Multi-layer barrier film articles with enhanced adhesion to optical surfaces

The multi-layer construction with a cured (meth)acrylate-based layer and adhesion-promoting agents addresses the delamination issue in quantum dot conversion sheets, enhancing adhesion and preventing moisture ingress, thus maintaining display performance.

WO2025114803A1PCT designated stage expired Publication Date: 2025-06-053M INNOVATIVE PROPERTIES CO
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Patent Information

Application Number
PCT/IB2024/061433
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-11-29
Filing Date
2024-11-15
Publication Date
2025-06-05

AI Technical Summary

Technical Problem

Quantum dot conversion sheets (QCS) in modern display devices face challenges with delamination of barrier layers, leading to moisture and oxygen ingress, which degrades the display's performance over time.

Method used

A multi-layer construction comprising a cured (meth)acrylate-based layer with adhesion-promoting agents, specifically urethane or urea (multi)-(meth)acrylate (multi)-silane, is used to enhance the adhesion between the top polymer barrier layer and the quantum dot layer in optical films.

Benefits of technology

The enhanced adhesion significantly reduces delamination, thereby preventing moisture and oxygen ingress, which maintains the display's brightness and durability over its lifespan.

✦ Generated by Eureka AI based on patent content.

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Abstract

Multi-layer constructions include an optical film with an optical film layer containing quantum dots and a multi-layer barrier film article. The multi-layer article has a first layer, with a first major surface and a second major surface. The second major surface is in contact with a second layer of the multi-layer article and the first major surface is in contact with the optical film layer of the optical film. The first layer includes a cured (meth)acrylate-based layer prepared from at least one (meth)acrylate and at least one adhesion-promoting agent. The adhesion-promoting agent is a urethane or urea (multi)-(meth)acrylate (multi)-silane. The first layer has a higher adhesion to the optical film layer than the same first layer without the adhesion-promoting agent. The multi-layer constructions may contain additional layers and can be included in optical devices.
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Description

[0001] MULTI-LAYER BARRIER FILM ARTICLES WITH ENHANCED ADHESION TO OPTICAL SURFACES

[0002] Summary

[0003] Disclosed here are multi-layer constructions that comprise multi-layer barrier film articles that have enhanced adhesion to optical surfaces, especially optical film layers that contain quantum dots.

[0004] In some embodiments, the multi-layer constructions comprise an optical film comprising an optical film layer containing quantum dots and a multi-layer article. The multi-layer article comprises a first layer, where the first layer has a first major surface and a second major surface. The second major surface of the first layer is in contact with a second layer of the multi-layer article and the first major surface is in contact with the optical film layer of the optical film. The first layer comprises a cured (meth)acrylate- based layer comprising at least one (meth)acrylate and at least one adhesion-promoting agent. The at least one adhesion-promoting agent comprises a urethane or urea (multi)- (meth)acrylate (multi)-silane. The first layer may contain additional components such as additional adhesion promoting agents. The first layer has a higher adhesion to the optical film layer than the same first layer without the adhesion-promoting agent. The multi-layer constructions may contain additional layers and can be included in optical devices.

[0005] Brief Description of the Drawings

[0006] The present application may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings.

[0007] Figure 1 is a cross sectional view of an embodiment of an article of this disclosure.

[0008] Figure 2 is a cross sectional view of another embodiment of an article of this disclosure.

[0009] In the following description of the illustrated embodiments, reference is made to the accompanying drawings, in which is shown by way of illustration, various embodiments in which the disclosure may be practiced. It is to be understood that the embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure. The figures are not necessarily to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0010] Detailed Description

[0011] Modem display devices are becoming increasingly complex. These devices contain a wide range of components to provide a variety of effects. Quantum dots (QD) are used as color conversion materials for LCD (Liquid Crystal Diode) displays. These QDs are susceptible to damage by moisture and oxygen and thus require protection from the environment. This protection is provided by a multi-layer barrier stack that is coated onto optical films to sandwich the QD’s between the optical film and multi-layer barrier stack. This sandwich configuration is a quantum dot conversion sheet (QCS). The optical films on either side of the QD layer have a variety of requirements, including managing the light into and out of the QD layer, sufficient strength to withstand processing conditions, and long-term durability. Examples of withstanding processing conditions include withstanding the forces experienced during converting processes such as die cutting. Forces experienced during converting can be high enough to induce delamination of barrier layers laminated to QD materials. This delamination can cause pathways into the QCS for moisture and oxygen ingress, resulting in a degraded display such as a decrease in brightness, for example. Additional residual forces can be imparted to the QCS part during assembly when the converted QCS sheet is held in place to permit assembly of the device. These residual forces, in combination with the forces experienced during the lifetime of the display and the presence of moisture from the environment can lead to delamination of the barrier layer to the QD materials in the QCS part.

