CN113348075A

CN113348075A - Insulating glass unit with low CTE center pane

Info

Publication number: CN113348075A
Application number: CN201980090416.8A
Authority: CN
Inventors: M·A·麦克唐纳德
Original assignee: Corning Inc
Current assignee: Corning Inc
Priority date: 2018-11-30
Filing date: 2019-11-26
Publication date: 2021-09-03
Also published as: TW202104134A; WO2020112754A1; KR20210099602A; JP2022513155A; EP3887151A1

Abstract

An insulating glass unit comprising: the first pane, the second pane, and the third pane between the first and second panes, as well as a first seal gap space between the first pane and the third pane and a second seal gap space between the second pane and the third pane. The third pane comprises the first glassA sheet having a temperature range of from 0 to about 300 ℃ of less than about 70x10^‑7Coefficient of Thermal Expansion (CTE) of/° C.

Description

Insulating glass unit with low CTE center pane

CROSS-REFERENCE TO RELATED APPLICATIONS

Priority of U.S. provisional application nos. 62/773,287, 62/773,378, and 62/773,382, filed 2018, 11, 30, 35 us.C. § 119, herein incorporated by reference in their entirety.

Technical Field

The disclosure herein relates generally to Insulated Glass Units (IGUs) comprising two or more glass panes, at least one of which, or at least one of which, a glass sheet assembly, has, for example, less than about 70x10^-7Low Coefficient of Thermal Expansion (CTE)/deg.c. The low CTE center pane also enables a thinner center pane, for example less than 0.9mm in thickness. The present disclosure also generally relates to an Insulating Glass Unit (IGU) that includes a laminated center pane comprising two low CTE glass sheets. The present disclosure also generally relates to methods of manufacturing such IGUs, including those having one or more thin center panes, at least one of which includes a low emissivity ("low E") coating applied on at least one surface thereof.

Background

Insulating Glass Units (IGUs) can be used as components in a wide variety of applications, including: buildings, automobiles, displays, and electrical components. IGUs may be used as multi-pane windows in buildings or automobiles to provide thermal insulation from the outside ambient temperature. IGUs typically include two or more glass panes sealed at their peripheral edges by a sealant. The panes are spaced apart and once sealed, the space between each pane may be filled with an inert gas (e.g., argon or krypton) or a mixture of inert gases. Thereby, the thermal insulation or performance of the IGU may be improved. Generally, however, the full benefit of sealing the insulating glass layer is achieved by adding one or more low emissivity ("low E") coatings to one or more surfaces of the pane. The low E coating functions to reduce the transfer of thermal energy from the pane to the pane by radiation or radiation absorption.

In addition to thermal and insulating properties, IGUs typically comply with other design constraints, including for example: weight, thickness, light transmittance, mechanical strength, and/or manufacturing cost.

Three-pane IGUs (e.g., three glass panes with two air cavities) exhibit improved thermal and insulating performance compared to two-pane IGUs (e.g., two glass panes with one air cavity), which is manifested as an improvement in Solar Heat Gain Coefficient (SHGC) and/or insulation U value of about 20-30% or more. However, triple-pane IGUs may exhibit undesirable weight, thickness, and/or manufacturing costs. Furthermore, the additional weight, thickness, and/or manufacturing costs associated with the additional panes can negatively impact the IGU, making it undesirable for certain applications.

It has previously been proposed to reduce the thickness of the central pane. However, since the central pane is insulated on both sides, it reaches much higher temperatures and therefore much higher stress levels than the inner and outer panes, generally requiring the glass of the central pane to be heat strengthened to improve its mechanical strength sufficiently to resist the stresses due to thermal gradients. In order to establish adequate strengthening by thermally strengthening soda-lime-silicate window glass, a sheet thickness of at least 1.5-2mm is typically required, which hinders the use of very thin (e.g., less than 1mm) glass and the advantages of such very thin glass.

As noted above, while a thin center pane is desirable for weight reduction considerations, the thermal tempering process suffers from difficulties in providing sufficient strength on the sheet to resist the thermal stresses generated in the center pane of the IGU. Furthermore, the handling and manipulation necessary to cut and install a very thin glass sheet as a center pane or layer of an IGE can be difficult to perform/implement. One way to overcome these difficulties is to use very thin glass sheets that have been chemically strengthened. Chemical strengthening can alleviate handling requirements and allow the sheet to withstand thermal stresses generated as a center pane. However, the manufacturability of such chemically strengthened sheet glass is a potential issue in window designs where a center pane requires a low E coating on one or both sides. For example, low E coatings are most effective on large sheet top surfaces, but low E coated sheets cannot be chemically strengthened. Furthermore, if chemical strengthening is applied to a large sheet, which is later cut to window size, this is often a sensitive and difficult process that can suffer from breakage losses, although it is feasible. Such results are disadvantageous for large scale manufacturing. In addition, most or all of the chemically strengthened strength at the edges of the sheet material is lost due to the cutting process. As a result, enhanced processing benefits may not be realized, and the resulting manufacturing economy may not be particularly advantageous. Alternatively, first cut to size and then strengthened, coating is also economically unattractive as a manufacturing process because of the need for customized separate sheet coating and strengthening. Furthermore, reducing the thickness of the center pane tends to reduce the acoustic performance (noise attenuation) of the IGU. Thus, the handling and manipulation necessary to cut and install a very thin glass sheet as a center pane or layer of an IGE having the desired design and performance characteristics can be difficult to perform and achieve.

