Wedge-shaped multilayer intermediate layer with outer skin layers of varying thicknesses

Abstract

A multilayer intermediate layer having enhanced optical and acoustic properties is provided along with a method for manufacturing and using the same. The intermediate layer described herein may comprise two or more outer skin layers and an inner core layer, wherein one of the outer skin layers has a thickness different from the remaining outer skin layers at one or more locations along the intermediate layer. The multilayer intermediate layer may also exhibit acoustic properties and, in some cases, may have a full wedge-shaped thickness profile. Additionally, in some embodiments, the intermediate layer and the laminate formed therefrom may also provide reduced infrared energy transmittance without sacrificing acoustic and / or optical performance.

Description

Technology Field

[0001] The present invention relates to a polymeric intermediate layer as well as a method for manufacturing and using the same. The intermediate layer can be used to form a multilayer panel (e.g., a windshield or window) having desirable characteristics. Background Technology

[0002] Poly(vinyl butyral) (PVB) is commonly used in the manufacture of polymer sheets that can be used as an interlayer in light-transmitting laminates (e.g., safety glass or polymeric laminates). Safety glass commonly refers to a transparent laminate containing a poly(vinyl butyral) sheet or interlayer placed between two sheets of glass. Safety glass is commonly used in automotive and architectural applications. Its primary function is to minimize damage or injury to objects or people near the glass by absorbing energy (e.g., caused by impact from an object) without scattering glass fragments or penetrating through the opening. Safety glass can also be used to provide other beneficial effects, such as reducing ultraviolet (UV) and / or infrared (IR) light transmission or improving the appearance and aesthetic appeal of window openings.

[0003] Safety glass interlayers have also been used as an important component of automotive head-up display (HUD) systems, which can provide images (e.g., instrument panel images) at the driver's eye level. These displays allow the driver to focus on the approaching road while visually accessing dashboard information. One type of interlayer used in these head-up display systems has a wedge-shaped vertical cross-section. Wedge-shaped interlayers are used to provide accurate light dynamics through the windshield required for the head-up display. Unfortunately, just as with standard windshields, head-up display windshields can also cause undesirable high levels of noise transmission through the windshield.

[0004] To address noise transmission, a multilayer intermediate layer comprising one or more acoustic or noise-attenuating polymer layers was used. The acoustic layer may have physical and / or chemical properties different from the surrounding layer, which may contribute to undesirable optical properties (e.g., turbidity or spots).

[0005] Additionally, some intermediate layers contain infrared-absorbing compounds to control the amount of energy passing into the vehicle's cabin through windows or windshields. One example of an infrared-absorbing compound is infrared-absorbing particles that can be dispersed throughout the intermediate layer. High concentrations of infrared-absorbing particles can block the transmission of a specific wavelength range of infrared energy from, for example, external traffic sensors or even on-board sensors, such as a rain sensor operating in the wavelength range of about 850 nm to about 1050 nm. On the other hand, low concentrations of infrared-absorbing particles may not block a sufficient amount of radiation, which results in unwanted heating within the vehicle cabin due to infrared transmission.

[0006] Therefore, there is a need for improved compositions and methods to maintain both the noise attenuation characteristics and visual features of multilayer glass panels, in particular, for multilayer glass panels in which a wedge-shaped intermediate layer is used to provide a head-up display function. It would be advantageous for the intermediate layer to provide sufficient infrared-absorbing characteristics while maintaining desirable strength and noise attenuation characteristics.

[0007] In one embodiment, the present invention relates to a wedge-shaped multilayer intermediate layer comprising a wedge-shaped first polymer layer; a wedge-shaped second polymer layer; and a third polymer layer between the first layer and the second layer, wherein each of the first and second layers has a glass transition temperature (T) of the third layer g T at least 10℃ higher than ) gThe second layer is at least 10% thicker than the first layer at one or more locations on the intermediate layer, and at least one of the first and second layers has a thickness of 0.30 mm or less at one or more locations on the intermediate layer.

[0008] In another aspect, the present invention relates to a multilayer intermediate layer comprising first, second, and third polymer layers, wherein the third layer is located between the first and second layers, and each of the first and second layers is the T of the third layer g T at least 10℃ higher than g The structure has, at one or more locations on the intermediate layer, the first layer has a thickness of less than 0.3 mm and the second layer has a thickness of greater than 0.3 mm, and at least one of the following criteria (i) to (iii) is satisfied: (i) at one or more locations on the intermediate layer, the thickness of the first layer is 0.2 mm or more; (ii) at one or more locations on the intermediate layer, the ratio of the thickness of the second layer to the thickness of the first layer is 2.5 or less:1; and (iii) the maximum value of the difference in polyvinyl acetate content between any two of the first, second, and third polymer layers is 13 weight% or less.

[0009] In another aspect, the present invention relates to a wedge-shaped multilayer intermediate layer comprising a first wedge-shaped polymeric outer layer, a second wedge-shaped polymeric outer layer, and a polymeric core layer interposed between the first and second outer layers, wherein each of the outer layers is T of the core layer g T at least 10℃ higher than g The intermediate layer has a total wedge angle of 0.05 mrad or more and 1 mrad or less, the intermediate layer has a thinnest edge and a thickest edge, and the maximum thickness of at least one of the first and second outer layers does not exceed 0.3 mm within 40 cm of the thinnest edge.

[0010] In another aspect, the present invention relates to a wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers, wherein the third layer is located between the first and second layers, and the first and second layers are each T of the third layer g T at least 10℃ higher than g Having, the first layer has a thickness profile defined by the following formula:

[0011] [0.0024( D e ) + 0.06] < T 1 < [1.975141 - (1.6936517) / (1 + ( D e / 155.2664)^3.324064)]

[0012] In the above formula,

[0013] D e is the distance (cm) from the thinnest edge of the intermediate layer, and

[0014] T 1 silver D e It is the thickness (mm) of the first layer.

[0015] In another aspect, the present invention relates to a multilayer plate glass comprising a first rigid substrate, a second rigid substrate, and an intermediate layer interposed between the first substrate and the second substrate, wherein the intermediate layer is the intermediate layer described in any previously mentioned paragraph.

[0016] In another aspect, the present invention relates to a method for manufacturing a multilayer intermediate layer, the method comprising: (a) providing a skin resin; (b) providing a core resin having a composition different from that of the skin resin; (c) forming a first skin layer from a portion of the skin resin and forming a second skin layer from another portion of the skin resin, wherein the forming comprises supplying the resin used to form the first skin layer to a die at a material flow rate different from that of the skin resin used to form the second skin polymer layer; (d) forming a core layer from at least a portion of the core resin; and (e) forming a multilayer polymer layer from the first skin layer, the second skin layer, and the core layer, wherein in one or more portions of the multilayer polymer layer, the first skin layer is at least 10% thicker than the second skin layer.

[0017] In another embodiment, a wedge-shaped multilayer intermediate layer is provided, comprising a first polymer layer having a wedge shape, a second polymer layer, and a third polymer layer between the first layer and the second layer, wherein the first and second layers each have a glass transition temperature (T) of the third layer. g T at least 10℃ higher than ) g The intermediate layer comprises a tapered band having a thinnest edge and a thickest edge, and the thickness of the first polymer layer at the thinnest edge of the tapered band is greater than the thickness of the first polymer layer at the thickest edge of the tapered band.

[0018] In another embodiment, one example is generally illustrated in FIG. 13, and a wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers is provided, wherein the third layer is located between the first and second layers, and at least one of the first and second layers is wedge-shaped. The intermediate layer has a tapered region having a thinnest edge and a thickest edge, and at all points along a vertical centerline extending between the thinnest edge and the thickest edge, the following relationship is satisfied:

[0019] 1.25Tca > TcL > 0.75Tca

[0020] In the above formula,

[0021] TcL is the local total thickness of the first and second layers, and

[0022] Tca is the average total thickness of the first and second layers calculated as follows:

[0023] Tca = (Tc1 + Tc2) / 2,

[0024] At this time, Tc1 is the total thickness of the first and second layers at the thinnest edge, and Tc2 is the total thickness of the first and second layers at the thickest edge.

[0025] In some embodiments, for example, as shown in FIG. 13, the thickness of the first layer at the thinnest edge (shown as T1s1) and the thickness of the second layer at the thinnest edge (shown as T2s1) are combined to provide Tc1, and the thickness of the first layer at the thickest edge (shown as T1s2) and the thickness of the second layer at the thickest edge (shown as T2s2) are combined to provide Tc2.

[0026] In another embodiment, a wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers is provided, wherein the third layer is located between the first layer and the second layer, and at least one of the first and second layers is wedge-shaped. The intermediate layer comprises a tapered band having a thinnest edge and a thickest edge, the first layer has a thickness that increases from the thinnest edge to the thickest edge of the tapered band, the second layer has a thickness that decreases from the thinnest edge to the thickest edge of the tapered band, and at least one of the first, second, and third layers comprises one or more IR absorbers.

[0027] In another embodiment, a wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers is provided, wherein the third layer is located between the first and second layers, and at least one of the first and second layers is wedge-shaped. The intermediate layer has a tapered band having a thinnest edge and a thickest edge, the total wedge angle is greater than or equal to 0.30 mrad, and the total solar transmittance (%Tts) measured at the thickest edge of the tapered band is within about 5% of the total solar transmittance measured at the thinnest edge of the tapered band. At least one of the first, second, and third polymer layers comprises an IR absorber, and each of the layers comprising the IR absorber is formed from the same polymer material at both the thinnest edge and the thickest edge of the tapered band. Brief explanation of the drawing

[0028] Various embodiments of the present invention are described in detail below with reference to the accompanying drawings. FIG. 1a is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, particularly illustrating specific dimensions of the intermediate layer. FIG. 1b is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, particularly illustrating a wedge angle measurement. FIG. 1c is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, in particular, illustrating an intermediate layer having a tapered band located between a plurality of flat bands. FIG. 2 is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, particularly illustrating an intermediate layer having more than three polymer layers. FIG. 3 is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates one example of an intermediate layer having skin layers of different thicknesses. FIG. 4 is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates another example of an intermediate layer of different thicknesses. FIG. 5 is a vertical cross-sectional view of an intermediate layer according to an embodiment of the present invention, particularly illustrating one example of an intermediate layer having skin layers of different thicknesses. FIG. 6 is a schematic diagram of an intermediate layer according to an embodiment of the present invention, particularly illustrating specific dimensions of the intermediate layer. FIG. 7 is a schematic diagram of a laminated windshield according to an embodiment of the present invention using an intermediate layer as exemplified in FIG. 6. FIG. 8 is a graph illustrating the thickness of the first, second, and third polymer layers and the total thickness of the intermediate layer according to an embodiment of the present invention, illustrated as a function of position. FIG. 9 is a graph illustrating the thickness range of the first layer of the intermediate layer according to an embodiment of the present invention, illustrated as a function of position. FIG. 10 is a cross-sectional view of the thickness of the comparative intermediate layer tested as described in Example 1. FIG. 11 is a cross-sectional view of the thickness of an intermediate layer according to an embodiment of the present invention, tested as described in Example 1. FIG. 12a is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates one example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 12b is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates another example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 12c is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates another example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 12d is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates another example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 12e is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates another example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 12f is a vertical cross-sectional view of a molded intermediate layer according to an embodiment of the present invention, illustrating another example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 12g is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, and in particular, illustrates another example of an intermediate layer having a skin layer having an inverted wedge configuration. FIG. 13 is a vertical cross-sectional view of a wedge-shaped intermediate layer according to an embodiment of the present invention, particularly illustrating the skin thickness combined along the vertical dimensions of the intermediate layer. Specific details for implementing the invention

[0029] A polymeric intermediate layer suitable for forming a laminate (e.g., windshields and other glass laminates) is described herein along with methods for manufacturing and using said intermediate layer. The intermediate layer described herein may comprise an acoustic intermediate layer having noise-attenuation properties. Additionally, in some cases, said intermediate layer may be wedge-shaped or tapered, and in other cases, said intermediate layer may be flat. Furthermore, the intermediate layer described herein also exhibits enhanced optical properties (e.g., spots), making it particularly suitable for automotive applications.

[0030] In this document, the terms “polymer resin composition” and “resin composition” refer to a composition comprising one or more polymer resins. The polymer composition may optionally include other components, such as plasticizers and / or other additives. In this document, the terms “polymer layer” and “polymeric layer” refer to one or more polymer resins formed into polymer sheets optionally combined with one or more plasticizers. In other words, the polymer layer may include additional additives, but this is not mandatory. In this document, the term “interlayer” refers to a single-layer or multilayer polymer sheet suitable for use with one or more rigid substrates to form a multilayer panel. The terms “single-sheet” interlayer and “monolithic” interlayer refer to an interlayer formed from a single resin sheet, and the terms “multilayer” and “multilayer” interlayer refer to an interlayer having two or more resin sheets that are co-extruded, bonded, or otherwise coupled to each other.

[0031] Now, returning to FIGS. 1 through 5, some embodiments of the intermediate layer (10) are illustrated. As illustrated in FIGS. 1 through 5, the intermediate layer (10) as described herein may comprise, for example, a multilayer intermediate layer having a first polymer layer (1), a second polymer layer (2), and a third polymer layer (3). In this document, terms “first,” “second,” “third,” etc. are used to describe various elements, but these elements should not be unnecessarily limited by such terms. Such terms are used merely to distinguish one element from another and do not necessarily imply a specific order or even a specific element. For example, one element may, without contradiction, be considered the “first” element in the specification and the “second” element in the claims. Consistency is maintained within the specification and for each independent claim, but such nomenclature is not necessarily intended to be consistent between them. One embodiment of an intermediate layer comprising a fourth layer (4) and a fifth layer (5) located between the first layer (1) and the third layer (3) and between the third layer (3) and the second layer (2), respectively, is illustrated in FIG. 2.

[0032] In some embodiments, the intermediate layer (10) may have an overall wedge-shaped or wedge-shaped profile. As used herein, the terms “wedge-shaped” or “wedge-shaped” mean having a cross-sectional geometry that increases from a relatively thin dimension to a relatively thick dimension in at least part. As illustrated in FIG. 1, the intermediate layer may include a tapered band (16) having a thinnest edge (14) and a thickest edge (12) located opposite it, in the case of a wedge-shaped layer, and may exhibit a non-uniform thickness profile between the thinnest edge (14) and the thickest edge (12). The wedge-shaped intermediate layer or layer may have a minimum wedge angle of 0.05 mrad or more.

[0033] In some embodiments, the thickest edge (12) of the tapered band (16) may have a total thickness of about 0.60 mm or more, about 0.65 mm or more, about 0.70 mm or more, about 0.75 mm or more, about 0.80 mm or more, about 0.85 mm or more, or about 0.90 mm or more and / or about 2.0 mm or less, about 1.95 mm or less, about 1.90 mm or less, about 1.85 mm or less, about 1.80 mm or less, about 1.75 mm or less, about 1.70 mm or less, about 1.65 mm or less, about 1.60 mm or less, about 1.55 mm or less, or about 1.50 mm or less (of all layers at that point).

[0034] The thinnest edge (14) of the tapered band (16) may have a total thickness of about 0.50 mm or more, about 0.55 mm or more, about 0.60 mm or more, about 0.65 mm or more, or about 0.70 mm or more, and / or about 1.1 mm or less, about 1.0 mm or less, about 0.95 mm or less, about 0.90 mm or less, about 0.85 mm or less, about 0.80 mm or less, about 0.75 mm or less, or about 0.70 mm or less (of all layers at that point).

[0035] In some embodiments, about 10% or more, about 20% or more, about 30% or more, about 40% or more, about 50% or more, about 60% or more, about 70% or more, about 80% or more, or about 90% or more of the total vertical cross-section of the intermediate layer (10) may be wedge-shaped or have non-uniform thickness. As used herein, the term “vertical cross-section” refers to a cross-section taken between the thickest edge (12) and the thinnest edge (14) of the wedge-shaped intermediate layer (10) (or tapered band (16)). FIGS. 1 through 4 illustrate various embodiments of the wedge-shaped intermediate layer (10) taken along each vertical cross-section. Additionally or alternatively, about 90% or less, about 80% or less, about 70% or less, about 60% or less, about 50% or less, about 40% or less, about 30% or less, or about 20% or less of the total vertical cross-section of the intermediate layer (10) may have non-uniform thickness. In other cases, the entire (100%) of the vertical cross-section may be wedge-shaped. For example, all vertical cross-sections of the intermediate layer illustrated in FIGS. 1 to 4 have a total vertical cross-section of non-uniform thickness.

[0036] In some embodiments, at least one of the edges of the tapered band (16) may be located at or near at least one of the edges of the intermediate layer itself (illustrated as the thickest edge (12) and the thinnest edge (14) in FIG. 1), and in other embodiments, the edges of the tapered band (16) may be spaced apart from at least one of the edges of the intermediate layer (10). In some cases, the ratio of the length of the tapered band (16) to the length of the intermediate layer (10) (measured between the thinnest edge (14) and the thickest edge (12) of the intermediate layer (10)) may be at least about 0.10:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, at least about 0.40:1, at least about 0.45:1, at least about 0.50:1, at least about 0.55:1, at least about 0.60:1, at least about 0.65:1, at least about 0.70:1, at least about 0.75:1, at least about 0.80:1, at least about 0.85:1, at least about 0.90:1, at least about 0.95:1, or at least about 0.99:1. there is.