[0012] Disclosed herein are multi-layer constructions comprising an optical fdm with an optical fdm layer and a multi-layer article disposed on the optical fdm layer. The optical fdm layer contains QD materials. This optical fdm layer is an exterior layer of the optical fdm and is referred to herein as an optical fdm layer, a quantum dot layer, or a QD layer. A variety of QD layer materials are suitable such as QDs, QD-matrix resin, and other resins used in the making of the QCS such as those used to make micro-replicated structures and other layers that can affect the light exiting the QDs.

[0013] The multi-layer article is a barrier stack. The barrier stack is typically composed of at least two layers but can contain up to four layers, or more than four layers. The two- layer constructions comprise a top barrier fdm layer and an oxide barrier layer. The four- layer construction comprises a substrate fdm; a base polymer layer; an oxide barrier layer; and an outer most or top barrier polymer layer. The outer most or top barrier layer of the barrier stack is the layer that contacts the QD layer, and therefore, the adhesion of the QD layer / top layer interface is what provides protection to the QD layer and failure of this interface permits ingress of oxygen or water to the QD layer.

[0014] Disclosed herein are materials and methods for increasing the adhesion between the top polymer barrier layer of the barrier stack to the QD layer of the optical fdm. The increased adhesion is obtained by adding adhesion-promoting agents to the top polymer barrier layer of the barrier stack to change the surface chemistry and surface energy. These changes can be measured by, for example, x-ray photoelectron spectroscopy (XPS) and water contact angle.

[0015] The term “(meth)acrylate” refers to monomeric acrylic or methacrylic esters of alcohols. The term “(meth)acrylate-based” refers to materials that contain at least a majority of (meth)acrylates. The term “(meth)acryl” refers to the group -O-C(O)- CR=CH2: where -R is an H or a methyl group, and C(O)- is a carbonyl group C=O.

[0016] The terms “polymer” and “macromolecule” are used herein consistent with their common usage in chemistry. Polymers and macromolecules are composed of many repeated subunits. As used herein, the term “macromolecule” is used to describe a group attached to a monomer that has multiple repeating units. The term “polymer” is used to describe the resultant material formed from a polymerization reaction.

[0017] The term “alkyl” refers to a monovalent group that is a radical of an alkane, which is a saturated hydrocarbon. The alkyl can be linear, branched, cyclic, or combinations thereof and typically has 1 to 20 carbon atoms. In some embodiments, the alkyl group contains 1 to 18, 1 to 12, 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, cyclohexyl, isobomyl, tricyclodecanyl, n-heptyl, n-octyl, and ethylhexyl. The term “aryl” refers to a monovalent group that is aromatic and carbocyclic. The aryl can have one to five rings that are connected to or fused to the aromatic ring. The other ring structures can be aromatic, non-aromatic, or combinations thereof. Examples of aryl groups include, but are not limited to, phenyl, biphenyl, terphenyl, anthryl, naphthyl, acenaphthyl, anthraquinonyl, phenanthryl, anthracenyl, pyrenyl, perylenyl, and fluorenyl.

[0018] The term “alkylene” refers to a divalent group that is a radical of an alkane. The alkylene can be straight-chained, branched, cyclic, or combinations thereof. The alkylene often has 1 to 20 carbon atoms. In some embodiments, the alkylene contains 1 to 18, 1 to 12, 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. The radical centers of the alkylene can be on the same carbon atom (i.e., an alkylidene) or on different carbon atoms.

[0019] The term “arylene” refers to a divalent group that is carbocyclic and aromatic. The group has one to five rings that are connected, fused, or combinations thereof. The other rings can be aromatic, non-aromatic, or combinations thereof. In some embodiments, the arylene group has up to 5 rings, up to 4 rings, up to 3 rings, up to 2 rings, or one aromatic ring. For example, the arylene group can be phenylene.

[0020] Unless otherwise indicated, the terms “optically transparent”, and “visible light transmissive” are used interchangeably, and refer to an article, film or adhesive that has a high light transmittance over at least a portion of the visible light spectrum (about 400 to about 700 nm). Typically, optically transparent articles have a visible light transmittance of at least 90% and a haze of less than 10%.

[0021] Unless otherwise indicated, “optically clear” refers to an adhesive or article that has a high light transmittance over at least a portion of the visible light spectrum (about 400 to about 700 nm), and that exhibits low haze, typically less than about 5%, or even less than about 2%. In some embodiments, optically clear articles exhibit a haze of less than 1% at a thickness of 50 micrometers or even 0.5% at a thickness of 50 micrometers. Typically, optically clear articles have a visible light transmittance of at least 95%, often higher such as 97%, 98% or even 99% or higher.