Disclosure of Invention

The present disclosure relates to an insulating glass unit comprising: the first pane, the second pane, and the third pane between the first and second panes, as well as a first seal gap space between the first pane and the third pane and a second seal gap space between the second pane and the third pane. The third pane comprises a first glass sheet having a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7Coefficient of Thermal Expansion (CTE) of/° C. The third pane may include first and second glass sheets laminated together by a polymeric interlayer, and the first and second glass sheets exhibit a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7Coefficient of Thermal Expansion (CTE) of/° C.

According to another embodiment of the present disclosure, an insulated glass unit ("IGU") is described that includes an insulated glass unit (1101) that further includes a first pane, a second pane, a third pane and a fourth pane disposed between the first and second panes. A first sealed interstitial space is defined between the first pane and the third pane. Second sealAn interstitial space is defined between the third pane and the fourth pane, and a third sealed interstitial space is defined between the second pane and the fourth pane. The third pane comprises a first glass sheet having a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7Coefficient of Thermal Expansion (CTE) of/° C. The third pane may include first and second glass sheets laminated together by a polymeric interlayer, and the first and second glass sheets have a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7Coefficient of Thermal Expansion (CTE) of/° C. The fourth pane can similarly include first and second glass sheets laminated together via a polymeric interlayer, the first and second glass sheets having a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7Coefficient of Thermal Expansion (CTE) of/° C.

According to another embodiment of the present disclosure, a method of making an insulating glass unit comprises: cutting a third pane having a selected size from a larger glass sheet having less than about 70x10 over a temperature range of 0 to about 300 ℃^-7Coefficient of Thermal Expansion (CTE)/DEG C; the third pane is then assembled with the first and second panes, or the third pane is assembled with the first, second, third, and fourth panes, thereby forming an insulating glass unit with the third pane positioned between the first and second panes, defining a first sealed interstitial space on one side of the third pane and a second sealed interstitial space on the other side of the third pane.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the methods as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description present various embodiments of the invention, and are intended to provide an overview or framework for understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the disclosure and, together with the description, serve to explain the principles and operations of the disclosure.

Drawings

The following detailed description can be further understood when read in conjunction with the following drawings, wherein:

fig. 1 is a cross-sectional view of a three-pane IGU according to an embodiment of the present disclosure;

fig. 2 is a cross-sectional view of a three-pane IGU according to an embodiment of the present disclosure;

fig. 3 is a cross-sectional view of a four-pane IGU according to an embodiment of the present disclosure;

FIG. 4 illustrates a method of fabricating an IGU according to an embodiment of the present disclosure;

FIG. 5 shows EAGLE in a three-layer IGU at +60 deg.C

Maximum principal stress on the central layer of glass;

FIG. 6 shows EAGLE in a three-layer IGU at-40 deg.C

Deflection of the central layer of glass;

FIG. 7 is a graph of deflection (sag) as a function of thickness for a leading edge of a glass sheet processed on a roller bed conveyor with a typical roller spacing;

FIG. 8 is a graph of deflection and stress as a function of sheet thickness for a glass sheet at its edge subject to a constraint having a thermal gradient across the thickness.

Detailed Description

Various embodiments of the present disclosure will now be discussed with reference to fig. 1-8, which illustrate exemplary embodiments of IGUs and their components, features, or properties. The following general description is intended to provide an overview of the claimed apparatus, and various aspects will be discussed in more detail throughout this disclosure with reference to illustrated non-limiting embodiments, which are interchangeable within the disclosure.

Disclosed herein are Insulated Glass Units (IGUs) comprising a first pane, a second pane, and a third pane disposed between the first and second panes. One embodiment of an IGU 1000 is shown in cross-section in fig. 1. Other embodiments are shown in cross-section in fig. 2 and 3. In some embodiments, the third pane comprises a glass laminate comprising two glass sheets with an intermediate polymer film. The one or more glass sheets comprising the center pane can have a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7Coefficient of Thermal Expansion (CTE) of/° C.

As shown in fig. 1, which is one embodiment of an IGU 1000, the IGU includes three

panes

110, 120, and 130. The first (outer) pane 110 may be positioned with its outer surface 112 facing the external ambient environment. The second (inner) pane 120 may be positioned with its outer surface 122 facing inward, such as the inside of a building, automobile, or appliance. A third (center) pane 130 may be disposed between and spaced apart from the

panes

110, 120. The third pane 130 may be arranged substantially parallel to the first and

second panes

110, 120.

Panes

110, 120, 130 can all be optically transparent, or one or more layers thereof, or one or more portions or components thereof can be translucent, opaque, or semi-opaque. The third pane 130 comprises at least one glass sheet having a CTE less than about 70x10 over a temperature range of 0 to about 300 ℃^-7/° c, or less than about 50x10^-7/° c, or less than about 35x10^-7V. C. In some embodiments, such as IGU 1100 shown in fig. 2, the third pane 130 comprises a glass laminate comprising: first and

second glass sheets

131, 132, and an intermediate polymer film or interlayer 133.