[0037] Alternatively or additionally, the ratio of the length of the tapered band (16) to the length of the intermediate layer (10) may be about 0.99 or less:1, about 0.95 or less:1, about 0.90 or less:1, about 0.85 or less:1, about 0.80 or less:1, about 0.75 or less:1, about 0.70 or less:1, about 0.65 or less:1, about 0.60 or less:1, about 0.55 or less:1, about 0.50 or less:1, about 0.45 or less:1, about 0.40 or less:1, about 0.35 or less:1, about 0.30 or less:1, about 0.30 or less:1, about 0.25 or less:1, about 0.20 or less:1, about 0.15 or less:1, or about 0.10 or less:1.

[0038] In some embodiments, the tapered band (16) constitutes about 10% or more, about 15% or more, about 20% or more, about 25% or more, about 30% or more, about 35% or more, about 40% or more, about 45% or more, or about 50% or more and / or about 99% or less, about 95% or less, about 90% or less, about 85% or less, about 80% or less, about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, or about 50% or less. An example of an intermediate layer having a tapered band (16) smaller than the total width of the intermediate layer (10) is shown in FIG. 1c.

[0039] In some embodiments, the distance between the thinnest edge (14) and the thickest edge (12) of the intermediate layer (10) (or tapered band (16)) is about 50 cm or more, about 55 cm or more, about 60 cm or more, about 65 cm or more, about 70 cm or more, about 75 cm or more, about 80 cm or more, about 85 cm or more, about 90 cm or more, about 95 cm or more, about 100 cm or more, about 110 cm or more, about 120 cm or more, about 130 cm or more, about 140 cm or more, about 150 cm or more, about 160 cm or more, about 170 cm or more, about 180 cm or more, about 190 cm or more, or about 200 cm or more and / or about 750 cm or less, about 700 cm or less, about 650 cm or less, about 600 cm or less, about 550 cm or less, about 500 It may be less than cm, less than 450 cm, less than 400 cm, less than 350 cm, less than 300 cm, less than 300 cm, less than 250 cm, less than 200 cm, or less than 150 cm.

[0040] In some embodiments, the length of the tapered band (16) (measured in a direction perpendicular to the width of the intermediate layer shown in FIG. 6) is about 35 cm or more, about 40 cm or more, about 45 cm or more, about 50 cm or more, about 55 cm or more, about 60 cm or more, about 65 cm or more, about 70 cm or more, about 75 cm or more, about 80 cm or more, about 85 cm or more, about 90 cm or more, about 95 cm or more, or about 100 cm or more and / or about 200 cm or less, about 190 cm or less, about 180 cm or less, about 170 cm or less, about 160 cm or less, about 150 cm or less, about 140 cm or less, about 130 cm or less, about 120 cm or less, about 110 cm or less, or about 100 cm or less.

[0041] In some embodiments, where the tapered band (16) does not extend across the entire width of the intermediate layer (10), the distance between the boundaries of the tapered band (16) may be about 5 cm or more, about 10 cm or more, about 15 cm or more, about 20 cm or more, about 25 cm or more, about 30 cm or more, about 35 cm or more, about 40 cm or more, or about 45 cm or more and / or about 200 cm or less, about 175 cm or less, about 175 cm or less, about 150 cm or less, about 100 cm or less, or about 75 cm or less. The width of the tapered band (16) (measured between the thinnest edge (14) and the thickest edge (12) of the tapered band (16) in a direction parallel to the width of the intermediate layer (10) shown in FIG. 6) may be about 60 mm or more, 65 mm or more, about 70 mm or more, about 75 mm or more, about 80 mm or more, about 85 mm or more, about 90 mm or more, about 95 mm or more, or about 100 mm or more and / or about 150 mm or less, about 140 mm or less, about 130 mm or less, about 120 mm or less, about 110 mm or less, about 100 mm or less, about 90 mm or less, about 80 mm or less, or about 70 mm or less. The tapered band (16) (or intermediate layer (10)) has a minimum thickness (T) measured at the thinner end of the tapered band (16) (or intermediate layer (10)). zmin ) and the maximum thickness (T) measured at the thicker end of the tapered band (16) (or intermediate layer (10)) zmax It may include ). In some embodiments, T zminIt may be about 0.25 mm or more, about 0.30 mm or more, about 0.35 mm or more, about 0.38 mm or more, about 0.40 mm or more, about 0.45 mm or more, about 0.50 mm or more, about 0.55 mm or more, about 0.60 mm or more and / or about 2.5 mm or less, about 2.4 mm or less, about 2.3 mm or less, about 2.2 mm or less, about 2.1 mm or less, about 2.0 mm or less, about 1.9 mm or less, about 1.8 mm or less, about 1.7 mm or less, about 1.6 mm or less, about 1.5 mm or less, about 1.4 mm or less, about 1.3 mm or less, about 1.2 mm or less, about 1.1 mm or less, about 1.0 mm or less, about 0.9 mm or less, about 0.85 mm or less, or about 0.80 mm or less.

[0042] T zmax is T zmin It may be at least 0.13 mm, at least about 0.15 mm, at least about 0.20 mm, at least about 0.25 mm, at least about 0.30 mm, at least about 0.35 mm, at least about 0.40 mm, at least about 0.45 mm, at least about 0.50 mm, at least about 0.55 mm, at least about 0.60 mm, at least about 0.65 mm, at least about 0.70 mm, at least about 0.75 mm, at least about 0.80 mm, at least about 0.85 mm, at least about 0.90 mm, at least about 0.95 mm, or at least about 1.0 mm thicker. Alternatively or additionally, T zmax is T zmin It may be thicker than about 2.0 mm or less, about 1.9 mm or less, about 1.8 mm or less, about 1.7 mm or less, about 1.6 mm or less, about 1.5 mm or less, about 1.4 mm or less, about 1.3 mm or less, about 1.2 mm or less, about 1.1 mm or less, or about 1.0 mm or less.

[0043] T zmaxIt may be about 0.35 mm or more, about 0.38 mm or more, about 0.40 mm or more, about 0.45 mm or more, about 0.50 mm or more, about 0.53 mm or more, about 0.55 mm or more, about 0.60 mm or more, about 0.65 mm or more, about 0.70 mm or more, about 0.75 mm or more, or about 0.76 mm or more and / or 2.5 mm or less, about 2.4 mm or less, about 2.3 mm or less, about 2.2 mm or less, about 2.1 mm or less, about 2 mm or less, about 1.9 mm or less, about 1.8 mm or less, about 1.7 mm or less, about 1.6 mm or less, or about 1.5 mm or less.

[0044] When the intermediate layer (10) is a wedge-shaped intermediate layer, the tapered band (16) may include one or more wedge angles (θ), which is defined as an angle formed between a first reference line extending between two points of the intermediate layer where the boundary of the first and second tapered bands intersects the first (upper) surface of the intermediate layer, as generally illustrated in FIG. 1b, and a second reference line extending through two points where the boundary of the first and second tapered bands intersects the second (lower) surface of the intermediate layer. In a specific embodiment, the tapered band (16) may have one or more wedge angles of about 0.05 mrad (milliradian) or more, about 0.10 mrad or more, about 0.13 mrad or more, about 0.15 mrad or more, about 0.20 mrad or more, about 0.25 mrad or more, about 0.30 mrad or more, about 0.35 mrad or more, or about 0.40 mrad or more and / or about 1.0 mrad or less, about 0.90 mrad or less, about 0.85 mrad or less, about 0.80 mrad or less, about 0.75 mrad or less, about 0.70 mrad or less, about 0.65 mrad or less, or about 0.60 mrad or less.

[0045] In some embodiments, the intermediate layer (10) has a total wedge angle of about 0.3 mrad or more, about 0.35 mrad or more, about 0.40 mrad or more, about 0.45 mrad or more, about 0.50 mrad or more, about 0.55 mrad or more, about 0.60 mrad or more, about 0.65 mrad or more, about 0.70 mrad or more, about 0.75 mrad or more and / or about 0.80 mrad or less, about 0.75 mrad or less, about 0.70 mrad or less, about 0.65 mrad or less, about 0.60 mrad or less, about 0.55 mrad or less, about 0.50 mrad or less, about 0.45 mrad or less, about 0.40 mrad or less, about 0.35 mrad or less, or about 0.30 mrad or less.

[0046] In some embodiments, the wedge angle of the intermediate layer (10) may be a constant wedge angle that does not change over the tapered band, and in other embodiments, the tapered band may include two or more constant angle bands having different wedge angles. In this case, the tapered band may have a linear thickness profile. In some embodiments, the wedge angle may vary continuously over all or part of the tapered band, thereby providing a variable angle band having a curved thickness profile. Specific embodiments of the intermediate layer having different tapered band configurations are described in detail in U.S. Patent Application Publication No. 2017 / 0285339, and the entire application is incorporated herein by reference to the extent that it is not inconsistent with the disclosure of the present invention.

[0047] In some embodiments, one or more layers or at least a portion of the intermediate layer (10) may be flattened so that, for example, about 90% or more, about 92% or more, about 95% or more, about 97% or more, about 99% or more, or all of the vertical cross-section of the layer or intermediate layer has a uniform thickness. That is, the intermediate layer (10) may have a cross-sectional geometry that maintains a uniform thickness. One example of a flattened intermediate layer is shown in FIG. 5, and another example is shown in FIG. 12f. An intermediate layer having a flat or uniform thickness profile may have a wedge angle of approximately 0 mrad or less than 0.05 mrad.

[0048] In some embodiments, the intermediate layer (10) may include one or more flat bands (18). As generally illustrated in FIG. 1c, the flat band (18b) of the intermediate layer (10) may be located adjacent to the thickest edge (12) of the tapered band (16) and may have an average thickness of, for example, within about 20%, within about 15%, within about 10%, within about 5%, within about 2%, or within about 1% of the thickness of the thickest edge (12) of the tapered band (16). Additionally or alternatively, the intermediate layer may have a flat band (18a) located adjacent to the thinnest edge (14) of the tapered band (16) and having an average thickness of about 20%, about 15%, about 10%, about 5%, about 2%, or about 1% of the thickness of the thinnest edge (14) of the tapered band (16). In some embodiments, the flat band (or band (18a, 18b)) of the intermediate layer may comprise at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, or at least 40% and / or at least 85%, at least 80%, at least 80%, at least 75%, at least 70%, at least 65%, at least 60%, at least 55%, or at least 50% of the total length (vertical height) of the intermediate layer. Although FIG. 1c is illustrated as comprising both a thin flat band (18a) and a thick flat band (18b), it should be understood that the intermediate layer according to an embodiment of the present invention may comprise one of the thin flat band (18a) and the thick flat band (18b), or the other or both.

[0049] As illustrated in the embodiments of the multilayer intermediate layer shown in FIGS. 1 to 5, the third polymer layer (3) may be located between the first polymer layer (1) and the second polymer layer (2). The third layer may be referred to as a "core" or "inner" layer, and the outer polymer layers (1, 2) may be referred to as a "skin" or "outer" layer. If the intermediate layer comprises more than three layers, the outermost layer, for example, the first and second layers shown in FIG. 2, may be referred to as a skin layer, and the innermost layer, for example, the third layer shown in FIG. 2, may be referred to as a core layer.

[0050] In some embodiments, at least one of the skin layer or the core layer may be wedge-shaped. In some cases, only the outer skin layer may be wedge-shaped, and the inner core layer may be flat or substantially flat. In other cases, one of the skin layers may be wedge-shaped, and the other may be flat. In some cases, both the outermost skin layer and the innermost core layer may be wedge-shaped. In yet another case, the outer layer may be flat, and the inner core layer is wedge-shaped. In other cases, the outer skin layer may be wedge-shaped, and the inner core layer may be wedge-shaped or flat.

[0051] When one or more layers of the intermediate layer (10) are wedge-shaped, the layers may have a wedge angle of about 0.05 mrad or more, about 0.10 mrad or more, about 0.15 mrad or more, about 0.20 mrad or more, about 0.25 mrad or more, about 0.30 mrad or more, or about 0.35 mrad or more and / or about 1 mrad or less, about 0.95 mrad or less, about 0.90 mrad or less, about 0.85 mrad or less, about 0.80 mrad or less, about 0.75 mrad or less, about 0.70 mrad or less, about 0.65 mrad or less, about 0.60 mrad or less, about 0.55 mrad or less. When two or more of the above layers are wedge-shaped, the layers may have substantially similar wedge angles within about 0.001 mrad, about 0.005 mrad, or about 0.01 mrad of each other. In some embodiments, the wedge angles of two of the layers may be within about 15%, within about 10%, within about 5%, within about 3%, within about 2%, or within about 1% of each other.

[0052] Alternatively, one or more wedge-shaped layers may have wedge angles different from one or more other wedge-shaped layers. For example, in some embodiments, where both the inner core layer and one or more outer skin layers are wedge-shaped, the core layer may have a wedge angle greater or smaller than the wedge angle of the core layer(s). In some embodiments, the difference between the wedge angles of two or more wedge-shaped layers may be greater than about 0.05 mrad, greater than about 0.075 mrad, greater than about 0.10 mrad, or greater than about 0.12 mrad. In some embodiments, the wedge angles of two of the layers may be greater than 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, or at least about 40% of each other.

[0053] Overall, each layer of the multilayer intermediate layer (10) may have a thickness of about 0.05 mm or more, about 0.10 mm or more, about 0.15 mm or more, about 0.20 mm or more, about 0.25 mm or more, about 0.30 mm or more, about 0.35 mm or more, or about 0.40 mm or more and / or about 0.60 mm or less, about 0.55 mm or less, about 0.50 mm or less, about 0.45 mm or less, about 0.40 mm or less, about 0.35 mm or less, or less than about 0.30 mm.

[0054] In some embodiments, when the intermediate layer (10) comprises two or more wedge-shaped intermediate layers, these wedge-shaped layers may have a thick end and a thin end opposite the thick end. In some embodiments, one or more thick ends of these wedge-shaped layers are about 5 mil or more, about 6 mil or more, about 7 mil or more, about 8 mil or more, about 9 mil or more, 10 mil or more, about 11 mil or more, about 12 mil or more, about 13 mil or more, about 14 mil or more, about 15 mil or more, about 16 mil or more, about 17 mil or more, about 18 mil or more, about 19 mil or more, about 20 mil or more and / or about 50 mil or less, about 47 mil or less, about 45 mil or less, about 42 mil or less, about 40 mil or less, about 37 mil or less, about 35 mil or less, about 34 mil or less, about 33 mil or less, about 32 mil or less, about 31 mil or less, about 30 mil or less, about 29 mil or less, about It can have a thickness of 28 mil or less, about 27 mil or less, about 26 mil or less, about 25 mil or less, about 24 mil or less, about 23 mil or less, about 22 mil or less, about 21 mil or less, and about 20 mil or less.

[0055] Additionally or alternatively, one or more thin ends of these wedge-shaped layers are about 5 mil or more, about 6 mil or more, about 7 mil or more, about 8 mil or more, about 9 mil or more, about 10 mil or more, about 11 mil or more, about 12 mil or more, about 13 mil or more, about 14 mil or more, about 15 mil or more, about 16 mil or more, about 17 mil or more, about 18 mil or more, about 19 mil or more, about 20 mil or more and / or about 35 mil or less, about 34 mil or less, about 33 mil or less, about 32 mil or less, about 31 mil or less, about 30 mil or less, about 29 mil or less, about 28 mil or less, about 27 mil or less, about 26 mil or less, about 25 mil or less, about 24 mil or less, about 23 mil It can have a thickness of less than, about 22 mil or less, about 21 mil or less, or about 20 mil or less.

[0056] In some embodiments, one or more of the layers may have a thickness different from one or more of the other layers. For example, at least one of the outer skin layers may be thicker than the inner core layer, as illustrated in FIG. 1 through 5. As illustrated in FIG. 2, if a layer exists in addition to the skin layer and the core layer, the additional layer may be thinner than the skin layer and the core layer. In some cases, as illustrated in FIG. 1 through 5, none of the layers may have the same thickness, and in other embodiments, at least two of the layers may have similar thickness. As used herein, "similar thickness" means having a thickness (average or nominal) within 0.02 mm of another layer. As used herein, "different thickness" means having a thickness (average, nominal, or point thickness) that is greater or smaller than another thickness by more than 0.02 mm.

[0057] In some embodiments, the outer skin layers (shown as layers 1 and 2 in FIGS. 1 to 5) may have similar thicknesses such that, for example, the maximum difference between the thicknesses of the two outer layers is about 5% or less, about 3% or less, about 2% or less, about 1% or less, or about 0.5% or less. In some cases, the two outer skin layers may have the same nominal thickness.