[0022] Disclosed herein are multi-layer constructions. In some embodiments, the multilayer construction comprises an optical film that comprises an optical film layer that contains quantum dots, and a multi-layer article. The multi-layer article comprises at least 2 layers and typically contains additional layers. The multi-layer article comprises a first layer with a first major surface and a second major surface, where the second major surface is in contact with a second layer of the multi-layer article and the first major surface is in contact with the optical film layer. The first layer comprises a cured (meth)acrylate-based layer comprising at least one (meth)acrylate, and at least one adhesion-promoting agent. The at least one adhesion-promoting agent comprises a urethane or urea (multi)-(meth)acrylate (multi)-silane. The first layer has a higher adhesion to the optical film layer of the optical film than the same first layer without the adhesion-promoting agent.

[0023] The optical film comprises at least one base film layer and the optical film layer that contains quantum dots but may comprise a variety of additional layers. The base film layer may be a monolithic polymeric film, or it may be multi-layer optical film. The base film layer may comprise a single polymeric material, a blend of polymeric materials, polymeric and non-polymeric materials, or as mentioned above it may be a multi-layer film. In some embodiments, the base film layer comprises a thermoplastic polymer film. Suitable thermoplastic polymeric films include those prepared from polyesters, poly(meth)acrylates, polycarbonates, polypropylenes, polyethylenes, copolymers ethylene or propylene, polysulfones, polyether sulfones, polyurethanes, polyamides, polyvinyl butyral, polyvinyl chloride, cyclic olefin polymers, cyclic olefin copolymers, and combinations and copolymers thereof.

[0024] As mentioned above, the optical film comprises an optical film layer that contains quantum dot materials. The quantum dot materials may be just quantum dots or may contain additional components such as resins. The quantum dots in the optical film layer are typically dispersed throughout the optical film layer.

[0025] The multi-layer constructions of this disclosure also comprise a multi-layer article. The multi-layer articles are in contact with the optical film layer and provide barrier properties to the optical film layer. The multi-layer articles comprise at least 2 layers, a first layer and second layer. The multi-layer article may also comprise additional layers.

[0026] The first layer has a first major surface and a second major surface, where the second major surface is in contact with a second layer of the multi-layer article and the first major surface is in contact with the optical film layer. The first layer comprises a cured (meth)acrylate-based layer comprising at least one (meth)acrylate, and at least one adhesion-promoting agent. The at least one adhesion-promoting agent comprises a urethane or urea (multi)-(meth)acrylate (multi) -silane that are described in detail below. The first layer may also comprise additional components.

[0027] A wide variety of (meth)acrylates are suitable to prepare the cured (meth)acrylate- based layer. Examples of useful (meth)acrylates include urethane (meth)acrylates, isobomyl (meth)acrylate, dipentaerythritol penta(meth)acrylates, epoxy (meth)acrylates, epoxy (meth)acrylates blended with styrene, di-trimethylolpropane tetra(meth)acrylates, diethylene glycol di(meth)acrylates, 1,3-butylene glycol di(meth)acrylate, penta(meth)acrylate esters, pentaerythritol tetra(meth)acrylates, pentaerythritol tri(meth)acrylates, ethoxylated (3) trimethylolpropane tri(meth)acrylates, ethoxylated (3) trimethylolpropane tri(meth)acrylates, alkoxylated trifunctional (meth)acrylate esters, dipropylene glycol di(meth)acrylates, neopentyl glycol di(meth)acrylates, ethoxylated (4) bisphenol A di(meth)acrylates, cyclohexane dimethanol di(meth)acrylate esters, cyclic di(meth)acrylates and tris (2-hydroxy ethyl) isocyanurate tri(meth)acrylates, trimethylolpropane tri(meth)acrylate, trimethylolpropane di(meth)acrylate, hexanediol di(meth)acrylate, ethoxyethyl (meth)acrylate, tricyclodecanemethanaol (meth)acrylate, tricyclodecanedimethanol di(meth)acrylate, phenoxyethyl (meth)acrylate, cyanoethyl (mono)(meth)acrylate, octadecyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, beta-carboxyethyl (meth)acrylate, tetrahydrofurfiiryl (meth)acrylate, dinitrile (meth)acrylate, 2-phenoxyethyl (meth)acrylate, and combinations thereof.

[0028] The multi-layer article also comprises a second layer. The second layer is in contact with the first layer. In some embodiments, the second layer of the multi-layer articles comprises an oxide layer. In some embodiments the oxide layer includes at least one oxide, nitride, carbide or boride of atomic elements selected from Groups IIA, IIIA, IVA, VA, VIA, VIIA, IB, or IIB, metals of Groups IIIB, IVB, or VB, rare-earth metals, or a combination or mixture thereof. In some embodiments, the oxide layer includes silicon aluminum oxide. In some particularly suitable embodiments, the oxide layer compositions comprise 75% silicon and 25% aluminum, or 90% silicon and 10% aluminum, or even 95% silicon and 5% aluminum.

[0029] In some embodiments, the multi-layer articles further comprise a third layer. The third layer is in contact with the second layer. The third layer is a (meth)acrylate-based layer that is typically different from the first layer. While the third layer is different from the first layer, the same list of components used to prepare the first layer are likewise suitable for the third layer. Additionally, the third layer may also optionally include an adhesion promoting agent.