According to various embodiments, the first and

second panes

110, 120 may be thicker than the third pane 130. In some embodiments, the first pane 110 is thicker than the third pane 130. In other embodiments, the second pane 120 is thicker than the third pane 130. In some embodiments, the thickness range of the

panes

110, 120 may be: from about 2mm to about 16mm, or from about 2mm to about 10mm, for example: from about 3mm to about 8mm, alternatively from about 4mm to about 7mm, alternatively from about 5mm to about 6mm, including all ranges and subranges therebetween. In a non-limiting mannerIn an embodiment, the first and

second panes

110, 120 may include: soda-lime silicate glass, but other glass types may be used, without limitation, such as: aluminosilicate and alkali aluminosilicate glasses, or other similar glasses. In various embodiments, the Coefficient of Thermal Expansion (CTE) of the first and/or

second panes

110, 120 can be greater than about 70x10^-7/° c, for example: greater than about 75x10^-7/° c, or greater than about 80x10^-7/° c, or greater than about 85x10^-7/° c, or greater than about 90x10^-7/° c, or greater than about 95x10^-7/° c, or greater than about 10x10^-6/° c, including all ranges and subranges therebetween, for example: about 70x10^-7/° c to about 15x10^-6/℃。

According to various embodiments, one or both of the first and

second panes

110, 120 may be strengthened by, for example, thermal tempering, chemical strengthening, or other similar processes to improve the mechanical strength of one or both of these layers. In some embodiments, the first and

second panes

110, 120 can be produced by a float or fusion draw fabrication process.

In certain embodiments of the present disclosure, the inner surface 114 of the first pane 110 may be partially or fully coated with at least one layer of a first coating 117 (e.g., as shown in fig. 1), such as a low emissivity coating for improved thermal performance. Low emissivity coatings are known in the art and may include, but are not limited to: spray-on and pyrolytic coatings, for example: one or more metals and/or metal oxides such as silver, titanium and fluorine doped tin oxide and the like. Alternatively or additionally, at least one of the major surfaces 134 (e.g., corresponding to the first sheet 131, the surface facing the gap 125 in the laminated version), 137 (e.g., corresponding to the second sheet 132, the surface facing the gap 115 in the laminated version) of the third pane 130 may be partially or completely coated with at least a coating such as a low emissivity coating 136. Alternatively or additionally, the inner surface 124 of the second pane 120 may be partially or completely coated with at least one coating, such as the low emissivity coating 116 shown in fig. 2. The coatings may be the same or different depending on the desired IGU properties and/or end use. Combinations of coatings may also be used. In various embodiments, one or more of the coatings can be optically transparent.

In a non-limiting embodiment, the third pane 130 may be thinner than the first and

second panes

110, 120. In some embodiments, the third pane 130 may have a total thickness of less than about 2mm, for example: from about 0.8mm to less than about 2mm, or from about 0.9mm to less than about 1.8mm, or from about 1mm to less than about 1.7mm, or from about 1.1mm to less than about 1.6mm, or even less than about 1.6mm or even less than about 1.5, about 1.4, about 1.2 or about 0.9mm, including all ranges and subranges therebetween. According to other aspects, the thickness of the third pane 130 is greater than about 0.4mm, or greater than about 0.5 mm.

In a non-limiting embodiment, the third pane 130 may include borosilicate glass. In another non-limiting embodiment, the third pane 130 may comprise a boroaluminosilicate glass, such as: alkaline earth boroaluminosilicate glasses are either alkali-free boroaluminosilicate glasses or other similar glass types. Exemplary commercial glass products include, but are not limited to: kang ning EAGLE

And

and (3) glass. In some embodiments, the third pane 130 may be produced by a float or fusion draw fabrication process.

According to various embodiments, the third pane 130 may have a lower CTE than the CTE of the first pane 110 and/or the second pane 120. As used herein, CTE refers to the coefficient of thermal expansion of the identified glass composition or glass sheet or pane comprising the same, as measured over a temperature range of 0 to about 300 ℃. In certain embodiments, the third window has a CTE (CTE)₃) May be less than about 70x10^-7/° c, for example: less than about 60x10^-7/° c, or less than about 50x10^-7/° c, or less than about 45x10^-7/° c, or less than about 40x10^-7/℃，Or less than about 35x10^-7/° c, or less than about 30x10^-7/° c, or even less than about 25x10^-7/° c, including all ranges and subranges therebetween, e.g., about 10x10^-7/° c to about 70x10^-7V. C. In other embodiments, the CTE of the first pane (CTE)₁) And/or the CTE (CTE) of the second pane₂) May be greater than the CTE (CTE) of the third pane₃) For example: CTE (coefficient of thermal expansion)₁>CTE₃And/or CTE₂>CTE₃Or CTE of₁≥2*CTE₃And/or CTE₂≥2*CTE₃Or CTE of₁≥2.5*CTE₃And/or CTE₂≥2.5*CTE₃Or CTE of₁≥3*CTE₃And/or CTE₂≥3*CTE₃。

As noted, one or both major surfaces of the third pane 130 can be partially or completely coated with at least one coating, such as the low emissivity coatings described above with respect to

coatings

116, 117, 136. Alternatively or additionally, one or both major surfaces of the third pane 130 may be partially or fully patterned with ink and/or surface features (e.g., decorative ink, light scattering ink, and/or light scattering surface features). Bulk scattering features below the surface within the glass matrix may also be provided in the third pane 130 by, for example, laser patterning. Surface scattering features can also be produced by laser patterning. If coatings and/or patterns are provided on both major surfaces of the third pane 130, these coatings and/or patterns may be the same or different depending on the desired properties and/or end use of the IGU. Combinations of coatings and surface patterns may also be used. In other embodiments, the third pane 130 may include at least one coating, and at least one of ink, surface features, and/or body features. Of course, such coatings, patterns and/or features may be similarly provided for the first and

second panes

110, 120.