[0058] In another embodiment, at least a portion of one outer skin layer (1 or 2) may be thicker than at least a portion of the remaining outer skin layer (2 or 1). For example, in some embodiments, one of the outer skin layers (1 or 2) may be at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, or at least about 50% thicker than the remaining outer skin layer at one or more locations on the intermediate layer. Alternatively or additionally, at least a portion of one outer skin layer (1 or 2) may be thicker than the remaining outer skin layer (2 or 1) at one or more locations along the intermediate layer by 90% or less, about 85% or less, about 80% or less, about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, about 50% or less, or about 45% or less.

[0059] In some embodiments, at one or more locations on the intermediate layer (10), one of the outer skin layers (1 or 2) may have a thickness of less than 0.30 mm, about 0.29 mm or less, about 0.28 mm or less, about 0.27 mm or less, about 0.26 mm or less, about 0.25 mm or less, about 0.24 mm or less, about 0.23 mm or less, about 0.22 mm or less, about 0.21 mm or less, about 0.20 mm or less, about 0.19 mm or less, about 0.18 mm or less, about 0.17 mm or less, or about 0.16 mm or less. Additionally or alternatively, at one or more locations on the intermediate layer, one of the outer skin layers (1 or 2) may have a thickness of about 0.20 mm or more, about 0.22 mm or more, about 0.24 mm or more, about 0.26 mm or more, about 0.28 mm or more, or about 0.29 mm or more. In some cases, at one or more locations on the intermediate layer, at least one of the outer skin layers (1 or 2) may have a thickness in the range of about 0.20 mm to 0.30 mm, at least about 0.22 mm to about 0.30 mm, or about 0.24 mm to about 0.29 mm.

[0060] In some embodiments, if one of the outer skin layers (1 or 2) has a thickness of less than 0.30 mm, the remaining outer skin layer (2 or 1) may have a thickness of more than 0.3 mm, or more than about 0.31 mm, more than about 0.32 mm, more than about 0.33 mm, more than about 0.34 mm, more than about 0.35 mm, or more than about 0.36 mm at one or more locations on the intermediate layer.

[0061] In some embodiments, over about 10%, about 20%, about 40%, about 60%, about 80%, or 100% of the total area of ​​the intermediate layer, one of the outer skin layers (1 or 2) may have a thickness of about 0.30 mm or less, about 0.29 mm or less, about 0.28 mm or less, about 0.27 mm or less, about 0.26 mm or less, or about 0.25 mm, and the remaining outer skin layer (2 or 1) has a thickness of about 0.30 mm or more, about 0.31 mm or more, about 0.32 mm or more, about 0.34 mm or more, or about 0.35 mm or more.

[0062] According to some embodiments, one of the outer skin layers of the intermediate layer (1 or 2) may be at least about 0.01 mm, at least about 0.025 mm, at least about 0.05 mm, at least about 0.075 mm, at least about 0.10 mm, at least about 0.12 mm, at least about 0.15 mm, at least about 0.17 mm, at least about 0.20 mm, at least about 0.22 mm, at least about 0.25 mm, or at least about 0.27 mm thicker than the remaining outer skin layer (2 or 1) (or may be thinner). Additionally or alternatively, one of the outer skin layers (1 or 2) may be thicker (or thinner) than the remaining outer skin layer (2 or 1) by about 0.40 mm or less, about 0.39 mm or less, about 0.38 mm or less, about 0.37 mm or less, about 0.36 mm or less, about 0.35 mm or less, about 0.34 mm or less, about 0.33 mm or less, about 0.32 mm or less, about 0.31 mm or less, about 0.30 mm or less, or about 0.29 mm or less.

[0063] In some embodiments, at one or more locations on the intermediate layer, the ratio of the thickness of one of the outer skin layers (1 or 2) to the thickness of the remaining outer skin layer (2 or 1) may be 2.5 or less:1, about 2.2 or less:1, about 2.0 or less:1, about 1.8 or less:1, about 1.6 or less:1, or about 1.5 or less:1. This thickness difference between the two outer skin layers (1 or 2) may be an average thickness difference across a vertical cross-section of the intermediate layer or a nominal thickness difference of the layers. In other embodiments, particularly when the intermediate layer is a wedge-shaped intermediate layer, the difference may refer to a maximum thickness difference or a thickness difference at a specific distance from one of the edges of the intermediate layer.

[0064] In some embodiments, the total thickness of the two outermost skin layers (1 or 2) may be, on average, about 20 mil or more, about 22 mil or more, about 25 mil or more, about 27 mil or more, about 28 mil or more, about 30 mil or more, about 32 mil or more, about 35 mil or more, about 37 mil or more, about 40 mil or more, about 42 mil or more, or about 45 mil or more and / or about 55 mil or less, about 53 mil or less, about 50 mil or less, about 47 mil or less, about 45 mil or less, about 42 mil or less, about 40 mil or less, about 37 mil or less, about 35 mil or less, about 32 mil or less, or about 30 mil or less.

[0065] If at least one of the skin layers (1 or 2) is a wedge-shaped layer, the total skin thickness at the thinnest edge of the tapered band (16) (or intermediate layer (10)) may be about 20 mil or more, about 22 mil or more, about 25 mil or more, about 27 mil or more, about 28 mil or more and / or about 40 mil or less, about 37 mil or less, about 35 mil or less, about 32 mil or less, or about 30 mil or less. Alternatively or additionally, the total thickness of the two outermost skin layers (1 or 2) at the thickest edge of the tapered band (16) (or intermediate layer (10)) may be about 30 mil or more, about 32 mil or more, about 35 mil or more, about 37 mil or more, about 40 mil or more, about 42 mil or more, about 45 mil or more and / or about 55 mil or less, about 53 mil or less, about 50 mil or less, about 47 mil or less, about 45 mil or less, about 42 mil or less.

[0066] When the intermediate layer (10) has a whole wedge shape, the ratio of the total thickness of the skin layers (1 or 2) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) to the total thickness of the skin layers (1 or 2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) is at least about 1.1:1, at least about 1.2:1, at least about 1.25:1, at least about 1.3:1, at least about 1.3:1, at least 1.35:1, at least about 1.4:1, at least about 1.45:1, at least about 1.5:1 and / or about 1.8:1, about 1.75:1, about 1.7:1, about 1.65:1, about 1.6:1, about 1.55:1, about 1.5 It may be less than:1, approximately 1.45 less than:1, and approximately 1.4 less than:1.

[0067] In some embodiments, the ratio of the thickness of the innermost core layer (3) to the total thickness of the two outermost skin layers (1 or 2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) may be at least about 0.05:1, at least about 0.075:1, at least about 0.10:1, at least about 0.125:1 and / or about 0.25:1, about 0.22:1, about 0.20:1, or about 0.175:1 or less. In some embodiments, the ratio of the thickness of the innermost core layer (3) to the total thickness of the two outer skin layers (1 or 2) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) is at least about 0.05:1, at least about 0.075:1, at least about 0.10:1, at least about 0.125:1, at least about 0.15:1, at least about 0.175:1, at least about 0.20:1, at least about 0.22:1, at least about 0.25:1 and / or about 0.35:1, about 0.32:1, about 0.30:1, about 0.27:1, about 0.25:1, about 0.22:1, about 0.20:1, about 0.175:1, about 0.15:1, about 0.125 or less:1, approximately 0.10 or less:1 may be possible.

[0068] In some embodiments, the core layer (3) may be thinner than one or both of the outer skin layers (1, 2). For example, the core layer (3) may be thinner than at least one (or both) of the outer skin layers (1, 2) over about 25%, about 50%, about 75%, about 95%, or 100% of the total area of ​​the intermediate layer (10). For example, in some embodiments, one of the outer skin layers (1 or 2) may be thinner than the remaining outer skin layer (2 or 1) over about 25%, about 50%, about 75%, about 95%, or 100% of the total area of ​​the intermediate layer (10), and may be, for example, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, or at least about 60% thicker (or thinner) than the remaining outer skin layer (2 or 1).

[0069] In some embodiments, over about 25%, about 50%, about 75%, about 95%, or 100% of the total area of ​​the intermediate layer (10), one of the outer skin layers (1 or 2) may be at least about 0.01 mm, at least about 0.025 mm, at least about 0.05 mm, at least about 0.075 mm, at least about 0.1 mm, or at least about 0.15 mm thinner than the remaining outer skin layers (2 or 1). Additionally or alternatively, one of the skin layers (1 or 2) may be thinner than the remaining outer skin layer (2 or 1) by about 0.5 mm or less, about 0.45 mm or less, about 0.40 mm or less, about 0.35 mm or less, about 0.30 mm or less, about 0.25 mm or less, about 0.25 mm or less, 0.20 mm or less, or about 0.15 mm or less. This difference in thickness may be a difference in average thickness or nominal thickness, or in the case of a wedge-shaped intermediate layer (10), this difference may be a difference in maximum thickness or a difference in thickness at a specified location.

[0070] Now, referring to FIGS. 12a through 12e, several additional wedge-shaped intermediate layers (10) configured according to embodiments of the present invention are shown. In particular, as shown in FIGS. 12a through 12e, the thickness of one of the outer polymer layers (shown as the first polymer layer "1" in FIGS. 12a through 12e) may be greater at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) than at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)). In other words, the thick end of the wedge-shaped first layer (1) may be located at the thinnest edge (14) of the tapered band (16), and the thin end of the first layer (1) may be located at the thickest edge (12) of the tapered band (16).

[0071] This configuration is referred to herein as a "reverse wedge" profile. Although described herein in relation to the first polymer layer, it should be understood that the dimensions and configuration of the embodiments of the invention are similarly applied to the second layer (2) according to the configuration of the intermediate layer.

[0072] Further embodiments of the intermediate layer (10) illustrated in FIG. 12f and 12g illustrate other embodiments according to the present invention, wherein the entire intermediate layer is not wedge-shaped (Fig. 12f), or where all three layers are wedge-shaped, the thinner end of the core layer (3) is located at the tapered band (16) or the thickest edge (14) of the intermediate layer (10) (Fig. 12g).

[0073] In one or more embodiments, the thickness of the first polymer layer (1) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) is at least 0.05 mm, at least about 0.10 mm, at least about 0.15 mm, or at least about 0.20 mm and / or about 0.3 mm or less, about 0.25 mm or less, about 0.20 mm or less, or about 0.15 mm or less than the thickness of the first polymer layer (1) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)). Consequently, the first polymer layer (1) of the intermediate layer (10) illustrated in FIG. 12a through 12e generally has an "inverted" wedge-shaped profile.

[0074] In some embodiments, examples are illustrated in FIGS. 12a to 12c, and the remaining outer layer (illustrated as the second polymer layer "2" in FIGS. 12a to 12c) may also have a wedge shape and may have a thickness at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) less than the thickness at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)). In one or more embodiments, the thickness of the second polymer layer (2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) may be thinner than the thickness of the second polymer layer (2) at the thickest edge (14) of the tapered band (16) (or intermediate layer (10)) by at least 0.05 mm, at least about 0.10 mm, at least about 0.15 mm, or at least about 0.20 mm and / or about 0.3 mm or less, about 0.25 mm or less, about 0.20 mm or less, or about 0.15 mm or less. Consequently, the second polymer layer (2) may have a wedge-shaped profile similar to the wedge-shaped profile of the tapered band (16) or the entire intermediate layer (10). As shown in FIGS. 12d and 12f, for example, the second polymer layer (2) may be a flat layer having a substantially uniform (non-tapered) profile and a substantially constant thickness.

[0075] In one or more embodiments, one of the outer polymer layers (1 or 2) may be thinner overall than the remaining outer polymer layers (2 or 1). For example, one polymer layer (1 or 2) may have an average thickness of about 0.05 mm or more, about 0.075 mm or more, about 0.10 mm or more, about 0.15 mm or more, or about 0.2 mm or more and / or about 0.25 mm or less, about 0.20 mm or less, about 0.15 mm or less, about 0.10 mm or less, about 0.075 mm or less, or about 0.05 mm or less than the average thickness of the remaining polymer layers (2 or 1). As used herein, the term “average thickness” refers to the thickness of a layer or intermediate layer measured at 10 uniformly spaced positions over the entire vertical height of the intermediate layer and then averaged (i.e., divided by 10).

[0076] In one or more embodiments, the ratio of the mass of the first polymer layer (1) to the combined total mass of the first and second polymer layers (1 or 2) may be at least about 0.10:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, at least about 0.40:1, at least about 0.45:1, at least about 0.50:1 and / or about 0.95:1 or less, about 0.90:1, at least about 0.85:1, at least about 0.80:1, at least about 0.75:1, at least about 0.70:1, at least about 0.65:1, at least about 0.60:1, at least about 0.55:1, at least about 0.50:1, or at least about 0.45:1.

[0077] In one or more embodiments, the thickness of the first polymer layer (1) may be greater than the thickness of the second polymer layer (2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)). For example, the thickness of the first polymer layer (1) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) is at least about 0.005 mm, at least about 0.01 mm, at least about 0.025 mm, at least about 0.05 mm, at least 0.075 mm and / or about 0.15 mm or less, about 0.125 mm or less, about 0.15 mm or less, about 0.15 mm or less, or about 0.075 mm or less than the thickness of the second polymer layer (2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)).

[0078] In one or more embodiments, the ratio of the thickness of the first polymer layer (1) to the thickness of the second polymer layer (2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) may be at least about 1.05:1, at least about 1.1:1, at least about 1.2:1, at least about 1.25:1, at least about 1.3:1, at least about 1.35:1, at least about 1.4:1, at least about 1.45:1, or at least about 1.5:1 and / or about 5:1, about 4.5:1, about 4:1, about 3.5:1, about 3:1, about 2.5:1, or about 2:1.

[0079] In some embodiments, the ratio of the thickness of the first polymer layer (1) to the thickness of the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) is at least 0.20:1, at least about 0.25:1, about 0.30:1, at least about 0.35:1, at least about 0.40:1, at least about 0.45:1, or at least about 0.50:1 and / or 0.85:1, about 0.80:1, about 0.75:1, about 0.70:1, about 0.65:1, about 0.60:1, about 0.55:1, about 0.50:1, about 0.45:1 or about 0.40:1.

[0080] In some embodiments, the ratio of the thickness of the second polymer layer (2) of the tapered band (16) (or intermediate layer (10)) to the thickness of the thinnest edge (14) is at least about 0.1:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, or at least about 0.40:1 and / or 0.45:1, about 0.40:1, about 0.35:1, about 0.30:1, or about 0.25:1.

[0081] In some embodiments, the ratio of the thickness of the first polymer layer (1) to the thickness of the second polymer layer (2) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) may be at least about 0.10:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1 and / or about 0.75:1, about 0.70:1, about 0.65:1, about 0.60:1, about 0.55:1, about 0.50:1, about 0.45:1, about 0.40:1, or about 0.35:1. The ratio of the thickness of the first polymer layer (1) to the thickness of the second polymer layer (2) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) may be at least about 0.10:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1 and / or about 0.75:1, about 0.70:1, about 0.65:1, about 0.60:1, about 0.55:1, about 0.50:1, about 0.45:1, about 0.40:1, or about 0.35:1.

[0082] Additionally or alternatively, the thickness of the first polymer layer (1) may be thinner than the thickness of the second polymer layer (2) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)), as generally illustrated in FIG. 12a to 12e. For example, the thickness of the first polymer layer (1) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) may be thinner than the thickness of the second polymer layer (2) at the thickest part of the tapered band (16) (or intermediate layer (10)) to at least about 0.05 mm, at least about 0.10 mm, at least about 0.15 mm, at least about 0.20 mm, or at least about 0.25 mm and / or about 0.35 mm or less, about 0.30 mm or less, about 0.25 mm or less, about 0.20 mm or less, about 0.15 mm or less, or about 0.10 mm or less.

[0083] In one or more embodiments, the ratio of the thickness of the first polymer layer (1) to the thickness of the second polymer layer (2) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) is at least about 0.10:1, at least about 0.15:1, at least about 0.2:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, at least about 0.4:1, at least about 0.5:1, at least about 0.6:1, or at least about 0.75:1 and / or about 0.99:1, about 0.95:1, about 0.90:1, about 0.85:1, about 0.80:1, about 0.75:1, 0.70:1, 0.65:1, 0.55:1, 0.50 Less than:1, Less than 0.45:1, Less than 0.40:1, Less than 0.35:1. In one or more embodiments, the ratio of the thickness of the second polymer layer (2) to the thickness of the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) is at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, at least about 0.40:1, at least about 0.45:1 or more, or at least about 0.50:1 and / or about 0.85:1, about 0.85:1, 0.80:1, about 0.75:1, about 0.70:1, about 0.65:1, about 0.60:1, about 0.55:1, about 0.50:1, about 0.45:1 or about 0.40:1. In one or more embodiments, the ratio of the thickness of the first polymer layer (1) of the tapered band (16) (or intermediate layer (10)) to the thickness of the thickest edge (12) is at least about 0.1:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, or at least about 0.40:1 and / or 0.45:1, about 0.40:1, about 0.35:1, about 0.30:1, or about 0.25:1.