[0030] The multi-layer articles may also comprise additional layers. In some embodiments, a fourth layer may be present in the multi-layer articles. If present, the fourth layer is often a base polymeric film. A wide range of base polymeric films are suitable including the base film layers described above. As described above, the base polymeric film may be a monolithic optical polymeric film or a multi-layer optical polymeric film. In some embodiments, the base polymeric film is a flexible transparent polymeric film, comprising polyethylene terephthalate (PET), polyethylene napthalate (PEN), heat stabilized PET, heat stabilized PEN, polyoxymethylene, polyvinylnaphthalene, polyetheretherketone, a fluoro(co)polymer, polycarbonate, polymethylmethacrylate, poly a-methyl styrene, polysulfone, polyphenylene oxide, poly etherimide, polyethersulfone, polyamideimide, polyimide, polyphthalamide, cyclic olefin polymer, cyclic olefin copolymer, or combinations thereof.

[0031] The first layer of the multi-layer article further comprises at least one adhesion promotion agent. The at least one adhesion-promoting agent comprises a urethane or urea (multi)-(meth)acrylate (multi)-silane. The adhesion-promoting agent may comprise more than one urethane or urea (multi)-(meth)acrylate (multi)-silane or may be a urethane or urea (multi)-(meth)acrylate (multi)-silane in combination with a different adhesionpromoting agents as is described below.

[0032] In some embodiments, the urethane or urea (multi)-(meth)acrylate (multi)-silane are of Formula 1 :

[0033] RSI-Z-C(O)-N(H)-RAI

[0034] Formula 1 where:

[0035] -C(O)- is a carbonyl group C=O; Rs i is a silane containing group of the formula: -Rld- Si(Yp)(R2)3-p where Rldis a divalent alkylene, arylene, alkarylene, or aralkylene group, optionally with one or more catenary oxygen atoms; Y is a hydrolysable group, selected from alkoxy, acetate groups, aryloxy groups, and halogens; R2is a monovalent alkyl or aryl group; and p is 1, 2, or 3;

[0036] RAI is a (meth)acryl group containing group of the formula: Rlld-(A) where Rlldis a divalent alkylene, arylene, alkarylene, or aralkylene group, optionally with one or more catenary oxygen atoms; A is a (meth)acryl group comprising the formula -O-C(O)- C(R3)=CH2: R3is H, or methyl; and

[0037] Z is O or N-R4; R4is H, or a Ci to G> alkyl or cycloalkyl.

[0038] In some particular embodiments, the urethane or urea (multi)-(meth)acrylate (multi)-silane are of Formula 1A:

[0039] RSI-Z-C(O)-N(H)-RAI

[0040] Formula 1A where:

[0041] -C(O)- is a carbonyl group C=O; Rs i is a silane containing group of the formula: -Rld- Si(Y)pwhere Rldis a divalent alkylene group; p is 3; Y is a hydrolysable alkoxy group;

[0042] RAI is a (meth)acryl group containing group of the formula: Rlld-(A) where Rlldis a divalent alkylene group; A is a (meth)acryl group comprising the formula -O-C(O)- C(R3)=CH2:

[0043] -C(O)- is a carbonyl group C=O; R3is H; and

[0044] Z is O.

[0045] As mentioned above, the first layer may comprise an additional adhesionpromoting agent, in addition to the above-described adhesion-promoting agent. In some embodiments, the additional adhesion-promoting agent comprises Formula 2:

[0046] H2C=C(R3)-C(O)-O-G-Si(R5)2-Q- Si(R5)2-G-O-C(O)-C(R3)=CH2

[0047] Formula 2 where: each -C(O)- is a carbonyl group C=O; each R3is H, or methyl; each G independently is a divalent alkylene group having from 3-12 carbon atoms; each R5independently is an alkyl group having from 1-6 carbon atoms or a phenyl group;

[0048] Q is a divalent alkylene group having 1-36 carbon atoms.

[0049] In some particular embodiments, the additional adhesion-promoting agent comprises Formula 2A:

[0050] H2C=C(R3)-C(O)-O-G-Si(R5)2-Q- Si(R5)2-G-O-C(O)-C(R3)=CH2

[0051] Formula 2A where: each -C(0)- is a carbonyl group C=O; each R3is methyl; each G is a divalent alkylene group having from 3 carbon atoms; each R5is a methyl group;

[0052] Q is a divalent alkylene group having 2 carbon atoms.

[0053] The amount of adhesion promoting-agent or combination of adhesion-promoting agents present in the first layer can vary. Typically, the at least one adhesion-promoting agent comprises 3-23 % by weight of the total weight of the cured (meth)acrylate-based layer of layer 1.

[0054] In some embodiments, the at least one adhesion-promoting agent comprises at least 3% by weight of a urethane or urea (multi)-(meth)acrylate (multi)-silane are of Formula 1 or Formula 1A shown above.