Referring again to fig. 1, the third pane 130 and the outer pane 110 may be spaced apart and may define a first interstitial space 115 therebetween, and the third pane 130 and the second pane 120 may be spaced apart and may define a second interstitial space 125 therebetween. Both

interstitial spaces

115, 125 may be hermetically sealed by a sealant assembly 118, which sealant assembly 118 may be unitary or two parts, and if two parts, the same or different parts may be used. The example sealant assembly may be formed from a polymer-based sealant or other sealing material (e.g., silicone rubber). The

interstitial spaces

115, 125 may be filled with an inert gas. Suitable inert glasses include, but are not limited to: argon, krypton, xenon, and combinations thereof. Mixtures of inert gases or mixtures of one or more inert gases with air may also be used. Exemplary non-limiting inert gas mixtures include: argon/air, 95/5 krypton/air, or 22/66/12 argon/krypton/air mixtures in the ratios 90/10 or 95/5. Other ratios of inert gas or inert gas to air may also be used depending on the desired thermal performance and/or end use of the IGU. According to various embodiments, the gas used to fill the

interstitial spaces

115, 125 may be the same or different.

The gas pressure in the first interstitial space 115 and the second interstitial space 125 may be the same or different. The gas pressure difference may be due to, for example, a difference in average gas temperatures in the two spaces, e.g., depending on relative ambient or internal temperatures, the gas in the first interstitial space 115 may be warmer than the gas in the second interstitial space 125, or vice versa. The pressure differential between the two

interstitial spaces

115, 125 may be sufficient to cause the third pane 130 to bend or bow (depending on the thickness of the layer). To prevent bowing, in some embodiments, at least one channel or opening may be provided in the third pane 130 to allow gas in the interstitial space 115 to come into contact with gas in the interstitial space 125. The aperture may be provided by, for example, drilling one or more apertures or holes in the third pane 130, or providing a pressure relief path or channel through the sealant fitting 118, 128.

Referring now to fig. 3, an alternative IGU 1101 is shown that includes four

panes

110, 120, 130, 140. The illustrated embodiment is similar to fig. 1 and 2, except that the IGU 1101 includes an additional fourth (center) pane 140. The

center pane

130, 140 is disposed between the first and

second panes

110, 120.

In a non-limiting embodiment, the fourth pane 140 may be thinner than the first and

second panes

110, 120. In some embodiments, the fourth pane 140 may be thinner than the first and

second panes

110, 120.

In some embodiments, the fourth pane 140 may have a total thickness of less than about 2mm, for example: from about 0.8mm to less than about 2mm, or from about 0.9mm to less than about 1.8mm, or from about 1mm to less than about 1.7mm, or from about 1.1mm to less than about 1.6mm, or even less than about 1.6mm or even less than about 1.5, about 1.4, about 1.2 or about 0.9mm, including all ranges and subranges therebetween. According to other aspects, the thickness of the fourth pane 140 is greater than about 0.4mm, or greater than about 0.5 mm. In some embodiments, the fourth pane 140 may be a glass laminate including first and

second glass sheets

141, 142 and an intermediate polymer film or interlayer 143. The thickness of the fourth pane 140 may be the same as or different from the thickness of the third pane 130.

In a non-limiting embodiment, the fourth pane 140 may comprise a boroaluminosilicate glass, such as: alkaline earth boroaluminosilicate glasses are either alkali-free boroaluminosilicate glasses or other similar glass types. Exemplary commercial glass products include, but are not limited to: kang ning EAGLE

And

and (3) glass. According to various embodiments, the fourth pane 140 may be strengthened to improve the mechanical strength of the layer by, for example, thermal tempering, chemical strengthening, or other similar processes. In some embodiments, the fourth pane 140 may be produced by a float or fusion draw fabrication process. The composition of the fourth pane 140 may be the same as or different from the composition of the third pane 130. Similarly, the mechanical properties (e.g., degree of reinforcement) of the fourth pane 140 may be similar to the mechanical properties of the third pane 130The same or different.

According to various embodiments, the fourth pane 140 may have a lower CTE than the CTE of the first and/or

second panes

110, 120. In some embodiments, the CTE (CTE) of the fourth pane₄) May be less than about 70x10^-7/° c, for example: less than about 60x10^-7/° c, or less than about 50x10^-7/° c, or less than about 45x10^-7/° c, or less than about 40x10^-7/° c, or less than about 35x10^-7/° c, or less than about 30x10^-7/° c, or less than about 25x10^-7/° c, including all ranges and subranges therebetween, e.g., about 10x10^-7/° c to about 70x10^-7V. C. In other embodiments, the CTE of the first pane (CTE)₁) And/or the CTE (CTE) of the second pane₂) May be greater than the CTE (CTE) of the fourth pane₄) For example: CTE (coefficient of thermal expansion)₁>CTE₄And/or CTE₂>CTE₄Or CTE of₁≥2*CTE₄And/or CTE₂≥2*CTE₄Or CTE of₁≥2.5*CTE₄And/or CTE₂≥2.5*CTE₄Or CTE of₁≥3*CTE₄And/or CTE₂≥3*CTE₄。CTE₃And CTE₄May be the same or different. According to a non-limiting embodiment, CTE₃May be substantially equal to CTE₄。

Although not shown in fig. 3, one or both

major surfaces

134, 137 of the third pane 130 and/or one or more major surfaces (144, 147) of the fourth pane 140 can be partially or completely coated with at least one coating, such as coating 146, which can be a low emissivity coating as shown on major surface 144 of the fourth pane 140. Alternatively or additionally, one or both major surfaces of the third pane 130 and/or the fourth pane 140 may be partially or fully patterned with ink and/or surface features (e.g., decorative ink, light scattering ink, and/or light scattering surface features). Bulk scattering features below the surface within the glass matrix may also be provided in the third and/or

fourth panes

130, 140 by, for example, laser patterning. Laser patterning can also be used to create surface scattering features. The coatings and/or surface patterns on one or both major surfaces of the third and/or

fourth panes

130, 140 can be the same or different depending on the desired properties and/or end use of the IGU. Combinations of coatings and surface patterns may also be used. In other embodiments, the third and/or

fourth pane

130, 140 may include at least one coating and at least one of ink, surface features, and/or body features.