[0084] Additionally, in one or more embodiments, the third polymer layer (illustrated as the innermost layer or core layer “3”) in FIG. 12a through 12d may be a wedge-shaped layer. In one or more embodiments, the thickness of the third polymer layer (3) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) may be less than the thickness of the third polymer layer (3) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)). Thus, the third polymer layer (3) may also have a wedge-shaped profile similar to the overall profile of the intermediate layer (10). In some embodiments, as illustrated in FIG. 12a, for example, the third polymer layer (3) may be a flat layer having a substantially uniform (non-tapered) profile.

[0085] In one or more embodiments, the ratio of the thickness of the third layer (3) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) to the thickness of the third layer (3) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) is at least about 1:1, at least about 1.05:1, at least about 1.1:1, at least about 1.15:1, at least about 1.2:1, at least about 1.25:1, at least about 1.5:1, at least about 2:1, at least about 2.5:1, at least about 3:1, or at least about 3.5:1 and / or about 5:1, about 4.5:1, about 4:1, about 3.5:1, about 3:1, about 2.5:1, about 2:1, about 1.5:1, about It may be 1.25 or less:1, about 1.15 or less:1, or about 1 or less:1, or 1:1.

[0086] In one or more embodiments, the ratio of the thickness of the third polymer layer (3) of the tapered band (16) (or intermediate layer (10)) to the total thickness of the thickest edge (12) is at least about 0.05:1, at least about 0.10:1, at least about 0.15:1 or more, or at least about 0.20:1 and / or about 0.40:1, about 0.35:1, about 0.30:1, about 0.25:1, about 0.20:1, about 0.15:1, or about 0.10:1. The ratio of the thickness of the third polymer layer (3) of the tapered band (16) (or intermediate layer (10)) to the total thickness of the thinnest edge (14) is at least about 0.05:1, at least about 0.10:1, at least about 0.15:1, at least about 0.20:1, at least about 0.25:1, at least about 0.30:1, at least about 0.35:1, at least about 0.40:1, at least about 0.45:1, at least about 0.50:1 and / or about 0.80 or less:1, about 0.75 or less:1, about 0.70 or less:1, about 0.65 or less:1, about 0.60 or less:1, about 0.55 or less:1, about 0.50 or less:1, about 0.45 or less:1, about 0.35 or less:1, about 0.30 or less:1, about It may be 0.25 or less:1, about 0.20 or less:1, about 0.15 or less:1, or about 0.10 or less:1.

[0087] In one or more embodiments, the ratio of the thickness of the third polymer layer (3) to the thickness of the first polymer layer (1) at the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)) may be at least about 0.05:1, at least about 0.10:1, at least about 0.15:1, at least about 0.20:1 and / or about 0.50:1, about 0.45:1, about 0.40:1, about 0.35:1, about 0.30:1, about 0.25:1, or about 0.20:1. Additionally or alternatively, the ratio of the thickness of the third polymer layer (3) to the thickness of the first polymer layer (1) at the thickest edge (12) of the tapered band (16) (or intermediate layer (10)) may be at least about 0.40:1, at least about 0.50:1, at least about 0.60:1, at least about 0.70:1, at least about 0.80:1, or at least about 0.90:1 and / or about 5:1, about 4.5:1, about 4:1, about 3.5:1, about 3:1, about 2.5:1, about 2:1, about 1.5:1, about 1.1:1, about 0.90:1, about 0.80:1, about 0.75:1, or about 0.50:1.

[0088] In some embodiments, the third layer (3) may have a thickness of about 3.5 mil or more, about 4 mil or more, about 4.5 mil or more, about 5 mil or more and / or about 10 mil or less, about 9 mil or less, about 8 mil or less, about 7 mil or less, about 6 mil or less, about 5 mil or less. In some embodiments, the thick end of the third layer (3) may have a thickness of about 3.5 mil or more, about 4 mil or more, about 4.5 mil or more, about 5 mil or more, about 5.5 mil or more, about 6 mil or more, about 6.5 mil or more, about 7 mil or more, about 7.5 mil or more, about 8 mil or more, or about 8.5 mil or more and / or about 22.5 mil or less, about 20 mil or less, about 17 mil or less, about 15 mil or less, about 14 mil or less, about 13 mil or less, about 12 mil or less, about 11 mil or less, about 10 mil or less, about 9.5 mil or less. If the third layer (3) is flat, it may have an average thickness of about 3.5 mil or more, about 4 mil or more, about 4.5 mil or more, about 5 mil or more, about 5.5 mil or more, about 6 mil or more, about 6.5 mil or more, about 7 mil or more, about 7.5 mil or more, about 8 mil or more, or about 8.5 mil or more and / or about 22.5 mil or less, about 20 mil or less, about 17 mil or less, about 15 mil or less, about 14 mil or less, about 13 mil or less, about 12 mil or less, about 11 mil or less, about 10 mil or less, about 9.5 mil or less, about 9 mil or less, about 8 mil or less, about 7 mil or less, about 6 mil or less, or about 5 mil or less.

[0089] Now, referring to FIG. 8, a thickness profile of an intermediate layer (10) according to various embodiments of the present invention is illustrated. In some embodiments, examples are illustrated in FIG. 8, and at least one (or both) of the outer layers (1, 2) of the intermediate layer may have a thickness that does not exceed a certain maximum thickness within a set distance from one of the edges of the intermediate layer. For example, in some embodiments, the thickness of at least one of the outer layers (1, 2) may not exceed 0.3 mm within about 40 cm of the thinnest edge (14) of the intermediate layer, as illustrated in FIG. 8 and schematically illustrated in FIG. 6 (as an intermediate layer) and FIG. 7 (laminated glass or windshield).

[0090] In some cases, the maximum thickness of at least one of the outer layers (1, 2) may not exceed 0.30 mm, 0.29 mm, 0.28 mm, 0.27 mm, 0.26 mm, or 0.25 mm within about 10 cm, about 20 cm, about 30 cm, or about 40 cm of the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)). In some cases, the maximum thickness of at least one of the outer layers (1, 2) may not exceed 0.30 mm within about 45 cm, about 50 cm, about 55 cm, about 60 cm, about 65 cm, about 70 cm, or about 75 cm, or about 80 cm of the thinnest edge (14) of the tapered band (16) (or intermediate layer (10)). These ranges may also be applied when the intermediate layer (10) is used to form the windshield (20), in which case the thinnest edge (14) is located at the lower edge (in a vertically installed state), as generally illustrated in FIG. 7.

[0091] Now, referring to FIG. 9, the thickness profile of at least one (or both) of the outer skin layers is illustrated, wherein the minimum and maximum thicknesses are illustrated as a function of position. More specifically, FIG. 9 shows the maximum thickness (T) applicable to at least one of the outer skin layers. max ) and minimum thickness of the same outer layer (T min It provides a pictorial example of ). Accordingly, the shaded area between the curves shown in FIG. 9 represents the possible thickness range for the outer layer as a function of the position for the first 100 cm of the intermediate layer, measured from its thinnest edge.

[0092] As shown in FIG. 9, the maximum thickness (T) of the outer skin layer as a function of the distance from the thinnest edge. max ) can be expressed by the following Equation I:

[0093] [Food I]

[0094] T max = 1.975141 - (1.6936517) / (1+( D e / 155.2664)^3.324064)

[0095] In the above formula, D e is the distance (cm) from the thinnest edge of the middle layer.

[0096] The minimum thickness of the outer skin layer, which is also expressed as a function of the distance from the thinnest edge, can be expressed by the following Equation II:

[0097] [Equation II]

[0098] T min = 0.0014 D e + 0.06

[0099] In the above formula, D e is the distance (cm) from the thinnest edge of the middle layer.

[0100] Alternatively or additionally, the minimum thickness of the outer skin layer may also be represented by one of the following other formulas III and IV:

[0101] [Equation III]

[0102] T min = 0.0024 D e + 0.06

[0103] [Essence IV]

[0104] T min = 0.002 D e + 0.10

[0105] In the above formula, D e is the distance (cm) from the thinnest edge of the middle layer.

[0106] Each of Equations II to IV is T in the thickness profile shown in FIG. 9. min It is an equation possible to represent the lower line illustrating, and Equation I is T as a function of position max It represents the upper line of.

[0107] In some embodiments, at least one (or both) of the outer skin layers may have a thickness profile defined by the following formula V:

[0108] [Essence V]

[0109] [0.0024( D e ) + 0.06] < T 1 < [1.975141 - (1.6936517) / (1 + ( D e / 155.2664)^3.324064)]

[0110] In the above formula,

[0111] D e is the distance (cm) from the thinnest edge of the intermediate layer, and

[0112] T 1silver D e The thickness of the first layer (mm) in the figure corresponds to the shaded area of ​​Figure 9.

[0113] Now, referring to FIG. 13, another embodiment of a wedge-shaped intermediate layer (10) according to an embodiment of the present invention is provided. The wedge-shaped intermediate layer (10) illustrated in FIG. 13 comprises a pair of skin layers (first and second layers (1 or 2)) and a core layer (third layer (3)). As previously stated, the use of “first,” “second,” “third,” etc. is used solely for the purpose of facilitating discussion herein and is not intended to be limiting unless otherwise noted.

[0114] As illustrated in FIG. 13, the wedge-shaped intermediate layer (10) can be configured such that the following relationship is satisfied at all points along the vertical centerline (illustrated as the dashed line Z-Z' in FIG. 13) extending between the thinnest edge (14) and the thickest edge (12):

[0115] 1.25Tca > TcL > 0.75Tca

[0116] In the above formula,

[0117] TcL is the local total thickness of the first and second layers, and

[0118] Tca is the average total thickness of the first and second layers calculated as follows:

[0119] Tca = (Tc1 + Tc2) / 2,

[0120] At this time, Tc1 is the total thickness of the first and second layers (1 or 2) at the thinnest edge (14), and Tc2 is the total thickness of the first and second layers (1 or 2) at the thickest edge (12).

[0121] As illustrated in FIG. 13, Tc1 is calculated by adding the thickness of the first layer (1) at the thinnest edge (14) (indicated as T1s1) and the thickness of the second layer (2) at the thinnest edge (14) (indicated as T2s1), and Tc2 is calculated by adding the thickness of the first layer (1) at the thickest edge (12) (indicated as T1s2) and the thickness of the second layer (2) at the thickest edge (12) (indicated as T2s2). The formulas for Tc1 and Tc2 are as follows:

[0122] Tc1 = T1s1 + T2s1 (thinnest edge),

[0123] Tc2 = T1s2 + T2s2 (thickest edge).

[0124] For example, the local total thickness of the first and second layers (1 or 2) at each of arbitrarily selected points X, Y, and Z (indicated as TcLX, TcLY, and TcLZ in FIG. 13) falls within the ranges of 1.25 Tca and 0.75 Tca, respectively, where Tca is defined as above. Thus, in some embodiments, despite variations in the thickness of individual skin layers at various locations along the vertical centerline of the intermediate layer, the total thickness is substantially constant and substantially similar to the average of the total thickness at any one end of the tapered band (16) (or intermediate layer (10)).

[0125] In some embodiments, Tca may be about 25 mil or more, about 27 mil or more, about 30 mil or more, about 32 mil or more, about 34 mil or more, about 35 mil or more, about 36 mil or more and / or about 45 mil or less, about 42 mil or less, about 40 mil or less, about 38 mil or less, about 37 mil or less, or about 35 mil or less. In addition to the values ​​for Tc1 and Tc2, the total thickness of the skin layers (1 or 2) along the vertical centerline as shown in FIG. 13 may also fall within one or more of the ranges provided herein.

[0126] In some embodiments, the average local total thickness (Tcavg) of the first and second layers (1 or 2) taken at a point 10 (20, 30, 40, 50, or 60) equally spaced between the thinnest edge (14) and the thickest edge (12) of the tapered band (16) may satisfy the following equation:

[0127] 1.25Tcavg > TcL > 0.75 Tcavg

[0128] In the above formula, TcL is the local total thickness of the first and second layers (1 or 2).

[0129] In some embodiments, the upper limit of the range may be 1.2 Tcavg, 1.15 Tcavg, 1.1 Tcavg, or 1.05 Tcavg or less. In some embodiments, the lower limit of the range may be at least 0.80 Tcavg, 0.85 Tcavg, 0.90 Tcavg, or 0.95 Tcavg. In some embodiments, the formula may be satisfied at all points between the thinnest edge (14) and the thickest edge (12) of the tapered band (16).

[0130] Each layer of the multilayer intermediate layer may be formed from one or more thermoplastic polymers. Examples of suitable thermoplastic polymers include, but are not limited to, poly(vinyl acetal) resin, polyurethane (PU), poly(ethylene-co-vinyl acetate) (EVA), polyvinyl chloride (PVC), poly(vinyl chloride-co-methacrylate), polyethylene, polyolefin, ethylene acrylate ester copolymer, poly(ethylene-co-butyl acrylate), silicone elastomer, epoxy resin, and acid copolymers, e.g., ethylene / carboxylic acid copolymer and its ionomer, derived from any polymer previously listed, and combinations thereof. In some embodiments, the thermoplastic polymer may be selected from the group consisting of poly(vinyl acetal) resin, polyvinyl chloride, and polyurethane, or the resin may comprise one or more poly(vinyl acetal) resins. Although described herein in relation to poly(vinyl acetal) resin and particularly poly(vinyl butyral) resin, it should be understood that one or more of the said polymer resins may be included together with or instead of the poly(vinyl acetal) resin according to various embodiments of the present invention.

[0131] Where the resin composition, layer, and intermediate layer described herein comprise a poly(vinyl acetal) resin, said poly(vinyl acetal) resin may be formed according to any suitable method. The poly(vinyl acetal) resin may be formed by the acetalization of a polyvinyl alcohol using one or more aldehydes in the presence of an acid catalyst. Subsequently, the resulting resin is separated, stabilized, and dried according to known methods, for example, U.S. Patents No. 2,282,057 and No. 2,282,026, as well as methods described in the literature [Wade, B. 2016, Vinyl Acetal Polymers, Encyclopedia of Polymer Science and Technology. 1-22 (online, copyright 2016 John Wiley & Sons, Inc.)]. The resulting poly(vinyl acetal) resin may have a total acetalization percentage of about 50 wt% or more, about 60 wt% or more, about 70 wt% or more, about 75 wt% or more, about 80 wt% or more, or about 85 wt%, when measured according to ASTM D-1396, unless otherwise noted. The total amount of aldehyde residues in the poly(vinyl acetal) resin may be collectively referred to as the acetal component, and the remainder of the poly(vinyl acetal) resin is residual vinyl alcohol (hydroxyl) and residual acetate groups, which will be discussed in more detail below.

[0132] In some embodiments, at least one or all of the layers of the multilayer intermediate layer may comprise one or more poly(vinyl acetal) resins in an amount of about 0.5 wt% or more, about 1 wt% or more, about 2 wt% or more, about 3 wt% or more, about 5 wt% or more, about 10 wt% or more, about 15 wt% or more, about 20 wt% or more, about 30 wt% or more, about 40 wt% or more, about 45 wt% or more, or about 50 wt% or more, based on the total weight of all resins in the layer. The one or more poly(vinyl acetal) resins may constitute about 10 wt% or more, about 20 wt% or more, about 30 wt% or more, about 40 wt% or more, about 50 wt% or more, about 60 wt% or more, about 70 wt% or more, or about 80 wt% or more, based on the total weight of all resins. In some embodiments, the amount of resin other than the one or more poly(vinyl acetal) resins may be about 20 weight percent or less, about 15 weight percent or less, about 10 weight percent or less, about 5 weight percent or less, about 2 weight percent or less, or about 1 weight percent or less, based on the total weight of all resins. In some cases, the layer may comprise only a single poly(vinyl acetal) resin, and in other cases, may comprise two or more blends. The composition of each layer of the multilayer intermediate layer may be the same, or one or more layers may differ from one or more other layers within the intermediate layer.

[0133] The poly(vinyl acetal) resin(s) used in the layers of the above multilayer intermediate layer may include any suitable aldehyde residue, and in some embodiments, one or more C1 to C 10It may include an aldehyde residue, or one or more C4 to C8 aldehyde residues. Suitable examples of C4 to C8 aldehydes may include, butyrrhaldehyde, iso-butyraldehyde, 2-methylvaleraldehyde, n-hexylaldehyde, 2-ethylhexylaldehyde, n-octylaldehyde, and combinations thereof. In some embodiments, the poly(vinyl acetal) resin(s) used in the layer(s) may comprise at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 60 wt%, or at least 70 wt% of one or more C4 to C8 aldehyde residues based on the total weight of the aldehyde residues in the resin, and / or may comprise at least 90 wt%, at least 85 wt%, at least 80 wt%, at least 75 wt%, at least 70 wt%, or at least 65 wt% of one or more C4 to C8 aldehydes, or at least 20 wt% to at least 90 wt%, at least 30 wt% to at least 80 wt%, or at least 40 wt% to at least 70 wt% of one or more C4 to C8 aldehydes. The above C4 to C8 aldehydes may be selected from the group listed above, or may be selected from the group consisting of n-butyraldehyde, iso-butyraldehyde, 2-ethylhexylaldehyde, and combinations thereof.