[0055] In some embodiments, the at least one adhesion-promoting agent comprises at least 3% by weight of a urethane or urea (multi)-(meth)acrylate (multi)-silane are of Formula 1 or Formula 1A shown above, and additionally comprises a second adhesion-promoting agent, wherein the second adhesion-promoting agent is present in an amount of 3-20 weight %. The additional adhesion-promoting agent comprises Formula 2 or Formula 2A shown above.

[0056] The multi-layer constructions of this disclosure may be prepared in a variety of methods. These methods include liquid coating techniques such as solution coating, roll coating, dip coating, spray coating, spin coating; and dry coating techniques such as Chemical Vapor Deposition (CVD), Plasma Enhanced Chemical Vapor Deposition (PECVD), sputtering and vacuum processes for thermal evaporation of solid materials. These coatings and processes can be found, for example, in U.S. Patent Nos. 5,440,446 (Shaw et al.); 5,877,895 (Shaw et al.); 6,010,751 (Shaw et al.); 7,018,713 (Padiyath et al.); and 6,413,645 (Graff et al.). In some embodiments, the first layer is prepared by vapor deposition and curing. In other embodiments, all the layers of the multi-layer article are prepared by vapor deposition.

[0057] Articles of this disclosure may be further understood from the figures. Figure 1 shows article 100 comprising optical film 110 and multi-layer article 120. Optical film 110 comprises base film 111 and optical layer 112 where optical layer 112 contains quantum dots. Multi-layer article 120 comprises first layer 121 and second layer 122. First layer 121 comprises at least one (meth)acrylate and at least one adhesion-promoting agent. Second layer 122 comprises a metal oxide layer.

[0058] Figure 2 shows article 200 comprising optical film 210 and multi-layer article 220. Optical film 210 comprises base film 211 that in this embodiment is shown as a multilayer film, and optical layer 212 where optical layer 212 contains quantum dots. Multilayer article 220 comprises first layer 221, second layer 222, third layer 223, and fourth layer 224. First layer 221 comprises at least one (meth)acrylate and at least one adhesionpromoting agent. Second layer 222 comprises a metal oxide layer. Third layer 223 comprises at least one (meth)acrylate. Fourth layer 224 comprises a base film layer. Each of the layers of the figures is described above.

[0059] Also disclosed are optical devices that comprise the multi-layer constructions described above. Examples of suitable devices include solid state lighting devices, display devices, optical sensors, and combinations thereof. Exemplary solid state lighting devices include semiconductor light-emitting diodes (SLEDs, more commonly known as LEDs), organic light-emitting diodes (OLEDs), or polymer light-emitting diodes (PLEDs). Exemplary display devices include liquid crystal displays, OLED displays, quantum dot displays, and optical sensors.

[0060] Examples

[0061] These examples are merely for illustrative purposes only and are not meant to be limiting on the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight, unless noted otherwise. The following abbreviations are used: m = meters; cm = centimeters; min = minutes; hrs = hours; mJ = milliJoules; mb = milliliters. The terms “weight %”, “% by weight”, and “wt%” are used interchangeably.

[0062] Table of Abbreviations

[0063] Test Methods

[0064] Surface Chemistry Composition by XPS The sample surfaces were examined using X-ray Photoelectron Spectroscopy

[0065] (XPS) also known as Electron Spectroscopy for Chemical Analysis (ESCA). This technique provides an analysis of the outermost 3 to 10 nanometers (nm) on the specimen surface. The photoelectron spectra provide information about the elemental and chemical (oxidation state and / or functional group) concentrations present on a solid surface. It is sensitive to all elements in the periodic table except hydrogen and helium with detection limits for most species in the 0.1 to 1 atomic % concentration range. XPS concentrations should be considered semi-quantitative and for comparable purposes between the examples, comparative examples, and control examples. Water Contact Angle

[0066] The water contact angle of the cured polymer compositions were measured using a Rame-Hart model 290-U 1. The water contact angle can be measured by producing a drop of liquid on a solid surface. The angle formed between the solid / liquid interface and the liquid / vapor interface is referred to as the contact angle. The measurement involves looking at the profile of the drop and measuring two-dimensionally the angle formed between the solid and the drop profile with the vertex at the point where solid, liquid (water) and vapor meet. Young’s equation is then used to describe the forces of cohesion and adhesion and measures the surface energy. The add and remove volume method was used to capture advancing and receding water contact angles reported below. When the receding angle is subtracted from the advancing angle, the result is called the contact angle hysteresis. The hysteresis characterizes surface topology and can help quantify surface chemical heterogeneity and the effect of the additives used in this disclosure.

[0067] FTIR-ATR (Fourier Transform Infrared-Attenuated Reflectance) Spectroscopy

[0068] The extent of reaction and therefore the crosslink density of the cured compositions was analyzed by FTIR-ATR. The single bounce attenuated total reflectance (ATR) accessory is a widely used tool in Fourier Transform Infrared (FTIR) spectroscopy for sampling. It measures the changes that occur in an internally reflected IR beam upon contact with a sample, making it suitable for analyzing liquids, powders, soft polymers such as adhesives and thin-polymer films.