The third pane 130 may be spaced apart from the first pane 110 (e.g., the outer pane) and may define a first interstitial space 115 therebetween, the third pane 130 may be spaced apart from the fourth pane 140 and may define a second interstitial space 125 therebetween, and the fourth pane 140 may be spaced apart from the second pane 120 (e.g., the inner pane) and may define a third interstitial space 135 therebetween. The

interstitial spaces

115, 125, 135 may be hermetically sealed by

sealant assemblies

118, 128, 138, which may be of one construction or multiple pieces, each of the same or at least one different from the others. Exemplary sealant assemblies are disclosed above, and exemplary inert gases and inert gas mixtures for filling the interstitial spaces are disclosed above with respect to fig. 1. According to various embodiments, the gas used to fill the

interstitial spaces

115, 125, 135 may be the same or different.

Referring to fig. 1-3, the thickness of the

gap spaces

115, 125, 135 may vary depending on the IGU configuration and may range, for example, from about 6mm to about 18mm, for example: from about 7mm to about 16mm, alternatively from about 8mm to about 14mm, alternatively from about 10mm to about 12mm, including all ranges and subranges therebetween. The thickness of the interstitial spaces 115, 125 (fig. 2) or 115, 125, 135 (fig. 3) may be the same or different. The total thickness of

IGU

1000 or 1100 may be about 40mm or less, for example: about 36mm or less, or about 32mm or less, or about 30mm or less, or about 28mm or less, or about 26mm or less, including all ranges and subranges therebetween. In some embodiments, low U values (indicative of improved thermal insulation) may be obtained when the interstitial space thickness ranges from about 14mm to about 16mm and the total thickness of

IGU

1000 or 1100 ranges from about 36mm to about 40 mm. The overall thickness of IGU 1101 may be about 60mm or less, for example: about 56mm or less, or about 54mm or less, or about 50mm or less, or about 40mm or less, or about 30mm or less, or about 26mm or less, including all ranges and subranges therebetween. In some embodiments, low U values (indicative of improved thermal insulation) may be obtained when the interstitial space thickness ranges from about 16mm to about 18mm and the total thickness of IGU 1101 ranges from about 54mm to about 60 mm.

It should be noted that although the first and

second panes

110, 120 of fig. 1 and 2 are shown as a single glass sheet, the claims appended hereto should not be so limited as the panes may comprise a glass laminate structure, such as the

panes

110, 120 shown in fig. 3. Suitable glass-polymer laminate structures may include a single glass sheet laminated to a polymer film, or two glass sheets with an intermediate polymer film as shown, and the like. In some embodiments, the laminate may comprise two or more panes, for example three or more panes, selected from: alkaline earth boro-aluminosilicate glasses, alkali-free boro-aluminosilicate glasses, and soda-lime-silicate glasses.

According to other aspects of the present disclosure, first pane 110 includes a first polymer interlayer between the first glass sheet and the second glass sheet, wherein the first polymer interlayer is bonded to the first glass sheet and the second glass sheet. In some embodiments, the first polymer interlayer comprises a first polymer having a first modulus of elasticity and a second polymer having a second modulus of elasticity, and wherein the first modulus of elasticity exceeds the second modulus of elasticity by a factor of at least about 20 or more. Similarly, according to other aspects, second pane 120 comprises third and fourth glass sheets and a second polymer interlayer between the third and fourth glass sheets, wherein the second polymer interlayer is bonded to the third and fourth glass sheets. In some embodiments, the second polymer interlayer comprises the first polymer and the second polymer. Similarly, according to other additional aspects, the third pane 130 also includes fifth and

sixth glass sheets

131, 132 and a third polymer interlayer 133 between the fifth and

sixth glass sheets

131, 132, the third polymer interlayer 133 being bonded to the fifth and

sixth glass sheets

131, 132. In some embodiments, the third polymer interlayer 133 includes the first polymer and the second polymer. The polymer interlayer with the first and second polymers helps to reduce acoustic penetration.

The IGUs disclosed herein may be used in a variety of applications and configured into products including, by way of non-limiting example: windows, doors, and skylights in building and other architectural applications, as windows in automotive and other vehicle applications, as windows or display panels in appliances, and display panels in electronic devices, among others. According to various embodiments, one or more LEDs may be optically coupled to at least one edge of the IGU to provide illumination on one or more areas of the IGU. Edge lighting can provide, for example, illumination that simulates daylight, which can be useful for various architectural and automotive applications (e.g., skylights and sun roof windows). As described above, one or more panes in an IGU may be provided with body or surface light scattering features, which may promote uniformity of light penetration by the IGU. In some embodiments, low CTE glasses may be easier to produce such light scattering features by laser processing than higher CTE glasses that often crack or build up other defects during laser patterning.

In various non-limiting embodiments, employing a thin, low CTE laminated glass for the center pane(s), e.g., the third and/or fourth panes, may provide several advantages over conventional IGUs. For example, a low CTE center pane may improve resistance to thermal stress and/or cracking due to temperature gradients on the IGU without the need for chemical or thermal strengthening. Thus, manufacturing costs can be reduced by eliminating the thermal tempering or chemical strengthening steps that would otherwise be used to strengthen a center pane comprising conventional glass having a higher CTE.