[0134] In some embodiments, the poly(vinyl acetal) resin may be a polyvinyl butyral (PVB) resin. In other embodiments, the poly(vinyl acetal) resin may be a poly(vinyl n-butyral) resin containing mainly n-butyraldehyde residues, and may contain aldehyde residues other than n-butyraldehyde, for example, about 50 weight% or less, about 40 weight% or less, about 30 weight% or less, about 20 weight% or less, about 10 weight% or less, about 5 weight% or less, or about 2 weight% or less, based on the total weight of all aldehyde residues of the resin.

[0135] Where the above poly(vinyl acetal) resin includes PVB resin, the molecular weight of the resin may be about 50,000 Da (dalton) or more, about 70,000 Da or more, about 100,000 Da or more and / or about 600,000 Da or less, about 550,000 Da or less, about 500,000 Da or less, about 450,000 Da or less, or 425,000 Da or less, when measured by size exclusion chromatography using the Cotts and Ouano low-angle laser light scattering (SEC / LALLS) method. In this document, the term "molecular weight" refers to the weight-average molecular weight (M w It refers to ). The molecular weight of the poly(vinyl acetal) resin may be in the range of about 50,000 Da to about 600,000 Da, about 70,000 Da to about 450,000 Da, or about 100,000 Da to about 425,000 Da.

[0136] According to some embodiments, two or more layers of the multilayer intermediate layer may have different compositions. For example, in some embodiments, one or both of the outer skin layers may be formed from a first poly(vinyl acetal) resin, and the core layer or inner layer may be formed from a second poly(vinyl acetal) resin. In some embodiments, the poly(vinyl acetal) resin used to form the first layer may have a residual hydroxyl content and / or residual acetate content that is at least about 2 wt%, at least about 3 wt%, at least about 4 wt%, at least about 5 wt%, at least about 6 wt%, or at least about 8 wt% higher or lower than the residual hydroxyl content and / or residual acetate content of the second poly(vinyl acetal) resin used to form the second layer.

[0137] In this document, the terms "residual hydroxyl content" and "residual acetate content" refer, respectively, to the amounts of hydroxyl groups and acetate groups remaining on the resin after the treatment is completed. For example, polyvinyl n-butyral can be prepared by hydrolyzing polyvinyl acetate into polyvinyl alcohol and then acetalizing the polyvinyl alcohol with n-butyraldehyde to form polyvinyl n-butyral. During the hydrolysis of polyvinyl acetate, not all acetate groups are converted into hydroxyl groups, and residual acetate groups remain on the resin. Similarly, during the acetalization of polyvinyl alcohol, not all hydroxyl groups are converted into acetal groups, and residual hydroxyl groups remain on the resin. Consequently, most poly(vinyl acetal) resins contain both residual hydroxyl groups (as vinyl hydroxyl groups) and residual acetate groups (as vinyl acetate groups) as part of the polymer chain. The residual hydroxyl content and residual acetate content are expressed in weight percent based on the weight of the polymer resin and, unless otherwise specified, are measured according to ASTM D-1396.

[0138] In some cases, the difference between the residual hydroxyl contents of the poly(vinyl acetal) resin in two or more layers (e.g., first and third layers and / or second and third layers) may also be about 2 wt% or more, about 5 wt% or more, about 10 wt% or more, about 12 wt% or more, about 15 wt% or more, about 20 wt% or more, or about 30 wt% or more. As used herein, the terms “~wt% different” or “the difference is ~wt% or more” refer to the difference between two presented wt%s calculated by subtracting the remaining wt% from one presented wt%. For example, a poly(vinyl acetal) resin having a residual hydroxyl content of 12 wt% has a residual hydroxyl content 2 wt% lower than a poly(vinyl acetal) resin having a residual hydroxyl content of 14 wt% (14 wt% - 12 wt% = 2 wt%). In this document, the term "different" may refer to a value that is higher or lower than another value.

[0139] At least one of the poly(vinyl acetal) resins used in one or more polymer layers is in an amount of about 14 wt% or more, about 14.5 wt% or more, about 15 wt% or more, about 15.5 wt% or more, about 16 wt% or more, about 16.5 wt% or more, about 17 wt% or more, about 17.5 wt% or more, about 18 wt% or more, about 18.5 wt% or more, about 19 wt% or more, about 19.5 wt% or more and / or about 45 wt% or less, about 40 wt% or less, about 35 wt% or less, about 33 wt% or less, about 30 wt% or less, about 27 wt% or less, about 25 wt% or less, about 24 wt% or less, about 23.5 wt% or less, about 23 wt% or less, about 22.5 wt% or less, about 22 wt% or less, about 21.5 wt% or less, about 21 wt% or less, It may have a residual hydroxyl content in the range of about 20.5 wt% or less, or about 20 wt% or less, or about 14 wt% to about 45 wt%, about 16 wt% to about 30 wt%, about 18 wt% to about 25 wt%, about 18.5 wt% to about 20 wt%, or about 19.5 wt% to about 21 wt%.

[0140] Another poly(vinyl acetal) resin used in one or more layers of the above intermediate layer is at least about 8 wt%, about 9 wt%, about 10 wt%, about 11 wt% and / or about 30 wt% or less, about 29 wt% or less, about 28 wt% or less, about 27 wt% or less, about 26 wt% or less, about 25 wt% or less, about 24 wt% or less, about 23 wt% or less, about 22 wt% or less, about 21 wt% or less, about 20 wt% or less, about 19 wt% or less, about 19.5 wt% or less, about 18 wt% or less, about 17.5 wt% or less, about 17 wt% or less, about 16.5 wt% or less, about 16 wt% or less, about 15 wt% or less, about 14.5 wt% or less, about 13 wt% or less, about 11.5 wt% or less, about 11 wt% or less, It may have a residual hydroxyl content in the range of about 10.5 wt% or less, about 10 wt% or less, about 9.5 wt% or less, or about 9 wt% or less, or about 8 wt% to about 16 wt%, about 9 wt% to about 15 wt%, or about 9.5 wt% to about 14.5 wt%, and may be selected such that the difference between the residual hydroxyl contents of the poly(vinyl acetal) resins used to form two or more polymer layers is about 2 wt% or more, or within one or more of the previously mentioned ranges.

[0141] In some embodiments, for example, at least one of the poly(vinyl acetal) resins used to form two different layers within the intermediate layer may have a residual acetate content different from the remaining resin. For example, in some embodiments, the difference (or maximum difference) between the residual acetate contents of the two poly(vinyl acetal) resins (or any layers of the intermediate layer) may be about 2 wt% or more, about 3 wt% or more, about 4 wt% or more, about 5 wt% or more, about 8 wt% or more, about 10 wt% or more and / or about 15 wt% or less, about 13 wt% or less, about 10 wt% or less, about 8 wt% or less, about 6 wt% or less, about 4 wt% or less, about 1 wt% or less, or about 0.5 wt% or less. One of the above poly(vinyl acetal) resins may have a residual acetate content of less than 15 wt%, about 13 wt% or less, about 12 wt% or less, about 10 wt% or less, about 8 wt% or less, about 6 wt% or less, about 5 wt% or less, about 4 wt% or less, about 3 wt% or less, about 2 wt% or less, about 1 wt% or less, or about 0.5 wt% or less when measured as described above.

[0142] In some embodiments, at least one of the poly(vinyl acetal) resins used to form the layer of the intermediate layer may have a residual acetate content of about 5 wt% or more, about 8 wt% or more, about 10 wt% or more, 12 wt% or more, about 14 wt% or more, about 16 wt% or more, about 18 wt% or more, about 20 wt% or more, or about 30 wt% or more. The difference in residual acetate content between the poly(vinyl acetal) resins used in two or more polymer layers may be within the range provided above, or the difference may be less than about 3 wt%, about 2 wt% or less, about 1 wt% or less, or about 0.5 wt% or less.

[0143] In some embodiments, the difference in residual hydroxyl content between the poly(vinyl acetal) resins used in two or more layers may be less than about 2 wt%, about 1 wt% or less, or about 0.5 wt% or less, and the difference in residual acetate content between the poly(vinyl acetal) resins used in two or more layers may be about 3 wt% or more, about 5 wt% or more, about 8 wt% or more, about 15 wt% or more, about 20 wt% or more, or about 30 wt% or more. In another embodiment, the difference in residual acetate content of poly(vinyl acetal) resins in two or more layers may be less than about 3 wt%, about 2 wt% or less, about 1 wt% or less, or about 0.5 wt% or less, and the difference in residual hydroxyl content of the same poly(vinyl acetal) resins may be about 2 wt% or more, about 5 wt% or more, about 10 wt% or more, about 12 wt% or more, about 15 wt% or more, about 20 wt% or more, or about 30 wt% or more.

[0144] In various embodiments, differences in the residual hydroxyl and / or residual acetate content of the poly(vinyl acetal) resin in two or more of the polymer layers, for example, including a skin layer and a core layer, may be selected to control specific performance characteristics (e.g., strength, impact resistance, penetration resistance, processability, or acoustic performance for the final composition, layer, or intermediate layer). For example, a poly(vinyl acetal) resin having a higher residual hydroxyl content (generally, more than about 16 weight%) may promote high impact resistance, penetration resistance, and strength for the resin composition or layer, and a poly(vinyl acetal) resin having a lower residual hydroxyl content (generally less than 16 weight%) may improve the acoustic performance of said composition or layer.

[0145] One or more layers of the above multilayer intermediate layer may also include one or more plasticizers. Depending on the specific composition of the layer, the plasticizer is about 5 phr (parts per 100 parts of resin) or more, about 10 phr or more, about 15 phr or more, about 20 phr or more, about 25 phr or more, about 30 phr or more, 35 phr or more, about 40 phr or more, about 45 phr or more, about 50 phr or more, about 55 phr or more, about 60 phr or more and / or about 120 phr or less, about 110 phr or less, about 105 phr or less, about 100 phr or less, about 95 phr or less, about 90 phr or less, about 85 phr or less, about 75 phr or less, about 70 phr or less, about 65 phr or less, about 60 phr or less, about 55 phr or less, about 50 phr or less, about 45 phr or less, or about 40 phr or less, or about 5 It may be present in amounts ranging from phr to about 120 phr, about 10 phr to about 110 phr, about 20 phr to about 90 phr, or about 25 phr to about 75 phr.

[0146] In this document, the terms "parts per 100 parts of resin" or "phr" refer to the amount of plasticizer present per 100 parts of resin by weight. For example, if 30 g of plasticizer is added to 100 g of resin, the plasticizer will be present in an amount of 30 phr. If the layer comprises two or more resins, the parts per 100 parts of resin are determined by comparing the weight of the plasticizer with the total amount of all present resins. Additionally, where the plasticizer content of the layer is provided herein, it is provided in relation to the amount of plasticizer in the mix or melt used to produce the layer.

[0147] Examples of suitable plasticizers include, but are not limited to, triethylene glycol di-(2-ethylhexanoate) ("3GEH"), triethylene glycol di-(2-ethylbutyrate), triethylene glycol diheptanoate, tetraethylene glycol diheptanoate, tetraethylene glycol di-(2-ethylhexanoate) ("4GEH"), dihexyl adipate, dioctyl adipate, hexyl cyclohexyl adipate, diisononyl adipate, heptylnonyl adipate, di(butoxyethyl) adipate, and bis(2-(2-butoxyethoxy)ethyl) adipate, dibutyl sebacate, dioctyl sebacate, and mixtures thereof. The plasticizer may be selected from the group consisting of triethylene glycol di-(2-ethylhexanoate) and tetraethylene glycol di-(2-ethylhexanoate), or the plasticizer may include triethylene glycol di-(2-ethylhexanoate).

[0148] In some embodiments, the plasticizer included in one or more layers may be a high RI plasticizer. As used herein, the term “high RI plasticizer” means a plasticizer having a refractive index of 1.460 or higher when measured by ASTM D542 at a wavelength of 589 nm and a temperature of 25°C. When used, the high RI plasticizer may have a refractive index of about 1.470 or higher, about 1.480 or higher, about 1.490 or higher, about 1.500 or higher, about 1.510 or higher, about 1.520 or higher, and / or about 1.600 or lower, about 1.575 or lower, or about 1.550 or lower when measured as discussed above.

[0149] Examples of types or classes of high RI plasticizers may include, but are not limited to, polyadipates (RI of about 1.460 to about 1.485); epoxides, such as epoxided soybean oil (RI of about 1.460 to about 1.480); phthalates and terephthalates (RI of about 1.480 to about 1.540); benzoates and toluates (RI of about 1.480 to about 1.550); and other specialty plasticizers (RI of about 1.490 to about 1.520). Specific examples of suitable RI plasticizers include, but are not limited to, dipropylene glycol dibenzoate, tripropylene glycol dibenzoate, polypropylene glycol dibenzoate, isodecyl benzoate, 2-ethylhexyl benzoate, diethylene glycol benzoate, butoxyethyl benzoate, butoxyethoxyethyl benzoate, propylene glycol dibenzoate, 2,2,4-trimethyl-1,3-pentanediol dibenzoate, 2,2,4-trimethyl-1,3-pentanediol benzoate isobutyrate, 1,3-butanediol dibenzoate, diethylene glycol di-o-toluate, triethylene glycol di-o-toluate, and dipropylene glycol. It may include di-o-toluate, 1,2-octyl dibenzoate, tri-2-ethylhexyl trimellitate, di-2-ethylhexyl terephthalate, bis-phenol A bis(2-ethylhexaonate), di-(butoxyethyl) terephthalate, di-(butoxyethoxyethyl) terephthalate, and mixtures thereof. High RI plasticizers may be selected from dipropylene glycol dibenzoate and tripropylene glycol dibenzoate, and / or 2,2,4-trimethyl-1,3-pentanediol dibenzoate.

[0150] If the polymer layer or intermediate layer comprises a high RI plasticizer, the plasticizer may be present alone in the layer or may be combined with one or more additional plasticizers. Other plasticizer(s) may also comprise a high RI plasticizer, or one or more of these may be lower RI plasticizers having a refractive index of less than 1.460. In some embodiments, the lower RI plasticizer may have a refractive index of less than about 1.450, less than about 1.445, or less than about 1.442 and may be selected from the group previously listed. If a mixture of two or more plasticizers is used, the mixture may have a refractive index within one or more of the above ranges.

[0151] Poly(vinyl acetal) resins having higher or lower residual hydroxyl and / or residual acetate content may also, when combined with one or more plasticizers, ultimately contain different amounts of plasticizer. Consequently, layers formed from poly(vinyl acetal) resins having different compositions may also have different properties within a single intermediate layer. Without being bound by theory, it is estimated that the compatibility between the proposed plasticizer and the poly(vinyl acetal) resin may depend, at least in part, on the composition of the polymer, and in particular, on its residual hydroxyl content. Overall, poly(vinyl acetal) resins with higher residual hydroxyl content tend to exhibit lower compatibility (or capacity) for the proposed plasticizer compared to similar resins with lower residual hydroxyl content. Consequently, poly(vinyl acetal) resins with higher residual hydroxyl content tend to be less plasticized and exhibit higher stiffness than similar resins with lower residual hydroxyl content. Conversely, poly(vinyl acetal) resins with a lower residual hydroxyl content may tend to incorporate a larger amount of plasticizer when plasticized with the presented plasticizer, which may provide a softer polymer layer exhibiting a lower glass transition temperature than similar resins with a higher residual hydroxyl content. Depending on the specific resin and plasticizer, this tendency may be reversed.

[0152] In some embodiments, the intermediate layer may comprise skin layer(s) comprising poly(vinyl acetal) resin and a plasticizer, and a core or inner polymer layer comprising poly(vinyl acetal) resin and a plasticizer. The plasticizers of the skin layer and the core layer may be of the same type of plasticizer, or the plasticizers may be different. In some embodiments, at least one of the plasticizers may also be a blend of two or more plasticizers. In some embodiments, the core layer may also comprise a plasticizer that may be the same or different from the plasticizer of the skin layer. Additionally, in some embodiments, the two outer skin layers may have nearly identical or identical compositions (including the type and amount of plasticizer).

[0153] Where one of the skin layer and the core layer comprises a poly(vinyl acetal) resin having a residual hydroxyl content that is at least 2 weight percent higher or lower than the residual hydroxyl content of the poly(vinyl acetal) resin of the other layer, the difference in plasticizer content between two or more polymer layers may be at least about 2 phr, about 5 phr, about 8 phr, about 10 phr, about 12 phr, about 15 phr, about 20 phr, about 25 phr, about 30 phr, or about 35 phr. In most embodiments, the polymer layer comprising the resin having a lower hydroxyl content may have a higher plasticizer content. To control or maintain other properties of the polymer layer or intermediate layer, the difference in plasticizer content between the two layers may be about 75 phr or less, about 70 phr or less, about 65 phr or less, about 60 phr or less, about 55 phr or less, about 50 phr or less, about 45 phr or less, about 40 phr or less, about 30 phr or less, about 25 phr or less, about 20 phr or less, or about 17 phr or less. In other embodiments, the difference in plasticizer content between the two polymer layers may be about 40 phr or more, about 50 phr or more, about 60 phr or more, or about 70 phr or more. In some embodiments, the outer skin layer (e.g., the first and second layers) may have a lower plasticizer content than the plasticizer content of the inner core layer (e.g., the third layer).