[0069] During analysis, the -log of a single beam sample spectrum is ratioed with a single beam background spectrum, resulting in an absorbance spectrum. The absorbance of specific peaks in the spectrum generally follows the Beer-Lambert law, which states that absorbance is directly proportional to the concentration of the analyte.

[0070] The ATR accessory consists of an optically dense crystal with a high refractive index, typically made of materials like ZnSe, Diamond, Germanium, or Silicon. The choice of crystal depends on the specific application and sample type. Additionally, the depth of penetration in an ATR accessory is influenced not only by the refractive index but also by the angle of incident. In the case of a single bounce accessory, the angle of incident is 45°.

[0071] Among the standard ATR crystals, Germanium provides the lowest depth of penetration. This means that when using a Germanium ATR accessory with a 45° angle of incident, the IR beam will penetrate the sample to a shallower extent compared to other crystals. This characteristic makes the Germanium ATR accessory particularly suitable for analyzing samples with thin layers or surfaces. The instrument used was a Thermo Fisher Nicolet iS20 FTIR spectromenter with an ATR cell accessory. The extent of cure was inferred from the following, the infrared absorption at 1407 cm"1in the thin polymer film of the first layer in the multi-layer film article (barrier stack) was measured. The 1047 cm"1peak is assigned to the carbon-carbon double bond of the (meth)acrylate group and is commonly used to determine extent of cure in a polymerized film material. A separate sample of uncured liquid monomer was then measured for its absorbance and the extent of cure was calculated by ratioing the cured thin polymer film layer to the uncured sample.

[0072] Crosshatch Adhesion Testing:

[0073] Crosshatch adhesion tests on cured samples were performed as described in ASTM D3359-09 (Standard Test Methods for Measuring Adhesion by Tape Test) where OB denotes poor adhesion (greater than 65% of area detached upon tape removal) through a range up to 5B which denotes the best adhesion (no detachment and no damage to scored crosshatch lines upon tape removal). The crosshatch testing was conducted using 3M SCOTCH 232 Tape. Two grids / tests were run for a given formulation. The term ‘zero adhesion’ denotes that it was not possible to conduct a crosshatch test because the coating completely detached from the substrate after cure or during scoring of the crosshatch grid lines.

[0074] Examples

[0075] Comparative Examples CE1, and CE2 - CE4:

[0076] Comparative Example CE1 was prepared with no adhesion promoting agent.

[0077] Comparative Example 1 (CE1) barrier film was made wherein the top polymer formulations composed of Monomer- 1, 1% by weight of PI-1, and no adhesion promoting additives. The polymer formulation was coated and cured in a roll-to-roll vacuum coating process with 5 mJ / cm2of UVC radiation. Surface chemistry composition analyzed by XPS, surface energy measured by water contact angle and the extent of cure and crosslink density measured by FTIR-ATR.

[0078] Comparative Examples CE2-CE4 were prepared with a comparative adhesion promoting agent.

[0079] A series of comparative barrier films were made wherein the top polymer formulations composed Monomer- 1, 1% by weight of PI-1, and varying concentration of Additive- 1. Comparative Example CE2 had 3% by weight of Additive- 1, Comparative Example CE3 had 10% by weight of Additive- 1, and Comparative Example CE4 had 20% by weight of Additive- 1. The polymer formulations were coated and cured in a roll-to-roll vacuum coating process with 5 mJ / cm2of UVC radiation. Surface chemistry composition analyzed by XPS, surface energy measured by water contact angle and the extent of cure and crosslink density measured by FTIR-ATR.

[0080] Example 1

[0081] A series of barrier fdms were made wherein the top polymer formulations composed of Monomer- 1, 1% by weight of PI-1, and varying concentration of Additive 2. Example 1A had 3% by weight Additive-2, Example IB had 10% by weight Additive-2, and Example 1C had 20% by weight Additive-2. The polymer formulations were coated and cured in a roll-to-roll vacuum coating process with 5 mJ / cm2of UVC radiation. Surface chemistry composition analyzed by XPS, surface energy measured by water contact angle and the extent of cure and crosslink density measured by FTIR-ATR. The data are shown in Table 1.

[0082] Table 1: Example 1 Data

[0083] Example 2:

[0084] A series of barrier fdms were made wherein the top polymer formulations composed of Monomer- 1. Example 2A was a barrier fdm wherein the top polymer formulation was composed of Monomer- 1, 1% by weight of PI-1, and a mixture of additives comprising 3% by weight Additive-2 and 3% by weight of Additive-3. A second barrier fdm (Example 2B) was composed of Monomer- 1, 1% by weight of PI-1, and a mixture of additives comprising 3% by weight Additive-2 and 20% by weight of Additive-3. Both top polymer layer formulations were coated and cured in a roll-to-roll vacuum coating process with 5 mJ / cm2 of UVC radiation. Surface chemistry composition analyzed by XPS, surface energy measured by water contact angle and the extent of cure and crosslink density measured by FTIR-ATR. The data for Example 2 and CE2 - CE4 are shown in Table 2.