Furthermore, using a laminated center pane as the center pane rather than a single sheet of glass can simplify the physical handling requirements and manufacturing handling requirements of the thin center pane. Thus, in some embodiments of the present disclosure, the center pane may comprise a sheet as thin as about 0.4 to about 0.7mm, such that the laminated pane as a whole is still significantly thinner than even the thinnest conventional center pane. The use of a laminated center pane with a polymeric interlayer (particularly an optional acoustic PVB polymer layer) improves sound attenuation, which can help offset the reduction in sound attenuation due to the reduced mass of the center pane.

The use of low CTE glass also enables thinner panes to be provided with low E coatings on one or both surfaces in an economical manner. Without the low CTE glass, strengthening would be required to survive the center pane location, and strengthening at <0.9mm is difficult or not feasible with conventional techniques. Furthermore, chemical strengthening is economically impractical because it is incompatible with large pre-coated low E sheets that are later cut to size, so the use of low CTE glasses enables thin low E coated sheets and panes containing them to be achieved by the techniques herein described and claimed.

Referring to fig. 4, in some aspects of the present disclosure, a method of manufacturing an

IGU

1000, 1100, 1101 is provided (illustrated in fig. 4 as method 1102). The method 1102 includes cutting a glass sheet 130 of a selected size from a larger glass sheet 150, for example, as shown in phantom. The larger glass sheet 150 has a low emissivity coating 156 on its first major surface 154 and optionally on its second major surface 158. The larger glass sheet 150 may have a temperature range of less than about 70x10 over a temperature range of 0 to about 300 deg.C^-7CTE per degree C. The larger glass sheet may have the following thickness: less than about 2mm, or even less than about 1.5, or less than about 1.4, or less than about 1.2, or less than about 0.9 mm. According to other aspects, the thickness of the third pane 130 is greater than about 0.4mm, or greater than about 0.5 mm. The method further comprises the following steps: the glass sheet 130 is assembled with the first pane 110 and the second pane 120 (e.g., IGU 1000 or 1100) or with the first pane 110, the second pane 120, and the fourth pane 140 (e.g., IGU 1101) as the third pane 130 or as a component of the third pane 130. The third pane 130 is assembled to be positioned in the first paneBetween the pane 110 and the second pane 120, such that the first sealed interstitial space 115 is located on one side of the third pane 130 and the second sealed interstitial space 125 is located on the other side of the third pane 130. The larger glass sheet 150 may desirably have an even lower Coefficient of Thermal Expansion (CTE), less than about 50x10, over a temperature range of 0 to about 300 c^-7/deg.C or less than about 35x10^-7V. C. The larger glass sheet 150 may also have a thickness of less than about 0.8mm or less than about 0.6 mm. In other aspects, the larger glass sheet 150 may desirably have a thickness of greater than about 0.4mm, or greater than about 0.5 mm.

According to another embodiment, a method of producing an IGU having a thin laminated center pane is shown in fig. 4. The illustrated IGU (insulated glass unit) manufacturing method 1102 includes cutting a selected size third pane 130 from the laminated sheet 150, as shown in phantom in the figure. The laminated sheet 150 includes first and second glass sheets 151, 152 laminated together by a polymer interlayer 153, the first and second glass sheets having a temperature range of from 0 to about 300 ℃ of less than about 70x10^-7A CTE per deg.c and a thickness of less than about 0.9 mm. The method further comprises the following steps: the third pane 130 is assembled with the first and

second panes

110, 120, or with the first, second and

fourth panes

110, 120, 140, thereby forming an insulating

glass unit

1100, 1101 with the third pane positioned between the first and second panes, with a first sealed interstitial space 115 on one side of the third pane and a second sealed interstitial space 125 on the other side of the third pane. The thickness of the laminated sheet as a whole may be greater than about 0.8mm, thereby achieving a thickness of the

individual sheets

131, 132 of about 0.4mm or greater, thereby facilitating handling during the lamination process. The laminated sheet 150 may have length and width dimensions of at least greater than about 1.3 by about 1.3m, desirably greater than about 2 by about 2 m. In another optional embodiment variation, at least one of the

major surfaces

154, 158 of the laminated sheet may be coated with at least one coating 156, such as a low emissivity coating.

Since thermal tempering of the center pane can be avoided, the optical performance of the IGU can be improved, for example, because it does not contain warpage or birefringence due to such processing steps. The absence of a thermal tempering step may also enable a thinner center pane, resulting in a reduction in the overall thickness and/or weight of the IGU. Reducing IGU weight can result in cost savings during manufacturing, transportation, installation, maintenance, and/or operation. Reducing the IGU thickness may extend the range of applications for IGUs that may otherwise be limited by conventional design constraints.

A thinner low CTE center layer may also enable a wider sealed interstitial space between the panes. Sealing a larger volume of insulating gas in the interstitial space may improve the energy efficiency of the IGU. IGUs with narrow sealed gap spaces have an increased risk of bowing due to gas compression within the gap spaces, which can result in contact between the outer and center panes. Such contact is aesthetically undesirable and also allows for direct heat conduction between the panes, which is unacceptable from an energy standpoint. The use of a thinner low CTE center pane may provide a wider gap and thus reduce the potential risk of bowing and/or contact between panes.

