit through at least part of the glass produc t 100, 101 , 102 into the vehicle. The protective layer light guide 50, 51 , 52 may have flexibility to conform to the shape of the glass piece 110 and the switchable film 10 on the glass piece 110.

[0036] As shown in FIG. 3, the protective layer light guide 52 may include, for example, two outer carrier film layers 52b, 52c sandwiching a silicone core layer 52a therebetween, which may serve as the light guide 52, The silicone core layer 52a may have an index of refraction different from the carrier film layers 52b, 52c such that light introduced to the silicone core layer 52a may be reflected within the sil icone core layer 52a. Preferably, the silicone core layer 52a has an index of refraction higher than that of the carrier film layers 52b, 52c. The carrier film layers 52b, 52c may include polymer carrier film layers, such as polyethylene terephthalate.

[0037] The light guide 52 may have a light introduction mechanism for introducing light to the light, guide 52. The light may be introduced to the silicone core layer 52a of the light guide 52 at an angle greater than a critical angle, such that total internal reflection is possible within the silicone core layer 52a. The critical angle may be measured with respect to the normal to the surface of the carrier film layer 52b, 52c. Preferably, the earner film layers 52b, 52c are parallel to each other, such that the silicone core layer 52a has an even thickness across the laminated glazing, i,e,, glass product 102, The light wave may not pass through the bo unds of the light guide

(> 52 where the light guide 52 has a higher refractive index than its surroundings and the reflective angle is greater than a critical angle. The light’s angle is greater as it moves towards parallel with the light guide borders. The critical angle may depend on the waveguide and surrounding materials, including their retractive indices. Particularly, the critical angle, 0c, may be defined by equation (3):

wherein Bcx^'s the critical angle, m is the refractive index of the material surrounding the light guide, and m is the refractive index of the Sight guide 52.

|0038] The protective layer may serve as a monolayer light guide 51 when it. has a higher refractive index than its surroundings, i.e._t the second adhesive layer 141 and air, as shown in FIG. 2. Alternatively, when the refractive index of the second adhesive layer 141 is almost the same as the refractive Index of the light guide 51, an additional layer with a lower retractive index than the light guide 51 may be positioned between the second adhesive layer 141 and the light guide 51. The light guide 51 may be transparent across the glass product such that light may transmit through the light guide 51. The total visible light transmission of the light guide 51 may be at least 70 %. The total light ltansmiitanee maybe determined according to ISO 9050:2003, “Glass in building — Determination of light transmittance, solar direct transmittance, total solar energy transmittance, ultraviolet transmittance and related glazing factors”. To measure light transmission across a wavelength spectrum or at a particular wavelength, including the visible light wavelength range (380nm-780nm), any suitable equipment complying with the ISO 9050:2003 may be used, such as a UV-Vis Spectrophotometer (e.g._t U4000, Hitachi High-Tech Science).

|0039] The light source 80 for such a light guide 50, 51, 52 may be provided at the edge of the light guide 50, 51, 52 and may include one or more light emitting diodes (LEDs). The light, source 80 may be connected electrical ly independent of the switehabSe film 10 such that the light source 80 and the switchable film 10 may be powered or controlled separately, Le., Independently of eaeh other. The light source 80 may provide one or multiple colors of light, including white. The Sight may be extracted from the light guide 50, 51, 52 by diffraction or luminescence. The light guide 50, 51, 52 may further include a light extraction portion 85, which may be a print or a pattern for light extraction. The light extraction portion 85 may be visible, in some embodiments, when the light is on and when the light is off. The light extraction portion 85 may include a hologram, a print containing light scattering particles, a diffraction film, or a surface etched by laser radiation. Preferably, where the light extraction portion 85 is on the light guide 50, 5 i, 52, the light extraction portion 85 of the light guide 50, 51, 52 may face a vehicle interior. Where the light guide 52 includes multiple layers, including a silicone core layer 52a, the light extraction portion 85 may particularly be on a surface in contact with the silicone core layer 52a. The protective layer, or the light guide, 51, 52 may include at least one light extraction portion 85 as shown in FIGs, 2 or 3. {0040] The protective layer 50. 51, 52 may further include an area for capacitive switching of the switchahle film 10, which may he connected to the switchable film 10. For example, the protective layer 50, 51, 52 may have a multi-layer structure in this area which has a dielectric layer sandwiched by two conductive layers or a single layer structure. A protective layer 50, 51, 52 with such a structure may provide a capacitive switching, or a touch panel. An electrical connection from a power source to the capacitive switching may be formed in this area. ^'Phis area may be marked to indicate the position of the capacitive switching,

10(141] Each of FIGs. 1 to 3 illustrates a glass product 100, 101 or 102 according to an exemplary embodiment of the present disclosure. The glass product 100, 101, 102 includes a glass piece 110; a first adhesive layer 130 on the glass piece 110; a switchable film 10 having variable light transmission adhered to the glass piece 110 via the first adhesive layer 130; a second adhesive layer 140, 141 on the switchable film 10; and a protective layer 50, 51, 52 adhered to the switchable film 10 via the second adhesive layer 140, 141, wherein the protective layer 50, 51, 52 includes a light guide 50, 51, 52 connected to a light source 80. The protective layer 51 shown in FIG, 2 includes light extraction portions 85. The protective layer 52 shown in FIG.3 includes two polymer carrier film layers 52b, 52c and a silicone core layer 52a between the polymer carrier film layers 52b, 52c, and further includes light extraction portions 85 on the silicone core layer 52a.