[0085] Table 2: Example 2 and CE2-CE4 Data

[0086] Coating Preparations for Crosshatch Testing:

[0087] The Crosshatch Adhesion of the coatings of this disclosure to an aromatic urethane acrylate layer was tested, the data are presented in Table 3. Coating formulations like those described above were prepared and a layer of aromatic urethane acrylate was prepared on top of the coatings. These formulations are labeled CEE, CE2’-CE5’, 1A’, 1B1, 1C’, 2A’ and 2B’. The formulations were prepared as described above, and on these coatings an aromatic urethane acrylate layer was formed. The aromatic urethane acrylate layer was prepared from Monomer-2. The aromatic urethane acrylate layer compositions were Monomer-2, 2 wt% of PI-2, and MEK at 58.5 wt% total solids. Thick (-100 micrometer thick) coatings were prepared by pipetting solution (0.5 mb) onto substrates and thin (-25 micrometer thick) coatings were prepared by casting with a wire-wound no. 10 Meyer rod (RDS Specialties, Webster, NY). MEK was removed (70°C, 30 mins) from the substrates, and ultraviolet (UV) curing of the coatings was performed using a “LIGHT HAMMER” system (Heraeus Noblelight Fusion UV Inc., Gaithersburg, MD) using a “D- bulb” with three passes of the conveyor belt running at 30 feet per minute (9.3 m / min). Table 3. Crosshatch adhesion results for a range of substrates.

[0088] The crosshatch adhesion data shows that Additive- 1 is ineffective at increasing the adhesion of the coatings to the aromatic urethane acrylate substrate. Additive-2 is effective at increasing adhesion but this effect is reduced at higher levels of additive, and the combination of Additive-2 and Additive-3 is likewise very effective at high levels of Additive-3.

Claims

What is claimed is:

1. A multi-layer construction comprising: an optical film comprising an optical film layer containing quantum dots; and a multi-layer article, wherein the multi-layer article comprises: a first layer, wherein the first layer has a first major surface and a second major surface, wherein the second major surface is in contact with a second layer of the multi-layer article and the first major surface is in contact with the optical film layer of the optical film, wherein the first layer comprises: a cured (meth)acrylate-based layer comprising: at least one (meth)acrylate; and at least one adhesion-promoting agent, wherein the at least one adhesion-promoting agent comprises a urethane or urea (multi)- (meth)acrylate (multi)-silane; and wherein the first layer has a higher adhesion to the optical film layer than the same first layer without the adhesion-promoting agent.

2. The multi-layer construction of claim 1, wherein the optical film layer comprises a urethane-(meth)acrylate .

3. The multi-layer construction of claim 1, wherein the second layer of the multi-layer articles comprises an oxide layer with a first major surface and a second major surface, wherein the first major surface of the oxide layer is in contact with the second major surface of the first layer, and the second major surface of the oxide layer is in contact with a third layer, wherein the third layer is a (meth)acrylate-based layer that is different from the first layer.

4. The multi-layer construction of claim 1, wherein the urethane or urea (multi)- (meth)acrylate (multi) -silane are of Formula 1:RSI-Z-C(O)-N(H)-RAIFormula 1 wherein:-C(O)- is a carbonyl group C=O;Rsi is a silane containing group of the formula: -Rld-Si(Yp)(R2)3-p wherein:Rldis a divalent alkylene, arylene, alkarylene, or aralkylene group, optionally with one or more catenary oxygen atoms;Y is a hydrolysable group, selected from alkoxy, acetate groups, aryloxy groups, and halogens;R2is a monovalent alkyl or aryl group; and p is 1, 2, or 3;RAI is a (meth)acryl group containing group of the formula: Rlld-(A) wherein:Rlldis a divalent alkylene, arylene, alkarylene, or aralkylene group, optionally with one or more catenary oxygen atoms;A is a (meth)acryl group comprising the formula -O-C(O)-C(R3)=CH2: wherein -C(O)- is a carbonyl group C=O;R3is H, or methyl; andZ is O or N-R4; andR4is H, or a Ci to Ce alkyl or cycloalkyl.

5. The multi-layer construction of claim 1, wherein the urethane or urea (multi)- (meth)acrylate (multi) -silane are of Formula 1A:RSI-Z-C(O)-N(H)-RAIFormula 1A wherein:-C(O)- is a carbonyl group C=O; andRsi is a silane containing group of the formula: -Rld-Si(Y)pwherein:Rldis a divalent alkylene group; p is 3;Y is a hydrolysable alkoxy group; andRAI is a (meth)acryl group containing group of the formula: Rlld-(A) wherein:Rlldis a divalent alkylene group;A is a (meth)acryl group comprising the formula -O-C(O)-C(R3)=CH2: wherein -C(O)- is a carbonyl group C=O;R3is H; andZ is O.