Thermal stresses that cause glass in an IGU to crack may be due to, for example, rapid temperature changes in one region of the IGU relative to another region of the IGU. For example, a rapid rise in external (ambient) temperature relative to internal temperature (or vice versa) may create thermal stress on one or more regions of the IGU. For example, on a cold morning, sunlight shining onto the window may cause the temperature of the area of the IGU exposed to the sunlight to rise rapidly while the perimeter of the IGU (e.g., disposed below the window frame) remains cold. Finite Element Analysis (FEA) modeling shows that for conventional soda-lime-silicate glasses, the resulting thermal stress on the center pane reaches a temperature difference of about 0.62 MPa/c. Alternatively, under summer conditions (e.g., about 28 ℃), the center pane may reach temperatures up to about 60 ℃, resulting in temperature differences between the center pane and the outer pane of up to about 40 ℃. Thus, as a result, the thermal stress on the center layer comprising the soda-lime-silicate glass may be about 25MPa or greater.

The soda-lime-silicate glass had a thickness of about 90x10^-7CTE per degree C. However, in comparison, however,

EAGLE

the CTE of the glass was 31.7x10^-7/° c, about 1/3 for the CTE of soda-lime-silicate glass. EAGLE is included under the same 40 ℃ thermal gradient described above

The central layer of glass may be subjected to a thermal stress of 8.7MPa, resulting in a lower risk of breakage, even in the absence of thermal tempering or chemical strengthening.

Modeling was used to evaluate the use of low CTE glass as a center pane between two higher CTE panes in an IGU. The model assumes a three-layer IGU (length 1265mm and width 989mm), an outer pane comprising soda-lime-silicate glass (thickness 4mm), an inner pane comprising soda-lime-silicate glass (thickness 6mm), and a center pane comprising EAGLE

Glass (thickness 0.7 mm). The gap width between the center pane and the inner and outer panes was 12mm, filled with argon, and sealed by a silicone rubber perimeter sealant.

Referring to FIG. 5, a third pane of tensile stress low CTE glass (with Corning EAGLE)

As a low CTE glass) was modeled at +60 ℃ to simulate the scenario where the soda-lime-silicate pane expanded due to temperature elevation. FIG. 6 is EAGLE at-40 deg.C

A compressive stress model on the center pane, simulating a scene where the soda-lime-silicate pane shrinks due to a decrease in temperature. FIG. 5 shows EAGLE at +60 deg.C

Maximum principal stress on the center pane is less than 1MPa, and FIG. 6 shows EAGLE

Deflection of the center pane is below 1mm, indicating that the model (three-pane) IGU can suitably withstand cracking, warping, and/or distortion due to thermal stress induced by both high and low temperature gradients.

FIG. 7 is a calculated deflection (sag) as a function of thickness for a glass sheet processed on a roller bed conveyor having a typical roller spacing, such as used in glass transfer in low E coating processes, for an exemplary process. As can be seen from the figures, there is a significant sag difference where about 0.5mm or about 0.4mm starts and is thinner. Accordingly, it is desirable that the thickness of the larger sheet 150 and the sheets 130 cut therefrom be at least about 0.4mm or greater, or even about 0.5mm or greater.

FIG. 8 is a graph of calculated deflection and stress as a function of sheet thickness for a glass sheet having a limit on the thermal gradient across the thickness at its edge that may exist, for example, in a window under certain weather conditions. Similarly, for the deflection shown in FIG. 7, a significant difference in thermally induced deflection occurs at about 0.5mm or at and below about 0.4 mm. Also for this reason, it is desirable that the thickness of the larger sheet 150 and the sheets 130 cut therefrom be at least about 0.4mm or greater, or even about 0.5mm or greater.

It will be understood that the various embodiments disclosed may be directed to specific features, elements, or steps described in connection with particular embodiments. It will also be understood that although specific features, elements or steps are described in connection with one particular embodiment, the various embodiments may be interchanged or combined in various combinations or permutations not shown.

It is also to be understood that the terms "the", "a" or "an", as used herein, mean "at least one" and should not be limited to "only one" unless explicitly stated to the contrary. Thus, for example, reference to "a component" includes instances having one such component or two or more such components, unless the context clearly indicates otherwise. Similarly, "plurality" or "array" is intended to mean two or more, and thus "array of components" or "plurality of components" means two or more such components.

Ranges can be expressed herein as from "about" another particular value, and/or to the end of a range. When such a range is expressed, examples include from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

All numerical values set forth herein are to be construed as including "about" unless clearly indicated to the contrary. However, it is also to be understood that each numerical value recited is an exact estimate, whether or not it is expressed as "about" the particular numerical value. Thus, "less than 100nm in size" and "less than about 100nm in size" both include embodiments where "less than about 100nm in size" and "less than 100nm in size".

Unless expressly stated otherwise, it is not intended that any method described herein be construed as requiring that its steps be performed in a particular order. Thus, where a method claim does not actually recite an order to be followed by its steps or it does not otherwise specifically imply that the steps are to be limited to a specific order in the claims or specification, it is not intended that any particular order be implied.

Although the transition term "comprising" may be used to disclose various features, elements or steps of a particular embodiment, it should be understood that this implies that alternative embodiments may be included which may be described using the transition term "consisting of. Thus, for example, implied alternative embodiments to a device comprising a + B + C include embodiments where the device consists of a + B + C and embodiments where the device consists essentially of a + B + C.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope and spirit of the disclosure. Since numerous modifications, combinations, sub-combinations and variations of the described embodiments incorporating the spirit and substance of the disclosure may occur to persons skilled in the art, it is intended that the disclosure herein include all such equivalents as fall within the scope of the appended claims.