[0154] Consequently, in some embodiments, at least two of the polymer layers may exhibit different glass transition temperatures. Glass transition temperature or T gG is the temperature marking the transition of a polymer from a glassy state to a rubbery state. The glass transition temperature of the layer described herein was determined by dynamic mechanical thermal analysis (DMTA). DMTA measures the storage (elastic) modulus (G') (in Pa), loss (viscous) modulus (G") (in Pa), and tanδ (G" / G') of the specimen as a function of temperature at the presented vibration frequency and temperature sweep rate. Subsequently, the glass transition temperature is determined by the position of the tanδ peak on the temperature scale. The glass transition temperature provided herein was determined at a vibration frequency of 1 Hz and a temperature sweep rate of 3°C / min under shear mode.

[0155] The difference in glass transition temperatures between two of the above layers (e.g., one of the outer layers and the core layer) is about 2°C or more, about 3°C ​​or more, about 5°C or more, about 8°C or more, about 10°C or more, about 12°C or more, about 15°C or more, about 18°C ​​or more, about 20°C or more, about 22°C or more, about 25°C or more, about 30°C or more, or about 35°C or more and / or about 50°C or less, about 45°C or less, about 40°C or less, about 35°C or less, about 30°C or less, or about 25°C or less. One of the above layers (e.g., skin layer) may have a glass transition temperature in the range of about 26°C or higher, about 28°C or higher, about 30°C or higher, about 33°C or higher, about 35°C or higher and / or about 70°C or lower, about 65°C or lower, about 60°C or lower, about 55°C or lower, about 50°C or lower, about 45°C or lower, about 40°C or lower, about 35°C or lower, about 30°C or lower, or about 25°C or lower, or about 26°C to about 70°C, about 30°C to about 60°C, or about 35°C to about 50°C. The other layer (e.g., core layer) may have a glass transition temperature in the range of 25°C or lower, about 20°C or lower, about 15°C or lower, about 10°C or lower, about 5°C or lower, about 0°C or lower, about -5°C or lower, or about -10°C or lower.

[0156] In some cases, the outer layer(s) of the above multilayer intermediate layer have a higher T g It can have, and thus can be considered a "rigid" outer layer, and the inner layer of the multilayer intermediate layer has a lower T g It may have and can be considered a "flexible" intermediate layer. In some embodiments, the outer skin layer is the T of the inner core layer. g At least about 2°C, at least about 5°C, at least about 10°C, at least about 15°C, at least about 20°C, at least about 25°C, at least about 30°C, or at least about 35°C and / or about 100°C or less, about 90°C or less, about 75°C or less, about 70°C or less, about 65°C or less, about 60°C or less, about 55°C or less, about 50°C or less, about 45°C or less, or about 40°C or less, about 35°C or less, about 30°C or less, or about 25°C or less, with a higher T g Can have.

[0157] In some embodiments, the intermediate layer may comprise one or more polymer films in addition to one or more polymer layers present in the intermediate layer. As used herein, the term “polymer film” refers to a relatively thin and often rigid polymer that imparts some kind of functionality or performance improvement to the intermediate layer. The term “polymer film” differs from the “polymer layer” or “polymer sheet” described herein in that the polymer film itself does not provide the penetration resistance and glass retention properties required for a multilayer panel, but rather provides performance improvements (e.g., infrared-absorbing or reflective properties).

[0158] Poly(ethylene terephthalate) or “PET” may be used to form a polymer film, and ideally, the polymer film used in various embodiments is optically transparent. A polymer film suitable for use in a particular embodiment may also be formed of other materials (e.g., various metals, metal oxides, or other non-metallic materials) and may be coated or otherwise surface-treated. The polymer film may have a thickness of about 0.013 mm or more, about 0.015 mm or more, about 0.020 mm or more, about 0.025 mm or more, about 0.030 mm or more, or about 0.040 mm or more and / or about 0.060 mm or less, about 0.050 mm or less, about 0.045 mm or less, or about 0.035 mm or less. Other types of functional polymer films may include, but are not limited to, an IR reducing layer, a holographic layer, a photochromic layer, an electrochromic layer, an antilacerative layer, a heat strip, an antenna, a solar radiation blocking layer, a decorative layer, and combinations thereof.

[0159] Additionally, one or more layers of the multilayer intermediate layer may comprise one or more types of additives capable of imparting specific properties or characteristics to the polymer layer or intermediate layer. Such additives may include, but are not limited to, dyes, pigments, stabilizers such as UV stabilizers, antioxidants, anti-blocking agents, flame retardants, IR absorbers or blockers such as indium tin oxide, antimony tin oxide, lanthanum hexaboride (LaB6), and cesium tungsten oxide, processing aids, flow enhancers, lubricants, impact modifiers, nucleating agents, heat stabilizers, UV absorbers, dispersants, surfactants, chelating agents, coupling agents, adhesives, primers, reinforcing additives, and fillers. Additionally, to control the adhesion of the layer or intermediate layer to the glass sheet, various adhesion modifiers ("ACA") may also be used in one or more polymer layers. The specific type and amount of such additives may be selected according to the final characteristics or end use of a specific intermediate layer, and may be used to an extent that the additive(s) do not have a negative effect on the final characteristics of the windshield using the intermediate layer configured for the specific use or said intermediate layer.

[0160] In some embodiments, one or more layers of the intermediate layer may comprise an infrared (IR) absorber (or IR absorbing particles). In some cases, only one of the layers (first, second, or third layers) may comprise an IR absorber, and in other embodiments, two or more layers may comprise an IR absorber. When the IR absorber is present in two or more layers, it may be the same or different in each layer, and the amount of the IR absorber in each layer may be the same (i.e., about 0.0050 weight% or less) or different (e.g., greater than or equal to 0.0050 weight%). In some embodiments, the IR absorber may be present in the core layer. In some embodiments, the IR absorber may be present in one or both of the outer skin layers.

[0161] Overall, the IR absorber is about 0.01 wt% or more, about 0.05 wt% or more, about 0.10 wt% or more, about 0.20 wt% or more, about 0.25 wt% or more, about 0.30 wt% or more, about 0.35 wt% or more, about 0.40 wt% or more, about 0.45 wt% or more, about 0.50 wt% or more and / or about 0.75 wt% or less, about 0.70 wt% or less, about 0.65 wt% or less, about 0.60 wt% or less, about 0.55 wt% or less, about 0.50 wt% or less, about 0.45 wt% or less, about 0.40 wt% or less, about 0.35 wt% or less, about 0.30 wt% or less, about 0.25 wt% or less, about 0.20 wt% or less, about 0.15 wt% or less, or about It may be present in the intermediate layer in an amount of 0.10 weight% or less. In this invention, the amount is calculated as an average amount based on the total weight of the sample, layer, or intermediate layer.

[0162] In some embodiments, the amount of IR absorber in one or more layers is, based on the total weight of the layers, about 0.005 wt% or more, about 0.0075 wt% or more, about 0.01 wt% or more, about 0.0125 wt% or more, about 0.015 wt% or more, about 0.0175 wt% or more, about 0.020 wt% or more, about 0.025 wt% or more, about 0.030 wt% or more, about 0.035 wt% or more, about 0.040 wt% or more, about 0.045 wt% or more, about 0.050 wt% or more, about 0.055 wt% or more and / or about 0.090 wt% or less, about 0.080 wt% or more, about 0.075 wt% or less, about 0.070 wt% or less, about 0.065 wt% or less, about 0.060 wt% or less, about It may be 0.055 wt% or less, about 0.050 wt% or less, about 0.045 wt% or less, about 0.040 wt% or less, about 0.035 wt% or less, about 0.030 wt% or less, about 0.025 wt% or less, about 0.020 wt% or less, about 0.015 wt% or less, or about 0.010 wt% or less.

[0163] In some embodiments, the IR absorbent may be substantially absent in one or more layers, for example, such that the amount of the IR absorbent in the layer is less than about 0.010 wt%, less than about 0.005 wt%, less than about 0.001 wt%, or less than about 0.0005 wt% based on the total weight of the intermediate layer. In some embodiments, the IR absorbent may be present in one or both of the outer skin layers in an amount within the above range and may be substantially absent in the inner core layer. In some embodiments, the IR absorbent may be substantially absent in one or both of the outer skin layers and may be present in the inner core layer. In some embodiments, the IR absorbent may be present in all layers of the intermediate layer.

[0164] When present in two or more layers of the above intermediate layer, the amount of IR absorber may be substantially the same in each layer or may differ between the layers. For example, in some embodiments, the absolute value of the difference between the amounts of IR absorber in two of the polymer layers may be about 0.005% or more, about 0.010% or more, about 0.015% or more, about 0.020% or more and / or about 0.035% or less, about 0.030% or less, about 0.025% or less, about 0.020% or less, about 0.015% or less, about 0.010% or less, about 0.005% or less. In some embodiments, the amount of IR absorbent may be substantially the same, such that the absolute value of the difference in the amount of IR absorbent between two or more layers in which the IR absorbent is present is about 0.0010 wt% or less, about 0.005 wt% or less, about 0.003 wt% or less, about 0.002 wt% or less, or about 0.001 wt% or less.

[0165] In some embodiments, the IR absorber may be present in a generally constant amount or concentration from the top to the bottom of the intermediate layer (or from the thinnest edge to the thickest edge of the tapered band). That is, the absolute value of the difference in concentration of the IR absorber between one end of the intermediate layer (or the thinnest edge of the tapered band) and the other end (or the thickest edge of the tapered band) may be less than about 0.0001 weight%, less than about 0.00005 weight%, or less than about 0.00001 weight%. In another embodiment, the absolute value of the difference in concentration of the IR absorber at one end of the intermediate layer (or the thinnest edge of the tapered band) and the other end (or the thickest edge of the tapered band) may be about 0.001 wt% or more, about 0.005 wt% or more, about 0.010 wt% or more, or about 0.025 wt% or more and / or about 0.5 wt% or less, about 0.4 wt% or less, about 0.3 wt% or less, about 0.25 wt% or less, or about 0.10 wt% or less. This may result from the fact that each layer is formed of the same resin (including the concentration of the IR absorber) at the thinnest and thickest parts of the tapered band (or layer or intermediate layer).

[0166] Any suitable type of IR absorbent (or IR absorbent agent) may be used. In some embodiments, the IR absorbent may comprise an organic compound selected from the group consisting of phthalocyanine, naphthalocyanine, anthracyanine, derivatives thereof, and combinations thereof. In some embodiments, the IR absorbent may comprise a metal, such as copper, zinc, vanadium, or a combination thereof. In some embodiments, the IR absorbent may comprise quaternylene imide. Alternatively, one or more IR absorbents as described in U.S. Patent No. 6,737,159 may also be included, either alone or in addition to any IR absorbent described herein, and said Patent is incorporated herein by reference to the extent that it is not inconsistent with the invention.

[0167] The IR absorber may be in any suitable form, for example, in the form of particles. When present in the form of particles, the IR absorber may have a particle size of about 5 nanometers (nm) or more, about 10 nm or more, about 15 nm or more, about 20 nm or more, about 25 nm or more, about 30 nm or more and / or about 100 nm or less, about 90 nm or less, about 80 nm or less, about 70 nm or less, about 60 nm or less, about 50 nm or less, about 40 nm or less, or about 35 nm or less. In some embodiments, the IR absorber may comprise metal oxide particles. Examples of suitable metal oxide particles may include, but are not limited to, metal oxide particles selected from the group consisting of aluminum-doped tin oxide, indium-doped tin oxide, antimony-doped tin oxide (ATO), gallium-doped zinc oxide (GZO), indium-doped zinc oxide (IZO), aluminum-doped zinc oxide (AZO), niobium-doped titanium oxide, sodium-doped tungsten oxide, cesium-doped tungsten oxide, thallium-doped tungsten oxide, rubidium-doped tungsten oxide, tin-doped indium oxide (ITO), tin-doped zinc oxide particles and silicon-doped zinc oxide, lanthanum hexaboride (LaB6), and combinations thereof.

[0168] In some embodiments, the IR absorber particles may comprise tungsten oxide particles represented by one of the following chemical formulas:

[0169] W y O z ,

[0170] [In the above formula, W is tungsten and O is oxygen, satisfying 2.0 < z / y < 3.0, 2.2 ≤ z / y ≤ 2.99, or 2.45 ≤ z / y ≤ 2.99], and / or

[0171] M x W y O z

[0172] [In the above formula, M is H, He, alkali metal, alkaline earth metal, rare earth metal, Mg, Zr, Cr, Mn, Fe, Rh, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re and a combination of two or more of these, W is tungsten, and O is oxygen, wherein 0.001 ≤ x / y ≤ 1.0 or 0.01 ≤ x / y ≤ 0.5, and 2.0 ≤ z / y ≤ 3.0, 2.2 ≤ z / y ≤ 2.99, or 2.45 ≤ z / y ≤ 2.99 are satisfied].

[0173] Examples of tungsten / oxygen ratios are, without limitation, WO 2.92 , WO 2.90 , W 20 O 58 , W 24 O 68 , W 17 O 47 , W 18 O 49 Includes the like. In a preferred embodiment, the tungsten oxide formulation is a cesium tungsten oxide (Cs) having any one of the aforementioned characteristics. 0.33 WO3) and, in various embodiments, Cs 0.33 A cesium tungsten oxide formulation having a WO3 molar ratio is used. In some embodiments, the IR absorbing particles may comprise cesium-doped tungsten oxide, cesium- and tin-doped tungsten oxide, and combinations thereof.

[0174] In some embodiments, one or both of the outer skin layers may include a gradient color band near one or both of the edges of the intermediate layer. The gradient color band may be embedded in all or part of the outer skin layer(s) of the intermediate layer and may have a thickness of about 0.025 mm or more, about 0.05 mm or more, about 0.075 mm or more, about 0.10 mm or more, about 0.125 mm or more, about 0.15 mm or more, about 0.175 mm or more, about 0.20 mm or more, or about 0.225 mm or more and / or about 0.375 mm or less, about 0.35 mm or less, about 0.325 mm or less, about 0.30 mm or less, about 0.275 mm or less, or about 0.25 mm or less. The outer skin layer resin may be present on one or both sides of the intermediate layer with a thickness of about 0.0125 mm or more, about 0.02 mm or more, about 0.025 mm or more, about 0.03 mm or more, or about 0.04 mm or more and / or about 0.075 mm or less, about 0.06 mm or less, about 0.05 mm or less, about 0.04 mm or less, or about 0.035 mm or less. In this document, the term "outer skin layer" includes, if present, a gradient color band.

[0175] According to some embodiments, at least one of the surfaces of the layer or intermediate layer may be textured to facilitate the formation of the intermediate layer or glass plate. For example, at least a portion of at least one of the surfaces of one or more of the layer or intermediate layer may have a surface roughness (R) of about 20 μm or more, about 25 μm or more, about 30 μm or more, 35 μm or more, about 40 μm or more, about 45 μm or more, or about 50 μm or more and / or about 150 μm or less, about 140 μm or less, about 130 μm or less, about 120 μm or less, about 110 μm or less, about 100 μm or less, about 90 μm or less, about 80 μm or less, about 70 μm or less, about 60 μm or less, or about 40 μm or less. z Can have ).

[0176] At this institution, "R z " is a measure of the surface topography of a polymer layer and an indication of the surface's divergence from the plane. Additionally, the surface roughness of the layer is also its R sm It can also be described as a measure of the distance between peaks in the topography of the polymer layer surface. R z and R sm Further description of the method for determining is provided in U.S. Patent No. 7,883,761, the entire patent is incorporated herein by reference to the extent that it is not inconsistent with the present invention.

[0177] R of at least a portion of the surface of one or more layers of the above intermediate layer smIt may be about 300 μm or more, about 325 μm or more, about 350 μm or more, about 375 μm or more, about 400 μm or more, about 425 μm or more, about 450 μm or more, about 475 μm or more, about 500 μm or more, about 525 μm or more, about 550 μm or more, about 575 μm or more, about 600 μm or more, about 625 μm or more, about 650 μm or more, about 675 μm or more, about 700 μm or more, about 725 μm or more, about 750 μm or more, about 775 μm or more, about 800 μm or more, about 825 μm or more, about 850 μm or more, about 875 μm or more, about 900 μm or more, or about 925 μm or more. Alternatively or additionally, Rsm of at least a portion of the surface of one or more layers of the intermediate layer may be about 1000 μm or less, about 950 μm or less, about 900 μm or less, about 850 μm or less, about 800 μm or less, about 750 μm or less, about 700 μm or less, about 650 μm or less, about 600 μm or less, about 550 μm or less, or about 500 μm or less.

[0178] In some embodiments, where two or more surfaces of a single layer or two or more surfaces of different layers are all textured, these surfaces may have different roughness numbers. For example, in some cases, one of the surfaces is R of another surface z R that is at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least 35%, at least about 40%, at least about 45%, or at least about 50% different (i.e., higher or lower) zIt may have a difference of at least about 5 μm, at least about 10 μm, at least about 15 μm, at least about 20 μm, at least about 25 μm, at least about 30 μm, or at least about 35 μm and / or about 100 μm or less, about 75 μm or less, about 60 μm or less, about 50 μm or less, about 40 μm or less, about 35 μm or less, about 30 μm or less, about 25 μm or less, or about 20 μm or less.