10042] The glass product 100, 101, 102 may be produced by a method including: adhering the protective layer 50, 51, 52 to the switchable film 10 via the second adhesive layer 140; adhering the switchable film 10 to the glass piece 110 via the first adhesive layer 130; and connecting the light, source 80 with the light guide 50, 51, 52.

10043] FIGs. 4 A, 4B, and 4C illustrate steps of producing the glass product 100, according to an exemplary embodiment of the present disclosure. A protective layer including a light guide 50 maybe adhered to a switchable film 10 via a second adhesive layer 140 as shown in FIG. 4A, The switchable film 10 with the protective layer light guide 50 may then be adhered to a glass piece

HO via a first adhesive layer 130 as shown in FIG. 4B. A light source 80 may then be connected with the light guide 50 as shown in FIG. 40. A light extraction portion 85 may be provided to the protective layer light guide 50 either before adhering the protective layer to the switehable film 10 or after both the switehable film 10 and the protective layer light guide 50 are adhered to the glass piece 1 10.

10044] As shown in FIG. 5A, the glass piece 111 may have a curved shape. After adhering the protective layer light guide 50, 51, 52 to the switehable film 10 via the second adhesive layer 140, the switehable film 10 may be shaped or curved prior to adhering to the glass piece 1 11.

{0045] FIG. 5 A illustrates a step of producing the glass product 103 shown in FIG. 5B, according to an exemplar}' embodiment of the present disclosure. When a glass piece 111 has a curved shape, the switehable film 10 with the protective layer light guide 50 may be shaped or curved prior to adhering to the glass piece 111.

[0046] Adhering the switehable film 10 with the protective layer light guide 50. 5 !, 52 to the glass piece 110, 1 1 1 may be carried out by laminating the switehable film 10 and the glass piece 1 10, 111 with the adhesive layer 130 therebetween, which may include adhering them via a vacuum, such as a vacuum bag degassing, or physically pressing them with a roller. The adhering may preferably be processed in a vacuum or double- vacuum thermoforming process such that the first contact of the adhesive layer 130 and the glass piece 110, 11 1 will be under vacuum which may avoid air bubbles in the interface between the glass piece 110, 1 11 and the adhesive layer 130. [0047] At least one of the first and the second adhesive layers 130, 140 may be a coating. In other words, at least one of these adhesive layers 130, 140 may be formed by coating an adhesive. The adhering may be carried out at an ambient temperature, t.e. about 10 to 40°C, when the first and the second adhesive layers 130, 140 include, or are formed by, a phoiocurab!e, reaction-curable, moisture-curable, or pressure-sensitive adhesive. Adhering at an ambient temperature may be preferable as it may avoid damage to the switehable film 10 caused by heating.

[0048] The above description of the disclosure is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the common principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Further, the above description in connection with the drawings describes examples and does not represent the only examples that may be implemented or that are within the scope of the claims. |0049j Furthermore, although elements of the described aspects and/or embodiments may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated. Additionally, all or a portion of any aspect and/or embodiment may be utilized with all or a portion of any other aspect and/or embodiment, unless stated otherwise. Thus, the disclosure is not to he limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A glass product, comprising: a glass piece; a first adhesive layer on the glass piece; a switchable film having variable fight transmission adhered to the glass piece via the first adhesive layer; a second adhesive layer on the switchable film; and a protective layer adhered to the switchable film via the second adhesive layer, wherein the protective layer includes a light guide connected to a light source,

2. The glass product according to claim I, wherein the light source includes a light emitting diode.

3. The glass product according to claim 1 or 2, wherein the glass product is a sunroof.

4. The glass product according to any one of claims 1 to 3, wherein the switchable film and the light source are controlled separately.

5. The glass product according to any one of claims 1 to 4, wherein the protective Saver includes a light extraction portion.

6. The glass product according to any one of claims 1 to 5, wherein the protective layer includes two polymer carrier film layers and a silicone core layer between the polymer carrier film layers.

7. The glass product according to any one of claims i to 6, wherein the protecti ve layer per se serves as a light guide,

8. The glass product according to any one of claims 1 to 7, wherein the light source provides multiple colors of fight.

9. The glass product, according to any one of claims 1 to 8, wherein the protective layer has a thickness of 1.0 mrn or less,

10. The glass product according to any one of claims 1 to 9, wherein at least one of the first and the second adhesive layers is a coating.

11. The glass product according to any one of claims 1 to 10, wherein at least one of the first and the second adhesive layers include a pressure-sensitive adhesive or a cured material of a photocurable, reaction-curable, or moisture-curable adhesive,

12. A method of producing the glass product according to any one of claims 1 to ί 1 , the method comprising; adhering the protective layer to the switchable film via the second adhesive layer; adhering the switchable film to the glass piece via the first adhesive layer; and connecting the light source with the light guide,

13. The method according to claim 12, wherein the glass piece has a curved shape, and the switchable film with the protective layer adhered thereto is shaped prior to adhering to the glass piece.

14. The method according to claim 12 or 13, wherein at least one of the first and the second adhesive layers includes a photocurable, reaction-curable, moisture-curable, or pressure-sensitive adhesive, and at least one of the adhering the protective layer and the adhering the switchable film is carried out at an ambient temperature.