Claims

1. An insulating glass unit (1100), comprising:

a first pane (110);

a second pane (120);

a third pane (130) disposed between the first pane and the second pane;

a first sealed interstitial space (125) defined between the first pane and the third pane; and

a second sealed interstitial space (115) defined between the second pane and the third pane;

wherein the third pane comprises a first glass sheet (131) having less than about 70x10 over a temperature range of 0 to about 300 ℃^-7Coefficient of Thermal Expansion (CTE) of/° C.

2. The insulated glass unit of claim 1, wherein the third pane further comprises a second glass sheet (132) laminated to the first glass sheet (131) by a polymer interlayer (133), the second glass sheet having less than about 70x10 over a temperature range of 0 to about 300 ℃^-7Coefficient of Thermal Expansion (CTE) of/° C.

3. The insulating glass unit as in claim 1 or 2, wherein one or both of the first and second glass sheets has a temperature in the range of 0 to about 300 ℃ of less than about 50x10^-7Coefficient of Thermal Expansion (CTE) of/° C.

4. The insulating glass unit as in claim 1 or 2, wherein one or both of the first and second glass sheets has a temperature in the range of 0 to about 300 ℃ of less than about 35x10^-7Coefficient of Thermal Expansion (CTE) of/° C.

5. The insulating glass unit as in any of the preceding claims, wherein the third pane comprises a boroaluminosilicate glass.

6. The insulating glass unit as in claim 5, wherein the third pane comprises an alkaline earth boroaluminosilicate glass or a non-alkali boroaluminosilicate glass.

7. The insulated glass unit of any of the preceding claims, wherein the third pane comprises float formed glass.

8. The insulated glass unit of any of the preceding claims, wherein the third pane has a thickness of less than about 1.6 mm.

9. The insulated glass unit of any of the preceding claims, wherein the third pane has a thickness of less than about 0.9 mm.

10. The insulated glass unit of any of the preceding claims, wherein at least one of the inner surface (114) of the first pane, the inner surface (124) of the second pane, or the at least one major surface (134, 137) of the third pane is coated with at least one layer of a low emissivity coating (116, 117, 136).

11. The insulated glass unit of claim 10, wherein at least one major surface of the third pane is coated with at least one low emissivity coating (136).

12. An insulated glass unit (1101) comprising:

a first pane (110);

a second pane (120);

a third pane (130); and

a fourth pane (140) disposed between the first pane and the second pane;

a first sealed interstitial space (115) defined between the first pane and the third pane; and

a second sealed interstitial space (125) defined between the third pane and the fourth pane;

a third sealed interstitial space (135) defined between the second pane and the fourth pane;

13. The insulated glass unit of claim 12, wherein the third pane further comprises a second glass sheet (132) laminated to the first glass sheet (131) by a polymer interlayer (133), the second glass sheet having less than about 70x10 over a temperature range of 0 to about 300 ℃^-7Coefficient of Thermal Expansion (CTE) of/° C.

14. The insulated glass unit (1200) of claim 13, wherein the fourth pane comprises a first glass sheet (141) and a second glass sheet (142) laminated together by a polymer interlayer (143), the first glass sheet and the second glass sheet having less than about 70x10 over a temperature range of 0 to about 300 ℃^-7Coefficient of Thermal Expansion (CTE) of/° C.

15. The insulated glass unit of claim 14, wherein the first and second glass sheets of the third pane and the first and second glass sheets of the fourth pane each have a temperature of less than about 35x10 over a temperature range of 0 to about 300 ℃^-7Coefficient of Thermal Expansion (CTE) of/° C.

16. The insulated glass unit of claim 15, wherein the third pane and the fourth pane each have a thickness of less than about 1.6 mm.

17. A method (1102) of manufacturing an insulating glass unit, the method comprising the steps of:

cutting a glass sheet (130) of selected dimensions from a larger glass sheet (150) having a first major surface (151) and a second major surface (152), the larger glass sheet (150) having less than about 70x10 over a temperature range of 0 to about 300 ℃^-7A Coefficient of Thermal Expansion (CTE) of/° C and a thickness of less than about 0.9 mm;

assembling the glass sheet with a first pane (110) and a second pane (120), or with a first pane (110), a second pane (120), and a fourth pane (140), as a third pane (130) or an assembly of the third pane (130), thereby forming an insulating glass unit (1000, 1100, 1101), the third pane (130) being located between the first pane (110) and the second pane (120), there being a first sealed interstitial space (115) on one side of the third pane (130), and a second sealed interstitial space (125) on the other side of the third pane (130).

18. The method of claim 17, wherein the larger glass sheet (150) has less than about 50x10 over a temperature range of 0 to about 300 ℃⁷Coefficient of Thermal Expansion (CTE) of/° C.

19. The method of claim 17, wherein the larger glass sheet (150) has less than about 35x10 over a temperature range of 0 to about 300 ℃⁷Coefficient of Thermal Expansion (CTE) of/° C.

20. The method of any of claims 17-19, wherein the larger glass sheet (150) has a thickness of less than about 0.8 mm.

21. The method of any of claims 17-19, wherein the larger glass sheet (150) has a thickness greater than about 0.4 mm.

22. The method of claim 17, wherein the larger glass sheet is a laminate sheet comprising a first glass sheet (151) and a second glass sheet (151, 152) laminated together by a polymer interlayer (153).

23. The method of any of claims 17-22, wherein the third pane has a thickness greater than about 0.8 mm.

24. The method of claim 23 wherein the laminate has length and width dimensions greater than about 1.3 by about 1.3 m.

25. The method of any one of claims 17-24, wherein at least one of the major surfaces of the larger sheet is coated with at least one layer of a low emissivity coating (156).

26. The method of claim 17, wherein the assembling step further comprises providing a building product.