[0179] Such roughness can be achieved by any suitable method, e.g., embossing, melt rupture, and combinations thereof, without limitation. A method for determining surface roughness is described in U.S. Patent No. 7,883,761, which is incorporated herein by reference to the extent that it is not inconsistent with the present invention.

[0180] The intermediate layer described herein may be formed by any suitable method. In some embodiments, the method for manufacturing the multilayer intermediate layer may include the step of providing a first type of resin and a second type of resin. The first type of resin may be used, for example, to form a skin layer and may be considered a "skin" resin, and the second type of resin may be used to form a core layer and may be considered a "core" resin. As previously discussed, the skin resin and the core resin may include, for example, poly(vinyl butyral) resin and a plasticizer and may have different compositions.

[0181] To form the intermediate layer described herein, the skin resin may be divided into two or more parts, wherein one part is used to form one of the outer skin layers and the other part is used to form another outer skin layer. In some cases, the first and second parts of the skin resin may be supplied to a die at different material flow rates to form outer skin layers having different thicknesses. In some embodiments, the material flow rate of the resin used to form one of the (thinner) skin layers may be at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, or at least about 80% lower than the material flow rate of the resin used to form the (thicker) skin layer.

[0182] In some embodiments, the material flow rate of the resin used to form one of the skin layers may be about 95% or less, about 90% or less, about 85% or less, about 80% or less, about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, about 50% or less, about 45% or less, about 40% or less, about 35% or less, about 30% or less, or about 25% or less of the material flow rate of the resin used to form another skin layer.

[0183] In some cases, different material flow rates used to form the outer skin layers may be provided by one or more of several techniques. For example, in some embodiments, the skin resin may be divided into two streams, and each stream may be controlled to have a different material flow rate. Consequently, the thickness of each layer may be different, thereby providing an intermediate layer having skin layers as described herein.

[0184] There are various methods for controlling the material flow rate of the skin resin outlet. In some cases, the material flow rate of the skin resin stream can be controlled by using a separate pump to individually control the material flow rate of the resin used to form each outer layer. In some embodiments, different material flow rates of the resins can be achieved by forming the outer skin layers individually using separate extruders, and then joining (together with the core layer) to form a multilayer intermediate layer.

[0185] When forming the intermediate layer, the skin layer resin may be divided into two or more parts used to form at least the outer skin layers. Before forming the layer, the skin resin stream may be divided into two parts using a splitter, and the individual streams may be formed into a sheet or a layer using a die. A first flow path for a first part of the resin melt or stream may be defined between the splitter and the die, and a second flow path may be defined between the splitter and the die, and in some cases, a flow restrictor may be present along the second flow path such that the material flow rate of one of the streams (bypassing or passing through the flow restrictor) is less than the material flow rate of the stream within the first flow path. In some embodiments, the flow restrictor may have a minimum open area of ​​about 95% or less, about 90% or less, about 85% or less, about 80% or less, about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, or about 50% or less of the minimum open area along the first flow path.

[0186] In some embodiments, different material flow rates of resin can be achieved by using melt pipes having different average cross-sectional areas to transport the resin to a die to form each outer skin layer. That is, the diameter of at least a portion of the pipe used to form all or part of the first flow path may be smaller than the diameter of at least a portion of the pipe used to form all or part of the second flow path. In some cases, the minimum diameter of the pipe in the second flow path is at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, or at least about 35% smaller than the minimum diameter of the pipe in the first flow path.

[0187] In some cases, each of the above methods may be used, and in other cases, when forming an intermediate layer as described herein, only one of the above methods or some combination of two or more of them may be used.

[0188] In some embodiments, the formation of the outer skin layer may be performed using a die having a first skin outlet for forming a first outer skin layer and a second skin outlet for forming a second skin layer. The first and second skin outlets may have substantially corresponding thicknesses along the width of the first and second skin outlets. In some cases, these outlets may be geometrically identical and / or, or one or both of the first and second skin outlets may be wedge-shaped.

[0189] In some embodiments, the multilayer intermediate layer may be formed by co-extrusion. In this process, at least three resin streams, including a first outer skin resin stream, a second outer skin resin stream, and an inner core resin stream located between the first outer skin resin stream and the second outer skin resin stream, may be extruded simultaneously from a die to form a co-extruded resin sheet.

[0190] Where at least a portion of the above intermediate layer is formed by co-extrusion, the co-extruded layer may be formed using a multi-manifold die having two or more outlets configured to form layers of different thicknesses and / or shapes. As described herein, to form a skin layer in the final intermediate layer, the flow of the resin (including skin resin) to different outlets may be different.

[0191] In other cases, at least part of the co-extrusion may be formed using a single manifold die, and the flow of skin resin is divided by a die feed block having one or more dividing elements. Subsequently, the generated flow of skin resin can be controlled as described above to provide an intermediate layer having a skin layer as described herein.

[0192] In some embodiments, the multilayer intermediate layer may be formed by individually extruding each of the first outer skin, the second outer skin, and the core layer resin stream to form three individual layers, and then bonding the layers together to form the multilayer intermediate layer.

[0193] In some embodiments, a multilayer intermediate layer can be formed using both co-extrusion and bonding. In some cases, co-extrusion can be used to form a multilayer sheet having, for example, two or more, three or more, or four or more layers. Subsequently, the sheet can be bonded to another sheet having one or more other layers to form a multilayer intermediate layer. In some cases, one or more layers of the sheet may be flat, and one or more layers of the sheet may be wedge-shaped. In some embodiments, the multilayer sheet may have a flat profile and may be bonded to a single-layer sheet having a wedge-shaped profile to provide a wedge-shaped multilayer intermediate layer.

[0194] An intermediate layer constructed and formed according to an embodiment of the present invention may exhibit improved optical and / or acoustic properties compared to an intermediate layer formed from a conventional polymer layer. For example, in some embodiments, the intermediate layer may have a mottle value of about 3.5 or less, about 3.25 or less, about 3 or less, about 2.75 or less, about 2.5 or less, about 2.25 or less, about 2 or less, about 1.75 or less, about 1.5 or less, or about 1 or less. Mottle is a measure of optical quality detected as texture or graininess. If there is too much or too severe mottle, it provides an unpleasant visual appearance to the intermediate layer or glass plate.

[0195] Spots are evaluated and classified by qualitatively comparing a shadowgraph projection of a test laminate side-by-side with a set of standard laminate shadowgraphs representing a series or scale of spot values ​​ranging from 1 to 4, where 1 represents the standard for few spots (i.e., few interruptions) and 4 represents the standard for many spots (i.e., many interruptions). Many spots are generally considered undesirable, particularly in automotive and architectural applications. Optionally, a model laminate with a single interlayer having 0 spots (no spots) is used to facilitate evaluation of test laminates having a spot grade lower than the scale of the standard set (e.g., a grade of less than 1). A test laminate showing a shadowgraph projection similar to a zero-spot laminate is evaluated as having a spot grade of 0. The test laminate is manufactured from two clear glass sheets (commercially available from Pittsburgh Glass Works of Pennsylvania) each having a thickness of 2.3 mm and an intermediate layer. The intermediate layer typically has a random surface roughness (R) of about 35 to 40 μm. zIt has a thickness of 0.76 to 0.86 mm.

[0196] The spot values ​​provided herein were determined using a Clear Mottle Analyzer (CMA) comprising a xenon arc lamp, a sample holder, a projection screen, and a digital camera. The xenon arc lamp is used to project a shadow graph of the bonded sample onto the screen, and the camera is configured to capture an image of the resulting shadow graph. The image is then digitally analyzed using computer imaging software and compared with a previously captured image of a standard sample to determine the spot of the sample. A method for measuring spot using a CMA is described in detail in U.S. Patent No. 9,311,699.

[0197] In some cases, the spot value of an intermediate layer having an outer skin layer of different thickness as described herein is at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, or at least about 95% lower than the spot value of an intermediate layer of the same configuration and composition comprising two outer skin layers of the same thickness.

[0198] Clarity is another optical parameter used to describe the performance of the intermediate layer described herein and can be determined by measuring the haze value or %. The haze value represents the quantification of light scattered by the sample as opposed to incident light. In some embodiments, the resin blend, layer, and intermediate layer described herein may have a haze value of less than 5%, less than about 4%, less than about 3%, less than about 2%, less than about 1%, or less than about 0.5% when measured at an observer angle of 2° using illuminant C in accordance with ASTM D1003-13-Procedure B. The above test is performed on a polymer sample having a thickness of 0.76 mm bonded between two clear glass sheets having a thickness of 2.3 mm each (commercially available from Pittsburgh Glass Works of Pennsylvania) using a spectrophotometer (e.g., Hunterlab UltraScan XE device, commercially available from Hunter Associates, Reston, Virginia, USA).

[0199] In some embodiments, the interlayer described herein may have a visual transmittance % (%Tvis) measured at an observer angle of 2° using illumination C, in accordance with ASTM D1003, Procedure B, using a spectrophotometer (e.g., Hunter Lab UltraScan XE device). The values ​​provided herein are obtained by analyzing a glass laminate sample (marketed by Pittsburgh Glass Works of Pennsylvania) having an interlayer thickness of about 0.76 mm and a clear glass thickness of 2.3 mm. In some embodiments, the polymer layer and the intermediate layer of the present invention may have a visual transmittance of about 65% or more, about 70% or more, about 75% or more, about 80% or more, about 81% or more, about 82% or more, about 83% or more, about 84% or more, about 85% or more, about 85.5% or more, about 86% or more, about 86.5% or more, about 87% or more, about 87.5% or more, about 88% or more, or about 88.5%. The above values ​​may refer to the total or average transmittance of the entire intermediate layer.

[0200] In some embodiments, the intermediate layer may have visual characteristics that are almost unchanged between the thinnest and thickest edges of the tapered band. For example, the intermediate layer may have a visual transmittance (%Tvis) at the thickest edge of the tapered band within about 30%, about 25%, about 20%, about 15%, about 10%, about 5%, about 4.5%, about 4%, about 3.5%, about 3%, about 2.5%, about 2%, about 1.5%, about 1%, about 0.75%, about 0.65%, about 0.60%, about 0.55%, about 0.50%, about 0.45%, and about 0.40% of the visual transmittance (%Tvis) at the thinnest edge of the tapered band. The visual transmittance at the thinnest edge of the tapered band and / or the thickest edge of the tapered band may be at least about 65%, about 70%, about 75%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 85.5%, about 86%, about 86.5%, about 87%, about 87.5%, about 88%, or about 88.5%.

[0201] In some embodiments, the intermediate layer may have a total solar transmittance (%Tts) of about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, about 50% or less, or about 45% or less when measured according to ISO 13837. Additionally, the total solar transmittance may not change substantially across the tapered band despite changes in the thickness profile of one or more layers and the entire intermediate layer. In some embodiments, the intermediate layer is within about 30%, about 25%, about 20%, about 15%, about 10%, about 5%, about 4.5%, about 4%, about 3.5%, about 3%, about 2.5%, about 2%, about 1.5%, about 1%, about 0.75%, about 0.70%, about 0.65%, about 0.60%, about 0.55%, about 0.50%, about 0.45%, about 0.40%, about 0.35%, about 0.30%, about 0.25%, about 0.20%, about 0.15%, about The total solar transmittance (%Tts) (300 nm to 2500 nm) at the thickest edge of the tapered band may be within 0.10%, within about 0.05%, within about 0.01%, within about 0.005%, within about 0.001%, or within about 0%. The total solar transmittance at the thinnest and / or thickest edge of the tapered band may be about 75% or less, about 70% or less, about 65% or less, about 60% or less, about 55% or less, or about 50% or less, about 55% or less, or about 45% or less when measured as described above.

[0202] The intermediate layer described herein may also exhibit desirable acoustic performance. For example, in some embodiments, the intermediate layer according to an embodiment of the present invention may have a tanδ value of about 0.70 or greater. tanδ is the ratio of the loss modulus (G') (in Pa) to the storage modulus (G') (in Pa) of the specimen measured by dynamic mechanical thermal analysis (DMTA). DMTA is performed at a vibration frequency of 1 Hz and a temperature sweep rate of 3°C / min under shear mode. The peak value of the G" / G' curve at the glass transition temperature is the tanδ value. The tanδ of the intermediate layer described herein may be about 1.0 or more, about 1.05 or more, about 1.10 or more, about 1.25 or more, about 1.50 or more, about 1.75 or more, about 2.0 or more, or about 2.25 or more and / or about 5 or less, about 4.75 or less, about 4.5 or less, about 4.25 or less, about 4 or less, about 3.75 or less, about 3.5 or less, about 3.25 or less, about 3 or less, or about 2.5 or less.

[0203] Additionally, the intermediate layer may have a damping loss factor or loss factor of about 0.10 or more, about 0.15 or more, about 0.17 or more, about 0.20 or more, about 0.25 or more, about 0.27 or more, about 0.30 or more, about 0.33 or more, or about 0.35 or more. The loss factor is measured by mechanical impedance measurement as described in ISO standard 16940. A polymer sample is prepared by bonding it between two clear glass plates each having a thickness of 2.3 mm, with a width of 25 mm and a length of 300 mm. Subsequently, the bonded sample is excited at the center point using a commercially available vibrating shaker from Bruel and Kjaer (Nearm, Netherlands), and the force and vibration speed required to excite and vibrate the rod are measured using an impedance head (Bruel and Kjaer). The resulting transfer function is recorded in the National Instruments data acquisition and analysis system, and the loss modulus in the first vibration mode is calculated using the half-power method.

[0204] A plate glass can be formed using the intermediate layer described herein. The plate glass (or laminate or panel) can be formed by interposing an intermediate layer according to an embodiment of the present invention between a first and a second rigid substrate and joining the structure to form a multilayer plate glass. In some embodiments, the plate glass may refer to an intermediate layer (e.g., a double layer) interposed between a rigid substrate and a polymer film.

[0205] A multilayer plate glass or panel as described herein generally comprises a first rigid substrate sheet having a first substrate thickness and a second rigid substrate sheet having a second substrate thickness. Each of the first and second substrates may be formed from a rigid material (e.g., glass) and may be formed from the same or different materials. In some embodiments, at least one of the first and second substrates may be a glass substrate, and in other embodiments, at least one of the first and second substrates may be formed from other materials, such as rigid polymers (e.g., polycarbonate, copolyester, acrylic, polyethylene terephthalate, and combinations thereof). In some embodiments, both of these rigid substrates are glass. Depending on the required performance and properties, any suitable type of non-glass material may be used to form the substrates. Typically, neither of the rigid substrates is formed from a more flexible polymer material (including thermoplastic polymer materials as described in detail below).

[0206] A rigid glass substrate may be formed using any suitable type of glass, and in some embodiments, the glass may be selected from the group consisting of alumina-silicate glass, borosilicate glass, quartz or fused silica glass, and soda-lime glass. When used, the glass substrate may be annealed, thermally strengthened or tempered, chemically tempered, etched, coated, or strengthened by ion exchange, or may be applied to at least one of these treatments. The glass itself may be rolled glass, float glass, or plate glass. In some embodiments, the glass may not be chemically treated or strengthened by ion exchange, and in other embodiments, the glass may not be alumina-silicate glass. Where the first and second substrates are glass substrates, the type of glass used to form each substrate may be the same or different.

[0207] The rigid substrate may have any suitable thickness. In some embodiments, where the rigid substrate is entirely a glass substrate, the nominal thickness of at least one of the glass sheets (the first or second glass) is in the range of 0.1 mm to 12.7 mm, and the multilayer glass panel comprises any combination of the first and second glass sheets (and, if necessary, other glass or rigid sheets). In some embodiments, the nominal thickness of the first and / or second substrate may be about 0.4 mm or more, about 0.5 mm or more, about 0.7 mm or more, about 0.75 mm or more, about 1.0 mm or more, about 1.25 mm or more, about 1.25 mm or more, 1.3 mm or more, about 1.6 mm or more, about 1.9 mm or more, about 2.2 mm or more, about 2.5 mm or more, or about 2.8 mm or more and / or less than about 3.2 mm, less than about 2.9 mm, less than about 2.6 mm, less than about 2.5 mm, less than about 2.3 mm, less than about 2.0 mm, less than about 1.75 mm, less than about 1.7 mm, less than about 1.5 mm, less than about 1.4 mm, or less than about 1.1 mm.

[0208] Additionally or alternatively, the first and / or second substrate may have a nominal thickness of about 2.3 mm or more, about 2.6 mm or more, about 2.9 mm or more, about 3.2 mm or more, about 3.5 mm or more, about 3.8 mm or more, or about 4.1 mm or more and / or about 12.7 mm or less, about 12.0 mm or less, about 11.5 mm or less, about 10.5 mm or less, about 10.0 mm or less, about 9.5 mm or less, about 9.0 mm or less, about 8.5 mm or less, about 8.0 mm or less, about 7.5 mm or less, about 7.0 mm or less, about 6.5 mm or less, about 6.0 mm or less, about 5.5 mm or less, about 5.0 mm or less, or about 4.5 mm or less. Other thicknesses may be appropriate depending on the required application and characteristics.