6. The multi-layer construction of claim 1, wherein the first layer comprises an additional adhesion-promoting agent.

7. The multi-layer construction of claim 6, wherein the additional adhesion-promoting agent comprises Formula 2:H2C=C(R3)-C(O)-O-G-Si(R5)2-Q- Si(R5)2-G-O-C(O)-C(R3)=CH2Formula 2 wherein: each -C(O)- is a carbonyl group C=O; each R3is H, or methyl; each G independently is a divalent alkylene group having from 3-12 carbon atoms; each R5independently is an alkyl group having from 1-6 carbon atoms or a phenyl group;Q is a divalent alkylene group having 1-36 carbon atoms8. The multi-layer construction of claim 6, wherein the additional adhesion-promoting agent comprises Formula 2A:H2C=C(R3)-C(O)-O-G-Si(R5)2-Q- Si(R5)2-G-O-C(O)-C(R3)=CH2Formula 2A wherein: each -C(O)- is a carbonyl group C=O; each R3is methyl; each G is a divalent alkylene group having from 3 carbon atoms; each R5is a methyl group;Q is a divalent alkylene group having 2 carbon atoms.

9. The multi-layer construction of claim 1, wherein the at least one adhesion-promoting agent comprises 3-23 % by weight of the total weight of the cured (meth)acrylate-based layer.

10. The multi-layer construction of claim 9, wherein the at least one adhesion-promoting agent comprises at least 3% by weight of a urethane or urea (multi)-(meth)acrylate (multisilane are of Formula 1:RSI-Z-C(O)-N(H)-RAIFormula 1 wherein:-C(O)- is a carbonyl group C=O;Rsi is a silane containing group of the formula: -Rld-Si(Yp)(R2)3-p wherein:Rldis a divalent alkylene, arylene, alkarylene, or aralkylene group, optionally with one or more catenary oxygen atoms;Y is a hydrolysable group, selected from alkoxy, acetate groups, aryloxy groups, and halogens;R2is a monovalent alkyl or aryl group; and p is 1, 2, or 3;RAI is a (meth)acryl group containing group of the formula: Rlld-(A) wherein:Rlldis a divalent alkylene, arylene, alkarylene, or aralkylene group, optionally with one or more catenary oxygen atoms;A is a (meth)acryl group comprising the formula -O-C(O)-C(R3)=CH2: wherein -C(O)- is a carbonyl group C=O;R3is H, or methyl; andZ is O or N-R4; andR4is H, or a Ci to Cg alkyl or cycloalkyl.

11. The multi-layer construction of claim 10, wherein the urethane or urea (multi)- (meth)acrylate (multi) -silane are of Formula 1A:RSI-Z-C(O)-N(H)-RAIFormula 1A wherein:-C(O)- is a carbonyl group C=O; andRsi is a silane containing group of the formula: -Rld-Si(Y)pwherein:Rldis a divalent alkylene group; p is 3;Y is a hydrolysable alkoxy group; andRAI is a (meth)acryl group containing group of the formula: Rlld-(A) wherein:Rlldis a divalent alkylene group;A is a (meth)acryl group comprising the formula -O-C(O)-C(R3)=CH2: wherein -C(O)- is a carbonyl group C=O;R3is H; andZ is O.

12. The multi-layer construction of claim 10, further comprising a second adhesionpromoting agent, wherein the second adhesion-promoting agent is present in an amount of 3-20 weight %.

13. The multi-layer construction of claim 12, wherein the additional adhesion-promoting agent comprises Formula 2:H2C=C(R3)-C(O)-O-G-Si(R5)2-Q- Si(R5)2-G-O-C(O)-C(R3)=CH2Formula 2 wherein: each -C(O)- is a carbonyl group C=O; each R3is H, or methyl; each G independently is a divalent alkylene group having from 3-12 carbon atoms; each R5independently is an alkyl group having from 1-6 carbon atoms or a phenyl group;Q is a divalent alkylene group having 1-36 carbon atoms14. The multi-layer construction of claim 12, wherein the additional adhesion-promoting agent comprises Formula 2A:H2C=C(R3)-C(O)-O-G-Si(R5)2-Q- Si(R5)2-G-O-C(O)-C(R3)=CH2Formula 2A wherein: each -C(O)- is a carbonyl group C=O; each R3is methyl; each G is a divalent alkylene group having from 3 carbon atoms; each R5is a methyl group;Q is a divalent alkylene group having 2 carbon atoms15. The multi-layer construction of claim 1, wherein the first layer is prepared by vapor deposition and curing.

16. The multi-layer construction of claim 1, wherein all the layers of the multi-layer article are prepared by vapor deposition.

17. An optical device comprising the multi-layer construction of claim 1.

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