[0209] If the above-described multilayer panel comprises two substrates having the same nominal thickness, the panel may be referred to as a "symmetric configuration" because the ratio of the nominal thickness of one substrate to the nominal thickness of the other substrate is 1. If the above-described multilayer panel comprises two substrates having different nominal thicknesses, the panel may be referred to as an "asymmetric configuration" because the ratio of the nominal thickness of one substrate to the nominal thickness of the other substrate is not 1. The asymmetric configuration or asymmetric panel used herein is characterized in that the ratio of the thicknesses of the substrates (the ratio of the thinner substrate to the thicker substrate) is less than 1, and the symmetric configuration or symmetric panel is characterized in that the ratio of the thicknesses of the substrates is 1 (i.e., the thicknesses of the substrates are the same).

[0210] In some embodiments, the multilayer panel may comprise two substrates having the same nominal thickness. In other embodiments, the multilayer panel may comprise two substrates having different nominal thicknesses. As used herein, the terms “substrate symmetry” and “glass symmetry” refer to the ratio of the nominal thickness of a first or thinner substrate (or glass sheet) to the nominal thickness of a second or thicker substrate (or glass sheet), and these terms may be used interchangeably. “Glass symmetry” is determined by the following formula VI:

[0211] [Meal VI]

[0212] Rational symmetry (S G ) = H 3 / H 1

[0213] In the above formula, H3 is the nominal thickness of the thinner (first) glass substrate, H1 is the nominal thickness of the thicker (second) glass substrate, and H3 ≤ H1.

[0214] When referring to multilayer glass panels herein, the term "symmetrically configured" refers to the glass symmetry of 1 (S G It means having ), and the term "asymmetrically configured" means having a rational symmetry of less than 1. The terms "rational symmetry," "symmetrically configured," "symmetrical configuration," and "rational configuration symmetry" may be used interchangeably throughout this invention. The terms "asymmetrically configured" and "asymmetrical configuration" may be used interchangeably throughout this invention.

[0215] In some embodiments, the multilayer panel or glass plate as described herein is about 0.10 or more, about 0.15 or more, about 0.20 or more, about 0.23 or more, about 0.25 or more, about 0.30 or more, about 0.35 or more, about 0.40 or more, about 0.45 or more, about 0.50 or more, about 0.55 or more, about 0.60 or more, about 0.65 or more, about 0.70 or more, about 0.75 or more and / or about 1 or less, about 0.99 or less, about 0.97 or less, about 0.95 or less, about 0.90 or less, about 0.85 or less, about 0.80 or less, about 0.75 or less, about 0.70 or less, about 0.65 or less, about 0.60 or less, about 0.55 or less, about 0.50 or less, about 0.45 or less, It may have a glass symmetry of about 0.40 or less, about 0.35 or less, or about 0.30 or less. In some embodiments, the multilayer panel described herein may be symmetric and may have a glass symmetry of 1.

[0216] When the above multilayer panel has an asymmetric configuration, the difference between the nominal thickness of the thicker substrate and the nominal thickness of the thinner substrate may be at least about 0.05 mm. In some embodiments, one or more glass sheets are at least about 0.1 mm, at least about 0.2 mm, at least about 0.3 mm, at least about 0.4 mm, at least about 0.5 mm, at least about 0.6 mm, at least about 0.7 mm, at least about 0.8 mm, at least about 0.9 mm, at least about 1.0 mm, at least about 1.2 mm, at least about 1.6 mm, at least about 2.0 mm, at least about 3.0 mm, or at least about 4.0 mm thicker than the nominal thickness of at least one of the other glass sheets or each of the other glass sheets.

[0217] In some embodiments, one layer of the glass (or hard substrate) is at least about 1.05 times, at least about 1.1 times, at least about 1.2 times, at least about 1.3 times, at least about 1.4 times, at least about 1.5 times, at least about 1.6 times, at least about 1.7 times, at least about 1.8 times, at least about 1.9 times, or at least 2.0 times and / or about 10 times or less, about 8 times or less, about 6 times or less thicker than another layer of the glass (or rigid substrate).

[0218] In some embodiments, one or both of the above materials may be wedge-shaped. Where one or both of the above rigid materials are wedge-shaped materials, the material may limit the wedge angle to about 0.05 mrad or more, about 0.10 mrad or more, about 0.15 mrad or more, about 0.20 mrad or more, about 0.25 mrad or more, about 0.30 mrad or more, or about 0.35 mrad or more and / or about 1 mrad or less, about 0.95 mrad or less, about 0.90 mrad or less, about 0.85 mrad or less, about 0.80 mrad or less, about 0.75 mrad or less, about 0.70 mrad or less, about 0.65 mrad or less, about 0.60 mrad or less, about 0.55 mrad or less. When both of the above descriptions are wedge-shaped, these descriptions may have substantially similar wedge angles within about 0.001 mrad, about 0.005 mrad, or about 0.01 mrad.

[0219] Alternatively, one of the wedge-shaped substrates may have a wedge angle different from the other wedge angle when both of these substrates are wedge-shaped. For example, in some embodiments, one of the substrates may have a wedge angle less than the wedge angle of the other substrate. In some embodiments, the difference between the wedge angles of the two wedge-shaped substrates may be about 0.05 mrad or more, about 0.075 mrad or more, about 0.10 mrad or more, or about 0.12 mrad or more and / or about 0.50 mrad or less, about 0.45 mrad or less, about 0.40 mrad or less, about 0.35 mrad or less, about 0.30 mrad or less, about 0.25 mrad or less, about 0.20 mrad or less, or about 0.15 mrad or less. In some embodiments, one or both of the rigid substrates may each have a uniform thickness (e.g., may not be wedge-shaped or may be substantially flat).

[0220] Examples of suitable types of multilayer panels may include windows for automotive applications, e.g., windshields, side windows, and sunroofs, but not limited to. Examples of suitable types of multilayer panels for architectural applications include, but not limited to, windows; laminated glass panels for doors, walls, ceilings, and passageways, etc.

[0221] In some embodiments, as schematically illustrated in FIG. 7, for example, the windshield (20) formed as described herein may have a thinner lower edge (14) and a thicker upper edge (12). In some cases, the lower edge (14) may have a total thickness of about 1.5 mm or more, about 2 mm or more, about 2.5 mm or more, about 3 mm or more, or about 3.25 mm or more and / or about 10 mm or less, about 8 mm or less, about 6 mm or less, about 5 mm or less, or about 4 mm or less. The thickness of the thicker (upper) edge (12) may be at least about 1.1 times, at least about 1.25 times, at least about 1.5 times, at least about 1.75 times, at least about 2.0 times, at least about 2.25 times, or at least about 2.5 times thicker than the thinner (lower) edge. In some cases, the maximum thickness of the intermediate layer at or near the thinnest (lower) edge (14) of the windshield does not exceed 0.3 mm, 0.29 mm, 0.28 mm, 0.27 mm, 0.26 mm, 0.25 mm, or 0.24 mm within about 40 mm, about 50 mm, about 60 mm, about 70 mm, about 80 mm, or about 85 mm from the thinnest edge (14).

[0222] In some embodiments, the windshield (or other panel) may have a wedge angle of about 0.05 mrad or more, about 0.10 mrad or more, about 0.15 mrad or more, about 0.2 mrad or more, or about 0.3 mrad or more and / or about 1 mrad or less, about 0.90 mrad or less, about 0.80 mrad or less, about 0.75 mrad or less, about 0.70 mrad or less, or about 0.60 mrad or less.

[0223] The following examples further illustrate how the polyester of the present invention may be manufactured and evaluated and how the polyurethane adhesive may be manufactured and evaluated, and are intended to be purely illustrative of the present invention and not intended to limit the scope of the present invention. Unless otherwise indicated, parts are by weight, temperature is in °C (Celsius) or room temperature, and pressure is atmospheric pressure or near it.

[0224] Examples

[0225] Two different multilayer intermediate layers were formed from three layers of poly(vinyl butyral) plasticized with triethylene glycol di-2-ethylhexanoate. The first intermediate layer (comparative intermediate layer 1 (CIL-1)) included two outer skin layers as Skin 1 and Skin 2, as shown in FIG. 10, and an inner core layer as the core layer, as shown in FIG. 10. As shown in FIG. 10, the nominal thickness of Skin 1 and Skin 2 of CIL-1 was nearly the same, and the nominal thickness of the core layer of CIL-1 was thinner than either of the skin layers. A similar second comparative intermediate layer was also formed, referred to herein as comparative intermediate layer 2 (CIL-2). Table 1 below summarizes the composition of the skin and core layers of CIL-1 and CIL-2.

[0226]

[0227] Another intermediate layer (disclosed intermediate layer 1 (DIL-1)) was also formed from three layers of poly(vinyl butyral) having the same composition as the corresponding layer of CIL-1, as summarized in Table 1 above. However, as shown in FIG. 11, one of the outer skin layers of DIL-1 (skin 2) was thinner than the remaining outer skin layers of DIL-1 (skin 1). A similar disclosed second intermediate layer was also formed, referred herein as disclosed intermediate layer 2 (DIL-2).

[0228] The thicknesses of skin layers 1 and 2 and the core layer, respectively, of CIL-1 and 2 and DIL-1 and 2 are summarized in Table 2 below. Additionally, the surface roughness (R) for each skin layer of CIL-1 and 2 and DIL-1 and 2 is z and R sm Measure ) and present in Table 2 below.

[0229]

[0230] As shown above, CIL-1 has a similar surface topography in both of the skin layers and exhibited relatively high spots (3.7). Additionally, CIL-2 has a lower R than CIL-1. z and R sm Despite having [it], CIL-2 still showed a very high spot (3.9).

[0231] Both disclosed intermediate layers 1 and 2 (DIL-1 and DIL-2) included an outer skin layer having a surface topography similar to CIL-2, but exhibited significantly reduced spots (1.2 for DIL-1, and 2.0 for DIL-2).

Claims

Claim 1 A wedge-shaped multi-layer interlayer comprising: a first polymer layer having a wedge shape; a second polymer layer having a wedge shape; and a third polymer layer between the first polymer layer and the second polymer layer, wherein each of the first and second polymer layers has a glass transition temperature (T) of the third polymer layer g T at least 10℃ higher than ) g An intermediate layer having, at one or more locations on the intermediate layer, the second polymer layer is at least 10% thicker than the first polymer layer, and over 100% of the total area of ​​the intermediate layer, the first polymer layer has a thickness of less than 0.30 mm and the second polymer layer has a thickness of more than 0.30 mm. Claim 2 An intermediate layer according to claim 1, wherein the intermediate layer has a thinnest edge and a thickest edge, and the maximum thickness of at least one of the first and second polymer layers does not exceed 0.3 mm within 40 cm from the thinnest edge. Claim 3 delete Claim 4 An intermediate layer according to claim 1, wherein the intermediate layer comprises a tapered band having a thinnest edge and a thickest edge, wherein the ratio of the thickness of the first polymer layer to the total thickness of the intermediate layer at the thinnest edge of the tapered band is at least 0.20:1 and / or 0.85:1 and the ratio of the thickness of the second polymer layer to the total thickness of the intermediate layer at the thinnest edge of the tapered band is at least 0.1:1 and / or 0.45:

1. Claim 5 In claim 1, the intermediate layer is a three-layer intermediate layer, and each of the first, second, and third polymer layers is formed of a plasticized polyvinyl acetal resin, and the third polymer layer has a plasticizer content different from the plasticizer content of the first and / or second polymer layers, ranging from 5 phr (parts per 100 parts of resin) or more and / or 75 phr or less, and the third polymer layer is at the glass transition temperature (T) of the first and / or second polymer layers g ) and T differing from 2℃ or more and / or 50℃ or less g having, wherein the polyvinyl acetal comprises polyvinyl butyral, the polyvinyl butyral in the first and second polymer layers has a residual acetate content of less than 15 weight%, the difference in the residual hydroxyl content of polyvinyl butyral in the first or second polymer layer and the third polymer layer is 3% or more, and at least a portion of the surface of the intermediate layer has a surface roughness (R) of 5 to 75 μm. z An intermediate layer having ), wherein the intermediate layer has an overall wedge angle of 0.05 mrad (milliradian) or more and 1 mrad or less, and the intermediate layer has a mottle value of 3.5 or less. Claim 6 A wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers, wherein the third polymer layer is located between the first polymer layer and the second polymer layer, and each of the first and second polymer layers has a glass transition temperature (T) of the third polymer layer g T at least 10℃ higher than ) g An intermediate layer having, over 100% of the total area of ​​the intermediate layer, the first polymer layer has a thickness of less than 0.30 mm, the second polymer layer has a thickness of greater than 0.30 mm, and the first polymer layer has a thickness profile defined by the following formula: [0.0014( D e ) + 0.06] < T1 < [1.975141 - (1.6936517) / (1 + ( D e / 155.2664)^3.324064)] In the above formula, D e is the distance (cm) from the thinnest edge of the above intermediate layer, and T1 silver D e It is the thickness (mm) of the first polymer layer above. Claim 7 In paragraph 6, D e An intermediate layer having a length of 100 cm or less and a total distance between the thinnest edge and the thickest edge of 50 cm or more. Claim 8 A wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers, wherein the third polymer layer is located between the first polymer layer and the second polymer layer, and at least one of the first and second polymer layers is wedge-shaped; and each of the first and second polymer layers has a glass transition temperature (T) of the third polymer layer g T at least 10℃ higher than ) g An intermediate layer having, over 100% of the total area of ​​the intermediate layer, the first polymer layer has a thickness of less than 0.30 mm and the second polymer layer has a thickness greater than 0.30 mm, the intermediate layer has a tapered band having a thinnest edge and a thickest edge, and the following relationship is satisfied at all points along a vertical centerline extending between the thinnest edge and the thickest edge: 1.25Tca > TcL > 0.75Tca. In the above formula, TcL is the local total thickness of the first and second polymer layers, and Tca is the average total thickness of the first and second polymer layers calculated as follows: Tca = (Tc1 + Tc2) / 2, where Tc1 is the total thickness of the first and second polymer layers at the thinnest edge and Tc2 is the total thickness of the first and second polymer layers at the thickest edge. Claim 9 In claim 8, an intermediate layer wherein at least one of the first, second, and third polymer layers comprises an infrared (IR) absorber. Claim 10 In claim 9, the intermediate layer in which the IR absorbent comprises metal oxide particles. Claim 11 In claim 9, the IR absorbent comprises an intermediate layer having particles with an average particle size of 100 nm or less. Claim 12 A wedge-shaped multilayer intermediate layer comprising first, second, and third polymer layers, wherein the third polymer layer is located between the first polymer layer and the second polymer layer, at least one of the first and second polymer layers is wedge-shaped, and each of the first and second polymer layers has a glass transition temperature (T) of the third polymer layer g T at least 10℃ higher than ) g An intermediate layer having, over 100% of the total area of ​​the intermediate layer, the first polymer layer has a thickness of less than 0.30 mm and the second polymer layer has a thickness of greater than 0.30 mm, the intermediate layer has a tapered band having a total wedge angle of 0.30 mrad or more with the thinnest edge and the thickest edge, and the total solar transmittance (%Tts) measured at the thickest edge of the tapered band is within 3% of the total solar transmittance measured at the thinnest edge of the tapered band, and at least one of the first, second, and third polymer layers comprises an IR absorber, and each of the layers comprising the IR absorber is formed from the same polymer material at both the thinnest edge and the thickest edge of the tapered band. Claim 13 In claim 12, the first polymer layer is wedge-shaped and has a thick end and a thin end, the thick end of the first polymer layer is located at the thinnest edge of the tapered band and the thin end of the first polymer layer is located at the thickest edge of the tapered band, an intermediate layer. Claim 14 A plate glass (glazing) formed from one or more rigid substrates and an intermediate layer of any one of claims 1, 2 and 4 through 13. Claim 15 (a) a step of providing a skin resin; (b) a step of providing a core resin having a composition different from that of the skin resin; (c) a step of forming a first skin layer from a portion of the skin resin and forming a second skin layer from another portion of the skin resin, wherein the forming comprises supplying the resin used to form the first skin layer to a die at a material flow rate lower than the material flow rate of the skin resin used to form the second skin polymer layer; (d) a step of forming a core layer from at least a portion of the core resin; and (e) a step of forming a multilayer polymer layer from the first skin layer, the second skin layer, and the core layer, wherein at one or more locations on the multilayer intermediate layer, the first skin layer is at least 10% thicker than the second skin layer, and each of the first and second skin layers is at the glass transition temperature (T) of the third skin layer g T at least 10℃ higher than ) g A method for manufacturing a multilayer intermediate layer, wherein, over 100% of the total area of ​​the intermediate layer, the first skin layer has a thickness of less than 0.30 mm and the second skin layer has a thickness of more than 0.30 mm. 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